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Publications dans les journaux scientifiques dans le domaine de l'ingénierie : 05-2017 trié par par titre, page: 6
» Managing New Technology Using Malleable Profit Functions
Résumé:
Technological innovation drives economic growth, and the pioneering activity of scientists and engineers produce technological innovation. We provide a mathematical model of pioneering strategic choice by adopting a perspective familiar to microeconomics, but less common in the engineering management literature. Instead of focusing on the specific features of a pioneer's technology, we focus on the malleability of the profit equation involved. By considering the arguments of the profit function (i.e., entry and variable costs and potential market demand) as strategic levers, we derive propositions that identify the ranges of actions (lever pulling) available to managers to protect (and even increase) entrepreneurial rents in a simple yet robust partial equilibrium case. For each lever, we show that there are several value ranges (intervals) and that the pioneer's incentives vary across these intervals. In addition, for each lever, we identify the existence of nontrivial profit discontinuities that change the pioneer's incentives in surprising ways and lead to counterintuitive strategic choices. Lastly, we show that for some range of each lever's values, welfare-improving transfer payments are possible and, therefore, pioneers and policy-makers both have an incentive to bargain. As in the case of patents, these transfers encourage the introduction of new technologies.
Auteurs: Richard Arend;Moren Levesque;Maria Minniti;
Apparue dans: IEEE Transactions on Engineering Management
Date publication: 05.-2017, volume: 64, issue:2, pages: 120 - 133
Editeur: IEEE
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» Mapping Thermokarst Lakes on the Qinghai–Tibet Plateau Using Nonlocal Active Contours in Chinese GaoFen-2 Multispectral Imagery
Résumé:
In order to monitor the response of thermokarst lakes on the Qinghai–Tibet Plateau (QTP) to rapid climatic changes and human activities, an automated method for extracting shorelines from Chinese GaoFen-2 (GF-2) imagery is proposed. First, the water index (WI) images and the potential lake areas are calculated from the preprocessed multispectral imagery and digital elevation model data, respectively. Second, the initial segmentation obtained by global thresholding of the WI images and masking in the potential lake areas are used to implement the contour initialization of active contours models efficiently. Finally, the nonlocal active contours (NLAC) approach is applied to refine the initial segmentation of the WI images, and the final shoreline vector files are produced by some simple and automatic postprocessing steps. Experiments on the GF-2 imagery demonstrate that 1) by exploiting the capability of WI to locate the approximate shoreline effectively around the evolving contour, the processing time of the proposed method can be saved significantly; 2) the NLAC approach can efficiently identify the shoreline by integrating the nonlocal interactions between pairs of patches inside and outside the lake; and 3) the proposed method can conveniently adapt to the multitemporal and multifeature image analysis. Using the manual digitized shorelines as the reference data, an average error of less than one pixel with standard deviation of 0.1320 can be obtained. These results prove that the proposed method is feasible for the identification and monitoring of thermokarst lakes on the QTP.
Auteurs: Bangsen Tian;Zhen Li;Meimei Zhang;Lei Huang;Yubao Qiu;Zhixian Li;Panpan Tang;
Apparue dans: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Date publication: 05.-2017, volume: 10, issue:5, pages: 1687 - 1700
Editeur: IEEE
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» Matchable-Observable Linear Models and Direct Filter Tuning: An Approach to Multivariable Identification
Résumé:
Identification of linear time-invariant multivariable systems can best be understood as comprising three separate problems: selection of system model structure, filter design, and parameter estimation itself. Approaching the first using matchable-observable models originally developed in the adaptive control literature and the second via direct or derivative-free optimization, effective least-squares algorithms can be used for parameter estimation. The accuracy, robustness and moderate computational demands of the methods proposed are demonstrated via simulations with randomly generated models and applied to identification using real process data. The results obtained are comparable or superior to the best results obtained using standard implementations of the algorithms described in the literature.
Auteurs: Rodrigo Alvite Romano;Felipe Pait;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 05.-2017, volume: 62, issue:5, pages: 2180 - 2193
Editeur: IEEE
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» Matching Network Elimination in Broadband Rectennas for High-Efficiency Wireless Power Transfer and Energy Harvesting
Résumé:
Impedance matching networks for nonlinear devices such as amplifiers and rectifiers are normally very challenging to design, particularly for broadband and multiband devices. A novel design concept for a broadband high-efficiency rectenna without using matching networks is presented in this paper for the first time. An off-center-fed dipole antenna with relatively high input impedance over a wide frequency band is proposed. The antenna impedance can be tuned to the desired value and directly provides a complex conjugate match to the impedance of a rectifier. The received RF power by the antenna can be delivered to the rectifier efficiently without using impedance matching networks; thus, the proposed rectenna is of a simple structure, low cost, and compact size. In addition, the rectenna can work well under different operating conditions and using different types of rectifying diodes. A rectenna has been designed and made based on this concept. The measured results show that the rectenna is of high power conversion efficiency (more than 60%) in two wide bands, which are 0.9–1.1 and 1.8–2.5 GHz, for mobile, Wi-Fi, and ISM bands. Moreover, by using different diodes, the rectenna can maintain its wide bandwidth and high efficiency over a wide range of input power levels (from 0 to 23 dBm) and load values (from 200 to 2000 Ω). It is, therefore, suitable for high-efficiency wireless power transfer or energy harvesting applications. The proposed rectenna is general and simple in structure without the need for a matching network hence is of great significance for many applications.
Auteurs: Chaoyun Song;Yi Huang;Jiafeng Zhou;Paul Carter;Sheng Yuan;Qian Xu;Zhouxiang Fei;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3950 - 3961
Editeur: IEEE
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» MAVEN: An Algorithm for Multi-Parametric Automated Segmentation of Brain Veins From Gradient Echo Acquisitions
Résumé:
Cerebral vein analysis provides a chance to study, from an unusual viewpoint, an entire class of brain diseases, including neurodegenerative disorders and traumatic brain injuries. Manual segmentation approaches can be used to assess vascular anatomy, but they are observer-dependent and time-consuming; therefore, automated approaches are desirable, as they also improve reproducibility. In this paper, a new, fully automated algorithm, based on structural, morphological, and relaxometric information, is proposed to segment the entire cerebral venous system from MR images. The algorithm for multi-parametric automated segmentation of brain VEiNs (MAVEN) is based on a combined investigation of multi-parametric information that allows for rejection of false positives and detection of thin vessels. The method is tested on gradient echo brain data sets acquired at 1.5, 3, and 7 T. It is compared to previous methods against manual segmentation, and its inter-scan reproducibility is assessed. The achieved accuracy and reproducibility are good, meaning that MAVEN outperforms previous methods on both quantitative and qualitative analyses. It is usable at all the field strengths explored, showing comparable accuracy scores, with no need for algorithm parameter adjustments, and thus, it is a promising candidate for the characterization of the venous tree topology.
Auteurs: Serena Monti;Sirio Cocozza;Pasquale Borrelli;Sina Straub;Mark E. Ladd;Marco Salvatore;Enrico Tedeschi;Giuseppe Palma;
Apparue dans: IEEE Transactions on Medical Imaging
Date publication: 05.-2017, volume: 36, issue:5, pages: 1054 - 1065
Editeur: IEEE
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» Maximum Achievable Power Conversion Efficiency Obtained Through an Optimized Rectenna Structure for RF Energy Harvesting
Résumé:
High-efficiency rectennas for radio frequency (RF) energy harvesting have been studied for decades, but most of the literature straightforwardly applies the rectenna aiming at dedicated RF sources to this situation, even though the level of input power is significantly different. Since previous studies address antenna design collecting more ambient RF power, the improvement of power conversion efficiency (PCE) has emerged in a scattered way, because the theoretical limit of PCE has not yet been characterized, and the optimal rectenna structure approaching such maximum PCE is still uninvestigated. In this paper, we characterize the performance limit of rectennas with input power ranging from −20 to 0 dBm, proposing optimal rectenna design demonstrating the maximum PCE. The maximum achievable PCE is cast into a mathematical programming problem. Solving this optimization model clarifies the effect of design factors, including operational frequencies, rectifier topologies, and parameterization. To achieve the maximum PCE, our investigation shows that the optimal rectenna structure should not only optimize those design factors but also eliminate the matching circuit between an antenna and a rectifier for ultralow-power scenarios. The resultant PCE at 2.45 GHz is 61.4% and 31.8% at −5 and −15 dBm, respectively, closely approaching the theoretical bound.
Auteurs: Yen-Sheng Chen;Cheng-Wei Chiu;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2305 - 2317
Editeur: IEEE
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» Mean-Field Dynamics of Inter-Switching Memes Competing Over Multiplex Social Networks
Résumé:
This letter characterizes the intertwined behavior of a susceptible-infected-susceptible epidemic model involving multiple mutually exclusive memes, each competing over distinct contact planes of an undirected multi-layer social network, with the possibility of inter-switching. Based on the mean-field theory, we contrast and derive closed-form analytical expressions for the steady-state thresholds that govern the transitions between extinction, co-existence, and absolute dominance of the inter-switchable memes. Moreover, a non-linear optimization formulation is presented to determine the optimal budget allocation for controlling the switching rates to a particular co-existing meme. Validated by simulations, the impact of switching on the tipping thresholds and their implications in reality are demonstrated using data extracted from online social networks.
Auteurs: Aresh Dadlani;Muthukrishnan Senthil Kumar;Manikanta Gowtham Maddi;Kiseon Kim;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 967 - 970
Editeur: IEEE
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» Measurement of the Mass Flow and Velocity Distributions of Pulverized Fuel in Primary Air Pipes Using Electrostatic Sensing Techniques
Résumé:
Online measurement of pulverized fuel (PF) distribution between primary air pipes on a coal-fired power plant is of great importance to achieve balanced fuel supply to the boiler for increased combustion efficiency and reduced pollutant emissions. An instrumentation system using multiple electrostatic sensing heads is developed and installed on 510-mm bore primary air pipes on the same mill of a 600-MW coal-fired boiler unit for the measurement of PF mass flow and velocity distributions. An array of electrostatic electrodes with different axial widths is housed in a sensing head. An electrode with a greater axial width and three narrower electrodes are used to derive the electrostatic signals for the determination of PF mass flow rate and velocity, respectively. The PF velocity is determined by multiple cross correlation of the electrostatic signals from the narrow electrodes. The measured PF velocity is applied on the root-mean-square magnitude of the measured electrostatic signal from the wide electrode for the calibration of PF mass flow rate. On-plant comparison trials of the developed system were conducted under five typical operating conditions after a system calibration test. Isokinetic sampling equipment is used to obtain reference data to evaluate the performance of the developed system. Experimental data demonstrate that the developed system is effective and reliable for the online continuous measurement of the mass flow and velocity distributions between the primary air pipes of the same mill.
Auteurs: Xiangchen Qian;Yong Yan;Xiaobin Huang;Yonghui Hu;
Apparue dans: IEEE Transactions on Instrumentation and Measurement
Date publication: 05.-2017, volume: 66, issue:5, pages: 944 - 952
Editeur: IEEE
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» Measurement-Directed Reduction of Dynamic Models in Power Systems
Résumé:
The paper describes a new model reduction procedure tailored to power systems. It uses measurement data to devise a family of reduced order nonlinear models while retaining physical interpretability of parameters and equations. The manifold boundary approximation method (MBAM) uses the Fisher information matrix calculated from measurements to identify the least relevant parameter combination in the original model. Next, it numerically constructs a geodesic on the corresponding statistical manifold originating from the initial parameters in the least relevant parameter direction until a manifold boundary is found. MBAM then identifies a limiting approximation in the mathematical form of the model and removes one parameter combination. The simplified model is recalibrated by fitting its behavior to that of the original model, and the process is repeated as appropriate. MBAM is demonstrated on the example of a synchronous generator (SG), which has been treated extensively in the literature. Implications of the proposed model reduction procedure on large power system models are illustrated on a 441-bus, 72-SG dynamical model.
Auteurs: Mark K. Transtrum;Andrija T. Sarić;Aleksandar M. Stanković;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 2243 - 2253
Editeur: IEEE
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» Measuring and Understanding RRC State Machine Optimization in Light of Recent Advancements
Résumé:
Broadband mobile networks utilize a radio resource control (RRC) state machine to allocate scarce radio resources. Current implementations introduce high latencies and cross-layer degradation. Recently, the RRC enhancements, continuous packet connectivity (CPC), and the enhanced forward access channel (Enhanced FACH), have emerged in UMTS. We measure the availability and performance of these enhancements on a network serving a market with a population in the millions. We demonstrate that these enhancements offer significant reductions in latency, mobile device energy consumption, and improved end user experience. We develop new over-the-air measurements that resolve existing limitations in measuring RRC parameters. We find CPC provides significant benefits with minimal resource costs, prompting us to rethink past optimization strategies. We examine the cross-layer performance of CPC and Enhanced FACH, concluding that CPC provides reductions in mobile device energy consumption for many applications. While the performance increase of HS-FACH is substantial, cross-layer performance is limited by the legacy uplink random access channel (RACH), and we conclude full support of Enhanced FACH is necessary to benefit most applications. Given that UMTS growth will exceed LTE for several more years and the greater worldwide deployment of UMTS, our quantitative results should be of great interest to network operators adding capacity to these networks. Finally, these results provide new insights for application developers wishing to optimize performance with these RRC enhancements.
Auteurs: Xuetao Wei;Theodore Stoner;Joseph Knight;Lei Guo;
Apparue dans: IEEE Transactions on Mobile Computing
Date publication: 05.-2017, volume: 16, issue:5, pages: 1330 - 1342
Editeur: IEEE
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» Measuring Azimuth Deformation With L-Band ALOS-2 ScanSAR Interferometry
Résumé:
We analyze the methods for measuring azimuth deformation with the L-band Advanced Land Observing Satellite-2 (ALOS-2) scanning synthetic aperture radar (ScanSAR) interferometry. To implement the methods, we extract focused bursts from the ALOS-2 full-aperture product, which is the only product available for ScanSAR interferometry at present. The extracted bursts are properly processed to measure azimuth deformation using interferometric phase. We apply the range split-spectrum method to ScanSAR to estimate the differential ionospheric phase of the interferogram, and take the azimuth derivative of the differential ionospheric phase to mitigate the relative azimuth shift caused by ionosphere. For the first time, azimuth deformation of a large earthquake (April 25, 2015 Nepal earthquake) is nearly completely measured by the L-band ScanSAR interferometry with moderate precision. The result is validated by the azimuth deformation measured by incoherent cross correlation using a pair of high-resolution RADARSAT-2 images. In addition to the final azimuth deformation, we show the possibility of processing full-aperture ScanSAR product using a burst-by-burst approach to form regular interferograms. We also show the recent strong large-scale ionospheric effects on the L-band ALOS-2 ScanSAR interferograms. Other possible applications of this paper include measuring the movement of glaciers.
Auteurs: Cunren Liang;Eric J. Fielding;
Apparue dans: IEEE Transactions on Geoscience and Remote Sensing
Date publication: 05.-2017, volume: 55, issue:5, pages: 2725 - 2738
Editeur: IEEE
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» Mechanomyography Assisted Myoeletric Sensing for Upper-Extremity Prostheses: A Hybrid Approach
Résumé:
The myoelectric upper-limb prosthetic manipulation is inherently limited by the unreliable sensor-skin interface. This paper presents a hybrid approach to overcome the limitation of electromyography (EMG) through mechanomyography (MMG) assisted myoelectric sensing. An integrated hybrid sensor system was developed for simultaneous EMG and MMG measurement. The hybrid system formed a platform to capture muscular activations in different frequencies. To evaluate the effectiveness of hybrid EMG-MMG sensing, hand motion experiments have been carried out on seven able-bodied and two transradial amputee subjects. It convincingly demonstrated, a significantly ( ${p} <0.01$ ) improved classification accuracy (CA). Furthermore, the CA was compensated by 8.7% ~ 33.7% in the presence of 2 ~ 3 fault EMG channels. These results suggest that MMG assisted myoelectric sensing can improve the control performance and robustness. It has great potential to promote the clinical application of multi-functional prosthetic hand with hybrid EMG-MMG sensor system.
Auteurs: Weichao Guo;Xinjun Sheng;Honghai Liu;Xiangyang Zhu;
Apparue dans: IEEE Sensors Journal
Date publication: 05.-2017, volume: 17, issue:10, pages: 3100 - 3108
Editeur: IEEE
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» Meetings Calendar
Résumé:
The following list of meetings, conferences, and symposia is provided as a reader service and does not constitute endorsement by the IEEE or the IEEE Dielectrics and Electrical Insulation Society. This calendar can also be found at http://sites.ieee.org/deis.
Auteurs: Davide Fabiani;
Apparue dans: IEEE Electrical Insulation Magazine
Date publication: 05.-2017, volume: 33, issue:3, pages: 46 - 47
Editeur: IEEE
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» Method of Generating Femtosecond Cylindrical Vector Beams Using Broadband Mode Converter
Résumé:
We experimentally obtain femtosecond cylindrical vector beams based on a mode-locked fiber laser (MLFL) by using a fused few-mode coupler. Pulses of 300 fs duration with radially and azimuthally polarized modes are directly delivered at the central wavelength of 1566 nm. The fused few-mode fiber coupler inserted inside the cavity acts as a mode converter from LP01 mode to LP11 mode with a wide bandwidth over 100 nm. The proof-of-concept generation of femtosecond cylindrical vector beams is efficient and useful in MLFLs.
Auteurs: Feng Wang;Fan Shi;Teng Wang;Fufei Pang;Tingyun Wang;Xianglong Zeng;
Apparue dans: IEEE Photonics Technology Letters
Date publication: 05.-2017, volume: 29, issue:9, pages: 747 - 750
Editeur: IEEE
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» Mg Doping to Simultaneously Improve the Electrical Performance and Stability of MgInO Thin-Film Transistors
Résumé:
In this paper, we have fabricated the magnesium-doped indium oxide (MgInO) thin-film transistors (TFTs) by solution process and evaluate the electrical characteristics and stability under temperature stress and positive bias stress. The MgInO TFTs show a decrease of off-state current ( ${text {I}}_{{mathrm{scriptscriptstyle off}}})$ and an increase of threshold voltage ( ${text {V}}_{mathrm {TH}})$ with the increase of Mg doping concentration. For MgInO TFT with 0.75 mol% Mg doping concentration, it shows an excellent electrical characteristic (the field effectmobility of 13.77 cm $^{2} {text {V}}^{-1}~text{s}^{-1}$ , the threshold voltage of 2.84 V, and subthreshold swing value of 0.85 V/decade) and a good stability of temperature stress and positive bias stress. The performance enhancement of MgInO TFTs is attributed to the reduced density of states and the lower interface trap density by the optimized Mg doping concentration, which is first verified by the temperature-dependent field effect measurement and capacitance–voltage method.
Auteurs: Cheng-Yu Zhao;Jun Li;De-Yao Zhong;Chuan-Xin Huang;Jian-Hua Zhang;Xi-Feng Li;Xue-Yin Jiang;Zhi-Lin Zhang;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 05.-2017, volume: 64, issue:5, pages: 2216 - 2220
Editeur: IEEE
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» Microscopic Origin of Electron Transport Properties and Ultrascalability of Amorphous Phase Change Material Germanium Telluride
Résumé:
The electron transport in prototypical amorphous ( ${a}$ -) phase change material (PCM) germanium telluride is investigated using density functional theory, ab initio molecular dynamics, nonequilibriumGreen’s function, and quantum hydrodynamics. It is found that the measured peculiar electron transport properties of ${a}$ -PCM are governed by bias-dependent dynamics of local current swirls, which originate from defects-induced electron backscattering and localization. The microscopic balance between defects-induced electron localization and field-induced electron delocalization is the origin of the linear, exponential, and S-shape snapback current–voltage curve shapes. It is revealed that the threshold switching is a manifestation of quantum percolation. It is shown that the local current swirls are well confined in Å-scale, leading to the promising single-digit nanometer scalability of related device technologies.
Auteurs: Jie Liu;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 05.-2017, volume: 64, issue:5, pages: 2207 - 2215
Editeur: IEEE
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» Microwave Characteristics of an Independently Biased 3-Stack InGaP/GaAs HBT Configuration
Résumé:
This paper investigates various important microwave characteristics of an independently biased 3-stack InGaP/GaAs heterojunction bipolar transistor (HBT) monolithic microwave integrated circuit (MMIC) chip at both small-signal and large-signal operation. By taking the advantage of the independently biased functionality, bias condition for individual transistor can be adjusted flexibly, resulting in the ability of independent control for both small-signal and large-signal performances. It was found that at small-signal operation stability and isolation characteristics of the proposed configuration can be significantly improved by controlling bias condition of the second-stage and the third-stage transistors while at large-signal operation its linearity and power gain can be improved through controlling the bias condition of the first-stage and the third-stage transistors. To demonstrate the benefits of using such an independently biased configuration, a measured optimum large-signal performance at an operation frequency of 1.6 GHz under an optimum bias condition for the high gain, low distortion were obtained as: $text {PAE} = 23.5,,%$ , ${text {P}}_{text {out}}= 12$ dBm; ${text {Gain}}= 32.6$ dB at IMD3 = −35 dBc. Moreover, to demonstrate the superior advantage of the proposed configuration, its small-signal and large-signal performance were also compared to that of a single stage common-emitter, a conventional 2-stack, an independently biased 2-stack and a conventional 3-stack configuration. The compared results showed that the independently biased 3-stack is the best candidate among the configurations for various wireless communications applications.
