#### Electrical and Electronics Engineering publications abstract of: 10-2017 sorted by title, page: 7

» Demonstration of a Novel Technique for Non-Intrusive In-Band OSNR Derivation Using Flexible Rate Optical Transponders Over a Live 727 km Flexible Grid Optical Link
 Abstract:In high speed optical transmission networks, OSNR is the key optical performance parameter. We propose a novel technique for non-intrusive in-band OSNR derivation based on real-time pre-FEC bit error rate (BER) measurement from optical transponders, which exploits pre-measured and calibrated pre-FEC BER versus OSNR curves and multiple modulation formats to ensure accurate OSNR derivation over a wide range. We report a successful field trial of this novel in-band OSNR technique, in which we have demonstrated and verified the accurate OSNR derivation over both a 359 km field trial link and a live 727 km flexible grid optical link using 64 GBaud flexible rate optical transponders with modulation formats 100G DP-QPSK, 200G DP-16QAM, and 200G DP–QPSK. Compared with standard signal “on” and “off” measurement, an OSNR accuracy within ±1 dB was achieved for all three modulation formats. We also investigated the impact of fiber nonlinearity at different signal powers on the accuracy of this technique. It is shown that this novel technique provides reliable and accurate OSNR derivation for the optical signals operating in normal power regime making it suitable for practical network applications. Autors: Yu Rong Zhou;Kevin Smith;John Weatherhead;Paul Weir;Andrew Lord;Jingxin Chen;Weiwei Pan;Daniel Tanasoiu;Shipeng Wu; Appeared in: Journal of Lightwave Technology Publication date: Oct 2017, volume: 35, issue:20, pages: 4399 - 4405 Publisher: IEEE
» DENA: A Configurable Microarchitecture and Design Flow for Biomedical DNA-Based Logic Design
 Abstract:DNA is known as the building block for storing the life codes and transferring the genetic features through the generations. However, it is found that DNA strands can be used for a new type of computation that opens fascinating horizons in computational medicine. Significant contributions are addressed on design of DNA-based logic gates for medical and computational applications but there are serious challenges for designing the medium and large-scale DNA circuits. In this paper, a new microarchitecture and corresponding design flow is proposed to facilitate the design of multistage large-scale DNA logic systems. Feasibility and efficiency of the proposed microarchitecture are evaluated by implementing a full adder and, then, its cascadability is determined by implementing a multistage 8-bit adder. Simulation results show the highlight features of the proposed design style and microarchitecture in terms of the scalability, implementation cost, and signal integrity of the DNA-based logic system compared to the traditional approaches. Autors: Zohre Beiki;Ali Jahanian; Appeared in: IEEE Transactions on Biomedical Circuits and Systems Publication date: Oct 2017, volume: 11, issue:5, pages: 1077 - 1086 Publisher: IEEE
» Depth Estimation From Light Field by Accumulating Binary Maps Based on Foreground–Background Separation
 Abstract:A three-dimensional (3-D) scene can be separated into two regions: foreground and background, which are regions in front of and behind the focused plane, respectively. From the 4-D light field, this paper proposes a depth estimation method by accumulating binary maps, which are computed by the foreground–background separation with light field reparameterization. In the proposed foreground–background separation, an optical phenomenon is used where bundles of rays from the background are flipped on their conjugate planes. Using the Lambertian assumption and gradient constraint, the foreground and background of a scene can be converted to a binary map by voting the gradient signs in every angular patch. Using light field reparameterization, the disparity map can be obtained by accumulating the binary maps. Finding the extremum index in the existing methods corresponds to finding the zero crossing index in the proposed method. By accumulating the binary maps, the proposed method has an advantage on the computational efficiency in terms of memory usage, and can use various reparameterization strategies suitable for applications. Experimental results with synthetic and real images show that the proposed method can generate a high-quality disparity map. Autors: Jae Young Lee;Rae-Hong Park; Appeared in: IEEE Journal of Selected Topics in Signal Processing Publication date: Oct 2017, volume: 11, issue:7, pages: 955 - 964 Publisher: IEEE
» Depth Estimation Using an Infrared Dot Projector and an Infrared Color Stereo Camera
 Abstract:This paper proposes a method of estimating depth from two kinds of stereo images: color stereo images and infrared stereo images. An infrared dot pattern is projected on a scene by a projector so that infrared cameras can capture the scene textured by the dots and the depth can be estimated even where the surface is not textured. The cost volumes are calculated for the infrared and color stereo images for each frame and are extended in the time direction to define a spatiotemporal cost volume (st-cost volume). We also extend the cost volume filter in the time direction by modifying the cross-based local multipoint filter (CLMF) and applying it to the st-cost volumes in order to restrain flicker on the time-varying depth maps. To get a reliable cost volume, the infrared and color st-cost volumes are integrated into a single cost volume by selecting the cost of either the infrared or the color st-cost volumes according to the size of the adaptive kernel used for the CLMF. Then, a graphcut is executed on the cost volume in order to estimate the disparity robustly even when the baselines of the stereo cameras are set wide enough to ensure spatially high resolution in the depth direction and the shapes of blocks are deformed by the affine transformation. A 2D graphcut is executed on each scan line to reduce the processing time and memory consumption. We experimented with the proposed method using infrared color stereo data sets of scenes in the real world and evaluated its effectiveness by comparing it with other recent stereo matching methods and depth cameras. Autors: Kensuke Hisatomi;Masanori Kano;Kensuke Ikeya;Miwa Katayama;Tomoyuki Mishina;Yuichi Iwadate;Kiyoharu Aizawa; Appeared in: IEEE Transactions on Circuits and Systems for Video Technology Publication date: Oct 2017, volume: 27, issue:10, pages: 2086 - 2097 Publisher: IEEE
» Deriving Bisimulation Relations from Path Extension Based Equivalence Checkers
 Abstract:Constructing bisimulation relations between programs as a means of translation validation has been an active field of study. The problem is in general undecidable. Currently available mechanisms suffer from drawbacks such as non-termination and significant restrictions on the structures of programs to be checked. We have developed a path extension based equivalence checking method as an alternative translation validation technique to alleviate these drawbacks. In this work, path extension based equivalence checking of programs (flowcharts) is leveraged to establish a bisimulation relation between a program and its translated version by constructing the relation from the outputs of the equivalence checker. Autors: Kunal Banerjee;Dipankar Sarkar;Chittaranjan Mandal; Appeared in: IEEE Transactions on Software Engineering Publication date: Oct 2017, volume: 43, issue:10, pages: 946 - 953 Publisher: IEEE
» Design and Analysis of a 1.8-GHz Open-Loop Modulator for Phase Modulation and Frequency Synthesis Using TDC-Based Calibration
 Abstract:A nonlinearity calibration technique is proposed for an open-loop phase modulator (PM), for wideband phase modulation, and for multiple-output, low-jitter clock generation. The design considerations and key performance aspects of the calibration technique are discussed. The PM integrates a digital phase-locked loop, local oscillator distribution network, and digital calibration. A prototype was implemented in 0.13- CMOS 1.8-GHz Gaussian frequency shift keying (GFSK) transmitter integrated circuit. Measurements on the prototype show that out-of-band quantization noise is 56 dB lower than that of the signal when transmitting 20-Mb/s GFSK signal and the rms error is only 3.2%. The power consumption of the PM is 18 mW. The measured spurious tones of the clock generation unit are below −46 dBc. Autors: Nitin Nidhi;Sudhakar Pamarti; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3975 - 3988 Publisher: IEEE
» Design and Analysis of a Bistable Vibration Energy Harvester Using Diamagnetic Levitation Mechanism
 Abstract:In this paper, a novel bistable vibration energy harvester using the diamagnetic levitation mechanism is conceptualized, designed, fabricated, and experimented comprehensively. The bistable energy harvester consists of a floating magnet, lifting magnets, diamagnetic plates, and coils. The lifting magnets placed symmetrically on the both sides of the base are designed to balance the weight of the floating magnet and produce a bistable potential well. The floating magnet is stabilized in the horizontal direction by diamagnetic plates which are made of pyrolytic graphite. Ring-shaped coils are designed for transduction and flanked by the side of diamagnetic plates. Theoretical modeling and analyses are carried out to compare with experimental data. Throughout the theoretical and experimental results, a peak power of is generated from a vibration level of 0.6 m/ over a range of 0.5–4.5 Hz. It is indicated that the bistable energy harvester can efficiently operate at extremely low frequencies (<5 Hz). Autors: Qiu-Hua Gao;Wen-Ming Zhang;Hong-Xiang Zou;Wen-Bo Li;Zhi-Ke Peng;Guang Meng; Appeared in: IEEE Transactions on Magnetics Publication date: Oct 2017, volume: 53, issue:10, pages: 1 - 9 Publisher: IEEE
» Design and Analysis of a Higher Order Power Filter for Grid-Connected Renewable Energy Systems
 Abstract:Harmonic compensation is regularly implemented for a grid-tied inverter to reduce the influence of the grid current and voltage harmonics. In this study, the L(LCL) filter, which is a high-order power filter for single-phase grid-tied voltage-source inverters, is designed and analyzed. In order to attenuate the high-frequency harmonics, additional resonant branch at the double of the switching frequency is added to the LLCL filter. The total inductance of this filter is almost less than the LLCL filter with the amount of the grid-side inductor. A comparative study on filter parameter design, size estimation, efficiency, stability, and dc-link dynamics in bidirectional power flow applications between the LLCL filter and the proposed L(LCL) filter has been conducted. The assessment of these studies is presented through both experimental hardware implementation and MATLAB/Simulink-based simulation on a 700 W, 120 V/60 Hz single-phase grid-tied inverter. It is concluded that, compared with the LLCL filter, the L(LCL) filter not only has less voltage drop and total component size, but also has better performance on reducing high-order current harmonics. Additionally, the L(LCL) filter has a smaller size, less losses, stable closed-loop control system, and compared with traditional LLCL filter, it does not add any control difficulty to the system. Autors: Arash Anzalchi;Masood Moghaddami;Amir Moghadasi;Maneli Malek Pour;Arif I. Sarwat; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4149 - 4161 Publisher: IEEE
» Design and Analysis of a Hybrid Radio Frequency and Visible Light Communication System
 Abstract:In this paper, a hybrid radio frequency (RF) and visible light communication (VLC) system is considered. A hybrid system with multiple VLC access points (APs) and RF APs is designed and analyzed. In indoor environments, VLC APs provide very high data rates whilst proving illumination, and RF APs offer ubiquitous coverage with moderate data rates. Since VLC networks piggyback on existing lighting infrastructures, they may not always be able to provide full coverage despite supporting very high data rates in some areas. Hence in practical deployments, the standalone VLC networks should be augmented in order to improve the per user data rate coverage. In this context, RF APs can be used to improve the per user rate coverage of VLC networks as well as to provide the ubiquitous control functionalities. In this paper, a simple RF deployment is proposed in order to improve the per user outage data rate performance of standalone VLC networks. It is assumed that the VLC system resources are fixed, and this paper quantifies the minimum spectrum and power requirements for a RF system, which after introduction to the VLC system, the hybrid RF/VLC system achieves certain per user rate coverage performances. Autors: Dushyantha A. Basnayaka;Harald Haas; Appeared in: IEEE Transactions on Communications Publication date: Oct 2017, volume: 65, issue:10, pages: 4334 - 4347 Publisher: IEEE
» Design and Analysis of a Wideband Gilbert Cell VGA in 0.25- $\mu {\rm m}$ InP DHBT Technology With DC-40-GHz Frequency Response
 Abstract:A differential variable gain amplifier (VGA) for wideband baseband signals has been designed, analyzed, and implemented in a 0.25- InP double heterojunction bipolar transistor technology with of 370/650 GHz. The 3-dB frequency bandwidth is measured to be 40 GHz with a maximum gain of 31 dB, resulting in a gain bandwidth product (GBP) of 1.4 THz, four times higher than previously reported GBP from a Gilbert cell-based VGAs. Furthermore, it measures a gain control range of 44 dB, a noise figure of 6.2 dB, an output third-order intercept point of 17 dBm, and a total power consumption of 350 mW from a single −7-V supply. With pseudorandom binary sequence test pattern signals, a clear open eye at 44 Gb/s was observed. The complete circuit, including on-chip integrated bias network and pads, measures 0.77 . We analyze the VGA for the 3-dB bandwidth and GBP by the use of zero-value time constants method to analytically identify the maximum GBP with respect to the design parameters and current bias. Autors: Marcus Gavell;Sten E. Gunnarsson;Iltcho Angelov;Zhongxia Simon He;Mattias Ferndahl;Herbert Zirath; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3962 - 3974 Publisher: IEEE
» Design and Analysis of Initial Access in Millimeter Wave Cellular Networks
 Abstract:Initial access is the process which allows a mobile user to first connect to a cellular network. It consists of two main steps: cell search (CS) on the downlink and random access (RA) on the uplink. Millimeter wave (mm-wave) cellular systems typically must rely on directional beamforming (BF) in order to create a viable connection. The BF direction must, therefore, be learned—as well as used—in the initial access process for mm-wave cellular networks. This paper considers four simple but representative initial access protocols that use various combinations of directional BF and omnidirectional transmission and reception at the mobile and the BS, during the CS and RA phases. We provide a system-level analysis of the success probability for CS and RA for each one, as well as of the initial access delay and user-perceived downlink throughput (UPT). For a baseline exhaustive search protocol, we find the optimal BS beamwidth and observe that in terms of initial access delay it is decreasing as blockage becomes more severe, but is relatively constant (about ) for UPT. Of the considered protocols, the best tradeoff between initial access delay and UPT is achieved under a fast CS protocol. Autors: Yingzhe Li;Jeffrey G. Andrews;François Baccelli;Thomas D. Novlan;Charlie Jianzhong Zhang; Appeared in: IEEE Transactions on Wireless Communications Publication date: Oct 2017, volume: 16, issue:10, pages: 6409 - 6425 Publisher: IEEE
» Design and Assessment of a 2.5-Gb/s Optical Wireless Transmission System for High Energy Physics
 Abstract:We designed, realized, and tested a 2.5-Gb/s optical wireless communication (OWC) system prototype, that should be employed in high energy physics (HEP) experiments, such as the compact muon solenoid (CMS). The system consists of off-the-shelf components, mainly a vertical cavity surface emitting laser (VCSEL) and a PIN photodiode with a proper ball lens. Since it should be used to transmit data among particle sensors in neighboring rings of the CMS, its target distance is 10 cm. Its most attractive feature is that it does not require a (complex) active tracking system because its measured tolerance to misalignment is around 1 mm (at bit error rate). We also report the X-rays irradiation tests of all components (Quartz lens, VCSEL, and PIN photodiode): None of them showed any degradation up till 238-Mrad (Si) dose. These results indicate that the designed OWC can be a viable solution for future HEP experiments. Autors: W. Ali;G. Cossu;A. Sturniolo;R. Dell’Orso;A. Messineo;F. Palla;E. Ciaramella; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 8 Publisher: IEEE
