#### Electrical and Electronics Engineering publications abstract of: 10-2017 sorted by title, page: 4

» Analog Coded SoftCast: A Network Slice Design for Multimedia Broadcast/Multicast
 Abstract:This paper presents a network slice design for ultra high definition (UHD) video broadcast/multicast to achieve higher network efficiency and improved quality of experience (QoE). The proposed network slice design consists of a rateless source compression scheme and an analog-coded SoftCast scheme. The rateless Spinal code is adopted to compress the video source at content server and the compressed source is transmitted from content server across wireless core network to the base station. An a priori information-assisted Spinal decoder is designed to utilize the sparsity of bit planes for compression. In the analog-coded SoftCast scheme, we design a new chaotic function-based analog code with negligible power penalty for the generalized Gaussian-distributed source in SoftCast because the existing chaotic functions designed for uniformly distributed sources suffer from serious power penalty in SoftCast. We also design a maximum a posteriori probability decoding algorithm for the proposed analog code in order to exploit the statistics of video source as a priori information to improve the performance. The experimental results show that the proposed rateless code-based compression scheme achieves efficient compression and approaches the bound of binary erasure channel. In particular, the 1/2 analog-coded SoftCast has almost 2 dB gain over conventional SoftCast with two repetitions, and the 1/3 analog-coded SoftCast has almost 3 dB gain over conventional SoftCast with three repetitions. The system simulations for the broadcast system show higher network capacity and improved QoE in the proposed UHD slice, because the reconstructed video quality of each user is commensurate with its channel condition. Autors: Bin Tan;Jun Wu;Ying Li;Hao Cui;Wei Yu;Chang Wen Chen; Appeared in: IEEE Transactions on Multimedia Publication date: Oct 2017, volume: 19, issue:10, pages: 2293 - 2306 Publisher: IEEE
» Analysis and Design of Bang-Bang PD-Based Phase Noise Filter
 Abstract:In this paper, we present a bang-bang phase detector (BBPD) and a delay-line frequency discriminator-based phase noise filter (PNF). With a larger phase detection gain, the BBPD-based PNF enhances the sensitivity by suppressing the charge pump noise. A time-amplifier and a five times voting machine are introduced together with the sense-amplifier-flip-flop to minimize the BBPD noise to make its effects negligible in the PNF sensitivity. At 1-MHz offset, the PNF demonstrates 15-dB phase noise suppression with −120.2-dBc/Hz sensitivity. Its phase noise suppression offset frequency is from 100 kHz to 8 MHz with 10–10.1-GHz input frequency range. The circuit is fabricated in a 65-nm CMOS technology, and dissipates 98-mW power. Autors: Tongning Hu;Shilei Hao;Qun Jane Gu; Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers Publication date: Oct 2017, volume: 64, issue:10, pages: 2703 - 2713 Publisher: IEEE
» Analysis and Design of Closed-Loop Control of Electrolytic Capacitor-Less Six-Pulse DC Link Three-Phase Inverter
 Abstract:Three-phase inverters in uninterrupted power supply, electric vehicles, and hybrid electric vehicles use an intermediate dc-link electrolytic capacitor, which has reliability issues and is one prominent cause of inverter failure and limited life. The large volume of an electrolytic capacitor increases the size and cost of the system. Recent research on electrolytic capacitorless inverters using six-pulse modulation technique along with high-frequency power conversion has attempted to address this issue. However, closed-loop operation and control has some issues due to capacitorless dc-link. In this paper, closed-loop operation, design, and implementation of an electrolytic capacitorless inverter is presented. A proof-of-concept 1-kW hardware prototype has been built and tested in a laboratory under different loading conditions. In total, 98% rated efficiency of the inverter is obtained with total harmonic distortion within 2%. Transient results during start-up and load change are smooth, demonstrating safe operation of the inverter. Autors: Anirban Ghoshal;Xuewei Pan;Akshay K Rathore; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4957 - 4964 Publisher: IEEE
» Analysis and Design of the Ladder Resonant Switched-Capacitor Converters for Regulated Output Voltage Applications
 Abstract:The traditional Ladder switched-capacitor converters have the issues of hard-switching operation and poor line regulation capability. By adding a resonant inductor and substituting a bulky capacitor bank with a small resonant capacitor, its resonant configuration can be obtained and the aforementioned issues could be solved. In addition, by operating the Ladder resonant switched-capacitor converters (RSCs) above the resonance, the optimized operation region is found and some transformational changes can be obtained: the transistors can be operated with zero voltage switching turn-on and diodes are zero current switching turned on/off; the line regulation range is increased significantly for regulated output voltage applications; the instability issue of transition between discontinuous current mode and continuous current mode can be avoided with closed loop; and the voltage/current stress of the resonant tank is reduced. Extensive analysis above and below the resonance is presented to reveal the converter operation modes, voltage-gain curves, output characteristics, and voltage/current stress of the resonant tank. A 3X Ladder RSC prototype for an electronic fuel injection application with maximum output voltage 150 V, maximum power 140 W and peak efficiency 97.6% was designed to be operating in the optimized operation region. The analysis is verified by experimental results. Autors: Shouxiang Li;Kang Xiangli;Yifei Zheng;Keyue Ma Smedley; Appeared in: IEEE Transactions on Industrial Electronics Publication date: Oct 2017, volume: 64, issue:10, pages: 7769 - 7779 Publisher: IEEE
» Analysis of a Direct Antenna Modulation Transmitter for Wideband OOK With a Narrowband Antenna
 Abstract:The characteristics of a narrowband antenna transmitting a broadband on–off-keyed signal using direct antenna modulation (DAM) are studied. The DAM technique has previously been proposed to generate a broadband signal using a rapidly time-varying antenna, but the signals produced using this technique and its limitations are not well understood. In this paper, we quantitatively compare the performance of a DAM transmitter to a conventional time-invariant transmit antenna. We show that the fall time of an RF pulse produced with the DAM configuration is measurably shorter than with the conventional system; however, the pulse rise time using both systems is identical. The performance of each system is then analyzed in terms of the bit error rate over a simple point-to-point link using analytical models, numerical simulation, and measurement. DAM reduces the intersymbol interference (ISI) by reducing the discharging time; however, the overall performance remains similar to the conventional system because of their similar charging times. While the DAM configuration does radiate a qualitatively broader spectrum as observed in previous studies, this does not translate into quantitative improvement in the characteristics of a transmitted data signal. Autors: Shruti Srivastava;Jacob J. Adams; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 4971 - 4979 Publisher: IEEE
» Analysis of Distribution Using Graphical Goodness of Fit for Airborne SAR Sea-Clutter Data
 Abstract:For radar target detection, the clutter distribution model needs to be identified first. The goodness of fit (GoF) between the original data and the assumed distribution can be used to choose the proper distribution model. Generally, the GoF is obtained using data histogram and theoretical distribution curve, and then the distribution model is judged via GoF. However, when the sample number is small, the histogram is rough and fluctuating, affecting the analysis of GoF. For the small sample, the graphical characteristic is obtained with the sample data to choose the most fitting distribution to the data in this paper. The graphical characteristic is acquired by a simpler process, that is, the original data are directly set as the test statistics, avoiding computing and sorting of other statistics. In this paper, the real airborne circular synthetic aperture radar data under different scan angles are analyzed using the GoF corresponding to histogram and graphical GoF, respectively. The results show that when the sea-clutter data histogram is close to two distributions, a more fitting distribution model may not be obtained by traditional GoF, but can be acquired by graphical representation. In addition, the sea data with different sight angles have different match properties. It is seen that the sea data are closer to the Rayleigh distribution in side-looking mode than that in big squint-angle mode, while the Weibull distribution and K distribution show equal fitting performance to sea clutter under variant radar sight angles. Autors: Zhihui Xin;Guisheng Liao;Zhiwei Yang;Yuhong Zhang;Hongxing Dang; Appeared in: IEEE Transactions on Geoscience and Remote Sensing Publication date: Oct 2017, volume: 55, issue:10, pages: 5719 - 5728 Publisher: IEEE
» Analysis of Leakage Loss in Silicon Photonics with Finite Gain Compensation
 Abstract:Silicon waveguides fabricated on silicon-on-insulator wafers are leaky in nature. This fact puts a lower bound on the insulator thickness in silicon photonic structures as integrated with compact electronic devices. We examine this constraint from the angle of finite gain compensation for leakage loss using III-V semiconductor gain media bonded to passive silicon waveguides. With a reasonable magnitude of available gain, we find that an insulator layer thinner than 320 nm could support the fundamental quasi-transverse-electric mode of silicon waveguides with a core thickness around 170 nm. This may enable the integration of photonic devices with compact electronic counterparts for radio-frequency and analog applications. Furthermore. size reductions to the level of partially depleted electronic devices might be possible if the leakage loss need not be fully compensated, or the gain limit could be raised Autors: Po-Jui Chiang;Tien-Tsorng Shih; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 10 Publisher: IEEE
» Analysis of Multi-Server Queue With Spatial Generation and Location-Dependent Service Rate of Customers as a Cell Operation Model
 Abstract:A novel multi-server queue with heterogeneous customers is formulated and analyzed as the model of operation of a cell of a mobile communication network. We assume that the cell is divided into zones depending on signal quality. The type of a customer corresponds to a zone in which this customer is currently situated and the rate of the customer’s service depends on his/her type. During service, the customer may transit to another zone or terminate service (e.g., owing to poor service quality or departure from the cell). The stationary distribution of the system states and the key performance measures of the system are computed. Numerical results are presented. Autors: Sergei Dudin;Chesoong Kim; Appeared in: IEEE Transactions on Communications Publication date: Oct 2017, volume: 65, issue:10, pages: 4325 - 4333 Publisher: IEEE
» Analysis of Path-Length Effects in Multiloop Cross-Eye Jamming
 Abstract:The effect of path-length differences on multiloop retrodirective cross-eye jammers is evaluated. It is shown that such jammers may act as beacons, and the conditions under which this occurs are investigated for two-loop jammers. The sensitivity of the two-loop cross-eye gain to path-length differences is also studied and is found to be small for small path-length differences, but to increase rapidly. The effect of the two-loop cross-eye jammer parameters on path-length effects is also considered. Autors: Warren Paul du Plessis; Appeared in: IEEE Transactions on Aerospace and Electronic Systems Publication date: Oct 2017, volume: 53, issue:5, pages: 2266 - 2276 Publisher: IEEE
» Analysis of Performance Optimization for a Microwave Photonic Filter Based on Stimulated Brillouin Scattering
 Abstract:A single passband microwave photonic filter (MPF) based on stimulated Brillouin scattering (SBS) is analyzed and experimentally demonstrated. The proposed MPF can be tuned over a dramatically large frequency range, which overcomes the disadvantage in previously reported schemes based on SBS that the frequency tuning range is limited within two folds of the Brillouin frequency shift. The single passband MPF is obtained by enhancing the amplitude of the microwave passband generated by SBS gain while suppressing the amplitude of the microwave passband generated by SBS loss through optimizing the key parameters of the SBS process, including the pump power, the length of high nonlinear fiber, and the polarization states of the pump and signal waves. A theoretical model is established to describe the operation principle of the SBS-based MPF and illustrate the mechanism for the single passband, and an experiment is carried out to verify the theoretical analysis. In the experiment, the central frequency of the single passband MPF can be tuned from 0 to 40 GHz, which is only limited by the bandwidth of the adopted electro-optic modulator and photodetector. The main to secondary sidelobe ratio can reach 55 dB and the full width at half-maximum bandwidth is 16 MHz. The achieved MPF is specifically suitable for applications in ultrahigh selective filtering. Autors: Haitao Tang;Yuan Yu;Chi Zhang;Ziwei Wang;Lu Xu;Xinliang Zhang; Appeared in: Journal of Lightwave Technology Publication date: Oct 2017, volume: 35, issue:20, pages: 4375 - 4383 Publisher: IEEE
» Analysis of PM Transverse-Flux Outer Rotor Machines With Different Configuration
 Abstract:This paper presents the electromagnetic analysis of two permanent magnet transverse-flux outer rotor machines with and without magnetic shunts. The research started with designing and analyzing a permanent magnet transverse-flux machine with an inner rotor, previously patented by J. Giearas in 2010. However, the results obtained from the prototype test differed significantly from the estimated results. Applying three-dimensional (3-D) finite element method (FEM), the main problem of the machine was detected. The problem was in high flux leakage that weakened magnetic flux density in the stator poles. Such observation led to designing two machines with outer rotor, with and without magnetic shunts. The role of the magnetic shunts is to minimize flux leakage in the stator in order to improve the performance of the machine. Electromechanical parameters of both outer rotor machines, with and without magnetic shunts, are compared in the paper. Three-D FEM results are supported by laboratory analysis of the machines’ prototypes. Experimental measurements proved that the machine with magnetic shunts demonstrated better performance as compared with the machine without magnetic shunts. Presence of the magnetic shunts in the machine resulted in reducing of flux leakage and cogging torque. Autors: Oleksandr Dobzhanskyi;Rupert Gouws;Ebrahim Amiri; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4260 - 4268 Publisher: IEEE
» Analysis of Temperature Effects on Performance of Interior Permanent Magnet Machines for High Variable Temperature Applications
 Abstract:The purpose of this paper is to analyze and investigate the influence of temperature variation on the characteristics and performance of interior permanent magnet (IPM) machines. The impact of temperature variation on the materials of IPM machines is discussed to show the sources of performance variation. The flux linkages, torque output capability, and inductance variation as functions of the temperature are analyzed and discussed. This paper also shows the influence of temperature variation on key IPM machines performance including constant torque curves, voltage limit ellipses, maximum torque per ampere trajectories, and torque–speed curves. Experimental results of a traction IPM machine verified the analysis and theory. The results and trends shown in this paper set a foundation for developing control algorithm, which takes the temperature effects into consideration, especially in the applications where operating temperature varies significantly. Autors: Silong Li;Bulent Sarlioglu;Sinisa Jurkovic;Nitin R. Patel;Peter Savagian; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4923 - 4933 Publisher: IEEE
» Analysis on the Rapid Recovery of Irradiated VDMOSFETs by the Positive High Electric Field Stress
