Electrical and Electronics Engineering publications abstract of: 11-2017 sorted by title, page: 1

» A Hysteretic Switched-Capacitor DC–DC Converter With Optimal Output Ripple and Fast Transient Response
Abstract:
Hysteretic control is popular for switched-capacitor (SC) dc–dc converters. Conventional hysteretic controllers require either a large output capacitor or high-speed output voltage detection for proper regulation. In this paper, a lower boundary hysteretic control method is proposed which matches the output sampling frequency to the converter switching frequency across the entire load range, hence optimal output voltage ripple can be achieved. The converter responses instantly to step-up load transients that are smaller than six times the initial load current. When larger load transient step occurs, the sampling frequency jumps to its maximum value to recover the output voltage quickly. Small output voltage droop can be achieved while using an output capacitance value on the same order as the converter’s charge transferring capacitance. A 1/2 step-down SC dc–dc converter with the proposed control technique is fabricated in 0.18- CMOS process. The converter achieves a peak efficiency of 86.4% and delivers a maximum output power of 5 mW.
Autors: Zhekai Xiao;Anh Khoa Bui;Liter Siek;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Nov 2017, volume: 25, issue:11, pages: 2995 - 3005
Publisher: IEEE
 
» A Ka-Band Waveguide Magic-T With Coplanar Arms Using Ridge-Waveguide Transition
Abstract:
A Ka-band waveguide magic-T with coplanar arms is presented in this letter. By using an E-plane power divider and a ridge-waveguide transition, the four arms of the magic-T are placed in the same plane, which greatly simplifies the assembly. Compared to the previous method utilizing a microstrip-to-waveguide transition, the structure proposed in this letter achieved a higher power-handling capability because of all-metal elements. Over the frequency band of 28 to 36 GHz, the measured return loss of the input port and the isolation between the opposite ports are greater than 20 dB, indicating good characteristics of the proposed structure.
Autors: Yin-Jian He;Da-Yi Mo;Qiong-Sen Wu;Qing-Xin Chu;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Nov 2017, volume: 27, issue:11, pages: 965 - 967
Publisher: IEEE
 
» A Kernel-Based Low-Rank (KLR) Model for Low-Dimensional Manifold Recovery in Highly Accelerated Dynamic MRI
Abstract:
While many low rank and sparsity-based approaches have been developed for accelerated dynamic magnetic resonance imaging (dMRI), they all use low rankness or sparsity in input space, overlooking the intrinsic nonlinear correlation in most dMRI data. In this paper, we propose a kernel-based framework to allow nonlinear manifold models in reconstruction from sub-Nyquist data. Within this framework, many existing algorithms can be extended to kernel framework with nonlinear models. In particular, we have developed a novel algorithm with a kernel-based low-rank model generalizing the conventional low rank formulation. The algorithm consists of manifold learning using kernel, low rank enforcement in feature space, and preimaging with data consistency. Extensive simulation and experiment results show that the proposed method surpasses the conventional low-rank-modeled approaches for dMRI.
Autors: Ukash Nakarmi;Yanhua Wang;Jingyuan Lyu;Dong Liang;Leslie Ying;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Nov 2017, volume: 36, issue:11, pages: 2297 - 2307
Publisher: IEEE
 
» A Kernel-Power-Density-Based Algorithm for Channel Multipath Components Clustering
Abstract:
Cluster-based channel modeling has been an important trend in the development of channel model, as it maintains accuracy while reducing complexity. Whereas a large number of channel measurements have shown that multipath components (MPCs) are distributed as groups, i.e., clusters, existing clustering algorithms have various drawbacks with respect to complexity, threshold choices, and/or assumptions about prior knowledge. In this paper, a kernel-power-density (KPD)-based algorithm is proposed for MPC clustering. It uses the kernel density of MPCs to incorporate the modeled behavior of MPCs and takes into account the power of the MPCs. Furthermore, the KPD algorithm only considers the nearest MPCs in the density estimation to better identify the local density variations of MPCs. A heuristic approach of cluster merging is used to improve the performance. Both simulation and channel measurements validate the KPD algorithm, and almost no performance degradation is found even with a large number of clusters and large cluster angular spread, which outperforming other algorithms. The KPD algorithm enables applications in multiple-input-multiple-output channels with no prior knowledge about the clusters, such as number and initial locations. It also has a fairly low computational complexity and can be used for cluster-based channel modeling.
Autors: Ruisi He;Qingyong Li;Bo Ai;Yang Li-Ao Geng;Andreas F. Molisch;Vinod Kristem;Zhangdui Zhong;Jian Yu;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Nov 2017, volume: 16, issue:11, pages: 7138 - 7151
Publisher: IEEE
 
» A Large-Scale Emulation System for Realistic Three-Dimensional (3-D) Forest Simulation
Abstract:
The realistic reconstruction and radiometric simulation of a large-scale three-dimensional (3-D) forest scene have potential applications in remote sensing. Although many 3-D radiative transfer models concerning forest canopy have been developed, they mainly focused on homogeneous or relatively small heterogeneous scenes, which are not compatible with the coarse-resolution remote sensing observations. Due to the huge complexity of forests and the inefficiency of collecting precise 3-D data of large areas, realistic simulation over large-scale forest area remains challenging, especially in regions of complex terrain. In this study, a large-scale emulation system for realistic 3-D forest Simulation is proposed. The 3-D forest scene is constructed from a representative single tree database (SDB) and airborne laser scanning (ALS) data. ALS data are used to extract tree height, crown diameter and position, which are linked to the individual trees in SDB. To simulate the radiometric properties of the reconstructed scene, a radiative transfer model based on a parallelized ray-tracing code was developed. This model has been validated with an abstract and an actual 3-D scene from the radiation transfer model intercomparison website and it showed comparable results with other models. Finally, a 1 km 1 km scene with more than 100 000 realistic individual trees was reconstructed and a Landsat-like reflectance image was simulated, which kept the same spatial pattern as the actual Landsat 8 image.
Autors: Jianbo Qi;Donghui Xie;Dashuai Guo;Guangjian Yan;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Nov 2017, volume: 10, issue:11, pages: 4834 - 4843
Publisher: IEEE
 
» A Level-Set-Based Image Assimilation Method: Potential Applications for Predicting the Movement of Oil Spills
Abstract:
In this paper, we present a novel method for assimilating geometric information from observed images. Image assimilation technology fully utilizes structural information from the dynamics of the images to retrieve the state of a system and thus to better predict its evolution. Level-set method describing the evolution of the geometry shapes of a given system is taken into account to include the dynamics of the images. This method takes advantage of Lagrangian information in an Eulerian numerical framework. In our numerical experiments, we apply this state-of-the-art technique to a pollutant transport problem, to calibrate the initial contours of pollutants and to identify diffusion coefficients of the model. It can be shown a potential approach for oil spills, because topological merging and breaking of oil slicks are well defined and easily performed by this proposed approach. Numerical results show that the proposed method is visibly efficient compared with the classical method based on the concentration map when the concentration measurements and the background fields are not well available.
Autors: Long Li;François-Xavier Le Dimet;Jianwei Ma;Arthur Vidard;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Nov 2017, volume: 55, issue:11, pages: 6330 - 6343
Publisher: IEEE
 
» A Lightweight Masked AES Implementation for Securing IoT Against CPA Attacks
Abstract:
A false key-based advanced encryption standard (AES) technique is proposed to prevent the stored secret key leaking from the substitution-box under correlation power analysis (CPA) attacks without significant power and area overhead. Wave dynamic differential logic (WDDL)-based XOR gates are utilized during the reconstruction stage to hide the intermediate data that may be highly correlated with the false key. After applying the false key and designing the reconstruction stage with the WDDL, the minimum measurement-to-disclose value for the proposed lightweight masked AES engine implementation becomes over 150 million against CPA attacks. As compared to an unprotected AES engine, the power, area, and performance overhead of the proposed AES implementation is negligible.
Autors: Weize Yu;Selçuk Köse;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Nov 2017, volume: 64, issue:11, pages: 2934 - 2944
Publisher: IEEE
 
» A Line Flow Granular Computing Approach for Economic Dispatch With Line Constraints
Abstract:
Line flow calculation plays a critically important role to guarantee the stable operation of power system in economic dispatch (ED) problems with line constraints. This paper presents a line flow granular computing approach for power flow calculation to assist the investigation on ED with line constraints, where the hierarchy method is adopted to divide the power network into multiple layers to reduce computational complexity. Each layer contains granules for granular computing, and the layer network is reduced by Ward equivalent retaining the PV nodes and boundary nodes of tie lines to decrease the data dimension. Then, Newton–Raphson method is applied further to calculate the power line flows within the layer. This approach is tested on IEEE 39-bus and 118-bus systems. The testing results show that the granular computing approach can solve the line flow problem in 9.2 s for the IEEE 118-bus system, while the conventional AC method needs 44.56 s. The maximum relative error of the granular computing approach in line flow tests is only 0.43%, which is quite small and acceptable. Therefore, the case studies demonstrate that the proposed granular computing approach is correct, effective, and can ensure the accuracy and efficiency of power line flow calculation.
Autors: Xueping Li;Liangxing Fang;Zhigang Lu;Jiangfeng Zhang;Hao Zhao;
Appeared in: IEEE Transactions on Power Systems
Publication date: Nov 2017, volume: 32, issue:6, pages: 4832 - 4842
Publisher: IEEE
 
» A Link Between CBRAM Performances and Material Microscopic Properties Based on Electrical Characterization and Atomistic Simulations
Abstract:
In this paper, we investigate the link between various resistive memory (RRAM) electrical characteristics: endurance, window margin (WM), and retention. For this purpose, several RRAMs are characterized using various resistive layers and bottom electrodes. By focusing on one technology and optimizing programming conditions (current, voltage, and time), we establish a tradeoff between endurance and WM. Then, by changing memory stack, we demonstrate the correlation between endurance plus window marging improvement and retention degradation. Studying this last feature from a material point of view, we analyze different oxides by density functional theory. We realize a systematic review for possible exchanges of species between resistive layer and Cu-based top electrode and study their diffusion. This provides insights on conductive filament composition in different stacks. Combining previous experiments and simulations, we propose a link between memory characteristics and material microscopic parameters, through the ion energy migration barrier. Finally, we extract how endurance, WM, and retention are correlated to material properties and electrical parameters in order to choose the suitable material for a defined application using the RRAM technology.
Autors: Cécile Nail;Gabriel Molas;Philippe Blaise;Benoit Sklenard;Remy Berthier;Mathieu Bernard;Luca Perniola;Gérard Ghibaudo;Christophe Vallée;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Nov 2017, volume: 64, issue:11, pages: 4479 - 4485
Publisher: IEEE
 
» A Low Area Overhead NBTI/PBTI Sensor for SRAM Memories
Abstract:
Bias temperature instability (BTI) is known as one serious reliability concern in nanoscale technologies. BTI gradually increases the absolute value of threshold voltage () of MOS transistors. The main consequence of shift of the SRAM cell transistors is the static noise margin (SNM) degradation. The SNM degradation of SRAM cells results in bit-flip occurrences due to transient faults and should be monitored accurately. This paper proposes a sensor called write current-based BTI sensor (WCBS) to assess the BTI-aging state of SRAM cells. The WCBS measures BTI-induced SNM degradation of SRAM cells by monitoring the maximum write current shifts due to BTI. The observations show that the maximum current consumption during write operation is an effective identifier to measure and SNM shifts. The granularity of BTI assessment of one cell up to a row of memory can be achieved by writing special bit patterns on the memory block during the test. We evaluated the sensor through SPICE-level simulations in 32-nm technology size. The precision of WCBS is about ±1.25 mV (±3.2% error). One sensor is enough for the entire SRAM memory block with negligible area/power overhead; less than 1%. The effects of process variation and temperature changes on WCBS are investigated in detail.
Autors: Maryam Karimi;Nezam Rohbani;Seyed-Ghassem Miremadi;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Nov 2017, volume: 25, issue:11, pages: 3138 - 3151
Publisher: IEEE
 
» A Low Turn-Off Loss 4H-SiC Trench IGBT With Schottky Contact in the Collector Side
Abstract:
In this paper, a 4H-SiC trench insulated gate bipolar transistor (IGBT) incorporating a Schottky contact in the collector side is proposed to reduce the turn-off energy loss. The proposed structure is explored and compared with the conventional IGBT using ATLAS. The simulation results have indicated that the reduction in turn-off energy loss is more than 88%, with a slight degradation in the – characteristics. Concurrently, with the same on-state voltage drop, the turn-off loss is reduced by a figure of 84%.
Autors: Yan-Juan Liu;Ying Wang;Yue Hao;Jun-Peng Fang;Chan Shan;Fei Cao;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Nov 2017, volume: 64, issue:11, pages: 4575 - 4580
Publisher: IEEE
 
» A Low-Cost Lane-Determination System Using GNSS/IMU Fusion and HMM-Based Multistage Map Matching
Abstract:
This paper presents a low-cost real-time lane-determination system that fuses micro-electromechanical systems inertial sensors (accelerometers and gyroscopes), global navigation satellite system (GNSS), and commercially available road network maps. The system can be used for intelligent transportation systems, telematics applications, and autonomous driving. The system does not depend on visual markings or highly precise GNSS technology, such as DGPS or RTK, and it does not need explicit lane-level resolution maps. High-resolution estimation of the vehicle’s position, velocity, and orientation is implemented by fusing inertial sensors with GNSS in a loosely coupled mode using extended Kalman filter. A curve-to-curve road-level map-matching is implemented using a hidden Markov model followed by a least-square regression step that estimates the vehicle’s lane. The system includes a lane-change detector based on inertial sensors and the filtered vehicle’s state. The system has been realized in real time and tested extensively on real-road data. Experiments showed robust map-matching in challenging road intersections and a 97.14% lane-determination success rate.
Autors: Mohamed Maher Atia;Allaa R. Hilal;Clive Stellings;Eric Hartwell;Jason Toonstra;William B. Miners;Otman A. Basir;
Appeared in: IEEE Transactions on Intelligent Transportation Systems
Publication date: Nov 2017, volume: 18, issue:11, pages: 3027 - 3037
Publisher: IEEE
 