Auteurs: Manh Duy Luong;Ryo Ishikawa;Yoichiro Takayama;Kazuhiko Honjo;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 05.-2017, volume: 64, issue:5, pages: 1140 - 1151
Editeur: IEEE
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» Microwave Voltage-Controlled Oscillator With Harmonic-Suppressed Stepped-Impedance-Resonator Filter
Résumé:
This brief proposes a new low-phase-noise microwave voltage-controlled oscillator (VCO) with a harmonic-suppressed stepped-impedance-resonator (SIR) filter. Since the filter is synthesized by multiple resonators, it can provide a high-quality factor to improve the phase-noise performance. In addition, the harmonic-suppressed property of the filter adopted in this brief can alleviate the noise contributed from the oscillation harmonics. By applying the two techniques mentioned, the proposed VCO is designed at 2.4 GHz with a three-pole Butterworth filter, which is synthesized by the parallel transmission-line SIRs to reduce the circuit size. The proposed VCO using a three-pole filter has a measured phase noise of −147 dBc/Hz at 1-MHz offset frequency with a corresponding figure-of-merit of −203.18 dBc/Hz.
Auteurs: Chao-Hsiung Tseng;Tien-Sheng Huang;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 05.-2017, volume: 64, issue:5, pages: 520 - 524
Editeur: IEEE
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» Microwaves-Based High Sensitivity Sensors for Crack Detection in Metallic Materials
Résumé:
This paper presents a highly sensitive sensor for crack detection in metallic surfaces. The sensor is inspired by complementary split-ring resonators which have dimensions much smaller than the excitation’s wavelength. The entire sensor is etched in the ground plane of a microstrip line and fabricated using printed circuit board technology. Compared to available microwave techniques, the sensor introduced here has key advantages including high sensitivity, increased dynamic range, spatial resolution, design simplicity, selectivity, and scalability. Experimental measurements showed that a surface crack having 200- $mu text{m}$ width and 2-mm depth gives a shift in the resonance frequency of 1.5 GHz. This resonance frequency shift exceeds what can be achieved using other sensors operating in the low GHz frequency regime by a significant margin. In addition, using numerical simulation, we showed that the new sensor is able to resolve a 10- $mu text{m}$ -wide crack (equivalent to $lambda $ /4000) with 180-MHz shift in the resonance frequency.
Auteurs: Ali M. Albishi;Omar M. Ramahi;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 05.-2017, volume: 65, issue:5, pages: 1864 - 1872
Editeur: IEEE
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» Mid-Infrared Waveguide Array Inter-Chip Coupling Using Optical Quilt Packaging
Résumé:
A MEMS-based mid-infrared (MIR) chip-to-chip optical coupling technique, optical quilt packaging (OQP), is described. Numerical simulations are performed to predict performance and establish fabrication tolerances. The OQP fabrication process is described in detail and MIR inter-chip optical coupling between two waveguide arrays joined by OQP is characterized. The coupling loss between Ge-on-Si passive MIR waveguides is found to be ~ 4.1 dB, which is the lowest butt-coupling loss reported between two chips.
Auteurs: Tahsin Ahmed;Tian Lu;Thomas P. Butler;Jason M. Kulick;Gary H. Bernstein;Anthony J. Hoffman;Douglas C. Hall;Scott S. Howard;
Apparue dans: IEEE Photonics Technology Letters
Date publication: 05.-2017, volume: 29, issue:9, pages: 755 - 758
Editeur: IEEE
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» Migration From Fixed to Flexible Grid Optical Networks With Sub-Band Virtual Concatenation
Résumé:
A novel strategy is presented to operate a mixed fixed/flexible grid optical network which may be used to gradually migrate from a fixed to a flexible mode of operation. Routing and spectrum allocation (RSA) in an optical network where fixed and flexible grids co-exist using a multi-path sub-band virtual concatenation (VCAT) or split spectrum (SS) technique is considered. Mixed integer linear programming models and an efficient heuristic algorithm based on spectrum window planes are proposed for the RSA optimization. The results obtained for the static traffic demand indicate that it is operationally more convenient to use the multi-path VCAT only by itself in a mixed grid optical network to guarantee performance comparable to that of the joint multi-path and single-path VCAT case. Network performance is also evaluated in terms of bandwidth blocking probability (BBP) under a dynamic traffic demand. Simulation results show that the multi-path VCAT scheme can efficiently utilize the overall spectrum resources with low blocking. The results of studies with both static and dynamic traffic demands also confirm that migration from a pure fixed grid optical network to a pure flexible grid will be desirable for better network capacity utilization.
Auteurs: Ya Zhang;Yao Zhang;Sanjay K. Bose;Gangxiang Shen;
Apparue dans: Journal of Lightwave Technology
Date publication: 05.-2017, volume: 35, issue:10, pages: 1752 - 1765
Editeur: IEEE
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» MIMO Energy Harvesting in Full-Duplex Multi-User Networks
Résumé:
This paper considers the efficient design of precoding matrices for sum throughput maximization under throughput quality of service (QoS) constraints and energy harvesting (EH) constraints for energy-constrained devices in a full-duplex (FD) multicell multi-user multiple-input-multiple-output network. Both time splitting (TS) and power splitting are considered to ensure practical EH and information decoding. These problems are quite complex due to non-concave objectives and nonconvex constraints. Especially, with TS, which is implementation-wise quite simple, the problem is even more challenging because the time splitting variable is not only coupled with the downlink throughput function but also coupled with the self-interference in the uplink throughput function. New path-following algorithms are developed for their solutions, which require only a single convex quadratic program for each iteration and ensure rapid convergence. Moreover, the FD EH maximization problem under throughput QoS constraints with TS is also considered. The performance of the proposed algorithms is compared with that of the modified problems assuming half-duplex systems. Finally, the merit of the proposed algorithms is demonstrated through extensive simulations.
Auteurs: Ho Huu Minh Tam;Hoang Duong Tuan;Ali Arshad Nasir;Trung Q. Duong;H. Vincent Poor;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 05.-2017, volume: 16, issue:5, pages: 3282 - 3297
Editeur: IEEE
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» MIMO Sphere Decoding With Successive Interference Cancellation for Two-Dimensional Non-Uniform Constellations
Résumé:
Non-uniform constellations (NUCs) have been introduced to improve the performance of quadrature amplitude modulation constellations. 1D-NUCs keep the squared shape, while 2D-NUCs break that constraint to provide robustness. An impending problem with multiple-input multiple-output (MIMO) is the optimum demapping complexity, which grows exponentially with the number of antennas and the constellation order. Some well-known sub-optimum MIMO demappers, such as soft fixed-complexity sphere decoders (SFSD), can reduce that complexity. However, SFSD demappers do not work with the 2D-NUCs, since they perform a quantization step in separated I/Q components. In this letter, we provide an efficient solution for the 2D-NUCs based on Voronoi regions. Both complexity implications and SNR performance are also analyzed.
Auteurs: Carlos Barjau;Manuel Fuentes;Takuya Shitomi;David Gómez-Barquero;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1015 - 1018
Editeur: IEEE
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» Miniature Low-Cost Carbon Dioxide Sensor for Mobile Devices
Résumé:
We present our recent advances on developing a miniature sensor for carbon dioxide that may be used in mobile devices. Until now, limiting factors for the implementation of gas sensors in mobile devices, such as smartphones, include their production costs and large size, which is associated with the comparatively poor sensitivity. To overcome these constraints, we employ a photoacoustic-based infrared detection technology to gauge the light intensity of a mid-infrared LED. The photoacoustic detector mainly consists of a commercially available microphone inside a hermetically sealed, carbon dioxide filled cell. To save space and minimize intensity losses, a novel waveguide is used to direct the LED radiation to the detector. The waveguide simultaneously forms the measuring chamber. Because of the high sensitivity of our device, the overall size can be reduced to a level where it is compatible with standard IC sockets. Gas measurements were performed that demonstrate the suitability of the sensor. While providing high sensitivity, the influence of humidity on the sensor signal is insignificant and influences due to temperature shifts may be compensated for.
Auteurs: Louisa Scholz;Alvaro Ortiz Perez;Benedikt Bierer;Ponkanok Eaksen;Jürgen Wöllenstein;Stefan Palzer;
Apparue dans: IEEE Sensors Journal
Date publication: 05.-2017, volume: 17, issue:9, pages: 2889 - 2895
Editeur: IEEE
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» Miniaturization of Frequency Selective Surfaces Using 2.5-D Knitted Structures: Design and Synthesis
Résumé:
This paper explores the potential of using vias for the miniaturization of frequency selective surfaces (FSSs). A new concept of knitting the loop-type FSS elements in 2.5-D is proposed, where successive segments of the loop are placed alternately on the two surfaces of the substrate and then interconnected through vias. A 2.5-D square-loop FSS (2.5-D SL-FSS) based on the proposed method is designed with the inclusion of ten vias at each side and characterized by a full-wave simulator. The transmission curves indicate a significant size reduction with a figure-of-merit $lambda _{0}/p = 16$ , where $lambda _{0}$ is the free-space wavelength of resonant frequency and $p$ is the periodicity of unit element. In addition, the frequency response of this miniaturized FSS is also stable for various incident angles and polarizations. Furthermore, a general equivalent circuit model (ECM) is developed for 2.5-D SL-FSS by combining the prevailing electrical models of planar square loop and through-silicon vias. A wide set of parametric simulations for various element sizes, substrate thicknesses, and via counts are carried out with this ECM. Then, its performance is assessed on the basis of root-mean-square error (RMSE) criteria by comparing the results with appropriate electromagnetic simulations. The findings suggest that the ECM has sufficient accuracy for estimating the resonant frequency of 2.5-D SL-FSS with the RMSE values close to 3%. Moreover, the proposed concept of knitting is further validated by measuring two physical prototypes of the 2.5-D SL-FSS and the experimental results show a good consistency with full-wave simulations.
Auteurs: Tauseef Hussain;Qunsheng Cao;Jahangir Khan Kayani;Irfan Majid;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2405 - 2412
Editeur: IEEE
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» Miniaturized Millimeter-Wave Radar Sensor for High-Accuracy Applications
Résumé:
A highly miniaturized and commercially available millimeter wave (mmw) radar sensor working in the frequency range between 121 and 127 GHz is presented in this paper. It can be used for distance measurements with an accuracy in the single-digit micrometer range. The sensor is based on the frequency modulated continuous wave (CW) radar principle; however, CW measurements are also possible due to its versatile design. An overview of the existing mmw radar sensors is given and the integrated radar sensor is shown in detail. The radio frequency part of the radar, which is implemented in SiGe technology, is described followed by the packaging concept. The radar circuitry on chip as well as the external antennas is completely integrated into an 8 mm $times ,, 8$ mm quad flat no leads package that is mounted on a low-cost baseband board. The packaging concept and the complete baseband hardware are explained in detail. A two-step approach is used for the radar signal evaluation: a coarse determination of the target position by the evaluation of the beat frequency combined with an additional determination of the phase of the signal. This leads to an accuracy within a single-digit micrometer range. The measurement results prove that an accuracy of better than $pm 6~mu text{m}$ can be achieved with the sensor over a measurement distance of 35 mm.
Auteurs: Mario Pauli;Benjamin Göttel;Steffen Scherr;Akanksha Bhutani;Serdal Ayhan;Wolfgang Winkler;Thomas Zwick;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 05.-2017, volume: 65, issue:5, pages: 1707 - 1715
Editeur: IEEE
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» Miniaturized Transparent Metallodielectric Resonator Antennas Integrated With Amorphous Silicon Solar Cells
Résumé:
Miniaturized transparent metallodielectric resonator antennas are developed and integrated on amorphous silicon solar cells. The horizontal metallic strips attached on the sidewalls of transparent low-profile dielectric resonators are used to manipulate electric near-fields and achieve novel dominant modes that represent miniaturized narrowband, wideband, or multiband antennas with various far-field properties. The radiation properties of each mode can also be adjusted to suit a prospective application by a simple change in position and/or size of the strip. The horizontal strip on the sidewall can be as narrow as one twelfth of the resonator height, and the top wall of the resonator is always kept clear to maximize the solar cell efficiency. A comprehensive comparison including far-field, near-field, and impedance properties of different modes is presented. Several prototypes of the integrated antennas were fabricated and tested. The experimental results are along with the theoretical achievements showing miniaturized antennas with maximum dimension as small as $0.18lambda $ and multimode operation with realized gain higher than 6 dBi.
Auteurs: Atabak Rashidian;Lotfollah Shafai;Cyrus Shafai;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2265 - 2275
Editeur: IEEE
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» Minimal Load Shedding Using the Swing Equation
Résumé:
Load shedding constitutes the very last resort for preventing total blackouts and cascading events. Conventional load shedding schemes, which are massively applied in industrial practice, adopt a step-wise approach that usually causes overshedding or fails to prevent frequency decay above the allowable limits. Recently proposed schemes based on real time intelligent control and neural networks achieve the control objective, but fail to minimize the amount of load to be shed due to the delay incurred in consecutive control decisions. This letter proposes a new load shedding scheme, decoupled from the conventional scheme. This scheme, based on the equivalent swing equation of the system, determines the minimal amount of load that should be shed immediately (in a single step) after the load event/disturbance occurs, in order to guarantee system stability.
Auteurs: Yiannis Tofis;Stelios Timotheou;Elias Kyriakides;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 2466 - 2467
Editeur: IEEE
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» Minimax Compression and Large Alphabet Approximation Through Poissonization and Tilting
Résumé:
This paper introduces a convenient strategy for coding and predicting sequences of independent, identically distributed random variables generated from a large alphabet of size $m$ . In particular, the size of the sample is allowed to be variable. The employment of a Poisson model and tilting method simplifies the implementation and analysis through independence. The resulting strategy is optimal within the class of distributions satisfying a moment condition, and it is close to optimal for the class of all i.i.d distributions on strings of a given length. The method also can be used to code and predict strings with a condition on the tail of the ordered counts, and it can be applied to distributions in an envelope class. Moreover, we show that our model permits exact computation of the minimax optimal code, for all alphabet sizes, when conditioning on the size of the sample.
Auteurs: Xiao Yang;Andrew R. Barron;
Apparue dans: IEEE Transactions on Information Theory
Date publication: 05.-2017, volume: 63, issue:5, pages: 2866 - 2884
Editeur: IEEE
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» Minimization of Waiting Time Variation in a Generalized Two-Machine Flowshop With Waiting Time Constraints and Skipping Jobs
Résumé:
Wafer quality issues are becoming essential concerns in semiconductor manufacturing industry. It is becoming increasingly important for fab managers to raise the wafer quality level. Quality variation across wafers and wafer lots is also recognized as of vital importance. Wafer waiting times, which occur between consecutive wafer processing steps, are critical for the quality and quality variation of wafers. To resolve these quality issues, we consider waiting time constraints and variation in a flowshop. To follow the actual operating features of the fab, we define a two-machine flowshop with jobs that can skip the first process step and are ready to enter the second step from the beginning of scheduling. This research thus examines a machine scheduling problem that minimizes the variation in job waiting times in a generalized two-machine flowshop with skipping jobs and waiting time constraints. The mathematical properties of the problem such as the dominance properties and feasibility conditions are vigorously analyzed. These analyses provide profound insights into reduction of the search space in the solution procedure. We also observe that the derived properties are intuitively consistent with the well-known principles of queueing theory. From these, we develop efficient approximation algorithms and present their computational performance.
Auteurs: Tae-Sun Yu;Hyun-Jung Kim;Tae-Eog Lee;
Apparue dans: IEEE Transactions on Semiconductor Manufacturing
Date publication: 05.-2017, volume: 30, issue:2, pages: 155 - 165
Editeur: IEEE
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» Minimizing Coefficients Wordlength for Piecewise-Polynomial Hardware Function Evaluation With Exact or Faithful Rounding
Résumé:
Piecewise polynomial interpolation is a well-established technique for hardware function evaluation. The paper describes a novel technique to minimize polynomial coefficients wordlength with the aim of obtaining either exact or faithful rounding at a reduced hardware cost. The standard approaches employed in literature subdivide the design of piecewise-polynomial interpolators into three steps (coefficients calculation, coefficients quantization and arithmetic hardware optimization) and estimate conservatively the overall approximation error as the sum of the error components arising in each step. The proposed technique, using Integer Linear Programming (ILP), optimizes the polynomial coefficients taking into account all error components simultaneously. This gives two advantages. Firstly, we can obtain exactly rounded approximations; secondly, for faithfully rounded interpolators, we avoid any overdesign due to pessimistic assumptions on error components, optimizing in this way the resulting hardware. The proposed ILP based algorithm requires an acceptable CPU time (from few seconds to tens of minutes) and is suited for approximations up to, maximum, 24 input bits. The results compare favorably with previously published data. We present synthesis results in 28 nm and 90 nm CMOS technologies, to further assess the effectiveness of the proposed approach.
Auteurs: Davide De Caro;Ettore Napoli;Darjn Esposito;Gerardo Castellano;Nicola Petra;Antonio G. M. Strollo;
Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers
Date publication: 05.-2017, volume: 64, issue:5, pages: 1187 - 1200
Editeur: IEEE
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» Mixed Iterative Adaptive Dynamic Programming for Optimal Battery Energy Control in Smart Residential Microgrids
Résumé:
In this paper, a novel mixed iterative adaptive dynamic programming (ADP) algorithm is developed to solve the optimal battery energy management and control problem in smart residential microgrid systems. Based on the data of the load and electricity rate, two iterations are constructed, which are $P$ -iteration and $V$ -iteration, respectively. The $V$-iteration is implemented based on value iteration, which aims to obtain the iterative control law sequence in each period. The $P$-iteration is implemented based on policy iteration, which updates the iterative value function according to the iterative control law sequence. Properties of the developed mixed iterative ADP algorithm are analyzed. It is shown that the iterative value function is monotonically nonincreasing and converges to the solution of the Bellman equation. In each iteration, it is proven that the performance index function is finite under the iterative control law sequence. Finally, numerical results and comparisons are given to illustrate the performance of the developed algorithm.
Auteurs: Qinglai Wei;Derong Liu;Frank L. Lewis;Yu Liu;Jie Zhang;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 4110 - 4120
Editeur: IEEE
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» Mobility Aware Virtual Network Embedding
Résumé:
Over the last years, network virtualization has become one of the most promising solutions for sustainability towards the ongoing increase of data demand in mobile networks. Within that context, the virtual network embedding problem has recently been studied extensively and many different solutions have been proposed; but, mainly these studies have focused on wired networks. The main purpose of this paper is to provide an optimization framework for optimal virtual network embedding, including a heuristic algorithm with low computational complexity, by explicitly considering the effect of supporting the actual user mobility, assuming the emerging Distributed Mobility Management (DMM) scheme as well as a traditional Centralized Mobility Management (CMM) scheme. In addition to that, service differentiation is introduced, giving higher priority to time-critical over-the-top (OTT) services compared to more traditional elastic Internet applications. The performance of the proposed framework is compared to mobility agnostic greedy algorithms as well as virtual network embedding algorithms from the literature. Numerical investigations reveal that the effect of user mobility has a significant impact on the design of virtual networks. Additionally, the mobility aware scheme can provide tangible gains in the overall performance compared with the previous proposed schemes that do not take explicitly into account the effect of user mobility.
Auteurs: Giorgos Chochlidakis;Vasilis Friderikos;
Apparue dans: IEEE Transactions on Mobile Computing
Date publication: 05.-2017, volume: 16, issue:5, pages: 1343 - 1356
Editeur: IEEE
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» Model-Free Optimal Control Based Intelligent Cruise Control with Hardware-in-the-Loop Demonstration [Research Frontier]
Résumé:
It is difficult to implement optimal control for a system whose model is unknown and operation environment is uncertain, such as the intelligent cruise control of vehicles. This article will address the problem from the perspective of reinforcement learning by learning the optimal policy from the state transition data. The model-free optimal control algorithm is employed to approximate the optimal control policy for the intelligent cruise control system, which considers the comfort performance and the safety performance comprehensively by setting up a total performance index. The algorithm is implemented by two multi-layer neural networks which are the critic network and the actor network. The critic and actor networks are employed to approximate the stateaction value function and the control action, respectively. In addition, a data collecting strategy is proposed to obtain the state transition data distributed uniformly in the state action space from the running trajectory of the host car. The critic network and the action network are trained alternatively by the collected data until converging. The convergent action network is used to obtain the optimal control policy. At last, the policy is tested on a hardware-in-the-loop simulator built upon dSPACE by comparing with a linear quadratic regulator (LQR) controller and a proportion integration differentiation (PID) controller. Results show its excellent performance on both aspects of the safety and the comfort.