 Abstract:High electric field stress (HEFS) and annealing effects on irradiated (by 60Co -ray) vertical double-diffused MOSFETs (VDMOSFETs) are investigated. The behaviors of the oxide-trapped charges and interface traps during the stress are measured by using a simplified midgap technique. Rapid recovery of the threshold voltage () for the irradiated VDMOSFET is observed under a positive high electric field stress (PHEFS). The results show that the densities of oxide-trapped charges and interface traps decreased more rapidly for the PHEFS than that for postirradiation annealing. Repeated irradiation results of PHEFS-recovered VDMOSFETs indicate the possibility of reusing the irradiated VDMOSFETs. Autors: Ling Peng;Dongqing Hu;Yunpeng Jia;Yu Wu;Pengzhen An;Guo Jia; Appeared in: IEEE Transactions on Nuclear Science Publication date: Oct 2017, volume: 64, issue:10, pages: 2633 - 2638 Publisher: IEEE
» Analytical Formulas for Artificial Dielectrics With Nonaligned Layers
 Abstract:In this paper, we present analytical models to describe artificial dielectric layers (ADLs), when a lateral shift between layers is present. The alternate lateral displacement between layers is an important parameter to engineer the desired effective electromagnetic properties of the equivalent homogeneous material realized with the ADLs. More specifically, the equivalent dielectric constants that can be realized by alternatively shifting the layers are higher compared with the aligned case. Closed-form expressions are derived for the equivalent layer reactance that includes the higher order interaction between shifted layers. The given analytical formulas can be used to derive an equivalent circuit model that describes the scattering parameters of a plane wave impinging on a slab composed by an arbitrary finite number of metal layers. To aid the design of artificial dielectric slabs, the effective permittivity and permeability tensors are also retrieved from the scattering parameters. Autors: Daniele Cavallo;Cantika Felita; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 5303 - 5311 Publisher: IEEE
» Analytical Insights Into Parameter Estimation for Wiener Deconvolution
 Abstract:All real-time signals observed from various measurement systems require signal-processing techniques like the deconvolution, to compensate for the effect of transfer function of the systems. Wiener deconvolution is a widely used signal-processing technique for signal restoration. Often, if the power spectral density of signal and noise is unknown, the accuracy of the restored signal depends on an unknown filter parameter. In the literature, time-consuming, iterative, computational methods were reported to estimate the parameter. However, many of these methods give a range of optimum values instead of an unique value and often lead to either over-smoothing or under-smoothing. In this paper, novel analytical expressions are presented through which the unknown parameter can be estimated explicitly. The analytical results of this study are compared with the numerical methods, and they are found to be accurate and robust against numerical evaluation. Further, the results are demonstrated for signals obtained experimentally from the pulsed electroacoustic system and a network, in authors’ laboratory. Autors: Ashish Gupta;Chandupatla Chakradhar Reddy; Appeared in: IEEE Transactions on Instrumentation and Measurement Publication date: Oct 2017, volume: 66, issue:10, pages: 2566 - 2575 Publisher: IEEE
» Analytical Modeling of Mutually Coupled Switched Reluctance Machines Under Saturation Based on Design Geometry
 Abstract:An analytical calculation of the winding flux linkages and torque is proposed for fully pitched mutual coupled switched reluctance motors to develop a machine model without using numerical methods. The proposed technique is not empirical and does not require any finite-element analysis (FEA). The design parameters and the material properties of the machine are the only inputs to the model, which can predict the winding flux linkages and torque at any phase currents and rotor positions. The model is applicable for the rotor positions where the stator and rotor poles overlap. Initial assumptions and then the step-by-step procedure for flux linkage, co-energy, and torque calculations are provided. The flux linkages and torque predicted through the proposed modeling technique are compared with the FEA results. Finally, experimental results of flux linkage and torque are provided to verify the accuracy of the proposed modeling technique. Autors: Wasi Uddin;Yilmaz Sozer; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4431 - 4440 Publisher: IEEE
» Analyzing Graphene-Based Absorber by Using the WCS-FDTD Method
 Abstract:A weakly conditionally stable finite-difference time-domain (WCS-FDTD) method is used to simulate a graphene-based absorber. By using the auxiliary differential equation and Padé fitting method, both the interband and intraband conductivities of the graphene are incorporated into the WCS-FDTD method. The time step increment in the proposed method is not determined by the fine meshes in the graphene layer, so the computational efficiency of this method is greatly improved from that of the conventional FDTD method. By using the proposed WCS-FDTD method, a graphene-based absorber is simulated and analyzed. The numerical result shows that the graphene can achieve tunable absorption through controlling its chemical potential, and the interband conductivity of the graphene has important effects on the performance of the absorber. Autors: Juan Chen;Jianxing Li;Qing Huo Liu; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3689 - 3696 Publisher: IEEE
» Analyzing Interfaces and Workflows for Light Field Editing
 Abstract:With the increasing number of available consumer light field cameras, such as Lytro, Raytrix, or Pelican Imaging, this new form of photography is progressively becoming more common. However, there are still very few tools for light field editing, and the interfaces to create those edits remain largely unexplored. Given the extended dimensionality of light field data, it is not clear what the most intuitive interfaces and optimal workflows are, in contrast with well-studied two-dimensional (2-D) image manipulation software. In this work, we provide a detailed description of subjects’ performance and preferences for a number of simple editing tasks, which form the basis for more complex operations. We perform a detailed state sequence analysis and hidden Markov chain analysis based on the sequence of tools and interaction paradigms users employ while editing light fields. These insights can aid researchers and designers in creating new light field editing tools and interfaces, thus helping to close the gap between 4-D and 2-D image editing. Autors: Marta Ortín;Adrian Jarabo;Belen Masia;Diego Gutierrez; Appeared in: IEEE Journal of Selected Topics in Signal Processing Publication date: Oct 2017, volume: 11, issue:7, pages: 1162 - 1172 Publisher: IEEE
» Analyzing the Stability of Switched Systems Using Common Zeroing-Output Systems
 Abstract:This paper introduces the notion of common zeroing-output systems (CZOS) to analyze the stability of switched systems. The concept of CZOS allows one to verify weak zero-state detectability. It characterizes a common behavior of any individual subsystem when the output signal for each subsystem is “approaching” zero. Heuristically speaking, it removes the effect of switching behavior, and thus enables one to analyze stability properties in systems with complex switching signals. With the help of CZOS, the Krasovskii–LaSalle theorem can be extended to switched nonlinear time-varying systems with both arbitrary switching and more general restricted switching cases. For switched nonlinear time-invariant systems, the needed detectability condition is further simplified, leading to several new stability results. Particularly, when a switched linear time-invariant system is considered, it is possible to generate a recursive method, which combines a Krasovskii–LaSalle result and a nested Matrosov result, to find a CZOS if it exists. The power of the proposed CZOS is demonstrated by consensus problems in literature to obtain a stronger convergence result with weaker conditions. Autors: Ti-Chung Lee;Ying Tan;Iven Mareels; Appeared in: IEEE Transactions on Automatic Control Publication date: Oct 2017, volume: 62, issue:10, pages: 5138 - 5153 Publisher: IEEE
» Angle Domain Hybrid Precoding and Channel Tracking for Millimeter Wave Massive MIMO Systems
 Abstract:The millimeter-wave (mm-wave) massive multiple-input multiple-output (MIMO) system has gained much attention for its considerable improvement in system throughput. However, the cost of complex hardware, e.g., radio frequency (RF) chains, hinders it from practical deployment. In this paper, we propose an angle domain hybrid precoding and channel tracking method by exploring the spatial features of the mm-wave massive MIMO channel. The number of the effective spatial beams, or equivalently the RF chains, is enormously decreased via the operation of spatial rotation. The users are then scheduled by the angle division multiple access scheme, which groups users according to their direction of arrivals (DOAs). Meanwhile, a channel tracking method is designed for the subsequent data transmission through a small number of pilot symbols. Specifically, the channel information is divided into the DOA information and the gain information, where the DOA information is tracked by a modified unscented Kalman filter and the gain information is estimated from beam training. Numerical results are provided to corroborate our studies. Autors: Jianwei Zhao;Feifei Gao;Weimin Jia;Shun Zhang;Shi Jin;Hai Lin; Appeared in: IEEE Transactions on Wireless Communications Publication date: Oct 2017, volume: 16, issue:10, pages: 6868 - 6880 Publisher: IEEE
» Angle-of-Arrival Estimation of Broadband Microwave Signals Based on Microwave Photonic Filtering
 Abstract:We propose and experimentally demonstrate a photonic approach to estimate the angle-of-arrival (AOA) of broadband microwave signals. Using an integrated polarization-division multiplexing Mach–Zehnder modulator and a differential group-delay module, a microwave photonic notch filter is constructed. The relative time delay in reception of the signal at two separate antenna elements can be obtained by measuring the transmission notches over the signal spectra. The AOA is calculated from the relative time delay and the antenna spacing. The experiment results show that the measurement error is less than ±0.35 ps when the relative time delay changes from −14 to 16 ps. Autors: Zhaoyang Tu;Aijun Wen;Zhongguo Xiu;Wu Zhang;Mei Chen; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 8 Publisher: IEEE
» Anisotropic Discrete Dual-Tree Wavelet Transform for Improved Classification of Trabecular Bone
 Abstract:This paper deals with a new anisotropic discrete dual-tree wavelet transform (ADDTWT) to characterize the anisotropy of bone texture. More specifically, we propose to extend the conventional discrete dual-tree wavelet transform (DDTWT) by using the anisotropic basis functions associated with the hyperbolic wavelet transform instead of isotropic spectrum supports. A texture classification framework is adopted to assess the performance of the proposed transform. The generalized Gaussian distribution is used to model the distribution of the sub-band coefficients. The estimated vector of parameters for each image is then used as input for the support vector machine classifier. Experiments were conducted on synthesized anisotropic fractional Brownian motion fields and on a real database composed of osteoporotic patients and control cases. Results show that the ADDTWT outperforms most of the competing anisotropic transforms with an area under curve rate of 93%. Autors: Hind Oulhaj;Mohammed Rziza;Aouatif Amine;Hechmi Toumi;Eric Lespessailles;Mohammed El Hassouni;Rachid Jennane; Appeared in: IEEE Transactions on Medical Imaging Publication date: Oct 2017, volume: 36, issue:10, pages: 2077 - 2086 Publisher: IEEE
» Antenna Deembedding for mmWave Propagation Modeling and Field Measurement Validation at 73 GHz
 Abstract:In field measurements at millimeter-wave (mmWave) frequencies, the spatial propagation characteristics are usually obtained by using steerable high-gain horn antennas to compensate the large path loss. However, it is a challenging issue to deembed antenna patterns from the observed channel responses. This paper has two contributions. First, according to the steering-antenna sounding process, a spatial channel response model is designed, where the multipath propagation profile, antenna pattern, and channel response are spatially sampled and combined in a discrete convolutional form. Then, a low-complexity antenna deembedding algorithm, including two steps of deconvolutions, is proposed. Second, a field measurement campaign on the frequency-space mmWave channels in an office is presented to validate the method. The channels were sounded at 72.5 to 73.5 GHz using three horn antennas with different beam widths and gains. The omnidirectional angular channel responses (ACRs) were measured by rotating the receiver antenna. The observed and reconstructed ACRs are consistent, and the estimated antenna-free angular propagation profiles by using different horn antennas are also highly correlated, which validate the proposed antenna deembedding approach. Furthermore, the omnidirectional transfer functions in the mmWave band obtained using different horn antennas are compared, and the channel coherence bandwidth is analyzed based on the autocorrelation of the transfer functions. Autors: Ruonan Zhang;Yuliang Zhou;Xiaofeng Lu;Chang Cao;Qi Guo; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3648 - 3659 Publisher: IEEE
» Anti-Islanding Protection Relay for Medium Voltage Feeder With Multiple Distributed Generators
 Abstract:Large distributed generators (DGs) are usually connected to medium voltage (MV, typically up to 50 kV) feeders directly. Their anti-islanding protections mainly rely on transfer trips from upstream substations through communication media, which are expensive and time-consuming because of infrastructure. This paper presents a local anti-islanding protection relay (LPR) as an alternative for the traditional transfer trip in MV feeder applications. The basic idea of the proposed LPR is to short phase to neutral or phase to phase voltages by thyristors at the point of common coupling (PCC) of each DG when either of them is crossing zero; then both variations of the thyristor current and voltage harmonic distortion at the PCC are observed and measured, and they are able to indicate the operating mode of the DG unit in either grid-connected or islanding. Further, this approach is analyzed and discussed based on a single DG scenario and a complicated scenario with two DGs and one shunt capacitor bank. Finally, a lot of experiment results with different scenarios are obtained based on a scale-down testing platform, which has been built in our lab by using per-unit method from an actual MV feeder system. Autors: Hua F. Xiao;Zhijian Fang;Dewei Xu;Bala Venkatesh;Birendra Singh; Appeared in: IEEE Transactions on Industrial Electronics Publication date: Oct 2017, volume: 64, issue:10, pages: 7874 - 7885 Publisher: IEEE
» Aperture Distributions for Maximum Endfire Directivity From a Continuous Line Source With a Uniform Phase Progression
 Abstract:An optimized aperture distribution is investigated to achieve the maximum endfire directivity for a continuous line source with a uniform phase progression. The optimization method has the advantages of simplicity and efficiency, in which the aperture distribution is expanded into a set of cosine functions and the optimization reduces to solving a constrained linear-least-squares problem. Based on the copious computed results from the optimization, an approximate closed-form expression is derived for the maximum directivity. The expression can serve as a bound for the endfire directivity for a line source with a uniform phase progression. It is found that the optimum directivity increases almost linearly with an increase of the normalized phase constant, but with a decrease in the radiated power. Nevertheless, the enhancement in the directivity is much higher than that in previously studied superdirectivity, under the same constraint in the ratio of reactive to radiated power. The current distribution does not oscillate widely as is does for superdirectivity, and is therefore more practical than for superdirectivity. Autors: Juhua Liu;David R. Jackson; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 5123 - 5136 Publisher: IEEE
» Applicability of LED-Based Excitation Source for Defect Depth Resolved Frequency Modulated Thermal Wave Imaging
 Abstract:This paper proposes an energy efficient instrumentation set-up for pulse-compression thermal-wave imaging with a low-power LED excitation source. The set-up consists of three different subsystems that are synchronised in time. The individual systems consist of a LED modulation circuitry, reference signal measurement circuitry, and an IR camera trigger signal generation circuitry for frame capture. A separate reference acquisition circuitry is useful in quantifying defect depth resolution. This paper also proposes a nonuniform frame capture technique to reduce the memory allocation space of the recorded video. The technique is based on varying the sampling rate with a change in instantaneous frequency and is specifically useful for frequency modulated excitation signal. The proposed technique is implemented on a carbon fiber reinforced polymer test-piece. The variation of pulse compression parameters with different defect dimension is studied, and the results are verified with an electro-thermal simulator. Further, an objective comparison of pulse compression experiment for different experiment duration is presented. Autors: Deboshree Roy;Suneet Tuli; Appeared in: IEEE Transactions on Instrumentation and Measurement Publication date: Oct 2017, volume: 66, issue:10, pages: 2658 - 2665 Publisher: IEEE
