Electrical and Electronics Engineering publications abstract of: 02-2018 sorted by title, page: 4

» Approximate Relations of Admittance for Symmetrically Arranged Dipoles
Abstract:
We previously proposed an approximate relation between admittance and , where is the admittance of a set of dipoles whose ports are located at their centers and is the admittance of the same set of dipoles with one is removed. Based on the relation, approximate expressions of were derived for the case that dipoles are symmetrically arranged. Their validity is examined by simulations and experiments in this communication.
Autors: Kyoichi Iigusa;Hirokazu Sawada;Fumihide Kojima;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2018, volume: 66, issue:2, pages: 984 - 989
Publisher: IEEE
 
» ARC Flash KPI Compliance at a Large Oil and Gas Company
Abstract:
An oil and gas company's arc flash electrical safe operations program is a corporate initiative to prevent electrical arc flash injuries. The program implements the company general instruction—electrical arc flash hazard mitigation, which provides minimum safe work requirements for protection of personnel in the workplace against electrical arc flash hazards in accordance with the National Fire Protection Agency 70E. The program tracks five key performance indicators (KPIs) to protect employees from arc flash hazards in all company facilities, which are as follows: 1) technology deployment; 2) training and certification; 3) operation and maintenance delineation; 4) operation and maintenance unified procedures; and 5) arc flash analysis. To verify compliance, the company initiated field-based assessments conducted by a specialized team of Power Systems Compliance and Electrical Engineers. The assessments are designed to validate each facility's compliance as well as to identify any opportunities for improvement in the application of arc flash mitigation. The assessors utilized a standardized checklist to determine the level to which established KPIs have been implemented. The checklists are weighted and scored to validate compliance in a consistent manner. This paper demonstrates a structured approach to measure arc flash KPI compliance and highlights some findings and practical examples that can be applied at many oil and gas facilities.
Autors: Ritchie Pragale;Amar Patel;Roger Bresden;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 889 - 894
Publisher: IEEE
 
» Arc Lighting Systems: The First Electrical Distribution Systems [History]
Abstract:
From about 1885 to 1915, the most common means of lighting streets was the use of arc lamps. These lamps and the systems by which they were supplied power were very technologically sophisticated. These were the first electrical distribution systems. The manufacturing companies that made the equipment for arc lighting went on to be the companies that launched the so-called electrical age.
Autors: Robert D. Barnett;
Appeared in: IEEE Power and Energy Magazine
Publication date: Feb 2018, volume: 16, issue:1, pages: 56 - 64
Publisher: IEEE
 
» Arena Function: A Framework for Computing Capacity Bounds in Wireless Networks
Abstract:
Bounds on the capacity of wireless networks often rely on simplifying assumptions and are given in terms of coarse network parameters, such as the number of nodes. While useful due to their simplicity, such bounds can significantly overestimate the achievable capacity in real-world situations, ignoring actual network topology and traffic patterns. The results of this paper improve such analytical results on network capacity in several ways. At the heart of our methodology lies the concept of transmission arenas, which indicates the presence of active transmissions near any given location in the network. This novel space-based approach is well-suited to untangle the interactions of simultaneous transmissions. Avoiding a graph-based model of the network, it opens new avenues of studying capacities. For homogeneous networks, we recover classical bounds. However, our methodology applies to arbitrary networks and can, thus, inform placing and activating of nodes also in the presence of clustering. Our method works with all classical channel models and dimensions. It provides bounds on the transport capacity which involve only high-level knowledge of node locations, such as the length of Euclidean minimum spanning tree. As an additional novelty, we establish bounds on wireless unicast and multicast capacities.
Autors: Alireza Keshavarz-Haddad;Rudolf H. Riedi;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Feb 2018, volume: 17, issue:2, pages: 1134 - 1146
Publisher: IEEE
 
» Array Waveguide Probe Loaded With Split-Ring Resonators for Sizing the Cracks in Metal Surface
Abstract:
Microwave nondestructive testing (NDT) technology developed rapidly, but crack detection in metal surface is facing many troubles, such as hard quantitation and low sensitivity. To solve these problems, this letter proposes a two-cell array waveguide microwave NDT probe with an array of split-ring resonators which operates at 12.5 GHz. It detects quantitatively tiny crack (as low as 0.5 mm) in metal surface. Maximum difference between simulation and experimental results is just 9%. Result shows that the peak distance of has a sensitive and quantitative link with the width and depth of crack. It is shown that the probe is capable of determining the location and dimension of surface cracks of a few millimeter depths and widths.
Autors: Xiaoqing Yang;Yang Yin;Di Zhang;Shiyue Wu;Kama Huang;Jianping Yuan;Zhanxia Zhu;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2018, volume: 28, issue:2, pages: 171 - 173
Publisher: IEEE
 
» Artificial-Noise-Aided Zero-Forcing Synthesis Approach for Secure Multi-Beam Directional Modulation
Abstract:
Great attention has been paid to wireless communication security in recent years. Directional modulation (DM) is one of the promising secure wireless communication techniques. Multi-beam DM has the capability of sending multiple data streams to cooperative users in different desired directions while distorting signal constellations in all other directions. Dynamic multi-beam DM has been proven to be more secure in real communication scenarios. However, previous synthesis approaches for dynamic multi-beam DM are relatively complex and demand a lot of computations. Therefore, an artificial-noise-aided zero-forcing synthesis approach is proposed. The calculation process of the baseband-weighted vector is simplified using the zero-forcing method, which is closely related to the concept of pseudo-inverse. The dynamic property of multi-beam DM is achieved by randomly changing the artificial noise vector. Compared with previous classical dynamic multi-beam DM synthesis approaches, the proposed approach is more efficient and easier to implement in practical systems with tolerable performance loss.
Autors: Tao Xie;Jiang Zhu;Yang Li;
Appeared in: IEEE Communications Letters
Publication date: Feb 2018, volume: 22, issue:2, pages: 276 - 279
Publisher: IEEE
 
» Arya: Operating System Support for Securely Augmenting Reality
Abstract:
Augmented reality (AR) applications capture sensor input from a user’s surroundings and overlay virtual output on their perception of the world, enabling new, immersive experiences. However, this technology raises serious security and privacy risks such as malicious or buggy AR output.
Autors: Kiron Lebeck;Kimberly Ruth;Tadayoshi Kohno;Franziska Roesner;
Appeared in: IEEE Security & Privacy
Publication date: Feb 2018, volume: 16, issue:1, pages: 44 - 53
Publisher: IEEE
 
» Assessment of Rigid Registration Quality Measures in Ultrasound-Guided Radiotherapy
Abstract:
Image guidance has become the standard of care for patient positioning in radiotherapy, where image registration is often a critical step to help manage patient motion. However, in practice, verification of registration quality is often adversely affected by difficulty in manual inspection of 3-D images and time constraint, thus affecting the therapeutic outcome. Therefore, we proposed to employ both bootstrapping and the supervised learning methods of linear discriminant analysis and random forest to help robustly assess registration quality in ultrasound-guided radiotherapy. We validated both approaches using phantom and real clinical ultrasound images, and showed that both performed well for the task. While learning-based techniques offer better accuracy and shorter evaluation time, bootstrapping requires no prior training and has a higher sensitivity.
Autors: Roozbeh Shams;Yiming Xiao;François Hébert;Matthew Abramowitz;Rupert Brooks;Hassan Rivaz;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Feb 2018, volume: 37, issue:2, pages: 428 - 437
Publisher: IEEE
 
» Asset-Based Dynamic Impact Assessment of Cyberattacks for Risk Analysis in Industrial Control Systems
Abstract:
With the evolution of information, communications, and technologies, modern industrial control systems (ICSs) face more and more cybersecurity issues. This leads to increasingly severe risks in critical infrastructure and assets. Therefore, risk analysis becomes a significant yet not well investigated topic for prevention of cyberattack risks in ICSs. To tackle this problem, a dynamic impact assessment approach is presented in this paper for risk analysis in ICSs. The approach predicts the trend of impact of cybersecurity dynamically from full recognition of asset knowledge. More specifically, an asset is abstracted with properties of construction, function, performance, location, and business. From the function and performance properties of the asset, object-oriented asset models incorporating with the mechanism of common cyberattacks are established at both component and system levels. Characterizing the evolution of behaviors for single asset and system, the models are used to analyze the impact propagation of cyberattacks. Then, from various possible impact consequences, the overall impact is quantified based on the location and business properties of the asset. A special application of the approach is to rank critical system parameters and prioritize key assets according to impact assessment. The effectiveness of the presented approach is demonstrated through simulation studies for a chemical control system.
Autors: Xuan Li;Chunjie Zhou;Yu-Chu Tian;Naixue Xiong;Yuanqing Qin;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2018, volume: 14, issue:2, pages: 608 - 618
Publisher: IEEE
 
» Asymmetric Bimanual Control of Dual-Arm Exoskeletons for Human-Cooperative Manipulations
Abstract:
In this paper, two upper limbs of an exoskeleton robot are operated within a constrained region of the operational space with unidentified intention of the human operator's motion as well as uncertain dynamics including physical limits. The new human-cooperative strategies are developed to detect the human subject's movement efforts in order to make the robot behavior flexible and adaptive. The motion intention extracted from the measurement of the subject's muscular effort in terms of the applied forces/torques can be represented to derive the reference trajectory of his/her limb using a viable impedance model. Then, adaptive online estimation for impedance parameters is employed to deal with the nonlinear and variable stiffness property of the limb model. In order for the robot to follow a specific impedance target, we integrate the motion intention estimation into a barrier Lyapunov function based adaptive impedance control. Experiments have been carried out to verify the effectiveness of the proposed dual-arm coordination control scheme, in terms of desired motion and force tracking.
Autors: Zhijun Li;Bo Huang;Arash Ajoudani;Chenguang Yang;Chun-Yi Su;Antonio Bicchi;
Appeared in: IEEE Transactions on Robotics
Publication date: Feb 2018, volume: 34, issue:1, pages: 264 - 271
Publisher: IEEE
 
» Asymptotic Comparison of ML and MAP Detectors for Multidimensional Constellations
Abstract:
A classical problem in digital communications is to evaluate the symbol error probability (SEP) and bit error probability (BEP) of a multidimensional constellation over an additive white Gaussian noise channel. In this paper, we revisit this problem for nonequally likely symbols and study the behavior of the optimal maximum a posteriori (MAP) detector at asymptotically high signal-to-noise ratios. Exact closed-form asymptotic expressions for SEP and BEP for arbitrary constellations and input distributions are presented. The well-known union bound is proven to be asymptotically tight under general conditions. The performance of the practically relevant maximum likelihood (ML) detector is also analyzed. Although the decision regions with MAP detection converge to the ML regions at high signal-to-noise ratios, the ratio between the MAP and ML detectors in terms of both SEP and BEP approaches a constant, which depends on the constellation and a priori probabilities. Necessary and sufficient conditions for asymptotic equivalence between the MAP and ML detectors are also presented.
Autors: Alex Alvarado;Erik Agrell;Fredrik Brännström;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 1231 - 1240
Publisher: IEEE
 
» Asymptotically Optimum Perfect Universal Steganography of Finite Memoryless Sources
Abstract:
A solution to the problem of asymptotically optimum perfect universal steganography of finite memoryless sources with a passive warden is provided, which is then extended to contemplate a distortion constraint. The solution rests on the fact that Slepian’s Variant I permutation coding implements first-order perfect universal steganography of finite host signals with optimum embedding rate. The duality between perfect universal steganography with asymptotically optimum embedding rate and lossless universal source coding with asymptotically optimum compression rate is evinced in practice by showing that permutation coding can be implemented by means of adaptive arithmetic coding. Next, a distortion constraint between the host signal and the information-carrying signal is considered. Such a constraint is essential whenever real-world host signals with memory (e.g., images, audio, or video) are decorrelated to conform to the memoryless assumption. The constrained version of the problem requires trading off embedding rate and distortion. Partitioned permutation coding is shown to be a practical way to implement this trade-off, performing close to an unattainable upper bound on the rate-distortion function of the problem.
Autors: Félix Balado;David Haughton;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 1199 - 1216
Publisher: IEEE
 
» Asynchronous Distributed Algorithms for Solving Linear Algebraic Equations
Abstract:
Two asynchronous distributed algorithms are presented for solving a linear equation of the form with at least one solution. The equation is simultaneously and asynchronously solved by agents assuming that each agent knows only a subset of the rows of the partitioned matrix , the estimates of the equation's solution generated by its neighbors, and nothing more. Neighbor relationships are characterized by a time-dependent directed graph whose vertices correspond to agents and whose arcs depict neighbor relationships. Each agent recursively updates its estimate of a solution at its own event times by utilizing estimates generated by its neighbors which are transmitted with delays. The event time sequences of different agents are not assumed to be synchronized. It is shown that for any matrix-vector pair for which the equation has a solution and any repeatedly jointly strongly connected sequence of neighbor graphs defined on the merged sequence of all agents’ event times, the algorithms cause all agents’ estimates to converge exponentially fast to the same solution to . The first algorithm requires a specific initialization step at each agent, and the second algorithm works for arbitrary initializations. Explicit expressions for convergence rates are provided, and a relation between local initializations and limiting consensus solutions is established, which is used to solve the least 2-norm solution.
Autors: Ji Liu;Shaoshuai Mou;A. Stephen Morse;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Feb 2018, volume: 63, issue:2, pages: 372 - 385
Publisher: IEEE
 
» Asynchronous Passive Multisensor System Observability With Unknown Sensor Position
Abstract:
A method is derived for forming composite measurements when the line-of-sight measurements from multiple sensors are asynchronous and the position(s) of one or more passive sensors is (are) unknown. Using the composite measurement, the target position, velocity, and unknown sensor location are estimated. Additionally, general analytical observability conditions are derived.
Autors: Itzik Klein;Yeshaya Lipman;Yaakov Bar-Shalom;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 369 - 375
Publisher: IEEE
 