» A Low-Energy Machine-Learning Classifier Based on Clocked Comparators for Direct Inference on Analog Sensors
Abstract:
This paper presents a system, where clocked comparators consuming only energy directly derive classification decisions from analog sensor signals, thereby replacing instrumentation amplifiers, ADCs, and digital MACs, as typically required. A machine-learning algorithm for training the classifier is presented, which enables circuit non-idealities as well as severe energy/area scaling in analog circuits to be overcome. Furthermore, a noise model of the system is presented and experimentally verified, providing a means to predict and optimize classification error probability in a given application. The noise model shows that superior noise efficiency is achieved by the comparator-based system compared with a system based on linear low-noise amplifiers. A prototype in 130-nm CMOS performs image recognition of handwritten numerical digits, by taking raw analog pixels as the inputs. Due to pin limitations on the chip, the images with pixels are resized and downsampled to give 47 pixel features, yielding an accuracy of 90% for an ideal ten-way classification system (MATLAB simulated). The prototype comparator-based system achieves equivalent performance with a total energy of 543 pJ per ten-way classification at a rate up to 1.3 M images per second, representing lower energy than an ADC/digital-MAC system.
Autors: Zhuo Wang;Naveen Verma;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Nov 2017, volume: 64, issue:11, pages: 2954 - 2965
Publisher: IEEE
 
» A Low-Power CMOS Crystal Oscillator Using a Stacked-Amplifier Architecture
Abstract:
This paper presents a low-power 39.25-MHz crystal oscillator with a new stacked-amplifier architecture achieving the smallest figure of merit (FoM) ever reported for a crystal oscillator for wireless communications. Theoretical analyses of the power consumption and the phase noise (PN) in the proposed stacked-amplifier architecture are newly provided to clarify the reason why the proposed stacked-amplifier architecture achieves the smallest FoM. Additionally, a new self-forward-body-biasing technique and flicker noise suppression technique are shown to reduce the minimum operational supply voltage (VDD(MIN)) and the PN, respectively. The proposed 3.3-V, 39.25-MHz stacked-amplifier crystal oscillator fabricated in a 65-nm CMOS process exhibits the smallest FoM for a crystal oscillator of −248 dBc/Hz with a power consumption of 19 and PN of −139 dBc/Hz at 1-kHz offset frequency. The relative frequency errors among 11 samples at temperatures of −30 °C to 80 °C and for ±10% supply voltage variation are ±10.5 ppm and ±0.12 ppm, respectively. The long-term frequency error is −0.98 ppm in the first year (=365 days).
Autors: Shunta Iguchi;Takayasu Sakurai;Makoto Takamiya;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Nov 2017, volume: 52, issue:11, pages: 3006 - 3017
Publisher: IEEE
 
» A Low-Power High-Speed Hybrid ADC With Merged Sample-and-Hold and DAC Functions for Efficient Subranging Time-Interleaved Operation
Abstract:
An 8-bit 1-GS/s hybrid analog-to-digital converter (ADC) for high-speed low-power applications is introduced. It has a subranging architecture with a 3-bit flash ADC as a first stage and a 5-bit four-channel time-interleaved comparator-based asynchronous binary search (CABS) ADC as a second stage. In each channel, a merged sample-and-hold and capacitive digital-to-analog converter (SHDAC) performs the sampling and residue generation for the subranging operation. The effects of the parasitic capacitances on the SHDAC linearity are analyzed, and a linearity correction method is introduced to enable power-efficient high-speed operation in the presence of parasitics because the design approach allows reducing the sampling capacitance in the SHDAC. Furthermore, the sampling network configuration incorporates an error reduction technique to alleviate the clock feedthrough of bootstrap switches. The offsets of the comparators in the flash ADC are calibrated using a built-in reference signal via an extra sampling channel. According to postlayout simulations at 1 GS/s in 130-nm CMOS, the ADC has an effective number of bits higher than 7.37 bits up to the Nyquist frequency while consuming 13.3 mW from a 1.2-V supply.
Autors: Seyed Alireza Zahrai;Marina Zlochisti;Nicolas Le Dortz;Marvin Onabajo;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Nov 2017, volume: 25, issue:11, pages: 3193 - 3206
Publisher: IEEE
 
» A Low-Profile Wideband Substrate-Integrated Waveguide Cavity-Backed E-Shaped Patch Antenna for the Q-LINKPAN Applications
Abstract:
A low-profile substrate-integrated waveguide cavity-backed E-shaped patch antenna is proposed for the Q-LINKPAN application in this paper. In order to expand the operating bandwidth, a co-planar waveguide (CPW) is used to feed the proposed antenna with a metallized via for generating one more resonant mode. In addition, a substrate-integrated cavity is employed to suppress the surface wave and improve the radiation efficiency. A differential feeding network is used in the design to improve the symmetry of the E-plane radiation pattern and the H-plane cross polarization. A prototype is designed, fabricated, and measured for a demonstration. The measured results show that the prototype has a 10 dB impedance bandwidth of 34.4%, a gain of around 12.5 dBi with a narrow E-plane radiation beam within 37.5–46 GHz for long distance applications, and a gain of around 8 dBi with a broad E-plane radiation beam within 47–53 GHz for short distance applications. The proposed technique can be used to develop compact planar antenna for meeting both the short- and long-rang communication requirements of the emerging Q-LINKPAN wireless system.
Autors: Kuikui Fan;Zhang-Cheng Hao;Quan Yuan;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5667 - 5676
Publisher: IEEE
 
» A Machine Learning-Based ETA Estimator for Wi-Fi Transmissions
Abstract:
Recent advancements related to device to device (D2D) communication make it possible for a transmitting node to dynamically select the interface to be used for data transfers locally, without traversing any network infrastructure. In this scenario, a controller is identified, whose goal is to manage the D2D connection after its establishment. The software defined networking paradigm makes it possible to select this controller node via software: a device becomes the master node of a Wi-Fi-direct network, whereas the remaining units, i.e., the clients, can exchange data with other devices through the master. This paper develops a machine learning-based prediction algorithm for the aforementioned scenario, in which multiple elements, while receiving data from the controller, require an accurate on-the-fly estimation of the remaining transmission time, i.e., the estimated time of arrival. Different machine learning approaches are considered for this task, with the goal of exploiting only the information available at each client, without modifying any standard communication protocol. This information is critical when, for instance, a mobile user needs to decide whether or not to delay a data transfer, based on the load of the network and on the residual time under radio coverage from an access point.
Autors: Davide Del Testa;Matteo Danieletto;Michele Zorzi;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Nov 2017, volume: 16, issue:11, pages: 7011 - 7024
Publisher: IEEE
 
» A Major Player: Renewables Are Now Mainstream [Guest Editorial]
Abstract:
The Utility Variable-Generation Integration Group (UVIG) has focused on the integration of wind, and more recently solar, power into electric power systems. The industry focus is now concentrating around how to integrate inverter-based power plants into weak grids and, indeed, how to design a grid for 100% nonsynchronous generation. The focus is no longer on how to integrate those alien forms of generation from Mars into the grid but how to integrate the energy systems of the future, of which renewable energy systems are a major part, into a coherent whole. Examines how this will likely develop over the coming years.
Autors: J. Charles Smith;
Appeared in: IEEE Power and Energy Magazine
Publication date: Nov 2017, volume: 15, issue:6, pages: 16 - 21
Publisher: IEEE
 
» A Method for Accurate Parameter Estimation of Series Compensated Transmission Lines Using Synchronized Data
Abstract:
Power system software used for analysis and dynamic simulation and relay settings require accurate model parameters of different elements for precise results. For this, transmission line parameter verification is necessary at times, which changes due to atmospheric condition and aging. This paper presents a method for estimating the parameters of series compensated line online using synchronized time-domain data captured by the intelligent electronic devices at both ends of the line, which is free of the compensation model. The method uses traveling waves generated during disturbance to obtain the propagation constant of the line, which is used to estimate the resistance and the characteristic impedance of the line. Subsequently, the inductance and capacitance of the line are calculated. The proposed method is tested using PSCAD/EMTDC simulation data of an actual series compensated line in Indian power grid. Results demonstrate the accuracy of the proposed method.
Autors: Swaroop Gajare;Ashok Kumar Pradhan;Vladimir Terzija;
Appeared in: IEEE Transactions on Power Systems
Publication date: Nov 2017, volume: 32, issue:6, pages: 4843 - 4850
Publisher: IEEE
 
» A Mid-Infrared Fiber-Coupled QEPAS Nitric Oxide Sensor for Real-Time Engine Exhaust Monitoring
Abstract:
We report the development and application of a compact and sensitive mid-infrared nitric oxide (NO) sensor using off-beam quartz-enhanced photoacoustic spectroscopy (QEPAS). This QEPAS sensor exploits the strong absorption band of NO at using a distributed-feedback quantum cascade laser (QCL). The QCL was connected with the custom-designed photoacoustic gas cell with a mid-infrared multimode fiber to form a plug-and-play system. The selection of key sensor parameters, such as micro-resonator, laser modulation depth, and gas pressure, was discussed in detail about improving the detection sensitivity. With a minimum detection limit of 120 ppbv, our QEPAS NO sensor was deployed in real-time diesel-engine exhaust monitoring. We observed the influence of soot existing in the engine exhaust on the sensor performance, which was filtered by a high efficiency particulate arrestance material. Our sensor captured the varied NO concentrations between 126 and 187 ppmv in the exhaust at different engine rotational speeds.
Autors: Chao Shi;Dien Wang;Zhen Wang;Liuhao Ma;Qiang Wang;Ke Xu;Shih-Chi Chen;Wei Ren;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7418 - 7424
Publisher: IEEE
 
» A Miniaturized Force Sensor Based on Hair-Like Flexible Magnetized Cylinders Deposited Over a Giant Magnetoresistive Sensor
Abstract:
The detection of force with higher resolution than observed in humans (~1 mN) is of great interest for emerging technologies, especially surgical robots, since this level of resolution could allow these devices to operate in extremely sensitive environments without harming these. In this paper, we present a force sensor fabricated with a miniaturized footprint (9 mm2), based on the detection of the magnetic field generated by magnetized flexible pillars over a giant magnetoresistive sensor. When these flexible pillars deflect due to external loads, the stray field emitted by these will change, thus varying the GMR sensor resistance. A sensor with an array of five pillars with diameter and 1 mm height was fabricated, achieving a 0 to 26 mN measurement range and capable of detecting a minimum force feature of . A simulation model to predict the distribution of magnetic field generated by the flexible pillars on the sensitive area of the GMR sensor in function of the applied force was developed and validated against the experimental results reported in this paper. The sensor was finally tested as a texture classification system, with the ability of differentiating between four distinct surfaces varying between 0 and root mean square surface roughness.
Autors: Pedro Ribeiro;Mohammed Asadullah Khan;Ahmed Alfadhel;Jürgen Kosel;Fernando Franco;Susana Cardoso;Alexandre Bernardino;José Santos-Victor;Lorenzo Jamone;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» A More National Technology
Abstract:
Over the past several decades, many computer societies have begun to focus on IT, leaving computer science behind.
Autors: David Alan Grier;
Appeared in: Computer
Publication date: Nov 2017, volume: 50, issue:11, pages: 77 - 77
Publisher: IEEE
 
» A Multi-Objective Routing Strategy for QoS and Energy Awareness in Software-Defined Networks
Abstract:
Energy consumption is a key concern in the deployment and operation of current data networks, for which software-defined networks (SDNs) have become a promising alternative. Although several works have been proposed to improve the energy efficiency, these techniques may lead to performance degradations when QoS requirements are neglected. Inspired by this problem, this letter introduces a new routing strategy, jointly considering QoS requirements and energy awareness in SDN with in-band control traffic. To that end, we present a complete formulation of the optimization problem and implement a multi-objective evolutionary algorithm. Simulation results validate the performance improvement on critical network parameters.
Autors: Adriana Fernández-Fernández;Cristina Cervelló-Pastor;Leonardo Ochoa-Aday;
Appeared in: IEEE Communications Letters
Publication date: Nov 2017, volume: 21, issue:11, pages: 2416 - 2419
Publisher: IEEE
 
» A Multi-Platform Lab for Teaching and Research in Active Distribution Networks
Abstract:
Today's electricity paradigm requires that the notion of active distribution systems be introduced at both undergraduate and graduate curricula. This involves not only the customary theoretical foundations but also a suitable power engineering laboratory, where flexible enough and affordable resources allow students and researchers to carry out hands-on experiments reinforcing the concepts explained in the classroom. This paper describes the smart grid laboratory of the Power Engineering Group at the University of Seville, composed of a scaled-down distribution system, along with the required control and monitoring equipment, designed to help its users easily grasp the major influence that distributed generation and storage devices exert in the operation of medium-voltage distribution systems.
Autors: José María Maza-Ortega;Manuel Barragán-Villarejo;Francisco de Paula García-López;Juan Jiménez;Juan Manuel Mauricio;Lázaro Alvarado-Barrios;Antonio Gómez-Expósito;
Appeared in: IEEE Transactions on Power Systems
Publication date: Nov 2017, volume: 32, issue:6, pages: 4861 - 4870
Publisher: IEEE
 