» Application of the Curvelet Transform for Clutter and Noise Removal in GPR Data
 Abstract:This paper presents a new method based on the curvelet transform to improve the readability of ground penetrating radar (GPR) data during localization works of buried pipes. The localization is achieved by the detection of hyperbolas in the GPR cross section, also called B-scan. However, GPR antenna collects abundant information from the ground, which can partially hide useful information, especially echoes from the pipes (i.e., hyperbolas). In order to highlight these echoes, it is important to reduce noise and to remove undesirable items such as the clutter and column artifacts. For this purpose, we propose to use the curvelet transform in a three processing step method: clutter, noise, and column artifact removal. Thanks to prior information on the distribution of the coefficients and on the orientation of the clutter and artifacts, we are able to reduce them in the B-scan. These steps can be used independently giving more flexibility to the operator. Moreover, the processing is fast to compute and requires only one easily tunable parameter. This is appropriate for a computation in real-time by nonexpert operators. Our method has been applied to real data acquired on a test area and under real conditions. We show the proposed method presents satisfying qualitative and quantitative results compared to other methods. Autors: Guillaume Terrasse;Jean-Marie Nicolas;Emmanuel Trouvé;Émeline Drouet; Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Publication date: Oct 2017, volume: 10, issue:10, pages: 4280 - 4294 Publisher: IEEE
» Applying Transmission Line Theory to Study the Transmitting Turn-OFF Current in a Long Grounded Wire
 Abstract:A long grounded wire in the transient electromagnetic (TEM) surveys is usually considered by using the lumped parameter circuit model, which fails to explicate the early turn-OFF current with crucial importance for TEM surveys. In this paper, the transmission line model is introduced for the first time to explicate the early turn-OFF current in the long grounded wire considering the high frequency at early turn-OFF stage. The transmission line model suitable for the long grounded wire is constructed, then the calculation formulas of the distributed parameters and load impedance are analyzed, and the transfer function utilized to simulate the current at any position of the transmission line is also derived. The simulation is performed in the frequency domain with subsequent transformation into the time domain, and the simulation results are in good agreement with the experimental data. The early turn-OFF currents depending on the earth resistivity vary with the position in the long grounded wire. Therefore, the early time TEM response differs from that predicted by the classical theory of the TEM surveys. This proposed model can guide the realization of the minimum current turn-OFF duration, which will help to reduce the detection blind spot and this paper provides new ideas and prospects for early response data and current waveform data for interpretation in the geophysics detection. Autors: Zongyang Shi;Lihua Liu;Pan Xiao;Zhi Geng;Guangyou Fang; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 5112 - 5122 Publisher: IEEE
» Approximate Mean Delay Analysis for a Signalized Intersection With Indisciplined Traffic
 Abstract:Mixed vehicular traffic comprising small cars and two-wheeled vehicles (called motorcycles in this paper) arrive at a lane of a signalized road intersection. The traffic does not follow lane-discipline, in that the arriving vehicles do not necessarily queue up one behind the other. The motorcycles are small enough to stand side-by-side with cars or other motorcycles, so as to fill up the width of the lane. With such queue joining behavior, the waiting vehicles form batches, comprising motorcycles, and at most one car. During the green signal period the vehicles in the head-of-the-line batch exit the intersection together. In this paper, assuming a Poisson point process model for vehicle arrivals, we have provided an approximate analysis of such a queueing system. Our approach is to use an assembly queue model for the batching process. The batches generated by the assembly queue enter an interrupted M/SemiMarkov/1 (or M/SM/1) queue. By analyzing the assembly queue we characterize the batch input process for the interrupted M/SM/1 queue. We then develop an extension of the Webster mean delay formula for obtaining the approximate mean delay in the interrupted M/SM/1 queue. Numerical results from the analysis are compared with simulation results. The analysis is shown to be accurate in predicting the increase in the system capacity due to the batching behavior. Autors: Samrat Mukhopadhyay;Pramod M. J.;Anurag Kumar; Appeared in: IEEE Transactions on Intelligent Transportation Systems Publication date: Oct 2017, volume: 18, issue:10, pages: 2750 - 2762 Publisher: IEEE
» Approximation Algorithms for Charging Reward Maximization in Rechargeable Sensor Networks via a Mobile Charger
 Abstract:Wireless energy transfer has emerged as a promising technology for wireless sensor networks to power sensors with controllable yet perpetual energy. In this paper, we study sensor energy replenishment by employing a mobile charger (charging vehicle) to charge sensors wirelessly in a rechargeable sensor network, so that the sum of charging rewards collected from all charged sensors by the mobile charger per tour is maximized, subject to the energy capacity of the mobile charger, where the amount of reward received from a charged sensor is proportional to the amount of energy charged to the sensor. The energy of the mobile charger will be spent on both its mechanical movement and sensor charging. We first show that this problem is NP-hard. We then propose approximation algorithms with constant approximation ratios under two different settings: one is that a sensor will be charged to its full energy capacity if it is charged; another is that a sensor can be charged multiple times per tour but the total amount of energy charged is no more than its energy demand prior to the tour. We finally evaluate the performance of the proposed algorithms through experimental simulations. The simulation results demonstrate that the proposed algorithms are very promising, and the solutions obtained are fractional of the optimum. To the best of our knowledge, the proposed algorithms are the very first approximation algorithms with guaranteed approximation ratios for the mobile charger scheduling in a rechargeable sensor network under the energy capacity constraint on the mobile charger. Autors: Weifa Liang;Zichuan Xu;Wenzheng Xu;Jiugen Shi;Guoqiang Mao;Sajal K. Das; Appeared in: IEEE/ACM Transactions on Networking Publication date: Oct 2017, volume: 25, issue:5, pages: 3161 - 3174 Publisher: IEEE
» Arc Flash Visible Light Intensity as Viewed From Human Eyes
 Abstract:Human eye can be damaged by the intense light from an arc flash event. Though it is certain that high intensity visible light will be emitted during an arc flash event, there is limited research that provides quantitative light intensity estimation during different arcing incidents as viewed from human eyes. To provide better understanding of the light intensity during arc flash events, this paper proposes an arc flash light intensity estimation model based on approximately 1500 measurement data from arc flash tests using ambient light sensors, which are capable of measuring the light intensity of the arc flash as perceived by the human eyes. The proposed light intensity estimation model can be used to evaluate the potential impact of an arc flash on the human eyes. In addition, the autodarkening welding lens is used in the arc flash testing to explore its effectiveness in attenuating the light intensity and mitigating the exposure to the light hazard during an arc flash event. Autors: Shiuan-Hau Rau;Zhenyuan Zhang;Wei-Jen Lee;David A. Dini; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 5068 - 5077 Publisher: IEEE
» Architecture Design of a Memory Subsystem for Massive MIMO Baseband Processing
 Abstract:This brief presents an on-chip memory subsystem for massive multiple-input-multiple-output (MIMO) baseband processing at the base station. In massive MIMO systems, the required memory bandwidth and capacity are orders of magnitude higher than those used in conventional wireless systems, due to the large number of serving antennas. These are further combined with design targets on low access latency and flexibility in data organization and access modes. This brief applies and improves the concept of parallel memories to achieve the challenging design target with low hardware overhead. As a case study, a memory subsystem for 128-antenna and 16-user massive MIMO systems is evaluated using ST 28-nm technology. According to postlayout simulation results, the proposed memory subsystem provides 512-Gb/s throughput and offers 1-Mb capacity with a cost of 0.30 mm2. Autors: Yangxurui Liu;Liang Liu;Viktor Öwall; Appeared in: IEEE Transactions on Very Large Scale Integration Systems Publication date: Oct 2017, volume: 25, issue:10, pages: 2976 - 2980 Publisher: IEEE
» ARCNET Never Received Enough Credit [History]
 Abstract:In the March 2017 issue of IEEE Industrial Electronics Magazine, the authors of "The Future of Industrial Communication" provided a comprehensive chart of industrial communication milestones ranging from the 1960s to the present [1]. But there was one glaring omission-the Attached Resource Computer Network (ARCNET). As a former chair of the ARCNET Trade Association (ATA), I feel obligated to defend ARCNET as the first local area network (LAN), which is still in use today [2]. It is a technology that impacted both the office and industrial automation industries. It is elegant, fast, robust-and it works! The technology was deemed by the press as "the Rodney Dangerfield of network computing," and its proponents were called fanatical [3]. Although ARCNET has failed to receive the recognition it deserves, it is a successful technology that has been used in applications never imagined by its creators. Autors: George Thomas; Appeared in: IEEE Industry Applications Magazine Publication date: Oct 2017, volume: 23, issue:5, pages: 7 - 13 Publisher: IEEE
» Area/Energy-Efficient Gammatone Filters Based on Stochastic Computation
 Abstract:This paper introduces area/energy-efficient gammatone filters based on stochastic computation. The gammatone filter well expresses the performance of human auditory peripheral mechanism and has a potential of improving advanced speech communications systems, especially hearing assisting devices and noise robust speech-recognition systems. Using stochastic computation, a power-and-area hungry multiplier used in a digital filter is replaced by a simple logic gate, leading to area-efficient hardware. However, a straightforward implementation of the stochastic gammatone filter suffers from significantly low accuracy in computation, which results in a low dynamic range (a ratio of the maximum to minimum magnitude) due to a small value of a filter gain. To improve the computation accuracy, gain-balancing techniques are presented that represent the original gain as the product of multiple larger gains introduced at the second-order sections. In addition, dynamic scaling techniques are proposed that scales up small values only on stochastic domain in order to reduce the number of stochastic bits required while maintaining the computation accuracy. For performance comparisons, the proposed stochastic gammatone filters are designed and evaluated on taiwan semiconductor manufacturing company (TSMC) 65-nm CMOS technology. As a result, the proposed filter achieves an area reduction of 90.7% and an energy reduction of 91.8% in comparison with a fixed-point gammatone filter at the same sampling frequency and a comparable dynamic range. Autors: Naoya Onizawa;Shunsuke Koshita;Shuichi Sakamoto;Masahide Abe;Masayuki Kawamata;Takahiro Hanyu; Appeared in: IEEE Transactions on Very Large Scale Integration Systems Publication date: Oct 2017, volume: 25, issue:10, pages: 2724 - 2735 Publisher: IEEE
» Arrays of Position-Sensitive Virtual Frisch-Grid CdZnTe Detectors: Results From a $4times 4$ Array Prototype
 Abstract:Position-sensitive virtual Frisch-grid (VFG) CdZnTe (CZT) detectors offer a unique capability for correcting the response nonuniformities caused by crystal defects. This allowed us to achieve high energy resolution, while using typical-grade commercial CZT crystals with relaxed requirements to their quality, thus reducing the overall cost of detectors. Another advantage of the VFG detectors is that they can be integrated into arrays and used in small compact hand-held instruments or large-area gamma cameras that will enhance detection capability for many practical applications, including nonproliferation, medical imaging, and gamma-ray astronomy. Here, we present the results from testing small array prototypes coupled with front-end application-specified integrated circuit. Each detector in the array is furnished with 5-mm-wide charge-sensing pads placed near the anode. The pads signals are converted into XY coordinates, which combined with the cathode signals (for Z coordinates) provide 3-D position information of all interaction points. The basic array consists of a number of detectors grouped into subarrays, each having a common cathode made by connecting together the cathodes of the individual detectors. These features can significantly improve the performance of detectors while using typical-grade low-cost CZT crystals to reduce the overall cost of the proposed instrument. Autors: L. A. Ocampo Giraldo;A. E. Bolotnikov;G. S. Camarda;S. Cheng;G. De Geronimo;A. McGilloway;J. Fried;D. Hodges;A. Hossain;K. Ünlü;M. Petryk;V. Vidal;E. Vernon;G. Yang;R. B. James; Appeared in: IEEE Transactions on Nuclear Science Publication date: Oct 2017, volume: 64, issue:10, pages: 2698 - 2705 Publisher: IEEE
» Artificial Noise Injection for Securing Single-Antenna Systems
 Abstract:We propose a novel artificial noise (AN) injection scheme for wireless systems over quasi-static fading channels, in which a single-antenna transmitter sends confidential messages to a half-duplex receiver in the presence of an eavesdropper. Different from classical AN injection schemes, which rely on a multiantenna transmitter or external helpers, our proposed scheme is applicable to the scenario, where the legitimate transceivers are very simple. We analyze the performance of the proposed scheme and optimize the design of the transmission. Our results highlight that perfect secrecy is always achievable by properly designing the AN injection scheme. Autors: Biao He;Yechao She;Vincent K. N. Lau; Appeared in: IEEE Transactions on Vehicular Technology Publication date: Oct 2017, volume: 66, issue:10, pages: 9577 - 9581 Publisher: IEEE
» Assessment of the Influence of Losses on the Performance of the Electromagnetic Time Reversal Fault Location Method
 Abstract:Electromagnetic time reversal (EMTR) has been shown to be an efficient method for locating faults in ac and dc power grids. In the available literature, the back-propagation medium has been considered to have identical losses as the directtime medium. However, the telegrapher's equations describing the traveling wave propagation are time-reversal invariant if and only if inverted losses are considered in the back-propagation phase. This paper presents an analysis of the impact of losses on the performance of the EMTR-based fault location method for power networks. In this respect, three back-propagation models are proposed, analyzed, and compared. It is shown that a lossy back-propagation model, for which the wave equations are not rigorously time-reversal invariant, results in accurate fault locations. Finally, an EMTR fault location system based on the lossy back-propagation model and a fast electromagnetic transient simulation platform is developed and its performances validated. Autors: Reza Razzaghi;Gaspard Lugrin;Farhad Rachidi;Mario Paolone; Appeared in: IEEE Transactions on Power Delivery Publication date: Oct 2017, volume: 32, issue:5, pages: 2303 - 2312 Publisher: IEEE
» Asynchronous Multirate Multisensor Data Fusion Over Unreliable Measurements With Correlated Noise