» Design and Characterization of an Exoskeleton for Perturbing the Knee During Gait
 Abstract:Objective: An improved understanding of mechanical impedance modulation in human joints would provide insights about the neuromechanics underlying functional movements. Experimental estimation of impedance requires specialized tools with highly reproducible perturbation dynamics and reliable measurement capabilities. This paper presents the design and mechanical characterization of the ETH Knee Perturbator: an actuated exoskeleton for perturbing the knee during gait. Methods: A novel wearable perturbation device was developed based on specific experimental objectives. Bench-top tests validated the device's torque limiting capability and characterized the time delays of the on-board clutch. Further tests demonstrated the device's ability to perform system identification on passive loads with static initial conditions. Finally, the ability of the device to consistently perturb human gait was evaluated through a pilot study on three unimpaired subjects. Results: The ETH Knee Perturbator is capable of identifying mass-spring systems within 15% accuracy, accounting for over 95% of the variance in the observed torque in 10 out of 16 cases. Five-degree extension and flexion perturbations were executed on human subjects with an onset timing precision of 2.52% of swing phase duration and a rise time of 36.5 ms. Conclusion: The ETH Knee Perturbator can deliver safe, precisely timed, and controlled perturbations, which is a prerequisite for the estimation of knee joint impedance during gait. Significance: Tools such as this can enhance models of neuromuscular control, which may improve rehabilitative outcomes following impairments affecting gait and advance the design and control of assistive devices. Autors: Michael R. Tucker;Camila Shirota;Olivier Lambercy;James S. Sulzer;Roger Gassert; Appeared in: IEEE Transactions on Biomedical Engineering Publication date: Oct 2017, volume: 64, issue:10, pages: 2331 - 2343 Publisher: IEEE
» Design and Characterization of High $di/dt$ CS-MCT for Pulse Power Applications
 Abstract:A high di/dt MOS-controlled thyristor with cathode-short structure (CS-MCT) is developed for pulse power applications. Compared with conventional MCT (con-MCT), the cathode short in the proposed CS-MCT greatly improves the dV/dt robustness. To achieve simultaneously high di/dt capability, special design of device characteristics parameter and consideration of 2-D transient carrier transport are carried out for the first time. Experimental results show that the proposed CS-MCT exhibits di/dt over 357 kA/cm/ and peak current of 27.1 kA/cm. Meanwhile, the improved practical dV/dt characteristics are validated in comparison with con-MCT at the same condition. The high di/dt property and simultaneously high dV/dt robustness indicate the proposed CS-MCT is a promising semiconductor pulse switch for pulse power applications. Autors: Wanjun Chen;Chao Liu;Yijun Shi;Yawei Liu;Hong Tao;Chengfang Liu;Qi Zhou;Zhaoji Li;Bo Zhang; Appeared in: IEEE Transactions on Electron Devices Publication date: Oct 2017, volume: 64, issue:10, pages: 4206 - 4212 Publisher: IEEE
» Design and Control of a High-Power Low-Loss DC–DC Converter for Mining Applications
 Abstract:This paper proposes a new design procedure for a bidirectional dc/dc LCL converter for potential megawatt range applications, including mobile mining equipment. This type of dc/dc converters employ two dc/ac converters and a passive LCL filter instead of a traditional high-frequency transformer. The exclusion of the transformer eliminates the core losses, while the switching losses are minimized by using soft switching operation. The proposed design method is different from previous publications as it ensures zero reactive power circulation, minimizes the size of the biggest capacitor, ensures stable and robust operation, and offers a good tradeoff between the capacitor size and the fault current in the converter under a dc fault condition. In addition to the proposed design, a simple and effective control strategy is proposed, which is based on single phase theory. The converter design and control have been evaluated by a digital simulation in EMTP-RV software environment for a 100 MW 300 kV/20 kV converter. Experimental validation has been carried out on a laboratory 200W 100V/20V prototype converter. Autors: Mohsen Ghaffarpour Jahromi;Galina Mirzaeva;Steven D. Mitchell; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 5105 - 5114 Publisher: IEEE
» Design and Decoupled Compensation Methods of a PM Motor Capable of 6-D Force/Torque Actuation for Minimum Bearing Reaction
 Abstract:This paper presents a methodology to design and control a permanent magnet (PM) motor capable of 6-D force/torque actuation for real-time compensation of external loads to achieve minimum bearing reaction (MBR). Unlike conventional multiphase designs, the current inputs to the stator-electromagnets (EMs) can be flexibly configured to enable 6-D force and/or torque actuation in one motor; two common motor structures (radial and axial types) are illustrated. Both the forward and inverse force/torque models are presented in terms of coordinate-independent kernel functions that characterize the force between an EM and a PM pole pair. Two closed-form solutions to the inverse model that solves for the current-input vector minimizing the total input energy to generate a desired force/torque vector, which can be computed within 1 ms, are derived and verified numerically. A feedforward MBR compensator designed to argument the proportional-integral-derivative (PID) speed regulator has been experimentally evaluated on a structurally smart spindle system to minimize bearing reactions. Experiments show that the MBR compensation effectively reduces vibrations and improves cutting quality. Autors: Kun Bai;Kok-Meng Lee;Jun Cao;Ruoyu Xu;Lei Li; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 2252 - 2264 Publisher: IEEE
» Design and Deployment of a Wireless Sensor Network for the Mar Menor Coastal Observation System
 Abstract:The Coastal Ocean Observation System of Murcia Region (OOCMUR) was established in 2008 as a major scientific and technological infrastructure in Spain with the main objective of studying the impact of global climate change in the Mediterranean. The coastal lagoon of Mar Menor in southeast Spain was chosen as the first region to be monitored because it is one of the most hypersaline coastal lagoons in the Mediterranean, with a limited exchange of water with the open sea, and it is the largest in Europe. Wireless sensor networks (WSNs) offer an efficient and innovative solution for oceanographic monitoring, allowing a higher density sensor deployment, at a lower cost. This paper presents the design of an ad hoc WSN system and a control software for Mar Menor monitoring using a buoy structure with sensors, energy harvesting, and communications platform. The study focuses on the oceanographic interest of the selected marine area, details of network deployment, the custom-designed sensor nodes, and the results of system operation. Autors: Cristina Albaladejo Pérez;Fulgencio Soto Valles;Roque Torres Sánchez;Manuel Jiménez Buendía;Francisco López-Castejón;Javier Gilabert Cervera; Appeared in: IEEE Journal of Oceanic Engineering Publication date: Oct 2017, volume: 42, issue:4, pages: 966 - 976 Publisher: IEEE
» Design and Deployment of Special Protection System for Kinmen Power System in Taiwan
 Abstract:If an extreme contingency strikes the Kinmen Island power system in Taiwan, it is very likely to cause blackouts. Although an underfrequency protection scheme has been applied, some drawbacks of the protection scheme hinder the Kinmen power system from avoiding blackouts. In the past decade, several blackouts have occurred in the Kinmen power system. To avoid further possible blackouts, a special protection system (SPS) is summoned. This paper describes the design guidelines and deployment procedures of an SPS for the Kinmen power system. The design depends on the Kinmen power system characteristics, and the deployment hinges upon the supervisory control and data acquisition system. Exquisite software was also developed to testify the Kinmen system SPS. Operational records have demonstrated that the proposed SPS can indeed prevent blackouts from occurring in the Kinmen power system. The design, implementation, and operation of the SPS dealt with in this paper might foster further deployments of other SPSs. Autors: Jin-Shyr Yang;Ching-Jung Liao;Yung-Fu Wang;Chia-Chi Chu;Sheng-Huei Lee;Yu-Jen Lin; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4176 - 4185 Publisher: IEEE
» Design and Evaluation of a Haptic Interface With Octopod Kinematics
 Abstract:The study of human motor control using functional magnetic resonance imaging gives rise to many challenges. One of them is the design of haptic interfaces that are compatible with the magnetic field. To achieve this, the existing haptic interfaces employ parallel kinematics. However, they are limited to three degrees of freedom (DOFs). When trying to offer more DOF without floating actuators, parallel kinematics suffer from direct kinematic singularities, and thus, strong mechanical anisotropy. In this paper, we determine an optimal six DOF kinematics that overcomes these limitations. To this end, we use performance indices such as singularity occurrence, worst case output capabilities, sensitivity, and the global isotropy index. The resulting Octopod kinematics avoids a range of direct kinematic singularities by design. Finally, we pre-sent and evaluate a non-magnetic-resonance-compatible prototype of this novel type of kinematics. Autors: Markus Kühne;Johannes Potzy;Roberto García-Rochín;Patrick van der Smagt;Angelika Peer; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 2091 - 2101 Publisher: IEEE
» Design and Implementation of Disturbance Compensation-Based Enhanced Robust Finite Control Set Predictive Torque Control for Induction Motor Systems
 Abstract:Finite-control-set-based predictive torque control (PTC) method has received more and more attention in recent years due to its fast torque response. However, it also has two drawbacks that could be improved. First, the torque reference in the cost function of the existing PTC method is generated by the proportional–integral speed controller, so torque reference's generation rate is not fast and its accuracy is low especially when the load torque is given suddenly and inertia value is varying. In addition, the variable prediction of the traditional PTC method depends on the system model, which also has the problem of parameter uncertainties. This paper investigates a disturbance observer (DOB)-based PTC approach for induction motor systems subject to load torque disturbances, parameter uncertainties, and time delays. Not only does the speed loop adopt a DOB-based feed-forward compensation method for improving the system disturbance rejection ability and robustness, but the flux, current, and torque predictions are also improved by using this technique. The simulation and experimental results verified the effectiveness of the proposed method. Autors: Junxiao Wang;Fengxiang Wang;Zhenbin Zhang;Shihua Li;José Rodríguez; Appeared in: IEEE Transactions on Industrial Informatics Publication date: Oct 2017, volume: 13, issue:5, pages: 2645 - 2656 Publisher: IEEE
» Design and Manufacture of Cosecant-Squared Complementary Reflectarrays for Low-Cost Applications
 Abstract:A novel solution for the manufacturing of a reflectarray antenna with cosecant-squared radiation pattern is presented. The unit cell simply consists of a 3-D printed nylon grid inserted in between two thick metallic plates. To introduce the required phase delay, C and reverse C slots are laser cut into the plate illuminated by the feeder. This solution allows obtaining an efficient, robust, and compact antenna with low-cost manufacturing process, even for no mass production. Measurements confirm the feasibility of the proposed solution and show its performances. Autors: Giorgio Carluccio;Agnese Mazzinghi;Angelo Freni; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 5220 - 5227 Publisher: IEEE
» Design and Performance Investigation of Novel Linear Switched Flux PM Machines
 Abstract:A novel partitioned primary linear switched flux permanent magnet (PLSFPM) machine is presented, which adopts an odd number of primary poles. For the design objective of minimum thrust ripple, the optimized novel PLSFPM machine with 9 primary/10 secondary (9/10) pole combination is obtained. To this optimized PLSFPM machine, the electromagnetic performance is analyzed in detail and compared with that of the original one. The merits of this 9/10 pole combination are also proved by comparative study with other three available pole combinations. Moreover, comparison between the proposed PLSFPM machine and a conventional linear switched flux permanent magnet machine has been performed, which shows that the proposed machine can achieve better performances under both open-circuit and load conditions. The corresponding prototype is manufactured and the influences of possible machining errors during manufacture on thrust force performance are discussed. Finally, the experiment is carried out, which verifies the predicted results. The research shows that the proposed PLSFPM machine with 9/10 pole combination has high thrust force and low thrust ripple. Autors: Qinfen Lu;Yihua Yao;Jiameng Shi;Yiming Shen;Xiaoyan Huang;Youtong Fang; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4590 - 4602 Publisher: IEEE
» Design and Prototyping a Smart Deep Brain Stimulator: An Autonomous Neuro-Sensing and Stimulating Electrode System
 Abstract:This article presents the design and prototyping of an innovative smart deep brain stimulator (SDBS) that consists of brain-implantable smart electrodes and a wireless-connected external controller. SDBS electrodes operate as completely autonomous electronic implants that are capable of sensing and recording neural activities in real time, performing local processing, and generating arbitrary waveforms for neuro-stimulation. A bidirectional, secure, fully passive wireless communication backbone was designed and integrated into this smart electrode to maintain contact between the electrodes and the controller. The standard EPC-Global protocol has been modified and adopted as the communication protocol in this design. The proposed SDBS was demonstrated and tested through a hardware prototypes. Autors: Muhammad S. Khan;Hai Deng; Appeared in: IEEE Intelligent Systems Publication date: Oct 2017, volume: 32, issue:5, pages: 14 - 27 Publisher: IEEE
» Design Approach to a Novel Dual-Mode Wideband Circular Sector Patch Antenna
 Abstract:A design approach to a novel wideband circular sector patch antenna is proposed. Design guidelines are laid down based on an approximate 1.5-wavelength, multimode magnetic dipole, and the cavity model. Then, the flared angle of the circular sector patch and the corresponding usable resonant modes for wideband radiation are determined. It is demonstrated that the resonant TM4/3,1 and the TM8/3,1 modes within a 270° circular sector patch radiator can be simultaneously excited, perturbed, and employed to form a wideband unidirectional radiation characteristic with two resonances. Prototype antennas are designed and fabricated to experimentally validate the dual-resonant wideband property on a single-layered substrate. It is further demonstrated that the antenna designed on a 5-mm-thick air substrate exhibits an available radiation bandwidth (ARB) of 14.5%, while the printed one designed on a 2-mm-thick modified Teflon substrate exhibits an ARB of 6.5%. It is evidently validated that the proposed approach can be employed to effectively enhance the operational bandwidth of microstrip patch antennas without increasing antenna profile, inquiring multiple radiators or employing reactance compensation techniques. Autors: Wen-Jun Lu;Qing Li;Sheng-Guang Wang;Lei Zhu; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 4980 - 4990 Publisher: IEEE
» Design for Manufacturability of an Off-Shore Direct-Drive Wind Generator: An Insight Into Additional Loss Prediction and Mitigation
 Abstract:Direct-drive generators to be used in off-shore wind farms are very large low-speed electric machines, which pose remarkable design and manufacturing challenges. Demand forecasts for this kind of machines are urging manufacturers to work out design and technological solutions capable of facilitating series production at competitive costs. This paper presents the development of an interior permanent-magnet generator design and technology aimed at reducing series manufacturing costs while preserving good performance levels. The focus is on two of the most critical issues in the machine design and analysis, namely, the prediction and reduction of eddy-current losses in stator conductors and in permanent magnets. The proposed design solutions are validated through the construction and testing of a 780 kVA generator prototype conceived for easy scalability to higher power ratings (up to around 2.5 MVA) by core length increase. Autors: Alberto Tessarolo;Fabio Luise;Stefano Pieri;Andrea Benedetti;Mauro Bortolozzi;Matteo De Martin; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4831 - 4842 Publisher: IEEE