» A Multispectral 3-D Vision System for Invertebrate Detection on Crops
Abstract:
Real-time detection and identification of invertebrates on crops is a necessary capability for integrated pest management, however, this challenging task has not been well-solved. Multispectral or hyperspectral machine vision systems have shown advantages for efficient and accurate detection and identification of certain invertebrate pests. However, only using spectral information has limited the capability for detection, especially for some camouflaged pests on host plants. Three-dimensional (3-D) object representations are being intensively studied for multiview object recognition and scene understanding in many fields. However, because of the lack of proper data collection methods and robust algorithms, 3-D technologies have not yet attained applications for detecting invertebrates. We have developed a multispectral 3-D vision system, which can create denser point clouds of plants and pests using the multispectral images of ultraviolet, blue, green, red, and near-infrared. An algorithm named local variance of normals was designed, which can distinguish broad leaves from relatively larger pests in noisy point clouds. The vision system could aid integrated pest management systems for pest monitoring, or could be used as a sensor of an automatic pesticide sprayer.
Autors: Huajian Liu;Sang-Heon Lee;Javaan Singh Chahl;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7502 - 7515
Publisher: IEEE
 
» A New Approach for Detecting Urban Centers and Their Spatial Structure With Nighttime Light Remote Sensing
Abstract:
Urban spatial structure affects many aspects of urban functions and has implications for accessibility, environmental sustainability, and public expenditures. During the urbanization process, a careful and efficient examination of the urban spatial structure is crucial. Different from the traditional approach that relies on population or employment census data, this research exploits the nighttime light (NTL) intensity of the earth surface recorded by satellite sensors. The NTL intensity is represented as a continuous mathematical surface of human activities, and the elemental features of urban structures are identified by analogy with earth’s topography. We use a topographical metaphor of a mount to identify an urban center or subcenter and the surface slope to indicate an urban land-use intensity gradient. An urban center can be defined as a continuous area with higher concentration or density of employments and human activities. We successfully identified 33 urban centers, delimited their corresponding boundaries, and determined their spatial relations for Shanghai metropolitan area, by developing a localized contour tree method. In addition, several useful properties of the urban centers have been derived, such as 9% of Shanghai administrative area has become urban centers. We believe that this method is applicable to other metropolitan regions at different spatial scales.
Autors: Zuoqi Chen;Bailang Yu;Wei Song;Hongxing Liu;Qiusheng Wu;Kaifang Shi;Jianping Wu;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Nov 2017, volume: 55, issue:11, pages: 6305 - 6319
Publisher: IEEE
 
» A New Concept for a Flat Lens Design Using Dielectric Cylinders
Abstract:
A new design method called the array scattering method for a flat lens made of dielectric cylinders is presented. The method reconstructs the far-field radiation pattern of a 2-D arbitrary geometrical shape dielectric scatterer. Since the method has no restrictions on the near field, it allows us to alter the polarization currents distribution in order to obtain a better far-field performance for a periodic structure with a given unit cell size. The method also allows us to perform a simple parametric study on the limits of the unit cell size, taking into account the scatterer geometrical dimensions. This parameter (unit cell size) does not appear in the formulation if we use a method that assumes an infinite array of cylinders. The realization is done using the multiple scattering method, which is one of the most accurate methods to deal with arrays scattering. Nevertheless, the method is almost entirely analytic, not iterative and does not require multiple simulations in order to obtain the required objective.
Autors: Eran Falek;Reuven Shavit;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5720 - 5731
Publisher: IEEE
 
» A New Dynamic Complex Baseband Pulse Compression Method for Chirp-Coded Excitation in Medical Ultrasound Imaging
Abstract:
Chirp-coded excitation can increase the signal-to-noise ratio (SNR) without degrading the axial resolution. Effective pulse compression (PC) is important to maintain the axial resolution and can be achieved with radio frequency (RF) and complex baseband (CBB) data (i.e., and , respectively). can further reduce the computational complexity compared to ; however, suffers from a degraded SNR due to tissue attenuation. In this paper, we propose a new dynamic CBB PC method ( that can improve the SNR while compensating for tissue attenuation. The compression filter coefficients in the method are generated by dynamically changing the demodulation frequencies along with the depth. For PC, the obtained coefficients are independently applied to the in-phase and quadrature components of the CBB data. To evaluate the performance of the proposed method, simulation, phantom, and in vivo studies were conducted, and all three studies showed improved SNR, i.e., maximally 3.87, 7.41, and 5.75 dB, respectively. In addition, the measured peak range sidelobe level of the proposed method yielded lower value- than the and , and it also derived a suitable target location, i.e., a <0.07-mm target location error, while maintaining the axial resolution. In an in vivo abdominal experiment, the method depicted brighter and clearer features in the hyperechoic region because highly correlated signals were produced by compensating for tissue attenuation. These results demonstrated that the proposed method can improve the SNR of chirp-coded excitation while preserving the axial resolution and the target location and reducing the computational complexity.
Autors: Jinbum Kang;Yeajin Kim;Wooyoul Lee;Yangmo Yoo;
Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Publication date: Nov 2017, volume: 64, issue:11, pages: 1698 - 1710
Publisher: IEEE
 
» A New Efficient Thickness Profile Design Method for Streamlined Airborne Radomes
Abstract:
The streamlined shapes of airborne radomes tend to cause severe degradation of the electromagnetic (EM) performance, which can be compensated by properly designing the radome thickness profile. Conventional variable thickness radomes based on optimization method yield excellent EM performance at the expense of 1) considerable design time consumed by the inevitable optimization process and 2) potential manufacturing difficulties as thickness profile tends to vary dramatically in the entire range of the radome. In this communication, we present an efficient thickness profile design method through introducing the concept of half-wave thickness under average incident angle. No optimization process is involved and gentle thickness profile variation is naturally guaranteed by the gradual variation of radome shape which determines the average incident angle. Both 2-D and 3-D cases are considered in computing the average incident angle. Results of a tangent-ogival airborne radome validate the effectiveness of the proposed method.
Autors: Wanye Xu;B. Y. Duan;Peng Li;Yuanying Qiu;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 6190 - 6195
Publisher: IEEE
 
» A New Electric Magnetic-Geared Machine for Electric Unmanned Aerial Vehicles
Abstract:
This paper proposes a new electric magnetic-geared (EMG) machine, which artfully incorporates the magnetic gear into an outer-rotor inserted permanent-magnet (PM) machine, purposely for electric unmanned aerial vehicle (e-UAV) application. The proposed EMG machine artfully shares the sandwiched-rotor for both the PM machine and the magnetic gear. As a result, the proposed machine can run in the high speed and high power for propelling the e-UAV. The design details, operation principles, static characteristics, and machine performances, as well as the propulsion performances of the proposed machine, are elaborated and discussed. The finite-element method is utilized to verify the validity of the machine design and performances, with emphasis on the e-UAV application.
Autors: Chunhua Liu;Jincheng Yu;Christopher H. T. Lee;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» A New Family of Exponential-Based High-Order DGTD Methods for Modeling 3-D Transient Multiscale Electromagnetic Problems
Abstract:
A new family of exponential-based time integration methods are proposed for the time-domain Maxwell’s equations discretized by a high-order discontinuous Galerkin (DG) scheme formulated on locally refined unstructured meshes. These methods, which are developed from the Lawson method, remove the stiffness on the time explicit integration of the semidiscrete operator associated with the fine part of the mesh, and allow for the use of high-order time explicit scheme for the coarse part operator. They combine excellent stability properties with the ability to obtain very accurate solutions even for very large time step sizes. Here, the explicit time integration of the Lawson-transformed semidiscrete system relies on a low-storage Runge-Kutta (LSRK) scheme, leading to a combined Lawson-LSRK scheme. In addition, efficient techniques are presented to further improve the efficiency of this exponential-based time integration. For the efficient calculation of matrix exponential, we employ the Krylov subspace method. Numerical experiments are presented to assess the stability, verify the accuracy, and numerical convergence of the Lawson-LSRK scheme. They also demonstrate that the DG time-domain methods based on the proposed time integration scheme can be much faster than those based on classical fully explicit time stepping schemes, with the same accuracy and moderate memory usage increase on locally refined unstructured meshes, and are thus very promising for modeling 3-D multiscale electromagnetic problems.
Autors: Hao Wang;Li Xu;Bin Li;Stéphane Descombes;Stéphane Lantéri;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5960 - 5974
Publisher: IEEE
 
» A New Hybrid Permanent Magnet Synchronous Motor With Two Different Rotor Sections
Abstract:
In this paper, a new hybrid permanent magnet (PM) synchronous motor with two-part rotor is proposed. The new motor is composed of surface mounted and interior magnet rotor segments on a stepped skewed shaft. The hybrid topology has wider constant power speed ratio than conventional surface mounted PM motors with relatively the same torque density. No-load and on-load finite-element analyses (FEA) are performed independently for both surface PM and interior PM synchronous motor. Superposition of the results is gathered to obtain the actual performance of the hybrid motor. The 2-D FEA results with skewed models are also performed at the final stage of the design. A prototype motor is manufactured and experimental results are obtained. Good agreement is observed between the simulations and test data for the proposed motor.
Autors: Oguzhan Ocak;Metin Aydin;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» A New Interval Pattern Analysis Method of Array Antennas Based on Taylor Expansion
Abstract:
In this communication, a new Taylor expansion-based interval pattern analysis method is developed to predict the impact of the small excitation amplitude uncertainty on the radiated array pattern. The dependence problem of the classical interval arithmetic, which may lead to overestimation of performance intervals, is addressed in this communication. The proposed method approximates by approximating the antenna power values to the first order with respect to the uncertain amplitude. The new method is simpler and can produce more accurate bounds of the antenna pattern and the pattern features than the existing techniques. Several representative numerical examples are investigated to demonstrate the validity and efficiency of the proposed method.
Autors: Naigang Hu;Baoyan Duan;Wanye Xu;Jinzhu Zhou;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 6151 - 6156
Publisher: IEEE
 
» A New Ka-Band Doppler Radar in Robust and Precise Cardiopulmonary Remote Sensing
Abstract:
In this paper, a new Ka-band Doppler radar with an ability to remotely monitor respiration rate, heartbeat rate (HR), and heart rate variability (HRV) is presented. Exploiting the advantage of high sensitivity of Ka-band radar in sensing of chest-wall movement, we make more accurate reconstruction of cardiopulmonary activities from low-quality received signal. The advantage of using Ka-band radar is obtained by paying a penalty, which is harmonic interferences that make measuring of cardiopulmonary details infeasible in lots of real scenarios. In this paper, by using a more complete model of return signal, a new routine is introduced for the robust detection of breathing and HR that extremely alleviates the problems associated with harmonic interferences. Besides, a more suitable model is proposed, which can cover time-variability cardiorespiratory features. Taking advantage of this model and based on the unconditional orthonormal representation of band-limited signals, a filter with time-varying coefficients is proposed to extract HRV. This extraction is done without resorting to tracking HR trace that makes it more precise and robust than the conventional approach. The indicated filter enables us to suggest a novel approach to remove random body motion effects. By experimental data, the applicability of the new radar for a wide range of real world scenarios is investigated, and its advantages beside conventional approaches are proved practically in different aspects.
Autors: Seyed Mohammad Ali Tayaranian Hosseini;Hamidreza Amindavar;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Nov 2017, volume: 66, issue:11, pages: 3012 - 3022
Publisher: IEEE
 
» A New Method for Neural Spike Alignment: The Centroid Filter
Abstract:
Recordings made directly from the nervous system are a key tool in experimental electrophysiology and the development of bioelectronic medicines. Analysis of these recordings involves the identification of signals from individual neurons, a process known as spike sorting. A critical and limiting feature of spike sorting is the need to align individual spikes in time. However, electrophysiological recordings are made in extremely noisy environments that seriously limit the performance of the spike-alignment process. We present a new centroid-based method and demonstrate its effectiveness using deterministic models of nerve signals. We show that spike alignment in the presence of noise is possible with a 30 dB reduction in minimum SNR compared with the conventional methods. We present a mathematical analysis of the centroid method, characterizing its fundamental operation and performance. Furthermore, we show that the centroid method lends itself particularly well to hardware realization, and we present results from a low-power implementation that operates on an FPGA, consuming ten times less power than conventional techniques - an important property for implanted devices. Our centroid method enables the accurate alignment of spikes in sub-0 dB SNR recordings and has the potential to enable the analysis of spikes in a wider range of environments than has been previously possible. Our method thus has the potential to influence significantly the design of electrophysiological recording systems in the future.
Autors: Benjamin W. Metcalfe;Christopher T. Clarke;Nick Donaldson;John Taylor;
Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Publication date: Nov 2017, volume: 25, issue:11, pages: 1988 - 1997
Publisher: IEEE
 
» A New Methodology for Mining Frequent Itemsets on Temporal Data
Abstract:
Temporal data contain time-stamping information that affects the results of data mining. Traditional techniques for finding frequent itemsets assume that datasets are static and the induced rules are relevant across the entire dataset. However, this is not the case when data is temporal. In this paper, we are trying to improve the efficiency of mining frequent itemsets on temporal data. Since patterns can hold in either all or some of the intervals, we propose a new algorithm to restrict time intervals, which is called frequent itemset mining with time cubes. Our focus is developing an efficient algorithm for this mining problem by extending the well-known a priori algorithm. The notion of time cubes is proposed to handle time hierarchies. This is the way by which the patterns that happen periodically, during a time interval or both, are recognized. A new density threshold is also proposed to solve the overestimating problem of time periods and also make sure that discovered patterns are valid. We evaluate our algorithms via experiments.
Autors: Mazaher Ghorbani;Masoud Abessi;
Appeared in: IEEE Transactions on Engineering Management
Publication date: Nov 2017, volume: 64, issue:4, pages: 566 - 573
Publisher: IEEE
 