 Abstract:In this paper, the problem of optimal state estimation is studied for fusion of asynchronous multirate multiscale sensors with unreliable measurements and correlated noise. The noise of different sensors is cross-correlated and coupled with the system noise of the previous step and the same time step. The system is described at the highest sampling rate with different sensors observing a single target independently with multiple sampling rates. An optimal state estimation algorithm based on iterative estimation of the white noise estimator is presented, which makes full use of the observation information effectively, overcomes the packet loss, data fault, unreliable factors, and improves the precision and the robustness of the system state estimation. A numerical example is used to illustrate the effectiveness of the presented algorithm. Autors: Lu Jiang;Liping Yan;Yuanqing Xia;Qiao Guo;Mengyin Fu;Kunfeng Lu; Appeared in: IEEE Transactions on Aerospace and Electronic Systems Publication date: Oct 2017, volume: 53, issue:5, pages: 2427 - 2437 Publisher: IEEE
» Asynchronous Physical-Layer Network Coding: Symbol Misalignment Estimation and Its Effect on Decoding
 Abstract:In asynchronous physical-layer network coding (APNC) systems, the symbols from multiple transmitters to a common receiver may be misaligned. Knowledge of the amount of symbol misalignment, hence its estimation, is important to PNC decoding. This paper addresses the problems of symbol-misalignment estimation and optimal PNC decoding given the misalignment estimate, assuming the APNC system uses the root-raised-cosine pulse to carry signals (RRC-APNC). Our contributions are as follows. First, we put forth an optimal symbol-misalignment estimator that makes use of double baud-rate samples. Second, we devise optimal RRC-APNC decoders in the presence of non-exact symbol-misalignment estimates. In particular, we show how to whiten the colored noise in the double baud-rate samples to simplify the design of optimal decoders. Third, we investigate the decoding performance of various estimation-and-decoding schemes for RRC-APNC. Extensive simulations show that: 1) our double baud-rate estimator yields substantially more accurate symbol-misalignment estimates than the baud-rate estimator does; the mean square error gains are up to 8 dB and 2) an overall estimation-and-decoding scheme in which both estimation and decoding are based on double baud-rate samples yields much better performance than other schemes. Compared with a scheme in which both estimation and decoding are based on baud-rate samples, the double baud-rate sampling scheme yields 4.5 dB gains on symbol error rate performance in an additive white Gaussian noise channel, and 2 dB gains on packet error rate performance in a Rayleigh fading channel. Autors: Yulin Shao;Soung Chang Liew;Lu Lu; Appeared in: IEEE Transactions on Wireless Communications Publication date: Oct 2017, volume: 16, issue:10, pages: 6881 - 6894 Publisher: IEEE
» Audible Noise Characteristics of Filter Capacitors Used in HVDC Converter Stations
 Abstract:This paper presents a detailed investigation of audible noise characterization of filter capacitors by investigating the noise radiation characteristics and analyzing the effect of voltage frequency, phase angle, and magnitude on a single capacitor unit. First, the noise radiation for capacitor surfaces was characterized theoretically using finite rectangular plate model and experimentally measured in a semianechoic room. Second, voltage frequency impact on the noise distribution was investigated through simulation. The simulation results show that noise directivity increases with increasing frequency. The excitation frequency impact on the radiation ratio and the noise level was characterized through a sweep-frequency experiment. Our investigations show that the noise frequency response below 500 Hz is quite low, while from 500 to 2000 Hz, it is significant and increases slowly. Third, the impact of the voltage phase angle on the noise level was investigated. The results show a noise-level difference of 3.9 dB for different phase angles. Finally, we present the voltage magnitude impact on the noise level. Our theoretical analysis and experimental study show a linear relationship between the sound power level and the logarithm of the voltage magnitude with a slope of 40. Autors: Lingyu Zhu;Jinyu Li;Yuhang Shi;Habibur Rehman;Shengchang Ji; Appeared in: IEEE Transactions on Power Delivery Publication date: Oct 2017, volume: 32, issue:5, pages: 2263 - 2271 Publisher: IEEE
» Augmented Reality Marker Hiding with Texture Deformation
 Abstract:Augmented reality (AR) marker hiding is a technique to visually remove AR markers in a real-time video stream. A conventional approach transforms a background image with a homography matrix calculated on the basis of a camera pose and overlays the transformed image on an AR marker region in a real-time frame, assuming that the AR marker is on a planar surface. However, this approach may cause discontinuities in textures around the boundary between the marker and its surrounding area when the planar surface assumption is not satisfied. This paper proposes a method for AR marker hiding without discontinuities around texture boundaries even under nonplanar background geometry without measuring it. For doing this, our method estimates the dense motion in the marker’s background by analyzing the motion of sparse feature points around it, together with a smooth motion assumption, and deforms the background image according to it. Our experiments demonstrate the effectiveness of the proposed method in various environments with different background geometries and textures. Autors: Norihiko Kawai;Tomokazu Sato;Yuta Nakashima;Naokazu Yokoya; Appeared in: IEEE Transactions on Visualization and Computer Graphics Publication date: Oct 2017, volume: 23, issue:10, pages: 2288 - 2300 Publisher: IEEE
» Automated Classification of Breast Cancer Stroma Maturity From Histological Images
 Abstract:Objective: The tumor microenvironment plays a crucial role in regulating tumor progression by a number of different mechanisms, in particular, the remodeling of collagen fibers in tumor-associated stroma, which has been reported to be related to patient survival. The underlying motivation of this work is that remodeling of collagen fibers gives rise to observable patterns in hematoxylin and eosin (H&E) stained slides from clinical cases of invasive breast carcinoma that the pathologist can label as mature or immature stroma. The aim of this paper is to categorise and automatically classify stromal regions according to their maturity and show that this classification agrees with that of skilled observers, hence providing a repeatable and quantitative measure for prognostic studies. Methods: We use multiscale basic image features and local binary patterns, in combination with a random decision trees classifier for classification of breast cancer stroma regions-of-interest (ROI). Results: We present results from a cohort of 55 patients with analysis of 169 ROI. Our multiscale approach achieved a classification accuracy of 84%. Conclusion: This work demonstrates the ability of texture-based image analysis to differentiate breast cancer stroma maturity in clinically acquired H&E-stained slides at least as well as skilled observers. Autors: Sara Reis;Patrycja Gazinska;John H. Hipwell;Thomy Mertzanidou;Kalnisha Naidoo;Norman Williams;Sarah Pinder;David J. Hawkes; Appeared in: IEEE Transactions on Biomedical Engineering Publication date: Oct 2017, volume: 64, issue:10, pages: 2344 - 2352 Publisher: IEEE
» Automated Detection of Ice and Open Water From Dual-Polarization RADARSAT-2 Images for Data Assimilation
 Abstract:In this paper, we present a new technique for automated detection of ice and open water from RADARSAT-2 ScanSAR dual-polarization HH-HV images. Probability of the presence of ice within 2.05 km km areas is modeled using a form of logistic regression as a function of the difference between the wind speeds estimated from synthetic aperture radar (SAR) data and those obtained from numerical weather prediction short-term forecasts, the spatial correlation between HH and HV backscatter signals, and the spatial standard deviation of the wind speed estimated from SAR. The resulting ice probability model was built based on thousands of SAR images and corresponding Canadian Ice Service (CIS) Image Analysis products covering all seasons and all Canadian and adjacent Arctic regions being monitored by CIS. Extensive verification of the proposed technique was conducted for an entire year (2013) against independent Image Analysis products and Interactive Multisensor Snow and Ice Mapping System ice extent products. Using a probability threshold of 0.95, 72.2% of the retrievals were classified as either ice or open water with an accuracy of 99.2% in the most clean verification scenario against Image Analysis pure ice and water data. The ability to obtain such a large number of retrievals with a very high accuracy makes it feasible to assimilate the resulting retrievals in an ice prediction system. Consequently, the developed ice/water retrieval technique will be implemented as a part of the data assimilation component of the operational Environment and Climate Change Canada Regional Ice-Ocean Prediction System. Autors: Alexander S. Komarov;Mark Buehner; Appeared in: IEEE Transactions on Geoscience and Remote Sensing Publication date: Oct 2017, volume: 55, issue:10, pages: 5755 - 5769 Publisher: IEEE
» Automated Extraction and Clustering of Requirements Glossary Terms
 Abstract:A glossary is an important part of any software requirements document. By making explicit the technical terms in a domain and providing definitions for them, a glossary helps mitigate imprecision and ambiguity. A key step in building a glossary is to decide upon the terms to include in the glossary and to find any related terms. Doing so manually is laborious, particularly for large requirements documents. In this article, we develop an automated approach for extracting candidate glossary terms and their related terms from natural language requirements documents. Our approach differs from existing work on term extraction mainly in that it clusters the extracted terms by relevance, instead of providing a flat list of terms. We provide an automated, mathematically-based procedure for selecting the number of clusters. This procedure makes the underlying clustering algorithm transparent to users, thus alleviating the need for any user-specified parameters. To evaluate our approach, we report on three industrial case studies, as part of which we also examine the perceptions of the involved subject matter experts about the usefulness of our approach. Our evaluation notably suggests that: (1) Over requirements documents, our approach is more accurate than major generic term extraction tools. Specifically, in our case studies, our approach leads to gains of 20 percent or more in terms of recall when compared to existing tools, while at the same time either improving precision or leaving it virtually unchanged. And, (2) the experts involved in our case studies find the clusters generated by our approach useful as an aid for glossary construction. Autors: Chetan Arora;Mehrdad Sabetzadeh;Lionel Briand;Frank Zimmer; Appeared in: IEEE Transactions on Software Engineering Publication date: Oct 2017, volume: 43, issue:10, pages: 918 - 945 Publisher: IEEE
» Automated Transportation of Biological Cells for Multiple Processing Steps in Cell Surgery
 Abstract:Most studies on automated cell transportation are single-task oriented. Results from these investigations hardly meet the increasing demand for emerging cell surgery operations that usually require a series of manipulation tasks with multiple processing steps. In this paper, automated cell transportation to accomplish a multistep process in cell surgery was investigated. A novel control system that can manipulate grouped cells to move into different task regions sequentially and continuously without interruption was developed based on a robot-aided optical tweezers manipulation system. A potential field-based controller was designed to achieve multistep processing control, where the new concepts of contractive coalition and switching region were incorporated into tweezers–cell coalition. The success of this controller lies in simultaneously controlling the positions of the optical tweezers, trapping multiple cells effectively, and avoiding collisions in a unified manner. Simulations and experiments of transferring a group of cells to a number of task regions were performed to demonstrate the effectiveness of the proposed approach. Note to Practitioners—This paper was motivated by the challenging problem of automated transportation of grouped cells to several predefined task regions in emerging cell surgery with multiple processing steps. Existing automated cell transportation studies are mainly single-task oriented, thereby making them inapplicable to cell surgery operations, because a series of sequential processing steps are usually involved in these operations. This paper provides a novel control strategy based on a robot-aided optical tweezers manipulation system to efficiently transport cells into different task regions sequentially without interruption. Unlike the previous cell transportation studies where the goal positions of single cells must be specified early, here only the desired task regions are i- entified in the controller implementation, making the proposed strategy a better fit for actual cell surgery practice. Autors: Hao Yang;Xiangpeng Li;Yunhui Liu;Dong Sun; Appeared in: IEEE Transactions on Automation Science and Engineering Publication date: Oct 2017, volume: 14, issue:4, pages: 1712 - 1721 Publisher: IEEE
» Automatic and Fast PCM Generation for Occluded Object Detection in High-Resolution Remote Sensing Images
 Abstract:Partial configuration model (PCM) is an occluded object detection method in high-resolution remote sensing images (HR-RSIs) based on the deformable part-based model (DPM). However, it needs extra category predefinition, considerable part-level annotation, and repeated multimodel training. In this letter, an automatic and fast PCM generation method is proposed based on a novel part sharing mechanism. We propose to share parts from one trained DPM model (tDPM) among different models of partial configurations (PCs) to address the above problems. PCs are first designed according to part anchors of tDPM. The model is then generated through corresponding parts selection, root coverage cropping, and elements reweighing. This method avoids the need for manual category predefinition and part-level annotation, while largely reducing the computation of PCM training. Experimental results on three HR-RSI data sets show that the proposed method obtains a training speedup of and for each PC of airplane and ship categories, while achieving a comparable accuracy compared with PCM. Autors: Shaohua Qiu;Gongjian Wen;Zhipeng Deng;Yaxiang Fan;Bingwei Hui; Appeared in: IEEE Geoscience and Remote Sensing Letters Publication date: Oct 2017, volume: 14, issue:10, pages: 1730 - 1734 Publisher: IEEE
» Automatic Identification of Weave Patterns of Checked and Colored Fabrics Using Optical Coherence Tomography
 Abstract:Identifying the weave pattern of fabrics can be done manually or automatically. Carrying out the weave recognition automatically will reduce the procedure time and error rates since automatic systems can perform successive measurements at high speeds and with great repeatability and quality. Woven fabric repeat identification systems that are automatic, usually work by employing complex algorithms and techniques. It is known that these automatic techniques struggle when trying to identify highly complex patterns, composing of a combination of different structures, figures, and colors. For example, image processing algorithms are known to make errors when dealing with checked and colored fabrics. In this paper, we apply the spectral domain optical coherence tomography imaging technique for identifying checked and colored woven fabric repeat automatically. This is achieved by employing an in-house written JAVA code that extracts the weave pattern from the tomography images. We show that automatic identification of weave pattern of checked and colored fabrics can be performed nondestructively by employing optical coherence tomography. Autors: Metin Sabuncu;Hakan Ozdemir;Mete U. Akdogan; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 8 Publisher: IEEE
» Automatic MTPA Tracking in IPMSM Drives: Loop Dynamics, Design, and Auto-Tuning