» Design Method for Multiband WPDs Using Multisection $LC$ -Ladder Circuits
 Abstract:This letter describes a design method for multiband Wilkinson power dividers (WPDs) utilizing multisection -ladder circuits. The design method is inspired by even-and odd-mode analysis techniques and an -section matching network. Two trial dividers, which operate with dual-band/triband, were fabricated at a 300-MHz band. The measured relative bandwidths of these dividers were more than 45% and 60%, and their insertion losses were less than 1 dB. The sizes of these WPDs were mm2 and mm2, respectively. The measurement results for the fabricated dividers were in good agreement with theoretical results and the dividers show multiband characteristics. Autors: Yosuke Okada;Tadashi Kawai;Akira Enokihara; Appeared in: IEEE Microwave and Wireless Components Letters Publication date: Oct 2017, volume: 27, issue:10, pages: 894 - 896 Publisher: IEEE
» Design of 3-dB Hybrid Coupler Based on RGW Technology
 Abstract:Hybrid couplers are essential devices in various microwave circuits and systems, such as radar systems and beam forming networks. The development of this device is necessary along with the development of the new communication standards for the most modern guiding structures. One of the most recent and promising guiding technologies is the ridge gap waveguides, which is expected to play an essential role in the millimeter wave and submillimeter wave applications, not only the 5G communications but also other future communication. Therefore, standards are recommended to make use of the high-frequency guiding structures. In this paper, a design procedure for the hybrid couplers is presented. The frequency band of interest is centered at the 15 GHz, which can be deployed for both the 5G mobile communication and the airborne radar applications. The proposed design is fabricated and measured. The measured and simulated results are in excellent agreement. Autors: Shoukry I. Shams;Ahmed A. Kishk; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3849 - 3855 Publisher: IEEE
» Design of a 6-MW Solid-State Pulse Modulator Using Marx Generator for the Medical Linac
 Abstract:The linear accelerators (linacs) producing high energy and high power of electron-beam or X-ray beam have been used in medicine, industry, national security, etc. In the linac, the electrons are generated by the electron gun and accelerated in the accelerating column with the high-power RF fields. The high-voltage pulses from the pulse modulator are supplied to the RF power source and the electron gun. The pulse modulator is one of the big and expensive components in the linac. The commercial medical linacs commonly use the pulse modulator based on the thyratron-switched pulse-forming network. In order to improve the power efficiency, achieve the system compactness, and optimize the cost and space, the solid-state pulse modulator based on the Marx generator was proposed. The low-power solid-state pulse modulator was developed for the electron gun operation. The conceptual design and functional results were confirmed. In order to apply it to the RF power source, such as a magnetron or a klystron, the 6-MW pulse modulator with the same Marx scheme is proposed. It consists of 40 storage-switch stages and one high-voltage pulse transformer, producing the pulse of 50 kV and 120 A required by the magnetron in the medical linac. A storage-switch stage was designed for insulated gate bipolar transistors to switch high current of 280 A and 720 V and to use the capacitor of which was chosen for the voltage droop of 10% with the pulsewidth of . The prototype system with eight storage-switch stages was fabricated and tested with a load system. The performance results show that it can be extended to be the 6-MW solid-state pulse modulator. In this paper, we describe the design features, and discuss the results and also the future plan to optimize the solid-state pulse modulator - n the medical linac. Autors: Heuijin Lim;Dong Hyeok Jeong;Manwoo Lee;Sung Chae Ro; Appeared in: IEEE Transactions on Plasma Science Publication date: Oct 2017, volume: 45, issue:10, pages: 2734 - 2738 Publisher: IEEE
» Design of a Compact Pneumatic Power Generator With a Self-Regulating Mechanism for Mobile Application
 Abstract:The pneumatic actuator has high potential as an actuator for mobile devices due to its high power density, simplicity, compactness, light weight, and low cost. Moreover, inherent compliance of the pneumatic actuator improves safety and dynamic performance, which are strongly required for wearable robots. However, due to its need for a bulky air compressor, which is intended for stationary use, it is hard to apply a pneumatic actuator to mobile robots. To replace the air compressor, pneumatic energy sources utilizing chemical fuel were previously proposed and the potential of the hydrogen peroxide as a pneumatic energy source was proved. Nevertheless, pneumatic energy sources driven by hydrogen peroxide are generally bulky, which are hard to apply for a mesoscale system such as prosthetics. To address this challenge, this paper proposes novel pneumatic power generator driven by hydrogen peroxide. By applying a passive injection component and a mechanical pressure feedback mechanism, the pneumatic power generator regulates pressure by itself, without any control efforts, which results in compact size. In addition, a separated catalytic reactor and a fuel tank guarantee safety and mobility. The performances and energetic characteristics of the proposed pneumatic power generator are examined by both experiment and mathematical modeling. Autors: Kyung-Rok Kim;Yun-Pyo Hong;Kyung-Soo Kim;Soohyun Kim; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 1983 - 1991 Publisher: IEEE
» Design of a High-Speed Ferrite-Based Brushless DC Machine for Electric Vehicles
 Abstract:In this paper an analytical procedure for the preliminary design of a high-speed ferrite-based brushless dc machine (HS-BLDC) has been proposed. In particular, mechanical and electromagnetic modeling have been developed in order to take into account their mutual influence in the definition of the geometry of the electrical machine. In addition, suitable design targets have been imposed in accordance with electric vehicle application requirements. Hence, several mechanical and electromagnetic constraints have been introduced in order to comply with high-speed operation, preventing demagnetization issues of ferrite magnets as well. Subsequently, an HS-BLDC characterized by an inner rotor configuration has been designed in accordance with the proposed methodology. The analytical procedure and the corresponding results have been reported and validated by means of finite element analyses, highlighting the effectiveness of the proposed configuration and design solutions. Autors: Alfonso Damiano;Andrea Floris;Giuseppe Fois;Ignazio Marongiu;Mario Porru;Alessandro Serpi; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4279 - 4287 Publisher: IEEE
» Design of A Novel Highly EMI-Immune CMOS Miller OpAmp Considering Channel Length Modulation
 Abstract:This paper presents a novel CMOS Miller operational amplifier (OpAmp) that has high immunity to electromagnetic interference (EMI). The proposed CMOS Miller OpAmp uses the replica concept with the source-buffered technique in order to achieve high EMI immunity across a wide range of frequencies (10 MHz to 1 GHz). The proposed amplifier is designed using the first-order quadratic mathematical model. The modeling includes the body effect and channel length modulation. The circuit has been fabricated using 0.18 mixed-mode CMOS technology. Measurement results illustrate how the proposed Miller OpAmp reduces susceptibility to EMI even in the presence of high-amplitude interferences that are as high as 1 Vpp. Experimental results show that the maximum EMI-induced output offset voltage for the proposed Miller OpAmp is less than 10 mV over a wide range of frequencies (10 MHz to 1 GHz) when a 900 mVpp EMI signal is injected into the noninverting input. In contrast, the classic Miller OpAmp generates a maximum output offset voltage of 215 mV at 1 GHz under the same operating conditions. The measured results of the EMI-induced input offset corroborates the circuit simulations. Autors: Subrahmanyam Boyapati;Jean-Michel Redouté;Maryam Shojaei Baghini; Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers Publication date: Oct 2017, volume: 64, issue:10, pages: 2679 - 2690 Publisher: IEEE
» Design of a Parallel Actuated Exoskeleton for Adaptive and Safe Robotic Shoulder Rehabilitation
 Abstract:Powered exoskeletons can facilitate after-stroke rehabilitation of patients with shoulder disabilities. Designs using serial mechanisms usually result in complicated and bulky exoskeletons. This paper presents a new parallel actuated shoulder exoskeleton that consists of two spherical mechanisms, two slider crank mechanisms, and a gravity balancing mechanism. The actuators are grounded and placed side-by-side. Thus, better inertia properties can be achieved while lightweight and compactness are maintained. An adaptive mechanism with only passive joints is introduced to compensate for the exoskeleton–limb misalignment and size variation among different subjects. Linear series elastic actuators (SEAs) are proposed to obtain accurate force and impedance control at the exoskeleton–limb interface. The total number of force sensors and actuators is minimized using the adaptive mechanism and SEAs. An exoskeleton prototype is shown to provide bidirectional actuation between the exoskeleton and upper limb, which is required for various rehabilitation processes. We expect this design can provide a means of shoulder rehabilitation. Autors: Hsiang-Chien Hsieh;Dian-Fu Chen;Li Chien;Chao-Chieh Lan; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 2034 - 2045 Publisher: IEEE
» Design of Contract-Based Trading Mechanism for a Small-Cell Caching System
 Abstract:Recently, content-aware-enabled distributed cach- ing relying on local small-cell base stations (SBSs), namely, small-cell caching, has been intensively studied for reducing transmission latency as well as alleviating the traffic load over backhaul channels. In this paper, we consider a commercialized small-cell caching system consisting of a network service provider (NSP), several content providers (CPs), and multiple mobile users (MUs). The NSP, as a network facility monopolist in charge of the SBSs, leases its resources to the CPs for gaining profits. At the same time, the CPs are intended to rent the SBSs for providing better downloading services to the MUs. We focus on solving the profit maximization problem for the NSP within the framework of contract theory. To be specific, we first formulate the utility functions of the NSP and the CPs by modeling the MUs and SBSs as two independent Poisson point processes. Then, we develop the optimal contract problem for an information asymmetric scenario, where the NSP only knows the distribution of CPs’ popularity among the MUs. Also, we derive the necessary and sufficient conditions of feasible contracts. Lastly, the optimal contract solutions are proposed with different CPs’ popularity parameter . Numerical results are provided to show the optimal quality and the optimal price designed for each CP. In addition, we find that the proposed contract-based mechanism is superior to the benchmarks from the perspective of maximizing the NSP’s profit. Autors: Tingting Liu;Jun Li;Feng Shu;Meixia Tao;Wen Chen;Zhu Han; Appeared in: IEEE Transactions on Wireless Communications Publication date: Oct 2017, volume: 16, issue:10, pages: 6602 - 6617 Publisher: IEEE
» Design of Dual Purpose No-Voltage Combined Windings for Bearingless Motors
 Abstract:A winding design approach is proposed to create a single motor winding, which is able to produce both radial force and torque. This approach can be used to design new bearingless motors, as well as to transform conventional motor designs into bearingless motors by simply modifying the winding end connections. The resulting winding has two sets of terminal connections, one for torque and one for suspension. The suspension terminals experience no motional-electromotive force when the rotor is centered, which means that the suspension drive can have a low voltage rating and that rotor vibrations can be passively dampened by simply short-circuiting the suspension terminals. Bearingless motors that use these so-called dual purpose no voltage windings can be designed to have higher torque density and lower losses associated with the magnetic suspension operation than traditional bearingless motors, which utilize separate torque and suspension windings. It will be shown that many popular winding designs, including fractional-slot and concentrated windings, can be realized as dual purpose no-voltage windings. The proposed approach applies to traditional pole-pair bearingless motors, as well as the bearingless consequent-pole and ac homopolar motors. Fractional-slot motor winding theory is used to derive the new winding requirements and a generalized design procedure; example designs are explored through finite element analysis and experimental results from a hardware prototype of a bearingless ac homopolar motor. Autors: Eric Loren Severson;Robert Nilssen;Tore Undeland;Ned Mohan; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4368 - 4379 Publisher: IEEE
» Design of Dynamic Wavelet Packet Division Multiplexing
 Abstract:At the reception of wireless communications the wavelet packet-division multiplexing (WPDM) has shown susceptibility to multipath fading. Inspired by WPDM, this paper proposes a new scheme of multiplexing, which has been called “Dynamic Wavelet Packet-Division Multiplexing (DWPDM)”, that allow adapt to the channel conditions and improve their performance both in time-variant as time-invariant channels. The proposed scheme also allow increase the quality of service and improve the security of transmission of binary message thanks to the random variation in the time of the carries or wavelet packet functions. The scheme were evaluated by simulation in three communication scenarios: AWGN channel, selective fading channel and slowly-varying notch channel, showing improvement compared with WPDM, Branch-Hopped WPDM and WOFDM. Autors: Juan Pablo Hoyos Sanchez;Pablo Emilio Jojoa Gomez; Appeared in: IEEE Latin America Transactions Publication date: Oct 2017, volume: 15, issue:10, pages: 1834 - 1839 Publisher: IEEE
» Design of License Plate RFID Tag Antenna Using Characteristic Mode Pattern Synthesis
 Abstract:A novel design of the passive license plate radio frequency identification tag antenna in UHF band based on the characteristic mode theory (CMT) is proposed in this paper. The license plate is operated as a tag antenna since it is conductor (made of aluminum). A desired up-tilted pattern beam is achieved successfully by using a direct CMT-based radiation pattern synthesis procedure. The pattern can be expanded as a superposition of some specific characteristic modes pattern, which is identified according to characteristic mode analysis of the plate. Four coupling slots are exploited to excite the selected modes current distribution. The mode weighting coefficients can be tuned to form the desired pattern beam by changing the relative phase between the coupling slots. The feed structure is carefully designed without damaging the layout of characters and numbers on the license plate. The synthesized radiation pattern corresponds with the pattern simulated by HFSS. The measured radiation pattern proves that the proposed design is reliable and applicable. The measured read range is about 20 m, which can satisfy the actual requirements. Autors: Zhipeng Liang;Jun Ouyang;Feng Yang;Longjian Zhou; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 4964 - 4970 Publisher: IEEE
» Design of Miniaturized Triplexers via Sharing a Single Triple-Mode Cavity Resonator