» A New Mover Separated Linear Magnetic-Field Modulated Motor for Long Stroke Applications
Abstract:
Linear magnetic-field modulated (LMFM) motor exhibits high thrust force by effectively employing the magnetic-field modulation effect. In this paper, a new mover separated LMFM (MS-LMFM) motor is proposed, which successfully alleviates the space confliction between permanent magnets (PMs) and windings in the existing LMFM motor. The structure and the operation principle of the existing and proposed motor are described, and the major design parameters are optimized for maximum thrust force. Moreover, electromagnetic performances of both motors are compared by finite-element method. Theoretical and simulation analysis shows that the proposed motor can exhibit enhanced force performance than the existing one under fixed copper loss. Simultaneously, reduced iron and PM losses can also be obtained by proposed motor. Finally, a 3-D modeling MS-LMFM motor is built for a global observation of motor structure and further verification of the 2-D analysis.
Autors: Wenxiang Zhao;Shiyuan Wang;Jinghua Ji;Liang Xu;Zhijian Ling;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» A New Nine-Phase Permanent Magnet Synchronous Motor With Consequent Pole Rotor for High-Power Traction Applications
Abstract:
Although three-phase permanent magnet (PM) motors are quite common in industry, multi-phase PM motors are used in special applications where high power and redundancy are required. Multi-phase PM motors offer higher torque/power density than conventional three-phase PM motors. In this paper, a novel multi-phase consequent pole PM (CPPM) synchronous motor is proposed. The constant power–speed range of the proposed motor is quite wide as opposed to conventional PM motors. The design and the detailed finite-element analysis of the proposed nine-phase CPPM motor and performance comparison with a nine-phase surface mounted PM motor are completed to illustrate the benefits of the proposed motor.
Autors: M. Onsal;Y. Demir;M. Aydin;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» A New Optimization Model for Reliable Team Formation Problem Considering Experts’ Collaboration Network
Abstract:
The objective of this study is to propose a new optimization model for the formation of a reliable team of experts, who have a certain number of skills and best collaboration with each other. The proposed mathematical model maximized team reliability by considering the probability of unreliable experts that may leave the team with the probability (1-Q) and proposed a backup for each unreliable member. In this paper, a new model was developed for simultaneously forming a team with three key factors: 1) expert's skills; 2) expert's collaboration network; and 3) expert's reliability. This model was evaluated by two numerical studies on both artificial and real-life datasets with small and big data. The optimum combination of team members with regard to skills, collaboration network, and reliability will help managers in performing their projects or operations. Therefore, the new optimization model, called the reliable team formation problem, proposed team members in two sets consisting of main and backup members.
Autors: Mohammad Fathian;Mohamad Saei-Shahi;Ahmad Makui;
Appeared in: IEEE Transactions on Engineering Management
Publication date: Nov 2017, volume: 64, issue:4, pages: 586 - 593
Publisher: IEEE
 
» A New Sensitive Excitation Technique in Nondestructive Inspection for Underground Pipelines by Using Differential Coils
Abstract:
In general, a magnetic flux leakage (MFL) pipeline inspection gauge (PIG) has been applied to nondestructive testing for investigating ferromagnetic materials, such as underground gas pipelines. Although MFL PIG is efficient to the inter-city large-scale pipelines, it is hard to apply to small-size pipelines that are usually installed in the city, because the permanent magnet for MFL PIG is too big and heavy to operate inside the small pipe. The strong adhesive magnetic force of permanent magnet to the pipe wall also prevents the usage of MFL PIG in small pipelines. In this paper, we propose a new technology of nondestructive inspection by using a differential coil, which is easy to be manufactured with lightweight, low cost, and simple structure for operating inside the underground pipelines. Comparing with the conventional permanent-magnet MFL PIG, the results of the proposed system could also maximize the detection sensitivity of defect signals and minimize the magnetic adhesive force on the pipe wall simultaneously.
Autors: Hui Min Kim;Gwan Soo Park;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A New Unsupervised Hyperspectral Band Selection Method Based on Multiobjective Optimization
Abstract:
Unsupervised band selection methods usually assume specific optimization objectives, which may include band or spatial relationship. However, since one objective could only represent parts of hyperspectral characteristics, it is difficult to determine which objective is the most appropriate. In this letter, we propose a new multiobjective optimization-based band selection method, which is able to simultaneously optimize several objectives. The hyperspectral band selection is transformed into a combinational optimization problem, where each band is represented by a binary code. More importantly, to overcome the problem of unique solution selection in traditional multiobjective methods, we develop a new incorporated rank-based solution set concentration approach in the process of Tchebycheff decomposition. The performance of our method is evaluated under the application of hyperspectral imagery classification. Three recently proposed band selection methods are compared.
Autors: Xia Xu;Zhenwei Shi;Bin Pan;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Nov 2017, volume: 14, issue:11, pages: 2112 - 2116
Publisher: IEEE
 
» A Noise-Efficient 36 nV/ $surd $ Hz Chopper Amplifier Using an Inverter-Based 0.2-V Supply Input Stage
Abstract:
This paper presents an analog front end (AFE) that achieves a high noise efficiency by using a chopper amplifier with a 0.2-V supply inverter-based input stage followed by a 0.8-V supply stage. The high input-stage current needed to reduce the input-referred noise is drawn from the 0.2-V supply, significantly reducing power consumption. The 0.8 V stage provides high gain and signal swing, improving linearity. Biasing and common-mode rejection techniques for the ultra-low-voltage stage are presented. The AFE is implemented in a 0.18 CMOS process and integrates the chopper low-noise instrumentation amplifier, a programmable-gain amplifier, and an antialiasing filter. The AFE consumes 0.79 and achieves a competitive power efficiency factor (PEF) of 1.6 and an input noise of 0.94 integrated from 0.5 to 670 Hz while maintaining a 36 nV/Hz input noise density down to 0.5 Hz. The included 0.8/0.2-V buck converter may be used to provide the 0.2-V supply at 72%–74% efficiency without significantly increasing noise, yielding a PEF of 1.8.
Autors: Frank M. Yaul;Anantha P. Chandrakasan;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Nov 2017, volume: 52, issue:11, pages: 3032 - 3042
Publisher: IEEE
 
» A Nonlinear State Estimator-Based Decentralized Secondary Voltage Control Scheme for Autonomous Microgrids
Abstract:
This study proposes a fully decentralized secondary voltage control scheme which employs the state estimation method in autonomous microgrids. Based on a large-signal dynamic model of a microgrid, a linear parameter varying based state estimator that is localized in each distributed generation (DG) unit serves as an alternative communication role and obtains the dynamics of the other DG units independently. A linear matrix inequality formulation for pole placement condition is derived for the state estimator design. A decentralized secondary voltage controller is, thus, able to achieve accurate reactive power sharing and average voltage restoration without any additional communication links. Our approach offers superior reliability, flexibility, and economic efficiency because of the irrelevance of communications to its performance, which is essential when conventional centralized or distributed methods are likely to yield towards poor performance or even instability under communication latency or data drop-out conditions. Simulation results that verify the effectiveness of the proposed methodology are provided.
Autors: Wei Gu;Guannan Lou;Wen Tan;Xiaodong Yuan;
Appeared in: IEEE Transactions on Power Systems
Publication date: Nov 2017, volume: 32, issue:6, pages: 4794 - 4804
Publisher: IEEE
 
» A Nonparametric Statistical Technique for Modeling Overland TMI (2A12) Rainfall Retrieval Error
Abstract:
In this letter, we evaluate a nonparametric error model for Tropical Rainfall Measurement Mission (TRMM) passive microwave (PMW) rainfall (2A12) product over coverage in the southern continental United States, and assess the impact of surface soil moisture information on the model’s performance. Reference precipitation was based on high-resolution (5 min/1 km) rainfall fields derived from the NOAA/National Severe Storms Laboratory multiradar multisensor system. The error model was evaluated using a K-fold validation experiment using systematic and random error statistics of the model-adjusted TRMM Microwave Imager rainfall point estimates, and ensemble verification statistics of the corresponding prediction intervals. Results show better performance, particularly in the accuracy of the prediction intervals, when near-surface soil moisture was used as input parameter. The error model can be extended using the TRMM and Global Precipitation Measurement satellite missions’ precipitation radar rainfall and satellite soil moisture data sets to characterize globally the uncertainty of PMW products.
Autors: M. A. E. Bhuiyan;E. N. Anagnostou;P.-E. Kirstetter;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Nov 2017, volume: 14, issue:11, pages: 1898 - 1902
Publisher: IEEE
 
» A Note on Parallel Asynchronous Channels With Arbitrary Skews
Abstract:
A zero-error coding scheme of asymptotic rate was recently described for a communication channel composed of parallel asynchronous lines satisfying the so-called no switch assumption. We prove that this is in fact the highest rate attainable, i.e., the zero-error capacity of this channel.
Autors: Mladen Kovačević;
Appeared in: IEEE Transactions on Information Theory
Publication date: Nov 2017, volume: 63, issue:11, pages: 7320 - 7321
Publisher: IEEE
 
» A Novel 3-D Concentric-Winding-Type Three-Phase Variable Inductor for Reactive Power Compensation in Electric Power Systems
Abstract:
A variable inductor consists of a magnetic core, primary dc windings, and secondary ac windings. The effective inductance of the secondary ac winding can be controlled by the primary dc current because of its nonlinear magnetic characteristic. Hence, variable inductors can be applied as a reactive power compensator for voltage stabilization in electric power systems, and have desirable features such as a simple and robust structure, low cost, and high reliability. In a previous paper, a concentric-winding-type three-phase variable inductor with a 2-D structure has been proposed. It was demonstrated that the 2-D variable inductor has good controllability and a low distortion current. To further increase productivity and reduce costs, this paper presents a novel concentric-winding-type three-phase variable inductor with a 3-D structure. It is demonstrated that the leakage flux of the proposed 3-D variable inductor is reduced by more than 30%. Furthermore, a 6.6 kV–100 kVA 3-D variable inductor is designed and compared to its 2-D counterpart. It is proved that eddy current loss, which is induced within an oil-immersed self-cooled tank because of leakage flux from the variable inductor, can be reduced to one-third of that of the 2-D variable inductor.
Autors: Kenji Nakamura;Yuta Yamada;Ryusei Nono;Takashi Ohinata;Kenji Arimatsu;Osamu Ichinokura;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Novel Approach for 2-D Electromagnetic Field Analysis of Surface Mounted Permanent Magnet Synchronous Motor Taking Into Account Axial End Leakage Flux
Abstract:
This paper proposes a novel approach for electromagnetic field analysis of surface-mounted permanent synchronous machines taking into account axial end leakage flux. In order to calculate the axial end leakage flux using the 2-D finite-element analysis (FEA), the leakage magnetic flux in the axial direction is reflected to the 2-D model by applying the permeability factor into the slot area. The permeability factor is derived by the equivalent magnetic circuit method. At this time, the permeability factor is calculated by considering the main leakage path in the slot and the leakage path in the axial direction of air region. The effectiveness of the proposed method is verified by comparing the results of the proposed method with the experimental results as well as the conventional 2-D FEA results and the 3-D FEA results.
Autors: Jae-Woo Jung;Hyung-Il Park;Jung-Pyo Hong;Byeong-Hwa Lee;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Novel Approach for Plastic-Bonded Magnets of the Type MQU-F Melt Spun NdFeGaB-Type Alloys
Abstract:
Permanent magnets have attracted research interest in the last decades as they are used in a wide range of applications, in consumer electronics, motors, electric generators, and nano-micro scale applications [microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS)]. Plastic-bonded magnets (PBMs)—composites with permanent magnetic powder embedded in a polymer binder—are considered among the most innovative methods of manufacturing magnets at lower temperatures than conventional methods. In this framework, plastic-bonded NdFeGaB magnets were prepared through a novel “high-density PBM” approach and their structural and magnetic properties are presented in this paper. High densities of the order 82% of the theoretical estimated density value were achieved opening a new path toward permanent magnets applications.
Autors: S. Karamanou;M. Gjoka;E. Devlin;V. Psycharis;A. Ioannidou;G. Giannopoulos;D. Niarchos;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 3
Publisher: IEEE
 
» A Novel Approach for QoS-Aware Joint User Association, Resource Block and Discrete Power Allocation in HetNets
Abstract:
We consider joint optimization of user-to-base-station (BS) association, and time-frequency resource block (RB) and power allocation in heterogeneous networks (HetNets). The objective is to develop a design: 1) that maximizes the number of users accommodated in the network while satisfying their quality of service demands and 2) that minimizes usage of the resources required to meet these demands. We investigate two novel instances of HetNets with opportunistic RB-reuse. In the first instance, user-to-BS associations and power allocations can be time-shared, and the RBs can be reused during the signaling interval. For this instance, it is shown that the design problem can be approximated by a problem that yields tight convex upper and lower bounds on the objective. In contrast, the second instance represents a case in which the RBs can be reused, but the user-to-BS associations and power allocations are not time-shared, and hence, fixed throughout the signaling interval. The latter case gives rise to a combinatorial optimization problem, which we provide an approximate solution for by using a polynomial-complexity two-phase approach based on semidefinite relaxation with randomization.
Autors: Hamza Umit Sokun;Ramy H. Gohary;Halim Yanikomeroglu;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Nov 2017, volume: 16, issue:11, pages: 7603 - 7618
Publisher: IEEE
 
» A Novel Asymmetric and Unconventional Stator Winding Configuration and Placement for a Dual Three-Phase Surface PM Motor
Abstract:
Multi-phase permanent magnet (PM) motors are becoming more popular because of their higher torque densities, enhanced efficiency, and fault-tolerant capabilities. In this paper, a novel six-phase PM synchronous motor with a new asymmetric stator ac winding scheme and placement is proposed. Two identical dual three-phase asymmetrical winding sets are placed in two separate half of the stator in 180 mechanical degrees. This approach reduces the phase resistance and thus copper losses. Torque quality of the proposed motor is also analyzed using 2-D finite element method in detail. It can be concluded that the proposed novel asymmetric stator has more advantages to offer than conventional six-phase PM motors.
Autors: Y. Demir;M. Aydin;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» A Novel Boresight and Conical Pattern Reconfigurable Antenna With the Diversity of 360° Polarization Scanning
Abstract:
A novel design of boresight and conical pattern reconfigurable antenna with the capability of 360° polarization scanning is presented in this paper. At boresight mode, the antenna produces a continuously reconfigurable polarization over 360° in the azimuth plane, which provides adaptive-polarization reception between a transmitter and a receiver. The antenna is analyzed in terms of the electric field with an explanation of the generation of TM11 and TM02 resonant modes, which provides an innovative method of designing pattern reconfigurable antennas for the WLAN applications. The proposed method is validated by a good agreement between simulation and experimental results for an antenna designed to provide boresight and conical pattern switching at 2.4 GHz. The gain of 6.05 dBi and efficiency of 86.7% are measured in the boresight mode, corresponding to 4.39 dBi and 82.4% at conical mode.
Autors: Yang Yang;Roy B. V. B. Simorangkir;Xi Zhu;Karu Esselle;Quan Xue;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5747 - 5756
Publisher: IEEE
 