 Abstract:Maximum Torque Per Ampere (MTPA) based on motor parameters is a common approach to achieve high efficiency and torque density in Interior Permanent Magnet Synchronous Machine Drives (IPMSMs). However, uncertainty (e.g., due to identification errors, magnetic saturation, or temperature variation) results in undesired deviation from the optimal operating trajectory. To solve this problem, MTPA tracking methods have been proposed, which exploit signal injection to search the minimum current point for a certain load torque in a closed-loop fashion. Closed-form design of the MTPA tracking loop dynamics has never been addressed in past literature and represents the main topic of this paper. A recent and efficient tracking method has been considered for the analysis and case study, i.e., [14]. Nonlinear small-signal gain of the loop can be calculated in closed form, leading to two valuable results. Dynamics can be programmed by optimal design of the tracking regulator, and online adaptation can be applied, making the designed MTPA tracking dynamics invariant with the operating point. A straightforward and effective solution is proposed for the regulator design, which allows us to obtain the desired bandwidth and first-order tracking response in the whole range of operation, being also suitable for auto-tuning and online adaptation. The method has been studied analytically and in simulation, also considering the influence of noise and parametric uncertainties. Finally the technique has been implemented on the hardware of a commercial industrial drive, proving the effectiveness of the proposal. The concepts described in this paper, design approach and adaptation strategy, analyzed here for the first time, are general and can be applied to any control scheme implementing closed-loop MTPA tracking. Autors: Nicola Bedetti;Sandro Calligaro;Christian Olsen;Roberto Petrella; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4547 - 4558 Publisher: IEEE
» Automatic Nuclear Segmentation Using Multiscale Radial Line Scanning With Dynamic Programming
 Abstract:In the diagnosis of various cancers by analyzing histological images, automatic nuclear segmentation is an important step. However, nuclear segmentation is a difficult problem because of overlapping nuclei, inhomogeneous staining, and presence of noisy pixels and other tissue components. In this paper, we present an automatic technique for nuclear segmentation in skin histological images. The proposed technique first applies a bank of generalized Laplacian of Gaussian kernels to detect nuclear seeds. Based on the detected nuclear seeds, a multiscale radial line scanning method combined with dynamic programming is applied to extract a set of candidate nuclear boundaries. The gradient, intensity, and shape information are then integrated to determine the optimal boundary for each nucleus in the image. Nuclear overlap limitation is finally imposed based on a Dice coefficient measure such that the obtained nuclear contours do not severely intersect with each other. Experiments have been thoroughly performed on two datasets with H&E and Ki-67 stained images, which show that the proposed technique is superior to conventional schemes of nuclear segmentation. Autors: Hongming Xu;Cheng Lu;Richard Berendt;Naresh Jha;Mrinal Mandal; Appeared in: IEEE Transactions on Biomedical Engineering Publication date: Oct 2017, volume: 64, issue:10, pages: 2475 - 2485 Publisher: IEEE
» Automatic Rich Map Semantics Identification Through Smartphone-Based Crowd-Sensing
 Abstract:Digital maps have become a part of our daily lives with a growing number of commercial and free map services. However, these services still have a huge potential for enhancement with rich semantic information to support a large class of mapping applications. In this paper, we present Map++, a system that leverages commodity off-the-shelf smartphones in a crowd-sensing approach to automatically enrich digital maps with different road semantics like tunnels, bumps, bridges, footbridges, crosswalks, road capacity, among others. Our analysis shows that the smartphones sensors, whether with a user riding a vehicle or walking, get affected by the different road features which can be mined to extend the features of both free and commercial mapping services. Map++ leverages these detected features and employs a probabilistic framework that can handle the heterogeneity and uncertainty in the crowd-sensed data to update the digital maps. We present the design and implementation of Map++ and evaluate it in four cities. Our evaluation shows that we can detect different map features accurately with 4 percent false positive and 8 percent false negative rates for in-vehicle traces, and 3 percent false positive and 4 percent false negative rates for pedestrian traces. Moreover, we show that Map++ has a small energy footprint on the cell-phones, highlighting its promise as a ubiquitous digital maps enriching service. Autors: Heba Aly;Anas Basalamah;Moustafa Youssef; Appeared in: IEEE Transactions on Mobile Computing Publication date: Oct 2017, volume: 16, issue:10, pages: 2712 - 2725 Publisher: IEEE
» Automatically Enforcing Security SLAs in the Cloud
 Abstract:Dealing with the provisioning of cloud services granted by Security SLAs is a very challenging research topic. At the state of the art, the main related issues involve: (i) representing security features so that they are understandable by both customers and providers and measurable (by means of verifiable security-related Service Level Objectives (SLOs)), (ii) automating the provisioning of security mechanisms able to grant desired security features (by means of a security-driven resource allocation process), and (iii) continuously monitoring the services in order to verify the fulfillment of specified Security SLOs (by means of cloud security monitoring solutions). We propose to face the Security SLA life cycle management with a framework able to enrich cloud applications with security features. In this paper we (i) present a novel Security SLA model and (ii) illustrate a security-driven planning process that can be adopted to determine the (optimum) deployment of security-related software components. Such process takes into account both specific implementation constraints of the security components to be deployed and customers security requirements, and enables the automatic provisioning and configuration of all needed resources. In order to demonstrate the applicability of the approach, we present and discuss a practical application of the model on a real case study. Autors: Valentina Casola;Alessandra De Benedictis;Mădălina Eraşcu;Jolanda Modic;Massimiliano Rak; Appeared in: IEEE Transactions on Services Computing Publication date: Oct 2017, volume: 10, issue:5, pages: 741 - 755 Publisher: IEEE
» Backstepping Design of Robust State Feedback Regulators for Linear $2 \times 2$ Hyperbolic Systems
 Abstract:This technical note deals with the robust output regulation problem for boundary controlled linear hyperbolic systems. Thereby, the output to be controlled can be located at one of the boundaries or is a pointwise in-domain output. By utilizing the internal model principle, a state feedback regulator is determined for a finite-dimensional signal model describing the exogenous signals. This amounts to stabilizing a hyperbolic PDE-ODE cascade coupled at an intermediate point. For this, a systematic backstepping method is developed to determine the stabilizing state feedback controller. The solvability of the considered output regulation problem can easily be verified on the basis of the nominal plant transfer behaviour. For non-destabilizing model uncertainties the robustness of the achieved output regulation is verified. An uncertain hyperbolic system with an in-domain output illustrates the results of the technical note. Autors: Joachim Deutscher; Appeared in: IEEE Transactions on Automatic Control Publication date: Oct 2017, volume: 62, issue:10, pages: 5240 - 5247 Publisher: IEEE
» Backstepping Fuzzy Adaptive Control for a Class of Quantized Nonlinear Systems
 Abstract:This paper proposes a new adaptive controller for a class of uncertain nonlinear systems with a quantized signal. Fuzzy logic systems are utilized to approximate nonlinear terms without imposing prior matching conditions required. A hysteretic type of quantizer is incorporated to reduce chattering. A new adaptive backstepping controller is designed to guarantee that the underlying uncertain nonlinear system is semiglobally uniformly ultimately bounded. Two numerical examples are presented to demonstrate the effectiveness and potential of the proposed techniques. Autors: Wenhui Liu;Cheng-Chew Lim;Peng Shi;Shengyuan Xu; Appeared in: IEEE Transactions on Fuzzy Systems Publication date: Oct 2017, volume: 25, issue:5, pages: 1090 - 1101 Publisher: IEEE
» Bacterial Relay for Energy-Efficient Molecular Communications
 Abstract:In multi-cellular organisms, molecular signaling spans multiple distance scales and is essential to tissue structure and functionality. Molecular communications is increasingly researched and developed as a key subsystem in the Internet-of-Nano-Things paradigm. While short range microscopic diffusion communications is well understood, longer range channels can be inefficient and unreliable. Static and mobile relays have been proposed in both conventional wireless systems and molecular communication contexts. In this paper, our main contribution is to analyze the information delivery energy efficiency of bacteria mobile relays. We discover that these mobile relays offer superior energy efficiency compared with pure diffusion information transfer over long diffusion distances. This paper has widespread implications ranging from understanding biological processes to designing new efficient synthetic biology communication systems. Autors: Song Qiu;Werner Haselmayr;Bin Li;Chenglin Zhao;Weisi Guo; Appeared in: IEEE Transactions on NanoBioscience Publication date: Oct 2017, volume: 16, issue:7, pages: 555 - 562 Publisher: IEEE
» Balanced Tri-Band Bandpass Filter Design Using Octo-Section Stepped-Impedance Ring Resonator With Open Stubs
 Abstract:A balanced tri-band bandpass filter (BPF) is proposed based on octo-section stepped-impedance ring resonator (SIRR). The relation and design graphs between the differential-mode (DM) and common-mode (CM) characteristics with different physical parameters are analyzed. It reveals that the proposed SIRR has more degrees of freedom in controlling DM and CM characteristics for tri-band design with excellent out-of-band performances and high CM suppression. Moreover, the SIRR is loaded by open stubs with different lengths to further improve the CM suppression. Finally, a balanced tri-band BPF prototype is fabricated and measured. Good agreement between simulated and experimental results verifies this design method. Autors: Haiwen Liu;Yi Song;Baoping Ren;Pin Wen;Xuehui Guan;Hexiu Xu; Appeared in: IEEE Microwave and Wireless Components Letters Publication date: Oct 2017, volume: 27, issue:10, pages: 912 - 914 Publisher: IEEE
» Balancing of Peak Currents Between Paralleled SiC MOSFETs by Drive-Source Resistors and Coupled Power-Source Inductors
 Abstract:The peak currents between two paralleled SiC MOSFETs could differ significantly due to the mismatch in threshold voltages Vth. The method described herein employs passive compensation (drive-source resistors and coupled power-source inductors) to balance the peak currents using one gate driver, no sensors, and no feedback- without increasing total switching loss when equivalent gate-drive resistance (Rg + 0.5Rk) is kept constant. This solution works for both polarities of Vth mismatch and forces balancing from the first current peak. The extra voltage stress from this solution is mitigated by negative coupling. The passive components (resistance, self-inductance, and mutual inductance) are determined by an equation involving the magnitude of Vth mismatch, current rise time, and unbalance percentage. The influence of other parasitic inductances on current sharing is analyzed. The robustness of this passive balancing method is experimentally verified by a prototype with a significant amount of parasitic inductances. Test results show that the difference of peak currents can be reduced from 15% to 3% without changing the switching loss and voltage stress. Autors: Yincan Mao;Zichen Miao;Chi-Ming Wang;Khai D. T. Ngo; Appeared in: IEEE Transactions on Industrial Electronics Publication date: Oct 2017, volume: 64, issue:10, pages: 8334 - 8343 Publisher: IEEE
» Bandwidth Management for Soft Real-Time Control Applications in Industrial Wireless Networks
 Abstract:Industrial distributed control systems would greatly benefit from the adoption of wireless communication technologies, if only guarantees could be provided on timing of time-critical data delivery over the ether. This paper presents solutions to handle single-hop deadline-constrained periodic traffic, which combine centralized transmission scheduling according to earliest deadline first (EDF) and automatic repeat request (ARQ). For each solution, an admission control test is provided, which guarantees a configurable number of retries to each data instance within its deadline, statically addressing both timeliness and reliability on a per-instance basis. Dynamic bandwidth management strategies are also introduced that use runtime information about unperformed guaranteed retries and reassign them, as extra retries, to failed instances whose deadline has not yet expired. Simulation results show that significant benefits can be obtained, in terms of both determinism and improved performance, by a careful static/dynamic management of the available communication resources. Autors: Lucia Seno;Gianluca Cena;Adriano Valenzano;Claudio Zunino; Appeared in: IEEE Transactions on Industrial Informatics Publication date: Oct 2017, volume: 13, issue:5, pages: 2484 - 2495 Publisher: IEEE
» Bandwidth-efficient synchronization for fiber optic transmission: system performance measurements
 Abstract:By any measure, the various services and applications which are crucial to today's society rely on fast, efficient, and reliable information exchange. Nowadays, most of this information traffic is carried over long distances by optical fiber, which has intrinsic advantages such as wide transmission bandwidth and low attenuation. However, continuing traffic growth has imposed many challenges, especially for equipment manufacturers who have to develop optical transmission solutions to handle the demand for higher data rates without incurring increased capital and operational costs. A feasible approach to overcoming these challenges is to scale the channel capacity by employing orthogonal frequency division multiplexing (OFDM) super-channels. However, OFDM is sensitive to synchronization errors, which can result in complete failure of the receiver-based digital signal processing. Measurement results of various existing OFDM synchronization methods have highlighted inherent limitations with regards to poor system performance, which determines the quality-of-service level perceived by the end user, and complexity, which throws doubts as to their suitability for implementation in actual equipment. In this article, we provide a brief overview of optical transmission systems and some of their performance specifications. We then present a simple, robust, and bandwidth-efficient OFDM synchronization method and carry out measurements to validate the presented synchronization method with the aid of an experimental setup. Autors: Oluyemi Omomukuyo;Octavia A. Dobre;Ramachandran Venkatesan;Telex M. N. Ngatched; Appeared in: IEEE Instrumentation & Measurement Magazine Publication date: Oct 2017, volume: 20, issue:5, pages: 39 - 45 Publisher: IEEE
» Barrier Height Variation in Ni-Based AlGaN/GaN Schottky Diodes
 Abstract:In this paper, we have investigated Ni-based AlGaN/GaN Schottky diodes comprising capping layers with silicon-technology-compatible metals such as TiN, TiW, TiWN, and combinations thereof. The observed change in Schottky barrier height of a Ni and Ni/TiW/TiWN/TiW contact can be explained by stress effects induced by the TiW/TiWN/TiW capping layer, rather than by chemical reactions at the metal–semiconductor interface. Secondary-ion mass spectroscopy and transmission electron microscopy techniques, for samples with and without a TiW/TiWN/TiW cap, have been used to show that no chemical reactions take place. In addition, electrical characterization of dedicated samples revealed that the barrier height of Ni/TiW/TiWN/TiW contacts increases after stepwise selective removal of the TiW/TiWN/TiW cap, thus demonstrating the impact of strain. Autors: Marcin Hajłasz;Johan J. T. M. Donkers;Saurabh Pandey;Fred Hurkx;Raymond J. E. Hueting;Dirk J. Gravesteijn; Appeared in: IEEE Transactions on Electron Devices Publication date: Oct 2017, volume: 64, issue:10, pages: 4050 - 4056 Publisher: IEEE
» Bayesian Hyperspectral and Multispectral Image Fusions via Double Matrix Factorization
 Abstract:This paper focuses on fusing hyperspectral and multispectral images with an unknown arbitrary point spread function (PSF). Instead of obtaining the fused image based on the estimation of the PSF, a novel model is proposed without intervention of the PSF under Bayesian framework, in which the fused image is decomposed into double subspace-constrained matrix-factorization-based components and residuals. On the basis of the model, the fusion problem is cast as a minimum mean square error estimator of three factor matrices. Then, to approximate the posterior distribution of the unknowns efficiently, an estimation approach is developed based on variational Bayesian inference. Different from most previous works, the PSF is not required in the proposed model and is not pre-assumed to be spatially invariant. Hence, the proposed approach is not related to the estimation errors of the PSF and has potential computational benefits when extended to spatially variant imaging system. Moreover, model parameters in our approach are less dependent on the input data sets and most of them can be learned automatically without manual intervention. Exhaustive experiments on three data sets verify that our approach shows excellent performance and more robustness to the noise with acceptable computational complexity, compared with other state-of-the-art methods. Autors: Baihong Lin;Xiaoming Tao;Mai Xu;Linhao Dong;Jianhua Lu; Appeared in: IEEE Transactions on Geoscience and Remote Sensing Publication date: Oct 2017, volume: 55, issue:10, pages: 5666 - 5678 Publisher: IEEE