 Abstract:A novel approach for design of a miniaturized cavity triplexer is proposed in this paper by using triple-mode resonator (TMR) as a common feeder of three frequency channels in a triplexer. Three frequency channels are generated by three fundamental modes of a single rectangular triple-mode cavity resonator. Without installing any connection-oriented junction network, i.e., T-junction or star junction, only coupling slots are adopted herein to achieve required coupling coefficients and external quality factors toward the specified Chebyshev responses in the three passbands simultaneously. High isolation among these three separated bands can be effectively achieved owing to the modal orthogonality via sharing a common TMR structure as a feeder. Two triplexers are then designed and fabricated using varied topologies. The hybrid resonator triplexer method is presented as the first approach by using a TMR as a feeder to feed three sets of single-mode cavity bandpass filters. As the second approach, the triple-mode triplexer (TMT) method is developed by cascading a few TMRs to form a multistage higher order TMT. Finally, two fabricated triplexer prototypes are tested for experimental verification of the proposed design methodology. Good agreement between measurement and simulation is achieved. Autors: Jing-Yu Lin;Sai-Wai Wong;Lei Zhu;Qing-Xin Chu; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3877 - 3884 Publisher: IEEE
» Design Procedure of Flux Reversal Permanent Magnet Machines
 Abstract:Flux reversal permanent magnet machines (FRPMMs) exhibit many advantages such as simple rotor configuration, high torque density, fast transient response, etc. However, the general analytical design procedure of FRPMMs has not been established. Thus, this paper mainly focuses on developing an analytical design methodology of three-phase FRPMMs. First, the sizing equations are derived based on a magneto motive force-permeance model. Then, the influences of several key parameters in the sizing equation, including slot–pole combination, airgap radius, electric loading, and equivalent magnetic loading on the torque density, are analyzed. Moreover, the feasible slot–pole combinations are summarized and the corresponding winding type of each combination is recommended in order to maximize the output torque. Additionaly, the detailed geometric design of stator and rotor is presented. Finally, the proposed analytical design procedure is verified by finite element analysis and experiments on a 12-stator-slot/17-rotor-slot FRPMM prototype. Autors: Yuting Gao;Dawei Li;Ronghai Qu;Jian Li; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4232 - 4241 Publisher: IEEE
» Design, Fabrication, and Characterization of a High Q Silica Nanobeam Cavity With Orthogonal Resonant Modes
 Abstract:We design and fabricate a high silica nanobeam cavity that supports both transverse electric (TE) and transverse magnetic modes in the 1.55  m wavelength range. The values obtained for both modes exceed and are the highest reported values for photonic crystal (PhC) nanocavities made of silica. We also investigate the optimum conditions for coupling with the cavity in a side-coupled configuration. We achieve a coupling efficiency of 87% with the TE mode while maintaining a loaded of more than . We also found that the presence of a coupled waveguide reduces the intrinsic of the cavity, depending on the gap distance. This provides useful quantitative information for establishing an efficient scheme for coupling with low-index PhC nanocavities. Autors: Tomohiro Tetsumoto;Hajime Kumazaki;Kentaro Furusawa;Norihiko Sekine;Takasumi Tanabe; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 9 Publisher: IEEE
» Design, Fabrication, and Characterization of Scandium Aluminum Nitride-Based Piezoelectric Micromachined Ultrasonic Transducers
 Abstract:This paper presents the design, fabrication, and characterization of piezoelectric micromachined ultrasound transducers (PMUTs) based on scandium aluminum nitride (ScxAl1–xN) thin films (x = 15%). ScAlN thin film was prepared with a dual magnetron system and patterned by a reactive ion etching system utilizing chlorine-based chemistry with an etching rate of 160 nm/min. The film was characterized by X-ray diffraction, which indicated a crystalline structure expansion compared with pure AlN and a well-aligned ScAlN film. ScAlN PMUTs were fabricated by a two-mask process based on cavity SOI wafers. ScAlN PMUTs with 50- and 40- diameter had a large dynamic displacement sensitivity measured in air of 25 nm/V at 17 MHz and 10 nm/V at 25 MHz, twice that of AlN PMUTs with the same dimensions. The peak displacement as a function of electrode coverage was characterized, with maximum displacement achieved with an electrode radius equal to 70% of the PMUT radius. Electrical impedance measurements indicated that the ScAlN PMUTs had 36% greater electromechanical coupling coefficient ( compared with AlN PMUTs. The output pressure of a ScAlN PMUT array was 0.7 kPa/V at ~1.7 mm away from the array, which is approximately three times greater that of an AlN PMUT array with the same element geometry and fill factor measured at the same distance. Acoustic spreading loss and PMUT insertion loss from mechanical transmit to receive were characterized with a 15 15 ScAlN PMUT array via hydrophone and laser Doppler vibrometer. [17509-2017] Autors: Qi Wang;Yipeng Lu;Sergey Mishin;Yury Oshmyansky;David A. Horsley; Appeared in: Journal of Microelectromechanical Systems Publication date: Oct 2017, volume: 26, issue:5, pages: 1132 - 1139 Publisher: IEEE
» Design, Modeling, Lab, and Field Tests of a Mechanical-Motion-Rectifier-Based Energy Harvester Using a Ball-Screw Mechanism
 Abstract:In this paper, a new-type of mechanical-motion-rectifier-based energy harvesting shock absorber using a ball-screw mechanism and two one-way clutches is proposed to replace conventional oil dampers in vehicle suspensions. The proposed energy-harvesting shock absorber can work as a controllable shock absorber as well as an energy harvester. The challenge to harvest energy from reciprocating suspension vibration is solved by integrating a mechanical motion rectifier in the proposed design, which can convert reciprocating vibration into unidirectional rotation of a generator. As a result, the proposed shock absorber achieves high energy-harvesting efficiency by enabling the generator to rotate at a relatively steady speed during irregular vibrations and improves system reliability by reducing impact forces in transmission gears. In addition, the backlash of the proposed shock absorber is significantly reduced due to the use of the ball-screw mechanism, which further increases transmission durability and efficiency. Lab and field tests are carried out to experimentally characterize the proposed energy-harvesting shock absorber. The field testing results show that, when the modified vehicle is driven on a paved road at 40 mph, the proposed energy-harvesting shock absorber is able to reduce the root-mean-square value of chassis acceleration by 11.12% over the oil shock absorber and simultaneously harvest an average power of 13.3 W for a representative period of 8 s. Autors: Yilun Liu;Lin Xu;Lei Zuo; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 1933 - 1943 Publisher: IEEE
» Designing Three-Dimensional Cellular Automata Based Video Authentication With an Optical Integral Imaging Generated Memory-Distributed Watermark
 Abstract:Integral imaging for image watermarking is attracting a great deal of interest as it provides high processing speed and data redundancy property. Traditional video watermarking algorithms are mostly based on discrete transform domains, such as the discrete cosine transform and discrete wavelet transform. Most of these algorithms generally provide one transform plane for watermarking. In this paper, we propose a video watermarking by employing three-dimensional (3-D) cellular automata (CA) transform and perfect-reconstruction integral imaging (PRII). Compared to the existing works, the main strength of this paper is to utilize a 3-D CA transform to produce multiple transform planes for watermark embedding, so that greatly improve the security; decompose watermark into a series of elemental images using integral imaging to enhance the robustness; and employ perfect-reconstruction filter into the iterative back-projection process thus resolving the ringing artifacts problems. Experimental results show that the proposed PRII-based watermarking method outperforms other similar watermarking methods and is robust to a wide range of attacks, e.g., Gaussian noise, salt and pepper noise, frame clipping, JPEG compression, and median filter attack. Autors: Xiao-Wei Li;Seok-Tae Kim;Qiong-Hua Wang; Appeared in: IEEE Journal of Selected Topics in Signal Processing Publication date: Oct 2017, volume: 11, issue:7, pages: 1200 - 1212 Publisher: IEEE
» Designing, Manufacturing and Testing of a Piezoelectric Polymer Film In-Sole Sensor for Plantar Pressure Distribution Measurements
 Abstract:We have designed, manufactured, and tested a prototype of an in-sole plantar pressure sensor. The sensor is made of a piezoelectric polymer film (polyvinylidenefluoride, PVDF) with evaporated copper electrodes. The size and the location of measuring sites are carefully considered to produce a light-weighted, practical, and inexpensive matrix sensor for measurement of plantar pressure distribution. The sensor consists of eight measurement locations: hallux, first metatarsal head (under both sesamoid bones), metatarsal heads 2–5 and heel. The developed in-sole sensor was evaluated through piezoelectric sensitivity measurements and test measurements with subjects (used as a platform sensor). Average peak-to-peak pressures from 58 to 486 kPa were obtained in plantar pressure measurements. The in-sole sensor can be used to prevent pressure ulcers. Also other application areas for the sensor are available, e.g., rehabilitation and sports. The developed sensor enables unobtrusive and long-term plantar pressure measurements. In future, an option for manufacturing the PVDF in-soles may be printing of desired electrode pattern on PVDF material, that would allow fast production, and if needed, the production of even individual in-soles. Autors: Satu Rajala;Raisa Mattila;Ilkka Kaartinen;Jukka Lekkala; Appeared in: IEEE Sensors Journal Publication date: Oct 2017, volume: 17, issue:20, pages: 6798 - 6805 Publisher: IEEE
» Desirably Adjusting Gain Margin, Phase Margin, and Corresponding Crossover Frequencies Based on Frequency Data
 Abstract:This paper presents an analytical method to tune a fixed-structure fractional-order compensator for satisfying desired phase and gain margins with adjustable crossover frequencies. The proposed method is based on the measured frequency data of the plant. Since no analytical model for the plant is needed in the compensator tuning procedure, the resulted compensator does not depend on the order and complexity of the plant. Also, sufficient conditions for the existence of a compensator with no zero and pole in the right half-plane for satisfying the aforementioned objectives are analytically derived. Furthermore, different hardware-in-the-loop experimental results are presented to show the efficiency of the proposed tuning method. Autors: Negin Sayyaf;Mohammad Saleh Tavazoei; Appeared in: IEEE Transactions on Industrial Informatics Publication date: Oct 2017, volume: 13, issue:5, pages: 2311 - 2321 Publisher: IEEE
» Detailed Measurement Study of Spatial Similarity in Spectrum Use in Dense Urban Environments
 Abstract:We present a detailed analysis of spectrum use and radio environment dynamics based on extensive measurement campaigns in the two European metropolitan areas of Paris and London. Our focus is twofold. First, for the Paris case we focus on frequency bands assigned to cellular systems. In particular, we present extensive cross-correlational analyses describing the complex interdependencies in spectrum use between the various bands, together with their spatial correlation structures. Our results show that there are strong correlations in many instances, but these are not present in all regions and for all technologies. Second, we focus on characterizing the variability in spectrum use using novel methodology going beyond the classical spatial correlation analysis. For this, we carry out detailed measurements over different areas of London, using both moving measurement platforms as well as a stationary reference. The utilized measurement approach allows us to study the scales of variation in an area, which are important for secondary access systems and cognitive network types of deployments that have to understand and exploit those. Such deployments depend on various boundary conditions on the radio dynamics. Our major methodological contribution is that we do not only use a local average with the simplest spatial dependency measure (linear correlation), but we retain all the data and quantify spatial similarly using distribution-wide metrics. This approach also allows us to question how much information can indeed be shared from relay nodes or single nodes measurements that try to capture dynamics of larger operating regions. Autors: Alexandros Palaios;Janne Riihijärvi;Oliver Holland;Petri Mähönen; Appeared in: IEEE Transactions on Vehicular Technology Publication date: Oct 2017, volume: 66, issue:10, pages: 8951 - 8963 Publisher: IEEE
» Detecting Clinically Meaningful Shape Clusters in Medical Image Data: Metrics Analysis for Hierarchical Clustering Applied to Healthy and Pathological Aortic Arches
 Abstract:Objective: Today's growing medical image databases call for novel processing tools to structure the bulk of data and extract clinically relevant information. Unsupervised hierarchical clustering may reveal clusters within anatomical shape data of patient populations as required for modern precision medicine strategies. Few studies have applied hierarchical clustering techniques to three-dimensional patient shape data and results depend heavily on the chosen clustering distance metrics and linkage functions. In this study, we sought to assess clustering classification performance of various distance/linkage combinations and of different types of input data to obtain clinically meaningful shape clusters. Methods: We present a processing pipeline combining automatic segmentation, statistical shape modeling, and agglomerative hierarchical clustering to automatically subdivide a set of 60 aortic arch anatomical models into healthy controls, two groups affected by congenital heart disease, and their respective subgroups as defined by clinical diagnosis. Results were compared with traditional morphometrics and principal component analysis of shape features. Results: Our pipeline achieved automatic division of input shape data according to primary clinical diagnosis with high F-score (0.902 ± 0.042) and Matthews correlation coefficient (0.851 ± 0.064) using the correlation/weighted distance/linkage combination. Meaningful subgroups within the three patient groups were obtained and benchmark scores for automatic segmentation and classification performance are reported. Conclusion: Clustering results vary depending on the distance/linkage combination used to divide the data. Yet, clinically relevant shape clusters and subgroups could be found with high specificity and low miscl- ssification rates. Significance: Detecting disease-specific clusters within medical image data could improve image-based risk assessment, treatment planning, and medical device development in complex disease. Autors: Jan L. Bruse;Maria A. Zuluaga;Abbas Khushnood;Kristin McLeod;Hopewell N. Ntsinjana;Tain-Yen Hsia;Maxime Sermesant;Xavier Pennec;Andrew M. Taylor;Silvia Schievano; Appeared in: IEEE Transactions on Biomedical Engineering Publication date: Oct 2017, volume: 64, issue:10, pages: 2373 - 2383 Publisher: IEEE
» Detecting Malicious Activity With DNS Backscatter Over Time
 Abstract:Network-wide activity is when one computer (the originator) touches many others (the targets). Motives for activity may be benign (mailing lists, content-delivery networks, and research scanning), malicious (spammers and scanners for security vulnerabilities), or perhaps indeterminate (ad trackers). Knowledge of malicious activity may help anticipate attacks, and understanding benign activity may set a baseline or characterize growth. This paper identifies domain name system (DNS) backscatter as a new source of information about network-wide activity. Backscatter is the reverse DNS queries caused when targets or middleboxes automatically look up the domain name of the originator. Queries are visible to the authoritative DNS servers that handle reverse DNS. While the fraction of backscatter they see depends on the server’s location in the DNS hierarchy, we show that activity that touches many targets appear even in sampled observations. We use information about the queriers to classify originator activity using machine-learning. Our algorithm has reasonable accuracy and precision (70–80%) as shown by data from three different organizations operating DNS servers at the root or country level. Using this technique, we examine nine months of activity from one authority to identify trends in scanning, identifying bursts corresponding to Heartbleed, and broad and continuous scanning of secure shell. Autors: Kensuke Fukuda;John Heidemann;Abdul Qadeer; Appeared in: IEEE/ACM Transactions on Networking Publication date: Oct 2017, volume: 25, issue:5, pages: 3203 - 3218 Publisher: IEEE