» Asynchronous Task-Based Polar Decomposition on Single Node Manycore Architectures
Abstract:
This paper introduces the first asynchronous, task-based formulation of the polar decomposition and its corresponding implementation on manycore architectures. Based on a new formulation of the iterative dynamically-weighted Halley algorithm (QDWH) for the calculation of the polar decomposition, the proposed implementation replaces the original and hostile LU factorization for the condition number estimator by the more adequate factorization to enable software portability across various architectures. Relying on fine-grained computations, the novel task-based implementation is also capable of taking advantage of the identity structure of the matrix involved during the QDWH iterations, which decreases the overall algorithmic complexity. Furthermore, the artifactual synchronization points have been weakened compared to previous implementations, unveiling look-ahead opportunities for better hardware occupancy. The overall QDWH-based polar decomposition can then be represented as a directed acyclic graph (DAG), where nodes represent computational tasks and edges define the inter-task data dependencies. The StarPU dynamic runtime system is employed to traverse the DAG, to track the various data dependencies and to asynchronously schedule the computational tasks on the underlying hardware resources, resulting in an out-of-order task scheduling. Benchmarking experiments show significant improvements against existing state-of-the-art high performance implementations (i.e., Intel MKL and Elemental) for the polar decomposition on latest shared-memory vendors’ systems (i.e., Intel Haswell/Broadwell/Knights Landing, NVIDIA K80/P100 GPUs and - BM Power8), while maintaining high numerical accuracy.
Autors: Dalal Sukkari;Hatem Ltaief;Mathieu Faverge;David Keyes;
Appeared in: IEEE Transactions on Parallel and Distributed Systems
Publication date: Feb 2018, volume: 29, issue:2, pages: 312 - 323
Publisher: IEEE
 
» At the Heart of a Sustainable Energy Transition: The Public Acceptability of Energy Projects
Abstract:
Public acceptability is at the heart of changing the energy system toward a more sustainable way of energy production and use. Without public acceptability and support for changes, a sustainable energy transition is unlikely to be viable. We argue that public acceptability is often addressed too late and should be incorporated into the planning process from the start. Moreover, engineers, policy makers, and project developers tend to misjudge the complexity and causes of public resistance, trying to find the magic bullet to "solve" the lack of public acceptability. Such attempts are likely to be ineffective, or even counterproductive, if they fail to address people's key concerns surrounding energy projects. There is not a one-size-fits-all solution: public acceptability is a dynamic process that depends on the context, the specific project at stake, and the parties involved.
Autors: Goda Perlaviciute;Geertje Schuitema;Patrick Devine-Wright;Bonnie Ram;
Appeared in: IEEE Power and Energy Magazine
Publication date: Feb 2018, volume: 16, issue:1, pages: 49 - 55
Publisher: IEEE
 
» Atmospheric Humidity Sounding Using Differential Absorption Radar Near 183 GHz
Abstract:
A tunable G-band frequency-modulated continuous-wave radar system has been developed and used to perform differential absorption atmospheric humidity measurements for the first time. The radar’s transmitter uses high- power-handling GaAs Schottky diodes to generate between 15–23 dBm over a 10-GHz bandwidth near 183 GHz. By virtue of a high-isolation circular polarization duplexer, the monostatic radar’s receiver maintains a noise figure of about 7 dB even while the transmitter is on. With an antenna gain of 40 dB, high-SNR detection of light rain is achieved out to several hundred meters distance. Owing to the strong spectral dependence of the atmospheric absorption over the upper flank of the 183-GHz water absorption line, range-resolved measurements of absolute humidity can be obtained by ratioing the rain echoes over both range and frequency. Absorption measurements obtained are consistent with models of atmospheric millimeter-wave attenuation, and they demonstrate a new method for improving the accuracy of humidity measurements inside of clouds.
Autors: Ken B. Cooper;Raquel Rodriguez Monje;Luis Millán;Matthew Lebsock;Simone Tanelli;Jose V. Siles;Choonsup Lee;Andrew Brown;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Feb 2018, volume: 15, issue:2, pages: 163 - 167
Publisher: IEEE
 
» Attention Recognition in EEG-Based Affective Learning Research Using CFS+KNN Algorithm
Abstract:
The research detailed in this paper focuses on the processing of Electroencephalography (EEG) data to identify attention during the learning process. The identification of affect using our procedures is integrated into a simulated distance learning system that provides feedback to the user with respect to attention and concentration. The authors propose a classification procedure that combines correlation-based feature selection (CFS) and a k-nearest-neighbor (KNN) data mining algorithm. To evaluate the CFS+KNN algorithm, it was test against CFS+C4.5 algorithm and other classification algorithms. The classification performance was measured 10 times with different 3-fold cross validation data. The data was derived from 10 subjects while they were attempting to learn material in a simulated distance learning environment. A self-assessment model of self-report was used with a single valence to evaluate attention on 3 levels (high, neutral, low). It was found that CFS+KNN had a much better performance, giving the highest correct classification rate (CCR) of % for the valence dimension divided into three classes.
Autors: Bin Hu;Xiaowei Li;Shuting Sun;Martyn Ratcliffe;
Appeared in: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Publication date: Feb 2018, volume: 15, issue:1, pages: 38 - 45
Publisher: IEEE
 
» Authenticating Users Through Fine-Grained Channel Information
Abstract:
User authentication is the critical first step in detecting identity-based attacks and preventing subsequent malicious attacks. However, the increasingly dynamic mobile environments make it harder to always apply cryptographic-based methods for user authentication due to their infrastructural and key management overhead. Exploiting non-cryptographic based techniques grounded on physical layer properties to perform user authentication appears promising. In this work, the use of channel state information (CSI), which is available from off-the-shelf WiFi devices, to perform fine-grained user authentication is explored. Particularly, a user-authentication framework that can work with both stationary and mobile users is proposed. When the user is stationary, the proposed framework builds a user profile for user authentication that is resilient to the presence of a spoofer. The proposed machine learning based user-authentication techniques can distinguish between two users even when they possess similar signal fingerprints and detect the existence of a spoofer. When the user is mobile, it is proposed to detect the presence of a spoofer by examining the temporal correlation of CSI measurements. Both office building and apartment environments show that the proposed framework can filter out signal outliers and achieve higher authentication accuracy compared with existing approaches using received signal strength (RSS).
Autors: Hongbo Liu;Yan Wang;Jian Liu;Jie Yang;Yingying Chen;H. Vincent Poor;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Feb 2018, volume: 17, issue:2, pages: 251 - 264
Publisher: IEEE
 
» Automated Detection of Postictal Generalized EEG Suppression
Abstract:
Although there is no strict consensus, some studies have reported that Postictal generalized EEG suppression (PGES) is a potential electroencephalographic (EEG) biomarker for risk of sudden unexpected death in epilepsy (SUDEP). PGES is an epoch of EEG inactivity after a seizure, and the detection of PGES in clinical data is extremely difficult due to artifacts from breathing, movement and muscle activity that can adversely affect the quality of the recorded EEG data. Even clinical experts visually interpreting the EEG will have diverse opinions on the start and end of PGES for a given patient. The development of an automated EEG suppression detection tool can assist clinical personnel in the review and annotation of seizure files, and can also provide a standard for quantifying PGES in large patient cohorts, possibly leading to further clarification of the role of PGES as a biomarker of SUDEP risk. In this paper, we develop an automated system that can detect the start and end of PGES using frequency domain features in combination with boosting classification algorithms. The average power for different frequency ranges of EEG signals are extracted from the prefiltered recorded signal using the fast fourier transform and are used as the feature set for the classification algorithm. The underlying classifiers for the boosting algorithm are linear classifiers using a logistic regression model. The tool is developed using 12 seizures annotated by an expert then tested and evaluated on another 20 seizures that were annotated by 11 experts.
Autors: Wanchat Theeranaew;James McDonald;Bilal Zonjy;Farhad Kaffashi;Brian D. Moseley;Daniel Friedman;Elson So;James Tao;Maromi Nei;Philippe Ryvlin;Rainer Surges;Roland Thijs;Stephan Schuele;Samden Lhatoo;Kenneth A. Loparo;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Feb 2018, volume: 65, issue:2, pages: 371 - 377
Publisher: IEEE
 
» Automated Integrated Robotic Systems for Diagnostics and Test of Electric and Micropropulsion Thrusters
Abstract:
An integrated microcontroller-based data acquisition and robotic actuation suite comprising digital electronics, microcontrollers, custom-made hardware, and accessorial software for diagnostics, and characterization of electric propulsion thrusters in a large vacuum space environment simulator is designed, built, and tested. The components of the characterization suite have been aggregated into modular add-on units for rapid rearrangement and easy customization to suit various applications. The modules include a force calibration system for accurate thrust measurements in various thrust stands, and spatially resolved measurements in a multiprobe array comprising Langmuir and Faraday probes for plume diagnostics of plasma thrusters. Plume and thrust characteristics of a miniaturized Hall-type thruster were successfully measured in situ, enabling users to vary process controls and efficiently optimize the thruster performance. The system revealed a further potential for real-time flight mission diagnostics and control.
Autors: J. W. M. Lim;S. Y. Huang;L. Xu;J. S. Yee;R. Z. Sim;Z. L. Zhang;I. Levchenko;S. Xu;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Feb 2018, volume: 46, issue:2, pages: 345 - 353
Publisher: IEEE
 
» Automated Test Case Generation as a Many-Objective Optimisation Problem with Dynamic Selection of the Targets
Abstract:
The test case generation is intrinsically a multi-objective problem, since the goal is covering multiple test targets (e.g., branches). Existing search-based approaches either consider one target at a time or aggregate all targets into a single fitness function (whole-suite approach). Multi and many-objective optimisation algorithms (MOAs) have never been applied to this problem, because existing algorithms do not scale to the number of coverage objectives that are typically found in real-world software. In addition, the final goal for MOAs is to find alternative trade-off solutions in the objective space, while in test generation the interesting solutions are only those test cases covering one or more uncovered targets. In this paper, we present Dynamic Many-Objective Sorting Algorithm (DynaMOSA), a novel many-objective solver specifically designed to address the test case generation problem in the context of coverage testing. DynaMOSA extends our previous many-objective technique Many-Objective Sorting Algorithm (MOSA) with dynamic selection of the coverage targets based on the control dependency hierarchy. Such extension makes the approach more effective and efficient in case of limited search budget. We carried out an empirical study on 346 Java classes using three coverage criteria (i.e., statement, branch, and strong mutation coverage) to assess the performance of DynaMOSA with respect to the whole-suite approach (WS), its archive-based variant (WSA) and MOSA. The results show that DynaMOSA outperforms WSA in 28 percent of the classes for branch coverage (+8 percent more coverage on average) and in 27 percent of the classes for mutation coverage (+11 percent more killed mutants on average). It outperforms WS in 51 percent of the classes for statement coverage, leading to +11 percent more coverage on average. Moreover, DynaMOSA outperforms its predecessor MOSA for all the three coverage criteria in 19 percent of the classes with +8 percent more code coverage o- average.
Autors: Annibale Panichella;Fitsum Meshesha Kifetew;Paolo Tonella;
Appeared in: IEEE Transactions on Software Engineering
Publication date: Feb 2018, volume: 44, issue:2, pages: 122 - 158
Publisher: IEEE
 
» Automated Wavelength Alignment in a 4 × 4 Silicon Thermo-Optic Switch Based on Dual-Ring Resonators
Abstract:
We propose and experimentally demonstrate an automated resonance wavelength alignment scheme for an O -band 4 × 4 thermo-optic optical switch using dual-ring resonators. In this scheme, a new control algorithm based on saddle point searching is employed to align dual-input switching elements (SEs) and therefore the 4 × 4 switch. The proposed scheme is proven effective by demonstrating eight routing configurations for two 10-Gb/s data channels. The insertion losses of the three-stage SEs are ≤6.9 dB, and the crosstalk values are below −13.6 dB. Besides, the tolerance of the switch to the wavelength misalignment between the two optical input signals is measured. Negligible performance degradations are observed when the two channels are spaced by 0.05 nm.
Autors: Qingming Zhu;Xinhong Jiang;Yanping Yu;Ruiyuan Cao;Hongxia Zhang;Danping Li;Yanbo Li;Li Zeng;Xuhan Guo;Yong Zhang;Ciyuan Qiu;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 11
Publisher: IEEE
 
» Automatic 2-D/3-D Vessel Enhancement in Multiple Modality Images Using a Weighted Symmetry Filter
Abstract:
Automated detection of vascular structures is of great importance in understanding the mechanism, diagnosis, and treatment of many vascular pathologies. However, automatic vascular detection continues to be an open issue because of difficulties posed by multiple factors, such as poor contrast, inhomogeneous backgrounds, anatomical variations, and the presence of noise during image acquisition. In this paper, we propose a novel 2-D/3-D symmetry filter to tackle these challenging issues for enhancing vessels from different imaging modalities. The proposed filter not only considers local phase features by using a quadrature filter to distinguish between lines and edges, but also uses the weighted geometric mean of the blurred and shifted responses of the quadrature filter, which allows more tolerance of vessels with irregular appearance. As a result, this filter shows a strong response to the vascular features under typical imaging conditions. Results based on eight publicly available datasets (six 2-D data sets, one 3-D data set, and one 3-D synthetic data set) demonstrate its superior performance to other state-of-the-art methods.
Autors: Yitian Zhao;Yalin Zheng;Yonghuai Liu;Yifan Zhao;Lingling Luo;Siyuan Yang;Tong Na;Yongtian Wang;Jiang Liu;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Feb 2018, volume: 37, issue:2, pages: 438 - 450
Publisher: IEEE
 