» Bayesian Networks in Fault Diagnosis
 Abstract:Fault diagnosis is useful in helping technicians detect, isolate, and identify faults, and troubleshoot. Bayesian network (BN) is a probabilistic graphical model that effectively deals with various uncertainty problems. This model is increasingly utilized in fault diagnosis. This paper presents bibliographical review on use of BNs in fault diagnosis in the last decades with focus on engineering systems. This work also presents general procedure of fault diagnosis modeling with BNs; processes include BN structure modeling, BN parameter modeling, BN inference, fault identification, validation, and verification. The paper provides series of classification schemes for BNs for fault diagnosis, BNs combined with other techniques, and domain of fault diagnosis with BN. This study finally explores current gaps and challenges and several directions for future research. Autors: Baoping Cai;Lei Huang;Min Xie; Appeared in: IEEE Transactions on Industrial Informatics Publication date: Oct 2017, volume: 13, issue:5, pages: 2227 - 2240 Publisher: IEEE
» BCI Use and Its Relation to Adaptation in Cortical Networks
 Abstract:Brain-computer interfaces (BCIs) carry great potential in the treatment of motor impairments. As a new motor output, BCIs interface with the native motor system, but acquisition of BCI proficiency requires a degree of learning to integrate this new function. In this review, we discuss how BCI designs often take advantage of the brain’s motor system infrastructure as sources of command signals. We highlight a growing body of literature examining how this approach leads to changes in activity across cortex, including beyond motor regions, as a result of learning the new skill of BCI control. We discuss the previous research identifying patterns of neural activity associated with BCI skill acquisition and use that closely resembles those associated with learning traditional native motor tasks. We then discuss recent work in animals probing changes in connectivity of the BCI control site, which were linked to BCI skill acquisition, and use this as a foundation for our original work in humans. We present our novel work showing changes in resting state connectivity across cortex following the BCI learning process. We find substantial, heterogeneous changes in connectivity across regions and frequencies, including interactions that do not involve the BCI control site. We conclude from our review and original work that BCI skill acquisition may potentially lead to significant changes in evoked and resting state connectivity across multiple cortical regions. We recommend that future studies of BCIs look beyond motor regions to fully describe the cortical networks involved and long-term adaptations resulting from BCI skill acquisition. Autors: Kaitlyn Casimo;Kurt E. Weaver;Jeremiah Wander;Jeffrey G. Ojemann; Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering Publication date: Oct 2017, volume: 25, issue:10, pages: 1697 - 1704 Publisher: IEEE
» Beam Diffraction Effects in the Backward Wave Regions of Viscoelastic Leaky Lamb Modes for Plate Transmission at Normal Incidence
 Abstract:Plane-wave theory for fluid-embedded isotropic plates is often used in ultrasonic guided-wave applications, and to estimate wall thickness, corrosion, or sound velocities in plates and pipes. In such structures, measured ultrasonic transmission through the solid material is affected by acoustic beam diffraction effects, and the results may deviate from plane-wave descriptions, which are insufficient to describe the complex effects that occur. When exciting a fluid-embedded steel plate with a pulsed ultrasonic beam at normal incidence, resonance frequency downshift, axial sound pressure level increase, and beam narrowing have been observed, for measured resonance peaks in the frequency regions of certain leaky Lamb mode branches of the plate. In the ranges of other leaky Lamb mode branches, the observed effects are different. Measurements, finite element, and angular spectrum modeling are used to indicate a close connection between these beam diffraction phenomena and the backward wave characteristics of certain leaky Lamb mode pairs, in the frequency and Poisson’s ratio regions around coincidence of two Lamb mode cutoff frequencies of similar symmetry. In particular, such observations made for the steel plate’s fundamental thickness-extensional (TE) mode appear to be caused by acoustic beam excitation of the backward wave regions of the and leaky Lamb modes. Autors: Magne Aanes;Kjetil Daae Lohne;Per Lunde;Magne Vestrheim; Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control Publication date: Oct 2017, volume: 64, issue:10, pages: 1558 - 1572 Publisher: IEEE
» Beam Summation Theory for Waves in Fluctuating Media. Part I: The Beam Frame and the Beam-Domain Scattering Matrix
 Abstract:We present a novel beam summation (BS) formulation for tracking wavefields in fluctuating media. This formulation utilizes the ultrawideband phase-space BS method, which is structured upon a windowed Fourier transform (WFT) frame expansion of the sources and expresses the field as a discrete phase-space sum of beam propagators. This paper extends the frame concept, proving that this beam set constitutes a frame not only in the source domain, where it reduces to the conventional WFT, but everywhere in the propagation domain. This “beam frame” provides a self-consistent framework for tracking wavefields through scattering media in which the local interaction of the incident beams with the medium is expanded using the same set of beams. The resulting beam-to-beam (B2B) scattering coefficients depend on the local spectral properties of the medium. The overall B2B scattering matrix is therefore compact, coupling only beams that are adjacent in phase space, given the fluctuation properties. The new formulation expresses the entire scattering problem in terms of coefficients dynamics in the phase space. As demonstrated, the formulation is computationally efficient and captures all the relevant phenomenology. Part II extends this formulation for stochastic fields in random fluctuating medium characterized by the medium statistics. Autors: Matan Leibovich;Ehud Heyman; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 5431 - 5442 Publisher: IEEE
» Beam–Wave Interaction From FEL to CARM and Associated Scaling Laws
 Abstract:The development of a microwave tube providing high output power (~1 MW) at a high frequency (~250 GHz) with high efficiency of the beam–wave power conversion is a challenging task. A great deal of theoretical and experimental efforts is directed toward such a goal. A promising powerful source of microwave radiation is the cyclotron autoresonance maser (CARM) oscillator. In this paper, we revisit the well-known physical models in a way, which is suitable for their implementation in the numerical tools for computer-aided design and optimization of a CARM operating at high frequency. The analysis developed by us is an attempt directed toward the realization of an adequate design tool for the development of CARM devices. Autors: Emanuele Di Palma;Giuseppe Dattoli;Elio Sabia;Svilen Sabchevski;Ivan Spassovsky; Appeared in: IEEE Transactions on Electron Devices Publication date: Oct 2017, volume: 64, issue:10, pages: 4279 - 4286 Publisher: IEEE
» Beam-Domain Full-Duplex Massive MIMO: Realizing Co-time Co-frequency Uplink and Downlink Transmission in the Cellular System
 Abstract:Co-time co-frequency uplink and downlink (CCUD) transmission was considered challenging in the cellular system due to the strong self-interference (SI) between the transmitter and receiver of base station (BS). In this paper, by investigating the beam-domain representation of channels based on the basis expansion model, we propose a beam-domain full-duplex (BDFD) massive multiple-input multiple-output (MIMO) scheme to make the CCUD transmission possible. The key idea of the BDFD scheme lies in intelligently scheduling the uplink and downlink user equipment (UE) based on the beam-domain distributions of their associated channels to mitigate SI and enhance transmission efficiency. We show that the BDFD scheme achieves significant savings in uplink/downlink training resource and achieves uplink and downlink sum capacities simultaneously as the number of BS antennas approaches infinity. The superiority of the BDFD scheme over the traditional time-division duplex (TDD)/frequency-division duplex (FDD) massive MIMO is evaluated through simulation for the macrocell environment. The results show that the spectral efficiency gain can even exceed 2 in the specific scenarios, since the BDFD scheme utilizes the time-frequency resource more efficiently in both the training and data transmission phases. Autors: Xiaochen Xia;Kui Xu;Dongmei Zhang;Youyun Xu;Yurong Wang; Appeared in: IEEE Transactions on Vehicular Technology Publication date: Oct 2017, volume: 66, issue:10, pages: 8845 - 8862 Publisher: IEEE
» Beamforming in Traffic-Aware Two-Way Relay Systems With Channel Estimation Error and Feedback Delay
 Abstract:This paper presents a comprehensive performance analysis of a multi-antenna-based traffic-aware two-way relay system with unavoidable imperfections in channel state information (CSI) under Nakagami-m fading. Herein, we employ transmit/receive beamforming at source nodes and analog network coding (ANC) at the relay node in the presence of CSI imperfections due to channel estimation errors (CEE) and feedback delay. With such a practical setup, we first deduce the pertinent instantaneous end-to-end signal-to-noise ratios (SNRs) after performing partial self-interference cancellation. Then, by imposing asymmetric traffic requirements in two opposite directions, we conduct an accurate analysis of overall outage probability (OOP) of the considered system. We further derive a tight lower bound on OOP that has a simple and compact closed-form representation. Moreover, based on the asymptotic OOP expression at high SNR, we examine the achievable diversity order of the system. In addition, we acquire an upper bound expression of ergodic sum-rate (ESR) and simplify it further in useful compact form for high SNR regime. Besides, we investigate the optimization problems of relay position to minimize the OOP and to maximize the ESR. Numerical and simulation results validate our theoretical analysis and highlight the impact of CEE and feedback delay under various traffic patterns on the overall system performance. Autors: Devendra Singh Gurjar;Prabhat Kumar Upadhyay;Daniel Benevides da Costa;Rafael Timóteo de Sousa; Appeared in: IEEE Transactions on Vehicular Technology Publication date: Oct 2017, volume: 66, issue:10, pages: 8807 - 8820 Publisher: IEEE
» Behavior Based Human Authentication on Touch Screen Devices Using Gestures and Signatures
 Abstract:With the rich functionalities and enhanced computing capabilities available on mobile computing devices with touch screens, users not only store sensitive information (such as credit card numbers) but also use privacy sensitive applications (such as online banking) on these devices, which make them hot targets for hackers and thieves. To protect private information, such devices typically lock themselves after a few minutes of inactivity and prompt a password/PIN/pattern screen when reactivated. Passwords/ PINs/patterns based schemes are inherently vulnerable to shoulder surfing attacks and smudge attacks. In this paper, we propose BEAT, an authentication scheme for touch screen devices that authenticates users based on their behavior of performing certain actions on the touch screens. An action is either a gesture, which is a brief interaction of a user's fingers with the touch screen such as swipe rightwards, or a signature, which is the conventional unique handwritten depiction of one's name. Unlike existing authentication schemes for touch screen devices, which use what user inputs as the authentication secret, BEAT authenticates users mainly based on howthey input, using distinguishing features such as velocity, device acceleration, and stroke time. Even if attackers see what action a user performs, they cannot reproduce the behavior of the user doing those actions through shoulder surfing or smudge attacks. We implemented BEATon Samsung Focus smart phones and Samsung Slate tablets running Windows, collected 15,009 gesture samples and 10,054 signature samples, and conducted real-time experiments to evaluate its performance. Experimental results show that, with only 25 training samples, for gestures, BEATachieves an average equal error rate of 0.5 percent with three gestures and for signatures, it achieves an average equal error rate of 0.52 percent with single signature. Autors: Muhammad Shahzad;Alex X. Liu;Arjmand Samuel; Appeared in: IEEE Transactions on Mobile Computing Publication date: Oct 2017, volume: 16, issue:10, pages: 2726 - 2741 Publisher: IEEE
» Behavior Recognition Based on Wi-Fi CSI: Part 1
 Abstract:The articles in this special feature provides address behavior recognition based on Wi-Fi channel state estimation (CSI). Human behavior recognition is the core technology that enables a wide variety of human-machine systems and applications (e.g., healthcare, smart homes, and fitness tracking). Traditional approaches mainly use cameras, radars, or wearable sensors. However, all these approaches have certain disadvantages. Examines both the benefits and drawbacks of these technologies and reports on new areas of development for the future. Autors: Bin Guo;Yingying Jennifer Chen;Nic Lane;Yunxin Liu;Zhiwen Yu; Appeared in: IEEE Communications Magazine Publication date: Oct 2017, volume: 55, issue:10, pages: 90 - 90 Publisher: IEEE
» Benefiting From Kinematic Redundancy Alongside Mono- and Biarticular Parallel Compliances for Energy Efficiency in Cyclic Tasks
 Abstract:In this paper, we answer two interleaved questions. The first one is, having a redundant serial manipulator with a given cyclic task, how can we benefit simultaneously from both natural dynamics modification (NDM) and kinematic redundancy resolution to reduce the actuators’ torque? Here, the NDM is done by devising parallel nonlinear monoarticular compliances (MACs), which span one joint, and nonlinear biarticular compliances (BACs), which pass over two joints. We take advantage of kinematic redundancy to exploit the robot's natural dynamics. The second question is how do kinematic redundancy resolution and the NDM interact to minimize the cost? To answer these questions, we cast the problem of simultaneous modification and exploitation of natural dynamics into a constrained multiobjective optimization problem. We show that the set of optimal compliances has an analytical solution as a parametric function of joint trajectories. Accordingly, we study how the components of cost function affect the profile of optimal compliant elements. The proposed method is implemented on a simulated planar 3-DoF manipulator and a simulated nonplanar 4-DoF manipulator for three different tasks. The results shed light on how kinematic redundancy resolution influences efficiency of using MACs and BACs and, consequently, increases attainable gains from the NDM. Moreover, analysis of the results specifies the roles of mono- and BACs and especially explains the reason behind the particular importance of having BACs to reduce the actuation cost. Autors: Hamed Jalaly Bidgoly;Atoosa Parsa;Mohammad Javad Yazdanpanah;Majid Nili Ahmadabadi; Appeared in: IEEE Transactions on Robotics Publication date: Oct 2017, volume: 33, issue:5, pages: 1088 - 1102 Publisher: IEEE
» Beyond Trace Ratio: Weighted Harmonic Mean of Trace Ratios for Multiclass Discriminant Analysis
 Abstract:Linear discriminant analysis (LDA) is one of the most important supervised linear dimensional reduction techniques which seeks to learn low-dimensional representation from the original high-dimensional feature space through a transformation matrix, while preserving the discriminative information via maximizing the between-class scatter matrix and minimizing the within class scatter matrix. However, the conventional LDA is formulated to maximize the arithmetic mean of trace ratios which suffers from the domination of the largest objectives and might deteriorate the recognition accuracy in practical applications with a large number of classes. In this paper, we propose a new criterion to maximize the weighted harmonic mean of trace ratios, which effectively avoid the domination problem while did not raise any difficulties in the formulation. An efficient algorithm is exploited to solve the proposed challenging problems with fast convergence, which might always find the globally optimal solution just using eigenvalue decomposition in each iteration. Finally, we conduct extensive experiments to illustrate the effectiveness and superiority of our method over both of synthetic datasets and real-life datasets for various tasks, including face recognition, human motion recognition and head pose recognition. The experimental results indicate that our algorithm consistently outperforms other compared methods on all of the datasets. Autors: Zhihui Li;Feiping Nie;Xiaojun Chang;Yi Yang; Appeared in: IEEE Transactions on Knowledge and Data Engineering Publication date: Oct 2017, volume: 29, issue:10, pages: 2100 - 2110 Publisher: IEEE