Auteurs: Dongbin Zhao;Zhongpu Xia;Qichao Zhang;
Apparue dans: IEEE Computational Intelligence Magazine
Date publication: 05.-2017, volume: 12, issue:2, pages: 56 - 69
Editeur: IEEE
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» Modeling and Characterization of Vertical GaN Schottky Diodes With AlGaN Cap Layers
Résumé:
A new gallium nitride (GaN) Schottky device structure suitable for power electronic applications is discussed. A GaN Schottky diode with an ultrathin AlGaN cap layer was fabricated using an Ni/Au metal stack as the Schottky electrode. ${C}$ ${V}$ measurements at various temperatures were used to calculate a barrier height of 0.65 V with a free electron concentration of $5 times 10^{15}$ cm $^{-3}$ both of which appear temperature independent. A forward conduction model based on a thermionic emission–diffusion process with tunneling through the AlGaN barrier was developed and compared favorably to experimental data. A reverse conduction model utilizing thermionic field emission (TFE) with a triangular energy barrier is presented and then improved upon with a scaling factor that modifies the barrier thickness. This TFE model compares more favorably with the experimental data than the standard thermionic emission model typically used in Schottky diodes. Both the forward conduction and reverse conduction characteristics were assessed at room temperature and elevated temperature. The model can be used to predict how the physical parameters of the device affect its ${I}$ ${V}$ characteristics.
Auteurs: Michael R. Hontz;Yu Cao;Mary Chen;Ray Li;Austin Garrido;Rongming Chu;Raghav Khanna;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 05.-2017, volume: 64, issue:5, pages: 2172 - 2178
Editeur: IEEE
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» Modeling and Parameter Extraction of CMOS On-Chip Spiral Inductors With Ground Shields
Résumé:
A new simple $pi $ -equivalent model with parameter extraction method is presented in this letter, to develop accurate models for spiral inductors on low-resistance CMOS substrate with ground shield structure. C-L-R network is introduced to model the ground loop in the lower metal strips, replacing the conventional C-R-C network. This model contains only ten frequency-independent components with explicit physical meaning, which has fewer elements and is easy to be extracted. Frequency responses of the extracted results are in excellent agreement with the measurements and EM simulations of inductors with different ground shields and layout designs up to 40 GHz. This proves the validity of the proposed model and parameter extraction method. Finally, extracted results of the inductors with different ground shields are compared and investigated.
Auteurs: Bowen Ding;Shengyue Yuan;Chen Zhao;Tong Tian;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 05.-2017, volume: 27, issue:5, pages: 431 - 433
Editeur: IEEE
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» Modeling Nanoelectromechanical Switches With Random Surface Roughness
Résumé:
Surface roughness is an important physical feature of nanometer-scale electromechanical (NEM) devices but typically is not considered in their numerical analysis. In this paper, computer simulations of a single-pole double-throw NEM switch with surface roughness are presented. Roughness is shown to modify the eigenfrequencies of the system, and also to make it possible for the switch to not close successfully. The importance of avoiding a free-standing cantilever is demonstrated.
Auteurs: Daniel Connelly;Tsu-Jae King Liu;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 05.-2017, volume: 64, issue:5, pages: 2409 - 2416
Editeur: IEEE
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» Modeling of CMOS Devices and Circuits on Flexible Ultrathin Chips
Résumé:
The field of flexible electronics is rapidly evolving. The ultrathin chips are being used to address the high-performance requirements of many applications. However, simulation and prediction of changes in response of device/circuit due to bending induced stress remains a challenge as of lack of suitable compact models. This makes circuit designing for bendable electronics a difficult task. This paper presents advances in this direction, through compressive and tensile stress studies on transistors and simple circuits such as inverters with different channel lengths and orientations of transistors on ultrathin chips. Different designs of devices and circuits in a standard CMOS 0.18- $mu text{m}$ technology were fabricated in two separated chips. The two fabricated chips were thinned down to $20~mu text{m}$ using standard dicing-before-grinding technique steps followed by post-CMOS processing to obtain sufficient bendability (20-mm bending radius, or 0.05% nominal strain). Electrical characterization was performed by packaging the thinned chip on a flexible substrate. Experimental results show change of carrier mobilities in respective transistors, and switching threshold voltage of the inverters during different bending conditions (maximum percentage change of 2% for compressive and 4% for tensile stress). To simulate these changes, a compact model, which is a combination of mathematical equations and extracted parameters from BSIM4, has been developed in Verilog-A and compiled into Cadence Virtuoso environment. The proposed model predicts the mobility variations and threshold voltage in compressive and tensile bending stress conditions and orientations, and shows an agreement with the experimental measurements (1% for compressive and 0.6- ; for tensile stress mismatch).
Auteurs: Anastasios Vilouras;Hadi Heidari;Shoubhik Gupta;Ravinder Dahiya;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 05.-2017, volume: 64, issue:5, pages: 2038 - 2046
Editeur: IEEE
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» Modeling of FinFET Parasitic Source/Drain Resistance With Polygonal Epitaxy
Résumé:
In this paper, we introduce a new compact model of the parasitic resistance of a FinFET with a hexagonal-shaped raised source–drain (S/D) structure. In contrast to previous models that divided the extrinsic S/D region into three parts, we redefined the region boundaries and modeled them as a series connection of accumulation resistance, gradient resistance, bulk resistance, and contact resistance. The newly added bulk resistance model accounts for the highly doped silicon region. We also significantly improved the contact resistance model to reflect the contact area and contact resistivity for better accuracy in the raised S/D region. We validated the accuracy of our model by varying the gate voltage, doping diffusion length, epitaxy silicon height, and contact resistivity, finding the model errors to be within 2% of the 3-D technology CAD device simulation results.
Auteurs: JungHun Kim;Hai Au Huynh;SoYoung Kim;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 05.-2017, volume: 64, issue:5, pages: 2072 - 2079
Editeur: IEEE
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» Modeling of the Change of Impedance of an Eddy Current Probe Due to Small Changes in Host Conductivity
Résumé:
Two different approximation techniques for predicting the response of an eddy current coil in the presence of small changes in conductivity were developed. The small changes in conductivity are the result of changes in the orientation of individual anisotropic crystals in a polycrystalline aggregate. Orientation information from electron backscatter diffraction was imported directly into the modeling domain and the simulations were run to map orientations into an approximated eddy current response. These approximated responses were compared with experimental data obtained with commercially available eddy current equipment, and the approximations were found to be in good agreement with experiment. Further verification was performed with other existing numerical and analytical models to demonstrate the accuracy of the approximations made in deriving the eddy current response. This paper shows these results and demonstrates the viability of using low-fidelity approximations in predicting the eddy current response when the change in conductivity is low.
Auteurs: Matthew R. Cherry;Shamachary Sathish;Ryan D. Mooers;Adam L. Pilchak;Ramana Grandhi;
Apparue dans: IEEE Transactions on Magnetics
Date publication: 05.-2017, volume: 53, issue:5, pages: 1 - 10
Editeur: IEEE
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» Modeling of Via Resistance for Advanced Technology Nodes
Résumé:
We investigate the dependence of Cu via resistance on via dimensions, shape, misalignment, and Co via prefill level by means of a novel resistivity model, calibrated to actual wires on silicon and integrated into the Synopsys Raphael tool. For this paper, we consider the case of 16 and 12nm self-aligned vias, which are representative for the 7 and 5nm logic technology nodes, respectively. Process emulations are performed by using the Synopsys Sentaurus Process Explorer tool in order to generate 3-D models of the investigated via structures. Finally, via resistance is extracted through current simulations in Raphael, that is, by taking into account the actual conductive path from the wires into the via. We predict that via resistance could increase by more than a factor of 2 from node to node. We show that chamfered vias can exhibit up to 56% less resistance than standard (87° tapered) vias because of the larger cross section at the via top. For the same reason, via resistance sensitivity to via width variations along the direction of the connecting (i.e. upper) wire is smaller for chamfered vias. As far as via misalignment to the connected (i.e. lower) wire is concerned, we demonstrate that in the range of interest, the induced resistance increase is not severe (e.g. 20% or lower), and in particular, via resistance is not inversely proportional to the contact area between the via and the connected wire. If side contact to the connected wire is enabled upon misalignment, the via resistance increase is further reduced. If vias are fully self-aligned, that is, self-aligned to both connecting and connected wires, the impact of misalignment can be neutralized in a certain range by properly oversizing the via mask in the direction along the connecting wire. Finally, we show that Co via prefill can enable a substantial reduction (up to 45%) of via resistance for chamfered vias, where the bottom ba- rier surface can be significantly increased when raised to the via top by means of the prefill step.
Auteurs: Ivan Ciofi;Philippe J. Roussel;Yves Saad;Victor Moroz;Chia-Ying Hu;Rogier Baert;Kristof Croes;Antonino Contino;Kevin Vandersmissen;Weimin Gao;Philippe Matagne;Mustafa Badaroglu;Christopher J. Wilson;Dan Mocuta;Zsolt Tőkei;
Apparue dans: IEEE Transactions on Electron Devices
Date publication: 05.-2017, volume: 64, issue:5, pages: 2306 - 2313
Editeur: IEEE
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» Modeling, Simulation, and Comparison of Control Techniques for Energy Storage Systems
Résumé:
This paper describes the modeling and formulation of a variety of deterministic techniques for energy storage devices, namely the PI, H-infinity, and sliding mode controllers. These techniques are defined based on a general, yet detailed, energy storage device model, which is accurate for transient stability analysis. The paper also presents a thorough statistical comparison of the performance and robustness of the considered control techniques, using stochastic dynamic models and a variety of disturbances and scenarios. The case study is based on a 1479-bus model of the all-island Irish transmission system and an energy storage device actually installed in the system.
Auteurs: Álvaro Ortega;Federico Milano;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 2445 - 2454
Editeur: IEEE
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» Modernizing the Grid: Challenges and Opportunities for a Sustainable Future
Résumé:
In Addition To Their Age, Particularly in large metropolitan areas, electric power systems throughout the industrialized world face challenges brought on by new technology trends, environmental concerns, evolving weather patterns, a multiplicity of consumer needs, and regulatory requirements. New technology trends include the development of more efficient, reliable, and cost-effective renewable generation and distributed energy resources (DERs), energy storage technologies, and electric vehicles (EVs), along with monitoring, protection, automation, and control devices and communications that offer significant opportunities for realizing a sustainable energy future. The medium- to long-term vision for the electrical grid is to transition away from carbon-based fuels toward increased penetration of renewable DERs and use of energy storage and electric transportation.
Auteurs: Julio Romero Aguero;Erik Takayesu;Damir Novosel;Ralph Masiello;
Apparue dans: IEEE Power and Energy Magazine
Date publication: 05.-2017, volume: 15, issue:3, pages: 74 - 83
Editeur: IEEE
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» Morphing Origami Conical Spiral Antenna Based on the Nojima Wrap
Résumé:
A two-arm Nojima origami conical spiral antenna (CSA) is designed. The antenna is based on the origami Nojima wrap pattern that enables the antenna to morph from a planar dipole to a conical spiral. The design equations of the Nojima origami CSA are presented and its performance is studied using simulations and measurements. The reflection coefficient, input impedance, gain, and axial ratio of this antenna are investigated over a wide frequency band. The radiation patterns of this antenna are also examined. A prototype of an origami Nojima CSA with 1.5 turns is manufactured and measured.
Auteurs: Shun Yao;Xueli Liu;Stavros V. Georgakopoulos;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2222 - 2232
Editeur: IEEE
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» Morphology, Structure, and Gas Sensing Performance of Conductive Polymers and Polymer/Carbon Black Composites Used for Volatile Compounds Detection
Résumé:
In this paper, we present fabrication, characterization, and sensing performance of four sensor elements, including two conducting polymers (polypyrrole and polyaniline), and two polymer/carbon black (CB) composites consisting ethyl cellulose (EC) and poly(caprolactone) (PCL). The identifications of four different vapors (methanol, ethanol, acetone, and ammonia) by these four sensors have been successfully demonstrated by using the principal component analysis. The sensing mechanisms of the examined sensors were investigated and a discussion on the similarity of gas sensor responses and the creep behavior has also been given. It was found that the response/recovery behavior of gas sensors can be presented by the Kelvin–Voigt rheological model. The effect of CB content on polymer/carbon sensor performance was investigated in the range of 15–20 wt. %. The increase of CB wt. %, led to increase the sensor response. The morphology of the produced EC/CB and PCL/CB composite sensors has been characterized by scanning electron microscopy and atomic force microscopy. Polyaniline indicated the highest response to ammonia due to effect of ${p}$ -phenylene resonance on deprotonation process. The PCL/CB sensor response was more pronounced as compared with EC/CB, due to its higher porous structure.
Auteurs: Farnoosh Miramirkhani;Amir H. Navarchian;
Apparue dans: IEEE Sensors Journal
Date publication: 05.-2017, volume: 17, issue:10, pages: 2992 - 3000
Editeur: IEEE
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» Motion and Switching of Dual-Vortex Cores in Elliptical Permalloy Nanodisk Stimulated by a Gaussian Magnetic Field Pulse
Résumé:
Magnetic nanostructures have potential applications in ultrahigh-density magnetic storage. In this paper, the dynamics of the dual magnetic vortices in elliptical Permalloy nanodisk are investigated using micromagnetic modeling. Under the stimulation of the short-axis ( $y$ -axis) Gaussian field pulse and long-axis ( $x$ -axis) constant field, the equilibrium positions of dual-vortex cores can be driven away from the initial positions. The displacement in the $y$ -direction is proportional to the magnitude of the $x$ -axis constant field. The displacement in the $x$ -direction exhibit periodic reliance on the pulsewidth of the $y$ -axis Gaussian field pulse. The threshold value of pulse strength for dual-vortex motion increases with the magnitude of the $x$ -axis constant field. The mechanism of polarity and chirality switching in dual-vortex cores are studied through analyzing the trajectories of vortex cores in the annihilation and nucleation processes. The switching of polarity exhibits an oscillatory dependence on the pulsewidth and strength. The minimum pulse strength required for chirality switching is 120 mT, while the corresponding pulsewidth is influenced by the $x$ -axis constant field. This paper provides insights on the magnetization dynamics of nanostructures containing dual vortices subject to external excitations.
Auteurs: X. Li;Y. Zhou;T. Zeng;K. -W. Lin;P. T. Lai;Philip W. T. Pong;
Apparue dans: IEEE Transactions on Magnetics
Date publication: 05.-2017, volume: 53, issue:5, pages: 1 - 6
Editeur: IEEE
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» Motion Classification-Based Fast Motion Estimation for High-Efficiency Video Coding
Résumé:
High efficiency video coding (HEVC), the latest video coding standard, is becoming popular due to its excellent coding performance. However, the significant gain in performance is achieved at the cost of substantially higher encoding complexity than its precedent H.264/AVC, in which motion estimation (ME) is the most time-consuming module that effectively removes temporal redundancy. Test zone search (TZS) is adopted as the default fast ME method in the reference software of HEVC; however, its computational complexity is still too high for real-time applications. Several fast ME algorithms have been recently proposed to further reduce ME complexity; however, these approaches typically lead to non-negligible performance loss. To address this problem, this paper proposes a motion classification-based fast ME algorithm. By exploring the motion relationship of neighboring blocks and the coding cost characteristic, the prediction unit (PU) is first categorized into one of three classes, namely, motion-smooth PU, motion-medium PU and motion-complex PU. Then different search strategies are carefully designed for PUs of each class according to their respective motion and content characteristics. Furthermore, a fast search priority-based partial internal termination scheme is presented to rapidly skip impossible positions that speeds up cost computation during the ME process. Extensive experimental results demonstrate that the proposed algorithm achieves as much as 12.47% and 20.25% reductions in total encoder complexity when compared with TZS under low delay P and random access configuration, respectively, with negligible rate-distortion degradation; thus, it outperforms state-of-the-art fast ME algorithms in terms of both coding performance and complexity reduction.
Auteurs: Rui Fan;Yongfei Zhang;Bo Li;
Apparue dans: IEEE Transactions on Multimedia
Date publication: 05.-2017, volume: 19, issue:5, pages: 893 - 907
Editeur: IEEE
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» MoZo: A Moving Zone Based Routing Protocol Using Pure V2V Communication in VANETs
Résumé:
Vehicular Ad-hoc Networks (VANETs) are an emerging field, whereby vehicle-to-vehicle communications can enable many new applications such as safety and entertainment services. Most VANET applications are enabled by different routing protocols. The design of such routing protocols, however, is quite challenging due to the dynamic nature of nodes (vehicles) in VANETs. To exploit the unique characteristics of VANET nodes, we design a moving-zone based architecture in which vehicles collaborate with one another to form dynamic moving zones so as to facilitate information dissemination. We propose a novel approach that introduces moving object modeling and indexing techniques from the theory of large moving object databases into the design of VANET routing protocols. The results of extensive simulation studies carried out on real road maps demonstrate the superiority of our approach compared with both clustering and non-clustering based routing protocols.
Auteurs: Dan Lin;Jian Kang;Anna Squicciarini;Yingjie Wu;Sashi Gurung;Ozan Tonguz;
Apparue dans: IEEE Transactions on Mobile Computing
Date publication: 05.-2017, volume: 16, issue:5, pages: 1357 - 1370
Editeur: IEEE
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» MPPT in Wireless Sensor Nodes Supply Systems Based on Electromagnetic Vibration Harvesters for Freight Wagons Applications
Résumé:
The starting point for the proper design of an efficient wireless sensor node (WSN) supply system that is based on the adoption of a resonant electromagnetic vibration energy harvester (REVEH) is represented by the choice of a REVEH with a proper resonance frequency. But further likewise important design guidelines need to be also taken into account especially if, as in the case of freight wagons applications, vibrations are nonsinusoidal and their characteristics change with time. In this paper, the guidelines leading to the development of a smart power electronics interface between the REVEH and the WSN are provided with reference to freight wagons applications. In particular, for the most widely used double stage ac/dc architecture for REVEH applications, such guidelines not only allow the choice of the proper dc/dc converter topology, but they also allow the development of a suitable maximum power point tracking control strategy that allows to avoid the waste of energy and the consequent necessity to oversize the REVEH.
Auteurs: Marco Balato;Luigi Costanzo;Massimo Vitelli;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3576 - 3586
Editeur: IEEE
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» MRCP-RM: A Technique for Resource Allocation and Scheduling of MapReduce Jobs with Deadlines
Résumé:
Resource allocation and scheduling on clouds are required to harness the power of the underlying resource pool such that the service provider can meet the quality of service requirements of users, which are often captured in service level agreements (SLAs). This paper focuses on resource allocation and scheduling on clouds and clusters that process MapReduce jobs with SLAs. The resource allocation and scheduling problem is modelled as an optimization problem using constraint programming, and a novel MapReduce Constraint Programming based Resource Management algorithm (MRCP-RM) is devised that can effectively process an open stream of MapReduce jobs where each job is characterized by an SLA comprising an earliest start time, a required execution time, and an end-to-end deadline. A detailed performance evaluation of MRCP-RM is conducted for an open system subjected to a stream of job arrivals using both simulation and experimentation on a real system. The experiments on a real system are performed on a Hadoop cluster (deployed on Amazon EC2) that runs our new Hadoop Constraint Programming based Resource Management algorithm (HCP-RM) that incorporates a technique for handling data locality. The results of the performance evaluation demonstrate the effectiveness of MRCP-RM/HCP-RM in generating a schedule that leads to a low proportion of jobs missing their deadlines (P) and also provide insights into system behaviour and performance. In the simulation experiments, it is observed that MRCP-RM achieves on average an 82 percent lower P compared to a technique from the existing literature when processing a synthetic workload from Facebook. Furthermore, in the experiments performed on a Hadoop cluster deployed on Amazon EC2, it is observed that HCP-RM achieved on average a 63 percent lower P compared to an EDF-Scheduler for a wide variety of workload and system parameters experimented with.
Auteurs: Norman Lim;Shikharesh Majumdar;Peter Ashwood-Smith;
Apparue dans: IEEE Transactions on Parallel and Distributed Systems
Date publication: 05.-2017, volume: 28, issue:5, pages: 1375 - 1389
Editeur: IEEE
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» Multi-Bit Flipping Decoding of LDPC Codes for NAND Storage Systems
Résumé:
This letter presents a new multi-bit flipping decoding algorithm for low-density parity-check codes, which can enhance hard-information-based decoding performance for NAND storage systems. Since the conventional enhancement techniques developed for bit-flipping decoding require soft information, the long latency taken to generate the soft information, makes it hard to apply them to practical NAND storage systems. The proposed algorithm requires only hard information and achieves the better performance than previous hard-information-based algorithms. The proposed method flips multiple bits in each iteration, but the maximum number of bits to be flipped in an iteration is restricted to prevent overcorrection. To relax the hardware complexity of sorting, in addition, an efficient approximation method is proposed, reducing the hardware complexity of a 512-input sorter by 48.3% without degrading the performance noticeably.
Auteurs: Jaehwan Jung;In-Cheol Park;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 979 - 982
Editeur: IEEE
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» Multi-Hop Cooperative Relaying With Energy Harvesting From Cochannel Interferences
Résumé:
A novel multi-hop cooperative relaying transmission is proposed, where neither the source nor the relays have constant power supplies but rather scavenge energy from cochannel interferences (CCIs) and then use it for subsequent data transmission. The results show that, larger CCIs, usually detrimental to system performance, offer higher transmit power to each node and benefit improving system performance. Given a prescribed end-to-end (e2e) outage threshold, this letter identifies the largest number of hops that energy harvesting from CCIs can support. Moreover, the e2e outage probability is shown to be dominated by the quality of the desired channels along with the relaying link, almost regardless of the CCIs.
