Electrical and Electronics Engineering publications abstract of: 09-2017 sorted by title, page: 9

» Forest Change Detection in Incomplete Satellite Images With Deep Neural Networks
Abstract:
Land cover change monitoring is an important task from the perspective of regional resource monitoring, disaster management, land development, and environmental planning. In this paper, we analyze imagery data from remote sensing satellites to detect forest cover changes over a period of 29 years (1987–2015). Since the original data are severely incomplete and contaminated with artifacts, we first devise a spatiotemporal inpainting mechanism to recover the missing surface reflectance information. The spatial filling process makes use of the available data of the nearby temporal instances followed by a sparse encoding-based reconstruction. We formulate the change detection task as a region classification problem. We build a multiresolution profile (MRP) of the target area and generate a candidate set of bounding-box proposals that enclose potential change regions. In contrast to existing methods that use handcrafted features, we automatically learn region representations using a deep neural network in a data-driven fashion. Based on these highly discriminative representations, we determine forest changes and predict their onset and offset timings by labeling the candidate set of proposals. Our approach achieves the state-of-the-art average patch classification rate of 91.6% (an improvement of ~16%) and the mean onset/offset prediction error of 4.9 months (an error reduction of five months) compared with a strong baseline. We also qualitatively analyze the detected changes in the unlabeled image regions, which demonstrate that the proposed forest change detection approach is scalable to new regions.
Autors: Salman H. Khan;Xuming He;Fatih Porikli;Mohammed Bennamoun;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Sep 2017, volume: 55, issue:9, pages: 5407 - 5423
Publisher: IEEE
 
» Forward and Backward Extended Prony (FBEP) Method for Power System Small-Signal Stability Analysis
Abstract:
The performance of the Forward and Backward Extended Prony (FBEP) method on power system small-signal stability analysis is investigated in this paper. The effectiveness of the FBEP method in identifying system eigenvalues from the output signal is validated by experiments on a test system model. Using a four-machine-two-area power system model the estimation of the dominant modes contained in oscillatory signals given by the FBEP method is compared with that given by the SVD-TLS method, Trudnowski's algorithm, and the Prony with stepwise regression method. The multi-signal analysis and sliding window analysis using the FBEP method are also studied.
Autors: Shuang Zhao;Kenneth A. Loparo;
Appeared in: IEEE Transactions on Power Systems
Publication date: Sep 2017, volume: 32, issue:5, pages: 3618 - 3626
Publisher: IEEE
 
» Foundations of a Bicoprime Factorization Theory
Abstract:
Bicoprime factorizations (BCFs) are a generalization of the well known coprime factorizations commonly used in control theory. However they have received negligible attention from the academic community so far. This technical note lays the foundations of a BCF theory. The theory is built from the ground up, starting with the basic characteristics of such factorizations before moving on to state space parameterizations of BCFs and internal stability. Some advantages of BCFs are outlined including the possibility of reduced dimension internal stability tests. An uncertainty structure induced by BCFs is also examined and the associated robust stability analysis tests provided. In multiple instances it is shown how coprime factor results have their roots in the more abstract, and more general, BCFs.
Autors: Mihalis Tsiakkas;Alexander Lanzon;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Sep 2017, volume: 62, issue:9, pages: 4598 - 4603
Publisher: IEEE
 
» Frequency Reconfigurable Multiband Handset Antenna Based on a Multichannel Transceiver
Abstract:
The upcoming standards of wireless communications result in additional and more stringent requirements for antennas in mobile phones. In this paper, we present a frequency-reconfigurable antenna that could potentially be suited for future mobile devices. Frequency reconfigurability is achieved through a cluster of mutually coupled antenna elements that is excited with frequency-dependent weights using a multichannel transceiver. We report a mobile handset antenna cluster measuring 15 15 1.6 mm3 that covers the frequency bands of 1.7–2.7, 3.3–4.5, and 5.475–6.425 GHz with an antenna efficiency better than 90%. The operation of the antenna cluster is experimentally verified by feeding all the antenna elements with proper weights using tailor-made power splitters that represent a multichannel transceiver with adjustable amplitude and phase in each branch. The results obtained with the feed networks suggest the feasibility of the reconfigurability concept and pave way for codesign of the antenna and the transceiver.
Autors: Jari-Matti Hannula;Tapio Saarinen;Jari Holopainen;Ville Viikari;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Sep 2017, volume: 65, issue:9, pages: 4452 - 4460
Publisher: IEEE
 
» From the editors' desk
Abstract:
Presents the introductory editorial for this issue of the publication.
Autors: Ed Cherney;Robert Fleming;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Sep 2017, volume: 33, issue:5, pages: 7 - 8
Publisher: IEEE
 
» Full 2-D Submillimeter-Wave Frequency Scanning Array
Abstract:
A 2-D frequency scanning array operating in the 220–320-GHz frequency band is presented. The array is composed of 64 open-ended rectangular waveguides arranged in an configuration. The feeding circuit comprises two waveguide-based phase shifting networks, which provides the required phase shift between adjacent radiating elements when the working frequency is modified. The array was manufactured over brass sheets through a mechanical procedure and experimentally characterized, providing beam steering along a space region while the working frequency is swept between 220 and 320 GHz, with a maximum −10-dB secondary lobe level and a measured 17-dBi gain at 275 GHz.
Autors: René Camblor;Samuel Ver Hoeye;Miguel Fernández;Carlos Vázquez Antuña;Fernando Las-Heras;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Sep 2017, volume: 65, issue:9, pages: 4486 - 4494
Publisher: IEEE
 
» Full-Duplex Amplify-and-Forward Relaying: Power and Location Optimization
Abstract:
In this paper, we consider a full-duplex (FD) amplify-and-forward relay system and optimize its power allocation and relay location to minimize the system symbol error rate (SER). We first derive the asymptotic expressions of the outage probability and SER performance by taking into account the residual self interference (RSI) in FD systems. We then formulate the optimization problem based on the minimal SER criterion. Analytical and numerical results show that optimized relay location and power allocation can greatly improve system SER performance, and the performance floor caused by the RSI can be significantly reduced via optimizing relay location or power allocation.
Autors: Shuai Li;Kun Yang;Mingxin Zhou;Jianjun Wu;Lingyang Song;Yonghui Li;Hongbin Li;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Sep 2017, volume: 66, issue:9, pages: 8458 - 8468
Publisher: IEEE
 
» Fully Coupled Multiphysics Simulation of Crosstalk Effect in Bipolar Resistive Random Access Memory
Abstract:
A versatile multiphysics simulation packet for investigating different resistive random acces memories (RRAMs) is developed in this paper. Heat transfer, electrical conduction, and ion migration in such heterogeneous structure are all taken into consideration. Three fully coupled partial differential equations are solved using our self-developed finite-difference algorithm, where Scharfetter–Gummel method is adopted to simulate ion migration with fast convergence achieved. This packet is validated in comparison with the commercial software based on the finite-element method. With its implementation, complete and clear pictures for crosstalk effect in vertically integrated RRAM are captured and compared, where the effects of key physical and geometrical factors are characterized and understood. Some useful suggestions to mitigate its unfavorable influences are given.
Autors: Shichao Li;Wenchao Chen;Yandong Luo;Jun Hu;Pingqi Gao;Jichun Ye;Kai Kang;Hongsheng Chen;Erping Li;Wen-Yan Yin;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Sep 2017, volume: 64, issue:9, pages: 3647 - 3653
Publisher: IEEE
 
» Fully Integrated Fluorescence Biosensors On-Chip Employing Multi-Functional Nanoplasmonic Optical Structures in CMOS
Abstract:
Integrated optical system-on-chip in silicon operating in the visible range can have a tremendous impact on enabling new applications in sensing and imaging through the ultra-miniaturization of complex optical instrumentation. CMOS technology has allowed an integration of optical detection circuitry for image sensors with massively large number of pixels. In this paper, we focus on techniques to realize complex optical-field processing elements inside CMOS by exploiting optical interaction with sub-wavelength metal nanostructures realized in the electrical interconnects layers, whose feature sizes are now in the sub-100-nm range. In particular, we present a fully integrated fluorescence-based bio-molecular sensor in 65-nm CMOS with integrated nanoplasmonic waveguide-based filters capable of more than 50 dB of rejection ratio across a wide range of incident angles. Co-designed with the integrated photo-detection circuitry, capacitive TIAs, and correlated double-sampling circuitry, the sensor is capable of detecting 48 zeptomoles of quantum dots on the surface with 52 fA of photodetector current with a fluorescence/excitation ratio of nearly −62 dB without any post-fabrication, external optical filters, lenses, or collimators. The ability to integrate complex nanoplasmonic metal structures with unique optical properties in CMOS with no post-processing creates the opportunity to enable large multiplexed assays on a single chip and a wide variety of applications, from in vitro to in vivo.
Autors: Lingyu Hong;Hao Li;Haw Yang;Kaushik Sengupta;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Sep 2017, volume: 52, issue:9, pages: 2388 - 2406
Publisher: IEEE
 
» Fusion of Deep Convolutional Neural Networks for Land Cover Classification of High-Resolution Imagery
Abstract:
Deep convolutional neural networks (DCNNs) have recently emerged as the highest performing approach for a number of image classification applications, including automated land cover classification of high-resolution remote-sensing imagery. In this letter, we investigate a variety of fusion techniques to blend multiple DCNN land cover classifiers into a single aggregate classifier. While feature-level fusion is widely used with deep neural networks, our approach instead focuses on fusion at the classification/information level. Herein, we train three different DCNNs: CaffeNet, GoogLeNet, and ResNet50. The effectiveness of various information fusion methods, including voting, weighted averages, and fuzzy integrals, is then evaluated. In particular, we used DCNN cross-validation results for the input densities of fuzzy integrals followed by evolutionary optimization. This novel approach produces the state-of-the-art classification results up to 99.3% for the UC Merced data set and the 99.2% for the RSD data set.
Autors: Grant J. Scott;Richard A. Marcum;Curt H. Davis;Tyler W. Nivin;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Sep 2017, volume: 14, issue:9, pages: 1638 - 1642
Publisher: IEEE
 
» Fuzzy Logic Based Adaptive Droop Control in Multiterminal HVDC for Wind Power Integration
Abstract:
Following a converter outage in a Multiterminal dc (MTDC) for offshore wind farm integration, the conventional droop control shares the power mismatch to minimize the impact on the wind power generation with a fixed droop coefficient; however, it may easily lead to the converter overloading and large dc voltage deviation. The paper proposes a fuzzy logic based adaptive droop controller, which utilizes the available power capacity of the converters to update the droop coefficient. It can make a compromise between the dc voltage deviation and the power sharing. Furthermore, the impact of the droop coefficient change on the stability of the MTDC grid is analyzed, and the effect of the dc-bus capacitor on the system dynamic is identified. The stability region is determined through the eigenvalue analysis. Time-domain simulations are conducted to compare the control strategy proposed with the conventional one. It has been proved that the adaptive control scheme can constantly track dynamic behaviors of the converters, and exhibit desirable response under different outage scenarios.
Autors: Xia Chen;Long Wang;Haishun Sun;Yin Chen;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Sep 2017, volume: 32, issue:3, pages: 1200 - 1208
Publisher: IEEE
 
» GALLOP: GlobAL Feature Fused LOcation Prediction for Different Check-in Scenarios
Abstract:
Location prediction is widely used to forecast users’ next place to visit based on his/her mobility logs. It is an essential problem in location data processing, invaluable for surveillance, business, and personal applications. It is very challenging due to the sparsity issues of check-in data. An often ignored problem in recent studies is the variety across different check-in scenarios, which is becoming more urgent due to the increasing availability of more location check-in applications. In this paper, we propose a new feature fusion based prediction approach, GALLOP, i.e., GlobAL feature fused LOcation Prediction for different check-in scenarios. Based on the carefully designed feature extraction methods, we utilize a novel combined prediction framework. Specifically, we set out to utilize the density estimation model to profile geographical features, i.e., context information, the factorization method to extract collaborative information, and a graph structure to extract location transition patterns of users’ temporal check-in sequence, i.e., content information. An empirical study on three different check-in datasets demonstrates impressive robustness and improvement of the proposed approach.
Autors: Yuxing Han;Junjie Yao;Xuemin Lin;Liping Wang;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Sep 2017, volume: 29, issue:9, pages: 1874 - 1887
Publisher: IEEE
 
» Game Factors Influencing Players to Continue Playing Online Pets
Abstract:
Online pet games emphasize the enjoyment of raising a pet, social interaction, and expression of the personality. Players often obtain a sense of satisfaction and develop companionship with their pets. However, the question pertinent to why people continue playing with online pets is still unclear. The answer of this question can help developers improve game designs. The flow experience is a factor contributing to players’ willingness to engage in a gaming activity. Therefore, the purpose of this study is to adopt the concept of flow to help understand why people enjoy playing online pet games. In this study, the authors analyzed flow factors and identified crucial game elements that might elicit a flow experience by means of a questionnaire survey. A total of 180 valid questionnaires were collected, and the results demonstrated that role playing is an important flow factor for online pet games. In addition, social interaction, personality design, and creativity behavior are crucial game elements contributing to players’ willingness to continue playing with online pets.
Autors: Ding-Bang Luh;Elena Carolina Li;Chia-Chen Dai;
Appeared in: IEEE Transactions on Computational Intelligence and AI in Games
Publication date: Sep 2017, volume: 9, issue:3, pages: 267 - 276
Publisher: IEEE
 