» Detecting Sudden and Gradual Drifts in Business Processes from Execution Traces
» Detection of Cars in High-Resolution Aerial Images of Complex Urban Environments
 Abstract:Detection of small targets, more specifically cars, in aerial images of urban scenes, has various applications in several domains, such as surveillance, military, remote sensing, and others. This is a tremendously challenging problem, mainly because of the significant interclass similarity among objects in urban environments, e.g., cars and certain types of nontarget objects, such as buildings’ roofs and windows. These nontarget objects often possess very similar visual appearance to that of cars making it hard to separate the car and the noncar classes. Accordingly, most past works experienced low precision rates at high recall rates. In this paper, a novel framework is introduced that achieves a higher precision rate at a given recall than the state of the art. The proposed framework adopts a sliding-window approach and it consists of four stages, namely, window evaluation, extraction and encoding of features, classification, and postprocessing. This paper introduces a new way to derive descriptors that encode the local distributions of gradients, colors, and texture. Image descriptors characterize the aforementioned cues using adaptive cell distributions, wherein the distribution of cells within a detection window is a function of its dominant orientation, and hence, neither the rotation of the patch under examination nor the computation of descriptors at different orientations is required. The performance of the proposed framework has been evaluated on the challenging Vaihingen and Overhead Imagery Research data sets. Results demonstrate the superiority of the proposed framework to the state of the art. Autors: Mohamed ElMikaty;Tania Stathaki; Appeared in: IEEE Transactions on Geoscience and Remote Sensing Publication date: Oct 2017, volume: 55, issue:10, pages: 5913 - 5924 Publisher: IEEE
» Detection of False-Data Injection Attacks in Cyber-Physical DC Microgrids
 Abstract:Power electronics-intensive dc microgrids use increasingly complex software-based controllers and communication networks. They are evolving into cyber-physical systems (CPS) with sophisticated interactions between physical and computational processes, making them vulnerable to cyber attacks. This paper presents a framework to detect possible false-data injection attacks (FDIAs) in cyber-physical dc microgrids. The detection problem is formalized as identifying a change in sets of inferred candidate invariants. Invariants are microgrids properties that do not change over time. Both the physical plant and the software controller of CPS can be described as Simulink/Stateflow (SLSF) diagrams. The dynamic analysis infers the candidate invariants over the input/output variables of SLSF components. The reachability analysis generates the sets of reachable states (reach sets) for the CPS modeled as hybrid automata. The candidate invariants that contain the reach sets are called the actual invariants. The candidate invariants are then compared with the actual invariants, and any mismatch indicates the presence of FDIA. To evaluate the proposed methodology, the hybrid automaton of a dc microgrid, with a distributed cooperative control scheme, is presented. The reachability analysis is performed to obtain the reach sets and, hence, the actual invariants. Moreover, a prototype tool, HYbrid iNvariant GEneratoR, is extended to instrument SLSF models, obtain candidate invariants, and identify FDIA. Autors: Omar Ali Beg;Taylor T. Johnson;Ali Davoudi; Appeared in: IEEE Transactions on Industrial Informatics Publication date: Oct 2017, volume: 13, issue:5, pages: 2693 - 2703 Publisher: IEEE
» Detection of Underwater Targets Using a Subspace-Based Method With Learning
 Abstract:This paper introduces a new subspace-based detection method for multichannel (high frequency and broadband) synthetic aperture sonar (SAS) imagery. An image-dependent dictionary learning method is applied to form the appropriate dictionary matrices for representing target and nontarget image snippets. The hypothesis testing is done by forming a test statistic that relies on the residual error power ratio in representing an unknown image snippet using the target and nontarget dictionary matrices. To avoid the computational bottleneck in most dictionary learning methods, a new recursive method is introduced which does not require any matrix inversion or singular value decomposition (SVD). The proposed detection method was then implemented and benchmarked against a matched subspace detection method for detecting mine-like objects. Results are then presented on two sonar imagery data sets collected in two geographically disparate locations. Autors: Mahmood R. Azimi-Sadjadi;Nick Klausner;Justin Kopacz; Appeared in: IEEE Journal of Oceanic Engineering Publication date: Oct 2017, volume: 42, issue:4, pages: 869 - 879 Publisher: IEEE
» Determination of Original Nondegraded and Fully Degraded Magnetic Characteristics of Material Subjected to Laser Cutting
 Abstract:The degrading effect of laser cutting on steel sheet material, and thus on the material's magnetic characteristics, is much less understood than that of mechanical cutting. Furthermore, the degrading influence on the magnetic properties is still difficult to determine. This paper focuses on the modeling of the degrading influence of laser cutting on the magnetic properties of electrical steel sheets. As the degradation depth and the degradation profile are still difficult to define, a method is needed, which takes the effect of laser cutting into account, but without the need of knowing the degradation profile exactly. This paper shows that a method that does not require any information on the physical phenomena that are introduced by the cutting process and that has already been verified for mechanically cut samples can also be applied to laser-cut samples, although the deterioration mechanisms and the resulting degradation profile and depths differ. Magnetic characteristics are identified for two different material zones and subsequently inserted into a finite-element model, which accounts for arbitrary geometries. The simulation results for the influence of laser cutting on the magnetic characteristics of the stator lamination stacks are verified by measurements, including three different materials and frequencies. Autors: Madeleine Bali;Herbert De Gersem;Annette Muetze; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4242 - 4251 Publisher: IEEE
» Determine Q–V Characteristics of Grid-Connected Wind Farms for Voltage Control Using a Data-Driven Analytics Approach
 Abstract:Due to the varying and intermittent nature of wind resource, grid-connected wind farms pose significant technical challenges to power grid on power quality and voltage stability. Wind farm Q–V characteristic curve at the point of interconnection (POI) can offer valuable information for voltage control actions and provide essential indication about voltage stability. Data-driven analytics is a promising approach to determine characteristics of a large complex system, a physical model of which is difficult to obtain. In this paper, data-driven analytics is used to determine Q–V curve of grid-connected wind farms based on measurement data recorded at the POI. Different curve-fitting models, such as polynomial, Gaussian, and rational, are evaluated, and the best fit is determined based on different graphical and numerical evaluation metrics. A case study is conducted using field measurement data at two grid-connected wind farms currently in operation in Newfoundland and Labrador, Canada. It is found that the Gaussian (degree 2) model describes the Q–V relationship most accurately for the two wind farms. The obtained functions and processed data can be used in the voltage controller design. The plotted QV curve can also be used to determine the reactive margin at the POI for voltage stability evaluation. As a generic method, the proposed approach can be employed to determine Q–V characteristic curve of any grid-connected large wind farms. Autors: Chowdhury Andalib-Bin-Karim;Xiaodong Liang;Nahidul Khan;Huaguang Zhang; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4162 - 4175 Publisher: IEEE
» Deuterated SiN/SiON Waveguides on Si Platform and Their Application to C-Band WDM Filters
 Abstract:We describe low-loss SiN/SiON waveguides for wavelength-division-multiplexing filters on a Si platform. The key technology is a low-temperature deposition of refractive-index-controllable SiN/SiON films by using a hydrogen-free gas source (SiD4), which avoids the strong optical absorption due to N-H bond. Using this technology, we demonstrate a low-loss ring resonator with a SiN waveguide, whose loss is 0.47 dB/cm at 1550 nm. It shows excess loss of 2.7 dB, a 3-dB bandwidth of 0.13 nm, and an extinction ratio of 27 dB in the entire C band. In addition, we also demonstrate a polarization-insensitive arrayed-waveguide grating with a SiON waveguide, whose loss is 0.29 dB/cm at 1550 nm. It shows insertion loss of 5.3 dB, crosstalk of less than −27 dB, and polarization insensitivity in the entire C band. Autors: Tatsurou Hiraki;Takuma Aihara;Hidetaka Nishi;Tai Tsuchizawa; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 7 Publisher: IEEE
» Developing Millimeter-Wave Planar Antenna With a Cosecant Squared Pattern
 Abstract:This communication reports a novel planar array antenna having a cosecant squared pattern for millimeter-wave communication systems. The substrate integrated waveguide, which has high quality factor, low transmission loss, and no parasitic radiation, has been adopted to develop the proposed antenna. To improve the design efficiency, the aggressive space mapping (ASM) algorithm is used for synthesizing the desired excitations with low computation cost and high accuracy. A radiation model that considers mutual couplings among element antennas is developed based on the active element pattern for the coarse model of the ASM. And the genetic algorithm is adopted for the parameter mapping and extraction of the ASM process. As a demonstration, a prototype has been designed with a center frequency of 42.6 GHz, and experiments are carried out to verify the design. The measured results show that the measured antenna has a cosecant squared region up to 40°, a gain of 17.7 dBi at 42.6 GHz, and the maximum sidelobe is lower than −16.5 dB. The proposed antenna can be used for the base station of the long-range Qlink-Pan communication system. Autors: Zhang-Cheng Hao;Muxin He; Appeared in: IEEE Transactions on Antennas and Propagation Publication date: Oct 2017, volume: 65, issue:10, pages: 5565 - 5570 Publisher: IEEE
» Development and Characterization of an H-Shaped Microresonator Exhibiting 2:1 Internal Resonance
 Abstract:This paper reports on the design and characterization of an -shaped microresonator exhibiting nonlinear modal interactions due to 2:1 internal resonance. This has been made possible through careful design of the structure with attention to the limits of microfabricated devices. The intended nonlinear dynamics rely on the continuous transfer of energy between the anti-phase motions of two -like proof masses of the device to a mode along the orthogonal direction. Finite element and reduced order models of the structure were developed and used to design the devices with two desired flexural modes in a ~2:1 frequency ratio. The microresonator was fabricated in a commercial foundry process. Extensive experiments and transient simulations were conducted to verify the desired nonlinear responses and the models. It was demonstrated that the low-frequency mode of the device was excited through auto-parametric excitation of the higher frequency mode when the excitation level exceeded a specific threshold as expected. The device design methodologies can be employed to fabricate various sensors, including nonlinear Coriolis vibratory gyroscopes incorporating 2:1 internal resonance. [2017-0035] Autors: Atabak Sarrafan;Behraad Bahreyni;Farid Golnaraghi; Appeared in: Journal of Microelectromechanical Systems Publication date: Oct 2017, volume: 26, issue:5, pages: 993 - 1001 Publisher: IEEE
» Development and Test of a Diamond-Based Fast Neutron Detector for 200 °C Operation
 Abstract:Recent improvements in the production of artificial single-crystal diamonds have made it possible to produce commercial radiation detectors. However, the availability of diamond detectors for high-temperature and high-shock applications is limited. We have developed a compact solid-state diamond detector for high-temperature applications which require compact size, stable performance, and extreme ruggedness. It is used as a fast neutron detector for monitoring the output of a pulsed neutron generator in oil well-logging tools. The sensor consists of a high-purity monocrystalline diamond wafer with metallized electrodes on both faces. One of the metallized surfaces is mounted on a metallic plate resting on a ceramic substrate. The metallized diamond assembly is mounted in a TO-257 metal housing, which has pins connected to the two electrodes on the two faces of the diamond. The detector package, consisting of the diamond sensor and the electronics assembly, has been qualified for operation in the harsh downhole environment of oil fields. This includes high temperature and repeated shocks and vibration. Units have been tested for up to 150 h at 200 °C with no degradation in signal or count rate accuracy. The count rate accuracy with a simple detection threshold regulation scheme can reach ±1% over the range from 25 °C to 200 °C. However, this detector has applications beyond well logging, wherever there is a need for a compact, reliable detector for fast neutrons in an environment where ruggedness, exposure to high temperature, compactness, and radiation hardness are essential. Autors: Olivier Philip;Frederic Gicquel;Vincent Ernst;Zilu Zhou; Appeared in: IEEE Transactions on Nuclear Science Publication date: Oct 2017, volume: 64, issue:10, pages: 2683 - 2689 Publisher: IEEE
» Development of a 1 kW direct methanol fuel cell system [News from Japan]
 Abstract:Global warming is a matter of primary concern in the world, and therefore suppression of CO2 emission is an urgent task. It follows that mass consumption of petroleum, coal, and natural gas must be reduced, and therefore development of renewable energy sources such as wind power, solar power, and fuel cells, with less CO2 emission, is necessary. Autors: Y. Ohki; Appeared in: IEEE Electrical Insulation Magazine Publication date: Oct 2017, volume: 33, issue:5, pages: 52 - 55 Publisher: IEEE
» Development of a 1.5 kV, 1.2 kA Pulsed-Power Supply for Light Sintering
 Abstract:This paper presents the design and experimental results of the 36-kW pulsed-power supply for the xenon flash lamp. The continuous conduction mode series-parallel resonant converter is modified. This means that not only the few hundred kilohertz of high switching frequency is introduced to replace the resonant inductor with the leakage inductor of transformer but also the high output current is accomplished by using three-phase delta-connected transformers. In addition, the snubber capacitor of the inverter switches and the power factor correction module is both omitted in the compact structure. Although these main components have changed, the efficiency and power factor of the rated dummy load reach 96% and 0.96%, respectively. Within 36-kW average power, the proposed pulsed-power supply can generate as versatile combination of output pulse. For example, it can generate 20-ms pulse with 1-Hz repetition rate or generate 1-ms pulse with 20-Hz repetition rate. The used insulated gate bipolar transistor is protected from the turn-OFF peak voltage by the snubber circuit, and the effect of the snubber circuit is shown at the actual load condition. Autors: Chan-Gi Cho;Seung-Ho Song;Su-Mi Park;Hyeon-Il Park;Jung-Soo Bae;Sung-Roc Jang;Hong-Je Ryoo; Appeared in: IEEE Transactions on Plasma Science Publication date: Oct 2017, volume: 45, issue:10, pages: 2683 - 2690 Publisher: IEEE
» Development of a Novel Robotic Dolphin and Its Application to Water Quality Monitoring