Auteurs: Erhu Chen;Minghua Xia;Daniel B. da Costa;Sonia Aïssa;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1199 - 1202
Editeur: IEEE
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» Multi-Indenter Device for in Vivo Biomechanical Tissue Measurement
Résumé:
Biomechanical tissue properties have been hypothesized to play a critical role in the quantification of prosthetic socket production for individuals with limb amputation. In this investigation, a novel indenter platform is presented and its performance evaluated for the purposes of residual-limb tissue characterization. The indenter comprised 14 position- and force-controllable actuators that circumferentially surround a biological residuum to form an actuator ring. Each indenter actuator was individually controllable in position ( ${{97.1}}~mu {text {m}}$ accuracy) and force (330 mN accuracy) at a PC controller feedback rate of 500 Hz, allowing for a range of measurement across a residual stump. Data were collected from 162 sensors over an EtherCAT fieldbus to characterize the mechanical hyperviscoelastic tissue response of two transtibial residual-limbs from a study participant with bilateral amputations. At five distinct anatomical locations across the residual-limb, force versus deflection data—including hyperviscoelastic tissue properties—are presented, demonstrating the accuracy and versatility of the multi-indenter platform for residual-limb tissue characterization.
Auteurs: Arthur Petron;Jean-François Duval;Hugh Herr;
Apparue dans: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Date publication: 05.-2017, volume: 25, issue:5, pages: 426 - 435
Editeur: IEEE
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» Multi-Level Random Walk for Software Test Suite Reduction
Résumé:
Software testing is important and time-consuming. A test suite, i.e., a set of test cases, plays a key role in validating the expected program behavior. In modern test-driven development, a test suite pushes the development progress. Software evolves over time; its test suite is executed to detect whether a new code change adds bugs to the existing code. Executing all test cases after each code change is unnecessary and may be impossible due to the limited development cycle. On the one hand, multiple test cases may focus on an identical piece of code; then several test cases cannot detect extra bugs. On the other hand, even executing a test suite once in a large project takes around one hour [1]; frequent code changes require much time for conducting testing. For instance, in Hadoop, a framework of distributed computing, 2,847 version commits are accepted within one year from September 2014 with a peak of 135 commits in one week [2].
Auteurs: Zongzheng Chi;Jifeng Xuan;Zhilei Ren;Xiaoyuan Xie;He Guo;
Apparue dans: IEEE Computational Intelligence Magazine
Date publication: 05.-2017, volume: 12, issue:2, pages: 24 - 33
Editeur: IEEE
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» Multi-Linear Probabilistic Energy Flow Analysis of Integrated Electrical and Natural-Gas Systems
Résumé:
The deep interdependence between electrical and gas systems entails a potential threat to the security (or reliability) of both systems. It is imperative to investigate the impacts of massive uncertainties on the overall secure and economical operation of both systems. In this paper, a probabilistic energy flow framework of integrated electrical and gas systems is initially proposed considering correlated varying energy demands and wind power. Three aspects of couplings between electrical and gas systems are considered: gas-fired generators, electric-driven compressors, and energy hubs integrated with power to gas (P2G) units. Furthermore, a multilinear method is specially designed to produce a deterministic energy flow solution for each sample generated by Monte Carlo simulation (MCS). Finally, test results have verified that the proposed multilinear MCS method prevails over the nonlinear MCS. In addition, P2G effectively benefits the operation of both electrical and gas networks.
Auteurs: Sheng Chen;Zhinong Wei;Guoqiang Sun;Kwok W. Cheung;Yonghui Sun;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 1970 - 1979
Editeur: IEEE
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» Multi-Scenario Parameter Estimation for Synchronous Generation Systems
Résumé:
Parameter estimation of synchronous generation systems is vital to the validation of power system dynamic analysis. Compared with the substantially investigated single-scenario parameter estimation, multi-scenario estimation is more advantageous in terms of estimation accuracy. This study proposes a systematic method for solving the challenges of implementing multi-scenario parameter estimation through four crucial steps. First, a novel method using trajectory sensitivity is proposed for multi-scenario parameter identifiability analysis. Scenarios are then ranked based on the scenario identifiability index with respect to the identifiable parameters. Third, a scenario decomposition strategy is developed by using the reduced-space interior point method to accelerate the parameter estimation procedure. Finally, a method based on Chi-square test is proposed for bad scenario detection and identification. In the case study, numerical experiments and field measurements are used to validate the effectiveness of the proposed method.
Auteurs: Zexiang Zhu;Guangchao Geng;Quanyuan Jiang;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 1851 - 1859
Editeur: IEEE
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» Multiband and Broadband Wireless Power Transfer Systems Using the Conformal Strongly Coupled Magnetic Resonance Method
Résumé:
Novel multiband and broadband wireless power transfer (WPT) systems based on conformal strongly coupled magnetic resonance (CSCMR) are presented in this paper. An analytical model for CSCMR systems is developed in order to study their performance. Optimal multiband and broadband CSCMR systems are designed and their performance is validated using simulations and measurements. A broadband CSCMR system, which exhibits seven times broader bandwidth than conventional SCMR and CSCMR systems operating at the same frequency, is designed and prototyped.
Auteurs: Hao Hu;Stavros V. Georgakopoulos;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3595 - 3607
Editeur: IEEE
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» Multidimensional Optical Sensing and Imaging System (MOSIS): From Macroscales to Microscales
Résumé:
Multidimensional optical imaging systems for information processing and visualization technologies have numerous applications in fields such as manufacturing, medical sciences, entertainment, robotics, surveillance, and defense. Among different three-dimensional (3-D) imaging methods, integral imaging is a promising multiperspective sensing and display technique. Compared with other 3-D imaging techniques, integral imaging can capture a scene using an incoherent light source and generate real 3-D images for observation without any special viewing devices. This review paper describes passive multidimensional imaging systems combined with different integral imaging configurations. One example is the integral-imaging-based multidimensional optical sensing and imaging systems (MOSIS), which can be used for 3-D visualization, seeing through obscurations, material inspection, and object recognition from microscales to long range imaging. This system utilizes many degrees of freedom such as time and space multiplexing, depth information, polarimetric, temporal, photon flux and multispectral information based on integral imaging to record and reconstruct the multidimensionally integrated scene. Image fusion may be used to integrate the multidimensional images obtained by polarimetric sensors, multispectral cameras, and various multiplexing techniques. The multidimensional images contain substantially more information compared with two-dimensional (2-D) images or conventional 3-D images. In addition, we present recent progress and applications of 3-D integral imaging including human gesture recognition in the time domain, depth estimation, mid-wave-infrared photon counting, 3-D polarimetric imaging for object shape and material identification, dynamic integral imaging implemented with liquid-crystal devices, and 3-D endoscopy for healthcare applications.
Auteurs: Bahram Javidi;Xin Shen;Adam S. Markman;Pedro Latorre-Carmona;Adolfo Martínez-Uso;José Martinez Sotoca;Filiberto Pla;Manuel Martínez-Corral;Genaro Saavedra;Yi-Pai Huang;Adrian Stern;
Apparue dans: Proceedings of the IEEE
Date publication: 05.-2017, volume: 105, issue:5, pages: 850 - 875
Editeur: IEEE
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» Multifrequency Radar Imagery and Characterization of Hazardous and Noxious Substances at Sea
Résumé:
The increase in maritime traffic, particularly the transport of hazardous and noxious substances (HNSs), requires advanced methods of identification and characterization in environmental chemical spills. Knowledge about HNS monitoring using radar remote sensing is not as extensive as for oil spills; however, any progress on this issue would likely advance the monitoring of both chemical and oil-related incidents. To address the need for HNS monitoring, an experiment was conducted in May 2015 over the Mediterranean Sea during which controlled releases of HNS were imaged by a multifrequency radar system. The aim of this experiment was to establish a procedure for collecting evidence of illegal maritime pollution by noxious liquid substances using airborne radar sensors. In this paper, we demonstrate the ability of radar imagery to detect and characterize chemicals at sea. A normalized polarization difference parameter is introduced to quantify both the impacts of released product on the ocean surface and the relative concentration of the substance within the spill. We show that radar imagery can provide knowledge of the involved HNS. In particular, one can distinguish a product that forms a film on the top of the sea surface from another that mixes with seawater, the information that is critical for efficient cleanup operations.
Auteurs: Sébastien Angelliaume;Brent Minchew;Sophie Chataing;Philippe Martineau;Véronique Miegebielle;
Apparue dans: IEEE Transactions on Geoscience and Remote Sensing
Date publication: 05.-2017, volume: 55, issue:5, pages: 3051 - 3066
Editeur: IEEE
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» Multimodal Imaging Based on Digital Holography
Résumé:
Digital holography provides a method of the 3-D recording and numerical reconstruction by a simple optical system and a computer. Quantitative measurement and numerical refocusing are major characteristics. So far, many physical parameters such as amplitude, phase, polarization, fluorescence, and spectra can be obtained independently. Recently, multimodal imaging that can obtain simultaneously two or more physical parameters by combining digital holographic microscope and other optical microscopes such as a fluorescence optical microscope and a Raman scattering microscope has emerged. In this review, physical parametric imaging techniques based on digital holography are presented and then these techniques are enhanced to develop multimodal imaging based on digital holography.
Auteurs: Osamu Matoba;Xiangyu Quan;Peng Xia;Yasuhiro Awatsuji;Takanori Nomura;
Apparue dans: Proceedings of the IEEE
Date publication: 05.-2017, volume: 105, issue:5, pages: 906 - 923
Editeur: IEEE
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» Multimodal KB Harvesting for Emerging Spatial Entities
Résumé:
New entities are being created daily. Though the novelty of these entities naturally attracts mentions, due to lack of prior knowledge, it is more challenging to collect knowledge about such entities than pre-existing entities, whose KBs are comprehensively annotated through LBSNs and EBSNs. In this paper, we focus on knowledge harvesting for emerging spatial entities (ESEs), such as new businesses and venues, assuming we have only a list of ESE names. Existing techniques for knowledge base (KB) harvesting are primarily associated with information extraction from textual corpora. In contrast, we propose a multimodal method for event detection based on the complementary interaction of image, text, and user information between multi-source platforms, namely Flickr and Twitter. We empirically validate our harvesting approaches improve the quality of KB with enriched place and event knowledge.
Auteurs: Jinyoung Yeo;Hyunsouk Cho;Jin-Woo Park;Seung-Won Hwang;
Apparue dans: IEEE Transactions on Knowledge and Data Engineering
Date publication: 05.-2017, volume: 29, issue:5, pages: 1073 - 1086
Editeur: IEEE
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» Multiobjective Beampattern Optimization in Collaborative Beamforming via NSGA-II With Selective Distance
Résumé:
Collaborative beamforming is usually characterized by high, asymmetrical sidelobe levels due to the randomness of node locations. Previous works have shown that the optimization methods aiming to reduce the peak sidelobe level (PSL) alone do not guarantee the overall sidelobe reduction of the beampattern, especially when the nodes are random and cannot be manipulated. Hence, this paper proposes a multiobjective amplitude and phase optimization technique with two objective functions: PSL minimization and directivity maximization, in order to improve the beampattern. A novel selective Euclidean distance approach in the nondominated sorting genetic algorithm II (NSGA-II) is proposed to steer the candidate solutions toward a better solution. Results obtained by the proposed NSGA with selective distance (NSGA-SD) are compared with the single-objective PSL optimization performed using both GA and particle swarm optimization. The proposed multiobjective NSGA provides up to 40% improvement in PSL reduction and 50% improvement in directivity maximization and up to 10% increased performance compared to the legacy NSGA-II. The analysis of the optimization method when considering mutual coupling between the nodes shows that this improvement is valid when the inter-node Euclidean separations are large.
Auteurs: Suhanya Jayaprakasam;Sharul Kamal Abdul Rahim;Chee Yen Leow;Tiew On Ting;Akaa A. Eteng;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2348 - 2357
Editeur: IEEE
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» Multiobjective Discrete Artificial Bee Colony Algorithm for Multiobjective Permutation Flow Shop Scheduling Problem With Sequence Dependent Setup Times
Résumé:
The multiobjective permutation flow shop scheduling problem with sequence dependent setup times has been an object of investigations for decades. This widely studied problem from the scheduling theory links the sophisticated solution algorithms with the moderate real world applications. This paper presents a novel multiobjective discrete artificial bee colony algorithm based decomposition, called MODABC/D, to solve the sequence dependent setup times multiobjective permutation flowshop scheduling problem with the objective to minimize makespan and total flowtime. First, in order to make the standard artificial bee colony algorithm to solve the scheduling problem, a discrete artificial bee colony algorithm is proposed to solve the problem based on the perturbation operation. Then, a problem-specific solution builder heuristic is used to initialize the population to enhance the quality of the initial solution. Finally, a further local search method are comprised of a single local search procedures based on the insertion neighborhood structures to find the better solution for the nonimproved individual. The performance of the proposed algorithms is tested on the well-known benchmark suite of Taillard. The highly effective performance of the multiobjective discrete artificial bee colony algorithm-based decomposition is compared against the state of art algorithms from the existing literature in terms of both coverage value and hypervolume indicator.
Auteurs: Xiangtao Li;Shijing Ma;
Apparue dans: IEEE Transactions on Engineering Management
Date publication: 05.-2017, volume: 64, issue:2, pages: 149 - 165
Editeur: IEEE
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» Multiple-Frequency DBIM-TwIST Algorithm for Microwave Breast Imaging
Résumé:
A novel distorted Born iterative method (DBIM) algorithm is proposed for microwave breast imaging based on the two-step iterative shrinkage/thresholding method. We show that this implementation is more flexible and robust than using traditional Krylov subspace methods such as the CGLS as solvers of the ill-posed linear problem. This paper presents several strategies to increase the algorithm’s robustness: a hybrid multifrequency approach to achieve an optimal tradeoff between imaging accuracy and reconstruction stability; a new approach to estimate the average breast tissues properties, based on sampling along their range of possible values and running a few DBIM iterations to find the minimum error; and finally, a new regularization strategy for the DBIM method based on the $L^{1}$ norm and the Pareto curve. We present reconstruction examples which illustrate the benefits of these optimization strategies, which have resulted in a DBIM algorithm that outperforms our previous implementations for microwave breast imaging.
Auteurs: Zhenzhuang Miao;Panagiotis Kosmas;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2507 - 2516
Editeur: IEEE
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» Multiport Interferometer-Enabled 2-D Angle of Arrival (AOA) Estimation System
Résumé:
A systematic scheme for finding the direction of arrival (DOA) or 2-D angle of arrival (AOA) of an electromagnetic beam is proposed and demonstrated in this paper. This system estimates the respective angle of propagation vector of an incoming plane wave in either horizontal or vertical plane. It consists of three main parts, namely, an antenna, a multiport wave interferometric receiver or phase discriminator, and a signal processor. The antenna is composed of four receiving elements located in the same plane, which is arranged in a diamond-shaped configuration. The received signals manifest relative phase differences that contain information about the beam’s DOA. With the proposed eight-port junction topology, the interferometer extracts these informative phase differences and leaves them for a simple signal processing algorithm to estimate the two angles. The theoretical analysis of the proposed scheme is presented along with system-level simulation results for the proof of concept. In addition, an appropriate calibration technique is formulated to deal with nonidealities and consecutive errors in practice. One of the main applications of such a system is related to the angular detection of an antenna-to-antenna misalignment in pencil beam millimeter-wave systems. Therefore, implementation of the presented system scheme for millimeter wave applications is briefly discussed for its prototyping over 60-GHz range (V-band). Finally, the performance of the prototype system is assessed through a set of system-level measurements. Excellent results are obtained, thus validating the outstanding functionality of the proposed system. Simplicity, low cost, compact size, and operational accuracy make this system a superior candidate for 2-D angle detection applications.
Auteurs: Jaber Moghaddasi;Tarek Djerafi;Ke Wu;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 05.-2017, volume: 65, issue:5, pages: 1767 - 1779
Editeur: IEEE
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» Multiscale Simulation of Power System Transients Based on the Matrix Exponential Function
Résumé:
Power system electro-magnetic transient programs (EMTP) have been popular among researchers and practitioners due to their detailed component modeling and high simulation accuracy for complex system operations. Despite broad applications in simulations with wide range of timescales, the small discretization step of these programs makes their use very time-consuming for system studies with long time span. Facing the increasingly complex power system transient characteristics and simulation demands, a multiscale algorithm that integrates the simulations of the electromagnetic and slower electromechanical transients is desirable. The multiscale simulation algorithm preserves the high fidelity of the EMTP and attains higher efficiency for the overall transient simulation. In this paper, we achieve this goal by exploiting the unique properties of the matrix exponential function. The proposed algorithm is capable of utilizing large step sizes to speed up the simulation of slow dynamics, whereas the fast transients are accurately reconstructed through efficient dense output mechanism, which is built upon the matrix exponential function computation. Numerical studies including a large-scale wind farm simulation are conducted to demonstrate the effectiveness of the proposed multiscale algorithm.
Auteurs: Chengshan Wang;Xiaopeng Fu;Peng Li;Jianzhong Wu;Liwei Wang;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 1913 - 1926
Editeur: IEEE
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» Multisensor Coupled Spectral Unmixing for Time-Series Analysis
Résumé:
We present a new framework, called multisensor coupled spectral unmixing (MuCSUn), that solves unmixing problems involving a set of multisensor time-series spectral images in order to understand dynamic changes of the surface at a subpixel scale. The proposed methodology couples multiple unmixing problems based on regularization on graphs between the time-series data to obtain robust and stable unmixing solutions beyond data modalities due to different sensor characteristics and the effects of nonoptimal atmospheric correction. Atmospheric normalization and cross calibration of spectral response functions are integrated into the framework as a preprocessing step. The proposed methodology is quantitatively validated using a synthetic data set that includes seasonal and trend changes on the surface and the residuals of nonoptimal atmospheric correction. The experiments on the synthetic data set clearly demonstrate the efficacy of MuCSUn and the importance of the preprocessing step. We further apply our methodology to a real time-series data set composed of 11 Hyperion and 22 Landsat-8 images taken over Fukushima, Japan, from 2011 to 2015. The proposed methodology successfully obtains robust and stable unmixing results and clearly visualizes class-specific changes at a subpixel scale in the considered study area.
Auteurs: Naoto Yokoya;Xiao Xiang Zhu;Antonio Plaza;
Apparue dans: IEEE Transactions on Geoscience and Remote Sensing
Date publication: 05.-2017, volume: 55, issue:5, pages: 2842 - 2857
Editeur: IEEE
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» Multispectral and Hyperspectral Image Fusion Using a 3-D-Convolutional Neural Network
Résumé:
In this letter, we propose a method using a 3-D convolutional neural network to fuse together multispectral and hyperspectral (HS) images to obtain a high resolution HS image. Dimensionality reduction of the HS image is performed prior to fusion in order to significantly reduce the computational time and make the method more robust to noise. Experiments are performed on a data set simulated using a real HS image. The results obtained show that the proposed approach is very promising when compared with conventional methods. This is especially true when the HS image is corrupted by additive noise.
Auteurs: Frosti Palsson;Johannes R. Sveinsson;Magnus O. Ulfarsson;
Apparue dans: IEEE Geoscience and Remote Sensing Letters
Date publication: 05.-2017, volume: 14, issue:5, pages: 639 - 643
Editeur: IEEE
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» Multistage Robust Unit Commitment With Dynamic Uncertainty Sets and Energy Storage
Résumé:
The deep penetration of wind and solar power is a critical component of the future power grid. However, the intermittency and stochasticity of these renewable resources bring significant challenges to the reliable and economic operation of power systems. Motivated by these challenges, we present a multistage adaptive robust optimization model for the unit commitment (UC) problem, which models the sequential nature of the dispatch process and utilizes a new type of dynamic uncertainty sets to capture the temporal and spatial correlations of wind and solar power. The model also considers the operation of energy storage devices. We propose a simplified and effective affine policy for dispatch decisions, and develop an efficient algorithmic framework using a combination of constraint generation and duality-based reformulation with various improvements. Extensive computational experiments show that the proposed method can efficiently solve multistage robust UC problems on the Polish 2736-bus system under high dimensional uncertainty of 60 wind farms and 30 solar farms. The computational results also suggest that the proposed model leads to significant benefits in both costs and reliability over robust models with traditional uncertainty sets as well as deterministic models with reserve rules.
Auteurs: Álvaro Lorca;Xu Andy Sun;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 1678 - 1688
Editeur: IEEE
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» Mutual Outage Probability
Résumé:
The performance of any multiuser wireless communications system is strongly affected by interference. Consequently, the design of such systems must comply with some outage probability criteria. Although interference occurs in a mutual entangled basis, with wireless devices interfering with each other, outage is commonly considered on an individual per-device basis. This approach, however, is a simplified solution to a more intricate multidimensional and system-wide problem, in which several mutually interfering devices may be experiencing an outage simultaneously. The true outage probability across several devices is given by a set of mutual entangled boundary conditions to be fulfilled. This paper presents useful novel formulations for outage probability in multiuser wireless settings, here named mutual outage probability (MOP), for the interference-limited environment. Several scenarios are envisaged, in which some signals are in outage, whereas others are not and still for some others these conditions are irrelevant, all at the same time. We introduce a general framework for calculating the MOP, and present closed-form formulas for the Rayleigh case. Finally, we illustrate the practical use of these formulations in a call admission control application.