» Biased Run-Length Coding of Bilevel Classification Label Maps of Hyperspectral Images
 Abstract:For efficient coding of bilevel sources with some dominant symbols often found in classification label maps of hyperspectral images, we proposed a novel biased run-length (BRL) coding method, which codes the most probable symbols separately from other symbols. To determine the conditions in which the BRL coding method would be effective, we conducted an analysis of the method using statistical models. We first analyzed the effect of 2-D blocking of pixels, which were assumed to have generalized Gaussian distributions. The analysis showed that the resulting symbol blocks tended to have lower entropies than the original source without symbol blocking. We then analyzed the BRL coding method applied on the sequence of block symbols characterized by a first-order Markov model. Information-theoretic analysis showed that the BRL coding method tended to generate codewords that have lower entropies than the conventional run-length coding method. Furthermore, numerical simulations on lossless compression of actual data showed improvement of the state of the art. Specifically, end-to-end implementation integrating symbol blocking, BRL, and Huffman coding achieved up to 4.3% higher compression than the JBIG2 standard method and up to 3.2% higher compression than the conventional run-length coding method on classification label maps of the widely used “Indian Pines” dataset. Autors: Amir Leon Liaghati;W. David Pan;Zhuocheng Jiang; Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Publication date: Oct 2017, volume: 10, issue:10, pages: 4580 - 4588 Publisher: IEEE
» Bidirectional Polarized Reflectance Factors of Vegetation Covers: Influence on the BRF Models Results
 Abstract:In this paper, we performed multiangular measurements spanning a wide viewing range in a hemisphere space for three types of vegetation cover and analyzed the bidirectional reflectance factor (BRF) measurements based on basic physical reflectance mechanisms to ensure the accuracy of the data. The measurements and the results with the best fitted model parameters were evaluated to determine whether the BRF models produce vegetation cover reflectance factor values that are qualitatively the same as the measured values. These models effectively characterized the BRF of the vegetation cover at most of the selected wavelengths (565, 670, and 865 nm). However, for planophile vegetation cover with smooth leaves, the current BRF models did not produce accurate values in the selected visible wavelength range; the average relative difference was approximately 0.3 at 670 nm. Subsequently, we subtracted the specular reflectance factor (calculated using the bidirectional polarized reflectance factors) from the total BRF and compared these data with the modeled results. The difference between the measured and modeled BRFs was notably decreased when we separated the specular reflectance factor at 670 nm for the planophile vegetation cover with smooth leaves. Moreover, there was a different degree of improvement in the agreement between the measured and modeled results, which depended on the wavelength and the type of vegetation cover. These results indicated that the subtraction of the specular reflectance factor effectively improved the capability of the BRF models to calculate the diffuse portion of the BRF of the vegetation cover. Autors: Zhongqiu Sun;Di Wu;Yunfeng Lv;Yunsheng Zhao; Appeared in: IEEE Transactions on Geoscience and Remote Sensing Publication date: Oct 2017, volume: 55, issue:10, pages: 5687 - 5701 Publisher: IEEE
» Big data at work: the practitioners' point of view
 Abstract:Big Data is one of the many hyper-hyped topics on which the Information Technology industry feeds itself. One can track its origins to visionary and provocative works such as the famous 2008 The End of Theory paper by Chris Anderson, in which the author argues that large enough amounts of data can effectively dilute and finally eliminate the conceptual difference between correlation and causation, favoring the former and rendering substantially useless the research of the latter [1]. More recently, less ambitious and more pragmatic approaches have been proposed, mostly elaborating on the 3-V model originally introduced by Gartner in 2012 [2]. According to this newer perspective, Big Data is about management of data involving combinations of Volumes, Velocity, and Variety that transcend the levels traditionally addressed by IT. A fourth V was later added, bringing in the additional important element of Veracity. Autors: Francesco Mari;Paolo Masini; Appeared in: IEEE Instrumentation & Measurement Magazine Publication date: Oct 2017, volume: 20, issue:5, pages: 13 - 20 Publisher: IEEE
» Big data in I&M [Editorial]
 Abstract:Who could have imagined in the year 1950, when the first mainframes were introduced and data was stored on paper cards, that now we would each have our own personal computer with several gigabytes of memory storage? Autors: Wendy Van Moer; Appeared in: IEEE Instrumentation & Measurement Magazine Publication date: Oct 2017, volume: 20, issue:5, pages: 2 - 2 Publisher: IEEE
» Big Data in Instrumentation and Measurement [Guest Editorial]
 Abstract:The recent rapid growth of information-gathering technologies—from health tracking sensors to smartphones and satellites—produce massive amounts of data from the real world. Similarly, a huge amount of data is steadily collected from the cyber world as a result of internet technologies. In such a context, the “Big Data” phenomenon is expected to have a dramatic impact on society. Indeed, evidence resulting from Big Data is going to support decisions that have the potential to solve big societal problems, boost billion dollar businesses or simply make our everyday lives easier. However, ensuring and understanding the quality of data is crucial to achieve these goals. On one hand, metrology— a science of information quality—is at the very heart of data science. On the other hand, data science could open a new era for measurement science. Autors: Dario Petri; Appeared in: IEEE Instrumentation & Measurement Magazine Publication date: Oct 2017, volume: 20, issue:5, pages: 3 - 3 Publisher: IEEE
» Big data or big (privacy) problem?
 Abstract:Nowadays, almost all of us transfer data (especially personal data) to someone or something (usually through web pages), and we do not precisely know how those data are managed. All of those data, considered altogether, represent what is generally called “Big Data.” Autors: Veronica Scotti; Appeared in: IEEE Instrumentation & Measurement Magazine Publication date: Oct 2017, volume: 20, issue:5, pages: 23 - 26 Publisher: IEEE
» Binary Frequency Shift Keying for Continuous Waveform Radar
 Abstract:A new binary frequency-shift keying (BFSK) waveform is suggested for continuous wave radar. It provides ideal periodic autocorrelation (PAC) when processed by a matched filter, and perfect periodic cross-correlation (PCC) when processed by a mismatched filter. Ideal PAC implies a uniform sidelobe level, whose ratio to the PAC peak is equal to the inverse of the code length. Perfect PCC implies zero sidelobes. BFSK is relatively spectrum efficient. Design details and processing issues are discussed. Autors: Nadav Levanon;Itzik Izchak Cohen; Appeared in: IEEE Transactions on Aerospace and Electronic Systems Publication date: Oct 2017, volume: 53, issue:5, pages: 2462 - 2468 Publisher: IEEE
» Bioinspired Control of Walking With Toe-Off, Heel-Strike, and Disturbance Rejection for a Biped Robot
 Abstract:Human-like features, like toe-off, heel-strike, and disturbance rejection, can enhance the performance of bipedal robots. However, the required control strategies for these motions influence each other, and few studies have considered them simultaneously. Humans can walk stably with toe-off and heel-strike even after experiencing disturbances. Thus, we can study human control strategies, and then, apply them to a bipedal robot. This paper proposes a bioinspired control method to realize stable walking with toe-off and heel-strike for a bipedal robot even after disturbances. First, we analyze human walking and obtain some control strategies. Then, we propose a pattern generator and a walking controller to mimic these strategies. The pattern generator can predefine the zero-moment-point to plan the center of mass trajectory and determine appropriate foot placement. The controller adjusts torso acceleration to make the support leg compliant with the external disturbances. The controller also achieves toe-off and heel-strike in cooperation with the pattern generator. Finally, the validity of the proposed method is confirmed through simulations and experiments. Autors: Xuechao Chen;Zhangguo Yu;Weimin Zhang;Yu Zheng;Qiang Huang;Aiguo Ming; Appeared in: IEEE Transactions on Industrial Electronics Publication date: Oct 2017, volume: 64, issue:10, pages: 7962 - 7971 Publisher: IEEE
» Biomechanical Design of a Novel Flexible Exoskeleton for Lower Extremities
 Abstract:This paper presents a novel wearable walking assistance device for the elderly to provide physical gait assistance. The wearable device, to be worn invisibly underneath clothes, not only fits tightly to the wearer's lower body, but also comfortably transmits assistive torque to the wearer's hip/knee joint. To overcome deficiencies in the usability of conventional wearable walking assistance devices, two novel features are proposed: 1) a unique flexible support frame that withstands vertical loads while maintaining the natural curvature of the wearer's lower body; and 2) a kinematically similar anthropomorphic joint that minimizes the unintended resistance force during the wearer's usual motions. The developed wearable walking assistance device based on these features was verified by simulations and experiments whose results are described. Autors: Younbaek Lee;Yong-Jae Kim;Jongwon Lee;Minhyung Lee;Byungjune Choi;Jeonghun Kim;Young Jin Park;Jungyun Choi; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 2058 - 2069 Publisher: IEEE
» Birefringence Variation Independent Fiber-Optic Current Sensor Using Real-Time SOP Measurement
 Abstract:We propose a birefringence variation independent fiber-optic current sensor based on polarization diversity and a real-time state of polarization measurement technique. We theoretically and experimentally demonstrate the compensation for the degradation of Faraday effect due to the variation in birefringence of the sensing fiber. In experiment, a maximally two times higher sensitivity was achieved compared with that of the conventional one. We investigated temperature dependence of proposed method and the observed maximal variation in sensitivity is as small as 6%. The proposed method exhibits good immunity to the random variation of birefringence and the real rotation angle due to the Faraday effect can be accurately detected. Autors: Yinping Liu;Lin Ma;Zuyuan He; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 9 Publisher: IEEE
» Black-Box Phase Error Compensation for Digital Phase-Shifting Profilometry
 Abstract:Due to the nonlinear response of digital phase-shifting profilometry (PSP), phase errors are inevitable in the retrieved 3-D profiles and result in negative impacts on the measurement accuracy of the PSP system. A novel method is presented in this paper to reduce the impact. Instead of compensating phase errors in the retrieved 3-D profile, specific harmonics are superimposed upon the initial fringe pattern actively to adjust the amplitudes of the harmonics in the captured fringe image with the intention to suppress the phase error, and all nonlinear response of the PSP system can be compensated in theory. Furthermore, it does not consume additional time in the 3-D profile reconstruction process. Experimental results are shown to demonstrate the validity of the method. Autors: Wei Zhang;Liandong Yu;Weishi Li;Haojie Xia;Huaxia Deng;Jin Zhang; Appeared in: IEEE Transactions on Instrumentation and Measurement Publication date: Oct 2017, volume: 66, issue:10, pages: 2755 - 2761 Publisher: IEEE
» Blind Quality Assessment of Fused WorldView-3 Images by Using the Combinations of Pansharpening and Hypersharpening Paradigms
 Abstract:WorldView 3 (WV-3) is the first commercially deployed super-spectral, very high-resolution (HR) satellite. However, the resolution of the short-wave infrared (SWIR) bands is much lower than that of the other bands. In this letter, we describe four different approaches, which are combinations of pansharpening and hypersharpening methods, to generate HR SWIR images. Since there are no ground truth HR SWIR images, we also propose a new picture quality predictor to assess hypersharpening performance, without the need for reference images. We describe extensive experiments using actual WV-3 images that demonstrate that some approaches can yield better performance than others, as measured by the proposed blind image quality assessment model of hypersharpened SWIR images. Autors: Chiman Kwan;Bence Budavari;Alan C. Bovik;Giovanni Marchisio; Appeared in: IEEE Geoscience and Remote Sensing Letters Publication date: Oct 2017, volume: 14, issue:10, pages: 1835 - 1839 Publisher: IEEE
» Block Distributed Compressive Sensing-Based Doubly Selective Channel Estimation and Pilot Design for Large-Scale MIMO Systems
 Abstract:The doubly selective (DS) channel estimation in the large-scale multiple-input multiple-output (MIMO) systems is a challenging problem due to the large number of the channel coefficients to be estimated, which requires unaffordable and prohibitive pilot overhead. In this paper, first we conduct the analysis about the common sparsity of the basis expansion model (BEM) coefficients among all the BEM orders and all the transmit–receive antenna pairs. Then, a novel pilot pattern is proposed, which inserts the guard pilots to deal with the intercarrier interference under the superimposed pilot pattern. Moreover, by exploiting the common sparsity of the BEM coefficients among different BEM orders and different antennas, we propose a block distributed compressive sensing-based DS channel estimator for the large-scale MIMO systems. Its structured sparsity leads to the reduction of the pilot overhead under the premise of guaranteeing the accuracy of the estimation. Furthermore, taking consideration of the block structure, a pilot design algorithm referred to as block discrete stochastic optimization is proposed. It optimizes the pilot positions by reducing the coherence among different blocks of the measurement matrix. Besides, a linear smoothing method is extended to large-scale MIMO systems to improve the accuracy of the estimation. Simulation results verify the performance gains of our proposed estimator and the pilot design algorithm compared with the existing schemes. Autors: Bo Gong;Lin Gui;Qibo Qin;Xiang Ren;Wen Chen; Appeared in: IEEE Transactions on Vehicular Technology Publication date: Oct 2017, volume: 66, issue:10, pages: 9149 - 9161 Publisher: IEEE
» Block Sparse Bayesian Learning-Based NB-IoT Interference Elimination in LTE-Advanced Systems
 Abstract:Narrowband Internet-of-Things (NB-IoT) is one of the emerging 5G technologies, but might introduce narrowband interference (NBI) to existing broadband systems, such as long-term evolution advanced (LTE-A) systems. Thus, the mitigation of the NB-IoT interference to LTE-A is an important issue for the harmonic coexistence and compatibility between 4G and 5G. In this paper, a newly emerged sparse approximation technique, block sparse Bayesian learning (BSBL), is utilized to estimate the NB-IoT interference in LTE-A systems. The block sparse representation of the NBI is constituted through the proposed temporal differential measuring approach, and the BSBL theory is utilized to recover the practical block sparse NBI. A BSBL-based method, partition estimated BSBL, is proposed. With the aid of the estimated block partition beforehand, the Bayesian parameters are obtained to yield the NBI estimation. The intra-block correlation (IBC) is considered to facilitate the recovery. Moreover, exploiting the inherent structure of the identical IBC matrix, another method of informative BSBL is proposed to further improve the accuracy, which does not require prior estimation of the block partition. Reported simulation results demonstrate that the proposed methods are effective in canceling the NB-IoT interference in LTE-A systems, and significantly outperform other conventional methods. Autors: Sicong Liu;Fang Yang;Jian Song;Zhu Han; Appeared in: IEEE Transactions on Communications Publication date: Oct 2017, volume: 65, issue:10, pages: 4559 - 4571 Publisher: IEEE