» Automatic 3D Design for Efficiency Optimization of a Class E Power Amplifier
Abstract:
A design tool, which exploits a state–space model description for the automatic design of a class E power amplifier (PA), is here proposed. The tool provides an automatic optimization of the filter components, just by inserting the design specifications and the starting values. The second step of the automatic iterative tuning allows preserving the highest value of power efficiency. All specifications realize a 3 D matrix, which is able to converge (with 60 iterations in about 3 s) to an optimal solution by using the cross-check of the specifications. Finally, as a case study, an -optimal design has been implemented by using the proposed tool. We compare the analytical design of the class-E PA implemented in TSMC 65 nm CMOS technology, with the state space model technique here described. The new design reaches an efficiency of 87% in simulation, with an increment of 12% respect the original design.
Autors: Daniela De Venuto;Giovanni Mezzina;Jan Rabaey;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Feb 2018, volume: 65, issue:2, pages: 201 - 205
Publisher: IEEE
 
» Automatic Calcium Scoring in Low-Dose Chest CT Using Deep Neural Networks With Dilated Convolutions
Abstract:
Heavy smokers undergoing screening with low-dose chest CT are affected by cardiovascular disease as much as by lung cancer. Low-dose chest CT scans acquired in screening enable quantification of atherosclerotic calcifications and thus enable identification of subjects at increased cardiovascular risk. This paper presents a method for automatic detection of coronary artery, thoracic aorta, and cardiac valve calcifications in low-dose chest CT using two consecutive convolutional neural networks. The first network identifies and labels potential calcifications according to their anatomical location and the second network identifies true calcifications among the detected candidates. This method was trained and evaluated on a set of 1744 CT scans from the National Lung Screening Trial. To determine whether any reconstruction or only images reconstructed with soft tissue filters can be used for calcification detection, we evaluated the method on soft and medium/sharp filter reconstructions separately. On soft filter reconstructions, the method achieved F1 scores of 0.89, 0.89, 0.67, and 0.55 for coronary artery, thoracic aorta, aortic valve, and mitral valve calcifications, respectively. On sharp filter reconstructions, the F1 scores were 0.84, 0.81, 0.64, and 0.66, respectively. Linearly weighted kappa coefficients for risk category assignment based on per subject coronary artery calcium were 0.91 and 0.90 for soft and sharp filter reconstructions, respectively. These results demonstrate that the presented method enables reliable automatic cardiovascular risk assessment in all low-dose chest CT scans acquired for lung cancer screening.
Autors: Nikolas Lessmann;Bram van Ginneken;Majd Zreik;Pim A. de Jong;Bob D. de Vos;Max A. Viergever;Ivana Išgum;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Feb 2018, volume: 37, issue:2, pages: 615 - 625
Publisher: IEEE
 
» Automatic Correction of Dynamic Power Management Architecture in Modern Processors
Abstract:
The increasing demand for lower power forces designers to use sophisticated power management strategies such as multivoltage and power gating which are often accompanied with many design bugs. Correcting such bugs can be a time-consuming process that requires considerable manual efforts. In this paper, we propose a scalable automated method for correcting dynamic power management architectures by an incremental SAT-based mechanism. First, an initial counterexample (CEX) is generated by checking the equivalency between the specification model of the processor and its buggy implementation model. Then, we find two candidate solutions instead of one to satisfy this CEX. If two solutions are not equivalent, we generate new CEX in an iterative process which effectively converges into the final solution. The proposed method enables designers to correct multiple bugs such as missing isolation cells between two power domains, disordering in the sequence of control signals, error in the data restoring or saving, and powering off in always-on domains which are not addressed by existing methods. We have shown the effectiveness of our method on modern processors supporting complex power management mechanisms. The results confirm that our proposed method, respectively, reduces symbolic simulation steps and runtime by and compared to the state-of-the-art methods.
Autors: Reza Sharafinejad;Bijan Alizadeh;Zainalabedin Navabi;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Feb 2018, volume: 26, issue:2, pages: 308 - 318
Publisher: IEEE
 
» Automatic Defect Detection of Fasteners on the Catenary Support Device Using Deep Convolutional Neural Network
Abstract:
The excitation and vibration triggered by the long-term operation of railway vehicles inevitably result in defective states of catenary support devices. With the massive construction of high-speed electrified railways, automatic defect detection of diverse and plentiful fasteners on the catenary support device is of great significance for operation safety and cost reduction. Nowadays, the catenary support devices are periodically captured by the cameras mounted on the inspection vehicles during the night, but the inspection still mostly relies on human visual interpretation. To reduce the human involvement, this paper proposes a novel vision-based method that applies the deep convolutional neural networks (DCNNs) in the defect detection of the fasteners. Our system cascades three DCNN-based detection stages in a coarse-to-fine manner, including two detectors to sequentially localize the cantilever joints and their fasteners and a classifier to diagnose the fasteners’ defects. Extensive experiments and comparisons of the defect detection of catenary support devices along the Wuhan–Guangzhou high-speed railway line indicate that the system can achieve a high detection rate with good adaptation and robustness in complex environments.
Autors: Junwen Chen;Zhigang Liu;Hongrui Wang;Alfredo Núñez;Zhiwei Han;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Feb 2018, volume: 67, issue:2, pages: 257 - 269
Publisher: IEEE
 
» Automatic Identification of Driver’s Smartphone Exploiting Common Vehicle-Riding Actions
Abstract:
Texting or browsing the web on a smartphone while driving, called distracted driving, significantly increases the risk of car accidents. There have been a number of proposals for the prevention of distracted driving, but none of them has addressed its important challenges completely and effectively. To remedy this deficiency, we present an event-driven solution, called Automatic Identification of Driver’s Smartphone (AIDS), which identifies a driver’s smartphone by analyzing and fusing the phone’s sensory information related to common vehicle-riding activities, such as walking toward the vehicle, standing near the vehicle while opening a vehicle door, entering the vehicle, closing the door, and starting the engine. AIDS extracts features useful for identification of the driver’s phone from diverse sensors available in commodity smartphones. It identifies the driver’s phone before the vehicle leaves its parked spot, and differentiates seated (front or rear) rows in a vehicle by analyzing the subtle electromagnetic field spikes caused by the starting of the engine. To evaluate the feasibility and adaptability of AIDS, we have conducted extensive experiments: a prototype of AIDS was distributed to 12 participants, both males and females in their 20 and 30s, who have driven seven different vehicles for three days in real-world environments. Our evaluation results show that AIDS identified the driver’s phone with an 83.3-93.3 percent true positive rate while achieving a 90.1-91.2 percent true negative rate at a marginal increase of the phone’s energy consumption.
Autors: Homin Park;DaeHan Ahn;Taejoon Park;Kang G. Shin;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Feb 2018, volume: 17, issue:2, pages: 265 - 278
Publisher: IEEE
 
» Avoiding Matrix Inversion in Takagi–Sugeno-Based Advanced Controllers and Observers
Abstract:
Many of the recent advances on control and estimation of systems described by Takagi–Sugeno (TS) fuzzy models are based on matrix inversion, which could be a trouble in the case of real-time implementation. This paper is devoted to the development of alternative solutions to this matrix inversion problem in the discrete-time case. Two different methods are proposed: The first one relies on replacing the matrix inversion by multiple sums and the second methodology is based on an estimation of the matrix inversion by an observer structure. For the first methodology, a new class of controllers and observers are introduced which are called, respectively, the counterpart of an advanced TS-based (CATS) controller and the replica of an advanced TS-based (RATS) observer. Instead of relaxations for the linear matrix inequalities conditions, an original use of the membership functions is presented. In the second methodology, it is proposed the estimation-based control law for approximating TS-based (ECLATS) controller that uses a fuzzy state observer. The Lyapunov theory is used to ensure stability conditions for either the closed-loop system as well as the estimation error. Numerical examples and comparisons highlight the efficiency of the procedures that can be used to replace any inverted matrix in any advanced fuzzy controller or observer. Finally, advantages and drawbacks of the proposed method are discussed.
Autors: Thomas Laurain;Jimmy Lauber;Reinaldo Martinez Palhares;
Appeared in: IEEE Transactions on Fuzzy Systems
Publication date: Feb 2018, volume: 26, issue:1, pages: 216 - 225
Publisher: IEEE
 
» Bad Data Detection Using Linear WLS and Sampled Values in Digital Substations
Abstract:
Smart Grids employ intelligent control applications that require high quality data: fast, secure, and error free. Several researchers have focused on providing techniques for low latency and secured data links for these applications. Bad data detection is however generally provided only at the central level due to limitations in legacy technologies employed in many substations. With the introduction of IEC61850 data sharing within the substation becomes more flexible and transparent allowing more sophisticated management of data quality. Hence, this paper proposes a substation level bad data detection algorithm to facilitate also these types of requirements from applications. The algorithm is based on automatically detecting the substation topology by parsing standard substation description files and online state of circuit breakers and disconnectors. By applying linear weighted least square based state estimation algorithm, bad data from failing current transformers (CT) can be detected. By conducting the verification of different types of bad data, the results show the output of bad data detection algorithm provides higher accuracy than output from both measurement and protective CT in both static and faulty situations.
Autors: Yiming Wu;Yong Xiao;Fabian Hohn;Lars Nordström;Jianping Wang;Wei Zhao;
Appeared in: IEEE Transactions on Power Delivery
Publication date: Feb 2018, volume: 33, issue:1, pages: 150 - 157
Publisher: IEEE
 
» Balanced Filter With Wideband Common-Mode Suppression in Groove Gap Waveguide Technology
Abstract:
This letter is focused on the design and realization of balanced bandpass filters (BPFs) in gap waveguide technology. The procedure of filter design and resonance-mode selection to achieve the desired differential bandpass behavior with intrinsic deep and wideband common-mode suppression is explained. A third-order differential BPF is designed and fabricated for demonstration. Agreement between the computed and measured results validates the concept and the design procedure.
Autors: Ali K. Horestani;Mahmoud Shahabadi;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2018, volume: 28, issue:2, pages: 132 - 134
Publisher: IEEE
 
» Balanced Power Amplifier Protection Against Load Mismatch
Abstract:
This letter presents a new approach for balanced power amplifier protection against load mismatch under pulsed-RF operation. The proposed protection mechanism completely eliminates the reflected power under severe mismatch conditions while not affecting nominal operating condition. The concept is based on detection, comparison, and switching technique. The proposed protection circuit offers full protection against open and short at the output. This protection mechanism has been demonstrated on a 10-W -band power amplifier, intended to be used in space borne radar payloads. The reaction time of the proposed protection mechanism is <100 ns.
Autors: Shruti Sinha;Ch. V. N. Rao;Dhaval Pujara;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2018, volume: 28, issue:2, pages: 165 - 167
Publisher: IEEE
 
» Bandwidth Analysis of RF-DC Converters Under Multisine Excitation
Abstract:
The use of multisine signals to improve the efficiency of wireless power transfer (WPT) for low average received power was proposed recently. Several measurement-based studies illustrated the gain that can be achieved for different circuit or waveform instances, focusing on the impact of a time-varying amplitude on the rectifying efficiency. This paper first establishes a model enabling a thorough analysis of the multisine-based WPT system focusing on the bandwidth of the signal and the rectifier. This model enables a codesign of signal and rectifier for optimal WPT. The proposed model provides insight into the output voltage and power, as a function of the input waveform for different circuit models. By including the input matching and the clamper, our model is generic and can include a wide range of rectifiers with different voltage multiplication approaches. The key insight gained from our analysis is that there is a tradeoff between the frequency spacing of the tones of the multisine signal and the cut-off frequency of the low-pass RC filter, as a main property of the rectifier circuit. Our model predicts the measured power conversion efficiency and voltage with an error below 0.1 and 0.2 V, respectively.
Autors: Ning Pan;Daniel Belo;Mohammad Rajabi;Dominique Schreurs;Nuno Borges Carvalho;Sofie Pollin;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2018, volume: 66, issue:2, pages: 791 - 802
Publisher: IEEE
 
» Bandwidth Enhancement to Continuous-Time Input Pipeline ADCs
Abstract:
This paper presents design analysis and insights for a new continuous-time input pipeline (CTIP) analog-to-digital converter (ADC) architecture that has enhanced bandwidth. An all-pass filter-based analog delay in the signal path allows bandwidth extension to Nyquist signal bandwidths. A resetting integrator gain stage provides a signal path delay helping to increase the bandwidth while reducing the power cost. The noise filtering property of the resetting integrator gain stage preserves the medium resistive input benefit of CTIP ADCs. The resetting integrator allows the architecture to be implemented with a feedforward compensated op-amp using low-voltage CMOS processes. This paper has been verified by simulation results of a CTIP ADC with 1.2-V supply voltage designed in TSMC’s 65-nm CMOS technology.
Autors: Daniel O’Hare;Anthony G. Scanlan;Eric Thompson;Brendan Mullane;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Feb 2018, volume: 26, issue:2, pages: 404 - 415
Publisher: IEEE
 
» Barium Zirconate Nickelate as the Gate Dielectric for Low-Leakage Current Organic Transistors
Abstract:
High- barium zirconate nickelate (BZN) gate dielectric layer was prepared through the low-temperature sol–gel method and was used in pentacene-based organic thin-film transistor (OTFT) applications. In comparison with its barium zirconate oxide (BZO) counterpart, experimental results show that the threshold voltage of the BZN-based OTFTs decreases from −2 to −1.1 V, the gate leakage decreases from 10−8 to 10−12 A, the carrier mobility increases from 2.1 to 5.2 cm2/Vs, and the subthreshold swing decreases from 2.4 to 0.4 V/decade. The effect of Ni on device characteristics is discussed in this paper. Ni(II) acetylacetone possesses two pairs of symmetrical bidentate ligands, which can chelate with Zr ion to smoothen surface roughness. The dielectric constant can be increased. The enhancement of mobility is partly attributed to the smoother surface to reduce the scattering effects of the carrier. In addition, the improved film quality may also increase the barrier height and reduce the leakage current, which enhances the ON/ OFF ratio through the chelate effect due to the addition of Ni in BZO. Furthermore, excellent operation stability can be achieved.
Autors: Cheng-Jung Lee;Ke-Jing Lee;Yu-Chi Chang;Li-Wen Wang;Der-Wei Chou;Yeong-Her Wang;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2018, volume: 65, issue:2, pages: 680 - 686
Publisher: IEEE
 