Auteurs: Flavio du Pin Calmon;Álvaro Augusto Machado de Medeiros;Michel Daoud Yacoub;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 05.-2017, volume: 16, issue:5, pages: 3138 - 3150
Editeur: IEEE
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» My Best Decision [Memoirs]
Résumé:
Reports on the author's work with the IEEE P1584 Working Group to make the workplace a safer place.
Auteurs: Wei-Jen Lee;
Apparue dans: IEEE Industry Applications Magazine
Date publication: 05.-2017, volume: 23, issue:3, pages: 80 - 80
Editeur: IEEE
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» My First Lecture and Other Lessons in Teaching
Résumé:
I recently started teaching a course on programmable system-on-chip design for senior undergraduates and full-time and parttime master's degree students. The undergraduate students come from the Bachelor in Computer Engineering program while the master's degree students are in the Master in Embedded Systems program. At the time you are reading this article, it will have been almost two months since my first lecture.
Auteurs: Sharad Sinha;
Apparue dans: IEEE Potentials
Date publication: 05.-2017, volume: 36, issue:3, pages: 30 - 32
Editeur: IEEE
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» My L-3 Internship: The Power of Positivity
Résumé:
Ever since I was a little girl, I've known that my sole purpose was to accomplish one very simple goal: to enjoy life and be happy. So far, I've found happiness with a lot of different things; whether it be from dance, music, or going on adventures. But what trumps all of these activities is my mission: I want to live a life where I'll know that I have made a positive impact on the lives of other people. I am currently at the point in my life where I need to make some clear choices for what I would like to pursue with my career. I knew that one of the best ways for me to find some direction would be to gain as much hands-on experience as I could through projects and internships.
Auteurs: Hamna Kahn;
Apparue dans: IEEE Potentials
Date publication: 05.-2017, volume: 36, issue:3, pages: 36 - 37
Editeur: IEEE
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» Nanocrystalline CopperNickelZinc Ferrite: Efficient Sensing Materials for Ethanol and Acetone at Room Temperature
Résumé:
Nanostructured CuNiZnFe2O4 in varied molar concentrations is synthesized by the rate-controlled co-precipitation method. The powder X-ray diffraction pattern and the analysis of their micrographs have confirmed the Single-phase structure of the prepared samples. Field emission scanning electron microscopy study reveals the surface morphology of the samples with nanosized grains and open pores. The average grain size of both the prepared samples is found to be 24 and 25 nm, which is obtained by the histogram analysis of high-resolution transmission electron microscopy micrographs. The dc magnetic measurements and Mössbauer spectroscopic studies together reveal that both the samples are magnetically well ordered at the room temperature with superparamagnetic relaxation due to finite size effect. The ethanol and acetone sensing characteristics of the prepared samples are studied at room temperature by conductive measurements. The maximum sensitivity of 77% is observed for 500 ppm of acetone vapor by Cu0.5Ni0.25Zn0.25Fe2O4 (CNZ1), whereas a sensitivity of 75% is observed for 500 ppm of ethanol vapor by Cu0.25Ni0.5Zn0.25Fe2O4 (CNZ2). Moreover, a quick and good response of acetone vapors by CNZ1 and ethanol vapor by CNZ2 within 10 min is also noticeable. The sensor responses are quite stable and highly reproducible.
Auteurs: Chandra Mukherjee;R. Mondal;S. Dey;S. Kumar;Jayoti Das;
Apparue dans: IEEE Sensors Journal
Date publication: 05.-2017, volume: 17, issue:9, pages: 2662 - 2669
Editeur: IEEE
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» NaPer: A TSV Noise-Aware Placer
Résumé:
Through-silicon-via (TSV)-to-TSV coupling issue can degrade the signal integrity in 3-D integrated circuit designs. This paper develops a 3-D partitioning-based force-directed placer, NaPer, to reduce the total coupling noise between TSVs and alleviate the maximum coupling noise between them. We introduce two denoise forces: TSV decoupling force and TSV density force. The TSV decoupling force is determined by the coupling noise between TSVs for separating strong coupling TSVs, and the TSV density force is determined by the TSV density for evenly distributing TSVs. The experimental results show that NaPer can effectively reduce 15.0% total TSV coupling noise and 42.7% maximum TSV coupling noise on average with only 4.5% wirelength overhead. Besides, NaPer also shows great performance in wirelength that is competitive to the state-of-the-art 3-D placer.
Auteurs: Yu-Min Lee;Kuan-Te Pan;Chun Chen;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 05.-2017, volume: 25, issue:5, pages: 1703 - 1713
Editeur: IEEE
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» Nasal Patches and Curves for Expression-Robust 3D Face Recognition
Résumé:
The potential of the nasal region for expression robust 3D face recognition is thoroughly investigated by a novel five-step algorithm. First, the nose tip location is coarsely detected and the face is segmented, aligned and the nasal region cropped. Then, a very accurate and consistent nasal landmarking algorithm detects seven keypoints on the nasal region. In the third step, a feature extraction algorithm based on the surface normals of Gabor-wavelet filtered depth maps is utilised and, then, a set of spherical patches and curves are localised over the nasal region to provide the feature descriptors. The last step applies a genetic algorithm-based feature selector to detect the most stable patches and curves over different facial expressions. The algorithm provides the highest reported nasal region-based recognition ranks on the FRGC, Bosphorus and BU-3DFE datasets. The results are comparable with, and in many cases better than, many state-of-the-art 3D face recognition algorithms, which use the whole facial domain. The proposed method does not rely on sophisticated alignment or denoising steps, is very robust when only one sample per subject is used in the gallery, and does not require a training step for the landmarking algorithm.
Auteurs: Mehryar Emambakhsh;Adrian Evans;
Apparue dans: IEEE Transactions on Pattern Analysis and Machine Intelligence
Date publication: 05.-2017, volume: 39, issue:5, pages: 995 - 1007
Editeur: IEEE
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» Near Optimal Control Based on the Tensor-Product Technique
Résumé:
This brief investigates the near optimal control problem and targets at the rigid body attitude dynamic system that are characterized by its typical nonlinearity. In order to apply the linear matrix inequality-based optimization, a second-order linear-parameter-varying model is specifically derived from the attitude system by means of the tensor-product transformation. Furthermore, an adaptive attitude tracking control law is designed to achieve both the offline optimization and online control simplification. The final control law is provided in a combined form. As a result, the dynamic response of the system mainly depends on the near optimal virtual controller and the stability can be further guaranteed by the adaptive tracking controller. Numerical simulations are conducted to verify the effectiveness of the proposed algorithms.
Auteurs: Xiangdong Liu;Xing Xin;Zhen Li;Zhen Chen;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 05.-2017, volume: 64, issue:5, pages: 560 - 564
Editeur: IEEE
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» Network Utility Maximization in Wireless Networks Over Fading Channels With Uncertain Distribution
Résumé:
In this the network utility maximization problem is investigated for wireless networks when only channel mean and variance are known. Due to the randomness of wireless channel, link outage will happen and a traffic flow’s rate will gradually decrease along its routing path. When only channel mean and variance are known, channel distribution is uncertain and it is harder to control the rate loss caused by link outage. We take into account this feature of rate loss and target at maximizing the network utility of multiple traffic flows’ rates at their destinations. An optimization problem is formulated, which is non-convex. Global optimal solution is achieved with the aid of bilevel optimization method and monotonic optimization method. Numerical results are presented to verify the effectiveness of our proposed method.
Auteurs: Song Jin;Rongfei Fan;Gongpu Wang;Xiangyuan Bu;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1107 - 1110
Editeur: IEEE
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» Network Virtualization in Spectrum Sliced Elastic Optical Path Networks
Résumé:
The recent decade has witnessed an evolution toward virtualization of everything for the IT industry. Resources, from utility resources to networking components and functions, are abstracted as logical or virtual services. Virtualization results in elastic, agile, and automated resource provision, and facilitates the resource pricing in a pay-as-you-go model. Among this wave, the optical community has made parallel efforts in virtualizing resources in optical networks including both optical node and link resources. A virtualized optical network can not only seamlessly support automated resource provision, but also supply high-bandwidth any-to-any connectivity for network virtualization. In this paper, we overview the motivations and architecture for optical-based network virtualization. Among candidate optical networking paradigms, we argue that spectrum-sliced elastic optical path (SLICE) networks can be considered as a promising substrate choice, and study the key enabling problem, namely optical virtual network embedding over SLICE networks (OVNE-SLICE). We prove the NP-completeness of the OVNE-SLICE problem, and propose two mathematical models for this problem based on a concept named path-channel. The models are evaluated in our simulation, and compared with alternative models proposed in the literature.
Auteurs: Yang Wang;Zachary McNulty;Hung Nguyen;
Apparue dans: Journal of Lightwave Technology
Date publication: 05.-2017, volume: 35, issue:10, pages: 1962 - 1970
Editeur: IEEE
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» Network-Based Data-Driven Filtering With Bounded Noises and Packet Dropouts
Résumé:
This paper is concerned with the problem of a network-based data-driven filter design for discrete-time linear systems with bounded noises and packet dropouts. One favorable feature is that the designed filter can be directly employed without identifying the unknown system model. To compensate the negative effects of packet dropouts, an output predictor is first designed to reconstruct the missing data based on the received outputs and the inputs of the system. The asymptotic convergence of the output prediction error is established, of which the rate can be adjusted by the parameter. Then utilizing the predicted outputs and the received measurements, an almost-optimal data-driven filter with tractability is proposed within the set membership (SM) framework and the bound on the worst case estimation error is derived. Finally, two illustrative examples, including a comparison example and an application example, are presented to show the advantages of the proposed design and the effectiveness of the theoretical results.
Auteurs: Yuanqing Xia;Li Dai;Wen Xie;Yulong Gao;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 4257 - 4265
Editeur: IEEE
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» Networked Control Under Random and Malicious Packet Losses
Résumé:
We study cyber security issues in networked control of a linear dynamical system. Specifically, the dynamical system and the controller are assumed to be connected through a communication channel that face malicious attacks as well as random packet losses due to unreliability of transmissions. We provide a probabilistic characterization for the link failures which allows us to study combined effects of malicious and random packet losses. We first investigate almost sure stabilization under an event-triggered control law, where we utilize Lyapunov-like functions to characterize the triggering times at which the plant and the controller attempt to exchange state and control data over the network. We then provide a look at the networked control problem from the attacker's perspective and explore malicious attacks that cause instability. Finally, we demonstrate the efficacy of our results with numerical examples.
Auteurs: Ahmet Cetinkaya;Hideaki Ishii;Tomohisa Hayakawa;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 05.-2017, volume: 62, issue:5, pages: 2434 - 2449
Editeur: IEEE
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» Networks on Chips: 15 Years Later
Résumé:
The authors of a Computer article from 2002 reflect on their proposal to use networks on chips to address scalable communications on silicon VLSI chips.
Auteurs: Giovanni De Micheli;Luca Benini;
Apparue dans: Computer
Date publication: 05.-2017, volume: 50, issue:5, pages: 10 - 11
Editeur: IEEE
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» Neuro-Adaptive Fault-Tolerant Tracking Control of Lagrange Systems Pursuing Targets With Unknown Trajectory
Résumé:
In this paper, we address the problem of steering Lagrange system to track targets with unknown trajectory in the presence of modeling uncertainties and actuation faults. Artificial neural network technique is employed to reconstruct the behavior of the targets with unknown trajectory, with which robust adaptive fault-tolerant tracking control algorithms are developed. The developed control scheme is able to cope with unknown desired trajectory, attenuate modeling uncertainties and accommodate actuation faults. The proposed control scheme is shown to be able to maintain close target tracking despite actuation ineffectiveness and desired trajectory uncertainty. The benefits and feasibility of the developed control are also confirmed by simulations.
Auteurs: Yongduan Song;Junxia Guo;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3913 - 3920
Editeur: IEEE
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» New Active Capacitor Voltage Balancing Method for Flying Capacitor Multicell Converter Based on Logic-Form-Equations
Résumé:
This paper presents a new active capacitor voltage balancing control method for the flying capacitor multicell (FCM) converters which is fully implemented using logic-form equations. The proposed active capacitor voltage balancing control technique, measures output current and flying capacitor (FC) voltages to generate the switching states in order to produce the required output voltage level and to balance FCs’ voltages at their reference values. Output voltage of the FCM converter controlled with proposed active capacitor voltage balancing method can be modulated with any pulse width modulation (PWM) technique such as the phase-shifted-carrier PWM or level-shifted-carrier PWM. An advantage of the proposed active capacitor voltage balancing control method is its simplicity as it does not require any complex computations and tedious optimization calculations. Simulation results and experimental measurements of a three-cell four-level and four-cell five-level FCM converters are presented to verify the performance of the proposed active capacitor voltage balancing control technique.
Auteurs: Arash Khoshkbar Sadigh;Vahid Dargahi;Keith A. Corzine;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3467 - 3478
Editeur: IEEE
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» New and Optimized Magnetization Scheme for the Baby Magnetized Iron Neutrino Detector at J-PARC
Résumé:
The Baby-MIND (magnetized iron neutrino detector) collaboration is building a muon detector to be installed downstream of the WAGASCI experiment at J-PARC (Japan). Due to the challenging timeline and space constraints for the installation in the ND280 pit, an innovative magnetization scheme has been developed for the iron plates. The magnetization scheme optimizes flux return for minimum stray field and operating current, while maximizing the useful tracking area with $B > 1.5$ T. The 33 iron plates of the detector are individually magnetized by coils wound on their surface by “sewing” an aluminum conductor through slits cut in the plates. In this paper, we present the details of the magnetization scheme and coil winding procedure as well as the results of magnetization tests performed on a prototype module and the first eighteen detector plates.
Auteurs: Gabriella Rolando;Philippe Benoit;Alain Blondel;Alexey Dudarev;Etam Noah;Helder Pais Da Silva;Mark Rayner;Herman H. J. ten Kate;
Apparue dans: IEEE Transactions on Magnetics
Date publication: 05.-2017, volume: 53, issue:5, pages: 1 - 6
Editeur: IEEE
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» New Beamforming Designs for Joint Spatial Division and Multiplexing in Large-Scale MISO Multi-User Systems
Résumé:
In this paper, we study a joint spatial division multiplexing (JSDM) beamforming scheme, which enables large-scale spatial multiplexing gains for massive multi-input multi-output downlink systems. In contrast to the conventional JSDM, which employs a block diagonalization method as a pre-beamformer, we aim to maximize sum-rate by applying minimum-mean-squared error (MMSE) approaches when designing a pre-beamformer and a multi-user precoder sequentially. First, to suppress inter-group interference, we design the pre-beamformer, which minimizes an upper bound of the sum mean-squared-error in the large-scale array regime. Then, to mitigate same-group interference, we present the multi-user precoder based on the weighted MMSE (WMMSE) optimization method, which requires the same channel state information overhead as the conventional JSDM. Also, in order to reduce the computational complexity, we compute deterministic equivalents of the WMMSE beamforming parameters to generate the beamformers by employing asymptotic results of large system analysis. Through simulation results, we confirm that the proposed two-step beamforming methods bring substantial performance gains in terms of sum-rate over the conventional JSDM schemes especially in a low and medium signal-to-noise ratio regime with comparable complexity.
Auteurs: Younghyun Jeon;Changick Song;Sang-Rim Lee;Seungjoo Maeng;Jaehoon Jung;Inkyu Lee;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 05.-2017, volume: 16, issue:5, pages: 3029 - 3041
Editeur: IEEE
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» New Design of a Variable Impedance Based on Polarized Diodes at Microwave Frequency
Résumé:
In this letter, we present a new variable impedance termination consisting of two polarized diodes. To generate a complex-valued impedance, two controlled current sources polarize the diodes, which are interconnected with a Wilkinson power divider through transmission lines of different electric lengths. Because of the reduced number of diodes, this structure presents low power consumption and simple control. We validated the proposed design by implementing a prototype at the operating frequency of 1575.42 MHz. Mapping the measured results in the Smith chart, the impedance can produce reflection coefficients with full-phase coverage within the circle of magnitude 0.35 over a frequency range of 1.5–1.6 GHz.
Auteurs: Alejandro J. Venere;Martín Hurtado;Ramón Lopéz La Valle;Carlos H. Muravchik;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 05.-2017, volume: 27, issue:5, pages: 470 - 472
Editeur: IEEE
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» New Directions in Navigation and Positioning: Signal processing-enabled technologies pinpoint people, places, and things [Special Reports]
Résumé:
In an era of same-day product deliveries, interplanetary space probes, and autonomous vehicles, transporting something—or someone—from here to there quickly, directly, and precisely is becoming increasingly important. An array of navigation and positioning technologies are now available to help guide and locate vehicles, people, and almost endless number of objects. The satellite-based global positioning system (GPS), for instance, now lies at the heart of an almost endless array of location, navigation, timing, mapping, and tracking tools. Real-time location system (RTLS) technologies, meanwhile, rely on resources such as GPS, Wi-Fi, Bluetooth, near-field communication (NFC), and radio-frequency identification (RFID) to detect the current location of a target, which may be anything from a vehicle to an item in a manufacturing plant to a person.
Auteurs: John Edwards;
Apparue dans: IEEE Signal Processing Magazine
Date publication: 05.-2017, volume: 34, issue:3, pages: 10 - 13
Editeur: IEEE
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» New for IMS2017: Exhibitor Workshops
Résumé:
Provides a notice of upcoming conference events of interest to practitioners and researchers.
Auteurs: Bryan Wu;Susie Horn;Lee Wood;
Apparue dans: IEEE Microwave Magazine
Date publication: 05.-2017, volume: 18, issue:3, pages: 68 - 76
Editeur: IEEE
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» Newly Elected CIS Administrative Committee Members (2017-2019) [Society Briefs]
Résumé:
Presents a listing of newly elected CIS administrative committee members.
Auteurs: Pablo A. Estevez;
Apparue dans: IEEE Computational Intelligence Magazine
Date publication: 05.-2017, volume: 12, issue:2, pages: 11 - 12
Editeur: IEEE
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» NLMS Algorithm Based on a Variable Parameter Cost Function Robust Against Impulsive Interferences
Résumé:
The conventional step-size scaler (SSS) normalized least-mean-square algorithm is robust against impulsive noise. However, the constant parameter in the SSS needs to be controlled to satisfy the conflicting requirements of fast convergence rate and low steady-state misadjustment. Therefore, to address this problem, an adaptive approach for the parameter in the cost function is proposed in this brief. The proposed approach is then tested in system identification and acoustic echo-cancelation scenarios, which have demonstrated that the proposed approach is effective and robust against non-Gaussian impulsive interferences.
Auteurs: Fuyi Huang;Jiashu Zhang;Sheng Zhang;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 05.-2017, volume: 64, issue:5, pages: 600 - 604
Editeur: IEEE
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» No Downlink Pilots Are Needed in TDD Massive MIMO
Résumé:
We consider the Massive Multiple-Input Multiple-Output downlink with maximum-ratio and zero-forcing processing and time-division duplex operation. To decode, the users must know their instantaneous effective channel gain. Conventionally, it is assumed that by virtue of channel hardening, this instantaneous gain is close to its average and hence that users can rely on knowledge of that average (also known as statistical channel information). However, in some propagation environments, such as keyhole channels, channel hardening does not hold. We propose a blind algorithm to estimate the effective channel gain at each user, that does not require any downlink pilots. We derive a capacity lower bound of each user for our proposed scheme, applicable to any propagation channel. Compared with the case of no downlink pilots (relying on channel hardening), and compared with training-based estimation using downlink pilots, our blind algorithm performs significantly better. The difference is especially pronounced in environments that do not offer channel hardening.
Auteurs: Hien Quoc Ngo;Erik G. Larsson;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 05.-2017, volume: 16, issue:5, pages: 2921 - 2935
Editeur: IEEE
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» No-Reference and Robust Image Sharpness Evaluation Based on Multiscale Spatial and Spectral Features
Résumé:
The human visual system exhibits multiscale characteristic when perceiving visual scenes. The hierarchical structures of an image are contained in its scale space representation, in which the image can be portrayed by a series of increasingly smoothed images. Inspired by this, this paper presents a no-reference and robust image sharpness evaluation (RISE) method by learning multiscale features extracted in both the spatial and spectral domains. For an image, the scale space is first built. Then sharpness-aware features are extracted in gradient domain and singular value decomposition domain, respectively. In order to take into account the impact of viewing distance on image quality, the input image is also down-sampled by several times, and the DCT-domain entropies are calculated as quality features. Finally, all features are utilized to learn a support vector regression model for sharpness prediction. Extensive experiments are conducted on four synthetically and two real blurred image databases. The experimental results demonstrate that the proposed RISE metric is superior to the relevant state-of-the-art methods for evaluating both synthetic and real blurring. Furthermore, the proposed metric is robust, which means that it has very good generalization ability.