» Blockchain world - Do you need a blockchain? This chart will tell you if the technology can solve your problem
 Abstract:According to a study released this July by Juniper Research, more than half the world's largest companies are now researching blockchain technologies with the goal of integrating them into their products. Projects are already under way that will disrupt the management of health care records, property titles, supply chains, and even our online identities. But before we remount the entire digital ecosystem on blockchain technology, it would be wise to take stock of what makes the approach unique and what costs are associated with it. Blockchain technology is, in essence, a novel way to manage data. As such, it competes with the data-management systems we already have. Relational databases, which orient information in updatable tables of columns and rows, are the technical foundation of many services we use today. Decades of market exposure and well-funded research by companies like Oracle Corp. have expanded the functionality and hardened the security of relational databases. However, they suffer from one major constraint: They put the task of storing and updating entries in the hands of one or a few entities, whom you have to trust won't mess with the data or get hacked. Autors: Morgen E. Peck; Appeared in: IEEE Spectrum Publication date: Oct 2017, volume: 54, issue:10, pages: 38 - 60 Publisher: IEEE
» Blockchain world - Feeding the blockchain beast if bitcoin ever does go mainstream, the electricity needed to sustain it will be enormous
 Abstract:Bitcoin "miners" are electromagnetic alchemists, effectively turning megawatt-hours of electricity into the world's fastest-growing currency. Their intensive computational activity cryptographically secures the virtual currency, approves transactions, and, in the process, creates new bitcoins for the miners, as payment. And it does another thing, too: It uses an absolutely stunning amount of power. The ever-expanding racks of processors used by miners already consume as much electricity as a small city. It's a problem that experts say is bad and getting worse. "The concern that people continue to debate is, where does this end?" says Michael Reed, head of blockchain technology for Intel. The Bitcoin leech sucking on the world's power grids has been held in check, so far, by rapid gains in the energy efficiency of mining hardware. But energy and blockchain analysts are worried about the possibility of a perfect storm: Those efficiency gains are slowing while bitcoin value is rising fast-and its potential transaction growth is immense. Autors: Peter Fairley; Appeared in: IEEE Spectrum Publication date: Oct 2017, volume: 54, issue:10, pages: 36 - 59 Publisher: IEEE
» Blockchains: How they work and why they'll change the world
 Abstract:Bitcoin was hatched as an act of defiance. Unleashed in the wake of the Great Recession, the cryptocurrency was touted by its early champions as an antidote to the inequities and corruption of the traditional financial system. They cherished the belief that as this parallel currency took off, it would compete with and ultimately dismantle the institutions that had brought about the crisis. Bitcoin's unofficial catchphrase, "In cryptography we trust," left no doubt about who was to blame: It was the middlemen, the bankers, the "trusted" third parties who actually couldn't be trusted. These humans simply got in the way of other humans, skimming profits and complicating transactions. Autors: Morgen E. Peck; Appeared in: IEEE Spectrum Publication date: Oct 2017, volume: 54, issue:10, pages: 26 - 35 Publisher: IEEE
» Book Reviews [7 Reviews]
 Abstract:The following books are reviewed: Computational Intelligence Applications in Smart Grids by A.F. Zobaa and A. Vaccaro; Tailoring of Nanocomposite Dielectrics by T. Tanaka and A.S. Vaughan; Smart Microgrids-Lessons from Campus Microgrid Design and Implementation by H. Farhangi; Principles and Applications of Ubiquitous Sensing by W. Dargie; Understanding Symmetrical Components for Power System Modeling by J.C. Das; Internet of Things and Data Analytics Handbook by H. Geng; Physics of Digital Photography by A. Rowlands Autors: John J. Shea; Appeared in: IEEE Electrical Insulation Magazine Publication date: Oct 2017, volume: 33, issue:5, pages: 56 - 59 Publisher: IEEE
» Boosting the Accuracy of Multispectral Image Pansharpening by Learning a Deep Residual Network
 Abstract:In the field of multispectral (MS) and panchromatic image fusion (pansharpening), the impressive effectiveness of deep neural networks has recently been employed to overcome the drawbacks of the traditional linear models and boost the fusion accuracy. However, the existing methods are mainly based on simple and flat networks with relatively shallow architectures, which severely limits their performance. In this letter, the concept of residual learning is introduced to form a very deep convolutional neural network to make the full use of the high nonlinearity of the deep learning models. Through both quantitative and visual assessments on a large number of high-quality MS images from various sources, it is confirmed that the proposed model is superior to all the mainstream algorithms included in the comparison, and achieves the highest spatial–spectral unified accuracy. Autors: Yancong Wei;Qiangqiang Yuan;Huanfeng Shen;Liangpei Zhang; Appeared in: IEEE Geoscience and Remote Sensing Letters Publication date: Oct 2017, volume: 14, issue:10, pages: 1795 - 1799 Publisher: IEEE
» Boundary Vibration Control of Variable Length Crane Systems in Two-Dimensional Space With Output Constraints
 Abstract:A variable length crane system under the external disturbances and constraints is studied in the two-dimensional space. The dynamical analysis of the cable system considers the variable length, variable tension, variable speed, and the coupled vibrations of the cable in longitudinal-transverse directions. Considering output constraint problems, boundary control algorithms with output signal barriers are designed and acted on the boundary of the cable to reduce the coupled vibrations of the flexible crane cable, and to ensure the stability of the system in theory. Effectiveness and performance of the proposed control schemes are depicted via several simulation examples. Autors: Xiuyu He;Wei He;Jing Shi;Changyin Sun; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 1952 - 1962 Publisher: IEEE
» Brain–Machine Interface Control Algorithms
 Abstract:Motor brain–machine interfaces (BMI) allow subjects to control external devices by modulating their neural activity. BMIs record the neural activity, use a mathematical algorithm to estimate the subject’s intended movement, actuate an external device, and provide visual feedback of the generated movement to the subject. A critical component of a BMI system is the control algorithm, termed decoder. Significant progress has been made in the design of BMI decoders in recent years resulting in proficient control in non-human primates and humans. In this review article, we discuss the decoding algorithms developed in the BMI field, with particular focus on recent designs that are informed by closed-loop control ideas. A motor BMI can be modeled as a closed-loop control system, where the controller is the brain, the plant is the prosthetic, the feedback is the biofeedback, and the control command is the neural activity. Additionally, compared to other closed-loop systems, BMIs have various unique properties. Neural activity is noisy and stochastic, and often consists of a sequence of spike trains. Neural representations of movement could be non-stationary and change over time, for example as a result of learning. We review recent decoder designs that take these unique properties into account. We also discuss the opportunities that exist at the interface of control theory, statistical inference, and neuroscience to devise a control-theoretic framework for BMI design and help develop the next-generation BMI control algorithms. Autors: Maryam M. Shanechi; Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering Publication date: Oct 2017, volume: 25, issue:10, pages: 1725 - 1734 Publisher: IEEE
» BRAIN: A Low-Power Deep Search Engine for Autonomous Robots
 Abstract:Autonomous robots are actively studied for many unmanned applications, however, the heavy computational costs and limited battery capacity make it difficult to implement intelligent decision making in robots. In this article, the authors propose a low-power deep search engine (code-named “BRAIN”) for real-time path planning of intelligent autonomous robots. To achieve low power consumption while maintaining high performance, BRAIN adopts a multithreaded core architecture with a transposition table cache to detect and avoid duplicated searches between the processors at the deeper level of the search tree. In addition, dynamic voltage and frequency scaling is adopted to minimize power consumption without any loss of performance because the workload is gradually decreasing while approaching the target position. BRAIN achieves fast search speed (470,000 searches per second) and low energy consumption (79 nJ per search), and it is successfully applied to the robots for autonomous navigation without any collision in dynamic environments. Autors: Youchang Kim;Dongjoo Shin;Jinsu Lee;Hoi-Jun Yoo; Appeared in: IEEE Micro Publication date: Oct 2017, volume: 37, issue:5, pages: 11 - 19 Publisher: IEEE
» Bridging the Gap Between OpenMP and Task-Based Runtime Systems for the Fast Multipole Method
 Abstract:With the advent of complex modern architectures, the low-level paradigms long considered sufficient to build High Performance Computing (HPC) numerical codes have met their limits. Achieving efficiency, ensuring portability, while preserving programming tractability on such hardware prompted the HPC community to design new, higher level paradigms while relying on runtime systems to maintain performance. However, the common weakness of these projects is to deeply tie applications to specific expert-only runtime system APIs. The OpenMP specification, which aims at providing common parallel programming means for shared-memory platforms, appears as a good candidate to address this issue thanks to the latest task-based constructs introduced in its revision 4.0. The goal of this paper is to assess the effectiveness and limits of this support for designing a high-performance numerical library, ScalFMM, implementing the fast multipole method (FMM) that we have deeply re-designed with respect to the most advanced features provided by OpenMP 4. We show that OpenMP 4 allows for significant performance improvements over previous OpenMP revisions on recent multicore processors and that extensions to the 4.0 standard allow for strongly improving the performance, bridging the gap with the very high performance that was so far reserved to expert-only runtime system APIs. Autors: Emmanuel Agullo;Olivier Aumage;Berenger Bramas;Olivier Coulaud;Samuel Pitoiset; Appeared in: IEEE Transactions on Parallel and Distributed Systems Publication date: Oct 2017, volume: 28, issue:10, pages: 2794 - 2807 Publisher: IEEE
» Bridging the Gap Between Ultrapure Water and Reference Materials in Electrolytic Conductivity Measurements
 Abstract:This paper reports a closed-flow-loop electrolytic conductivity measurement system enabling calibration of conductivity sensors from the conductivity level of ultrapure water (UPW) at /m up till the range of 10 to 140 mS/m, where stable certified reference materials (CRMs) for conductivity are available. The system is traceable to the SI unit system. A comparison made with another electrolytic conductivity measurement system, which is based on Jones-type conductivity cells designed to be used primarily for conductivities larger than ~10 mS/m, shows an agreement better than 0.1%. The most commonly used calibration method of conductivity sensors is based on CRMs and the extrapolation of the data to low conductivity values (/m). In contrast, the present closed-flow-loop electrolytic conductivity measurement system is based on the measurements made at conductivity levels where the sensor is used; it is, therefore, a better alternative. Autors: Carsten Thirstrup;Alan Snedden;Hans D. Jensen; Appeared in: IEEE Transactions on Instrumentation and Measurement Publication date: Oct 2017, volume: 66, issue:10, pages: 2745 - 2754 Publisher: IEEE
» Brillouin Backscattering Light Properties of Chaotic Laser Injecting Into an Optical Fiber
 Abstract:Laser diode-based optical chaos is attractive for the fundamental physics as well as practical tasks in such as secure communications, random number generation, and fiber sensing. The characteristics of Brillouin backscattering light generated by injecting a chaotic laser into a single mode fiber have been investigated experimentally. The Brillouin backscattering light still has the chaotic properties, and the position of the chaotic anti-Stokes frequency appears a dip, which has never been reported before. The power and linewidth variations of the Brillouin Stokes light and anti-Stokes light along with the input optical power also are analyzed. Particularly, we investigate the differences of Brillouin backscattering light between chaotic laser and narrow-linewidth laser, and analyze the interacted optical spectra when the chaotic laser and the narrow-linewidth laser inject into the 10 km single mode fiber simultaneously. With detailed analysis and experimental validation, we demonstrate that due to the chaotic self-similarity property, the chaotic laser at the location of anti-Stokes frequency transforms into the Stokes light in the stimulated Brillouin scattering process, which leads to the appearing of the dip. Autors: Mingjiang Zhang;Hui Liu;Jianzhong Zhang;Yi Liu;Ruixia Liu; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 10 Publisher: IEEE
» Broadband Decoupling Network for Dual-Band Microstrip Patch Antennas
 Abstract:Microstrip antenna (MSA) has become one of the most popular techniques in the modern communication systems because of its potentials in diversities of operating band and polarization. With the development of highly compact circuits, the isolation between each terminal of a multi-input-multi-output (MIMO) system becomes more and more important to reach high system accuracy. Here, we propose an innovative approach of decoupling for a dual-band MSA, in which the isolation is achieved through two kinds of transmission lines based on the substrate integrated waveguide (SIW) and miniaturized spoof surface plasmon polariton (SSPP). Both SIW and SSPP transmission lines have been used in functional devices and could be considered as part of radio frequency front-end circuits. Using the proposed method, the isolation between two ports of MSA is achieved without occupying extra space. A prototype is fabricated on the basis of a triple-layer dual-band MSA, each port of which is connected to one of the novel transmission lines. Combining the perfectly high-pass SIW and low-pass SSPP, the proposed feeding network could provide broadband decoupling without influencing the property of the antenna. We show that the mutual coupling between two ports is decreased by almost 20 dB within a wide frequency band. Such a design could meet the needs in application of multiantenna or tunable system without further alteration in dimensions and has potential to play an important role in the future communication systems. Autors: Bai Cao Pan;Tie Jun Cui; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 5595 - 5598 Publisher: IEEE
» Broadband Measurement Methodology for Specific Absorption Rates Above 300 MHz
 Abstract:Specific absorption rate (SAR) is an indicator of biological effects on human tissue caused by exposure to microwave radiation. An electric field probe scanning method has been traditionally used for SAR evaluation. However, since the electric field probe exhibits strong frequency dependence, it is difficult to evaluate SAR continuously in the broadband. In addition, preparing a physically different SAR measurement methodology from the electric field probe is an important task for validating measurement standards or regulations. Therefore, the authors developed a thermal SAR measurement method using optical fiber thermal sensors. In the present paper, we present a thermal SAR evaluation methodology that can be used in the broadband from 300 MHz to 6 GHz, which is frequently used by mobile devices. It was confirmed for the first time that SAR showed the peak with this continuous broadband measurement around 1.8 GHz. In addition, as a comparison measurement result with the electric field probe system and the proposed system, the mean value of each measured datum showed a deflection of approximately 10% to 20% in the whole frequency range. Autors: Yoshinobu Okano;Ryo Shimofusa;Mitsuki Anbai;Kaoru Someno; Appeared in: IEEE Transactions on Instrumentation and Measurement Publication date: Oct 2017, volume: 66, issue:10, pages: 2693 - 2702 Publisher: IEEE