» Battery-Less Short-Term Smoothing of Photovoltaic Generation Using Sky Camera
Abstract:
There is a growing concern over addressing the adverse effects of variations in the output power of distributed generators such as photovoltaic generation (PVG) systems that continue to be widely introduced into power networks. Nowadays, most network operators are requiring these intermittent energy resources to seek compliance with new regulations pertaining to the restriction of their export power fluctuations. This paper aims to investigate the smoothing of the export power fluctuations primarily attributed to clouds passing over the PVG plant, which are traditionally compensated by integrating a battery storage (BS) system. The idea of incorporating short-term solar prediction information into the conventional smoothing approach is examined to indicate how it affects the engagement of BS in the smoothing process. Afterward, an enhanced solar forecasting scheme based on whole-sky imaging is proposed and its performance is demonstrated through several real-time experiments complemented with simulation studies. The results reveal that the proposed PVG smoothing strategy is capable of successfully filtering rapid export power fluctuations to an acceptable extent and the conventional generation reserves will experience a negligible amount of remaining undesired power variation. This clearly bears out the hypothesis of battery-less PVG regulation.
Autors: Mojtaba Saleh;Lindsay Meek;Mohammad A. S. Masoum;Masoud Abshar;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2018, volume: 14, issue:2, pages: 403 - 414
Publisher: IEEE
 
» Bayesian Particle Tracking of Traffic Flows
Abstract:
We develop a Bayesian particle filter for tracking traffic flows that is capable of capturing non-linearities and discontinuities present in flow dynamics. Our model includes a hidden state variable that captures sudden regime shifts between traffic free flow, breakdown, and recovery. We develop an efficient particle learning algorithm for real time online inference of states and parameters. This requires a two-step approach, first resampling the current particles with a mixture predictive distribution and second propagation of states using the conditional posterior distribution. Particle learning of parameters follows from updating recursions for conditional sufficient statistics. To illustrate our methodology, we analyze the measurements of daily traffic flow from the Illinois Interstate I-55 highway system. We demonstrate how our filter can be used to infer the change of traffic flow regime on a highway road segment based on a measurement from freeway single-loop detectors. Finally, we conclude with directions for future research.
Autors: Nicholas Polson;Vadim Sokolov;
Appeared in: IEEE Transactions on Intelligent Transportation Systems
Publication date: Feb 2018, volume: 19, issue:2, pages: 345 - 356
Publisher: IEEE
 
» Bayesian Test for Detecting False Data Injection in Wireless Relay Networks
Abstract:
We develop the Bayesian test for detecting the relay misbehavior (false data injection) at the packet level in lossy one-way wireless relay networks. The proposed approach exploits overheard erroneous packet from the source as a reference in verifying the correctness of relayed packet at the destination. We derive the probability of false alarm and missed detection as a function of the overhearing error rate, the number of bits modified in a packet, and the packet length. We show that the probability of false alarm and missed detection decreases as the packet length increases and converges to zero, regardless of the overhearing error rate, if the packet length is sufficiently long.
Autors: Xudong Liu;Yong Guan;Sang Wu Kim;
Appeared in: IEEE Communications Letters
Publication date: Feb 2018, volume: 22, issue:2, pages: 380 - 383
Publisher: IEEE
 
» Beam Shaping Freeform Lens Design With Modified Optical Flux Partition
Abstract:
A freeform lens design strategy that performs directivity transformation is proposed. In principle, arbitrary beam pattern can be achieved with this method, which uses a modified flux partition method. Taking a Lambertian light source as the example, this method successfully give different required intensity distributions, such as the isotropic and exponential ones. Also, the isotropic directivity lens is fabricated and the beam pattern is measured to verify the effectiveness. With a real Lambertian top emitting white light LED as the source, the experimental results agree well with the simulation ones, which provides high directivity isotropy (more than 80%). This scheme takes Fresnel loss of the lens into consideration and can also predict the efficiency of the lens; it may find applications in lighting or illumination engineering where directivity transformation are required.
Autors: Pin Han;Hsun-Ching Hsu;Cheng-Mu Tsai;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 13
Publisher: IEEE
 
» Beam Switching Antenna Based on a Reconfigurable Cascaded Feeding Network
Abstract:
In this paper, a beam switching antenna (BSA) based on a reconfigurable cascaded feeding network (RCFN) is presented. The RCFN is engineered by cascading several varactor-loaded quasi-lumped couplers (QLCs). As the output port of the RCFN, the coupled port of every QLC is connected to an endfire radiator. BSAs based on two types of RCFN, the open-loop RCFN and closed-loop RCFN, are designed, simulated, and measured. The open-loop design features flexible beam switching strategies with the dynamic control of operation modes allocating the input power to the intended radiator(s), and single-/multibeam switching is achieved. In the case of the closed-loop RCFN, a power-recycling circuit is introduced to improve the efficiency of the single-beam switching mode of the BSA. Measured results show that the BSA operating in single-beam mode is able to radiate six switched beams each with a 3 dB beamwidth of 60°, covering 360° in the azimuth plane. The return losses and gain fluctuation of both prototypes are better than 15 dB and less than 1 dB, respectively. The corresponding experiments agree well with both the theoretical analysis and the simulation results.
Autors: Peng-Yuan Wang;Tao Jin;Fan-Yi Meng;Yue-Long Lyu;Daniel Erni;Qun Wu;Lei Zhu;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2018, volume: 66, issue:2, pages: 627 - 635
Publisher: IEEE
 
» Beam-Shaping Technique Based on Generalized Laws of Refraction and Reflection
Abstract:
In this paper, we present a new beam-shaping technique based on the use of a flat lens comprised of phase shift structures (PSSs), designed to reshape the primary beam into a desired one. The beam impinging upon the input port of the lens is regarded as a set of ray tubes, whose refraction characteristics are modified by the PSSs based on the generalized law of refraction to form the desired shaped beam. The proposed method is straightforward to implement and is general purpose in nature. The design procedure of the beam-shaping flat lens is discussed in detail, and two example designs are presented. The simulation and measured results of these case examples confirm that the BSFLs can reshape the primary beams of the feed antennas to the desired flattop or isoflux patterns, for instance. Finally, extensions of the proposed technique to other potential applications are discussed.
Autors: Pengfei Zhang;Shuxi Gong;Raj Mittra;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2018, volume: 66, issue:2, pages: 771 - 779
Publisher: IEEE
 
» Beampattern Synthesis for Frequency Diverse Array via Reweighted $ell _1$ Iterative Phase Compensation
Abstract:
This paper addresses the issue of beampattern synthesis with flexible magnitude response and low sidelobe in a frequency diverse array radar. It is formulated as an optimization problem in terms of -norm minimization, which encourages the sparsity of array pattern. An iterative phase compensation (IPC) technique is employed to transform the nonconvex constraint to phase compensation form. Then, to further reduce the sidelobe level, a reweighted -IPC algorithm is devised, in which a sparsity-enhanced scheme is utilized to convert the -norm to a new cost function that more closely resembles -norm. Numerical results are presented to demonstrate the effectiveness of the proposed approach in different scenarios.
Autors: Qiang Li;Lei Huang;Peichang Zhang;Hing Cheung So;Huifeng Xue;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 467 - 475
Publisher: IEEE
 
» Benchmarking of Constant Power Generation Strategies for Single-Phase Grid-Connected Photovoltaic Systems
Abstract:
With a still increase of grid-connected photovoltaic (PV) systems, challenges have been imposed on the grid due to the continuous injection of a large amount of fluctuating PV power, like overloading the grid infrastructure (e.g., transformers) during peak power production periods. Hence, advanced active power control methods are required. As a cost-effective solution to avoid overloading, a constant power generation (CPG) control scheme by limiting the feed-in power has been introduced into the currently active grid regulations. In order to achieve a CPG operation, this paper presents three CPG strategies based on a power control method (P-CPG), a current limit method (I-CPG), and the perturb and observe algorithm (P&O-CPG). However, the operational mode changes (e.g., from the maximum power point tracking to a CPG operation) will affect the entire system performance. Thus, a benchmarking of the presented CPG strategies is also conducted on a 3-kW single-phase grid-connected PV system. Comparisons reveal that either the P-CPG or I-CPG strategies can achieve fast dynamics and satisfactory steady-state performance. In contrast, the P&O-CPG algorithm is the most suitable solution in terms of high robustness, but it presents poor dynamic performance.
Autors: Ariya Sangwongwanich;Yongheng Yang;Frede Blaabjerg;Huai Wang;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 447 - 457
Publisher: IEEE
 
» Bi-level and Bi-objective p-Median Type Problems for Integrative Clustering: Application to Analysis of Cancer Gene-Expression and Drug-Response Data
Abstract:
Recent advances in high-throughput technologies have given rise to collecting large amounts of multidimensional heterogeneous data that provide diverse information on the same biological samples. Integrative analysis of such multisource datasets may reveal new biological insights into complex biological mechanisms and therefore remains an important research field in systems biology. Most of the modern integrative clustering approaches rely on independent analysis of each dataset and consensus clustering, probabilistic or statistical modeling, while flexible distance-based integrative clustering techniques are sparsely covered. We propose two distance-based integrative clustering frameworks based on bi-level and bi-objective extensions of the p-median problem. A hybrid branch-and-cut method is developed to find global optimal solutions to the bi-level p-median model. As to the bi-objective problem, an -constraint algorithm is proposed to generate an approximation to the Pareto optimal set. Every solution found by any of the frameworks corresponds to an integrative clustering. We present an application of our approaches to integrative analysis of NCI-60 human tumor cell lines characterized by gene expression and drug activity profiles. We demonstrate that the proposed mathematical optimization-based approaches outperform some state-of-the-art and traditional distance-based integrative and non-integrative clustering techniques.
Autors: Anton V. Ushakov;Xenia Klimentova;Igor Vasilyev;
Appeared in: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Publication date: Feb 2018, volume: 15, issue:1, pages: 46 - 59
Publisher: IEEE
 
» Biased Constrained Hybrid Kalman Filter for Range-Based Indoor Localization
Abstract:
The range-based localization method is widely used in wireless sensor localization systems. Many existing localization algorithms are unbiased estimators. However, the estimation performance presents biased features in the real localization systems. On the other hand, many biased location estimators show some essential advantages over unbiased estimators, e.g., robust to the noise, more accurate estimation, and low complexity. In this paper, we deeply investigate the performance of biased estimator, min–max, to achieve a new accuracy limit, and propose a hybrid Kalman filtering algorithm, which recursively locates the target based on biased feature. The first contribution is that we formulate the biased Cramér-Rao lower bound of the min–max algorithm to indicate that the biased localization algorithm can outperform the unbiased algorithms, e.g., maximum likelihood, as if the estimation bias were attained. The second contribution is that we propose a hybrid Kalman filtering algorithm while employing the min–max to construct a constrain region and using the dynamic Gaussian model for calculation in non-Gaussian environments. Our algorithm is robust to complicated environments with high accuracy. And, we implement it in an IoT target tracking platform. Both theoretical analysis and experimental evaluation indicate that the proposed algorithm outperform the unbiased optimal estimation methods. And our algorithm can control the estimation error in only 1 m.
Autors: Yubin Zhao;Xiaofan Li;Yang Wang;Cheng-Zhong Xu;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1647 - 1655
Publisher: IEEE
 
» Bilateral LSTM: A Two-Dimensional Long Short-Term Memory Model With Multiply Memory Units for Short-Term Cycle Time Forecasting in Re-entrant Manufacturing Systems
Abstract:
Forecasting short-term cycle time (CT) of wafer lots is crucial for production planning and control in the wafer manufacturing. A novel recurrent neural network called “bilateral long short-term memory (bilateral LSTM)” is proposed to model a short-term cycle time forecasting (CTF) of each re-entrant period of a wafer lot. First, a two-dimensional (2-D) architecture is designed to transmit the wafer and layer correlations by using wafer and layer connections. Subsequently, aiming to store various error signals caused by the diverse CT data, a multiply memory structure is presented to extend the capacity of constant error carousel (CEC) in the LSTM model. The experiment results indicate that the proposed model outperforms conventional models in the accuracy and stability for the short-term CTF. Further comparative experiments reveal that the 2-D architecture can enhance the prediction accuracy and the multi-CEC structure can improve the forecasting stability for the short-term CTF of wafer lots.
Autors: Junliang Wang;Jie Zhang;Xiaoxi Wang;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2018, volume: 14, issue:2, pages: 748 - 758
Publisher: IEEE
 
» Bilevel Multiview Latent Space Learning
Abstract:
Different kinds of features describe different aspects of image data, and each feature can be treated as a view when we take it as a particular understanding of images. Leveraging multiple views provides a richer and comprehensive description than using only a single view. However, multiview data are often represented by high-dimensional heterogeneous features, so it is meaningful to find a low-dimensional consensus representation from multiple views. In this paper, we propose an unsupervised multiview dimensionality reduction method for images based on bilevel latent space learning. As different views have different physical meanings and statistical properties, they are not directly comparable. Therefore, we learn the comparable representation for each view in the first level. The shared and the private nature of multiview data are exploited to accurately preserve the information of each view. Then, we fuse different views into a low-dimensional representation by conducting joint matrix factorization in the second level. To guarantee the low-dimensional representation to be compact and discriminative, the intrinsic geometric structure of data is utilized. Besides, our method considers resisting the outliers and noise contained in multiview data, which may influence the learned representation and deteriorate its semantic consistency. We design appropriate optimization objectives to learn the latent spaces in different levels. Compared with the existing methods, our method could provide a more flexible multiview learning strategy that not only accurately captures the information of each view but also is robust to outliers and noise, which can obtain a more discriminative and compact low-dimensional representation. Experiments on two real-world image data sets demonstrate the advantages of our method over the existing multiview dimensionality reduction methods.
Autors: Zhe Xue;Guorong Li;Shuhui Wang;Weigang Zhang;Qingming Huang;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Feb 2018, volume: 28, issue:2, pages: 327 - 341
Publisher: IEEE
 