» A Novel Conflict-Free Parallel Memory Access Scheme for FFT Processors
Abstract:
This brief presents a novel conflict-free access scheme for memory-based fast Fourier transform (FFT) processors. It is proved to satisfy the constraints of the mixed-radix, continuous-flow, parallel-processing, and variable-size FFT computations. An address generation unit is also designed and outperforms existing architectures with reduced gate delay and lower hardware complexity.
Autors: Qian-Jian Xing;Zhen-Guo Ma;Ying-Ke Xu;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Nov 2017, volume: 64, issue:11, pages: 1347 - 1351
Publisher: IEEE
 
» A Novel Consequent-Pole Hybrid Excited Vernier Machine
Abstract:
This paper proposes a novel consequent-pole hybrid excited vernier machine (CPHEVM) by combining hybrid excited concept and vernier structure, and the consequent-pole magnet arrangement is employed on outer rotor. The proposed machine can achieve high torque density at low speed and excellent flux-weakening capability at high speed, which are highly desirable for electric vehicle applications. The direct current field windings are embedded between modulating poles, which increase the space utilization ratio to enable flux regulation without decreasing torque capability. The configuration, operation principle, and design consideration of the proposed CPHEVM are described, respectively. Finite-element method is employed to analyze the electromagnetic performance of the selected CPHEVMs with various slot/pole combinations, including flux regulation capability, back-electromagnetic force, and torque characteristics with and without flux-weakening control.
Autors: Haitao Wang;Shuhua Fang;Hui Yang;Heyun Lin;Dong Wang;Yibo Li;Chenxiao Jiu;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Novel Deep Embedding Network for Building Shape Recognition
Abstract:
Building shape, as a key structured element, plays a significant role in various urban remote sensing applications. However, because of high complexity and intraclass variations between building structures, the capability of building shape description and recognition becomes limited or even impoverished. In this letter, a novel deep embedding network is proposed for building shape recognition, which combines the strength of the unsupervised feature learning of convolutional neural networks (CNNs) and a novel triplet loss. Specifically, we take advantage of the strong discriminative power of CNNs to learn an efficient building shape representation for shape recognition. With this deep embedding network, the high-dimensional image space can be mapped into a low-dimensional feature space, and the deep features can effectively reduce the intraclass variations while increasing the interclass variation between different building shape images. Afterward, the derived deep features are exploited for the process of building shape recognition. This method consists of two stages. In the first stage, for standard building shape image queries stored in the shape primitives library and the building shape data set, two sets of deep features are extracted with the deep embedding network. In the second stage, we formulate the shape recognition task into a feature matching problem and the final building shape recognition results can be achieved by set-to-set feature matching method. Experiments on the VHR-10 and UCML data sets demonstrate the effectiveness and precision of the proposed method.
Autors: Shu Tian;Ye Zhang;Junping Zhang;Nan Su;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Nov 2017, volume: 14, issue:11, pages: 2127 - 2131
Publisher: IEEE
 
» A Novel Design of the Rotary Electromagnetic Actuator and the Analysis of Critical Demagnetization State for Its Permanent Magnet
Abstract:
The rotary type electromagnetic actuator is often used in the electromagnetic mechanical components design, such as high-sensibility switch, signal electromagnetic relay, and so on. This type of actuator is required to have high conversion speed and action frequency, high signal reliability, and low power consumption per volume. In this paper, a new type of rotary electromagnetic actuator with permanent magnet (PM) is designed. Based on the polarity characteristics of PM, a couple of coils are designed in diagonal direction. A flux guide path is designed to optimize the magnetic circuit. PM is applied as the armature, and the electromagnetic system and the contact system are designed individually, which can achieve a high level maximum space utilization. In order to study the characteristic of PM, the PM is divided into several subsections. The migration analysis of the working point based on analytic model is carried on for the selection of PM, and the precise static characteristics of the actuator are analyzed by the finite-element model. The prototype actuator is assembled and tested, and the advantages of fast conversion speed and high reliability is verified by the test.
Autors: You Jiaxin;Wang Ruichao;Chen Hao;Chen Feng;Liang Huimin;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» A Novel Dual-Stator Vernier Permanent Magnet Machine
Abstract:
Vernier permanent magnet (VPM) machines for direct-drive applications are receiving more and more attention due to its small pulsating torque, high torque density at low rotation speed. This paper proposes a novel VPM machine, which has two stators and a sandwiched rotor. The outer stator is a conventional stator with three-phase windings and semi-closed slots, and the inner stator has an iron core and PMs mounted on the surface of it. The rotor has a consequent-pole structure with Halbach-array PMs. In this paper, the operation principles and the feasible slot-pole combinations of the proposed machine are analyzed. Moreover, to verify the superior performances of the proposed VPM machine, it is compared with a regular VPM machine in terms of back electromotive force, average torque, pulsating torque, power factor, efficiency, and overload capabilities. It shows that the proposed machine has higher torque density, larger efficiency, and lower cogging torque.
Autors: Yuting Gao;Ronghai Qu;Dawei Li;Haiyang Fang;Jian Li;Wubin Kong;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» A Novel Framework for Motion-Tolerant Instantaneous Heart Rate Estimation by Phase-Domain Multiview Dynamic Time Warping
Abstract:
Objective: long-term wearable instantaneous heart rate (IHR) monitoring is essential to enable pervasive heart health and fitness management. In this paper, a novel framework is proposed to robustly estimate the IHR from electrocardiogram (ECG) signals corrupted by large amounts of daily motion artifacts, which are one of the major impediments against the long-term IHR monitoring. Methods: the corrupted ECG signals are first projected to a high-dimensional phase space, where the constructed phase portraits of heartbeats are of many new geometrical properties and are expected to be powerful patterns more immune to the motion artifacts. Afterwards, a multiview dynamic time warping approach is applied on the constructed phase portraits, to effectively capture motion artifacts-induced inconsistencies and reveal heartbeats-related consistencies from corrupted signals. Finally, the phase portraits of heartbeats in the multidimensional phase space can be identified, and then, the IHR estimates are achieved. Results: the proposed framework is evaluated on a wrist-ECG dataset acquired by a semicustomized platform and also a public ECG dataset. With a signal-to-noise ratio as low as −9 dB, the mean absolute error and root mean square error of the estimated IHR are 2.5 beats per minute (BPM) and 7.0 BPM, respectively. Conclusion: these results demonstrate that our framework can effectively identify the heartbeats from ECG signals continuously corrupted by intense and random motion artifacts and estimate the IHR. Significance: the proposed framework greatly outperforms previously reported approaches and is expected to contribute to long-term IHR monitoring.
Autors: Qingxue Zhang;Dian Zhou;Xuan Zeng;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Nov 2017, volume: 64, issue:11, pages: 2562 - 2574
Publisher: IEEE
 
» A Novel Hydrazine Electrochemical Sensor Based on Gold Nanoparticles Decorated Redox-Active 2-Amino-4H-Chromene-3-Carbonitrile
Abstract:
This paper describes the synthesis and application of a new carbonitrile derivative in order to determine hydrazine. First, 2-amino-4H-chromene-3-carbonitrile molecules were immobilized on the cleaned surface of the electrode. Then, the nano-sized gold nanoparticles were electrochemically synthesized on the surface of this carbonitrile layer (AuNPs/AHC/GCE). The surface morphology authenticated that gold nanoparticles and AHC satisfactorily covered the surface of the electrode. The AuNPs/AHC/GCE acted as a sensor for the electrocatalytic determination of hydrazine. In fact, the presence of AHC and AuNPs reduced the oxidation potential of hydrazine with a significant increase in its oxidation current. In optimal conditions, the calibration plot of electrocatalytic current versus hydrazine concentration showed two dynamic ranges, 5.0–1.970 mmol L−1 and 1.970–11.768 mmol L−1, with a low detection limit of 20.0 nmol L−1. Finally, the effect of various species was investigated in hydrazine determination, and the results showed that this method is applicable in detecting hydrazine in water and urine samples with high selectivity and sensitivity. Au nanoparticles, Glassy carbon electrode, Hydrazine, 2-amino-4H-chromene-3-carbonitrile.
Autors: Masoumeh Taei;Hossein Salavati;Seyed Hossein Banitaba;Leili Shahidi;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7325 - 7331
Publisher: IEEE
 
» A Novel Linear Permanent Magnet Vernier Machine With Consequent-Pole Permanent Magnets and Halbach Permanent Magnet Arrays
Abstract:
The linear permanent magnet (PM) vernier machine (LPMVM) can reach a higher thrust density at low speed compared to the regular linear PM machines due to the utilization of the magnetic gear effect, which makes it a good solution for low-speed direct-drive applications. In order to further improve the machine thrust density, a novel LPMVM with consequent-pole and Halbach PM array is proposed and optimized in this paper. Then, in order to show the superior thrust performance of the proposed LPMVM, it is compared to two conventional LPMVMs in terms of back electric motive force (back EMF), thrust force, and power factor. It is found that machine no-load back EMF can be improved by 72.5% and its thrust density is 46% higher than that of the conventional LPMVM.
Autors: Chaojie Shi;Dawei Li;Ronghai Qu;He Zhang;Yuting Gao;Yongsheng Huo;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Novel Markov Chain Based ILC Analysis for Linear Stochastic Systems Under General Data Dropouts Environments
Abstract:
This technical note contributes to the convergence analysis for iterative learning control (ILC) for linear stochastic systems under general data dropout environments, i.e., data dropouts occur randomly at both the measurement and actuator sides. Data updating in the memory array is arranged in such a way that data at every time instance is updated independently, which allows successive data dropouts both in time and iteration axes. The update mechanisms for both the computed input and real input are proposed and then the update process of both inputs is shown to be a Markov chain. By virtue of Markov modeling, a new analysis method is developed to prove the convergence in both mean square and almost sure senses. An illustrative example verifies the theoretical results.
Autors: Dong Shen;Jian-Xin Xu;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Nov 2017, volume: 62, issue:11, pages: 5850 - 5857
Publisher: IEEE
 
» A Novel Meander-Line Polarizer Modeling Procedure and Broadband Equivalent Circuit
Abstract:
A new modeling approach for the design of planar multilayered meander-line polarizers is presented. For the first time a multielement equivalent circuit is adopted to characterize the meander-line unit cell. This equivalent circuit significantly improves the bandwidth performance with respect to the state-of-the-art. In addition to this, a polynomial interpolation matrix approach is employed to take into account the dependence on the meander-line geometrical parameters. This leads to an accuracy comparable to that of a full-wave analysis. At the same time, the computational cost is minimized so as to make this model suitable for real-time tuning and fast optimizations. A four-layer polarizer is designed to validate the presented modeling procedure. Comparison with full-wave simulations confirms its high accuracy over a wide frequency range.
Autors: Roberto Vincenti Gatti;Riccardo Rossi;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 6179 - 6184
Publisher: IEEE
 
» A Novel Method for Low-Contrast and High-Noise Vessel Segmentation and Location in Venipuncture
Abstract:
Blood sampling is the most common medical technique, and vessel detection is of crucial interest for automated venipuncture systems. In this paper, we propose a new convex-regional-based gradient model that uses contextually related regional information, including vessel width size and gray distribution, to segment and locate vessels in a near-infrared image. A convex function with the interval size of vessel width is constructed and utilized for its edge-preserving superiority. Moreover, white and linear noise independences are derived. The region-based gradient decreases the number of local extreme in the cross-sectional profile of the vessel to realize its single global minimum in a low-contrast, noisy image. We demonstrate the performance of the proposed model via quantitative tests and comparisons between different methods. Results show the advantages of the model on the continuity and smoothness of segmented vessel. The proposed model is evaluated with receiver operating characteristic curves, which have a corresponding area under the curve of 88.8%. The proposed model will be a powerful method in automated venipuncture system and medical image analysis.
Autors: Yuhe Li;Zhendong Qiao;Shaoqin Zhang;Zhenhuan Wu;Xueqin Mao;Jiahua Kou;Hong Qi;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Nov 2017, volume: 36, issue:11, pages: 2216 - 2227
Publisher: IEEE
 
» A Novel PM-Free High-Speed Linear Machine With Amorphous Primary Core
Abstract:
This paper proposes a novel dc-excited flux-modulated linear machine with a new primary structure for utilizing amorphous core. Although amorphous core is regarded as a good candidate in highly efficient electric machines, and is being investigated for decades, it has not been widely used in electric machines yet. The key challenge is the difficulty in slotting. For the new structure, the difficulty in slotting is avoided. Furthermore, the proposed machine is economical and has a robust double salient structure without any permanent magnets, and both single-toothed field and armature windings are located together in the primary core. By regulating the field excitation, the machine can operate at a wide speed range. Due to the low loss of amorphous core, this machine shows high efficiency at high speed.
Autors: Jing Ou;Yingzhen Liu;Markus Schiefer;Martin Doppelbauer;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 8
Publisher: IEEE
 