 Abstract:This paper presents the mechatronic design and hydrodynamic analysis of a novel bioinspired robotic dolphin used for mobile water quality monitoring. A complementary configuration for mimicry of dolphin-like propulsion is first presented, involving a waist–fluke propulsive unit for dorsoventral oscillations and a pair of flippers with separate degree of freedom for three-dimensional (3-D) maneuvers. A host of onboard sensors is equipped to strengthen the capability of environment perception and mission execution on a near real-time basis. Considering the dynamic requirement for motion transition in water quality monitoring, a central pattern generator based controller is then built to govern the multimodal locomotion of the robotic dolphin. Moreover, a 3-D dynamic model based on the Lagrange method is employed to predict the propulsive performance, followed by simulations of continuous diving and surfacing motions. Finally, both laboratory and field experiments are conducted to demonstrate the effectiveness of the presented mechatronic design and control methods. The results further show that the robotic dolphin with 3-D maneuverability offers a feasible solution to aquatic mobile sensing. Autors: Zhengxing Wu;Jincun Liu;Junzhi Yu;Hao Fang; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 2130 - 2140 Publisher: IEEE
» Development of a Stator-Magnetless Linear Synchronous Motor for Sensorless Control
 Abstract:Sensorless control techniques that do not use a linear scale are desired for applications that require a long-stroke linear synchronous motor (LSM). This paper discusses the development of a stator-magnetless LSM (i.e., no magnet is mounted on the stator of the LSM) for sensorless control that includes a high-speed position estimation algorithm based on the magnetic saturation phenomenon. This paper presents a new structure of a flux-switching LSM that achieves a high saliency ratio using a cutout that results in magnetic saturation in the armature core. The effect of the sub-tooth on reducing the cogging thrust is also discussed. Furthermore, the analytical and experimental characteristics of inductance, thrust, cogging thrust, and sensorless drive control are discussed based on a prototype. Autors: Shogo Makino;Masanobu Kakihara;Yoshiyasu Takase;Mamoru Takaki;Toru Shikayama;Motomichi Ohto;Tsuyoshi Higuchi;Takashi Abe; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4559 - 4568 Publisher: IEEE
» Development of an Enhanced Electromagnetic Actuation System With Enlarged Workspace
 Abstract:Electromagnetic actuation is an emerging wireless control approach for manipulating magnetic microparticles for diverse minimally invasive therapy and diagnosis. This paper presents an enhanced electromagnetic manipulation system with an enlarged workspace, which is achieved by both the parametric design and the quantitative modeling of generated magnetic field of the system. The parametric design aims to characterize the influence of electromagnet parameters, such as position, radius, and height of cores on the generated electromagnetic field, so that the electromagnet specifications of the developed system can achieve a large workspace, while possessing the desired magnetic field flux density (MFFD) and gradient. With this design, the workspace of the developed prototype can reach a spherical volume with a diameter of 110 mm, the MFFD can reach 100 mT, and the gradient of MFFD can reach 2.5 T/m. The spatial distribution of electromagnetic field is quantitatively modeled using the finite-element method. Based on this model, a unit electromagnetic field distribution database for a 3-D grid of points is established. Such database enables the effective manipulation of microparticles in a considerably large workspace rather than only small central area. Experiments of manipulating paramagnetic microparticles in both 2-D and 3-D scenarios are performed to demonstrate the effectiveness of the designed system. Autors: Fuzhou Niu;Junyang Li;Weicheng Ma;Jie Yang;Dong Sun; Appeared in: IEEE/ASME Transactions on Mechatronics Publication date: Oct 2017, volume: 22, issue:5, pages: 2265 - 2276 Publisher: IEEE
» Development of LiDAR-Based UAV System for Environment Reconstruction
 Abstract:In disaster management, reconstructing the environment and quickly collecting the geospatial data of the impacted areas in a short time are crucial. In this letter, a light detection and ranging (LiDAR)-based unmanned aerial vehicle (UAV) is proposed to complete the reconstruction task. The UAV integrate an inertial navigation system (INS), a global navigation satellite system (GNSS) receiver, and a low-cost LiDAR. An unmanned helicopter is introduced and the multisensor payload architecture for direct georeferencing is designed to improve the capabilities of the vehicle. In addition, a new strategy of iterative closest point algorithm is proposed to solve the registration problems in the sparse and inhomogeneous derived point cloud. The proposed registration algorithm addresses the local minima problem by the use of direct-georeferenced points and the novel hierarchical structure as well as taking the feedback bias into INS/GNSS. The generated point cloud is compared with a more accurate one derived from a high-grade terrestrial LiDAR which uses real flight data. Results indicate that the proposed UAV system achieves meter-level accuracy and reconstructs the environment with dense point cloud. Autors: Kai-Wei Chiang;Guang-Je Tsai;Yu-Hua Li;Naser El-Sheimy; Appeared in: IEEE Geoscience and Remote Sensing Letters Publication date: Oct 2017, volume: 14, issue:10, pages: 1790 - 1794 Publisher: IEEE
» Device-Free WiFi Human Sensing: From Pattern-Based to Model-Based Approaches
 Abstract:Recently, device-free WiFi CSI-based human behavior recognition has attracted a great amount of interest as it promises to provide a ubiquitous sensing solution by using the pervasive WiFi infrastructure. While most existing solutions are pattern-based, applying machine learning techniques, there is a recent trend of developing accurate models to reveal the underlining radio propagation properties and exploit models for fine-grained human behavior recognition. In this article, we first classify the existing work into two categories: pattern-based and model-based recognition solutions. Then we review and examine the two approaches together with their enabled applications. Finally, we show the favorable properties of model-based approaches by comparing them using human respiration detection as a case study, and argue that our proposed Fresnel zone model could be a generic one with great potential for device-free human sensing using fine-grained WiFi CSI. Autors: Dan Wu;Daqing Zhang;Chenren Xu;Hao Wang;Xiang Li; Appeared in: IEEE Communications Magazine Publication date: Oct 2017, volume: 55, issue:10, pages: 91 - 97 Publisher: IEEE
» DEXTRA: A Fast Algorithm for Optimization Over Directed Graphs
 Abstract:This paper develops a fast distributed algorithm, termed DEXTRA, to solve the optimization problem when  agents reach agreement and collaboratively minimize the sum of their local objective functions over the network, where the communication between the agents is described by a directed graph. Existing algorithms solve the problem restricted to directed graphs with convergence rates of for general convex objective functions and when the objective functions are strongly convex, where  is the number of iterations. We show that, with the appropriate step-size, DEXTRA converges at a linear rate for , given that the objective functions are restricted strongly convex. The implementation of DEXTRA requires each agent to know its local out-degree. Simulation examples further illustrate our findings. Autors: Chenguang Xi;Usman A. Khan; Appeared in: IEEE Transactions on Automatic Control Publication date: Oct 2017, volume: 62, issue:10, pages: 4980 - 4993 Publisher: IEEE
» DI2S Multiswath Innovative Technique for SAR Acquisitions Optimization
 Abstract:The DIscrete stepped strip (DI2S) technique (actually patent pending) introduces an innovative method to use a synthetic aperture radar in time-sharing allowing the acquisition of different images either to increase azimuth resolution (DI2S-improved resolution) or to have a multi-image system improving the system capability and flexibility (DI2S multiswath). In this letter, the approach used by the DI2S multiswath technique will be described highlighting the main advantages in terms of performance and application. Autors: Diego Calabrese;Vanessa Mastroddi;Stefano Federici; Appeared in: IEEE Geoscience and Remote Sensing Letters Publication date: Oct 2017, volume: 14, issue:10, pages: 1820 - 1824 Publisher: IEEE
» Different Modular Techniques Applied in a Synchronous Boost Converter With SiC MOSFETs to Obtain High Efficiency at Light Load and Low Current Ripple
 Abstract:This paper is focused on a high-voltage (400 to 800 V) bidirectional converter, which is intended to be used for the interconnection of battery-based energy-storage systems with the cells of a modular multilevel converter, providing distributed energy-storage capability to a solid-state transformer. This converter must have a high efficiency at medium and light load and also a low current ripple due to the charging and discharging processes. This work takes advantage of the use of SiC MOSFETs into a synchronous boost converter to accomplish the previous requirements. First, the adoption of a variable-switching frequency control to keep the efficiency high is analyzed, and second, the use of a modular converter with different control techniques to provide a current ripple reduction is also addressed in this study. An input-parallel-output-parallel synchronous boost converter, made up with three modules (3 kW per module), is used to validate experimentally the advantages of the use of SiC MOSFETs and to compare different control techniques. Autors: Aitor Vazquez;Alberto Rodriguez;Maria R. Rogina;Diego G. Lamar; Appeared in: IEEE Transactions on Industrial Electronics Publication date: Oct 2017, volume: 64, issue:10, pages: 8373 - 8382 Publisher: IEEE
» Differential Protection in Low-Voltage Buses: An Exploration of Principles and Models
 Abstract:Current-differential principles are well known and commonly used for the protection of medium and large transformers, large motors, medium-voltage (MV) generators, MV and high-voltage buses, and any type of important power equipment with measurable input and output currents. However, is it practical to protect low-voltage (LV) distribution buses using differential protection? This article describes bus differential protection principles as well as interlocking principles for overcurrent protection. We discuss specific issues in applying differential protection in LV systems. Additionally, we present a concept of partial differential (PD) protection, which can be used in conjunction with zone-selective interlocking (ZSI) or as backup to traditional overcurrent protection to achieve high-speed and selective fault clearance. Additional concepts for the implementation of bus differential protection using networked data in LV systems are introduced. Autors: Lubomir Sevov;Marcelo Valdes; Appeared in: IEEE Industry Applications Magazine Publication date: Oct 2017, volume: 23, issue:5, pages: 28 - 39 Publisher: IEEE
» Digital Predistortion of an RF Power Amplifier Using a Reduced Volterra Series Model With a Memory Polynomial Estimator
 Abstract:A technique for reducing the number of basis waveforms used in a Volterra series model for digital predistortion (DPD) of radio frequency power amplifiers is proposed. An effective delay is defined for each basis waveform. The DPD model is constrained so that the basis waveforms used have unique delays. When several of the original Volterra terms have a common delay, they are either grouped together to form a single basis waveform or pruned to discard all but the dominant term. It is shown that grouping and pruning produce similar ACLR results when the coefficient estimator notch filters the linear signal bandwidth and applies regularization. Unique delay DPD basis sets are compatible with a fractionally sampled memory polynomial estimator. The basis waveforms within the estimator are specified in the frequency domain as a function of memoryless waveforms and delay operators, thereby reducing the number of fast Fourier transforms needed and allowing for fractional tap spacing that matches the effective delays of Volterra basis waveforms used within the DPD basis set. The approximation associated with using a memory polynomial estimator is sufficiently accurate for a closed-loop estimator to converge to a desired steady state. Autors: R. N. Braithwaite; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3613 - 3623 Publisher: IEEE
» Digital Predistortion Parameter Identification for RF Power Amplifiers Using Real-Valued Output Data
 Abstract:This brief presents a novel digital predistortion parameter identification technique that requires only the acquisition of either the in-phase (I) or the quadrature (Q) component of the power amplifier output signal. To this end, an approach that allows us to estimate the parameters of a model using only one of the IQ components of the model output is presented. Based on experimental results, it is shown that the proposed real-valued measurements-based technique can offer linearization capabilities similar to its complex-valued counterparts. The experimental results also indicate that the proposed technique can be used in combination with other techniques that focus on reducing the speed of analog-to-digital converters. Autors: Jessica Chani-Cahuana;Mustafa Özen;Christian Fager;Thomas Eriksson; Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs Publication date: Oct 2017, volume: 64, issue:10, pages: 1227 - 1231 Publisher: IEEE
» Digitally Controlled Analog Cancellation for Full Duplex Broadband Power Line Communications
 Abstract:Although in-band full-duplexing (IBFD) has long been implemented in various communication media, it was only recently that an IBFD solution was presented for broadband power line communications (BB-PLCs). The maximum attainable echo suppression using this solution is, however, limited by the dynamic range of the analog-to-digital converter (ADC). To counter this critical constraint, we propose echo cancellation in the analog domain, while persisting with a low-complexity frequency domain digital echo estimation. By formulating an expression for the number of ADC bits lost in IBFD over a conventional half-duplex operation, we show that the ADC dynamic range is no longer a limiting factor for our solution. We further extend our solution to present an analog cancellation method for multiple-input multiple-output IBFD BB-PLC systems. Finally, we present simulation results of echo cancellation and data rate gains obtained under realistic in-home BB-PLC settings, to demonstrate that our solution is capable of doubling bidirectional transfer rates in a large number of the tested network conditions. Autors: Gautham Prasad;Lutz Lampe;Sudip Shekhar; Appeared in: IEEE Transactions on Communications Publication date: Oct 2017, volume: 65, issue:10, pages: 4419 - 4432 Publisher: IEEE
» Direct Measurements of Sediment Sound Speed and Attenuation in the Frequency Band of 2–8 kHz at the Target and Reverberation Experiment Site
 Abstract:The sediment acoustic-speed measurement system is designed to measure in situ sediment sound speed and attenuation within the surficial 3 m of sediments in the frequency band of 2–8 kHz. Measurements were carried out during the Target and Reverberation EXperiment 2013 (TREX13) off Panama City, FL, USA. During TREX13, nine deployments at five selected sites were made along the 20-m isobath, termed the main reverberation track. The sediment types at the five selected sites ranged from coarse sand to a mixture of soft mud over sand, and the measured results show a spread of 80 m/s in sediment sound speed among the different types of sediments for all frequencies. Between 2–8 kHz, about 3% dispersion was observed at the sandy sites, whereas little dispersion was observed at the sites with mud. Preliminary attenuation results show 0.5–3.3 dB/m at the sandy sites, and 0.5–1.0 dB/m at the sites with mud in the same frequency band. Autors: Jie Yang;Dajun Tang; Appeared in: IEEE Journal of Oceanic Engineering Publication date: Oct 2017, volume: 42, issue:4, pages: 1102 - 1109 Publisher: IEEE
» Direct Multitype Cardiac Indices Estimation via Joint Representation and Regression Learning