» Black Phosphorus: A New Platform for Gaseous Sensing Based on Surface Plasmon Resonance
Abstract:
We numerically demonstrate and propose sensitivity enhancement of surface plasmon resonance (SPR)-based conventional gaseous sensor using few layers of black phosphorous (BP), as compared with other 2D material such as graphene and molybdenum disulphide (MoS2). Results of our optimized numerical study show that with implementation of bilayer BP over a conventional gaseous sensor, sensitivity enhances by ~35%, which is further increased up to ~73% by addition of a monolayer MoS2 at an operating wavelength nm. Therefore, the proposed SPR gaseous sensor could potentially open a new platform for high-performance gaseous sensing in the visible region.
Autors: Triranjita Srivastava;Rajan Jha;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:4, pages: 319 - 322
Publisher: IEEE
 
» BLDC Motor Drive Based on Bridgeless Landsman PFC Converter With Single Sensor and Reduced Stress on Power Devices
Abstract:
The Landsman converter based on a power factor correction (PFC) in bridgeless (BL) configuration feeding a brushless dc motor (BLDCM) drive is proposed for low-power household appliances. The conduction losses associated with diodes are reduced by BL configuration and switching losses of solid-state switches of voltage source inverter are reduced by the use of low frequency switching signals in electronic commutation for the BLDCM. The front-end BL PFC based Landsman converter operating in the discontinuous inductor current mode is used for controlling the dc link voltage, and PFC is attained naturally with reduced conduction losses and switch stress. A single voltage sensor is used for controlling the dc bus voltage. A prototype is developed to study performance of the system for wide range speed control and power quality improvement. The experimental performance of BLDCM is presented for its functions at varying voltages of ac mains (90–265 V) to adhere to the limits defined by IEC61000-3-2 standard.
Autors: Praveen Kumar Singh;Bhim Singh;Vashist Bist;Kamal Al-Haddad;Ambrish Chandra;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 625 - 635
Publisher: IEEE
 
» Blind Channel Estimation and Symbol Detection for Multi-Cell Massive MIMO Systems by Expectation Propagation
Abstract:
Massive MIMO systems exploit the favorable propagation condition of the radio channel, whereby the vector-valued channels between the base station (BS) and the terminals become mutually orthogonal. This property is used in a recently-proposed channel estimation method for multi-cell massive MIMO systems based on the eigenvalue decomposition (EVD) of the correlation matrix of the received vectors. In this paper, we present a blind channel estimation and symbol detection scheme for multi-cell massive MIMO systems based on expectation propagation (EP). The proposed algorithm is initialized with the channel estimation result from the EVD-based method. It is shown that in our EP formulation, channel estimation and symbol detection are “decoupled” in that EP iterations for channel estimation can be performed without the knowledge of the specific transmitted symbols. Therefore, channel estimation can be performed first followed by symbol detection. In particular, a liner symbol detection scheme such as zero-forcing (ZF) or minimum mean-squared error (MMSE) algorithm may be employed. Simulation results show that after a few iterations, the EP-based algorithm significantly improves the performance of the EVD-based method in both channel estimation and symbol error rate. Comparisons are also made with the results from a recently proposed blind detection scheme and it is shown that the proposed algorithm has better performance.
Autors: Kamran Ghavami;Mort Naraghi-Pour;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Feb 2018, volume: 17, issue:2, pages: 943 - 954
Publisher: IEEE
 
» Blind Demixing and Deconvolution at Near-Optimal Rate
Abstract:
We consider simultaneous blind deconvolution of source signals from their noisy superposition, a problem also referred to blind demixing and deconvolution. This signal processing problem occurs in the context of the Internet of Things where a massive number of sensors sporadically communicate only short messages over unknown channels. We show that robust recovery of message and channel vectors can be achieved via convex optimization when random linear encoding using i.i.d. complex Gaussian matrices is used at the devices and the number of required measurements at the receiver scales with the degrees of freedom of the overall estimation problem. Since the scaling is linear in our result significantly improves over recent works.
Autors: Peter Jung;Felix Krahmer;Dominik Stöger;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 704 - 727
Publisher: IEEE
 
» Blinding Guidance Against Missiles Sharing Bearings-Only Measurements
Abstract:
A novel “blind and evade” guidance concept for an aerial target, which is exposed to a threat of two homing missiles, is presented. Each missile is assumed to measure solely its own line-of-sight (LOS) angle and share it with the other missile. Such information sharing enables the missiles to form a triangular measuring baseline relative to the target and to improve their estimation accuracy. However, if the separation angle between the two LOS vectors is small enough, the observability of such double-LOS measuring approach becomes weak. Motivated by this observation, the idea of the proposed concept is to bring the missiles on the same LOS with the target, i.e., blinding them, and then perform an appropriately timed target evasive maneuver. The target's guidance law is derived under the assumption of perfect information and formulated as an optimal control problem. Simulation results demonstrate the potential of the proposed defense concept.
Autors: Robert Fonod;Tal Shima;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 205 - 216
Publisher: IEEE
 
» Block-Stream as a Service: A More Secure, Nimble, and Dynamically Balanced Cloud Service Model for Ambient Computing
Abstract:
Cloud computing has become mainstream in the last few years. Diverse services based on IaaS, PaaS, SaaS, and app store models have been widely available to millions of users worldwide. At the same time, transparent computing (TC) has also gained strong interest in China. With the rapid development of IoT, increasing IoT devices will be deployed to provide information services for end users. As we are heading into the era of ambient computing, where end users are immersed in seamless computing devices and services, the boundary between cloud and devices is getting blurry, and more devices and services need to be securely managed. The existing service models that are defined for user-cloud interaction should be extended to serve more diverse and lightweight devices with nimble and fluid services. With this evolution trend, it is paramount for both cloud service providers and IoT service operators to manage the security and integrity of these services. In this article, we propose a new cloud service model, named block-stream as a service (BaaS), based on our previous study on TC. BaaS is nimbler than SaaS and has better security management than an app store. It is expected that this new cloud service model has great potential to support the vision of ambient computing and securely manage diverse applications on lightweight IoT devices.
Autors: Jackson He;Yaoxue Zhang;Ju Lu;Ming Wu;Fujin Huang;
Appeared in: IEEE Network
Publication date: Feb 2018, volume: 32, issue:1, pages: 126 - 132
Publisher: IEEE
 
» Book Reviews [7 Reviews]
Abstract:
The following books are reviewed: Extreme-Temperature and Harsh-Environment Electronics by V. K. Khanna; Advances in Magnetic Materials—Processing, Properties, and Performance by S. Zhang and D. Zhao; Self-Healing Materials by G. Wypych; Renewable Energy Integration, 2nd Edition by L. E. Jones; High-Power Converters and AC Drives, 2nd Edition by B. Wu and M. Narimani; Power System SCADA and Smart Grids by M. S. Thomas and J. D. McDonald; Energy Storage by G. M. Crawley.
Autors: John J. Shea;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Feb 2018, volume: 34, issue:1, pages: 64 - 67
Publisher: IEEE
 
» Boost-Phase Trajectory Inference From Space-Borne LOS Measurements With a Sieve Method
Abstract:
Boost-phase trajectory inference is one of the major objectives of the space-borne missile early-warning system. Traditional methods can be classified as either profile-based or profile-free methods. The profile-based methods are accurate but inadaptable to the types of missiles, whereas the profile-free methods are adaptable but inaccurate. To integrate the strengths of the profile-based and profile-free methods, a multimodel trajectory inference approach is proposed. First, a general net acceleration model (GNAM) containing only type-free prior information is constructed by the method of sieves. Then, a new kind of net acceleration profile is proposed by incorporating type-dependent prior information into the GNAM. After that, the multimodel approach is proposed following the Bayesian framework. Simulations indicate that the approach is accurate in estimation and capable for type identification.
Autors: Taihe Yi;Bing Liu;Zhengming Wang;Zhen Shen;Dongyun Yi;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 339 - 352
Publisher: IEEE
 
» Boosted Random Ferns for Object Detection
Abstract:
In this paper we introduce the Boosted Random Ferns (BRFs) to rapidly build discriminative classifiers for learning and detecting object categories. At the core of our approach we use standard random ferns, but we introduce four main innovations that let us bring ferns from an instance to a category level, and still retain efficiency. First, we define binary features on the histogram of oriented gradients-domain (as opposed to intensity-), allowing for a better representation of intra-class variability. Second, both the positions where ferns are evaluated within the sliding window, and the location of the binary features for each fern are not chosen completely at random, but instead we use a boosting strategy to pick the most discriminative combination of them. This is further enhanced by our third contribution, that is to adapt the boosting strategy to enable sharing of binary features among different ferns, yielding high recognition rates at a low computational cost. And finally, we show that training can be performed online, for sequentially arriving images. Overall, the resulting classifier can be very efficiently trained, densely evaluated for all image locations in about 0.1 seconds, and provides detection rates similar to competing approaches that require expensive and significantly slower processing times. We demonstrate the effectiveness of our approach by thorough experimentation in publicly available datasets in which we compare against state-of-the-art, and for tasks of both 2D detection and 3D multi-view estimation.
Autors: Michael Villamizar;Juan Andrade-Cetto;Alberto Sanfeliu;Francesc Moreno-Noguer;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Feb 2018, volume: 40, issue:2, pages: 272 - 288
Publisher: IEEE
 
» Bootstrapping and Resetting CMOS Starter for Thermoelectric and Photovoltaic Chargers
Abstract:
Sustaining microsensors for years is challenging because tiny batteries exhaust quickly, and recharging or replacing thousands of networked nodes is impracticable. Harnessing heat or light energy helps, but only when available. And even then, tiny generators output less than 300 mV, which is not enough to operate microelectronics well. This brief presents a 0.18-m CMOS starter that charges a temporary 1.8-V supply quickly and reliably from slow- or fast-rising photovoltaic and thermoelectric sources. For this, a jump starter helps an LC tank oscillate to a level that allows a discharge path to output power. A resetter then continually resets the circuit until the system senses the temporary supply is ready. This way, with 1.8 V, a charging system can then charge a battery quickly before the onset of another harvesting drought. The starter does not require off-chip components because it borrows the switched inductor that the charging system already uses to charge the battery. A prototype of the starter proposed charges 120 pF to 1.8 V in 15–59 s with 1.5%–7% efficiency from a 180 , 220–250-mV source.
Autors: Andrés A. Blanco;Gabriel A. Rincón-Mora;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Feb 2018, volume: 65, issue:2, pages: 156 - 160
Publisher: IEEE
 
» Boundary Estimation of Imaged Object in Microwave Medical Imaging Using Antenna Resonant Frequency Shift
Abstract:
The performance of microwave imaging systems can be significantly improved by incorporating boundaries of the imaged object as a priori information. While it might be possible to manually measure that boundary in a controlled laboratory environment, this cannot be achieved in the clinical environment due to the impracticality of such a measurement in addition to the effect of the natural subject’s movement. In this paper, a method for boundary identification at the same time of imaging and using the same data captured for imaging is presented. The method is based on the relation between the imaging antennas’ resonant frequency and the location of the imaged object. The imaging antennas’ resonant frequency shifts when that antenna faces an imaging object, which is effectively a lossy dielectric in biomedical application, and that shift depends on the distance between the antenna and the object. The proposed technique is quite fast in scanning, computation, and image creation as it does not need additional devices for accurate boundary estimation. The method is tested via simulations and human trials using a torso imaging system. The collected data across the band 0.75–1.75 GHz using a 12-element antenna array, which is extended to 24 virtual elements, enclosing the human torso are processed to successfully estimate the torso boundary in a more accurate way than other methods. The included results in imaging a lung cancer case indicate that the accurate detection of the torso boundary improves microwave images.
Autors: Ali Zamani;S. Ahdi Rezaeieh;Konstanty S. Bialkowski;Amin M. Abbosh;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2018, volume: 66, issue:2, pages: 927 - 936
Publisher: IEEE
 
» Bounds and Constructions for Optimal $(n, {3, 4, 5}, Lambda _a, 1, Q)$ -OOCs
Abstract:
Let be a set of positive integers, a positive integer, an -tuple of positive integers, and an -tuple of positive rational numbers whose sum is 1. In 1996, Yang introduced variable-weight optical orthogonal code, -OOC, for multimedia optical CDMA systems with multiple quality of service (QoS) requirements. Some work had been done on the constructions of optimal -OOCs with unequal auto-correlation constraints for and {3, 5}, while little is known on optimal -OOCs for . In this paper, we focus our main attentions on -OOCs with . Tight upper bounds on the maximum code size of -OOCs are obtained, and infinite classes of optimal -OOCs are constructed.
Autors: Huangsheng Yu;Shujuan Dang;Dianhua Wu;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 1361 - 1367
Publisher: IEEE
 
» Brain MR Image Restoration Using an Automatic Trilateral Filter With GPU-Based Acceleration
Abstract:
Objective: Noise reduction in brain magnetic resonance (MR) images has been a challenging and demanding task. This study develops a new trilateral filter that aims to achieve robust and efficient image restoration. Methods: Extended from the bilateral filter, the proposed algorithm contains one additional intensity similarity funct-ion, which compensates for the unique characteristics of noise in brain MR images. An entropy function adaptive to intensity variations is introduced to regulate the contributions of the weighting components. To hasten the computation, parallel computing based on the graphics processing unit (GPU) strategy is explored with emphasis on memory allocations and thread distributions. To automate the filtration, image texture feature analysis associated with machine learning is investigated. Among the 98 candidate features, the sequential forward floating selection scheme is employed to acquire the optimal texture features for regularization. Subsequently, a two-stage classifier that consists of support vector machines and artificial neural networks is established to predict the filter parameters for automation. Results: A speedup gain of 757 was reached to process an entire MR image volume of 256 × 256 × 256 pixels, which completed within 0.5 s. Automatic restoration results revealed high accuracy with an ensemble average relative error of 0.53 ± 0.85% in terms of the peak signal-to-noise ratio. Conclusion: This self-regulating trilateral filter outperformed many state-of-the-art noise reduction methods both qualitatively and quantitatively. Significance: We believe that this new image restoration algorithm is of potential in many brain MR image processing applications that require expedition and automation.
Autors: Herng-Hua Chang;Cheng-Yuan Li;Audrey Haihong Gallogly;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Feb 2018, volume: 65, issue:2, pages: 400 - 413
Publisher: IEEE
 