Auteurs: Leida Li;Wenhan Xia;Weisi Lin;Yuming Fang;Shiqi Wang;
Apparue dans: IEEE Transactions on Multimedia
Date publication: 05.-2017, volume: 19, issue:5, pages: 1030 - 1040
Editeur: IEEE
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» Non-Invasive Stimulation-Based Tactile Sensation for Upper-Extremity Prosthesis: A Review
Résumé:
An ideal hand prosthesis should provide satisfying functionality based on reliable decoding of the user’s intentions and deliver tactile feedback in a natural manner. The absence of tactile feedback impedes the functionality and efficiency of dexterous hand prostheses, which leads to a high rejection rate from prostheses users. Thus, it is expected that integration of tactile feedback with hand prostheses will improve the manipulation performance and enhance perceptual embodiment for users. This paper reviews the state-of-the-art of non-invasive stimulation-based tactile sensation for upper-extremity prostheses, from the physiology of the human skin, to tactile sensing techniques, non-invasive tactile stimulation, and an emphasis on electrotactile feedback. The paper concludes with a detailed discussion of recent applications, challenging issues, and future developments.
Auteurs: Kairu Li;Yinfeng Fang;Yu Zhou;Honghai Liu;
Apparue dans: IEEE Sensors Journal
Date publication: 05.-2017, volume: 17, issue:9, pages: 2625 - 2635
Editeur: IEEE
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» Non-Iterative Enhanced SDP Relaxations for Optimal Scheduling of Distributed Energy Storage in Distribution Systems
Résumé:
Convexification of an optimal scheduling algorithm for distributed energy storage (DES) in radial distribution systems with high penetration of photovoltaic resources is studied. The AC power flow equalities are taken into account as constraints in the optimization model. Different from the typical optimal power flow problem, the objective function of a DES optimal scheduling (DESOS) problem varies with changing operational requirements. In this paper, three frequently-used objective functions are considered for the DESOS problem. Two of them are monotonic over the feasible set while the third is not. An illustrative example elucidates that the descent direction of a chosen objective function significantly impacts the efficiency of the second-order cone programming (SOCP) relaxation for the DESOS problem. To obtain tighter semidefinite programming (SDP) relaxations for the DESOS cases where the SOCP relaxation is not exact, this paper looks for computationally efficient convex constraints that can approximate the rank-1 constraint in the non-iterative framework. The designed non-iterative enhanced SDP relaxations are compared in terms of tightness of convexification for the DESOS problems considering the three objective functions independently. The comparison is performed on several radial IEEE test systems and a real world distribution feeder.
Auteurs: Qifeng Li;Vijay Vittal;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 1721 - 1732
Editeur: IEEE
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» Nonintrusive Power Measurement Method With Phase Detection for Low-Cost Smart Meters
Résumé:
This paper describes a nonintrusive power measurement method that is suitable for a new type of low-cost and easy-to-install smart meters in measuring current and power from parallel electric cables based on noncontact magnetic flux and identifying the power consumption of each phase. By placing noncontact magnetic flux sensors close to the parallel electric cables that carry electric currents, a method for providing flux-to-current conversion and reducing mutual coupling effects among these cables is introduced. By using the mains voltage of the electronic control circuit as a reference, a new and simple method for accurately differentiating the phase currents and power in the cables is proposed. The proposed method has been verified with practical power measurements with reasonable accuracy for this specific application.
Auteurs: Haoyuan Yang;Shu-Yuen Ron Hui;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3962 - 3969
Editeur: IEEE
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» Noninvasive Brain Stimulation Using Strong-Coupling Effect of Resonant Magnetics
Résumé:
This paper presents a novel noninvasive electromagnetic brain stimulation system, namely the transcranial magnetic stimulation (TMS), via strongly coupled magnetic resonances, which is used to improve treatment effects, enrich treatment means, and increase energy utilizations. To achieve expected stimulation effects, the conventional TMS system normally needs strict requirements for the power supply and the circuit. Inevitably, it not only deteriorates the implementability and flexibility of the noninvasive electromagnetic brain stimulation, but also increases the manufacture cost and energy consumption, thus significantly impeding the popularization of TMS technologies. Hence, a novel TMS system is proposed by utilizing the magnetic resonant coupling (MRC) mechanism, aiming to offer a brand new way to fulfill expected stimulation effects. By comparing with conventional TMS systems, the proposed system can effectively increase the strength so as to improve the stimulation depth, enhance the focality so as to prevent from impacting on nonfocal zones, and reduce the requirement on the power and frequency so as to promote the popularization of noninvasive electromagnetic treatments. In this paper, both simulation and experimental results are provided to verify the feasibility and superiority of the proposed MRC-based TMS system.
Auteurs: Bin Deng;Shuai Li;Bin Li;Jiang Wang;Zhen Zhang;
Apparue dans: IEEE Transactions on Magnetics
Date publication: 05.-2017, volume: 53, issue:5, pages: 1 - 9
Editeur: IEEE
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» Nonlinear Radar for Finding RF Electronics: System Design and Recent Advancements
Résumé:
An extensive review of nonlinear radar systems is performed. Emphasis is placed on designs relevant to detecting RF electronics that were not intentionally manufactured as visible radar targets. The state of the art in nonlinear radar is conveyed by presenting high-level system architecture, explaining the rationale behind design decisions pertaining to that architecture, and listing the specifications that nonlinear radar designers have achieved. The authors’ recent advancements in nonlinear radar technology are summarized.
Auteurs: Gregory J. Mazzaro;Anthony F. Martone;Kenneth I. Ranney;Ram M. Narayanan;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 05.-2017, volume: 65, issue:5, pages: 1716 - 1726
Editeur: IEEE
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» Nonvolatile Resistance Effect Modulated by Pulse With Laser Observed in Nano-Carbon Film
Résumé:
A nonvolatile resistance effect modulated by pulse with laser was observed in nano-carbon oxide semiconductor structures. By applying a short voltage pulse with laser illumination, the lateral resistance of the structure can be permanently changed. The resistance change ratio can reach up to 65%. More interestingly, the effect shows polarity under different illumination spot and voltage directions. This phenomenon is attributed to the trapping effect of laser-stimulated electrons in be useful for the development of laser-and pulse-modulated resistors, switches, and sensors.
Auteurs: Z. K. Gan;P. Q. Zhou;X. Huang;C. L. Mei;J. Q. Hu;H. Wang;
Apparue dans: IEEE Electron Device Letters
Date publication: 05.-2017, volume: 38, issue:5, pages: 560 - 563
Editeur: IEEE
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» Not Happy? Move On
Résumé:
Over the past 50 years, a number of papers have been published in an attempt to determine what factors make an employee happy and satisfied versus those factors that lead to dissatisfaction and poor performance. Perhaps the two most prominent authors are Frederick Hertzberg and Abraham Maslow. While Maslow first published his hierarchy of needs, Herzberg extended that work, developing his own needs model. The two models compare quite closely, with minor differences in the words used to define the separate levels of an individual's feeling of satisfaction on the job.
Auteurs: Raymond E. Floyd;
Apparue dans: IEEE Potentials
Date publication: 05.-2017, volume: 36, issue:3, pages: 23 - 25
Editeur: IEEE
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» Novel Chest Compression Depth Measurement Sensor Using IR-UWB for Improving Quality of Cardiopulmonary Resuscitation
Résumé:
Cardiac arrest is a common cause of death in the world. Immediate high-quality cardiopulmonary resuscitation (CPR) improves the chances of survival of cardiac arrest patients. In particular, maintaining an adequate chest compression depth (CCD) during CPR is a key determinant for survival from cardiac arrest. If it is possible to measure the CCD accurately during CPR, we could increase the survival rate of patients by improving the quality of CPR. This work proposes a new sensor that could measure the CCD accurately during CPR. Compared with existing sensors that utilize pressures or accelerometers, the proposed sensor employs distance measurements based on the time-difference-of-arrival using impulse-radio ultra-wideband (IR-UWB). The method directly measures the CCD using two antennas at the chest and at the back, thereby eliminating the distance error under CPR environments, which is present in existing accelerometer sensors. The designed sensor has an 0.08 mm resolution, and an inaccuracy of less than ±1.25 mm, within a range of 0-40 cm. This sensor was applied to a CPR manikin to measure the CCD in an environment where CPR is performed.
Auteurs: Yeomyung Kim;Byung Gyu Yu;Je Hyeok Oh;Tae Wook Kim;
Apparue dans: IEEE Sensors Journal
Date publication: 05.-2017, volume: 17, issue:10, pages: 3174 - 3183
Editeur: IEEE
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» Novel Dynamic Voltage Support Capability of Photovoltaic Systems for Improvement of Short-Term Voltage Stability in Power Systems
Résumé:
The large integration of photovoltaic (PV) power generation systems into power systems causes deterioration in power system stability. In our previous work, we showed that reactive power control using the inverters of PV systems, known as dynamic voltage support (DVS) capability, is a promising approach to improve the short-term voltage stability in power systems. In this paper, we propose a novel DVS capability as a function of PV inverters. In contrast to the conventional DVS capability, the proposed method uses both active and reactive power injection to improve the short-term voltage stability. Numerical examples show that the proposed DVS capability further improves the short-term voltage stability compared with the conventional DVS capability. Furthermore, the proposed method can alleviate a frequency drop after a fault caused by interruption in PV systems.
Auteurs: Kenichi Kawabe;Yutaka Ota;Akihiko Yokoyama;Kazuyuki Tanaka;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 1796 - 1804
Editeur: IEEE
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» Novel Fast Coherent Detection Algorithm for Radar Maneuvering Target With Jerk Motion
Résumé:
The detection performance of radar maneuvering target with jerk motion is affected by the range migration (RM) and Doppler frequency migration (DFM). To address these problems, a fast algorithm without searching target's motion parameters is proposed. In this algorithm, the second-order keystone transform is first applied to eliminate the quadratic coupling between the range frequency and slow time. Then, by employing a new defined symmetric autocorrelation function, scaled Fourier transform, and inverse fast Fourier transform, the target's initial range and velocity are estimated. With these two estimates, the azimuth echoes along the target's trajectory, which can be modeled as a cubic phase signal (CPS), are extracted. Thereafter, the target's radial acceleration and jerk are estimated by approaches for parameters estimation of the CPS. Finally, by constructing a compensation function, the RM and DFM are compensated simultaneously, followed by the coherent integration and target detection. Comparisons with other representative algorithms in computational cost, motion parameter estimation performance, and detection ability indicate that the proposed algorithm can achieve a good balance between the computational cost and detection ability. The simulation and raw data processing results demonstrate the effectiveness of the proposed algorithm.
Auteurs: Jiancheng Zhang;Tao Su;Jibin Zheng;Xuehui He;
Apparue dans: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Date publication: 05.-2017, volume: 10, issue:5, pages: 1792 - 1803
Editeur: IEEE
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» Novel Folded-KES Architecture for High-Speed and Area-Efficient BCH Decoders
Résumé:
In this brief, we present a novel folding technique for high-speed and low-cost Bose–Chaudhuri–Hocquenghem (BCH) decoders. In the conventional BCH decoder, the critical path lies on the Galois-field (GF) multiplier of the key equation solver, where the speedup of the critical path is very difficult due to a significant area increase. In the proposed work, the regularly structured GF multiplier is introduced to be efficiently folded to reduce the complexity and the critical delay. Moreover, the conventional global folding scheme can be applied to further reduce the hardware costs. The implementation results show that the proposed folding scheme enhances the area efficiency by 1.73 and 1.9 times in the Digital Video Broadcasting–Satellite–Second Generation system and the storage controller, respectively.
Auteurs: Byeonggil Park;Seungyong An;Jongsun Park;Youngjoo Lee;
Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs
Date publication: 05.-2017, volume: 64, issue:5, pages: 535 - 539
Editeur: IEEE
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» Novel Matching Network and Its Application to Quad-Channel Diplexers
Résumé:
This letter reports a new kind of matching network for quad-channel diplexers. The matching network is comprised by some open- and short-circuited transmission lines, which can be chosen based on the design graph. The impact of loading resonators on the network is discussed. The diplexer can be easily realized by the combination of different bandpass filters without complicated tuning. To illustrate the concept, one quad-channel diplexer is designed, fabricated, and measured. Simulated and measured results are found to be in good agreement with each other.
Auteurs: Qiang Shao;Fu-Chang Chen;Jian-Feng Qian;Jie-Ming Qiu;Qing-Xin Chu;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 05.-2017, volume: 27, issue:5, pages: 452 - 454
Editeur: IEEE
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» Novel Methodology for Selecting Representative Operating Points for the TNEP
Résumé:
As part of transmission network expansion planning (TNEP), a technical and economical assessment of several planning alternatives must be performed in order to ensure fulfillment of the network security criteria and to estimate the alternatives’ expected operating costs. This task requires performing load flow calculations for different operating points (OPs) of the power system. Due to the high computational burden, considering all possible OPs is simply not possible. As a consequence, only a set of representative OPs is usually taken into account. Most works in the TNEP focus on issues related to optimization algorithms and modeling, neglecting the selection process of the representative OPs. Furthermore, most works only consider a few OPs, providing little or no insight about the criteria used in the selection process or about the error made when evaluating planning alternatives using a limited number of OPs. In this work, a novel methodology for selecting representative OPs to consider within the TNEP is presented. The proposal pays special attention to critical situations, where the network security may be endangered. Furthermore, the methodology allows quantifying the error made when evaluating network operation using a limited number of representative OPs.
Auteurs: Ricardo Alvarez;Albert Moser;Claudia Andrea Rahmann;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 2234 - 2242
Editeur: IEEE
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» Novel Microfluidically Tunable Differential Dual-Mode Patch Filter
Résumé:
This letter presents a novel microfluidcally tunable differential bandpass filter (BPF) with precisely controlled passband frequency. The frequency tunability of the filter is realized by inserting microfluidic channels, which can be filled with high dielectric constant fluid, i.e., distilled water, between the dual-mode patch resonator and the ground plane. Meanwhile, the frequency-tuning capability of the channels highly depends on the E-field distributions of the two modes on the patch. By properly choosing the orientations and spaces of the channels, the two-mode resonant frequencies can be simultaneously shifted up/down, and thus the frequency tuning states of the differential-mode passband can be precisely controlled with proper water-filling sequence. For demonstration, the proposed BPF is designed and fabricated. The simulated and measured results are presented, showing good agreement.
Auteurs: Wen-Jun Zhou;Hui Tang;Jian-Xin Chen;
Apparue dans: IEEE Microwave and Wireless Components Letters
Date publication: 05.-2017, volume: 27, issue:5, pages: 461 - 463
Editeur: IEEE
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» Novel Multidimensional Models of Opinion Dynamics in Social Networks
Résumé:
Unlike many complex networks studied in the literature, social networks rarely exhibit unanimous behavior, or consensus. This requires a development of mathematical models that are sufficiently simple to be examined and capture, at the same time, the complex behavior of real social groups, where opinions and actions related to them may form clusters of different size. One such model, proposed by Friedkin and Johnsen, extends the idea of conventional consensus algorithm (also referred to as the iterative opinion pooling) to take into account the actors’ prejudices, caused by some exogenous factors and leading to disagreement in the final opinions. In this paper, we offer a novel multidimensional extension, describing the evolution of the agents’ opinions on several topics. Unlike the existing models, these topics are interdependent, and hence the opinions being formed on these topics are also mutually dependent. We rigorously examine stability properties of the proposed model, in particular, convergence of the agents’ opinions. Although our model assumes synchronous communication among the agents, we show that the same final opinions may be reached “on average” via asynchronous gossip-based protocols.
Auteurs: Sergey E. Parsegov;Anton V. Proskurnikov;Roberto Tempo;Noah E. Friedkin;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 05.-2017, volume: 62, issue:5, pages: 2270 - 2285
Editeur: IEEE
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» Novel Radiation-Hardened-by-Design (RHBD) 12T Memory Cell for Aerospace Applications in Nanoscale CMOS Technology
Résumé:
In this paper, a novel radiation-hardened-by-design (RHBD) 12T memory cell is proposed to tolerate single node upset and multiple-node upset based on upset physical mechanism behind soft errors together with reasonable layout-topology. The verification results obtained confirm that the proposed 12T cell can provide a good radiation robustness. Compared with 13T cell, the increased area, power, read/write access time overheads of the proposed 12T cell are −18.9%, −23.8%, and 171.6%/−50.0%, respectively. Moreover, its hold static noise margin is 986.2 mV which is higher than that of 13T cell. This means that the proposed 12T cell also has higher stability when it provides fault tolerance capability.
Auteurs: Jing Guo;Lei Zhu;Wenyi Liu;Hai Huang;Shanshan Liu;Tianqi Wang;Liyi Xiao;Zhigang Mao;
Apparue dans: IEEE Transactions on Very Large Scale Integration Systems
Date publication: 05.-2017, volume: 25, issue:5, pages: 1593 - 1600
Editeur: IEEE
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» Novel Summation Inequalities and Their Applications to Stability Analysis for Systems With Time-Varying Delay
Résumé:
The inequality technique plays an important role in stability analysis for time-delay systems. This technical note presents a new sequence of novel summation inequalities by introducing some free matrices, which includes the newly-developed Wirtinger-based and free-matrix-based summation inequalities as special cases. Moreover, the idea can be easily extended to the multiple-summation-inequality case. Based on the proposed inequalities, relaxed stability conditions are obtained for systems with time-varying delay. Numerical examples are given to demonstrate the effectiveness of the proposed approach.
Auteurs: Jun Chen;Shengyuan Xu;Xianglei Jia;Baoyong Zhang;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 05.-2017, volume: 62, issue:5, pages: 2470 - 2475
Editeur: IEEE
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» Novel Two-Phase Approach for Process Optimization of Customer Collaborative Design Based on Fuzzy-QFD and DSM
Résumé:
In response to fast-growing and rapidly changing global markets, launching new products faster than competitors does not only assist enterprises in acquiring a larger market share, but also in reducing development lead time. However, owing to the intrinsically uncertain properties of new product development management, manufacturing companies often struggle with the dilemma of whether to increase product variety or control manufacturing complexity. This paper proposes a novel two-phase method to assist an enterprise in achieving a customer collaborative product design. In the first phase, quality function deployment, which is based on fuzzy multicriteria decision making and suppliers’ budget constraints, is presented to maximize customers’ satisfaction. In the second phase, an effective approach is proposed to determine the appropriate sequence of several coupled activities with the minimum total feedback time in a design structure matrix. Finally, a real case is used to illustrate the overall applicability of the approach. The optimization results show the effectiveness and superiority of the proposed method over other reported methods in the literature.
Auteurs: Aijun Liu;Hesuan Hu;Xiao Zhang;Deming Lei;
Apparue dans: IEEE Transactions on Engineering Management
Date publication: 05.-2017, volume: 64, issue:2, pages: 193 - 207
Editeur: IEEE
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» Numerical Investigation of an UWB Localization Technique for Unmanned Aerial Vehicles in Outdoor Scenarios
Résumé:
In this paper, the numerical investigation of an ultra wideband (UWB) localization technique suitable for the tracking and control of an unmanned aerial vehicle (UAV) in a specific outdoor scenario is presented. A set of UWB nodes are located on a moving/still ground station (GS) and interrogate an UWB node placed on the UAV that is flying in front of the GS. The distances between the GS-nodes and the UAV-node are estimated through a conventional two-way time-of-flight ranging method, one at a time, and then used in a multilateration algorithm. Due to the unavoidable relative motion between the UAV and the GS, the above distances are actually measured for different UAV-GS relative positions, and then, the UAV localization performance deteriorates as a function of the UAV-GS relative speed and the ranging-method processing time. An approach is here proposed to mitigate the above adverse effect, by exploiting an estimate of the UAV-GS relative speed along the GS forward direction. A preliminary numerical analysis is used to show that a decimeter order localization accuracy can be obtained for a tridimensional localization process.
Auteurs: Fabrizio Lazzari;Alice Buffi;Paolo Nepa;Sandro Lazzari;
Apparue dans: IEEE Sensors Journal
Date publication: 05.-2017, volume: 17, issue:9, pages: 2896 - 2903
Editeur: IEEE
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» Numerical Manipulation of Digital Holograms for 3-D Imaging and Display: An Overview
Résumé:
In the last two decades, thanks to the considerable technological development of solid-state sensors, digital holography (DH) has gained credits as the elective imaging technique for applications in various research fields, e.g., material science, biotechnology, as well as a diagnostic tool for applications at lab-on-a-chip scale. However, since its beginning, the intrinsic coherent nature of holography made 3-D imaging and display one of its preferred applications. Still today, several research groups around the world are working to develop novel numerical solutions in the framework of DH-based 3-D imaging and display technology. In this paper, we report an overview of the most important contributions given to this field over the last years.
Auteurs: P. Memmolo;V. Bianco;M. Paturzo;P. Ferraro;
Apparue dans: Proceedings of the IEEE
Date publication: 05.-2017, volume: 105, issue:5, pages: 892 - 905
Editeur: IEEE
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» Numerical Model of an Injection-Locked Wideband Frequency Modulator for Polar Transmitters
Résumé:
We present a numerical model of a wideband injection-locked frequency modulator used in a polar transmitter for 3G cellular radio application. At the heart of the system is a self-injection-locked oscillator with a programmable linear tuning range of up to 200 MHz at 4-GHz oscillation frequency. The oscillator is injection locked to a time-delayed version of its resonating voltage, and its frequency is modulated by manipulating the phase and amplitude of the injected current. The model is used to study the feasibility of the proposed system by analyzing the impact of various impairments in the auxiliary injection loop on the system performance. The model is written in MATLAB/SIMULINK, and the simulation output is analyzed by a vector signal analyzer in terms of 3GPP specifications. Based on the simulation results, key specifications for individual blocks in the system are determined. The key benefits of the presented modeling methodology are simplicity, efficiency, and portability.