 Abstract:Cardiac indices estimation is of great importance during identification and diagnosis of cardiac disease in clinical routine. However, estimation of multitype cardiac indices with consistently reliable and high accuracy is still a great challenge due to the high variability of cardiac structures and the complexity of temporal dynamics in cardiac MR sequences. While efforts have been devoted into cardiac volumes estimation through feature engineering followed by a independent regression model, these methods suffer from the vulnerable feature representation and incompatible regression model. In this paper, we propose a semi-automated method for multitype cardiac indices estimation. After the manual labeling of two landmarks for ROI cropping, an integrated deep neural network Indices-Net is designed to jointly learn the representation and regression models. It comprises two tightly-coupled networks, such as a deep convolution autoencoder for cardiac image representation, and a multiple output convolution neural network for indices regression. Joint learning of the two networks effectively enhances the expressiveness of image representation with respect to cardiac indices, and the compatibility between image representation and indices regression, thus leading to accurate and reliable estimations for all the cardiac indices. When applied with five-fold cross validation on MR images of 145 subjects, Indices-Net achieves consistently low estimation error for LV wall thicknesses (1.44 ± 0.71 mm) and areas of cavity and myocardium (204 ± 133 mm2). It outperforms, with significant error reductions, segmentation method (55.1% and 17.4%), and two-phase direct volume-only methods (12.7% and 14.6%) for wall thicknesses and areas, respectively. These advantages endow the proposed method a great potential in clinical cardiac function assessment. Autors: Wufeng Xue;Ali Islam;Mousumi Bhaduri;Shuo Li; Appeared in: IEEE Transactions on Medical Imaging Publication date: Oct 2017, volume: 36, issue:10, pages: 2057 - 2067 Publisher: IEEE
» Direct Synthesis and Design of Wideband Bandpass Filter With Composite Series and Shunt Resonators
 Abstract:In this paper, a wideband bandpass filter with composite series and shunt resonators is proposed together with a direct synthesis and design theory. The filter configuration can provide transmission zeros (TZs) on both sides of the passband. Two types of composite shunt resonators are introduced; one provides extra controllable TZs in the far stopband, whereas the other not only produces close-to-band TZs, but also high-order TZs in the far stopband in planar realization. The composite series resonator is realized by a high-impedance transmission line in shunt with a lumped capacitor. By introducing legitimate wideband circuit model approximations for the basic circuit blocks, a mixed lumped/distributed element version of the proposed filter is realized and experimentally verified. Design flexibility of circuit topology and spurious resonance suppression using TZs is discussed. Two design examples of the fifth-order and ninth-order filter prototypes are synthesized, designed, and measured, demonstrating the effectiveness of the synthesis and design theory as well as the superior performance of the proposed filter configuration. Autors: Zhiliang Li;Ke-Li Wu; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3789 - 3800 Publisher: IEEE
» Disambiguation-Free Partial Label Learning
 Abstract:In partial label learning, each training example is associated with a set of candidate labels among which only one is the ground-truth label. The common strategy to induce predictive model is trying to disambiguate the candidate label set, i.e., differentiating the modeling outputs of individual candidate labels. Specifically, disambiguation by differentiation can be conducted either by identifying the ground-truth label iteratively or by treating each candidate label equally. Nonetheless, the disambiguation strategy is prone to be misled by the false positive labels co-occurring with ground-truth label. In this paper, a new partial label learning strategy is studied which refrains from conducting disambiguation. Specifically, by adapting error-correcting output codes (ECOC), a simple yet effective approach named Pl-ecoc is proposed by utilizing candidate label set as an entirety. During training phase, to build binary classifier w.r.t. each column coding, any partially labeled example will be regarded as a positive or negative training example only if its candidate label set entirely falls into the coding dichotomy. During testing phase, class label for the unseen instance is determined via loss-based decoding which considers binary classifiers’ empirical performance and predictive margin. Extensive experiments show that Pl-ecoc performs favorably against state-of-the-art partial label learning approaches. Autors: Min-Ling Zhang;Fei Yu;Cai-Zhi Tang; Appeared in: IEEE Transactions on Knowledge and Data Engineering Publication date: Oct 2017, volume: 29, issue:10, pages: 2155 - 2167 Publisher: IEEE
» Discrete Data AGC of Hydrothermal Systems Under Varying Turbine Time Constants Along With the Power System Loading Conditions
» Dispersion Differences and Consistency of Artificial Periodic Structures
 Abstract:Dispersion differences and consistency of artificial periodic structures, including phononic crystals, elastic metamaterials, as well as periodic structures composited of phononic crystals and elastic metamaterials, are investigated in this paper. By developing a method, complex dispersion relations and group/phase velocity curves of both the single-mechanism periodic structures and the mixing-mechanism periodic structures are calculated at first, from which dispersion differences of artificial periodic structures are discussed. Then, based on a unified formulation, dispersion consistency of artificial periodic structures is investigated. Through a comprehensive comparison study, the correctness for the unified formulation is verified. Mathematical derivations of the unified formulation for different artificial periodic structures are presented. Furthermore, physical meanings of the unified formulation are discussed in the energy-state space. Autors: Zhi-Bao Cheng;Wen-Kai Lin;Zhi-Fei Shi; Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control Publication date: Oct 2017, volume: 64, issue:10, pages: 1591 - 1598 Publisher: IEEE
» Dispersion Engineering in Single-Polarization Single-Mode Photonic Crystal Fibers for a Nearly Zero Flattened Profile
 Abstract:We propose a systematic solution to the problem on dispersion engineering in single-polarization single-mode (SPSM) photonic crystal fibers (PCFs) for a nearly zero flattened profile. Based on dispersion-approximating and -normalizing methods as well as a clever engineering strategy, we have succeeded in a design of SPSM PCF with nearly zero flattened dispersion over a broad band of . Moreover, such a fiber presents a very low confinement-loss level, which is less than 0.001 dB/km over the operation band. Autors: Dunke Lu;Xiaohang Li;Guohui Zeng;Jin Liu; Appeared in: IEEE Photonics Journal Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 8 Publisher: IEEE
» Distinguishing Cloud and Snow in Satellite Images via Deep Convolutional Network
 Abstract:Cloud and snow detection has significant remote sensing applications, while they share similar low-level features due to their consistent color distributions and similar local texture patterns. Thus, accurately distinguishing cloud from snow in pixel level from satellite images is always a challenging task with traditional approaches. To solve this shortcoming, in this letter, we proposed a deep learning system to classify cloud and snow with fully convolutional neural networks in pixel level. Specifically, a specially designed fully convolutional network was introduced to learn deep patterns for cloud and snow detection from the multispectrum satellite images. Then, a multiscale prediction strategy was introduced to integrate the low-level spatial information and high-level semantic information simultaneously. Finally, a new and challenging cloud and snow data set was labeled manually to train and further evaluate the proposed method. Extensive experiments demonstrate that the proposed deep model outperforms the state-of-the-art methods greatly both in quantitative and qualitative performances. Autors: Yongjie Zhan;Jian Wang;Jianping Shi;Guangliang Cheng;Lele Yao;Weidong Sun; Appeared in: IEEE Geoscience and Remote Sensing Letters Publication date: Oct 2017, volume: 14, issue:10, pages: 1785 - 1789 Publisher: IEEE
» Distinguishing the Role of Wind in Snow Distribution by Utilizing Remote Sensing and Modeling Data: Case Study in the Northeastern Tibetan Plateau
 Abstract:Snow distribution has a profound impact on natural processes such as the hydrological cycle, the climate system, and ecological evolution. Many studies suggest that elevation, temperature, and precipitation are the three major factors controlling snow distribution. Our study explores the influence of wind on the snow distribution and finds that wind is another important factor controlling the snow distribution in the northeastern Tibet Plateau. We select the Qilian Mountains in the northeastern Tibetan Plateau as the study area, and the data include the moderate-resolution imaging spectroradiometer snow area product and the atmosphere dataset generated by the Weather Research and Forecasting model. The results indicate that there is a threshold elevation for the correlation between the fractional snow cover (FSC) area and the wind speed in the study area. At elevations above 3900 m, the FSC and wind speed exhibit a significant negative correlation, and at elevations below 3900 m, they exhibit a significant positive correlation. Our analyses indicate that the probability for the occurrence of snowdrifts is higher in regions above 3900 m and that the wind transports snow from regions above 3900 m to lower elevations. Autors: Donghang Shao;Hongyi Li;Jian Wang;Xiaoduo Pan;Xiaohua Hao; Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Publication date: Oct 2017, volume: 10, issue:10, pages: 4445 - 4456 Publisher: IEEE
» Distributed Biased Min-Consensus With Applications to Shortest Path Planning
 Abstract:Distributed consensus has been intensively studied in recent years as a means to mitigate state differences among dynamic nodes on a graph. It has been successfully employed in various applications, e.g., formation control of multirobots, load balancing, and clock synchronization. However, almost all the existing applications cast an impression of consensus as a simple process to iteratively reach agreement, without any clue on possibility to generate advanced complexity, say shortest path planning, which has been proved to be NP-hard. Counterintuitively, we show for the first time that the complexity of shortest path planning can emerge from a perturbed version of a min-consensus protocol, which as a case study may shed lights to researchers in the field of distributed control to rethink the nature of complexity and the distance between control and intelligence. Besides, we rigorously prove the convergence of graph dynamics and its equivalence to shortest path solutions. An illustrative simulation on a small-scale graph is provided to show the convergence of the biased min-consensus dynamics to shortest path solution over the graph. To demonstrate the scalability to large-scale problems, a graph with 43 826 nodes, which corresponds to a map of a maze in 2-D, is considered in the simulation study. Apart from possible applications in robot path planning, the result is further extended to robot complete coverage, showing its potential in real practice such as cleaning robots. Autors: Yinyan Zhang;Shuai Li; Appeared in: IEEE Transactions on Automatic Control Publication date: Oct 2017, volume: 62, issue:10, pages: 5429 - 5436 Publisher: IEEE
» Distributed Charging Control of Electric Vehicles Using Online Learning
 Abstract:We propose an algorithm for distributed charging control of electric vehicles (EVs) using online learning and online convex optimization. Many distributed charging control algorithms in the literature implicitly assume fast two-way communication between the distribution company and EV customers. This assumption is impractical at present and also raises security and privacy concerns. Our algorithm does not use this assumption; however, at the expense of slower convergence to the optimal solution and by relaxing the sense of optimality. The proposed algorithm requires one-way communication, which is implemented through the distribution company publishing the pricing profiles for the previous days. We provide convergence results for the algorithm and illustrate the results through numerical examples. Autors: Wann-Jiun Ma;Vijay Gupta;Ufuk Topcu; Appeared in: IEEE Transactions on Automatic Control Publication date: Oct 2017, volume: 62, issue:10, pages: 5289 - 5295 Publisher: IEEE
» Distributed Continuous-Time Algorithm for Constrained Convex Optimizations via Nonsmooth Analysis Approach
 Abstract:This technical note studies the distributed optimization problem of a sum of nonsmooth convex cost functions with local constraints. At first, we propose a novel distributed continuous-time projected algorithm, in which each agent knows its local cost function and local constraint set, for the constrained optimization problem. Then we prove that all the agents of the algorithm can find the same optimal solution, and meanwhile, keep the states bounded while seeking the optimal solutions. We conduct a complete convergence analysis by employing nonsmooth Lyapunov functions for the stability analysis of differential inclusions. Finally, we provide a numerical example for illustration. Autors: Xianlin Zeng;Peng Yi;Yiguang Hong; Appeared in: IEEE Transactions on Automatic Control Publication date: Oct 2017, volume: 62, issue:10, pages: 5227 - 5233 Publisher: IEEE
» Distributed Cooperative Reinforcement Learning-Based Traffic Signal Control That Integrates V2X Networks’ Dynamic Clustering
 Abstract:With the acceleration of urbanization in the world, urban traffic congestion has become an urgent challenge in most cities. Adaptive traffic signal control is the most approved control method to solve the problem, and accurate real-time traffic information is critical to this solution. This paper presents distributed cooperative reinforcement learning-based traffic control that integrates V2X networks’ dynamic clustering algorithm. To obtain traffic flow information accurately and instantaneously, it is important to improve the cluster stability in V2X networks. A dynamic clustering algorithm is proposed based on the enhanced affinity propagation. The proposed clustering algorithm introduces the initial cluster partition to maintain a proper cluster size and adds the lane and destination factors to improve the cluster's stability. The algorithm can provide efficient and accurate traffic state information to traffic signal controls. By integrating the clustering algorithm, a cooperative reinforcement learning control scheme is proposed to balance the traffic load. To address the tough dimensionality curse of reinforcement learning, a distributed mechanism for intersection cooperation is introduced, and a fast gradient-descent function approximation method is proposed to improve the controls’ real-time performance. The proposed intelligent traffic control scheme that integrates the stable clustering algorithm can effectively improve the traffic throughput, reduce the average waiting time, and avoid congestion. Numerical simulations on real scenarios validate the performance of the proposed approach. Autors: Weirong Liu;Gaorong Qin;Yun He;Fei Jiang; Appeared in: IEEE Transactions on Vehicular Technology Publication date: Oct 2017, volume: 66, issue:10, pages: 8667 - 8681 Publisher: IEEE
» Distributed Filtering for Switched Linear Systems With Sensor Networks in Presence of Packet Dropouts and Quantization
 Abstract:This paper is concerned with the distributed filtering problem of discrete-time switched linear systems in sensor networks in face of packet dropouts and quantization. Specifically, due to the packet dropout phenomenon, the filters may lose access to the real-time switching signal of the plant. It is assumed that the maximal packet dropout number of switching signal is bounded. Then, a distributed filtering system is proposed by further considering the quantization effect. Based on the Lyapunov stability theory, a sufficient condition is obtained for the convergence of filtering error dynamics. The filter gain design is transformed into a convex optimization problem. In this paper, a quantitative relation between the switching rule missing rate and filtering performance is established. Furthermore, the upper bound of the switching rule missing rate is also calculated. Finally, the effectiveness of the proposed filter design is validated by a simulation study on the pulse-width-modulation-driven boost converter circuit. The impact of noise covariance, system dynamics, and network connectivity is studied, and some discussions are presented on how these parameters affect the filtering performance. Autors: Dan Zhang;Zhenhua Xu;Hamid Reza Karimi;Qing-Guo Wang; Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers Publication date: Oct 2017, volume: 64, issue:10, pages: 2783 - 2796 Publisher: IEEE
» Distributed Flight Routing and Scheduling for Air Traffic Flow Management