» A Novel PNPN-Like Z-Shaped Tunnel Field- Effect Transistor With Improved Ambipolar Behavior and RF Performance
Abstract:
To suppress the ambipolar behavior and improve RF performance in tunnel field-effect transistors (TFETs), a Z-shaped (ZS)-TFET is proposed. The proposed ZS-TFET is more scalable than other vertical band-to-band-based TFETs and provides higher ON-state current (), larger ON/OFF current ratio () and lower subthreshold swing compared to conventional TFETs. These advantages stem from the tunneling junction in the ZS-TFET being perpendicular to the channel direction, which facilitates the formation of a relatively large tunneling junction area. The ZS body makes use of both vertical and horizontal fields while suppressing the lateral parasitic tunneling current. In addition, by using a ZS gate in the proposed device, the energy band diagram near the source is modulated to create an N+ source pocket which creates a downward band bending of the potential, similar to PNPN-like structures. Finally, the proposed structure significantly improves the analog/RF figure-of-merit.
Autors: Rouzbeh Molaei Imenabadi;Mehdi Saremi;William G. Vandenberghe;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Nov 2017, volume: 64, issue:11, pages: 4752 - 4758
Publisher: IEEE
 
» A Novel Sketch Attack for H.264/AVC Format-Compliant Encrypted Video
Abstract:
In this paper, we propose a novel sketch attack for H.264 advanced video coding (H.264/AVC) format-compliant encrypted video. We briefly describe the notion of sketch attack, review the conventional sketch attacks designed for discrete cosine transform (DCT)-based compressed image, and identify their shortcomings when applied to attack compressed video. Specifically, the conventional DCT-based sketch attacks are incapable in sketching outlines for inter frame, which is deployed to significantly reduce temporal redundancy in video compression. To sketch directly from inter frame, we put forward a sketch attack by considering the partially decoded information of the H.264/AVC compressed video, namely, the number of bits spent on coding a macroblock. To evaluate the sketch image, we consider the Canny edge map as the ideal outline image. Experiments are conducted to verify the performance of the proposed sketch attack using ICADR2013, High Efficiency Video Coding dash, and Xiph video data sets. Results suggest that the proposed sketch attack can generate the outline image of the original frame for not only intra frame but also inter frame.
Autors: Kazuki Minemura;KokSheik Wong;Raphael C.-W. Phan;Kiyoshi Tanaka;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Nov 2017, volume: 27, issue:11, pages: 2309 - 2321
Publisher: IEEE
 
» A Novel Structure Single-Phase Tubular Switched Reluctance Linear Motor
Abstract:
Tubular switched reluctance linear motor (TSRLM) has lower loss and higher thrust density than flat-type switched reluctance linear motor. Two kinds of single-phase TSRLMs with different surrounding magnetic flux paths are introduced in this paper. The structure of transverse flux TSRLM (TF-TSRLM) is compared with the structure of the longitudinal flux TSRLM (LF-TSRLM). The structure selection of TF-TSRLM with two poles, four poles, six poles, and eight poles is made for enhancing average electromagnetic thrust. The comparisons between LF-TSRLM and TF-TSRLM are made in the same stator outer diameter, the same mover laminated thickness, and the same excited current on static electromagnetic thrust, magnetization curves, average thrust per unit volume, and average thrust per unit mass. They show that the TF-TSRLM with the six-pole structure is considered as a relatively more reasonable structure for enhancing the space effective utilization rate and increasing the electromagnetic thrust.
Autors: Hao Chen;Rui Nie;Wenju Yan;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Novel Three-Phase Compact Saturated-Core Fault Current Limiter
Abstract:
The application of fault current limiter is an effective method to limit fault current. The saturated-core fault current limiter (SFCL) is one of the promising devices. However, its commercialization is limited by the high demands for the ferromagnetic material and the dc source generating magneto motive force. This paper proposes a novel three-phase compact SFCL (CSFCL) in which a common core and a permanent magnet are used to solve the mentioned challenges. The common core can significantly reduce the amount of required ferromagnetic material. The basic operating principle of CSFCL is introduced based on the analysis of the CSFCL’s magnetic circuit and equivalent electrical circuit. Finite-element analysis (FEA) simulations were performed by ANSOFT to validate the effectiveness of the CSFCL’s fault clipping performance.
Autors: Jiaxin Yuan;Yongheng Zhong;Shuhan Liao;Liangliang Wei;Yanhui Gao;Kazuhiro Muramatsu;Jiabin Jia;Baichao Chen;Liangjun Bai;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Novel Torque Quality Improvement of an Asymmetric Windings Permanent-Magnet Synchronous Motor
Abstract:
This paper introduces a new control approach to improve the output torque quality of a surface-mounted permanent-magnet synchronous motor with asymmetric windings. The impact of the asymmetry is reflected in the newly developed mathematical model of the motor based on dq0 voltages, flux linkages, and torque. Using this model, a control strategy based on vector control technique is proposed. This algorithm aims to eliminate the zero-sequence current, thereby improving the motor performance. The capability of the proposed algorithm has been demonstrated via simulation and experimental results.
Autors: E. Yolacan;M. K. Guven;M. Aydin;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» A Novel Ultra-Sensitive Nitrogen Dioxide Sensor Based on Germanium Monosulfide Monolayer
Abstract:
Nitrogen dioxide (NO2) is a representative toxic gas that plays a key role in variety of fields. Due to its extensive application, the demands for reliable sensors to detect NO2 are extremely urgent. Here, we report the adsorption of N2, CO2, O2, and NO2 molecules on the GeS monolayer from atomic scale to device scale by first principles and molecular dynamics method. The results indicate that the GeS monolayer is sensitive to NO2 molecules with moderate adsorption energy and pronounced charge transfer. Remarkably, the sorption quantity of the GeS monolayer for NO2 is 708.707 mg/g under the 101.33 kPa, which is much higher than other molecules. Additionally, the I–V characteristic reveals that when the NO2 molecule is adsorbed, the resistance of the GeS monolayer is nontrivially and distinctly changed. The extraordinary sensitivity and selectivity of the GeS monolayer for NO2 molecules suggests the GeS monolayer is a potential sensing material for NO2 gas.
Autors: Shao-Gang Wang;Chun-Jian Tan;Qun Yang;Yi-Xin Xu;Shao-Lin Li;Xian-Ping Chen;
Appeared in: IEEE Electron Device Letters
Publication date: Nov 2017, volume: 38, issue:11, pages: 1590 - 1593
Publisher: IEEE
 
» A Partitioned-Stator Flux-Switching Permanent-Magnet Machine With Mechanical Flux Adjusters for Hybrid Electric Vehicles
Abstract:
In this paper, three partitioned-stator (PS) machines, namely the PS flux-switching permanent-magnet (PS-FSPM) machine, the PS-FS hybrid-excitation machine, and the flux adjuster PS-FSPM (FA-PS-FSPM) machine are proposed for the hybrid electric vehicles (HEVs). Owing to the installation of additional inner-stators, all three proposed machines can offer satisfactory power and torque densities. In particular, the FA-PS-FSPM machine artfully utilizes its inner space to accommodate the mechanical FAs, such that outstanding flux-weakening capability for wide-speed range operation can be achieved. To verify the proposed concept, the established machines are purposely compared with the profound Prius HEV machine based on finite-element method.
Autors: Christopher H. T. Lee;James L. Kirtley;M. Angle;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 7
Publisher: IEEE
 
» A Passivity-Preserving Frequency-Weighted Model Order Reduction Technique
Abstract:
Frequency-weighted model order reduction techniques aim to yield a reduced order model whose output matches that of the original system in the emphasized frequency region. However, passivity of the original system is only known to be preserved in the single-sided weighted case. A frequency-weighted model order reduction technique is proposed, which guarantees the passive reduced models in the double-sided weighted case. A set of easily computable error bound expressions are also presented.
Autors: Umair Zulfiqar;Waseem Tariq;Li Li;Muwahida Liaquat;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Nov 2017, volume: 64, issue:11, pages: 1327 - 1331
Publisher: IEEE
 
» A Performance Prediction for Fe–Ga Magnetostrictive Strain Sensor Using Simplified Model
Abstract:
This paper presents an engineering modeling methodology for magnetostrictive materials based on a simplified piezo-electric governing equation. For verifying the modeling performance, a proof-of-concept non-contact strain sensor utilizing a prototype magnetostrictive (Fe–Ga alloy, Galfenol) strip on a steel plate is used to evaluate sensor performance prediction. Typically, the performance of Galfenol is measured in a compressional load region because it has a higher response. However, in this paper, we are aiming to develop a sensor for tensile stress measurement. To achieve a compression effect from a tension load in the sensing element, a Galfenol strip is aligned perpendicular to a tension bar so that tension in the bar creates compression in the strip via the Poisson effect. The experimental setup in this paper consists of a polycrystalline Galfenol strip bonded in the horizontal direction of a steel dog-bone shaped tension specimen. Permanent magnets are attached at each end of the Galfenol strip to provide an even magnetic bias field through the strip. The magnetic flux through the Galfenol strip is measured with non-contact Hall sensors during the tensile load test. The simulation results agree well with the experiments for the value of studied.
Autors: JinHyeong Yoo;Nicholas J. Jones;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Physical-Layer Security Scheme by Phase-Based Adaptive Modulation
Abstract:
Improving confidentiality is a main concern in most wireless transmission systems. Traditionally, confidentiality is guaranteed by means of encryption, where transmitted data are encrypted prior to transmission and only the intended receiver(s) can decrypt them. However, encryption/decryption process involves high complexity and heavy signaling in the key distribution/agreement protocols. Thus, aiming toward overcoming complexity, physical-layer security has been proposed as a promising candidate to improve confidentiality against eavesdroppers by exploiting physical-layer techniques. In this paper, we propose a physical-layer security scheme that adapts the modulation type based on the channel phase in order to secure the transmitted data. Moreover, the phase of the transmitted signal is adjusted in order to improve the immunity against eavesdroppers. The proposed scheme has been designed to achieve high robustness against channel estimation errors. The performance of the proposed scheme is evaluated through analysis and simulations in order to demonstrate the significant improvement in the confidentiality.
Autors: Saud Althunibat;Victor Sucasas;Jonathan Rodriguez;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Nov 2017, volume: 66, issue:11, pages: 9931 - 9942
Publisher: IEEE
 
» A Pipeline-Based Ray-Tracing Runtime System for HSA-Compliant Frameworks
Abstract:
Ray-tracing has received great attention over the years due to the high demand for global illumination appliances. Due to its embarrassingly parallel characteristics, the ray-tracing algorithm has been ported to the graphics processing unit (GPU) on heterogeneous systems that run thousands of threads in a single-instruction-multiple-thread fashion. However, the irregularity of ray-tracing causes a performance penalty on the GPU. The control flow divergence and early-termination problems severely degrade the hardware utilization, which makes the GPU computation inefficient while traversing through each iteration of the algorithm. Furthermore, additional overheads caused by data marshalling and load unbalancing negate the benefits of using heterogeneous systems. To tackle these issues, we designed a pipeline-based runtime methodology that leverages the features of heterogeneous system architecture (HSA)-compliant heterogeneous frameworks, such as shared virtual memory and fast kernel dispatching. This method merges the workloads from different iteration stages and dispatches them simultaneously. The merged workload is further assigned to a heterogeneous queue to enhance load balancing and scalability. With the proposed technologies, the performance of ray-tracing is enhanced significantly while effectively increasing the utilization of HSA-compliant heterogeneous systems. Based on the experiment results, the throughput becomes 4.37 times greater than the original setup on average in a single GPU mode and would always yield a greater throughput with a heterogeneous queue on multiple cores.
Autors: Chih-Chen Kao;Yu-Tsung Miao;Wei-Chung Hsu;
Appeared in: IEEE Transactions on Multimedia
Publication date: Nov 2017, volume: 19, issue:11, pages: 2450 - 2462
Publisher: IEEE
 
» A Pixel Pitch-Matched Ultrasound Receiver for 3-D Photoacoustic Imaging With Integrated Delta-Sigma Beamformer in 28-nm UTBB FD-SOI
Abstract:
This paper presents a pixel pitch-matched readout chip for 3-D photoacoustic (PA) imaging, featuring a dedicated signal conditioning and delta-sigma modulation integrated within a pixel area of 250 by 250 . The proof-of-concept receiver was implemented in an STMicroelectronics’s 28-nm Fully Depleted Silicon On Insulator technology, and interfaces to a subarray of capacitive micromachined ultrasound transducers (CMUTs). The front-end signal conditioning in each pixel employs a coarse/fine gain tuning architecture to fulfill the 90-dB dynamic range requirement of the application. The employed delta-sigma beamforming architecture obviates the need for area-consuming Nyquist ADCs and thereby enables an efficient in-pixel A/D conversion. The per-pixel switched-capacitor modulator leverages slewing-dominated and area-optimized inverter-based amplifiers. It occupies only 1/4th of the pixel, and its area compares favorably with state-of-the-art designs that offer the same SNR and bandwidth. The modulator’s measured peak signal-to-noise-and-distortion ratio is 59.9 dB for a 10-MHz input bandwidth, and it consumes 6.65 mW from a 1-V supply. The overall subarray beamforming approach improves the area per channel by 7.4 times and the single-channel SNR by 8 dB compared to prior art with similar delay resolution and power dissipation. The functionality of the designed chip was evaluated within a PA imaging experiment, employing a flip-chip bonded 2-D CMUT array.
Autors: Man-Chia Chen;Aldo Peña Perez;Sri-Rajasekhar Kothapalli;Philippe Cathelin;Andreia Cathelin;Sanjiv Sam Gambhir;Boris Murmann;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Nov 2017, volume: 52, issue:11, pages: 2843 - 2856
Publisher: IEEE
 