» Gamesman Problems [Gamesman Problems]
Abstract:
Autors: Athanasios Kakarountas;
Appeared in: IEEE Potentials
Publication date: Sep 2017, volume: 36, issue:5, pages: 48 - 48
Publisher: IEEE
 
» Gamesman Solutions [Gamesman Solutions]
Abstract:
Autors: Athanasios Kakarountas;
Appeared in: IEEE Potentials
Publication date: Sep 2017, volume: 36, issue:5, pages: 5 - 5
Publisher: IEEE
 
» Gate Leakage Mechanisms in AlInN/GaN and AlGaN/GaN MIS-HEMTs and Its Modeling
Abstract:
Gate leakage mechanisms in AlInN/GaN and AlGaN/GaN metal insulator semiconductor high-electron-mobility transistors (MIS-HEMTs) with SiNx as gate dielectric have been investigated. It is found that the conduction in the reverse gate bias is due to Poole-Frenkel emission for both MIS-HEMTs. The dominant conduction mechanism in low to medium forward bias is trap-assisted tunneling while it is Fowler–Nordheim tunneling at high forward bias. However, conduction near zero gate bias is dominated by defect-assisted tunneling for both sets of MIS-HEMTs. The gate leakage current is primarily dependent on the properties of the gate dielectric material and dielectric/ semiconductor interface rather than the barrier layer. A model is proposed for the gate leakage current in GaN-based MIS-HEMTs, and the method to extract the related model parameters is also presented in this paper. The proposed gate current model matches well with the experimental results for both AlInN/GaN and AlGaN/GaN MIS-HEMTs over a wide range of gate bias and measurement temperature.
Autors: Gourab Dutta;Nandita DasGupta;Amitava DasGupta;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Sep 2017, volume: 64, issue:9, pages: 3609 - 3615
Publisher: IEEE
 
» Gaussian Pyramid: Comparative Analysis of Hardware Architectures
Abstract:
This paper addresses a comparison of architectures for the hardware implementation of Gaussian image pyramids. Main differences between architectural choices are in the sensor front-end. One side is for architectures consisting of a conventional sensor that delivers digital images and which is followed by digital processors. The other side is for architectures employing a non-conventional sensor with per-pixel embedded preprocessing structures for Gaussian spatial filtering. This later choice belongs to the general category of “artificial retina” sensors which have been for long claimed as potentially advantageous for enhancing throughput and reducing energy consumption of vision systems. These advantages are very important in the internet of things context, where imaging systems are constantly exchanging information. This paper attempts to quantify these potential advantages within a design space in which the degrees of freedom are the number and type of ADCs, single-slope, SAR, cyclic, , and pipeline, and the number of digital processors. Results show that speed and energy advantages of preprocessing sensors are not granted by default and are only realized through proper architectural design. The methodology presented for the comparison between focal-plane and digital approaches is a useful tool for imager design, allowing for the assessment of focal-plane processing advantages.
Autors: Fernanda D. V. R. Oliveira;José Gabriel R. C. Gomes;Jorge Fernández-Berni;Ricardo Carmona-Galán;Rocío del Río;Ángel Rodríguez-Vázquez;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Sep 2017, volume: 64, issue:9, pages: 2308 - 2321
Publisher: IEEE
 
» Gene-Sequencing-Based Indoor Localization in Distributed Antenna System
Abstract:
In the indoor distributed antenna system (DAS), base station transmits signals with even power via the distributed antennas. Thus, single reference signal received power (RSRP) from the receiver will result in accurate localization. In response to this compelling problem, we utilize the pedestrian dead reckoning, which is based on consecutive signals in collected RSRP sequences as the template sequences, to achieve high-performance location estimation. Specifically, the main idea of the proposed localization algorithm is calculating the correlation between the on-site sequence and each pre-constructed template sequence, which is labeled with human movement coordinates. Then, the prediction location is considered as the template sequence label that is with the largest approximation to the on-site sequence. Experiments are conducted with real time division long-term evolution signals in indoor DAS, and the corresponding experimental results demonstrate that the proposed approach can not only solve the problem of positioning in DAS, but also provide satisfactory localization accuracy.
Autors: Chengke Liu;Zengshan Tian;Mu Zhou;Xiaolong Yang;
Appeared in: IEEE Sensors Journal
Publication date: Sep 2017, volume: 17, issue:18, pages: 6019 - 6028
Publisher: IEEE
 
» General Power Equation of Switched Reluctance Machines and Power Density Comparison
Abstract:
Switched reluctance machines (SRMs) are becoming increasingly attractive due to their inherent advantages, such as robust and rare-earth-permanent magnet-free topology, as well as excellent fault-tolerance and temperature management. However, the accurate and efficient analyses of SRMs are always challenging since they operate with variable reluctance and pulsating excitation, suffering severe nonlinear characteristics. This paper first introduces a general power equation of SRMs, which can be a powerful tool in the investigation of SRMs. Then, the proposed power equation is validated by finite element (FE) results and experimental results with different excitations. Afterwards, the calculated results with various conditions including different stator inner diameters and different stator outer diameters are compared with the FE-predicted results. Finally, the comparison between SRMs and several conventional machines is carried out to evaluate the power density of SRMs.
Autors: Wei Hua;Guishu Zhao;Hao Hua;Ming Cheng;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Sep 2017, volume: 53, issue:5, pages: 4298 - 4307
Publisher: IEEE
 
» Generalized DTC Strategy for Multilevel Inverter Fed IPMSMs With Constant Inverter Switching Frequency and Reduced Torque Ripples
Abstract:
This paper proposes a generalized direct torque control (DTC) strategy for multilevel inverter fed DTC (MLI-DTC) drives. By using a simple voltage vector decomposition technique, the proposed method is compatible with inverters possessing any number of voltage levels. Consequently, voltage vectors are applied in a similar way as in the case of a two-level inverter fed DTC. A constant inverter switching frequency is imposed in the proposed method by using a torque regulator in place of the traditional torque hysteresis controller, which enables the application of two voltage vectors within one switching cycle. This also contributes to reduce the torque and flux ripples. Detailed design guidelines for the proposed torque regulator are provided. Experimental results obtained with a three-level neutral point clamped inverter show that the proposed MLI-DTC drive operates with low, constant switching frequency while alleviating torque and flux ripples under all operating conditions. Comparative study with a prior art and parametric sensitivity analysis are also presented to verify the effectiveness and robustness of the proposed MLI-DTC method.
Autors: Deepu Mohan;Xinan Zhang;Gilbert Hock Beng Foo;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Sep 2017, volume: 32, issue:3, pages: 1031 - 1041
Publisher: IEEE
 
» Generalized MGF of Beckmann Fading With Applications to Wireless Communications Performance Analysis
Abstract:
The Beckmann distribution is a general multipath fading model for the received radio signal in the presence of a large number of scatterers, which can thence be modeled as a complex Gaussian random variable where both the in-phase and quadrature components have arbitrary mean and variance. However, the complicated nature of this distribution has prevented its widespread use and relatively few analytical results have been reported for this otherwise useful fading model. In this paper, we derive a closed-form expression for the generalized moment-generating function (MGF) of the signal-to-noise ratio (SNR) of Beckmann fading, which permits to circumvent the inherent analytical complexity of this model. This is a new and useful result, as it is a key for evaluating several important performance metrics of different wireless communication systems and also permits to readily compute the moments of the output SNR. Thus, we obtain simple exact expressions for the energy detection performance in Beckmann fading channels, both in terms of the receiver operating characteristic (ROC) curve and of the area under ROC curve. We also analyze the outage probability in interference limited systems affected by Beckmann fading, as well as the outage probability of secrecy capacity in wiretap Beckmann fading channels. Monte Carlo simulations have been performed to validate the derived expressions.
Autors: Juan P. Peña-Martín;Juan M. Romero-Jerez;F. Javier Lopez-Martinez;
Appeared in: IEEE Transactions on Communications
Publication date: Sep 2017, volume: 65, issue:9, pages: 3933 - 3943
Publisher: IEEE
 
» Generalized Pyramid Codes for Versioned Data in Distributed Storage Networks
Abstract:
A distributed storage framework called sparsity exploiting coding (SEC) was recently proposed for storing multiple versions of data object, wherein the objects are stored in a differential manner in order to reduce the I/O reads when retrieving multiple versions. It was shown that the design of erasure codes for the SEC framework requires Cauchy-matrix-based maximum distance separable (MDS) codes, which, however, do not enjoy the locally repairable property during the repair process. In this letter, we study the suitability of generalized pyramid codes (GPCs), a well-known class of locally repairable codes, to the SEC framework, and analyze their capability to retrieve multiple versions with few I/O reads. We show that GPCs can retrieve correlated multiple versions with fewer I/O reads than the overall object size, however, requiring more I/O reads than that by Cauchy-matrix-based MDS codes. This penalty in the I/O reads comes at the advantage of availing the locally repairable property in the SEC framework. We also show that GPCs require fewer I/O reads than the optimal locally repairable codes, in some cases.
Autors: J. Harshan;
Appeared in: IEEE Communications Letters
Publication date: Sep 2017, volume: 21, issue:9, pages: 1921 - 1924
Publisher: IEEE
 
» Generalized Shift-Map Codes and Their Decoding Using an Iterative Algorithm
Abstract:
This letter investigates an iterative algorithm for decoding analog error-correcting codes. First, the shift-map code, one of the widely studied analog codes, is generalized to yield a new family of codes with a more flexible tradeoff between errors at low and high signal-to-noise ratios. Then, an iterative decoding algorithm for the generalized shift-map codes is derived from a message-passing process on a sparse factor graph. Numerical simulations demonstrate that the proposed algorithm decodes generalized shift-map codes following a small number of iterations. Combined with the efficient decoding algorithm, the flexibility of the generalized shift-map codes will enhance the applicability of analog error-correcting codes.
Autors: Yongseok Yoo;
Appeared in: IEEE Communications Letters
Publication date: Sep 2017, volume: 21, issue:9, pages: 1909 - 1912
Publisher: IEEE
 
» Generation of 22.7-fs 2.8-nJ Pulses From an Erbium-Doped All-Fiber Laser Via Single-Stage Soliton Compression
Abstract:
We have demonstrated experimentally that few-cycle pulses can be achieved from an Er-doped fiber laser via single-stage soliton compression. Adopting negative prechirp amplification is to avoid the high-energy pulse break-up and increase the spectral width. Through optimizing the fiber length and pulse energy in different parts of the fiber laser system, the generated pulse can be as short as 22.7 fs, which is about four cycle duration at 1550 nm. The average power is up to 120 mW with the corresponding pulse energy of 2.8 nJ. Numerical simulation has been carried out to illustrate the dynamic of pulse prechirp, amplification, and compression.
Autors: Hao Luo;Li Zhan;Liang Zhang;Zhiqiang Wang;Caixia Gao;Xiao Fang;
Appeared in: Journal of Lightwave Technology
Publication date: Sep 2017, volume: 35, issue:17, pages: 3780 - 3784
Publisher: IEEE
 
» Generic Dynamic Models for Modeling Wind Power Plants and Other Renewable Technologies in Large-Scale Power System Studies
Abstract:
With the tremendous growth of wind power worldwide in the past decade, there has been an equally great demand for simplified, standard, and publicly available models for simulating wind power generators in commercially available power system simulation tools for stability analysis. Several efforts have been on the way to meet this need. The Western Electricity Coordinating Council's Renewable Energy Modeling Task Force has successfully achieved this goal and more recently has been working on expanding these models to include the ability to model complex plants, energy storage, and frequency response capabilities. This paper presents an account of these latest developments.
Autors: Pouyan Pourbeik;Juan J. Sanchez-Gasca;Jayapalan Senthil;James D. Weber;Pouya Sajjad Zadehkhost;Yuriy Kazachkov;Spencer Tacke;Jun Wen;Abraham Ellis;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Sep 2017, volume: 32, issue:3, pages: 1108 - 1116
Publisher: IEEE
 