» Bridged-T Coil for Miniature Dual-Band Branch-Line Coupler and Power Divider Designs
Abstract:
In this paper, a new design method for bridged-T coil (BTC) is proposed such that it can be made equivalent to two different transmission line sections at two different frequencies. In this way, on-chip dual-band branch-line coupler and dual-band power divider designs with very compact circuit sizes can be made possible through the use of BTCs. Specifically, the proposed 2.45/5.8-GHz dual-band branch-line coupler realized using the integrated passive device (IPD) process features a compact circuit size of only mm while the proposed 2.4/5.5-GHz dual-band power divider in IPD exhibits a very small circuit size of only mm. To the best of our knowledge, the proposed dual-band branch-line coupler is the smallest one ever reported while the circuit size of the proposed dual-band power divider is comparable to the smallest in the literature.
Autors: Wei-Ting Fang;En-Wei Chang;Yo-Shen Lin;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2018, volume: 66, issue:2, pages: 889 - 901
Publisher: IEEE
 
» Bridging the Gap: Dialogue Between Engineers & Social Scientists [From the Editor]
Abstract:
This unique issue seeks to bridge the gap between engineers & social scientists and encourage dialogue between electric power professionals and social scientists who provide key insights into our customer base. Our guest editors compiled five well-written articles that challenge the usual way most electrical power system professionals think about our industry. As summarized in the "Guest Editorial," the issue identifies key behavioral factors that must be considered by engineers and ways that we should respond to customer concerns. Papers from the issue are briefly summarized.
Autors: Michael Henderson;
Appeared in: IEEE Power and Energy Magazine
Publication date: Feb 2018, volume: 16, issue:1, pages: 4 - 6
Publisher: IEEE
 
» Broadband Cloaking Obtained Using HOBBIES Optimization [EM Progammer's Notebook]
Abstract:
In this article, we describe the notion of a cloak achieved by employing the usual composite dielectrics surrounding a metal cube, a concept that was first presented by Hwang and Chin [1]. Here, we use an optimization procedure to improve on their results and obtain a three-dimensional composite dielectric structure that can achieve a better broadband match than that of [1]. The two structures of interest are an empty metallic waveguide and a metal cube placed inside the same waveguide but surrounded by different-sized dielectric slabs so that the effect of the metal cube in the transmitted fields inside the waveguide will not be much different from the fields that would exist in an empty waveguide. The dimensions and properties of the simple dielectrics making up the different slabs inside the waveguide are optimized using an electromagnetic simulator called Higher Order Basis Based Integral Equation Solver (HOBBIES) [2] so that the waveguide will appear empty by looking at the nature of the transmitted fields from the waveguide loaded with a metallic cube but surrounded by some dielectrics.
Autors: Hongsik Moon;Tapan K. Sarkar;Magdalena Salazar Palma;
Appeared in: IEEE Antennas and Propagation Magazine
Publication date: Feb 2018, volume: 60, issue:1, pages: 112 - 117
Publisher: IEEE
 
» Broadband Continuous-Mode Doherty Power Amplifiers With Noninfinity Peaking Impedance
Abstract:
In this paper, a broadband continuous-mode Doherty power amplifier (CM-DPA) is realized taking advantage of the noninfinity output impedances of peaking stage. Specifically, the carrier PA of the designed DPA operates in a continuous class-J mode when the peaking PA is in the OFF-state, where the output impedance of the peaking PA has some influences on the carrier PA. When the peaking transistor is in the OFF-state, the load impedance variation of the carrier transistor versus noninfinity peaking impedance is presented in this contribution. The proposed method surmounts the back-off drain efficiency deterioration of DPAs at two side working bands through elaborately processing the noninfinity peaking impedance. This paper also presents a method to derive the required OFF-state output impedance of the peaking stage by the carrier PA in a symmetrical broadband DPA. A broadband CM-DPA working over 1.6–2.7 GHz (bandwidth of 51%) is designed and fabricated for interpreting our theories. The simulated load trajectory of the carrier transistor is in line with the design space of continuous class-J mode. Under continuous wave excitation, experimental results show the drain efficiencies of 46.5%–63.5% at 6-dB output back-off power levels and 56%–75.3% at peaking power levels. The maximum output power of this DPA is 43.8–45.2 dBm with a gain of 9.4–11.5 dB across the whole working band. Furthermore, a 20-MHz LTE modulated signal with a peak-to-average power ratio of 7.4 dB is also applied to the fabricated CM-DPA at 2.2 GHz. At an average output power of 37.5 dBm, measurement results show the adjacent channel power ratios of −30.2 and −50.1 dBc before and after digital predistortion, respectively.
Autors: Weimin Shi;Songbai He;Xiaoyu Zhu;Bin Song;Zhitao Zhu;Gideon Naah;Min Zhang;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2018, volume: 66, issue:2, pages: 1034 - 1046
Publisher: IEEE
 
» Broadband High-Energy All-Fiber Laser at 1.6 $mu$ m
Abstract:
A broadband high-energy all-fiber laser at 1.6- window with erbium-doped fiber mode locked by nonlinear polarization rotation technology is demonstrated. The direct output optical spectrum centered at 1.6 has a bandwidth of 52.4 nm. The fiber laser delivers a pulse energy of 3.9 nJ with 9.3-MHz repetition rate at 220-mW 976-nm pump power. Based on it, a wavelength-tunable optical source with a wavelength tuning range from 1.6 to 1.8 is demonstrated through soliton self-frequency shift. To satisfy much longer wavelength demands in some special application scenario, e.g., deep brain imaging with multi-photon microscopy, a chirped pulse amplifier was constructed to boost the pulse energy to 14 nJ, and the wavelength can be tuned from 1.6 to 1.94 with those amplified pulses. These fiber sources at the -band and a longer wavelength can explore a wider scope in deep biotissue imaging area for lower water absorption.
Autors: Jiqiang Kang;Cihang Kong;Pingping Feng;Xiaoming Wei;Zhi-Chao Luo;Edmund Y. Lam;Kenneth K. Y. Wong;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:4, pages: 311 - 314
Publisher: IEEE
 
» Broadband IF-Over-Fiber Transmission With Parallel IM/PM Transmitter Overcoming Dispersion-Induced RF Power Fading for High-Capacity Mobile Fronthaul Links
Abstract:
We demonstrate a broadband and long-distance intermediate frequency-over-fiber (IFoF) transmission scheme employing a transmitter composed of parallel intensity/phase (IM/PM) modulators with appropriate bandwidth allocations to IM and PM. Due to the proposed scheme, we can eliminate all the null frequencies caused by dispersion-induced RF power fading, which, in turn, enables us to significantly increase the available bandwidth. In addition, our system does not require any synchronization between IM and PM, which reduces complexity compared to conventional parallel transmitter architecture. We successfully transmitted 20 360 MHz filtered orthogonal-frequency-division-multiplexed signals corresponding to a common public radio interface equivalent data rate of 524.28 Gbps over a 30- and 40-km single-mode fiber satisfying the 8% threshold for the error-vector magnitude values for all the subcarriers. These results show that our proposed IFoF transmission scheme is scalable to long-distance mobile fronthaul links for 5G and beyond.
Autors: Shota Ishimura;Byung Gon Kim;Kazuki Tanaka;Kosuke Nishimura;Hoon Kim;Yun C. Chung;Masatoshi Suzuki;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 9
Publisher: IEEE
 
» Broadband Photonic Microwave Signal Processor With Frequency Up/Down Conversion and Phase Shifting Capability
Abstract:
A new dual-function photonic microwave signal processing structure that has the ability to realize both frequency up/down conversion and RF/IF phase shifting, is presented. In the proposed signal processor, a dual-polarization dual-parallel Mach Zehnder modulator (DP-DPMZM) is used to generate an orthogonally polarized single RF/IF signal and local oscillator (LO) modulation sideband without an optical carrier. The optical phase difference between the two sidebands can be controlled by controlling a DC voltage applied to a LiNbO3 electro-optic phase modulator that is connected after the DP-DPMZM. Beating between the two sidebands at a photodetector generates an RF/IF signal with a phase equal to the optical phase difference between the IF/RF signal and LO sidebands. The dual-function photonic microwave signal processor has a wide bandwidth and does not require a precise control of the laser wavelength. Experimental results demonstrate that a flat >-3 dB down/up conversion efficiency is achieved for an RF signal from 3.5 to 26.5 GHz and for an IF signal from 0.5 to 3 GHz, and a full 360° continuous phase shift of the output IF/RF signal.
Autors: Tao Li;Erwin Hoi Wing Chan;Xudong Wang;Xinhuan Feng;Bai-Ou Guan;Jianping Yao;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 12
Publisher: IEEE
 
» BTI Analysis Tool—Modeling of NBTI DC, AC Stress and Recovery Time Kinetics, Nitrogen Impact, and EOL Estimation
Abstract:
A comprehensive modeling framework is presented to predict the time kinetics of negative bias temperature instability stress and recovery during and after dc and ac stresses and also during mixed dc–ac stress. The model uses uncorrelated contributions from the generation of interface and bulk traps and hole trapping in preexisting bulk traps. Ultrafast measured data at different stresses and recovery biases, temperature, duty cycle and frequency, as well as arbitrary time segments with dynamically varying voltage, frequency, and activity are predicted. The role of nitrogen in the gate insulator is explained. End-of-life degradation is determined under dc and ac use conditions.
Autors: Narendra Parihar;Nilesh Goel;Subhadeep Mukhopadhyay;Souvik Mahapatra;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2018, volume: 65, issue:2, pages: 392 - 403
Publisher: IEEE
 
» Build a nixie-S style clock without the fuss
Abstract:
STANLEY KUBRICK'S 1968 SCIENCE FICTION FILM 2001: A Space Odyssey still stands up pretty well. But there's a telling anachronism in the scene where scientists visit a monolith that's been uncovered on the moon. On their lunar shuttle's control panel, there are numerical indicator lights clearly made with cold-cathode displays, also known as Nixie tubes. This technology was in vogue during the mid-1950s but fell out of favor in the 1970s. Nixie tubes still enjoy a following among enthusiasts of retro technology. I've sometimes been tempted to build a Nixie-tube clock, but the difficulties and expense always put me off. It's hard even to purchase Nixie tubes at this point—especially larger ones-and they require high-voltage driver circuits, which are inherently dangerous. So I was delighted when I stumbled on something designed to mimic the appearance of Nixie tubes without the complications-something its designer calls a "Lixie display."
Autors: David Schneider;
Appeared in: IEEE Spectrum
Publication date: Feb 2018, volume: 55, issue:2, pages: 19 - 20
Publisher: IEEE
 
» Cache-Enabled Physical Layer Security for Video Streaming in Backhaul-Limited Cellular Networks
Abstract:
In this paper, we propose a novel wireless caching scheme to enhance the physical layer security of video streaming in cellular networks with limited backhaul capacity. By proactively sharing video data across a subset of base stations (BSs) through both caching and backhaul loading, secure cooperative joint transmission of several BSs can be dynamically enabled in accordance with the cache status, the channel conditions, and the backhaul capacity. Assuming imperfect channel state information (CSI) at the transmitters, we formulate a two-stage non-convex mixed-integer robust optimization problem for minimizing the total transmit power while providing the quality of service and guaranteeing communication secrecy during video delivery, where the caching and the cooperative transmission policy are optimized in an offline video caching stage and an online video delivery stage, respectively. Although the formulated optimization problem turns out to be NP-hard, low-complexity polynomial-time algorithms, whose solutions are globally optimal under certain conditions, are proposed for cache training and video delivery control. Caching is shown to be beneficial as it reduces the data sharing overhead imposed on the capacity-constrained backhaul links, introduces additional secure degrees of freedom, and enables a power-efficient communication system design. Simulation results confirm that the proposed caching scheme achieves simultaneously a low secrecy outage probability and a high power efficiency. Furthermore, due to the proposed robust optimization, the performance loss caused by imperfect CSI knowledge can be significantly reduced when the cache capacity becomes large.
Autors: Lin Xiang;Derrick Wing Kwan Ng;Robert Schober;Vincent W. S. Wong;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Feb 2018, volume: 17, issue:2, pages: 736 - 751
Publisher: IEEE
 
» Caching Meets Millimeter Wave Communications for Enhanced Mobility Management in 5G Networks
Abstract:
One of the most promising approaches to overcoming the uncertainty of millimeter wave (mm-wave) communications is to deploy dual-mode small base stations (SBSs) that integrate both mm-wave and microwave () frequencies. In this paper, a novel approach to analyzing and managing mobility in joint mmwave– networks is proposed. The proposed approach leverages device-level caching along with the capabilities of dual-mode SBSs to minimize handover failures and reduce inter-frequency measurement energy consumption. First, fundamental results on the caching capabilities are derived for the proposed dual-mode network scenario. Second, the impact of caching on the number of handovers (HOs), energy consumption, and the average handover failure (HOF) is analyzed. Then, the proposed cache-enabled mobility management problem is formulated as a dynamic matching game between mobile user equipments (MUEs) and SBSs. The goal of this game is to find a distributed HO mechanism that, under network constraints on HOFs and limited cache sizes, allows each MUE to choose between: 1) executing an HO to a target SBS; 2) being connected to the macrocell base station; or 3) perform a transparent HO by using the cached content. To solve this dynamic matching problem, a novel algorithm is proposed and its convergence to a two-sided dynamically stable HO policy for MUEs and target SBSs is proved. Numerical results corroborate the analytical derivations and show that the proposed solution will significantly reduce both the HOF and energy consumption of MUEs, resulting in an enhanced mobility management for heterogeneous wireless networks with mm-wave capabilities.
Autors: Omid Semiari;Walid Saad;Mehdi Bennis;Behrouz Maham;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Feb 2018, volume: 17, issue:2, pages: 779 - 793
Publisher: IEEE
 