 Abstract:Air traffic flow management (ATFM) is an important component in an air traffic control system and has significant effects on the safety and efficiency of air transportation. In this paper, we propose a distributed ATFM strategy to minimize the airport departure and arrival schedule deviations. The scheduling problem is formulated based on an en-route air traffic system model consisting of air routes, waypoints, and airports. A cell transmission flow dynamic model is adopted to describe the system dynamics under safety related constraints, such as the capacities of air routes and airports, and the aircraft speed limits. Our ATFM problem is formulated as an integer quadratic programming problem. To overcome the computational complexity associated with this problem, we first solve a relaxed quadratic programming problem by a distributed approach based on Lagrangian relaxation. Then a heuristic forward-backward propagation algorithm is proposed to obtain the final integer solution. Experimental results demonstrate the effectiveness of the proposed scheduling strategy. Autors: Yicheng Zhang;Rong Su;Qing Li;Christos G. Cassandras;Lihua Xie; Appeared in: IEEE Transactions on Intelligent Transportation Systems Publication date: Oct 2017, volume: 18, issue:10, pages: 2681 - 2692 Publisher: IEEE
» Distributed Formation Control of Networked Multi-Agent Systems Using a Dynamic Event-Triggered Communication Mechanism
 Abstract:This paper addresses the distributed formation control problem of a networked multi-agent system (MAS) subject to limited communication resources. First, a dynamic event-triggered communication mechanism (DECM) is developed to schedule inter-agent communication such that some unnecessary data exchanges among agents can be reduced so as to achieve better resource efficiency. Different from most of the existing event-triggered communication mechanisms, wherein threshold parameters are fixed all the time, the threshold parameter in the developed event triggering condition is dynamically adjustable in accordance with a dynamic rule. It is numerically shown that the proposed DECM can achieve a better tradeoff between reducing inter-agent communication frequency and preserving an expected formation than some existing ones. Second, an event-triggered formation protocol is delicately proposed by using only locally triggered sampled data in a distributed manner. Based on the formation protocol, it is shown that the state formation control problem is cast into an asymptotic stability problem of a reduced-order closed-loop system. Then, criteria for designing desired formation protocol and communication mechanism are derived. Finally, the effectiveness and advantages of the proposed approach are demonstrated through a comparative study in multirobot formation control. Autors: Xiaohua Ge;Qing-Long Han; Appeared in: IEEE Transactions on Industrial Electronics Publication date: Oct 2017, volume: 64, issue:10, pages: 8118 - 8127 Publisher: IEEE
» Distributed Learning for Energy-Efficient Resource Management in Self-Organizing Heterogeneous Networks
 Abstract:In heterogeneous networks, a dense deployment of base stations (BSs) leads to increased total energy consumption, and, consequently, increased cochannel interference (CCI). In this paper, to deal with this problem, self-organizing mechanisms are proposed, for joint channel and power allocation procedures, which are performed in a fully distributed manner. A dynamic channel allocation mechanism is proposed, in which the problem is modeled as a noncooperative game, and a no-regret learning algorithm is applied for solving the game. In order to improve the accuracy and reduce the effect of shadowing, we propose another channel allocation algorithm executed at each user equipment (UE). In this algorithm, each UE reports the channel with minimum CCI to its associated BS. Then, the BS selects its channel based on these received reports. To combat the energy consumption problem, BSs choose their transmission power by employing an on–off switching scheme. Simulation results show that the proposed mechanism, which is based on the second proposed channel allocation algorithm and combined with the on–off switching scheme, balances load among BSs. Furthermore, it yields significant performance gains up to about , , and in terms of average energy consumption, UE's rate, and BS's load, respectively, compared to a benchmark based on an interference-aware dynamic channel allocation algorithm. Autors: Atefeh Hajijamali Arani;Abolfazl Mehbodniya;Mohammad Javad Omidi;Fumiyuki Adachi;Walid Saad;Ismail Güvenç; Appeared in: IEEE Transactions on Vehicular Technology Publication date: Oct 2017, volume: 66, issue:10, pages: 9287 - 9303 Publisher: IEEE
» Distributed Scheduling and Cooperative Control for Charging of Electric Vehicles at Highway Service Stations
 Abstract:The increasing number of electric vehicles (EVs) on highways calls for the installment of adequate charging infrastructure. Since charging infrastructure has limited capacity, EVs need to wait at a charging station to get charged, and their waiting times may differ significantly from one location to another. This paper aims at developing a strategy to coordinate the queues among the charging stations, with only local information about traffic flows and the status of EV charging stations along a bidirectional highway, so that excessively long waiting times can be avoided. Specifically, a distributed algorithm is presented to schedule EV flows into neighboring charging stations, so that EVs are all appropriately served along the highway and that all the charging resources are uniformly utilized. In addition, a distributed decision making policy is developed to influence the aggregate number of EVs entering any given service station, so that each EV makes an appropriate decision (i.e., whether or not it should enter the next charging station) by contributing positively to meeting the desired queue length at service stations and by considering its own battery constraint. Performance improvement of the proposed strategy is illustrated via one of the highways in the United States, namely the Florida Turnpike. Autors: Azwirman Gusrialdi;Zhihua Qu;Marwan A. Simaan; Appeared in: IEEE Transactions on Intelligent Transportation Systems Publication date: Oct 2017, volume: 18, issue:10, pages: 2713 - 2727 Publisher: IEEE
» Distributed Simulation of Continuous Random Variables
 Abstract:We establish the first known upper bound on the exact and Wyner’s common information of continuous random variables in terms of the dual total correlation between them (which is a generalization of mutual information). In particular, we show that when the pdf of the random variables is log-concave, there is a constant gap of between this upper bound and the dual total correlation lower bound that does not depend on the distribution. The upper bound is obtained using a computationally efficient dyadic decomposition scheme for constructing a discrete common randomness variable from which the random variables can be simulated in a distributed manner. We then bound the entropy of using a new measure, which we refer to as the erosion entropy. Autors: Cheuk Ting Li;Abbas El Gamal; Appeared in: IEEE Transactions on Information Theory Publication date: Oct 2017, volume: 63, issue:10, pages: 6329 - 6343 Publisher: IEEE
 Abstract:We propose and study the application of distributed non-orthogonal multiple access (NOMA) for the uplink of cloud radio access networks. By considering that the remote radio heads are able to exchange digital information through high capacity links of the cloud, they can cooperate in performing interference cancellation, enhancing the users’ achievable rate region. The achievable rates are presented in simple closed form, while simulations show that distributed NOMA can offer substantial improvement over benchmark schemes, by exploiting the cloud capabilities. Autors: Koralia N. Pappi;Panagiotis D. Diamantoulakis;George K. Karagiannidis; Appeared in: IEEE Communications Letters Publication date: Oct 2017, volume: 21, issue:10, pages: 2274 - 2277 Publisher: IEEE
» Disturbance Estimator-Based Predictive Current Controller for Single-Phase Interconnected PV Systems
 Abstract:A digital predictive current controller for a single-phase grid-side power electronics converter employed in photovoltaic (PV) systems is presented in this paper. A disturbance estimator is employed with the controller in order to minimize its sensitivity to any parameter variation, as well as to reject grid-side disturbances. The design of the controller and the estimator are carried out using the pole placement method. The performance of the developed current controller was tested and verified experimentally using a 5.4-kW grid-connected PV system. These experiments are carried out for different levels of power delivered to the grid under different variation in the system parameters. In addition, other controllers used for interconnected PV systems are also tested to highlight the advantages of the developed current controller. The testing results illustrate the capability of the developed current controller to provide accurate, fast, and robust responses with negligible sensitivity to parameters variations and disturbances on the grid side. Autors: H. Mohomad;S. A. Saleh;L. Chang; Appeared in: IEEE Transactions on Industry Applications Publication date: Oct 2017, volume: 53, issue:5, pages: 4201 - 4209 Publisher: IEEE
» Disturbance-Observer-Based Robust Backstepping Attitude Stabilization of Spacecraft Under Input Saturation and Measurement Uncertainty
 Abstract:The problem of control input saturation and measurement uncertainties in spacecraft attitude control systems is investigated in this paper. Asymmetric limitation of the control torque and additive attitude measurement errors are considered in the backstepping attitude controller design. Stable antiwindup compensator is employed to handle the adverse effect of input saturation. The additive attitude measurement errors, external disturbances, and parametric uncertainties are compensated by the outputs of stable nonlinear disturbance observers in the robust controller design. The tuning conditions of controller parameters are derived based on the Lyapunov analysis, and it is proved that attitude, angular velocity, saturation compensator states, and disturbance observer states converge to small neighborhoods of zero. Simulation results illustrate the effectiveness of the proposed control approach. Autors: Liang Sun;Zewei Zheng; Appeared in: IEEE Transactions on Industrial Electronics Publication date: Oct 2017, volume: 64, issue:10, pages: 7994 - 8002 Publisher: IEEE
» Do We Need Minimal Solutions of Fuzzy Relational Equations in Advance?
 Abstract:Minimal solutions play a crucial role in description of all solutions to a fuzzy relational equation. The reason is that all solutions form a convex set with respect to (fuzzy) set inclusion; therefore, having all extremal solutions, we can represent the entire solution set as a union of intervals bounded from above by the greatest solution and from below by the minimal solutions. However, when computing the intervals, we obtain many duplicate solutions. The obvious question is as follows: Is there another way of representing the solution set, for instance, without the need of having all the minimal solutions in advance? We provide the positive answer to this question. Autors: Eduard Bartl;Pavel Prochazka; Appeared in: IEEE Transactions on Fuzzy Systems Publication date: Oct 2017, volume: 25, issue:5, pages: 1356 - 1363 Publisher: IEEE
» DORE: An Experimental Framework to Enable Outband D2D Relay in Cellular Networks
 Abstract:Device-to-Device (D2D) communications represent a paradigm shift in cellular networks. In particular, analytical results on D2D performance for offloading and relay are very promising, but no experimental evidence validates these results to date. This paper is the first to provide an experimental analysis of outband D2D relay schemes. Moreover, we design D2D opportunistic relay with QoS enforcement (DORE), a complete framework for handling channel opportunities offered by outband D2D relay nodes. DORE consists of resource allocation optimization tools and protocols suitable to integrate QoS-aware opportunistic D2D communications within the architecture of 3GPP Proximity-based Services. We implement DORE using an SDR framework to profile cellular network dynamics in the presence of opportunistic outband D2D communication schemes. Our experiments reveal that outband D2D communications are suitable for relaying in a large variety of delay-sensitive cellular applications, and that DORE enables notable gains even with a few active D2D relay nodes. Autors: Arash Asadi;Vincenzo Mancuso;Rohit Gupta; Appeared in: IEEE/ACM Transactions on Networking Publication date: Oct 2017, volume: 25, issue:5, pages: 2930 - 2943 Publisher: IEEE
» Dosimetric Characterization and Image Quality Assessment in Breast Tomosynthesis
 Abstract:The aim of this paper was to investigate the diagnostic potential of tomosynthesis imaging compared with the performance of 2-D digital mammography in terms of radiation dose and image quality. In particular, suitable dosimeter and phantom were used for quantifying the average glandular dose and image quality parameters, respectively. First, according to standard protocols and European guidelines, the characterization of the used tomosynthesis system was carried out to verify the reliability of characteristic parameters of the system. Successively, the absorbed dose was calculated by means of experimental measurements and the application of estimation methods. The calculated dose was then compared with the value provided by the system; this approach has confirmed the tendency of mammography equipment manufacturers to underestimate the mean glandular dose. Finally, the detection capability of different details with different contrasts was objectively assessed for both breast tomosynthesis and 2-D mammography. Autors: Gregorio Andria;Filippo Attivissimo;Attilio Di Nisio;Anna M. L. Lanzolla;Alberto Maiorana;Marco Mangiatini;Maurizio Spadavecchia; Appeared in: IEEE Transactions on Instrumentation and Measurement Publication date: Oct 2017, volume: 66, issue:10, pages: 2535 - 2544 Publisher: IEEE
» Double-Sided Design of Electrodes Driving Tunable Dielectrophoretic Miniature Lens
 Abstract:We demonstrate the design methodology, geometrical analysis, device fabrication, and testing of a double-sided design of tunable-focus dielectrophoretic liquid miniature lenses. This design is intended to reduce the driving voltage for tuning the lens, utilizing a double-sided electrode design that enhances the electric field magnitude. Fabricated devices were tested and measurements on a goniometer showed changes of up to 14° in the contact angle when the dielectrophoretic force was applied under 25 Vrms. Correspondingly, the back focal length of the liquid lens changed from 67.1 to 14.4 mm when the driving voltage was increased from 0 to 25 Vrms. The driving voltage was significantly lower than those previously reported with similar device dimensions using single-sided electrode designs. This design allows for a range of both positive and negative menisci dependent on the volume of the lens liquid initially dispensed. [2017-0011] Autors: Yousuf D. Almoallem;Hongrui Jiang; Appeared in: Journal of Microelectromechanical Systems Publication date: Oct 2017, volume: 26, issue:5, pages: 1122 - 1131 Publisher: IEEE
» Double-Sided Parallel-Strip Line Resonator for Dual-Polarized 3-D Frequency-Selective Structure and Absorber
 Abstract:Double-sided parallel-strip line (DSPSL) resonator is employed in the unit cell (UC) of a 3-D frequency-selective structure (3-D FSS) in order to exhibit the desired response (bandstop, bandpass, and absorption) under an incident wave of arbitrary polarization. It is found that this UC supports the propagation of three quasi-TEM modes. The first and third modes are concentrated in the substrate and air regions of the UC, respectively. While the second mode is concentrated in the interface between air and substrate of the UC, the polarization of the second mode is perpendicular to the polarization of the first and third modes. Detailed analysis of these propagating modes is provided with equivalent circuit models to explain the operating principle. A dual-polarized bandstop 3-D FSS is then proposed. It exhibits a stable frequency response with a constant out-of-band bandwidth under a large range of oblique incidence angle. A dual-polarized absorber is also realized employing a UC with DSPSL resonator. By properly exciting and absorbing the second mode of the modified UC, an ultra-wideband absorber is constructed, which has −10 dB fractional bandwidth of 148% from 1.51 to 10.1 GHz with an absorber thickness of at the lowest absorption frequency. Autors: Ahmed Abdelmottaleb Omar;Zhongxiang Shen; Appeared in: IEEE Transactions on Microwave Theory and Techniques Publication date: Oct 2017, volume: 65, issue:10, pages: 3744 - 3752 Publisher: IEEE
» Downlink Coverage Analysis for a Finite 3-D Wireless Network of Unmanned Aerial Vehicles