» Genetic Algorithm-Based Current Optimization for Torque Ripple Reduction of Interior PMSMs
Abstract:
This paper investigates the torque ripple modeling and minimization for interior permanent magnet synchronous machines (PMSMs). At first, a novel torque ripple model is proposed in which the torque ripples resulted from the spatial harmonics of permanent magnet flux linkage, time harmonics of stator currents and the cogging torque are included. Based on the torque ripple model, a genetic algorithm (GA)-based harmonic current optimization approach is proposed for torque ripple minimization. In this approach, GA is applied to optimize both the magnitude and phase angle of the stator harmonic currents to minimize the peak-to-peak torque ripple, minimize the sum of squares of the harmonic currents, and maximize the average torque component produced by the injected harmonic currents. The results demonstrate that the magnitude of the harmonic current can be significantly reduced by optimizing the phase angles of these harmonic currents. This leads to further suppression of the torque ripple when compared with that of a case where phase angles are not considered in the optimization. Also, an increase of the average torque is achieved when the optimum harmonic currents are injected. The proposed model and approach are evaluated through both numerical and experimental investigations on a laboratory interior PMSM.
Autors: Chunyan Lai;Guodong Feng;K. Lakshmi Varaha Iyer;Kaushik Mukherjee;Narayan C. Kar;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Sep 2017, volume: 53, issue:5, pages: 4493 - 4503
Publisher: IEEE
 
» Geometry Analysis and Optimization of PM-Assisted Reluctance Motors
Abstract:
This paper deals with a detailed geometry analysis of the rotor structure for both synchronous reluctance and permanent magnet (PM)-assisted reluctance motor in order to suggest an automatic procedure to design the rotor structure. The shape of flux barriers is selected to achieve both high -axis inductance and low -axis inductance to obtain high output torque and high power factor. Methods to properly design the geometry of the ends of each barrier and PMs are adopted. In order to draw a rotor with proper shape, different modifications are discussed. All details are described to allow any reader to adopt the same procedures. After that, such a procedure is used to rapidly analyze the impact of some geometry changes on the machine performance to give a design guideline. The analyzing process starts from a reluctance motor considering the number of barriers, insulation ratio, split ratio, and slots per pole per phase. Then, the PMs are inset into flux barriers and the effect of PM width on torque, power factor, and flux weakening capability is investigated. At last, the demagnetization limit under overload operations is analyzed.
Autors: Yawei Wang;Giacomo Bacco;Nicola Bianchi;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Sep 2017, volume: 53, issue:5, pages: 4338 - 4347
Publisher: IEEE
 
» Geometry of Line Start Synchronous Motors Suitable for Various Pole Combinations
Abstract:
Line start synchronous motors (LSSM) have been recently introduced in the motor market to meet new efficiency class requirements. They exhibit high efficiency and power factor compared with induction motors. On the other hand, the difficult design, manufacture, and high cost due to the presence of permanent magnets limit their widespread use in the market. Another key factor that limits the LSSM diffusion is the need of having a wide variety of different laminations of different sizes, increasing the number of pieces to be stored, the number of mold geometries, etc. This paper investigates the opportunity to use a proper geometry of LSSM that allows the same stator and rotor laminations to be used for a different number of poles. From the manufacturing point of view, the adoption of a unique rotor lamination is extremely advantageous. It is shown that satisfactory performance can be achieved rearranging the stator winding according to the number of poles. Experimental measurements are carried out on an LSSM prototype in which the same lamination is used for 2-pole and 4-pole machines.
Autors: Damiano Mingardi;Nicola Bianchi;Michele Dai Prè;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Sep 2017, volume: 53, issue:5, pages: 4360 - 4367
Publisher: IEEE
 
» GfcLLL: A Greedy Selection-Based Approach for Fixed-Complexity LLL Reduction
Abstract:
The LLL lattice reduction has been widely used to decrease the bit error rate (BER) of the Babai point, but its running time varies much from matrix to matrix. To address this problem, some fixed-complexity LLL reductions (FCLLL) have been proposed. In this letter, we propose two greedy selection-based FCLLL algorithms: GfcLLL(1) and GfcLLL(2). Simulations show that both of them give Babai points with lower BER in similar or much shorter CPU time than existing ones.
Autors: Jinming Wen;Xiao-Wen Chang;
Appeared in: IEEE Communications Letters
Publication date: Sep 2017, volume: 21, issue:9, pages: 1965 - 1968
Publisher: IEEE
 
» Global Chartwise Feedback Linearization of the Quadcopter With a Thrust Positivity Preserving Dynamic Extension
Abstract:
We propose a new dynamic extension of the thrust variable in the quadcopter dynamics that preserves the positive sign of the thrust. This extension not only eliminates the positive sign constraint on the thrust variable, but also leads to global chartwise feedback linearization of the quadcopter dynamics. For the latter, an atlas is first constructed on the entire state space of the quadcopter and then the dynamically extended quadcopter system is transformed to a 14-dimensional linear controllable system on each chart in the atlas. Based on the chartwise dynamic feedback linearization, a global tracking strategy is proposed for the quadcopter and its excellent performance is demonstrated with a simulation.
Autors: Dong Eui Chang;Yongsoon Eun;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Sep 2017, volume: 62, issue:9, pages: 4747 - 4752
Publisher: IEEE
 
» Glucose Monitoring in Individuals With Diabetes Using a Long-Term Implanted Sensor/Telemetry System and Model
Abstract:
Objective: The use of a fully implanted first-generation prototype sensor/telemetry system is described for long-term monitoring of subcutaneous tissue glucose in a small cohort of people with diabetes. Methods: Sensors are based on a membrane containing immobilized glucose oxidase and catalase coupled to oxygen electrodes and a telemetry system, integrated as an implant. The devices remained implanted for up to 180 days, with signals transmitted every 2 min to external receivers. Results: The data include signal recordings from glucose clamps and spontaneous glucose excursions, matched, respectively, to reference blood glucose and finger-stick values. The sensor signals indicate dynamic tissue glucose, for which there is no independent standard, and a model describing the relationship between blood glucose and the signal is, therefore, included. The values of all model parameters have been estimated, including the permeability of adjacent tissues to glucose, and equated to conventional mass transfer parameters. As a group, the sensor calibration varied randomly at an average rate of −2.6%/week. Statistical correlation indicated strong association between the sensor signals and reference glucose values. Conclusion: Continuous long-term glucose monitoring in individuals with diabetes is feasible with this system. Significance: All therapies for diabetes are based on glucose control, and therefore, require glucose monitoring. This fully implanted long-term sensor/telemetry system may facilitate a new era of management of the disease.
Autors: Joseph Y. Lucisano;Timothy L. Routh;Joe T. Lin;David A. Gough;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Sep 2017, volume: 64, issue:9, pages: 1982 - 1993
Publisher: IEEE
 
» Go ?Get Chipped?: A Brief Overview of Non-Medical Implants between 1997-2013 (Part 1)
Abstract:
Autors: Katina Michael;
Appeared in: IEEE Technology and Society Magazine
Publication date: Sep 2017, volume: 36, issue:3, pages: 6 - 9
Publisher: IEEE
 
» GOFP: A Geometric-Optical Model for Forest Plantations
Abstract:
Geometric-optical (GO) model suitable for forest plantation (GOFP) is a GO model for forest plantations at the stand level developed in this study based on a four-scale GO model a Geometric-Optical Model for Sloping Terrains-II (GOST2), which simulates the bidirectional reflectance distribution function (BRDF) for natural forest canopies. In most previous GO models, tree distributions are often assumed to meet the Poisson or Neyman model in a forest; therefore, these models are suitable for simulating BRDF for natural forest canopies. However, in forest plantations, tree distributions are proven to meet the hypergeometric model rather than the Poisson or Neyman model at the stand level. GOFP, in which the tree distributions are described using the hypergeometric model, is proposed to simulate the bidirectional reflectance factor (BRF) of forest plantations at the stand level. The area ratios of the four scene components (sunlit foliage, sunlit ground, shaded foliage, and shaded ground) of GOFP compare well with those simulated by a 3-D canopy visualization technique. A comparison is also made against discrete anisotropic radiative transfer, showing that GOFP has the ability to simulate BRF of forest plantations. Another comparison is made against operational land imager and Moderate Resolution Imaging Spectroradiometer surface reflectance, showing that GOFP with the hypergeometric model outperforms GOST2 with the Poisson and Neyman models. The results further show that the differences in BRFs between GOFP and GOST2 pronouncedly increase with the difference between the reflectance of sunlit foliage () and the reflectance of sunlit ground (), as well as the distances among trees and the number of crowns in a forest plantation, suggesting that GOFP significantly outperforms GOST2 for simulating BRF - f forest plantations.
Autors: Jun Geng;Jing M. Chen;Weiliang Fan;Lili Tu;Qingjiu Tian;Ranran Yang;Yanjun Yang;Lei Wang;Chunguang Lv;Shengbiao Wu;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Sep 2017, volume: 55, issue:9, pages: 5230 - 5241
Publisher: IEEE
 
» Going Cooler With Timing-Constrained TeSHoP: A Temperature Sensing-Based Hotspot-Driven Placement Technique for FPGAs
Abstract:
The continuous shrinking of the feature size in CMOS technology has significantly increased the power densities of integrated circuits, leading to severe temperature issues. However, the previous offline simulation-based thermal optimization works cast large deviations with the reality, while online sensing-based thermal managements usually incur significant performance overhead. Therefore, it is crucial to propose a method that could achieve fine-grained optimization with accurate temperature profiles. In this paper, we propose a timing-constraint temperature sensing-based hotspot-driven placement technique for field-programmable gate arrays (FPGAs). The hotspot optimization issue is modeled as a hyper minimum bipartite matching problem and is solved by a place adjustment with the input of an online sensed temperature profile. We propose an open-source/commercial hybrid design flow to implement the whole optimization in Xilinx Virtex-6 FPGA. Experimental results demonstrate a significant reduction in peak temperature and a great improvement on thermal uniformity, with slight performance overhead under timing constraints.
Autors: Weina Lu;Yu Hu;Jing Ye;Xiaowei Li;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Sep 2017, volume: 25, issue:9, pages: 2525 - 2537
Publisher: IEEE
 
» GPS-Disciplined Analog-to-Digital Converter for Phasor Measurement Applications
Abstract:
This paper presents a data acquisition unit which synchronously samples multiple channels in a manner such that the time of day at which each sample is taken is known. This allows measurements taken at multiple locations to be compared with confidence. The intended application is wide area electrical power system measurements, in particular phasor measurement units (PMUs). The novelty of the authors’ design is the application of an open hardware development platform to discipline a commodity analog-to-digital converter (ADC) to a broadcast time signal, usually but not exclusively GPS. The methodology used creates a driver layer for the ADC to achieve real-time sampling in a nonpreemptive Linux environment. The use of open hardware and software addresses the need for a transparent instrument for use in research and development of PMU technology. Through a choice of either a software or hardware phase-locked loop, the ADC is controlled to acquire exactly 256 samples per nominal power system cycle (i.e., 50/60 Hz), precisely time synchronized to GPS, at 16-b resolution and 94.2-dB SNR. The design of a printed circuit board expansion board featuring all necessary components is provided. The performance of the system is evaluated. Interoperability and data exchange with other systems is achieved by use of open schemas and communication protocols. This allows rapid integration with popular numerical simulation environments.
Autors: Xiaodong Zhao;David M. Laverty;Adrian McKernan;D. John Morrow;Kieran McLaughlin;Sakir Sezer;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Sep 2017, volume: 66, issue:9, pages: 2349 - 2357
Publisher: IEEE
 
» GPU Parallel Implementation of Isometric Mapping for Hyperspectral Classification
Abstract:
Manifold learning algorithms such as the isometric mapping (ISOMAP) algorithm have been widely used in the analysis of hyperspectral images (HSIs), for both visualization and dimension reduction. As advanced versions of the traditional linear projection techniques, the manifold learning algorithms find the low-dimensional feature representation by nonlinear mapping, which can better preserve the local structure of the original data and thus benefit the data analysis. However, the high computational complexity of the manifold learning algorithms hinders their application in HSI processing. Although there are a few parallel implementations of manifold learning approaches that are available in the remote sensing community, they have not been designed to accelerate the eigen-decomposition process, which is actually the most time-consuming part of the manifold learning algorithms. In this letter, as a case study, we discuss the graphics processing unit parallel implementation of the ISOMAP algorithm. In particular, we focus on the eigen-decomposition process and verify the applicability of the proposed method by validating the embedding vectors and the subsequent classification accuracies. The experimental results obtained on different HSI data sets show an excellent speedup performance and consistent classification accuracy compared with the serial implementation.
Autors: Wan Li;Liangpei Zhang;Lefei Zhang;Bo Du;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Sep 2017, volume: 14, issue:9, pages: 1532 - 1536
Publisher: IEEE
 