» A Planar Junctionless FET Using SiC With Reduced Impact of Interface Traps: Proposal and Analysis
Abstract:
In this paper, we propose the use of silicon carbide (SiC) material in a planar junctionless FET (JLFET) architecture for high-voltage operations. Using calibrated device simulations, we show that the planar SiC JLFET exhibits: 1) a breakdown voltage of ~60 V; 2) a subthreshold slope of 61 mV/decade; and 3) suppressed lateral band-to-band tunneling. In addition, the proposed device exhibits reduced impact of interface traps than the conventional SiC MOSFETs due to the bulk conduction and may not require additional fabrication steps such as counter-doping and annealing to neutralize the semiconductor-oxide traps. The device also gives excellent off-state characteristics and shows promising results as a future device for power MOS devices, system-on-panel, and 3-D-stacked applications.
Autors: Jaspreet Singh;Mamidala Jagadesh Kumar;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Nov 2017, volume: 64, issue:11, pages: 4430 - 4434
Publisher: IEEE
 
» A Planning and Guidance Platform for Cardiac Resynchronization Therapy
Abstract:
Patients with drug-refractory heart failure can greatly benefit from cardiac resynchronization therapy (CRT). A CRT device can resynchronize the contractions of the left ventricle (LV) leading to reduced mortality. Unfortunately, 30%–50% of patients do not respond to treatment when assessed by objective criteria such as cardiac remodeling. A significant contributing factor is the suboptimal placement of the LV lead. It has been shown that placing this lead away from scar and at the point of latest mechanical activation can improve response rates. This paper presents a comprehensive and highly automated system that uses scar and mechanical activation to plan and guide CRT procedures. Standard clinical preoperative magnetic resonance imaging is used to extract scar and mechanical activation information. The data are registered to a single 3-D coordinate system and visualized in novel 2-D and 3-D American Heart Association plots enabling the clinician to select target segments. During the procedure, the planning information is overlaid onto live fluoroscopic images to guide lead deployment. The proposed platform has been used during 14 CRT procedures and validated on synthetic, phantom, volunteer, and patient data.
Autors: Peter Mountney;Jonathan M. Behar;Daniel Toth;Maria Panayiotou;Sabrina Reiml;Marie-Pierre Jolly;Rashed Karim;Li Zhang;Alexander Brost;Christopher A. Rinaldi;Kawal Rhode;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Nov 2017, volume: 36, issue:11, pages: 2366 - 2375
Publisher: IEEE
 
» A Pole-to-Pole Short-Circuit Fault Current Calculation Method for DC Grids
Abstract:
This paper proposes a generic pole-to-pole short-circuit fault current calculation method for dc grids. The calculation procedure begins from the simplified RLC equivalent model of a single modular multilevel converter, and then the prefault matrices and faulted matrices are established and modified to calculate the dc fault currents of all the branches. The proposed approaches are validated by comparing with the electromagnetic transient (EMT) simulation results on PSCAD/EMTDC. Besides, two case studies showed that the calculation method can be easily used to evaluate the severity of a dc fault. Moreover, the calculation can be applied to select the parameters of a fault current limiter (to match the circuit breaker capacity. The main contributions of the proposed numerical calculation method are: 1) The proposed method is accurate and much more time efficient than the EMT simulations; 2) the proposed method can handle all kinds of dc grid networks including the ring, radial, and meshed topologies; and 3) the proposed method is applicable to dc grid with multiple dc voltage level areas connected with dc/dc converters.
Autors: Chengyu Li;Chengyong Zhao;Jianzhong Xu;Yuke Ji;Fan Zhang;Ting An;
Appeared in: IEEE Transactions on Power Systems
Publication date: Nov 2017, volume: 32, issue:6, pages: 4943 - 4953
Publisher: IEEE
 
» A Polymer-Based Air Gap Length Prediction Method With Current Injection and Fuzzy Logic Observer
Abstract:
In this paper, an approach combining current pulses injection and fuzzy logic observer to measure the air gap length of linear machines is proposed. A polymer enclosed by a coil is produced and selected as the test object. The characteristics and production process for the polymer is introduced and its magnetic feature has been studied. Injecting current pulses is used to calculate the self-inductance of the coil fixed on the cores that is directly influenced by the air gap length from the polymer. By using a fuzzy logic observer, the air gap length can be estimated precisely according to the variations of the self-inductance. Experimental results show the effectiveness of the proposed measurement method and the results prove that the proposed method is suitable for the air gap measurement for linear machines.
Autors: Yu Zou;K. W. Eric Cheng;Norbert C. Cheung;J. F. Pan;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» A Power Allocation Algorithm For Multi-Tier Cellular Networks With Heterogeneous QoS and Imperfect Channel Considerations
Abstract:
Interference management via resource allocation under the quality of service (QoS) provisions is a crucial challenge for next-generation cellular networks. The task becomes more problematic due to emerging services and applications with non-homogeneous QoS requirements. The resource allocation problem has mostly been investigated using ideal communication links, where it is generally assumed that information can be relayed perfectly between base stations (BSs). The impact of delays and time-outs at communication links during coordination of BSs is not well understood. Furthermore, it is generally assumed that perfect channel state information is available at BSs which may not always be possible due to large channel feedback delays or estimation errors. In this paper, we propose a power adjustment algorithm for heterogeneous networks which considers varying QoS requirements of users. Contrary to the power allocation approaches in the literature, channel state information is not required for power adjustment. The performance of the algorithm is evaluated both analytically and numerically under a setup with non-ideal communication links. The theoretical analysis unveils that the proposed algorithm achieves optimum power allocation with respect to the QoS requirements of users. The numerical results are not only in agreement with theoretical analysis, but also exhibits significant improvement in terms of overall network performance.
Autors: Kamil Senel;Mehmet Akar;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Nov 2017, volume: 16, issue:11, pages: 7184 - 7194
Publisher: IEEE
 
» A Practical Anisotropic Vector Hysteresis Model Based on Play Hysterons
Abstract:
An anisotropic vector hysteresis model based on the improved isotropic vector play operator has been presented to predict the magnetization behavior of anisotropic hysteresis materials. The required parameters can be identified from the major hysteresis loops in all principal axes, which can be easily measured, or are directly available from magnetic material manufacturers. The presented model, which has been successfully implemented in 2-D and 3-D transient finite-element analysis, is validated by numerical experiments and measured data cited from TEAM problem 32, and is applied to simulate a synchronous reluctance motor with an axially laminated anisotropic rotor.
Autors: D. Lin;P. Zhou;M. A. Rahman;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» A Precision Capacitance-to-Digital Converter With 16.7-bit ENOB and 7.5-ppm/°C Thermal Drift
Abstract:
This paper presents a high-precision capacitance-to-digital converter (CDC) for displacement measurement in advanced industrial applications, based on a charge-balancing third-order delta–sigma modulator. To achieve high precision, this CDC employs a precision external resistive reference and a quartz-oscillator-based time reference instead of a reference capacitor. To minimize the error contribution of the CDC circuitry, various precision circuit techniques, such as chopping and auto-zeroing, are applied at both system and circuit level. Measurement results of the prototype realized in 0.35- CMOS technology show that the CDC achieves an rms resolution of 42 aF across a capacitance range from 6 to 22 pF, corresponding to an effective number of bits (ENOB) of 16.7 bit. The conversion time for one measurement is 10.5 ms, during which the CDC consumes 230 from a 3.3-V single supply. The measured thermal stability is within ±7.5 ppm/°C across a temperature range from 20 °C to 70 °C, which represents a significant improvement compared to the state of the art. After a two-point calibration, all ten measured samples from one batch show absolute accuracy below ±25 fF across the entire capacitance measurement range.
Autors: Ruimin Yang;Michiel A. P. Pertijs;Stoyan Nihtianov;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Nov 2017, volume: 52, issue:11, pages: 3018 - 3031
Publisher: IEEE
 
» A Primer on Cluster Analysis: 4 Basic Methods That (Usually) Work [Book Review]
Abstract:
This book examine the concept of clustering. Clustering was important in the past, has become more important in the present era of internet, social networks, and big data, and will continue to remain so in future. We need clustering to find subgroups of cancers, clusters of stars in our galaxies, to answer web queries, to understand group dynamics in social networks—the list goes on. The book develops the necessary concepts such as similarity, distance, clusters, computer view point, human view point, and cluster validation in a very logical and lucid manner with plenty of easy-to-follow examples and creative pictures. Although the book primarily focuses on four types of popular clustering algorithms, it provides adequate materials and pointers for interested readers to sail through a much wider family of clustering algorithms. This book will be very useful (and of course enjoyable to read) to a wide spectrum of readers including beginners, researchers, and practitioners. It consists of 11 chapters divided into two parts: Part I: The Art and Science of Clustering, which has five chapters and Part II: Four Basic Models & Algorithms that contains the remaining six chapters.
Autors: Nikhil R. Pal;
Appeared in: IEEE Computational Intelligence Magazine
Publication date: Nov 2017, volume: 12, issue:4, pages: 98 - 100
Publisher: IEEE
 
» A Probabilistic Approach to People-Centric Photo Selection and Sequencing
Abstract:
We present a crowdsourcing (CS) study to examine how specific attributes probabilistically affect the selection and sequencing of images from personal photo collections. Thirteen image attributes are explored, including seven people-centric properties. We first propose a novel dataset shaping technique based on mixed integer linear programming (MILP) to identify a subset of photos in which the attributes of interest are uniformly distributed and minimally correlated. Shaping enables the synthesis of compact, balanced, and representative datasets for CS, and facilitates effective learning of the selection likelihood of an image as well as its relative position in a sequence, given its attributes. We further present an ILP-based slideshow creation framework to select and arrange (a subset of) appealing images from a personal photo library. Quantitative and qualitative evaluations confirm that our method outperforms regression-based and greedy approaches for photo selection and sequencing, generating slideshows similar in quality to those created by humans.
Autors: Vassilios Vonikakis;Ramanathan Subramanian;Jonas Arnfred;Stefan Winkler;
Appeared in: IEEE Transactions on Multimedia
Publication date: Nov 2017, volume: 19, issue:11, pages: 2609 - 2624
Publisher: IEEE
 
» A Probabilistic Framework for Protocol Conversions in IIoT Networks With Heterogeneous Gateways
Abstract:
Industrial Internet of Things (IIoT) supports multi-technology applications and data flow across IIoT networks incurs protocol conversion. Hence, an accurate estimation of network performance during data transmission must include the protocol conversion overhead. This overhead becomes significant in large IIoT networks, where data transmission relies on multi-hop transmission over specialized multi-technology gateways, which are heterogeneous in their technology support. This letter provides a probabilistic framework, which quantifies protocol conversions incurred by a packet while traversing through a heterogeneous gateway route. Results derived here can be used for forecasting the protocol conversion overhead, while designing network deployments supporting efficient traffic flows.
Autors: Revathy Narayanan;C. Siva Ram Murthy;
Appeared in: IEEE Communications Letters
Publication date: Nov 2017, volume: 21, issue:11, pages: 2456 - 2459
Publisher: IEEE
 
» A Probabilistic Model for the Nonlinear Electromagnetic Inverse Scattering: TM Case
Abstract:
Electromagnetic inverse scattering (EMIS) is a noninvasive examination tool, which holds the promising potential in science, engineering, and military applications. In contrast to conventional tomography techniques, the inverse scattering is a quantitative superresolution imaging method since it is capable of accommodating more realistic interactions between the wavefield and the probed scene. In this paper, a full probabilistic formulation of the EMIS is presented for the first time, which is then solved by applying the well-known expectation maximization method. Afterward, the concept of the complex-valued alternating direction method of multipliers has been proposed as an alternative approach to solve the resulting nonlinear optimization problem. Finally, exemplary numerical and experimental results are provided to validate the proposed method.
Autors: Lianlin Li;Long Gang Wang;Jun Ding;P. K. Liu;M. Y. Xia;Tie Jun Cui;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5984 - 5991
Publisher: IEEE
 
» A Real-Time Passenger Flow Estimation and Prediction Method for Urban Bus Transit Systems
Abstract:
Bus service is the most important function of public transportation. Besides the major goal of carrying passengers around, providing a comfortable travel experience for passengers is also a key business consideration. To provide a comfortable travel experience, effective bus scheduling is essential. Traditional approaches are based on fixed timetables. The wide adoptions of smart card fare collection systems and GPS tracing systems in public transportation provide new opportunities for using the data-driven approaches to fit the demand of passengers. In this paper, we associate these two independent data sets to derive the passengers’ origin and destination. As the data are real time, we build a system to forecast the passenger flow in real time. To the best of our knowledge, this is the first paper, which implements a system utilizing smart card data and GPS data to forecast the passenger flow in real time.
Autors: Jun Zhang;Dayong Shen;Lai Tu;Fan Zhang;Chengzhong Xu;Yi Wang;Chen Tian;Xiangyang Li;Benxiong Huang;Zhengxi Li;
Appeared in: IEEE Transactions on Intelligent Transportation Systems
Publication date: Nov 2017, volume: 18, issue:11, pages: 3168 - 3178
Publisher: IEEE
 
» A Reconfigurable Dual-Frequency Narrowband CMOS LNA Using Phase-Change RF Switches
Abstract:
This paper presents a dual-band low-noise amplifier (LNA) that can be reversibly configured between 3 and 5 GHz using a phase-change (PC) RF switch. Simultaneous noise and conjugate input matching is achieved at the two frequencies using a single PC RF switch and coupled source inductors, thereby minimizing integration complexity and enabling a compact design roughly equal in size to a single-band design. The PC switch has extremely low on-state resistance (1.5–) and parasitic capacitance (12–16 fF), and has a compact footprint (). A chip containing the PC switch is fabricated in-house while the rest of the LNA is fabricated in a 0.13- CMOS technology. The two chips are combined using an in-house flip-chip integration process. Characterization from five prototypes fabricated in two batches is presented. The integrated LNAs achieved peak gain greater than 20 dB and minimum noise figure less than 2.9 dB in both the frequency bands while consuming a peak power of 7.2 mW from a 1.2-V supply. Comparison of the CMOS-PC prototypes with carefully designed control LNAs demonstrates the effectiveness of the PC switch for RF reconfiguration, which allows the reconfigurable LNA to achieve performance comparable to its nonreconfigurable counterparts.
Autors: Rahul Singh;Gregory Slovin;Min Xu;T. E. Schlesinger;James A. Bain;Jeyanandh Paramesh;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Nov 2017, volume: 65, issue:11, pages: 4689 - 4702
Publisher: IEEE
 