Auteurs: Imran Bashir;Robert Bogdan Staszewski;Poras T. Balsara;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 05.-2017, volume: 65, issue:5, pages: 1914 - 1920
Editeur: IEEE
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» Numerical Simulation of Vacuum Arc Behavior Considering Action of Adjacent Phases in Vacuum Circuit Breakers
Résumé:
In the interrupting process of a three-phase vacuum interrupter, there exists a transverse magnetic field (TMF) in the interelectrode region, which is produced by adjacent phases. The deflection of the vacuum arc caused by TMF will affect the interrupting process of vacuum circuit breakers. In this paper, the vacuum arc characteristics considering the action of TMF produced by adjacent phases is simulated based on a steady 2-D asymmetrical magnetohydrodynamic model. The simulation results show that the vacuum arc will swing around and is especially obvious at the smaller current moments near current-zero during one ac half-cycle, because of the changed direction of TMF produced by adjacent phases. This kind of swing phenomena can also be observed in the electrode erosion of unsuccessful interruption. At the moments near current-zero, axial magnetic field is relatively weaker, while TMF generated by adjacent phases is relatively stronger, therefore, the offset phenomenon of plasma parameters is more significant. Compared with smaller diameter electrode arc, larger diameter electrode has larger arc deflection distance, while its value of plasma parameters is much smaller.
Auteurs: Lijun Wang;Kang Qin;Lilan Hu;Xiao Zhang;Shenli Jia;
Apparue dans: IEEE Transactions on Plasma Science
Date publication: 05.-2017, volume: 45, issue:5, pages: 859 - 867
Editeur: IEEE
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» Object-Based Analysis and Fusion of Optical and SAR Satellite Data for Dwelling Detection in Refugee Camps
Résumé:
This study investigates the potential of very high spatial resolution (VHSR) optical WorldView-2 (WV-2) and single-polarized TerraSAR-X (TSX) synthetic aperture radar (SAR) satellite data for an automated detection of different dwelling types in a refugee camp by means of object-based image analysis (OBIA). First, the optical data and SAR data are analyzed independently, and then a fusion of both data sets is performed applying two different approaches: 1) an overlay operation-based procedure integrating the independent results of the optical- and SAR-based dwelling detection, and 2) a feature-based analysis approach taking advantage of the conjoint analysis of both data sets. The results of the single-sensor and the data fusion approaches are evaluated in detail on the basis of object-based and area-based accuracy assessments. Advantages and limitations of the analysis approaches are discussed. The accuracy rates reveal that the use of optical satellite data shows promising results regardless of the dwelling material, while the SAR data are suitable for the detection of metal sheet dwellings only. In complex camp areas, with closely spaced containers, the results of the independent analyses can be improved significantly by the proposed fusion approaches. The combination of SAR and optical data allows for the separation of contiguous dwellings in cases this was not possible by the optical sensor information
Auteurs: Kristin Spröhnle;Eva-Maria Fuchs;Patrick Aravena Pelizari;
Apparue dans: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Date publication: 05.-2017, volume: 10, issue:5, pages: 1780 - 1791
Editeur: IEEE
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» Observer-Based Controllers for Max-Plus Linear Systems
Résumé:
Max-plus algebra is a suitable algebraic setting to model discrete event systems involving synchronization and delay phenomena which are often found in transportation networks, communications systems, and manufacturing systems. One way of controlling this kind of systems consists in choosing the dates of input events in order to achieve the desired performances, e.g., to obtain output events in order to respect given dates. This kind of control is optimal, according to a just-in-time criterion, if the input-event dates are delayed as much as possible while ensuring the output events to occur before a desired reference date. This paper presents the observer-based controller for max-plus linear systems where only estimations of system states are available for the controller. As in the classical sense, this is a state-feedback control problem, which is solved in two steps: first, an observer computes an estimation of the state by using the input and the output measurements, then, this estimated state is used to compute the state-feedback control action. As a main result, it is shown that the optimal solution of this observer-based control problem leads to a greater control input than the one obtained with the output feedback strategy. A high throughput screening example in drug discovery illustrates this main result by showing that the scheduling obtained from the observer-based controller is better than the scheduling obtained from the output feedback controller.
Auteurs: Laurent Hardouin;Ying Shang;Carlos Andrey Maia;Bertrand Cottenceau;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 05.-2017, volume: 62, issue:5, pages: 2153 - 2165
Editeur: IEEE
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» Observer-Based Human Knee Stiffness Estimation
Résumé:
Objective: We consider the problem of stiffness estimation for the human knee joint during motion in the sagittal plane. Methods: The new stiffness estimator uses a nonlinear reduced-order biomechanical model and a body sensor network (BSN). The developed model is based on a two-dimensional knee kinematics approach to calculate the angle-dependent lever arms and the torques of the muscle-tendon-complex. To minimize errors in the knee stiffness estimation procedure that result from model uncertainties, a nonlinear observer is developed. The observer uses the electromyogram (EMG) of involved muscles as input signals and the segmental orientation as the output signal to correct the observer-internal states. Because of dominating model nonlinearities and nonsmoothness of the corresponding nonlinear functions, an unscented Kalman filter is designed to compute and update the observer feedback (Kalman) gain matrix. Results: The observer-based stiffness estimation algorithm is subsequently evaluated in simulations and in a test bench, specifically designed to provide robotic movement support for the human knee joint. Conclusion: In silico and experimental validation underline the good performance of the knee stiffness estimation even in the cases of a knee stiffening due to antagonistic coactivation. Significance: We have shown the principle function of an observer-based approach to knee stiffness estimation that employs EMG signals and segmental orientation provided by our own IPANEMA BSN. The presented approach makes realtime, model-based estimation of knee stiffness with minimal instrumentation possible.
Auteurs: Berno J. E. Misgeld;Markus Lüken;Robert Riener;Steffen Leonhardt;
Apparue dans: IEEE Transactions on Biomedical Engineering
Date publication: 05.-2017, volume: 64, issue:5, pages: 1033 - 1044
Editeur: IEEE
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» Observing Sea/Ice Transition Using Radar Images Generated From TechDemoSat-1 Delay Doppler Maps
Résumé:
In this letter, Global Navigation Satellite System Reflectometry (GNSS-R) delay Doppler maps (DDMs) acquired by the U.K. TechDemoSat-1 (TDS-1) mission are analyzed to identify sea ice infesting waters in circumpolar areas. First, the sensitivity of actual DDM to sea ice is investigated using reference information provided by a Sentinel-1 synthetic aperture radar imagery and a Special Sensor Microwave/Imager based sea–ice concentration map. Then, a new product is proposed that consists of normalized radar cross section measurements derived from actual DDMs and arranged in gridded format. This product is shown to provide spatial information on the sea ice transition that cannot be obtained exploiting the conventional DDM product. Hence, this new product can be used to improve/complement conventional remote sensing techniques for sea ice observation.
Auteurs: Domenico Schiavulli;Frédéric Frappart;Guillaume Ramillien;José Darrozes;Ferdinando Nunziata;Maurizio Migliaccio;
Apparue dans: IEEE Geoscience and Remote Sensing Letters
Date publication: 05.-2017, volume: 14, issue:5, pages: 734 - 738
Editeur: IEEE
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» Observing the Permanent-Magnet Temperature of Synchronous Motors Based on Electrical Fundamental Wave Model Quantities
Résumé:
Estimating the magnet temperature of permanent-magnet synchronous motors on a model basis is the key for both the highest device utilization and preventing irreversible demagnetization. Using an exact flux linkage observer in the fundamental wave domain is an elegant way to indirectly retrieve the magnet temperature without requiring any additional sensors or signal injection. This contribution addresses several important issues for the real-world applicability of a permanent magnet temperature observer: thermal expansion affecting the radial air gap thickness, operation at low speeds or even standstill, and estimating the fundamental content of the motor's terminal voltage within one switching cycle. The proposed observer is comprehensively validated in the entire electrical and thermal operation range achieving a satisfying worst case error less than 10 K.
Auteurs: Oliver Wallscheid;Andreas Specht;Joachim Böcker;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3921 - 3929
Editeur: IEEE
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» Occluded Object Detection in High-Resolution Remote Sensing Images Using Partial Configuration Object Model
Résumé:
Deformable-part-based model (DPM) has shown great success in object detection in recent years. However, its performance will degrade on partially occluded objects and is even worse on largely occluded objects in real remote sensing applications. To address this problem, a novel partial configuration object model (PCM) is developed in this paper. Compared to conventional single-layer DPMs, an extra partial configuration layer, which is composed of partial configurations defined according to possible occlusion patterns, is introduced in PCM to block the transmission of occlusion impact. During detection, each hypothesis from a partial configuration layer will infer the entire object based on spatial interrelationship and final detection results are obtained from the fusion of these possible entire objects using a weighted continuous clustering method. As PCM makes a better compromise between the deformation modeling flexibility of small parts and the discriminative shape-capturing capability of large DPM, its performance on occluded object detection will be improved. Moreover, occlusion states of detected objects can be inferred with the intermediate results of our model. Experimental results on multiple high-resolution remote sensing image datasets demonstrate the effectiveness of the proposed model.
Auteurs: Shaohua Qiu;Gongjian Wen;Yaxiang Fan;
Apparue dans: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Date publication: 05.-2017, volume: 10, issue:5, pages: 1909 - 1925
Editeur: IEEE
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» OFDM Based Multi-Node Transmission in the Presence of Phase Noises for Small Cell Backhaul
Résumé:
In this letter, the phase noise (PN) effect on orthogonal frequency division multiplexing based multi-node transmission for small cell backhaul is studied. Since each transmitter is equipped with an independent oscillator, the received signals are corrupted by all of these independent PNs (plus the PN at the receiver), which renders the conventional PN compensation schemes at the receiver ineffective. In this letter, a PN compensation scheme for multi-node transmission is proposed, which can effectively mitigate the effect of the multiple PNs.
Auteurs: Xiaoming Chen;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1207 - 1210
Editeur: IEEE
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» Off-the-Grid Compressive Time Delay Estimation via Manifold-Based Optimization
Résumé:
The time delay estimation (TDE) of some known waveforms from sampled data is of great interest in the area of signal processing, e.g., wireless communication, radar, and sonar. Classical algorithms, such as matched filters, multiple signal classification always work under the Nyquist sampling rate determined by the bandwidth of the waveform. With the assumption of sparsity, the novel compressive sensing (CS)-based algorithms are proposed in recent studies, which theoretically reduce the sampling rate but preserve the same accuracy. Yet these novel algorithms often suffer from the-so-called off-the-grid issue (or basis mismatch) and do not perform as well as expectations. This letter proposes a manifold-based optimization strategy to improve the CS-based TDE algorithms in order to solve this issue and improve the estimation accuracy and the resolution. The proposed algorithm not only achieve a much higher accuracy but also works under a much lower sampling rate compared with the state-of-the-art CS-based algorithms.
Auteurs: Wei Zhang;Feng Yu;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 983 - 986
Editeur: IEEE
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» On Connectivity and Robustness in Random Intersection Graphs
Résumé:
Random intersection graphs have received much attention recently and been used in a wide range of applications ranging from key predistribution in wireless sensor networks to modeling social networks. For these graphs, each node is equipped with a set of objects in a random manner, and two nodes have an undirected edge in between if they have at least one object in common. In this paper, we investigate connectivity and robustness in a general random intersection graph model. Specifically, we establish sharp asymptotic zero-one laws for $k$-connectivity and $k$-robustness, as well as the asymptotically exact probability of $k$-connectivity, for any positive integer $k$. The $k$ -connectivity property quantifies how resilient is the connectivity of a graph against node or edge failures, while $k$-robustness measures the effectiveness of local-information-based consensus algorithms (which do not use global graph topology information) in the presence of adversarial nodes. In addition to presenting the results under the general random intersection graph model, we consider two special cases of the general model, a binomial random intersection graph and a uniform random intersection graph, which both have numerous applications as well. For these two specialized graphs, we present asymptotically exact probabilities of $k$-connectivity and asymptotic zero-one laws for $k$-robustness.
Auteurs: Jun Zhao;Osman Yağan;Virgil Gligor;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 05.-2017, volume: 62, issue:5, pages: 2121 - 2136
Editeur: IEEE
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» On Emerging Family of Elliptic Curves to Secure Internet of Things: ECC Comes of Age
Résumé:
Lightweight Elliptic Curve Cryptography (ECC) is a critical component for constructing the security system of Internet of Things (IoT). In this paper, we define an emerging family of lightweight elliptic curves to meet the requirements on some resource-constrained devices. We present the design of a scalable, regular, and highly-optimized ECC library for both MICAz and Tmote Sky nodes, which supports both widely-used key exchange and signature schemes. Our parameterized implementation of elliptic curve group arithmetic supports pseudo-Mersenne prime fields at different security levels with two optimized-specific designs: the high-speed version (HS) and the memory-efficient (ME) version. The former design achieves record times for computation of cryptographic schemes at roughly $80sim 128$ -bit security levels, while the latter implementation only requires half of the code size of the current best implementation. We also describe our efforts to evaluate the energy consumption and harden our library against some basic side-channel attacks, e.g., timing attacks and simple power analysis (SPA) attacks.
Auteurs: Zhe Liu;Xinyi Huang;Zhi Hu;Muhammad Khurram Khan;Hwajeong Seo;Lu Zhou;
Apparue dans: IEEE Transactions on Dependable and Secure Computing
Date publication: 05.-2017, volume: 14, issue:3, pages: 237 - 248
Editeur: IEEE
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» On Low Complexity ML Decoder for Quaternion Orthogonal Designs
Résumé:
Quaternion orthogonal designs (QODs) provide an efficient way of constructing orthogonal space time polarization block codes to achieve larger transmit diversity gains without substantial increase in antenna dimensions. However, their optimal decoding remains a big challenge. This letter introduces an important constraint, which has not been emphasized before, for decoupled decoding of QODs and proposes a generalized low complexity maximum-likelihood decoder for QODs based on symmetric-paired designs. The main contribution of this letter is to explore the benefits of QODs for smaller as well as higher order designs without compromising system performance. Results show that the proposed decoder yields optimal decoupled decoding with remarkably low complexity. This letter also compares the performance of quaternion coordinate interleaved orthogonal designs (QCIODs), which provide full diversity, with proposed symmetric-paired designs and shows that proposed designs significantly outperform QCIODs.
Auteurs: Erum Mushtaq;Sajid Ali;Syed Ali Hassan;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1087 - 1090
Editeur: IEEE
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» On Market-Driven Hybrid-P2P Video Streaming
Résumé:
Consistent (pause-free) quality of service is required in peer-to-peer (P2P) video streaming systems. In this paper, we aim to eliminate the problem of playback pauses in such systems via the use of positive incentives for peers to contribute high upload rates. We model our problem as a market, where the market stakeholders consist of multiple content providers, advertisement providers, and network peers; the positive incentives for peers in the market are reduced advertisement (ad) viewing durations. From a system design perspective, one of our primary goals is to compute the market equilibria that include appropriate ad viewing durations, offering sufficient incentives for network peers to continue contributing. Our simulation-based studies demonstrate that we mitigate the “playback pause” problem for peers by up to 80% as compared to existing approaches, generate sufficient utility for advertisers to be part of the market, and enable content providers to achieve their desired utility by providing sufficient incentives for all peers to stay in the system without violating ad provider agreements.
Auteurs: Sung-Han Lin;Ranjan Pal;Bo-Chun Wang;Leana Golubchik;
Apparue dans: IEEE Transactions on Multimedia
Date publication: 05.-2017, volume: 19, issue:5, pages: 984 - 998
Editeur: IEEE
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» On Missing Tag Detection in Multiple-Group Multiple-Region RFID Systems
Résumé:
We formulate and study a missing tag detection problem arising in multiple-group, multiple-region radio frequency identification (RFID) systems, where a mobile reader needs to detect whether there is any missing event for each group of tags. The problem we tackle is to devise missing tag detection protocols with minimum execution time while guaranteeing the detection reliability requirement for each group. By leveraging the technique of Bloom filter, we develop a suite of three missing tag detection protocols, each decreasing the execution time compared to its predecessor by incorporating an improved version of the Bloom filter design and parameter tuning. By sequentially analyzing the developed protocols, we gradually iron out an optimum detection protocol that works in practice.
Auteurs: Jihong Yu;Lin Chen;Rongrong Zhang;Kehao Wang;
Apparue dans: IEEE Transactions on Mobile Computing
Date publication: 05.-2017, volume: 16, issue:5, pages: 1371 - 1381
Editeur: IEEE
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» On Novel Methods for Characterizing the Arc/Contact Movement and Its Relation With the Current/Voltage in Low-Voltage Circuit Breaker
Résumé:
This paper presents a work that was aimed to develop methods along with test facilities for characterizing the arc/contact movement in low-voltage miniature circuit breaker which has a related current under 125 A, and to find its relation with the short-circuit current/voltage in the circuit. The method consists of: 1) the high-speed camera for obtaining the image of the arc or contact movement; 2) the data acquisition system that measures the current during the short-circuit break; and 3) the circuitry system that establishes the synchronization of the arc movement capturing and the current acquisition. In particular, two methods were developed for this purpose: one based on analog signal and the other based on digital signal. The experiment shows that the accuracy of the synchronization, dependent on the sampling rate of the high-speed camera, is about from tens of microseconds to hundreds of microseconds with both methods. The two methods have their own advantages and disadvantages, and they can be tailored to applications for the best performance.
Auteurs: Chunlei Li;Dong Wei;Bing Zhang;Jin Li;Wenjun Zhang;
Apparue dans: IEEE Transactions on Plasma Science
Date publication: 05.-2017, volume: 45, issue:5, pages: 882 - 888
Editeur: IEEE
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» On Optimal Infrastructure Sharing Strategies in Mobile Radio Networks
Résumé:
The rapid evolution of mobile radio network technologies poses severe technical and economical challenges to mobile network operators (MNOs); on the economical side, the continuous roll-out of technology updates is highly expensive, which may lead to the extreme, where offering advanced mobile services becomes no longer affordable for MNOs which thus, are not incentivized to innovate. Mobile infrastructure sharing among MNOs becomes then an important building block to lower the required per-MNO investment cost involved in the technology roll-out and management phases. We focus on a radio access network (RAN) sharing situation where multiple MNOs with a consolidated network infrastructure coexist in a given set of geographical areas; the MNOs have then to decide if it is profitable to upgrade their RAN technology by deploying additional small-cell base stations and whether to share the investment (and the deployed infrastructure) of the new small-cells with other operators. We address such strategic problems by giving a mathematical framework for the RAN infrastructure sharing problem which returns the “best” infrastructure sharing strategies for operators (coalitions and network configuration) when varying techno-economic parameters such as the achievable throughput in different sharing configurations and the pricing models for the service offered to the users. The proposed formulation is then leveraged to analyze the impact of the aforementioned parameters/input in a realistic mobile network environment based on LTE technology.
Auteurs: Lorela Cano;Antonio Capone;Giuliana Carello;Matteo Cesana;Mauro Passacantando;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 05.-2017, volume: 16, issue:5, pages: 3003 - 3016
Editeur: IEEE
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» On Parallelizing Single Dynamic Simulation Using HPC Techniques and APIs of Commercial Software
Résumé:
Time-domain simulations are heavily used in today's planning and operation practices to assess power system transient stability, posttransient voltage/frequency profiles as well as oscillatory behavior following severe contingencies to comply with industry standards. Because of the increased modeling complexity, it is many times slower than real time for state-of-the-art commercial software packages to complete a dynamic simulation for a large-scale model. With the growing stochastic behavior introduced by emerging technologies, power industry has seen a growing need for performing security assessment in real time. This paper presents an innovative parallel implementation framework to speed up a single dynamic simulation by leveraging the existing stability model library in commercial tools through their application programming interfaces (APIs). Several high performance computing (HPC) techniques are explored and implemented such as parallelizing the calculation of generator current injection, identifying fast linear solvers for network solution, and parallelizing data outputs when interacting with APIs in the commercial package, TSAT. The proposed method has been tested on a Western Electricity Coordinating Council (WECC) planning base case with detailed synchronous generator models and it exhibits outstanding scalable performance with sufficient accuracy.
Auteurs: Ruisheng Diao;Shuangshuang Jin;Frederic Howell;Zhenyu Huang;Lei Wang;Di Wu;Yousu Chen;
Apparue dans: IEEE Transactions on Power Systems
Date publication: 05.-2017, volume: 32, issue:3, pages: 2225 - 2233
Editeur: IEEE
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» On Stabilization of 2D Roesser Models
Résumé:
This note is devoted to the stabilization of 2D Roesser models which are discrete, continuous, or mixed continuous-discrete. A recent linear matrix inequalities (LMIs) necessary and sufficient condition for stability of such models is used to derive a quasi non conservative technique for state feedback stabilization.