» Graph Codes for Distributed Instant Message Collection in an Arbitrary Noisy Broadcast Network
Abstract:
We consider the problem of minimizing the number of broadcasts for collecting all sensor measurements at a sink node in a noisy broadcast sensor network. Focusing first on arbitrary network topologies, we provide: 1) fundamental limits on the required number of broadcasts of data gathering and 2) a general in-network computing strategy to achieve an upper bound within factor of the fundamental limits, where is the number of agents in the network. Next, focusing on two example networks, namely, arbitrary geometric networks and random Erdös-Rényi networks, we provide improved in-network computing schemes that are optimal in that they attain the fundamental limits, i.e., the lower and upper bounds are tight in scaling sense. Our main techniques are three distributed encoding techniques, called graph codes, which are designed, respectively, for the above-mentioned three scenarios. Our work, thus, extends and unifies previous works such as those of Gallager and Karamchandani on the number of broadcasts for distributed function computation in special network topologies, while bringing in novel techniques, e.g., from error-control coding and noisy circuits, for both upper and lower bounds.
Autors: Yaoqing Yang;Soummya Kar;Pulkit Grover;
Appeared in: IEEE Transactions on Information Theory
Publication date: Sep 2017, volume: 63, issue:9, pages: 6059 - 6084
Publisher: IEEE
 
» Graph Filters and the Z-Laplacian
Abstract:
In network science, the interplay between dynamical processes and the underlying topologies of complex systems has led to a diverse family of models with different interpretations. In graph signal processing, this is manifested in the form of different graph shifts and their induced algebraic systems. In this paper, we propose the unifying Z-Laplacian framework, whose instances can act as graph shift operators. As a generalization of the traditional graph Laplacian, the Z-Laplacian spans the space of all possible Z -matrices, i.e., real square matrices with nonpositive off-diagonal entries. We show that the Z -Laplacian can model general continuous-time dynamical processes, including information flows and epidemic spreading on a given graph. It is also closely related to general nonnegative graph filters in the discrete time domain. We showcase its flexibility by considering two applications. First, we consider a wireless communications networking problem modeled with a graph, where the framework can be applied to model the effects of the underlying communications protocol and traffic. Second, we examine a structural brain network from the perspective of low- to high-frequency connectivity.
Autors: Xiaoran Yan;Brian M. Sadler;Robert J. Drost;Paul L. Yu;Kristina Lerman;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Sep 2017, volume: 11, issue:6, pages: 774 - 784
Publisher: IEEE
 
» Graph Learning From Data Under Laplacian and Structural Constraints
Abstract:
Graphs are fundamental mathematical structures used in various fields to represent data, signals, and processes. In this paper, we propose a novel framework for learning/estimating graphs from data. The proposed framework includes (i) formulation of various graph learning problems, (ii) their probabilistic interpretations, and (iii) associated algorithms. Specifically, graph learning problems are posed as the estimation of graph Laplacian matrices from some observed data under given structural constraints (e.g., graph connectivity and sparsity level). From a probabilistic perspective, the problems of interest correspond to maximum a posteriori parameter estimation of Gaussian–Markov random field models, whose precision (inverse covariance) is a graph Laplacian matrix. For the proposed graph learning problems, specialized algorithms are developed by incorporating the graph Laplacian and structural constraints. The experimental results demonstrate that the proposed algorithms outperform the current state-of-the-art methods in terms of accuracy and computational efficiency.
Autors: Hilmi E. Egilmez;Eduardo Pavez;Antonio Ortega;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Sep 2017, volume: 11, issue:6, pages: 825 - 841
Publisher: IEEE
 
» Graph PCA Hashing for Similarity Search
Abstract:
This paper proposes a new hashing framework to conduct similarity search via the following steps: first, employing linear clustering methods to obtain a set of representative data points and a set of landmarks of the big dataset; second, using the landmarks to generate a probability representation for each data point. The proposed probability representation method is further proved to preserve the neighborhood of each data point. Third, PCA is integrated with manifold learning to lean the hash functions using the probability representations of all representative data points. As a consequence, the proposed hashing method achieves efficient similarity search (with linear time complexity) and effective hashing performance and high generalization ability (simultaneously preserving two kinds of complementary similarity structures, i.e., local structures via manifold learning and global structures via PCA). Experimental results on four public datasets clearly demonstrate the advantages of our proposed method in terms of similarity search, compared to the state-of-the-art hashing methods.
Autors: Xiaofeng Zhu;Xuelong Li;Shichao Zhang;Zongben Xu;Litao Yu;Can Wang;
Appeared in: IEEE Transactions on Multimedia
Publication date: Sep 2017, volume: 19, issue:9, pages: 2033 - 2044
Publisher: IEEE
 
» Graph Signal Recovery via Primal-Dual Algorithms for Total Variation Minimization
Abstract:
We consider the problem of recovering a smooth graph signal from noisy samples taken on a subset of graph nodes. The smoothness of the graph signal is quantified in terms of total variation. We formulate the signal recovery task as a convex optimization problem that minimizes the total variation of the graph signal while controlling its global or node-wise empirical error. We propose a first-order primal-dual algorithm to solve these total variation minimization problems. A distributed implementation of the algorithm is devised to handle large-dimensional applications efficiently. We use synthetic and real-world data to extensively compare the performance of our approach with state-of-the-art methods.
Autors: Peter Berger;Gabor Hannak;Gerald Matz;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Sep 2017, volume: 11, issue:6, pages: 842 - 855
Publisher: IEEE
 
» Grasping Objects: The Relationship Between the Cage and the Form-Closure Grasp
Abstract:
In various industries, there is a need for low-cost, flexible robotic grasping systems that handle and classify different items, which usually involve low-cost grippers and reliable manipulations. One-degree-offreedom (1-DoF) two-pin or three-pin grippers are widely used in the automation of manufacturing processes because of their low cost and high reliability. However, some uncertainties introduced by the object and the gripper may affect the robustness of the grasp. The principle of caging enables us to deal with these uncertainties, and it is therefore important to study caging as a practical solution to improve the grasps of 1-DoF industrial grippers.
Autors: Jianhua Su;Hong Qiao;Chuankai Liu;Yongbo Song;Ailong Yang;
Appeared in: IEEE Robotics & Automation Magazine
Publication date: Sep 2017, volume: 24, issue:3, pages: 84 - 96
Publisher: IEEE
 
» Grid-Level Application of Electrical Energy Storage: Example Use Cases in the United States and China
Abstract:
Electrical energy storage (EES) systems are expected to play an increasing role in helping the United States and China-the world's largest economies with the two largest power systems-meet the challenges of integrating more variable renewable resources and enhancing the reliability of power systems by improving the operating capabilities of the electric grid. EES systems are becoming integral components of a resilient and efficient grid through a diverse set of applications that include energy management, load shifting, frequency regulation, grid stabilization, and voltage support.
Autors: Yingchen Zhang;Vahan Gevorgian;Caixia Wang;Xuejiao Lei;Ella Chou;Rui Yang;Qionghui Li;Liping Jiang;
Appeared in: IEEE Power and Energy Magazine
Publication date: Sep 2017, volume: 15, issue:5, pages: 51 - 58
Publisher: IEEE
 
» Ground Moving Target Imaging and Motion Parameter Estimation With Airborne Dual-Channel CSSAR
Abstract:
This paper deals with the issue of ground moving target imaging and motion parameter estimation with an airborne dual-channel circular stripmap synthetic aperture radar (CSSAR) system. Although several methods of ground moving target motion parameter estimation have been proposed for the conventional airborne linear stripmap SAR, they cannot be applied to airborne CSSAR because the range history of a ground moving target for airborne CSSAR is different than that for airborne linear stripmap SAR. In this paper, the moving target’s range history for airborne dual-channel CSSAR and the target signal model after the displaced phase center antenna processing are derived, and a new ground moving target imaging and motion parameter estimation algorithm is developed. In this algorithm, the estimation of baseband Doppler centroid and its compensation are first performed. Then focusing is implemented in the 2-D frequency domain via phase multiplication, and the target is focused in the SAR image without azimuth displacement due to the compensation of the Doppler shift caused by its motion. Finally, the target’s motion parameters are estimated with its Doppler parameters and its position in the SAR image. Numerical simulations are conducted to validate the derived range history and the performance of the proposed algorithm.
Autors: Yongkang Li;Tong Wang;Baochang Liu;Lei Yang;Guoan Bi;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Sep 2017, volume: 55, issue:9, pages: 5242 - 5253
Publisher: IEEE
 
» Guest Editorial
Abstract:
This Mini-Special Issue of the IEEE Transactions on Microwave Theory and Techniques includes six expanded papers from the first IEEE MTT-S Latin American Microwave Conference (LAMC 2016), which was held in Puerto Vallarta, Jalisco, México, December 12–14, 2016.
Autors: Roberto S. Murphy;Vicente E. Boria-Esbert;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Sep 2017, volume: 65, issue:9, pages: 3085 - 3086
Publisher: IEEE
 
» Guest Editorial Modeling and Advanced Control of Wind Turbines/Wind Farms
Abstract:
The papers in this special section brings together papers focused on the recent advancements and breakthroughs in the technology of modeling and enhanced active/reactive power control of wind power conversion systems, ranging from components of wind turbines to wind farms.
Autors: J. Hu;Y. Hou;Z. Zhu;D. Xu;D. Xu;E. Muljadi;F. Liu;G. Iwanski;H. Geng;I. Erlich;J. Wen;L. Harnefors;L. Fan;M. S. El Moursi;P. C. Kjaer;R. J. Nelson;R. Cárdenas;S. Feng;S. Islam;W. Qiao;X. Yuan;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Sep 2017, volume: 32, issue:3, pages: 1105 - 1107
Publisher: IEEE
 
» Guest Editorial Special Issue on Circuits and Systems for the Internet of Things—From Sensing to Sensemaking
Abstract:
The Internet of Things (IoT) refers to the interconnection of everyday objects endowed with sensing, processing, communication and energy management capabilities [item 1) in the Appendix] (the “IoT nodes”). Being at the beginning of its “S curve” in terms of stage of adoption [item 2) in the Appendix] (see “innovators” in Fig. 1), the IoT promises to be the next big wave that will further raise the technological and economic impact of the semiconductor industry. More than a decade from now, the massive adoption of IoT technologies (see “late majority” in Fig. 1) is expected to expand the number of connected devices per person to the order of a thousand, thus reaching an unprecedented scale of trillions of connected devices [item 3) in the Appendix].
Autors: Massimo Alioto;Edgar Sánchez-Sinencio;Alberto Sangiovanni-Vincentelli;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Sep 2017, volume: 64, issue:9, pages: 2221 - 2225
Publisher: IEEE
 
» Guest Editorial The Global Change Observation Mission—Water: Contributions to Global Water Cycle Science From the Advanced Microwave Scanning Radiometer–2
Abstract:
Autors: G. Heygster;M. Kachi;R. Kelly;G. Liu;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Sep 2017, volume: 10, issue:9, pages: 3835 - 3838
Publisher: IEEE
 
» Guest Editorial: Large-Scale Multimedia Data Retrieval, Classification, and Understanding
Abstract:
The papers in this special section focus on multimedia data retrieval and classification via large-scale systems. Today, large collections of multimedia data are explosively created in different fields and have attracted increasing interest in the multimedia research area. Large-scale multimedia data provide great unprecedented opportunities to address many challenging research problems, e.g., enabling generic visual classification to bridge the well-known semantic gap by exploring large-scale data, offering a promising possibility for in-depth multimedia understanding, as well as discerning patterns and making better decisions by analyzing the large pool of data. Therefore, the techniques for large-scale multimedia retrieval, classification, and understanding are highly desired. Simultaneously, the explosion of multimedia data puts urgent needs for more sophisticated and robust models and algorithms to retrieve, classify, and understand these data. Another interesting challenge is, how can the traditional machine learning algorithms be scaled up to millions and even billions of items with thousands of dimensionalities? This motivated the community to design parallel and distributed machine learning platforms, exploiting GPUs as well as developing practical algorithms. Besides, it is also important to exploit the commonalities and differences between different tasks, e.g., image retrieval and classification have much in common while different indexing methods evolve in a mutually supporting way.
Autors: J. Song;H. Jegou;C. Snoek;Q. Tian;N. Sebe;
Appeared in: IEEE Transactions on Multimedia
Publication date: Sep 2017, volume: 19, issue:9, pages: 1965 - 1967
Publisher: IEEE
 
» Guest Editorial: Special Section on the Seventh IEEE International Workshop on Applied Measurements for Power Systems (AMPS 2016) Aachen, Germany, September 28–30, 2016
Abstract:
The IEEE International Workshop on Applied Measurements for Power Systems (AMPS) is the main event promoted by TC-39 of the Instrumentation and Measurement Society (Measurements in Power Systems). It was held in Aachen, Germany, from September 28 to 30, 2016, and in its seventh edition was hosted again by the E.ON Energy Research Center, RWTH Aachen University. In the recent years, the workshop has continuously shown increasing numbers. It was, once more, a fruitful scientific meeting involving attendees from both industry and academia.
Autors: Carlo Muscas;Paolo Attilio Pegoraro;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Sep 2017, volume: 66, issue:9, pages: 2214 - 2215
Publisher: IEEE
 