» A Regression Method Based on Noninvasive Clinical Data to Predict the Mechanical Behavior of Ascending Aorta Aneurysmal Tissue
Abstract:
Goal: Ascending aorta aneurysms represent a severe life-threatening condition associated with asymptomatic risk of rupture. Prediction of aneurysm evolution and rupture is one of the hottest investigation topics in cardiovascular science, and the decision on when and whether to surgically operate is still an open question. We propose an approach for estimating the patient-specific ultimate mechanical properties and stress–stretch characteristics based on noninvasive data. Methods: As for the characteristics, we consider a nonlinear constitutive model of the aortic wall and assume patient-specific model coefficients. Through a regression model, we build the response surfaces of ultimate stress, ultimate stretch, and model coefficients in function of patient data that are commonly available in the clinical practice. We apply the approach to a dataset of 59 patients. Results: The approach is fair and accurate response surfaces can be obtained for both ultimate properties and model coefficients. Conclusion: Prediction errors are acceptable, even though a larger patient dataset will be required to stabilize the surfaces, making it possible to apply the approach in the clinical practice. Significance: A fair prediction of the patient aortic mechanical behavior, based on clinical information noninvasively acquired, would improve the decision process and lead to more effective treatments.
Autors: Ferdinando Auricchio;Anna Ferrara;Ettore Lanzarone;Simone Morganti;Pasquale Totaro;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Nov 2017, volume: 64, issue:11, pages: 2607 - 2617
Publisher: IEEE
 
» A Resistant Strain: Revealing the Online Grassroots Rise of the Antivaccination Movement
Abstract:
An analysis of more than eight years of data from vaccination forums on mothering.com shows that the antivaccination movement is well-organized and widely dispersed, and that it emerged long before concerns about immunity were expressed. The findings are evidence of a formidable challenge to the social norms surrounding vaccination.
Autors: Roja Bandari;Zicong Zhou;Hai Qian;Timothy R. Tangherlini;Vwani P. Roychowdhury;
Appeared in: Computer
Publication date: Nov 2017, volume: 50, issue:11, pages: 60 - 67
Publisher: IEEE
 
» A Resource Allocation Mechanism Using Matching and Bargaining
Abstract:
A resource allocation mechanism based on matching and bargaining is presented. There are many resource providers and many resource seekers. The resource valuations of the agents are private and are uniformly distributed over a common support. The regulator establishes two bid levels. Each participating agent is randomly paired with a counterpart and the allocations arise out of these bilateral encounters based on agents’ individual bid choices. We show a Bayes Nash equilibrium in dominant strategy when the regulator fixes the strategy for one set of agents. The mechanism has parameters to tune the allocations.
Autors: Swapan Sikdar;Sidney Givigi;Karen Rudie;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Nov 2017, volume: 62, issue:11, pages: 5909 - 5914
Publisher: IEEE
 
» A Rise-Dimensional Modeling and Estimation Method for Flight Trajectory Error in Bistatic Forward-Looking SAR
Abstract:
Bistatic forward-looking synthetic aperture radar (BFSAR) is a kind of bistatic SAR system that can image forward-looking terrain in the flight direction of a moving platform. In BFSAR, compensation of the flight trajectory errors is of great significance to get a well-focused image. To accomplish an accurate motion compensation in image processing, a high-precision navigation system is needed. However, in many cases, due to the accuracy limit of such systems, flight trajectory errors are hard to be compensated correctly, causing mainly the resolution decrease in final images. In order to cope with such a problem, we propose a rise-dimensional modeling and estimation for flight trajectory error based on raw BFSAR data in this paper. To apply this method, we first carry out a preprocessing named azimuth-slowtime decoupling to deal with the spatially variant flight trajectory error before estimation. Then, an optimization model for flight trajectory estimation under the criterion of maximum image intensity is built. The solution to the optimization model is the accurate flight trajectory. Then, block coordinate descent technique is used to solve this optimization model. The processing of BFSAR data shows that the algorithm can obtain a more accurate estimation results, and generate better focused images compared with the existing trajectory estimation method.
Autors: Wei Pu;Junjie Wu;Yulin Huang;Ke Du;Wenchao Li;Jianyu Yang;Haiguang Yang;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Nov 2017, volume: 10, issue:11, pages: 5001 - 5015
Publisher: IEEE
 
» A Robust Bisection-Based Estimator for TOA-Based Target Localization in NLOS Environments
Abstract:
This letter addresses the problem of target localization in harsh indoor environments based on range measurements. To mitigate the non-line-of-sight (NLOS) bias, we propose a novel robust estimator by transforming the localization problem into a generalized trust region sub-problem framework. Although still non-convex in general, this class of problems can be readily solved exactly by means of bisection procedure. The new approach does not require to make any assumptions about the statistics of NLOS bias, nor to try to distinguish which links are NLOS and which are not. Unlike the existing algorithms, the computational complexity of the proposed algorithm is linear in the number of reference nodes. Our simulation results corroborate the effectiveness of the new algorithm in terms of NLOS bias mitigation and show that the performance of our estimator is highly competitive with the performance of the state-of-the-art algorithms. In fact, they show that the novel estimator outperforms slightly the existing ones in general, and that it always provides a feasible solution.
Autors: Slavisa Tomic;Marko Beko;Rui Dinis;Paulo Montezuma;
Appeared in: IEEE Communications Letters
Publication date: Nov 2017, volume: 21, issue:11, pages: 2488 - 2491
Publisher: IEEE
 
» A Robust Yaw and Pitch Estimation Method for Mini-InSAR System
Abstract:
For the mini-interferometric synthetic aperture radar system mounted on small aircraft or unmanned aerial vehicles, yaw and pitch angle deviations can be considerably high due to their small size and atmospheric turbulence. Moreover, we cannot install a large-volume, heavy-weight, and high-cost inertial navigation system limited by the aircraft’s carrying capacity and system cost. In view of the problem, this letter proposes a robust yaw and pitch angle estimation method based on the relationship between range-variant Doppler centroid and attitude angles. For each azimuth moment, estimate the range-variant Doppler centroid for each range gate and solve the range-variant Doppler centroid model using a total least squares method to obtain a robust yaw and pitch angle estimation result. The comparison of the estimated and recorded yaw and pitch angles by a high-accuracy position and orientation system validated the effectiveness and reliability of our proposed yaw and pitch angle estimation method.
Autors: Xikai Fu;Maosheng Xiang;Bingnan Wang;Shuai Jiang;Xiaofan Sun;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Nov 2017, volume: 14, issue:11, pages: 2157 - 2161
Publisher: IEEE
 
» A Saliency Prior Context Model for Real-Time Object Tracking
Abstract:
Real-time object tracking has wide applications in time-critical multimedia processing areas such as motion analysis and human–computer interaction. It remains a hard problem to balance between accuracy and speed. In this paper, we present a fast real-time context-based visual tracking algorithm with a new saliency prior context (SPC) model. Based on the probability formulation, the tracking problem is solved by sequentially maximizing the computed confidence map of target location in each video frame. To handle the various cases of feature distributions generated from different targets and their contexts, we exploit low-level features as well as fast spectral analysis for saliency to build a new prior context model. Then, based on this model and a spatial context model learned online, a confidence map is computed and the target location is estimated. In addition, under this framework, the tracking procedure can be accelerated by the fast Fourier transform. Therefore, the new method generally achieves a real-time running speed. Extensive experiments show that our tracking algorithm based on the proposed SPC model achieves real-time computation efficiency with overall best performance comparing with other state-of-the-art methods.
Autors: Cong Ma;Zhenjiang Miao;Xiao-Ping Zhang;Min Li;
Appeared in: IEEE Transactions on Multimedia
Publication date: Nov 2017, volume: 19, issue:11, pages: 2415 - 2424
Publisher: IEEE
 
» A Screening Rule-Based Iterative Numerical Method for Observability Analysis
Abstract:
Observability analysis determines whether a unique system state estimate can be obtained for a given set of measurements, i.e., if the system is fully observable. It is an essential requirement for robust power system state estimation and may be carried out offline to determine whether a measurement configuration is adequate, or online to ensure that any changes in the available measurements (e.g., communication or meter failures) have not created isolated observable islands. One aspect of observability analysis is identifying the observable islands, i.e., the subnetworks within the power system in which the states can still be uniquely estimated with the measurements available. The existing numerical methods for observability analysis are noniterative, but fail to correctly identify the observable islands in certain cases. In this paper, the flaw in the underlying theorems behind these existing methods has been identified and a new iterative method is presented that overcomes it. However, online observability analysis is time sensitive, so iterative methods are undesirable. Therefore, a pathological case identification rule (PCIR) is proposed that allows the iterative procedure to be terminated early, if iterations are no longer necessary to prevent an incorrect identification. Furthermore, the new PCIR allows direct identification of observable islands, which allows the proposed iterative method to be faster than the existing noniterative methods. The proposed iterative method and the PCIR are based on mathematical proofs and explained with numerical examples, while the speed improvement from direct island identification is demonstrated using simulations of the IEEE 14 and 2736 bus test systems.
Autors: Zhaoyang Jin;Papiya Dattaray;Peter Wall;James Yu;Vladimir Terzija;
Appeared in: IEEE Transactions on Power Systems
Publication date: Nov 2017, volume: 32, issue:6, pages: 4188 - 4198
Publisher: IEEE
 
» A Secure Approach for Caching Contents in Wireless Ad Hoc Networks
Abstract:
Caching aims to store data locally in some nodes within the network to be able to retrieve the contents in shorter time periods. However, caching in the network did not always consider secure storage (due to the compromise between time performance and security). In this paper, a novel decentralized secure coded caching approach is proposed. In this solution, nodes only transmit coded files to avoid eavesdropper wiretappings and protect the user contents. In this technique random vectors are used to combine the contents using XOR operation. We modeled the proposed coded caching scheme by a Shannon cipher system to show that coded caching achieves asymptotic perfect secrecy. The proposed coded caching scheme significantly simplifies the routing protocol in cached networks while it reduces overcaching and achieves a higher throughput capacity compared to uncoded caching in reactive routing. It is shown that with the proposed coded caching scheme any content can be retrieved by selecting a random path while achieving asymptotic optimum solution. We have also studied the cache hit probability and shown that the coded cache hit probability is significantly higher than uncoded caching. A secure caching update algorithm is also presented.
Autors: Mohsen Karimzadeh Kiskani;Hamid R. Sadjadpour;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Nov 2017, volume: 66, issue:11, pages: 10249 - 10258
Publisher: IEEE
 
» A Semantic Web Approach to Simplifying Trigger-Action Programming in the IoT
Abstract:
End-user programming environments for the IoT such as IFTTT rely on a multitude of low-level trigger-action rules that categorize devices and services by technology or brand. EUPont is a Semantic Web ontology that enables users to meet their needs with fewer, higher-level rules that can be adapted to different contextual situations and as-yet-unknown IoT devices and services.
Autors: Fulvio Corno;Luigi De Russis;Alberto Monge Roffarello;
Appeared in: Computer
Publication date: Nov 2017, volume: 50, issue:11, pages: 18 - 24
Publisher: IEEE
 
» A Sharpening of the Welch Bounds and the Existence of Real and Complex Spherical $t$ –Designs
Abstract:
The Welch bounds for a finite set of unit vectors are a family of inequalities indexed by , which describe how “evenly spread” the vectors are. They have important applications in signal analysis, where sequences giving equality in the first Welch bound are known as Welch bound equality sequences or as unit norm tight frames. Here, we consider sequences of vectors giving equality in the higher order Welch bounds. These are seen to correspond to tight frames for the complex symmetric –tensors (which we prove always exist). We show that for , the Welch bounds can be sharpened for real vectors, and again, vectors giving equality always exist. We give a unified treatment of various conditions for equality in both the real and complex cases. In particular, we give an explicit description of the corresponding cubature rules (–designs). Our results set up a framework for the construction and classification several configurations of vectors of recent interest. These include mutually unbiased bases, complex equiangular lines, spherical half–designs, projective –designs, and minimisers of the higher order frame potential. One interesting consequence is a construction of sets of complex equiangular lines, which were previously unknown.
Autors: Shayne Waldron;
Appeared in: IEEE Transactions on Information Theory
Publication date: Nov 2017, volume: 63, issue:11, pages: 6849 - 6857
Publisher: IEEE
 
» A Si-Compatible Fabrication Process for Scaled Self-Aligned InGaAs FinFETs
Abstract:
We have developed a scalable gate-last process to fabricate self-aligned InGaAs FinFETs that relies on extensive use of dry etch. The process involves F-based dry etching of refractory metal ohmic contacts that are formed early in the process. The fins are etched in a novel inductive coupled plasma process using BCl3/SiCl4/Ar. High aspect ratio fins with smooth sidewalls are obtained. To further improve the quality of the sidewalls and shrink the fin width, digital etch is used. Through this process flow, we have demonstrated FinFETs with nm and fin width as narrow as 7 nm with high yield. Good electrostatic characteristics are obtained in a wide range of device dimensions. In devices with 7 nm fin width, record channel aspect ratio, and transconductance per unit footprint are obtained.
Autors: A. Vardi;J. Lin;W. Lu;X. Zhao;A. Fernando-Saavedra;J. A. del Alamo;
Appeared in: IEEE Transactions on Semiconductor Manufacturing
Publication date: Nov 2017, volume: 30, issue:4, pages: 468 - 474
Publisher: IEEE
 

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