» Calculating the Expected Time to Eradicate HIV-1 Using a Markov Chain
Abstract:
In this study, the expected time required to eradicate HIV-1 completely was found as the conditional absorbing time in a finite state space continuous-time Markov chain model. The Markov chain has two absorbing states: one corresponds to HIV eradication and another representing the possible disaster. This method allowed us to calculate the expected eradication time by solving systems of linear equations. To overcome the challenge of huge dimension of the problem, we applied a novel stop and resume technique. This technique also helped to stop the numerical computation whenever we wanted and continue later from that point until the final result was obtained. Our numerical study showed the dependence of the expected eradication time of HIV on the half-life of the latently infected cells and there agreed with the previous studies. The study predicted that when the half-life of the latent cells varied from 4.6 to 60 months, it took a mean 4.97 to 31.04 years with a corresponding standard deviation of 0.64 to 3.99 years to eradicate the latent cell reservoir. It also revealed the crucial dependence of eradication time on the initial number of latently infected cells.
Autors: Narayanan C. Viswanath;
Appeared in: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Publication date: Feb 2018, volume: 15, issue:1, pages: 60 - 67
Publisher: IEEE
 
» Calibration Algorithm for Cross-Track Infrared Sounder Full Spectral Resolution Measurements
Abstract:
The cross-track infrared sounder has been operated in the full spectral resolution (FSR) mode since December 4, 2014. To provide the FSR radiance spectra with a spectral resolution of 0.625 cm−1 for all the three bands, a new calibration algorithm has been developed and implemented for operational uses. The algorithm is an improvement over the previous algorithm that had been operationally used until March 2017. Major changes include the calibration equation, self-apodization correction and resampling matrices, and calibration filter. Compared to the previous algorithm, the improvement reduces the calibration inconsistencies among the nine fields of view and between the forward and reverse interferometer sweep directions by up to 0.5 K, and the differences between observed and simulated spectra by up to 0.4 K.
Autors: Yong Han;Yong Chen;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2018, volume: 56, issue:2, pages: 1008 - 1016
Publisher: IEEE
 
» Calling Inspector Gadget [Microwave Surfing]
Abstract:
Unless you were away earlier this year on an intergalactic mission, you probably picked up the heavy media buzz around the claim [1] made by an “important government source”: There was an article this week that talked about how you can surveil someone through their phones, through their . . . certainly through their television sets, any number of different ways. And microwaves that turn into cameras, et cetera. So we know that that is just a fact of modern life. So: is it really a fact of modern life that microwaves can spy on you? It depends on the meaning of microwaves. According to the Merriam-Webster Online Dictionary [2], the word means either “a comparatively short electromagnetic wave; especially: one between about one millimeter and one meter in wavelength” or a “microwave oven.”
Autors: Rajeev Bansal;
Appeared in: IEEE Microwave Magazine
Publication date: Feb 2018, volume: 19, issue:1, pages: 12 - 130
Publisher: IEEE
 
» Capacity Optimization for Resource Pooling in Virtualized Data Centers with Composable Systems
Abstract:
Recent research trends exhibit a growing imbalance between the demands of tenants’ software applications and the provisioning of hardware resources. Misalignment of demand and supply gradually hinders workloads from being efficiently mapped to fixed-sized server nodes in traditional data centers. The incurred resource holes not only lower infrastructure utilization but also cripple the capability of a data center for hosting large-sized workloads. This deficiency motivates the development of a new rack-wide architecture referred to as the composable system . The composable system transforms traditional server racks of static capacity into a dynamic compute platform. Specifically, this novel architecture aims to link up all compute components that are traditionally distributed on traditional server boards, such as central processing unit (CPU), random access memory (RAM), storage devices, and other application-specific processors. By doing so, a logically giant compute platform is created and this platform is more resistant against the variety of workload demands by breaking the resource boundaries among traditional server boards. In this paper, we introduce the concepts of this reconfigurable architecture and design a framework of the composable system for cloud data centers. We then develop mathematical models to describe the resource usage patterns on this platform and enumerate some types of workloads that commonly appear in data centers. From the simulations, we show that the composable system sustains nearly up to 1.6 times stronger workload intensity than that of traditional systems and it is insensitive to the distribution of workload demands. This demonstrates that this composable system is indeed an effective solution to support cloud data center services.
Autors: An-Dee Lin;Chung-Sheng Li;Wanjiun Liao;Hubertus Franke;
Appeared in: IEEE Transactions on Parallel and Distributed Systems
Publication date: Feb 2018, volume: 29, issue:2, pages: 324 - 337
Publisher: IEEE
 
» Car Detection in Aerial Images of Dense Urban Areas
Abstract:
With the ever-increasing demand in the analysis and understanding of aerial images in order to remotely recognize targets, this paper introduces a robust system for the detection and localization of cars in images captured by air vehicles and satellites. The system adopts a sliding-window approach. It compromises a window-evaluation and a window-classification subsystems. The performance of the proposed framework was evaluated on the Vaihingen dataset. Results demonstrate its superiority to the state of the art.
Autors: Mohamed ElMikaty;Tania Stathaki;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 51 - 63
Publisher: IEEE
 
» Carrier Mobility Enhancement by Applying Back-Gate Bias in Ge-on-Insulator MOSFETs
Abstract:
In this letter, we comprehensively study the carriers’ mobility and the effect of back-gate bias () in Ge-on-insulator (GeOI) MOSFETs with various working modes, including accumulation mode (AM) nMOSFET, inversion mode (IM) nMOSFET, AM pMOSFET, and IM pMOSFET. The results show that the AM nMOSFETs and pMOSFETs have higher drain currents and carriers’ mobility. The electron mobility increases under positive and decreases under negative . While the hole mobility has the opposite dependence. The carriers’ mobility of AM MOSFETs is proved to benefit more from due to the increase of carriers’ densities. The peak mobility enhancements of more than 100% for holes and 35% for electrons are achieved in GeOI MOSFETs by applying .
Autors: Wangran Wu;Heng Wu;Jingyun Zhang;Mengwei Si;Yi Zhao;Peide D. Ye;
Appeared in: IEEE Electron Device Letters
Publication date: Feb 2018, volume: 39, issue:2, pages: 176 - 179
Publisher: IEEE
 
» Causality Countermeasures for Anomaly Detection in Cyber-Physical Systems
Abstract:
The problem of attack detection in cyber-physical systems is considered in this paper. Transfer-entropy-based causality countermeasures are introduced for both sensor measurements and innovation sequences, which can be evaluated in a data-driven fashion without relying on a model of the underlying dynamic system. The relationships between the countermeasures and the system parameters as well as the noise statistics are investigated, based on which conditions that guarantee the time convergence of the countermeasures are obtained. The effectiveness of the transfer entropy countermeasures in attack detection is evaluated via theoretical analysis, numerical demonstrations, as well as comparative simulations with classical detectors. Four types of attacks are considered: denial-of-service, replay, innovation-based deception, and data injection attacks. Abnormal behavior of the transfer entropy can be observed after the occurrence of each of these attacks.
Autors: Dawei Shi;Ziyang Guo;Karl Henrik Johansson;Ling Shi;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Feb 2018, volume: 63, issue:2, pages: 386 - 401
Publisher: IEEE
 
» CCL: Cross-modal Correlation Learning With Multigrained Fusion by Hierarchical Network
Abstract:
Cross-modal retrieval has become a highlighted research topic for retrieval across multimedia data such as image and text. A two-stage learning framework is widely adopted by most existing methods based on deep neural network (DNN): The first learning stage is to generate separate representation for each modality and the second learning stage is to get the cross-modal common representation. However the existing methods have three limitations: 1) In the first learning stage they only model intramodality correlation but ignore intermodality correlation with rich complementary context. 2) In the second learning stage they only adopt shallow networks with single-loss regularization but ignore the intrinsic relevance of intramodality and intermodality correlation. 3) Only original instances are considered while the complementary fine-grained clues provided by their patches are ignored. For addressing the above problems this paper proposes a cross-modal correlation learning (CCL) approach with multigrained fusion by hierarchical network and the contributions are as follows: 1) In the first learning stage CCL exploits multilevel association with joint optimization to preserve the complementary context from intramodality and intermodality correlation simultaneously. 2) In the second learning stage a multitask learning strategy is designed to adaptively balance the intramodality semantic category constraints and intermodality pairwise similarity constraints. 3) CCL adopts multigrained modeling which fuses the coarse-grained instances and fine-grained patches to make cross-modal correlation more precise. Comparing with 13 state-of-the-art methods on 6 widely-used cross-modal datasets the experimental results show our CCL approach achieves the best performance.
Autors: Yuxin Peng;Jinwei Qi;Xin Huang;Yuxin Yuan;
Appeared in: IEEE Transactions on Multimedia
Publication date: Feb 2018, volume: 20, issue:2, pages: 405 - 420
Publisher: IEEE
 
» Ceramics for the Future: Advanced Millimeter-Wave Multilayer Multichip Module Integration and Packaging
Abstract:
The advantages of higher-frequency operation, such as wider bandwidth and finer spatial and temporal resolution, have led to increased interest in the use of millimeter-waves (mmWs) in both commercial and military applications-covering, in particular, areas ranging from high-speed wireless communication (including wireless local area networking, wireless gigabit communication, sensor networks, and fifth-generation systems) to space science to security [1]-[5]. For biological and health applications, mmW imaging offers a superior, safer, and lower-cost alternative to conventional techniques [6], [7].
Autors: Kamal K. Samanta;
Appeared in: IEEE Microwave Magazine
Publication date: Feb 2018, volume: 19, issue:1, pages: 22 - 35
Publisher: IEEE
 
» Certificateless Searchable Public Key Encryption Scheme for Industrial Internet of Things
Abstract:
With the widespread adoption of Internet of Things and cloud computing in different industry sectors, an increasing number of individuals or organizations are outsourcing their Industrial Internet of Things (IIoT) data in the cloud server to achieve cost saving and collaboration (e.g., data sharing). However, in this environment, preserving the privacy of data remains a key challenge and inhibiting factor to an even wider adoption of IIoT in the cloud environment. To mitigate these issues, in this paper, we design a new secure channel-free certificateless searchable public key encryption with multiple keywords scheme for IIoT deployment. We then demonstrate the security of the scheme in the random oracle model against two types of adversaries, where one adversary is given the power to choose a random public key instead of any user's public key and another adversary is allowed to learn the system master key. In the presence of these types of adversaries, we evaluate the performance of the proposed scheme and demonstrate that it achieves (computational) efficiency with low communication cost.
Autors: Mimi Ma;Debiao He;Neeraj Kumar;Kim-Kwang Raymond Choo;Jianhua Chen;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2018, volume: 14, issue:2, pages: 759 - 767
Publisher: IEEE
 
» Changes Impacting Our Publications [From the Editor's Desk]
Abstract:
Discusses the IEEE PSPB rules regarding the republication of papers in IEEE Xplore and assesses its impact on IAS publications.
Autors: Lanny Floyd;
Appeared in: IEEE Industry Applications Magazine
Publication date: Feb 2018, volume: 24, issue:1, pages: 3 - 5
Publisher: IEEE
 
» Changing Household Energy Usage: The Downsides of Incentives and How to Overcome Them
Abstract:
To combat climate change, the Intergovernmental Panel for Climate Change (IPCC) calculated that greenhouse gas emissions in the energy domain should be reduced by 90%, compared to 2010 emissions, between the years 2040 and 2070. In Europe, residential households consume about a quarter of total energy used (excluding the energy that is embodied in products). To contribute to the carbon emission reduction targets set by the IPCC , households need to reduce their fossilenergy use.
Autors: Ellen van der Werff;John Thogersen;Wandi Bruine de Bruin;
Appeared in: IEEE Power and Energy Magazine
Publication date: Feb 2018, volume: 16, issue:1, pages: 42 - 48
Publisher: IEEE
 
» Changing the Electrical Safety Culture
Abstract:
This paper examines what it takes to improve the electrical safety culture in an organization. First, the components of a culture are examined and how any culture comes to be the norm is reviewed. Second, examples are given on how culture has already changed significantly by contrasting past and present work practices in electrical safety. Third, suggestions for concrete ways to make future improvements in electrical safety cultures are provided. A fundamental argument in this paper is that culture represents the sum total of what is commonly acceptable without examination. The culture is also driven by everyday observation and experience. In order to change the culture, there must be a redefinition of what is acceptable, followed by visible changes that everyone can experience and observe. Management owns the resulting culture, whether good or bad, because it sets standards for what behaviors are tolerable and acceptable. Therefore, the future of electrical safety will depend on how well management understands the risk and consequences of electrical work, and their responsibility in shaping and owning electrical safety policies and practices. Key elements addressed in this paper include management ownership of the electrical safety culture, busting the myth of “overcompliance,” integrating cultural drivers into an overall electrical safety program, and addressing the more difficult aspects of human performance in a fair manner.
Autors: Daryld Ray Crow;Danny P. Liggett;Mark A. Scott;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 808 - 814
Publisher: IEEE
 
» Channel Capacity of Wavelength Division Multiplexing-Based Brillouin Optical Time Domain Sensors
Abstract:
We propose and demonstrate a novel WDM-based Brillouin optical time domain analysis (BOTDA) sensor using Brillouin loss configuration, and theoretically analyze channel capacity of WDM-based brillouin optical time domain reflectometry (BOTDR) and BOTDA sensors by considering the fiber dispersion and nonlinear effects in sensing fibers. A three-wavelength WDM-based BOTDA senor is experimentally validated in the distributed temperature measurement of a 23-km-long standard telecom fiber (SMF-28), demonstrating an electrical signal-to-noise ratio enhancement of 9.2 dB. The numerical calculation results of the channel capacity of WDM-based Brillouin optical time domain sensors show that, when compared with the conventional single-wavelength BOTDR and BOTDA sensors, 11-wavelength BOTDR and BOTDA sensor using large effective area fiber can respectively achieve 8.4 and 20.8 dB signal-noise-ratio improvement (SNRI), and 7-wavelength BOTDR and BOTDA sensor using SMF-28 can respectively achieve 7.2 B and 16.9 dB SNRI without evident spatial resolution degradation and nonlinear impairment.
Autors: Zelin Zhang;Yuangang Lu;Yunqin Zhao;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 15
Publisher: IEEE
 