» Guided-Processing Outperforms Duty-Cycling for Energy-Efficient Systems
Abstract:
Energy efficiency is highly desirable for sensing systems in the Internet of Things. A common approach to achieve low-power systems is duty cycling, where components in a system are turned OFF periodically to meet an energy budget. However, this paper shows that such an approach is not necessarily optimal in energy efficiency, and proposes guided processing as a fundamentally better alternative. The proposed approach offers: 1) explicit modeling of performance uncertainties in system internals; 2) a realistic resource consumption model; and 3) a key insight into the superiority of guided processing over duty cycling. Generalization from the cascade structure to the more general graph-based one is also presented. Once applied to optimize a large-scale audio sensing system with a practical detection application, empirical results show that the proposed approach significantly improves the detection performance (up to 1.7 times and 4 times reduction in false alarm and miss rate, respectively) for the same energy consumption, when compared with the duty-cycling approach.
Autors: Long N. Le;Douglas L. Jones;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Sep 2017, volume: 64, issue:9, pages: 2414 - 2426
Publisher: IEEE
 
» Hardware Trojan Detection Game: A Prospect-Theoretic Approach
Abstract:
Outsourcing integrated circuit (IC) manufacturing to offshore foundries has grown exponentially in recent years. Given the critical role of ICs in the control and operation of vehicular systems and other modern engineering designs, such offshore outsourcing has led to serious security threats due to the potential of insertion of hardware trojans—malicious designs that, when activated, can lead to highly detrimental consequences. In this paper, a novel game-theoretic framework is proposed to analyze the interactions between a hardware manufacturer, acting as an attacker, and an IC testing facility, acting as a defender. The problem is formulated as a noncooperative game in which the attacker must decide on the type of trojan that it inserts while taking into account the detection penalty as well as the damage caused by the trojan. Meanwhile, the resource-constrained defender must decide on the best testing strategy that allows optimizing its overall utility which accounts for both damages and the fines. The proposed game is based on the robust behavioral framework of prospect theory (PT) which allows capturing the potential uncertainty, risk, and irrational behavior in the decision making of both the attacker and defender. For both the standard rational expected utility (EUT) case and the PT case, a novel algorithm based on fictitious play is proposed and shown to converge to a mixed-strategy Nash equilibrium. For an illustrative case study, thorough analytical results are derived for both EUT and PT to study the properties of the reached equilibrium as well as the impact of key system parameters such as the defender-set fine. Simulation results assess the performance of the proposed framework under both EUT and PT and show that the use of PT will provide invaluable insights on the outcomes of the proposed hardware trojan game, in particular, and system security, in general.
Autors: Walid Saad;Anibal Sanjab;Yunpeng Wang;Charles A. Kamhoua;Kevin A. Kwiat;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Sep 2017, volume: 66, issue:9, pages: 7697 - 7710
Publisher: IEEE
 
» Hardware/Software Co-Design and VLSI Implementation for the Intelligent Surveillance System
Abstract:
In this paper, we present a hardware design for the intelligent surveillance system. We have developed a complete system-level solution on algorithm level, and then algorithm has been implemented in very-large-scale integration (VLSI). The behavior of the moving objects is evaluated using adaptive search method. We propose the method to track the moving people in successive frames by object boundary box and velocity without color cues or appearance model. Even though people are interacting with each other or the occlusion is occurring due to other foreground objects, still the proposed algorithm can perform well in such situations. Furthermore, we consider the distance of object from camera for an adaptive search range to deal with the people movement issue. Although foreground is similar to the background in some conditions, the proposed algorithm can still detect the object well. We also propose an embedded data compression technique, which does not only reduce the computational complexity, but also achieves high compression rate. The overall system is developed in a platform-based system-on-a-programmable-chip for demonstration of result. In VLSI implementation results, the logical gate count is 139.890 K and the throughput of foreground detection is 6403 K pixels/s.
Autors: Tsung-Han Tsai;Chih-Hao Chang;
Appeared in: IEEE Sensors Journal
Publication date: Sep 2017, volume: 17, issue:18, pages: 6077 - 6089
Publisher: IEEE
 
» Harmonic Suppression and Stability Enhancement for Parallel Multiple Grid-Connected Inverters Based on Passive Inverter Output Impedance
Abstract:
In this paper, the inverter output impedance is passivized for solving the harmonic and the stability problems in the multiparallel inverters. The harmonics are easily aroused because of the disturbances, and the system stability is challenged by the grid impedance. Based on the simplified equivalent impedance model, the two problems are analyzed in the low-frequency (LF) band and the high-frequency (HF) band, respectively. Aiming at improving the LF performance, the weighted-proportional grid voltage feedforward and the harmonic quasi-resonant controller with phase compensation are proposed. The dynamic performance is enhanced with an additional current reference generation scheme. In order to improve the HF performance, a novel digital phase lead filter which brings the system back to a minimum-phase case is proposed. By the proposed control method, the high modulus of each inverter output impedance is guaranteed, while the phase angles of over the entire frequency band are avoided to be lower than −90°. The experiments based on four-parallel inverters have been conducted to validate the effectiveness of the proposed control method.
Autors: Qiang Qian;Shaojun Xie;Liuliu Huang;Jinming Xu;Zhao Zhang;Binfeng Zhang;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Sep 2017, volume: 64, issue:9, pages: 7587 - 7598
Publisher: IEEE
 
» Harmonising Coexistence of Machine Type Communications With Wi-Fi Data Traffic Under Frame-Based LBT
Abstract:
The existence of relatively long LTE data blocks within the licensed-assisted access (LAA) framework results in bursty machine-type communications (MTC) packet arrivals, which cause system performance degradation and present new challenges in Markov modeling. We develop an embedded Markov chain to characterize the dynamic behavior of the contention arising from bursty MTC and Wi-Fi data traffic in the LAA framework. Our theoretical model reveals a high-contention phenomenon caused by the bursty MTC traffic, and quantifies the resulting performance degradation for both MTC and Wi-Fi data traffic. The Markov model is further developed to evaluate three potential solutions aiming to alleviate the contention. Our analysis shows that simply expanding the contention window, although successful in reducing congestion, may cause unacceptable MTC data loss. A TDMA scheme instead achieves better MTC packet delivery and overall throughput, but requires centralized coordination. We propose a distributed scheme that randomly spreads the MTC access processes through the available time period. Our model results, validated by simulations, demonstrate that the random spreading solution achieves a near TDMA performance, while preserving the distributed nature of the Wi-Fi protocol. It alleviates the MTC traffic contention and improves the overall throughput by up to 10%.
Autors: Gordon J. Sutton;Ren Ping Liu;Y. Jay Guo;
Appeared in: IEEE Transactions on Communications
Publication date: Sep 2017, volume: 65, issue:9, pages: 4000 - 4011
Publisher: IEEE
 
» HEAL-WEAR: An Ultra-Low Power Heterogeneous System for Bio-Signal Analysis
Abstract:
Personalized healthcare devices enable low-cost, unobtrusive and long-term acquisition of clinically relevant biosignals. These appliances, termed wireless body sensor nodes (WBSNs), are fostering a revolution in health monitoring for patients affected by chronic ailments. Nowadays, WBSNs often embed complex digital processing routines, which must be performed within an extremely tight energy budget. Addressing this challenge, in this paper, we introduce a novel computing architecture devoted to the ultra-low power analysis of biosignals. Its heterogeneous structure comprises multiple processors interfaced with a shared acceleration resource, implemented as a coarse-grained reconfigurable array (CGRA). The CGRA mesh effectively supports the execution of the intensive loops that characterize biosignal analysis applications, while requiring a low reconfiguration overhead. Moreover, both the processors and the reconfigurable fabric feature single-instruction/multiple data (SIMD) execution modes to increase efficiency when multiple data streams are concurrently processed. The run-time behavior on the system is orchestrated by a lightweight hardware mechanism, which concurrently synchronizes processors for SIMD execution and regulates access to the reconfigurable accelerator. By jointly leveraging run-time reconfiguration and SIMD execution, the illustrated heterogeneous system achieves, when executing complex biosignal analysis applications, speedups of up to on the considered kernels and up to 37.2% overall energy savings, with respect to an ultra-low power multi-core platform, which does not feature CGRA acceleration.
Autors: Loris Duch;Soumya Basu;Rubén Braojos;Giovanni Ansaloni;Laura Pozzi;David Atienza;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Sep 2017, volume: 64, issue:9, pages: 2448 - 2461
Publisher: IEEE
 
» Heterogeneous Multiscale Method for Multirate Railway Traction Systems Analysis
Abstract:
In this paper, a general mathematical framework for implementing multirate analysis in railway traction systems by means of the heterogeneous multiscale methods is presented. The proposed approach considers the bidirectional interaction between the trains and the electrical feeding system preserving the intrinsic coupling between electrical and mechanical variables. The procedure for accommodating different models with different dynamics and time scales is revealed, tested, and validated by means of a realistic case of study.
Autors: Pablo Arboleya;
Appeared in: IEEE Transactions on Intelligent Transportation Systems
Publication date: Sep 2017, volume: 18, issue:9, pages: 2575 - 2580
Publisher: IEEE
 
» Hiding Hardware Trojan Communication Channels in Partially Specified SoC Bus Functionality
Abstract:
On-chip bus implementations must be bug-free and secure to provide the functionality and performance required by modern system-on-a-chip (SoC) designs. Regardless of the specific topology and protocol, bus behavior is never fully specified, meaning there exist cycles/conditions where some bus signals are irrelevant, and ignored by the verification effort. We highlight the susceptibility of current bus implementations to Hardware Trojans hiding in this partially specified behavior, and present a model for creating a covert Trojan communication channel between SoC components for any bus topology and protocol. By only altering existing bus signals during the period where their behaviors are unspecified, the Trojan channel is very difficult to detect. We give Trojan channel circuitry specifics for AMBA AXI4 and advanced peripheral bus (APB), then create a simple system comprised of several master and slave units connected by an AXI4-Lite interconnect to quantify the overhead of the Trojan channel and illustrate the ability of our Trojans to evade a suite of protocol compliance checking assertions from ARM. We also create an SoC design running a multiuser Linux OS to demonstrate how a Trojan communication channel can allow an unprivileged user access to root-user data. We then outline several detection strategies for this class of Hardware Trojan.
Autors: Nicole Fern;Ismail San;Çetin Kaya Koç;Kwang-Ting Tim Cheng;
Appeared in: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Publication date: Sep 2017, volume: 36, issue:9, pages: 1435 - 1444
Publisher: IEEE
 
» Hierarchical Context Modeling for Video Event Recognition
Abstract:
Current video event recognition research remains largely target-centered. For real-world surveillance videos, target-centered event recognition faces great challenges due to large intra-class target variation, limited image resolution, and poor detection and tracking results. To mitigate these challenges, we introduced a context-augmented video event recognition approach. Specifically, we explicitly capture different types of contexts from three levels including image level, semantic level, and prior level. At the image level, we introduce two types of contextual features including the appearance context features and interaction context features to capture the appearance of context objects and their interactions with the target objects. At the semantic level, we propose a deep model based on deep Boltzmann machine to learn event object representations and their interactions. At the prior level, we utilize two types of prior-level contexts including scene priming and dynamic cueing. Finally, we introduce a hierarchical context model that systematically integrates the contextual information at different levels. Through the hierarchical context model, contexts at different levels jointly contribute to the event recognition. We evaluate the hierarchical context model for event recognition on benchmark surveillance video datasets. Results show that incorporating contexts in each level can improve event recognition performance, and jointly integrating three levels of contexts through our hierarchical model achieves the best performance.
Autors: Xiaoyang Wang;Qiang Ji;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Sep 2017, volume: 39, issue:9, pages: 1770 - 1782
Publisher: IEEE
 
» Hierarchical Contextual Attention Recurrent Neural Network for Map Query Suggestion
Abstract:
The query logs from an on-line map query system provide rich cues to understand the behaviors of human crowds. With the growing ability of collecting large scale query logs, the query suggestion has been a topic of recent interest. In general, query suggestion aims at recommending a list of relevant queries w.r.t. users' inputs via an appropriate learning of crowds' query logs. In this paper, we are particularly interested in map query suggestions (e.g., the predictions of location-related queries) and propose a novel model Hierarchical Contextual Attention Recurrent Neural Network (HCAR-NN) for map query suggestion in an encoding-decoding manner. Given crowds map query logs, our proposed HCAR-NN not only learns the local temporal correlation among map queries in a query session (e.g., queries in a short-term interval are relevant to accomplish a search mission), but also captures the global longer range contextual dependencies among map query sessions in query logs (e.g., how a sequence of queries within a short-term interval has an influence on another sequence of queries). We evaluate our approach over millions of queries from a commercial search engine (i.e., Baidu Map). Experimental results show that the proposed approach provides significant performance improvements over the competitive existing methods in terms of classical metrics (i.e., Recall@K and MRR) as well as the prediction of crowds' search missions.
Autors: Jun Song;Jun Xiao;Fei Wu;Haishan Wu;Tong Zhang;Zhongfei Mark Zhang;Wenwu Zhu;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Sep 2017, volume: 29, issue:9, pages: 1888 - 1901
Publisher: IEEE
 