Auteurs: Olivier Bachelier;Nima Yeganefar;Driss Mehdi;Wojciech Paszke;
Apparue dans: IEEE Transactions on Automatic Control
Date publication: 05.-2017, volume: 62, issue:5, pages: 2505 - 2511
Editeur: IEEE
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» On the Asymptotic Equivalence of Circulant and Toeplitz Matrices
Résumé:
Any sequence of uniformly bounded $Ntimes N$ Hermitian Toeplitz matrices ${H_{N}}$ is asymptotically equivalent to a certain sequence of $Ntimes N$ circulant matrices ${C_{N}}$ derived from the Toeplitz matrices in the sense that $left |{H_{N}- C_{N} }right |_{F} = o(sqrt {N})$ as $Nrightarrow infty $ . This implies that certain collective behaviors of the eigenvalues of each Toeplitz matrix are reflected in those of the corresponding circulant matrix and supports the utilization of the computationally efficient fast Fourier transform (instead of the Karhunen-Loève transform) in applications like coding and filtering. In this paper, we study the asymptotic performance of the individual eigenvalue estimates. We show that the asymptotic equivalence of the circulant and Toeplitz matrices implies the individual asymptotic convergence of the eigenvalues for certain types of Toeplitz matrices. We also show that these estimates asymptotically approximate the largest and smallest eigenvalues for more general classes of Toeplitz matrices.
Auteurs: Zhihui Zhu;Michael B. Wakin;
Apparue dans: IEEE Transactions on Information Theory
Date publication: 05.-2017, volume: 63, issue:5, pages: 2975 - 2992
Editeur: IEEE
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» On the Broadcast Capacity Scaling of Large Wireless Networks at Low SNR
Résumé:
This paper focuses on the problem of broadcasting information in the most efficient manner in a large 2-D ad hoc wireless network at low SNR and under line-of-sight propagation. A new communication scheme is proposed, where source nodes first broadcast their data to the entire network, despite the lack of sufficient available power. The signal’s power is then reinforced via successive back-and-forth beamforming transmissions between different groups of nodes in the network, so that all nodes are able to decode the transmitted information at the end. This scheme is shown to achieve asymptotically the broadcast capacity of the network, which is expressed in terms of the largest singular value of the matrix of fading coefficients between the nodes in the network. A detailed mathematical analysis is then presented to evaluate the asymptotic behavior of this largest singular value.
Auteurs: Serj Haddad;Olivier Lévêque;
Apparue dans: IEEE Transactions on Information Theory
Date publication: 05.-2017, volume: 63, issue:5, pages: 3242 - 3258
Editeur: IEEE
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» On the Chiroferrite Medium-Based Waveguide Dispersion Compensator
Résumé:
The letter investigates a kind of dispersion compensator composed of dual-core planar waveguide separated by isotropic dielectric medium. Both the resonantly coupled cores are comprised of anisotropic chiroferrite materials. A dielectric clad layer of silicon dioxide is combined adjacent to one of the core sections. Supermodes are generated through mode-coupling at the resonance frequency that lead to the investigation of the group velocity dispersion (GVD) feature of the structure. The chiroferrite material parameters, particularly the chiral admittance and gyrotropy of the cores, play vital roles in achieving high GVDs. A fine tuning of resonance is achieved through proper choice of the core material parameters, and the results would be useful to devise dispersion compensator for usage in communication systems.
Auteurs: N. Iqbal;P. K. Choudhury;
Apparue dans: IEEE Photonics Technology Letters
Date publication: 05.-2017, volume: 29, issue:9, pages: 715 - 718
Editeur: IEEE
Document complet vers site de l'éditeur
 
» On the Effect of Disorder on Stray Capacitance of Transformer Winding in High-Voltage Power Supplies
Résumé:
Stray capacitance of transformer winding is an important parasitic element influencing the behavior of the switching power converters, especially for high-voltage transformers. There are various methods for calculating the stray capacitance in transformers and inductors with ordered windings. However, an ordered winding is less likely with an increased number of turns and layers. In this paper, it is shown that a slight disorderliness in winding leads to a considerable difference between the value of winding stray capacitance of the former ordered winding and its slightly disordered scheme. Therefore, regular methods for calculating the stray capacitance have significant errors in a disordered winding. A generic method is proposed to calculate the stray capacitance of a winding with disordered turns. The proposed method is to apply the probabilistic tools to evaluate the possible position of winding turns and calculation of stray capacitance for all possible winding diagrams. As the number of possible winding diagrams is very large, especially in high turn windings, Kolmogorov–Smirnov theorem is used to estimate the winding stray capacitance based on the reduced number of possible winding diagrams. The energy method is used to calculate the equivalent stray capacitance of winding. Using this calculation method, the effect of disorder and some other parameters on the value of stray capacitance is investigated. The proposed method is tested and validated with the computer simulation and the experimental measurement.
Auteurs: Morteza Aghaei;Shahriyar Kaboli;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3608 - 3618
Editeur: IEEE
Document complet vers site de l'éditeur
 
» On the Feasibility of Breast Cancer Imaging Systems at Millimeter-Waves Frequencies
Résumé:
Medical imaging currently relies on several techniques, including X-rays, magnetic resonance, and echography. However, these techniques exhibit drawbacks, and alternative approaches are required. Microwave imaging has been proposed as a possible solution, especially for breast cancer imaging. However, most of these systems work with a central frequency of a few gigahertz, and this leads to a suboptimum resolution, which can jeopardize the image quality. Millimeter waves can provide superior resolutions, at the cost of a lower penetration depth within the breast tissue. In addition, a significant fraction of the power generated by a mm-wave imaging system would be reflected back from the skin. For these reasons, and also considering that mm-wave transmitters and receivers have been historically outperformed by microwave counterparts in terms of available power and sensitivity, mm-wave imaging has not been considered a possible solution. This paper contributes to demonstrate a paradigm shift toward the possible use of mm-waves for breast cancer imaging of targets a few centimeter below the skin, a useful penetration depth for several cases. All key points are addressed using analytical, full-wave, and multiphysics simulations, including the system architecture (linear and conformal), the safety aspects (power density, specific absorption rate, and temperature increase), and the use of realistic breast models derived from ex vivo measurements.
Auteurs: Simona Di Meo;Pedro Fidel Espín-López;Andrea Martellosio;Marco Pasian;Giulia Matrone;Maurizio Bozzi;Giovanni Magenes;Andrea Mazzanti;Luca Perregrini;Francesco Svelto;Paul Eugene Summers;Giuseppe Renne;Lorenzo Preda;Massimo Bellomi;
Apparue dans: IEEE Transactions on Microwave Theory and Techniques
Date publication: 05.-2017, volume: 65, issue:5, pages: 1795 - 1806
Editeur: IEEE
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» On the Fronthaul Statistical Multiplexing Gain
Résumé:
Breaking the fronthaul capacity limitations is vital to make cloud radio access network scalable and practical. One promising way is aggregating several remote radio units (RRUs) as a cluster to share a fronthaul link, so as to enjoy the statistical multiplexing gain brought by the spatial randomness of the traffic. In this letter, a tractable model is proposed to analyze the fronthaul statistical multiplexing gain. We first derive the user blocking probability caused by the limited fronthaul capacity, including its upper and lower bounds. We then obtain the limits of fronthaul statistical multiplexing gain when the cluster size approaches infinity. Analytical results reveal that the user blocking probability decreases exponentially with the average fronthaul capacity per RRU, and the exponent is proportional to the cluster size. Numerical results further show considerable fronthaul statistical multiplexing gain even at a small to medium cluster size.
Auteurs: Liumeng Wang;Sheng Zhou;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1099 - 1102
Editeur: IEEE
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» On the Incident Power on a Receiving Slender Antenna and the Optical Theorem in the Near Field
Résumé:
Incident power upon a slender scatterer or a receiving antenna is not well defined, since physical apertures of such structures have little meaning. However, an area over which the incident power is admitted can nonetheless be defined. For a definition that relies solely on the receive mode, we develop a near-field version of the optical theorem. When equated with the conventional far-field version, an equation for the admitting area appears. This equation is solved via both a full-wave simulation and a quasi-analytical way. The result is also supported by two transmit-mode assessments. It is shown that under this definition, the half-wavelength dipole can be replaced by an equivalent aperture antenna facing the direction of the incident wave.
Auteurs: Hamid Shannan;Raphael Kastner;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2421 - 2427
Editeur: IEEE
Document complet vers site de l'éditeur
 
» On the Limits of Coexisting Coverage and Capacity in Multi-RAT Heterogeneous Networks
Résumé:
This paper devises a general modeling and analyzing framework for a heterogeneous wireless network (HetNet) in which several wireless subnetworks coexist and use multiple radio access technologies (multi-RATs). The coexisting coverage and network capacity in such a multi-RAT HetNet are hardly investigated in prior works. To characterize the coexisting interactions in a multi-RAT HetNet, in this paper, we consider a HetNet consisting of $K$ tiers of access points (APs) and two different RATs, RAT- $ mathsf {L}$ and RAT- $ mathsf {U}$ , are adopted in the HetNet. RAT- $ mathsf {L}$ is adopted by the APs in the first $K-1$ tiers and APs in the $K$ th tier only use RAT- $ mathsf {U}$ . Both noncrossing-RAT and crossing-RAT user association scenarios are considered. In each scenario, the void probability and the channel access probability of the APs in each tier are first found and then the tight lower bounds and their lowest limits on the proposed coexisting coverage and network capacity are derived. We show that multi-RAT networks in general can achieve higher link coverage and capacity by using opportunistic carrier sense multiple access with collision avoidance that avoids/alleviates severe interfering between all coexisting APs. Also, crossing-RAT user association is shown to achieve much higher coexisting coverage and network capacity than noncrossing-RAT user association. Finally, numerical simulations for the LTE-U and WiFi networks coexisting in the HetNet valida- e our findings.
Auteurs: Chun-Hung Liu;Hong-Cheng Tsai;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 05.-2017, volume: 16, issue:5, pages: 3086 - 3101
Editeur: IEEE
Document complet vers site de l'éditeur
 
» On the Optimal Set of Channels to Sense in Cognitive Radio Networks
Résumé:
In the channel selection problem, a secondary user (SU) senses a subset of size $M$ out of $N$ existing channels, and then accesses up to $K$ sensed-free channels. Given $M$ , $N$ , $K$ , and some estimates on the rates of channels, and the sensing accuracy, the channel selection problem asks what set of channels SU should sense to maximize its throughput. The intuitive answer is the set of $K$ channels with the highest rewards, where the reward of a channel is defined as the expected number of bits that can be successfully transmitted on that channel. Surprisingly, the above-mentioned intuitive solution is not optimal when $M>K$ . In this letter, we study the case $M>K$ , and propose polynomial-time optimal solutions for special cases where $K=1$ or where $M$ or $N-M$ are small. We also derive an upper bound on the maximum achievable throughput, and propose a generic near-optimal heuristic algorithm.
Auteurs: Afshin Arefi;Majid Khabbazian;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1103 - 1106
Editeur: IEEE
Document complet vers site de l'éditeur
 
» On the Optimal Tone Spacing for Interference Mitigation in OFDM-IM Systems
Résumé:
Orthogonal frequency division multiplexing with index modulation (OFDM-IM) has been recently proposed as an efficient technique to improve the error performance and enhance the spectral efficiency achieved by the classical OFDM. In this letter, we minimize the presence of intercarrier and intersymbol interference, experienced by OFDM-IM systems under mobility conditions and multipath scenarios, by selecting the appropriate tone spacing between adjacent subcarriers. Finally, we prove that the optimal value of tone spacing increases the system capacity, occupying only the necessary amount of bandwidth, and provide closed-form expressions for the interference power per active subcarrier.
Auteurs: Georgia D. Ntouni;Vasileios M. Kapinas;George K. Karagiannidis;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1019 - 1022
Editeur: IEEE
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» On the Optimization Model for Multi-Hop Information Transmission and Energy Transfer in TDMA-Based Wireless Sensor Networks
Résumé:
Wireless energy transfer (WET) has been considered a promising technique for prolonging the lifetime of wireless networks. In this letter, the joint optimization problem of multi-hop information transmission and energy transfer in TDMA-based multi-hop wireless sensor networks is modeled. Moreover, a more realistic energy consumption model is proposed, which takes the energy consumption of compression, communication, and wireless energy transfer into account. A nonlinear programming problem is formulated to achieve the maximal source rate utility. Finally, through the numerical results, the impact of system parameters on rate utility is investigated, and the role of WET in improving network performance is verified.
Auteurs: Weiqiang Xu;Weiwei Cheng;Yushu Zhang;Qingjiang Shi;Xiaodong Wang;
Apparue dans: IEEE Communications Letters
Date publication: 05.-2017, volume: 21, issue:5, pages: 1095 - 1098
Editeur: IEEE
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» On the Statistics of Coherence Estimators for Textured Clutter Plus Noise
Résumé:
This letter presents a theoretical analysis of the impact of thermal noise on the statistics of the classical as well as a modified estimator for the cross-correlation coefficient between two receive channels, which follow a noisy compound clutter model. This correlation coefficient, in the synthetic aperture radar (SAR) context often called coherence, is widely used as an important quality parameter in the field of SAR interferometry, SAR change detection, and SAR ground moving target indication. Based on a novel closed-form expressions for the probability density function (pdf) for integer number of averaged samples (or looks), it is shown that, contrary to widespread belief, the clutter texture does not cancel out when the noise contribution is taken into account. It is further demonstrated that the new pdfs can be used to derive the bias and variance of the sample coherence in analytical closed form. Thereby, the impact of the texture on the estimators is analyzed.
Auteurs: Christoph H. Gierull;
Apparue dans: IEEE Geoscience and Remote Sensing Letters
Date publication: 05.-2017, volume: 14, issue:5, pages: 679 - 683
Editeur: IEEE
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» On the VLSI Energy Complexity of LDPC Decoder Circuits
Résumé:
Sequences of randomly generated bipartite configurations are analyzed; under mild conditions almost surely such configurations have minimum bisection width proportional to the number of vertices. This implies an almost sure $Omega (n^{2}/d^{2}_{mathrm {max}})$ scaling rule for the energy of directly-implemented low-density parity-check (LDPC) decoder circuits for codes of block length $n$ and maximum node degree $d_{mathrm {max}}$ . It also implies an $Omega (n^{3/2}/d_{mathrm {max}})$ lower bound for serialized LDPC decoders. It is also shown that all (as opposed to almost all) capacity-approaching, directly-implemented non-split-node LDPC decoding circuits, have energy, per iteration, that scales as $Omega left ({chi ^{2}ln ^{3} chi }right )$ , where $chi =(1-R/C)^{-1}$ is the reciprocal gap to capacity, $R$ is code rate, and $C$ is channel capacity.
Auteurs: Christopher G. Blake;Frank R. Kschischang;
Apparue dans: IEEE Transactions on Information Theory
Date publication: 05.-2017, volume: 63, issue:5, pages: 2781 - 2795
Editeur: IEEE
Document complet vers site de l'éditeur
 
» On Unified Numerical Algorithm for 3-D Scattering From Dielectric and PEC Random Rough Surfaces
Résumé:
We present a unified fast scattering algorithm for dielectric random rough surfaces that asymptotically reduces to the perfect electric conductor (PEC) case when the loss tangent grows extremely large. The Coifman wavelets are employed to implement Galerkin’s procedure in the method of moments (MoM). The Coiflets-based surface integral equations (IEs) consist of both the tangential and normal components of electromagnetic fields as unknowns. The inherited mathematical superiority, e.g., local multiresolution analysis and high regularity with Holder index 1.449 in smoothness, allows efficiently implementing both electric field IE and magnetic field IE. Due to the high-precision one-point quadrature, the Coiflets yield fast evaluations of the most off-diagonal entries, reducing the matrix fill effort from O(N2) to O(N). The orthogonality and Riesz basis of the Coiflets generate well-conditioned impedance matrix, with rapid convergence for the conjugate gradient solver. In addition, a semianalytical expression of the tapered-wave carried power is derived, which speeds up computations of the normalization factor of scattering coefficients. Numerical results demonstrate that the reduced PEC model does not suffer from ill-posed problems, namely, matrix condition numbers are kept small and solutions are stable under extremely large loss tangent, where normal components of $H$ -field and tangential $E$ -field have vanished. Compared with the previous publications and laboratory measurements, good agreement is observed.
Auteurs: Lisha Zhang;Guangwen George Pan;Jimmy A. Jones;
Apparue dans: IEEE Transactions on Antennas and Propagation
Date publication: 05.-2017, volume: 65, issue:5, pages: 2615 - 2623
Editeur: IEEE
Document complet vers site de l'éditeur
 
» On-Chip Investigation of Phase Noise in Monolithically Integrated Gain-Switched Lasers
Résumé:
Phase noise in gain-switched lasers is investigated theoretically using the semiconductor laser rate equations and compared with the experimental results from monolithically integrated devices. The phase noise of a gain-switched laser is modelled both with and without injection-locking using the rate equations for a single-mode laser. Phase noise is found to increase with gain-switching, and decrease when injection-locked to a master laser. This trend is then observed experimentally on-chip with monolithically integrated devices without the use of an isolator.
Auteurs: Justin K. Alexander;Padraic E. Morrissey;Ludovic Caro;Mohamad Dernaika;Niall P. Kelly;Frank H. Peters;
Apparue dans: IEEE Photonics Technology Letters
Date publication: 05.-2017, volume: 29, issue:9, pages: 731 - 734
Editeur: IEEE
Document complet vers site de l'éditeur
 
» Online Condition Monitoring for Both IGBT Module and DC-Link Capacitor of Power Converter Based on Short-Circuit Current Simultaneously
Résumé:
Insulated-gate bipolar transistor (IGBT) modules and dc-link capacitors are important parts in the majority of power electronic converters which contribute to cost, size, and failure rate on a considerable scale. This paper presents an online condition monitoring method for both IGBT modules and dc-link capacitors of power converters based on short-circuit current of an IGBT module, which is a good condition indicator according to the theory analysis. The failure prediction of dc-Link capacitor is realized by equivalent series resistance, which can be calculated by short-circuit current and a step voltage, and the bond wires fatigue can also be identified by the short-circuit current. The proposed method is capable for detecting small changes in the failure indicators of IGBT modules and electrolytic capacitors, and its effectiveness is validated by a confirmatory experiment. The novelty of the proposed method is that the degradations of IGBT modules and capacitors can be identified simultaneously, and has the merits of low cost and circuit simplicity
Auteurs: Pengju Sun;Can Gong;Xiong Du;Quanming Luo;Haibo Wang;Luowei Zhou;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 3662 - 3671
Editeur: IEEE
Document complet vers site de l'éditeur
 
» Online Optimal Operation of Parallel Voltage-Source Inverters Using Partial Information
Résumé:
In this paper, a novel optimal learning algorithm for partially unknown voltage-source inverters (VSIs) operating in parallel is presented. The algorithm designs game-theory-based distributed controllers to provide the appropriate working voltage magnitude and frequency at the load by converting dc voltage to ac voltage at the parallel VSIs. It takes advantage of information from the neighboring low pass $Lhbox{-}C$ filters to improve harmonic distortion and guarantee equal sharing of the load current across the VSIs while avoiding current circulation during transient and ensuring stability and robustness. It builds upon the ideas of approximate dynamic programming (ADP) and uses only partial information of the system and the exosystem, which is connected only to some of the VSIs. The proposed framework was tested in simulations to show its effectiveness.
Auteurs: Kyriakos G. Vamvoudakis;João P. Hespanha;
Apparue dans: IEEE Transactions on Industrial Electronics
Date publication: 05.-2017, volume: 64, issue:5, pages: 4296 - 4305
Editeur: IEEE
Document complet vers site de l'éditeur
 
» Online Ski Rental for ON/OFF Scheduling of Energy Harvesting Base Stations
Résumé:
The co-existence of small cell base stations (SBSs) with conventional macrocell base station is a promising approach to boost the capacity and coverage of cellular networks. However, densifying the network with a viral deployment of SBSs can significantly increase energy consumption. To reduce the reliance on unsustainable energy sources, one can adopt self-powered SBSs that rely solely on energy harvesting. Due to the uncertainty of energy arrival and the finite capacity of energy storage systems, self-powered SBSs must smartly optimize their ON and OFF schedule. In this paper, the problem of ON/OFF scheduling of self-powered SBSs is studied, in the presence of energy harvesting uncertainty with the goal of minimizing the operational costs consisting of energy consumption and transmission delay of a network. For the original problem, we show that an algorithm can solve the problem in the illustrative case. Then, to reduce the complexity of the original problem, an approximation is proposed. To solve the approximated problem, a novel approach based on the ski rental framework, a powerful online optimization tool, is proposed. Using this approach, each SBS can effectively decide on its ON/OFF schedule autonomously, without any prior information on future energy arrivals. By using competitive analysis, a deterministic online algorithm and a randomized online algorithm (ROA) are developed. The ROA is then shown to achieve the optimal competitive ratio in the approximation problem. Simulation results show that, compared with a baseline approach, the ROA can yield performance gains reaching up to 15.6% in terms of reduced total energy consumption of SBSs and up to 20.6% in terms of per-SBS network delay reduction. The results also shed light on the fundamental aspects that impact the ON time of SBSs while demonstrating that the proposed ROA can reduce up to 69.9% the total cost compared with a bas- line approach.
Auteurs: Gilsoo Lee;Walid Saad;Mehdi Bennis;Abolfazl Mehbodniya;Fumiyuki Adachi;
Apparue dans: IEEE Transactions on Wireless Communications
Date publication: 05.-2017, volume: 16, issue:5, pages: 2976 - 2990
Editeur: IEEE
Document complet vers site de l'éditeur
 


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