» Channel Estimation for mmWave MIMO With Transmitter Hardware Impairments
Abstract:
This letter considers the problem of channel estimation for millimeter wave (mmWave) multiple-input multiple-output systems under a transmitter impairments model. Specifically, taking the transmitter hardware impairments into account, the performance of conventional pilots-based channel estimation scheme will be degraded due to the destroyed training pilots. By exploiting the sparsity of mmWave channel in the angular domain, a new channel estimation algorithm based on the Bayesian compressive sensing (BCS) and least square estimation (LSE) is proposed. First, the expectation maximization algorithm is presented to solve the BCS problem, and the refined measurement matrix and the support of the channel vector are obtained. Next, the channel gain coefficients are estimated by using the LSE. Simulation results show that the proposed algorithm can achieve better performance compared with the conventional BCS and orthogonal matching pursuit algorithm.
Autors: Yue Wu;Yuantao Gu;Zhaocheng Wang;
Appeared in: IEEE Communications Letters
Publication date: Feb 2018, volume: 22, issue:2, pages: 320 - 323
Publisher: IEEE
 
» Chaotic Constellation Mapping for Physical-Layer Data Encryption in OFDM-PON
Abstract:
A physical-layer encryption scheme is proposed and experimentally demonstrated in orthogonal frequency division multiplexing passive optical network (OFDM-PON). In the proposed multifold encryption scheme, quadratic-amplitude modulation (QAM) symbols are scrambled and distributed onto the complex plane independently. The dynamic parameters of constellation shifting are generated by a 3-D hyper digital chaos, in which a key space of ~10162 is created to enhance the security level of OFDM data encryption during transmission. An encrypted data transmission of 9.4-Gb/s, 16-QAM optical OFDM signals is successfully demonstrated over 20-km standard single-mode fiber.
Autors: Amber Sultan;Xuelin Yang;Adnan A. E. Hajomer;Weisheng Hu;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:4, pages: 339 - 342
Publisher: IEEE
 
» Characteristic Impedance Control for Branch-Line Coupler Design
Abstract:
This letter presents a new approach to control impedance for branch-line coupler (BLC) design. With the proposed method, the highest impedance of the two-section BLC can be set to a realistic value (below ), so that it can be implemented with ordinary planar technology. The measured results are compared with the simulated results to validate the proposed theory and design approach.
Autors: Qiuyi Wu;Yimin Yang;Ying Wang;Xiaowei Shi;Ming Yu;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Feb 2018, volume: 28, issue:2, pages: 123 - 125
Publisher: IEEE
 
» Characteristic Mode Assisted Placement of Antennas for the Isolation Enhancement
Abstract:
In this letter, the isolation between onboard antennas is investigated using characteristic mode analysis, which provides an intuitive insight for the antenna placement on large platforms. An analytical expression of the relationship between the platform modal excitation coefficient and the platform modal charge is derived under the condition of a coaxial feeding mechanism. It is revealed that the deployment position that leads to a maximum isolation is indicated by the platform modal charge. Based on this finding, a simple and efficient method for antenna placement on aircraft-like platforms is developed to enhance the isolation. Two examples with vertically polarized blade antennas are presented, in which two or three blade antennas can be deployed on the platforms. Both the numerical and experimental results show that the isolation is increased remarkably by the proposed method.
Autors: Donglin Su;Zhao Yang;Qi Wu;
Appeared in: IEEE Antennas and Wireless Propagation Letters
Publication date: Feb 2018, volume: 17, issue:2, pages: 251 - 254
Publisher: IEEE
 
» Characteristics and Performances of a 100-W Hall Thruster for Microspacecraft
Abstract:
In this paper, we examine the characteristics of the ISCT100 thruster, a miniature xenon-fueled 100-W permanent magnet Hall thruster (HT) suited for microspacecraft propulsion. The impact of the thruster design upon discharge behavior, ion beam properties, and performances is examined as for two discharge channel geometries as well as two values of the magnetic field strength. Thrust, specific impulse, and efficiency obtained between 50 and 200 W are compared with the ones of other low-power HTs.
Autors: Stéphane Mazouffre;Lou Grimaud;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Feb 2018, volume: 46, issue:2, pages: 330 - 337
Publisher: IEEE
 
» Characteristics of Large Antennas with Radomes [Antenna Applications Corner]
Abstract:
Radomes for large ground antennas used in satellite communications have been analyzed extensively in the past, but little work related to the practical evaluation of radio-frequency (RF) performance has been reported. This article summarizes the results of observations conducted on three different kinds of antennas with radomes operating at the X and Ka frequencies.
Autors: Roland William Schwerdtfeger;
Appeared in: IEEE Antennas and Propagation Magazine
Publication date: Feb 2018, volume: 60, issue:1, pages: 94 - 103
Publisher: IEEE
 
» Characteristics of Recessed-Gate TFETs With Line Tunneling
Abstract:
In this paper, we propose a recessed-gate tunneling field-effect transistor (TFET) to improve the on current of TFETs by increasing the tunnel area with line tunneling. We investigate the effects of the recessed-body thickness and the doping level on the device performance. For optimal device structures, our proposed n-TFET reaches A/ of on current and ON/ OFF current ratio. A minimum subthreshold swing SS mV/dec and an average swing SS mV/dec over seven orders of drain current are achieved. In addition, complementary TFET inverters show good noise margins of mV (38.5 % ) and NM mV (32.5 % ) and also a high voltage gain even at V.
Autors: Jyi-Tsong Lin;Tzu-Chi Wang;Wei-Han Lee;Chih-Ting Yeh;Stefan Glass;Qing-Tai Zhao;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2018, volume: 65, issue:2, pages: 769 - 775
Publisher: IEEE
 
» Characterization and Modeling of Tissue Thermal Conductivity During an Electrosurgical Joining Process
Abstract:
Electrosurgical vessel joining is commonly performed in surgical procedures to maintain hemostasis. This process requires elevated temperature to denature the tissue and while compression is applied, the tissue can be joined together. The elevated temperature can cause thermal damages to the surrounding tissues. In order to minimize these damages, it is critical to understand how the tissue properties change and how that affects the thermal spread. The purpose of this study is to investigate the changes of tissue thermal conductivity and how the changes correlate to thermal dose during the joining process. We propose a hybrid method combining experimental measurement with inverse heat transfer analysis to determine thermal conductivity of thin tissue sample. Porcine aorta arterial tissues were used to investigate tissue thermal conductivity with variable thermal dose. Different joining times were used to create different amounts of thermal dose. A 36% decrease in tissue thermal conductivity was found when the thermal dose reaches the threshold for second-degree burn. When thermal dose is beyond the threshold of third-degree burn, the tissue thermal conductivity does not decrease significantly. A regression model was also developed and can be used to predict tissue thermal conductivity based on the thermal dose.
Autors: Che-Hao Yang;Wei Li;Roland K. Chen;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Feb 2018, volume: 65, issue:2, pages: 365 - 370
Publisher: IEEE
 
» Characterization of a Terbium-Activated Gadolinium Oxysulfide Plastic Optical Fiber Sensor in Photons and Protons
Abstract:
A characterization study was carried out to determine if a novel, millimeter sized Terbium-activated Gadolinium Oxysulfide optical fibre detector has potential for future use in proton dosimetry. Preliminary studies employed a Theratronics Theratron 780C Cobalt-60 unit and were used to determine nominal dose response, field size response and Čerenkov contributions in 1.25-MeV gamma radiation. More extensive testing was done using 74 MeV-protons produced in the TRIUMF 500-MeV cyclotron facility examining raw Bragg peak, spread out Bragg peak, dose response, and Čerenkov signal. The detector was low-cost and easily assembled; it showed excellent sensitivity, signal to noise ratio, and reproducibility. Quenching at high linear energy transfer was severe. Additional investigations are needed to further explore Čerenkov-only depth-dose curves, signal detection at the extreme distal end of the Bragg peak, and possible sensitivity to neutrons.
Autors: Crystal Penner;Cornelia Hoehr;Sinead O’Keeffe;Peter Woulfe;Cheryl Duzenli;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1513 - 1519
Publisher: IEEE
 
» Characterization of Intermodulation Distortion in Reconfigurable Liquid Metal Antennas
Abstract:
The intermodulation distortion produced by passive and tunable liquid metal (LM) antennas is investigated. Four kinds of monopoles, including a passive copper monopole, a varactor-tuned copper monopole, a passive LM monopole, and a tunable LM monopole using electrochemically controlled capillarity (ECC), are compared for their linearity and power-handling capabilities. Linearity is assessed using a two-tone distortion test, in which two fundamental tones close in frequency result in third-order intermodulation tones at frequencies above and below the original tones separated by the frequency difference. The passive LM monopole has comparable linearity to the passive copper monopole, while the linearity of the ECC-tuned LM monopole is at least 40 dB better than that of the active varactor monopole. The reconfigurable LM antenna also handles higher power (31 dBm) before failure than does the active varactor-tuned antenna (24 dBm).
Autors: Meng Wang;Ian M. Kilgore;Michael B. Steer;Jacob J. Adams;
Appeared in: IEEE Antennas and Wireless Propagation Letters
Publication date: Feb 2018, volume: 17, issue:2, pages: 279 - 282
Publisher: IEEE
 
» Characterizations of Enhancement-Mode Double Heterostructure GaN HEMTs With Gate Field Plates
Abstract:
With the purpose to increase the threshold voltage of the enhancement mode GaN high-electron mobility transistors, we fabricated devices with gate field plates on the p-GaN/AlGaN/GaN/AlGaN double heterostructures. We observed an existence of a subthreshold region from the current–voltage transfer curves. The threshold voltage of the device extracted based on linear extrapolation method is much higher than that of a typical device without a gate field plate. We investigated electrical properties based on carrier distributions with the influence of gate electric field at different channel regions.
Autors: Chun-Hsun Lee;Wei-Ren Lin;Yu-Hsuan Lee;Jian-jang Huang;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2018, volume: 65, issue:2, pages: 488 - 492
Publisher: IEEE
 
» Characterizing Antennas in the Time and Frequency Domains [Education Corner]
Abstract:
The antenna definitions standard [1] currently has no terms that describe antenna performance in the time domain, possibly due to the complexity of the equations. However, if the antenna equations are expressed using quantities related to the square root of power, then simple expressions are obtained that are valid in both the frequency and time domains. This leads to a number of new terms that should be considered for inclusion in the next revision of the standard. Doing so would provide a common language for discussing antenna performance in the time domain. It would also add phase information to common frequency-domain terms, such as antenna gain and radar cross section.
Autors: Everett G. Farr;
Appeared in: IEEE Antennas and Propagation Magazine
Publication date: Feb 2018, volume: 60, issue:1, pages: 106 - 110
Publisher: IEEE
 
» Characterizing Engineering Learners’ Preferences for Active and Passive Learning Methods
Abstract:
This paper studies electrical engineering learners’ preferences for learning methods with various degrees of activity. Less active learning methods such as homework and peer reviews are investigated, as well as a newly introduced very active (constructive) learning method called “slectures,” and some others. The results suggest that graduate students’ perception of the usefulness of the activity increases with its level of activity. For undergraduate students, an increased perception of the usefulness of the activity was observed for lightly active but structured learning methods. Group-based analysis focusing on two types of learners, defined as “instructor-dependent” and “instructor-independent” according to their perception of the usefulness of the classroom lectures, was also performed. The results suggest that instructor-independent learners may benefit more from active learning methods than instructor-dependent learners. For example, instructor-independent undergraduate learners were found to perceive the homework assignment as being more useful than the lectures. Such a preference was not seen in the average group data. In fact, no learning method was found to be perceived as more useful than the lectures, on average. Thus this paper illustrates the pertinence of group-based data analysis.
Autors: Alejandra J. Magana;Camilo Vieira;Mireille Boutin;
Appeared in: IEEE Transactions on Education
Publication date: Feb 2018, volume: 61, issue:1, pages: 46 - 54
Publisher: IEEE
 
» Characterizing Privacy Risks of Mobile Apps with Sensitivity Analysis
Abstract:
Given the emerging concerns over app privacy-related risks, major app distribution providers (e.g., Microsoft) have been exploring approaches to help end users to make informed decision before installation. This is different from existing approaches of simply trusting users to make the right decision. We build on the direction of risk rating as the way to communicate app-specific privacy risks to end users. To this end, we propose to use sensitivity analysis to infer whether an app requests sensitive on-device resources/data that are not required for its expected functionality. Our system, Privet, addresses challenges in efficiently achieving test coverage and automated privacy risk assessment. Finally, we evaluate Privet with 1,000 Android apps released in the wild.
Autors: Li Lyna Zhang;Chieh-Jan Mike Liang;Zhao Lucis Li;Yunxin Liu;Feng Zhao;Enhong Chen;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Feb 2018, volume: 17, issue:2, pages: 279 - 292
Publisher: IEEE
 

Publication archives by date

  2018:   January     February     March     April     May     June     July     August     September     October     November     December    

  2017:   January     February     March     April     May     June     July     August     September     October     November     December    

  2016:   January     February     March     April     May     June     July     August     September     October     November     December    

  2015:   January     February     March     April     May     June     July     August     September     October     November     December    

  2014:   January     February     March     April     May     June     July     August     September     October     November     December    

  2013:   January     February     March     April     May     June     July     August     September     October     November     December    

  2012:   January     February     March     April     May     June     July     August     September     October     November     December    

  2011:   January     February     March     April     May     June     July     August     September     October     November     December    

  2010:   January     February     March     April     May     June     July     August     September     October     November     December    

  2009:   January     February     March     April     May     June     July     August     September     October     November     December    

 
0-C     D-L     M-R     S-Z