» High Dynamic Range Imaging Technology [Lecture Notes]
Abstract:
In this lecture note, we describe high dynamic range (HDR) imaging systems. Such systems are able to represent luminances of much larger brightness and, typically, a larger range of colors than conventional standard dynamic range (SDR) imaging systems. The larger luminance range greatly improves the overall quality of visual content, making it appear much more realistic and appealing to observers. HDR is one of the key technologies in the future imaging pipeline, which will change the way the digital visual content is represented and manipulated today.
Autors: Alessandro Artusi;Thomas Richter;Touradj Ebrahimi;Rafal K. Mantiuk;
Appeared in: IEEE Signal Processing Magazine
Publication date: Sep 2017, volume: 34, issue:5, pages: 165 - 172
Publisher: IEEE
 
» High Energy Resolution Hyperspectral X-Ray Imaging for Low-Dose Contrast-Enhanced Digital Mammography
Abstract:
Contrast-enhanced digital mammography (CEDM) is an alternative to conventional X-ray mammography for imaging dense breasts. However, conventional approaches to CEDM require a double exposure of the patient, implying higher dose, and risk of incorrect image registration due to motion artifacts. A novel approach is presented, based on hyperspectral imaging, where a detector combining positional and high-resolution spectral information (in this case based on Cadmium Telluride) is used. This allows simultaneous acquisition of the two images required for CEDM. The approach was tested on a custom breast-equivalent phantom containing iodinated contrast agent (Niopam 150®). Two algorithms were used to obtain images of the contrast agent distribution: K-edge subtraction (KES), providing images of the distribution of the contrast agent with the background structures removed, and a dual-energy (DE) algorithm, providing an iodine-equivalent image and a water-equivalent image. The high energy resolution of the detector allowed the selection of two close-by energies, maximising the signal in KES images, and enhancing the visibility of details with the low surface concentration of contrast agent. DE performed consistently better than KES in terms of contrast-to-noise ratio of the details; moreover, it allowed a correct reconstruction of the surface concentration of the contrast agent in the iodine image. Comparison with CEDM with a conventional detector proved the superior performance of hyperspectral CEDM in terms of the image quality/dose tradeoff.
Autors: Silvia Pani;Sarene C. Saifuddin;Filipa I.M. Ferreira;Nicholas Henthorn;Paul Seller;Paul J. Sellin;Philipp Stratmann;Matthew C. Veale;Matthew D. Wilson;Robert J. Cernik;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Sep 2017, volume: 36, issue:9, pages: 1784 - 1795
Publisher: IEEE
 
» High Performance Dummy Fill Insertion With Coupling and Uniformity Constraints
Abstract:
In deep-submicron very large scale integration manufacturing, dummy fills are widely applied to reduce topographic variations and improve layout pattern uniformity. However, the introduction of dummy fills may impact the wire electrical properties, such as coupling capacitance. Traditional tile-based method for fill insertion usually results in very large number of fills, which increases the cost of layout storage. In advanced technology nodes, solving the tile-based dummy fill design is more and more expensive. In this paper, we propose a high performance dummy fill insertion framework based on geometric properties to optimize multiple objectives simultaneously, including coupling capacitance, density variations and gradient. The experimental results for ICCAD 2014 contest benchmarks demonstrate the effectiveness of our methods.
Autors: Yibo Lin;Bei Yu;David Z. Pan;
Appeared in: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Publication date: Sep 2017, volume: 36, issue:9, pages: 1532 - 1544
Publisher: IEEE
 
» High Sensitivity and Fast Acquisition Signal Processing Techniques for GNSS Receivers: From fundamentals to state-of-the-art GNSS acquisition technologies
Abstract:
Higher sensitivity and faster acquisition can be two conflicting goals for a global navigation satellite system (GNSS) acquisition function, and both of the goals must be considered in the development of GNSS signal processing techniques to meet the demands for location-based services (LBSs) in GNSS-challenged environments. This article introduces the fundamentals of GNSS acquisition functions and various GNSS acquisition techniques for new GNSS signals and investigates recent acquisition techniques achieving high sensitivity and fast acquisition. It provides useful information for engineers who study state-of-the-art GNSS signal acquisition techniques and want to understand the challenges involved in improving GNSS acquisition sensitivity and acquisition time.
Autors: Seung-Hyun Kong;
Appeared in: IEEE Signal Processing Magazine
Publication date: Sep 2017, volume: 34, issue:5, pages: 59 - 71
Publisher: IEEE
 
» High Spatial Resolution Radiation Detection Using Distributed Fiber Sensing Technique
Abstract:
This paper studies perspectives on using optical fibers and distributed fiber sensing schemes to perform real-time-distributed gamma-ray radiation sensing with high spatial resolution. The radiation-induced optical property changes of aluminum-doped fibers were studied using cobalt-60 sources. The distributed optical loss of the aluminum-doped fiber was characterized using the Rayleigh backscattering optical frequency domain reflectometry (Rayleigh OFDR). The optical loss of unprotected fiber under various gamma dose rates remains linear up to 100 grays (Gy). Using the gamma radiation-sensitive fiber, the localized optical loss measured by the Rayleigh OFDR was used to map the accumulated gamma radiation dosage on the entire surface of the cylinder with a 1-cm spatial resolution. Using electrical cables as a ubiquitous sensor platforms for fiber sensor deployment, this paper explores the potential for multifunctional distributed fiber sensor by integrating distributed fiber temperature and gamma ionizing radiation sensors in electrical cables for multifunctional measurements to improve the safety of nuclear power systems at both the component and system levels. As sensors that can readily be embedded in a wide variety of materials and structures, radiation-sensitive fibers can be low-cost and highly flexible tool to gauge the performance degradation and longevity of materials and components used in the nuclear power systems.
Autors: Mohamed A. S. Zaghloul;Aidong Yan;Rongzhang Chen;Ming-Jun Li;Robert Flammang;Michael Heibel;Kevin P. Chen;
Appeared in: IEEE Transactions on Nuclear Science
Publication date: Sep 2017, volume: 64, issue:9, pages: 2569 - 2577
Publisher: IEEE
 
» High-Dimensional Computing as a Nanoscalable Paradigm
Abstract:
We outline a model of computing with high-dimensional (HD) vectors—where the dimensionality is in the thousands. It is built on ideas from traditional (symbolic) computing and artificial neural nets/deep learning, and complements them with ideas from probability theory, statistics, and abstract algebra. Key properties of HD computing include a well-defined set of arithmetic operations on vectors, generality, scalability, robustness, fast learning, and ubiquitous parallel operation, making it possible to develop efficient algorithms for large-scale real-world tasks. We present a 2-D architecture and demonstrate its functionality with examples from text analysis, pattern recognition, and biosignal processing, while achieving high levels of classification accuracy (close to or above conventional machine-learning methods), energy efficiency, and robustness with simple algorithms that learn fast. HD computing is ideally suited for 3-D nanometer circuit technology, vastly increasing circuit density and energy efficiency, and paving a way to systems capable of advanced cognitive tasks.
Autors: Abbas Rahimi;Sohum Datta;Denis Kleyko;Edward Paxon Frady;Bruno Olshausen;Pentti Kanerva;Jan M. Rabaey;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Sep 2017, volume: 64, issue:9, pages: 2508 - 2521
Publisher: IEEE
 
» High-Efficiency Filter-Integrated Class-F Power Amplifier Based on Dielectric Resonator
Abstract:
In this letter, a high-efficiency filter-integrated class-F power amplifier (PA) is presented. High-Q-factor dielectric resonator (DR) filter is employed as the output matching network of the class-F PA. Theoretical analysis is carried out to guide the impedance transformation from to that desired by the transistor at the operating frequency and the harmonic ones. Two transmission zeros are generated by the DR filter for realizing good skirt selectivity. Besides, metal cavity of the DR filter acts as heat sink for the transistor. For demonstration, a filter-integrated PA operating at 1.88 GHz is implemented. Comparison is made to show the advantages of this letter.
Autors: Jin-Xu Xu;Xiu Yin Zhang;Xiao-Qu Song;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Sep 2017, volume: 27, issue:9, pages: 827 - 829
Publisher: IEEE
 
» High-Frequency Electromagnetic Induction Sensing of Nonmetallic Materials
Abstract:
We introduce a frequency-domain electromagnetic induction (EMI) instrument for detection and classification of objects with either high () or intermediate () electrical conductivity. While high conductivity metallic targets exhibit a quadrature peak response for frequencies in a traditional EMI regime under 100 kHz, the response of intermediate conductivity objects manifests at higher frequencies, between 100 kHz and 15 MHz. Materials such as carbon fiber or conducting salt solutions exhibit conductivities in this intermediate range and are undetectable by traditional low-frequency EMI instruments. To detect these intermediate conductivity targets, we developed a high-frequency EMI (HFEMI) instrument with a frequency range extended to 15 MHz. The HFEMI instrument requires novel hardware considerations, coil design, and data processing schemes. Most importantly, the wire lengths of transmit and receive coils are shorter than those of traditional frequency EMI sensors, so that the phase on the transmit and receive coils is nearly constant. We present the hardware and software aspects of the HFEMI instrument along with preliminary data, demonstrating its ability to detect intermediate conductive objects.
Autors: John Brevard Sigman;Benjamin E. Barrowes;Kevin O’Neill;Yinlin Wang;Janet E. Simms;Hollis H. Bennett;Donald E. Yule;Fridon Shubitidze;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Sep 2017, volume: 55, issue:9, pages: 5254 - 5263
Publisher: IEEE
 
» High-Mobility OFDM Downlink Transmission With Large-Scale Antenna Array
Abstract:
In this correspondence, we propose a new receiver design for high-mobility orthogonal frequency-division multiplexing (OFDM) downlink transmissions with a large-scale antenna array. The downlink signal experiences the challenging fast time-varying propagation channel. The time-varying nature originates from the multiple carrier frequency offsets (CFOs) due to the transceiver oscillator frequency offset (OFO) and multiple Doppler shifts. Let the received signal first go through a carefully designed beamforming network, which could separate multiple CFOs in the spatial domain with a sufficient number of receive antennas. A joint estimation method for the Doppler shifts and the OFO is further developed. Then, the conventional single-CFO compensation and channel estimation method can be carried out for each beamforming branch. The proposed receiver design avoids the complicated time-varying channel estimation, which differs a lot from the conventional methods. More importantly, the proposed scheme can be applied to the commonly used time-varying channel models, such as the Jakes’ channel model.
Autors: Wei Guo;Weile Zhang;Pengcheng Mu;Feifei Gao;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Sep 2017, volume: 66, issue:9, pages: 8600 - 8604
Publisher: IEEE
 
» High-Order Divergence-Conforming Constrained Bases for Triangular Cells
Abstract:
This paper presents an algebraic technique for generating arbitrary-order divergence-conforming bases for curvilinear triangular cells. The bases are constructed by enforcing appropriate constraints on a linear combination of general functions and then extracting the desired bases using singular value decompositions. Koornwinder–Dubiner polynomials are chosen as the general function set. Basic constraints are presented to obtain divergence-conforming bases, and additional constraints are presented to further enforce the bases to be Nédélec. Results from a variety of problems are given to show that the bases exhibit high-order convergence and also produce systems that are relatively well conditioned compared to other basis sets.
Autors: John C. Young;Robert J. Adams;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Sep 2017, volume: 65, issue:9, pages: 4717 - 4727
Publisher: IEEE
 
» High-Pass Negative Group Delay RC-Network Impedance
Abstract:
This brief describes a synthesis of high-pass negative group delay (NGD) network impedance. The fundamental expression of the high-pass NGD canonical transfer function is established. Based on the circuit impedance equivalent principle, the high-pass NGD first-order network that is constituted by RC lumped elements is identified. The identified topology basic NGD characteristics are formulated and analyzed. Then, the associated synthesis method in function of the desired NGD optimal level and cutoff frequency is established. The theory is validated by design, simulations, and measurements of proof-of-concept prototypes. A good agreement between the theoretical prediction and experimental results showing high-pass NGD response from 1 MHz with minimal level of about −10 ns is observed. The high-pass NGD function operates at high frequencies with first-order circuit.
Autors: Blaise Ravelo;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Sep 2017, volume: 64, issue:9, pages: 1052 - 1056
Publisher: IEEE
 
» High-Performance Nonvolatile Organic Transistor Memory Using Quantum Dots-Based Floating Gate
Abstract:
A novel nonvolatile floating-gate transistor memory device using CdSe@ZnS quantum dots (QDs) embedded the insulating polymer as a charge-storage layer along with the rational design of device structure is presented. The core–shell structure CdSe@ZnS QDs can efficiently trap both holes and electrons under the applied writing/erasing operations, resulting in a considerable threshold voltage shifts ( over 50 V and forming high-conductance (ON) and low-conductance (OFF) states at a gate voltage of 0 V. The value of threshold voltage shift is controlled by writing and erasing voltages, regardless with source–drain voltages. Furthermore, it exhibits a long retention time (the can maintain 76% at 108 s) and outstanding endurance characteristics (>500 cycles), demonstrating extraordinary stable and reliable memory property. Moreover, a thin layer of Al2O3 was introduced as tunneling dielectric layer which is essential for the high-performance floating-gate transistor memory device. The nonvolatile organic transistor memory devices using QDs-based floating gate show great potential application for high-performance organic memory devices.
Autors: Daobing Hu;Guocheng Zhang;Huihuang Yang;Jun Zhang;Cihai Chen;Shuqiong Lan;Huipeng Chen;Tailiang Guo;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Sep 2017, volume: 64, issue:9, pages: 3816 - 3821
Publisher: IEEE
 
» High-Performance SAW Resonator on New Multilayered Substrate Using LiTaO3 Crystal
Abstract:
To develop the high-performance filters and duplexers required for recent long-term evolution frequency bands in mobile handsets, a surface acoustic wave (SAW) resonator is needed that has a higher quality (Q) and a lower temperature coefficient of frequency (TCF). To achieve this, the authors focused on acoustic energy confinement in the depth direction for a rotated Y-X LiTaO3 (LT) substrate. Characteristics of multilayered substrates with low-impedance and high-impedance layers under LT layer were studied numerically in terms of acoustic energy distribution, phase velocity, coupling coefficient, and temperature characteristics employing a finite-element method simulation. After several calculations, a novel multilayered structure was developed that uses SiO2 for a low-impedance layer and AlN for a high-impedance layer under the thin LT layer. A one-port resonator using the new substrate was fabricated, and its experimental results showed that the developed resonator had a Bode-Q over 4000 and TCF of −8 ppm/°C, which are four times higher than and one-fifth as small as those of a conventional 4° YX-LT SAW resonator, respectively. By applying this technology, a band 25 duplexer with very narrow duplex gap was successfully developed, which shows extremely low insertion loss, steep cutoff characteristics, and stable temperature characteristics.
Autors: Tsutomu Takai;Hideki Iwamoto;Yuichi Takamine;Hisashi Yamazaki;Toshiyuki Fuyutsume;Haruki Kyoya;Takeshi Nakao;Hajime Kando;Masahiro Hiramoto;Takanori Toi;Masayoshi Koshino;Norio Nakajima;
Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Publication date: Sep 2017, volume: 64, issue:9, pages: 1382 - 1389
Publisher: IEEE
 
» High-Performance Stacked Double-Layer N-Channel Poly-Si Nanosheet Multigate Thin-Film Transistors
Abstract:
A high-performance stacked double-layer N-channel poly-Si nanosheet (NS) multigate thin-film transistor (DLNS-TFT) is demonstrated successfully. The proposed device has low cost, is easy to fabricate, and is compatible with Si MOSFET, active-matrix organic light-emitting diode, and active-matrix liquid-crystal display fabrication. This DLNS-TFT reveals high driving current (> 105 A/um), high Ion/Ioff ratio (> 108), high mobility (42 cm2/Vs), and low parasitic resistance, when compared with single-layer nanosheet TFT. The DLNS-TFT also has a high density and satisfies the driving current monolithic multilayer 3-D IC in the ITRS 2015 version technology roadmap to the year 2030.
Autors: Lun-Chun Chen;Yu-Ru Lin;Yu-Shuo Chang;Yung-Chun Wu;
Appeared in: IEEE Electron Device Letters
Publication date: Sep 2017, volume: 38, issue:9, pages: 1256 - 1258
Publisher: IEEE
 
» High-Power ${X}$ -Band 5-b GaN Phase Shifter With Monolithic Integrated E/D HEMTs Control Logic
Abstract:
A high-power -band GaN-based 5-b digital phase shifter with control logic circuit on-chip is demonstrated for the first time, which is implemented with monolithic integrated GaN E/D HEMTs fabrication process. Gate trench etching together with Al2O3 as gate dielectric is used to form the gate of the E-mode GaN HEMTs. Switched filter and high-pass/low-pass topology are used to design the 11.25°/22.5° and 45°/90°/180° phase shifters, respectively. A novel three stages control logic circuit is described and characterized. The fabricated 5-b phase shifter demonstrates an rms phase error less than 4.5°, an rms amplitude error less than 0.6 dB, an insertion loss less than 11 dB, and an input–output return loss better than −10 dB across 8.5–11.5 GHz for all 32 states. In addition, the phase shifter exhibits a typical input power of 34.8 dBm in the continuous wave power handling capability measurement at 9 GHz.
Autors: Weijun Luo;Hui Liu;Zongjing Zhang;Pengpeng Sun;Xinyu Liu;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Sep 2017, volume: 64, issue:9, pages: 3627 - 3633
Publisher: IEEE
 
» High-Power High-Isolation RF-MEMS Switches With Enhanced Hot-Switching Reliability Using a Shunt Protection Technique
Abstract:
This paper presents a shunt protection technique to improve the hot-switching reliability of metal-contact radio-frequency microelectromechanical systems (RF-MEMS) switches. The proposed technique places shunt protection contacts in front of the main contact of an RF-MEMS metal contact switch to block RF signal while the main contact is switching ON or OFF. The shunt protection contact creates a local cold-switching condition for the main contact to increase the lifetime of the switch under hot-switching condition. The shunt protection technique can also increase the overall isolation of the switch. To demonstrate the technique, RF-MEMS switches with and without shunt protection were fabricated using all metal process. Compared with the unprotected switch, the protected switch has longer lifetime under hot-switching condition. The protected switch has >100-million cycles and up to 500-million cycles lifetime under the 1-W hot-switching condition, measured in open-air laboratory environment. Besides, the isolation of the shunt-protected switch is 70 dB at 1.0 GHz and 36 dB at 40 GHz, and the insertion loss is 0.30 dB at 1.0 GHz and 0.43 dB at 40 GHz.
Autors: Yuhao Liu;Yusha Bey;Xiaoguang Liu;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Sep 2017, volume: 65, issue:9, pages: 3188 - 3199
Publisher: IEEE
 
» High-Resistivity CMOS SOI Rectenna for Implantable Applications
Abstract:
The design and near-field characterization of an integrated rectenna on Globalfoundries 45-nm CMOS SOI technology are presented. The rectenna is intended for short range (below 8 cm) wireless powering and communication of integrated sensor systems and occupies an area of . Upon utilizing high (low)-resistivity Si substrate, the rectenna provides 1.2 (1.25) mW of dc power 1.1 (1.17) V rectified dc output voltage from a 0.95-GHz source with only 18 (30) dBm power feeding a horn antenna with 6-dB gain placed at a short distance (<5 mm) from the antenna. Efficient wireless power transfer at various applied powers and distances and through a 1-cm-thick chicken breast is demonstrated.
Autors: Alice Yi-Szu Jou;Reza Azadegan;Saeed Mohammadi;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Sep 2017, volume: 27, issue:9, pages: 854 - 856
Publisher: IEEE
 
» High-Sensitivity Gas-Pressure Sensor Based on Fiber-Tip PVC Diaphragm Fabry–Pérot Interferometer
Abstract:
We demonstrate a novel polyvinyl chloride (PVC) diaphragm-based fiber-tip Fabry–Perot interferometer for gas-pressure measurements with ultrahigh sensitivity. The PVC diaphragm has been coated to the end facet of a well-cut standard single-mode fiber by use of a plastic welder. An ultrahigh-pressure sensitivity of ∼65.5 nm/MPa at 1565 nm and a low-temperature cross sensitivity of ∼–5.5 kPa/°C have been experimentally demonstrated. The proposed sensor has advantages of high pressure sensitivity, miniature size, low cost, and easy fabrication.
Autors: Zhe Zhang;Changrui Liao;Jian Tang;Zhiyong Bai;Kuikui Guo;Maoxiang Hou;Jun He;Ying Wang;Shen Liu;Feng Zhang;Yiping Wang;
Appeared in: Journal of Lightwave Technology
Publication date: Sep 2017, volume: 35, issue:18, pages: 4067 - 4071
Publisher: IEEE
 
» High-Temperature RF Material Characterization Using a Dual-Chambered Rectangular Waveguide Fixture
Abstract:
A rectangular waveguide (RWG) fixture is proposed for the high-temperature RF characterization of materials. Composed of two RWGs in a side-by-side or over–under orientation, the new apparatus permits the calibration and specimen measurements to be collected simultaneously reducing high-temperature measurement time by two full days over the traditional method. In addition, the permittivity and permeability, determined from measured -parameters, are independent of sample position and can be found in closed form. The design and construction of the dual-chambered RWG fixture are detailed. The closed-form, position-independent, permittivity and permeability extraction method is also discussed. Finally, high-temperature material characterization experiments are performed to validate the fixture. The errors in permittivity and permeability are estimated assuming uncertainties in sample thickness and measured -parameters.
Autors: Andrew E. Bogle;Milo W. Hyde;Michael J. Havrilla;Jeffrey S. Sovern;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Sep 2017, volume: 66, issue:9, pages: 2422 - 2427
Publisher: IEEE
 
» High-Temperature Superconducting Magnetic Levitation Vehicles: Dynamic Characteristics While Running on a Ring Test Line
Abstract:
In the long-distance operation of the high-temperature superconducting (HTS) magnetic levitation (maglev) systems, the dynamic characteristics of the vehicle are closely related to its security and stationarity, which require in-depth research to ensure its safe operation. Thus, we investigated the dynamic characteristics of the HTS maglev and assessed its safety and stationarity when running on a ring test line. In the experiments, the important parameters related to safety are lateral displacement (LD) and levitation height (LH). Results show that an appropriate low field-cooling height (FCH) is beneficial for its safe operation, and the maximum LD (MLD) should be considered in vehicle designs. Moreover, in other experiments, we tested the vibration acceleration of the HTS maglev vehicle using acceleration sensors and assessed its stationarity according to the Chinese National Standard GB5599-85, which is specifically published to assess the stationarity and security of railway vehicles by the China Ministry of Railways. The stationarity of the HTS maglev vehicle running on the ring test line is of good grade. When the secondary suspension and appropriate measures of vibration reduction are considered, the stationarity will be greatly improved.
Autors: Zigang Deng;Jipeng Li;Weihua Zhang;Yanfeng Gou;Yu Ren;Jun Zheng;
Appeared in: IEEE Vehicular Technology Magazine
Publication date: Sep 2017, volume: 12, issue:3, pages: 95 - 102
Publisher: IEEE
 
» High-TV Based CS Framework Using MAP Estimator for SAR Image Enhancement
Abstract:
Synthetic aperture radar (SAR) images have two main problems: Degradation by speckle that causes low-contrast images and misinterpretation, and the large amount of data that makes the computation time an important issue. In addition to denoising, it is necessary to recover the missing data due to errors in the onboard SAR equipment, downlink equipment, and ground data registration. In this paper, we propose a method using high-order total variation (High-TV) denoising in compressive sensing (CS) framework, based on maximum a posteriori (MAP) estimation to simultaneously denoise and recover the large-size, complex-valued SAR images. Experiments on RADARSAT-1 raw data showed that the proposed method, called MAP High-TV, can suppress the speckle effectively without exhibiting a staircase effect on the images, and perfectly recovers the missed data. The performance comparison among the proposed method, MAP-MIDAL (the pioneer CS-based method), and three state of the art filters (NSM, POTDF and FANS), explores the capability of MAP High-TV for both denoising and recovering the complex-valued SAR images.
Autors: Haybert Markarian;Sedigheh Ghofrani;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Sep 2017, volume: 10, issue:9, pages: 4059 - 4073
Publisher: IEEE
 
» Highly Sensitive Bilayer Phosphorene Nanoribbon Pressure Sensor Based on the Energy Gap Modulation Mechanism: A Theoretical Study
Abstract:
In this letter, bilayer phosphorene and its corresponding nanoribbons are utilized as pressure sensors due to their modulation mechanism under normal compressive strain. A multiscale simulation flow is implemented from the band structure to the current calculations. To obtain exact tight binding (TB) Hamiltonians and the following current results, unitary Wannier transformations are adopted, and interactions between the four nearest TB neighbors are considered. From the simulations, the sensitivity of the bilayer phosphorene pressure sensor was found to increase exponentially as the pressure increased due to the modulation mechanism. The sensitivity of zigzag bilayer phosphorene nanoribbons (zBPNRs) was further improved. At low pressures, the improvements are mainly derived from the restriction of the flat region. The sensitivities of zBPNRs reached KPa under a pressure of approximately 2.5 GPa, which indicates their potential application in pressure sensor arrays.
Autors: Yawei Lv;Qijun Huang;Sheng Chang;Hao Wang;Jin He;
Appeared in: IEEE Electron Device Letters
Publication date: Sep 2017, volume: 38, issue:9, pages: 1313 - 1316
Publisher: IEEE
 
» Highly Sensitive Temperature Sensing Probe Based on Deviation S-Shaped Microfiber
Abstract:
A deviation S-shaped microfiber was proposed and packaged in a capillary by glycerin solution. The high-temperature sensitivity performance was experimentally demonstrated. With the decrease in ambient temperature from 73.05 °C to 23.46 °C, the resonant dip on the transmission spectra red-shifts continually due to the co-operation between the refractive index increase of glycerol and the thermal expansion of packaging materials. The high sensitivity of ~11 nm/°C promises high-sensitive monitoring of the slight temperature fluctuation in some specific biological and chemical reaction process.
Autors: Jin Li;Qin Nie;Liting Gai;Hanyang Li;Haifeng Hu;
Appeared in: Journal of Lightwave Technology
Publication date: Sep 2017, volume: 35, issue:17, pages: 3699 - 3704
Publisher: IEEE
 
» Highly Sensitive, Fast-Responding, and Stable Photodetector Based on ALD-Developed Monolayer TiO2
Abstract:
In this paper, high-quality wafer-scale monolayer TiO2 films were synthesized via atomic layer deposition and their main characteristics were investigated. The deposited TiO2 monolayer films were subsequently utilized in photodetectors (PDs), which demonstrated considerable optoelectronic performance with ultrafast response (30 μs) and recovery (63 μs) time, high on/off ratio (220), good reversibility, and great long-term stability (less than 2% variation after 1000 cycles). The photoresponsivity (Rλ) and external quantum efficiency of 0.352 A/W and 109.12% were, respectively, attained at the incident laser power density of 118 mW/cm2 () and . These photoelectrical characteristics of the monolayer TiO2-based PDs confirmed that this TiO2 nanostructure could be an excellent candidate for various smart and portable applications such as UV-detection devices, photoswitches, high-speed optical communications, and image sensors.
Autors: Mohammad Karbalaei Akbari;Zhenyin Hai;Stephen Depuydt;Eugene Kats;Jie Hu;Serge Zhuiykov;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Sep 2017, volume: 16, issue:5, pages: 880 - 887
Publisher: IEEE
 
» HNIP: Compact Deep Invariant Representations for Video Matching, Localization, and Retrieval
Abstract:
With emerging demand for large-scale video analysis, MPEG initiated the compact descriptor for video analysis (CDVA) standardization in 2014. Beyond handcrafted descriptors adopted by the current MPEG-CDVA reference model, we study the problem of deep learned global descriptors for video matching, localization, and retrieval. First, inspired by a recent invariance theory, we propose a nested invariance pooling (NIP) method to derive compact deep global descriptors from convolutional neural networks (CNNs), by progressively encoding translation, scale, and rotation invariances into the pooled descriptors. Second, our empirical studies have shown that a sequence of well designed pooling moments (e.g., max or average) may drastically impact video matching performance, which motivates us to design hybrid pooling operations via NIP (HNIP). HNIP has further improved the discriminability of deep global descriptors. Third, the technical merits and performance improvements by combining deep and handcrafted descriptors are provided to better investigate the complementary effects. We evaluate the effectiveness of HNIP within the well-established MPEG-CDVA evaluation framework. The extensive experiments have demonstrated that HNIP outperforms the state-of-the-art deep and canonical handcrafted descriptors with significant mAP gains of 5.5% and 4.7%, respectively. In particular the combination of HNIP incorporated CNN descriptors and handcrafted global descriptors has significantly boosted the performance of CDVA core techniques with comparable descriptor size.
Autors: Jie Lin;Ling-Yu Duan;Shiqi Wang;Yan Bai;Yihang Lou;Vijay Chandrasekhar;Tiejun Huang;Alex Kot;Wen Gao;
Appeared in: IEEE Transactions on Multimedia
Publication date: Sep 2017, volume: 19, issue:9, pages: 1968 - 1983
Publisher: IEEE
 
» Hole-Trapping Process at Al2O3/GaN Interface Formed by Atomic Layer Deposition
Abstract:
The hysteresis of the capacitance–voltage (C–V) characteristics of an Al2O3/n-GaN metal–insulator–semiconductor structure was evaluated under light (white LED)-irradiation and dark conditions. The hysteresis was not observed under the dark condition but was observed under the light-irradiation condition. The GaN surface was completely depleted in negative bias under the dark condition. The C–V characteristics indicated that the hysteresis is caused by hole trapping under the LED irradiation condition and that the holes are generated in the n-GaN surface by LED irradiation and subsequently injected into the Al2O3 films. When the holes are generated in the depletion region of GaN for any reason, such as a short generation lifetime, they can be trapped in the Al2O3 films.
Autors: Akinobu Teramoto;Masaya Saito;Tomoyuki Suwa;Tetsuo Narita;Rihito Kuroda;Shigetoshi Sugawa;
Appeared in: IEEE Electron Device Letters
Publication date: Sep 2017, volume: 38, issue:9, pages: 1309 - 1312
Publisher: IEEE
 
» Horn Antenna With Reconfigurable Beam-Refraction and Polarization Based on Anisotropic Huygens Metasurface
Abstract:
In this paper, we present a new horn antenna that can mechanically reconfigure the beam direction and polarization by combining a traditional linearly polarized horn antenna with an anisotropic Huygens metasurface. Three layers of Jerusalem-cross structures are integrated in a dielectric substrate to form the anisotropic Huygens metasurface; the entire structure has a thickness of about one fifteenth the working wavelength. By placing the metasurface in front of a traditional linearly polarized horn antenna, the main beam of the horn antenna is steered to a predetermined direction. Furthermore, the direction and polarization of the main beam are reconfigurable by rotating the anisotropic Huygens metasurface. The measured results of the antenna confirm the simulated results. Possible applications of the presented antenna include radar detection, base-station communications, and satellite communications.
Autors: Xiang Wan;Lei Zhang;Sheng Li Jia;Jia Yuan Yin;Tie Jun Cui;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Sep 2017, volume: 65, issue:9, pages: 4427 - 4434
Publisher: IEEE
 
» How the Brain Processes Multimodal Technical Instructions (Remley, D; 2015) [Book review]
Abstract:
Crossing disciplinary boundaries is a common practice for today’s technical writer. The author offers an insightful look at how neurobiological and multimodal rhetorical concepts can inform instructional document design to improve learning. This book addresses an interdisciplinary audience of academic and industry professionals involved in employee training or instructional training material design. The goal here is to answer the question, “How does one learn new technical concepts?. To answer this, the book bridges theoretical concepts in the seemingly dissimilar fields of cognitive psychology, neurobiology, and rhetoric. While there is still much to be discussed within this vast interdisciplinary conversation, the author's synthesis and his resulting analysis model hold workplace and pedagogical value by providing an entry point through a shared goal: cognitive gain through effective technical instructional materials.
Autors: Sarah Johnson;
Appeared in: IEEE Transactions on Professional Communication
Publication date: Sep 2017, volume: 60, issue:3, pages: 330 - 331
Publisher: IEEE
 
» Human Motion Tracking by Multiple RGBD Cameras
Abstract:
The advent of low-cost depth cameras, such as the Microsoft Kinect in the consumer market, has made many indoor applications and games based on motion tracking available to the everyday user. However, it is a large challenge to track human motion via such a camera because of its low-quality images, missing depth values, and noise. In this paper, we propose a novel human motion capture method based on a cooperative structure of multiple low-cost RGBD cameras, which can effectively avoid these problems. This structure can also manage the problem of body occlusions that appears when a single camera is used. Moreover, the whole process does not require training data, which makes this approach easily deployed and reduces operation time. We use the color image, depth image, and point cloud acquired in each view as the data source, and an initial pose is extracted in our optimization framework by aligning multiple point clouds from different cameras. The pose is dynamically updated by combining a filtering approach with a Markov model to estimate new poses in video streams. To verify the efficiency and robustness of our approach, we capture a wide variety of human actions via three cameras in indoor scenes and compare the tracking results of the proposed method to those of the current state-of-the-art methods. Moreover, our system is tested on more complex situations, in which multiple humans move within a scene, possibly occluding each other to some extent. The actions of multiple humans are tracked simultaneously, which would assist group behavior analysis.
Autors: Zhenbao Liu;Jinxin Huang;Junwei Han;Shuhui Bu;Jianfeng Lv;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Sep 2017, volume: 27, issue:9, pages: 2014 - 2027
Publisher: IEEE
 
» Humidity-Dependent Synaptic Plasticity for Proton Gated Oxide Synaptic Transistor
Abstract:
Indium-tin-oxide synaptic transistors using proton conducting nanogranular phosphorosilicate glass as gate dielectric are fabricated. Humidity-dependent proton gating behaviors are observed. Moreover, synaptic plasticities are mimicked on the proton gated oxide synaptic transistors. Interestingly, enhanced synaptic facilitation is observed at higher relative humidity originated from the strengthened proton gating. An oxide synaptic transistor with humidity-dependent synaptic plasticities may find potential applications in neuromorphic platforms.
Autors: Li Qiang Guo;Juan Wen;Li Qiang Zhu;Yang Ming Fu;Hui Xiao;
Appeared in: IEEE Electron Device Letters
Publication date: Sep 2017, volume: 38, issue:9, pages: 1248 - 1251
Publisher: IEEE
 
» Hybrid Acoustic Noise Analysis Approach of Conventional and Mutually Coupled Switched Reluctance Motors
Abstract:
This paper presents a method to calculate the acoustic noise of conventional switched reluctance motor (CSRM) and mutually coupled switched reluctance motor (MCSRM). This method is based on dynamic electromagnetic models, combined with analytical estimation of the stator eigenmodes and radiation efficiency, considering the switching effects and frame effects. The proposed method is applied to predict and compare the acoustic noise performances of a CSRM and an MCSRM in a wide speed range. The results are validated using commercial finite element analysis software, JMAG for electromagnetics and ACTRAN for acoustics. An acceleration test based on a setup with a 12/8 CSRM is used for experimental validation. Results show that the proposed method can provide reliable prediction of main acoustic noises during acceleration.
Autors: Jianning Dong;James Weisheng Jiang;Brock Howey;Haoding Li;Berker Bilgin;Alan Dorneles Callegaro;Ali Emadi;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Sep 2017, volume: 32, issue:3, pages: 1042 - 1051
Publisher: IEEE
 
» Hybrid Beamforming via the Kronecker Decomposition for the Millimeter-Wave Massive MIMO Systems
Abstract:
Millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) seamlessly integrates two wireless technologies, mmWave communications and massive MIMO, which provides spectrums with tens of GHz of total bandwidth and supports aggressive space division multiple access using large-scale arrays. Though it is a promising solution for next-generation systems, the realization of mmWave massive MIMO faces several practical challenges. In particular, implementing massive MIMO in the digital domain requires hundreds to thousands of radio frequency chains and analog-to-digital converters matching the number of antennas. Furthermore, designing these components to operate at the mmWave frequencies is challenging and costly. These motivated the recent development of the hybrid-beamforming architecture, where MIMO signal processing is divided for separate implementation in the analog and digital domains, called the analog and digital beamforming, respectively. Analog beamforming using a phase array introduces uni-modulus constraints on the beamforming coefficients. They render the conventional MIMO techniques unsuitable and call for new designs. In this paper, we present a systematic design framework for hybrid beamforming for multi-cell multiuser massive MIMO systems over mmWave channels characterized by sparse propagation paths. The framework relies on the decomposition of analog beamforming vectors and path observation vectors into Kronecker products of factors being uni-modulus vectors. Exploiting properties of Kronecker mixed products, different factors of the analog beamformer are designed for either nulling interference paths or coherently combining data paths. Furthermore, a channel estimation scheme is designed for enabling the proposed hybrid beamforming. The scheme estimates the angles-of-arrival (AoA) of data and interference paths by analog beam scanning and data-path gains - y analog beam steering. The performance of the channel estimation scheme is analyzed. In particular, the AoA spectrum resulting from beam scanning, which displays the magnitude distribution of paths over the AoA range, is derived in closed form. It is shown that the inter-cell interference level diminishes inversely with the array size, the square root of pilot sequence length, and the spatial separation between paths, suggesting different ways of tackling pilot contamination.
Autors: Guangxu Zhu;Kaibin Huang;Vincent K. N. Lau;Bin Xia;Xiaofan Li;Sha Zhang;
Appeared in: IEEE Journal on Selected Areas in Communications
Publication date: Sep 2017, volume: 35, issue:9, pages: 2097 - 2114
Publisher: IEEE
 
» Hybrid Bidirectional Wireless EV Charging System Tolerant to Pad Misalignment
Abstract:
Electric vehicles (EVs) are becoming increasingly popular as a means of future transport for sustainable living. However, wireless charging of EVs poses a number of challenges related to interoperability, safety, pad misalignment, etc. In particular, pad misalignments invariably cause changes in system parameters which in turn lead to increase in losses as well as reduction in power throughput, making the charging process long and inefficient. Consequently, wireless charging systems that are less sensitive to pad misalignments have become preferable. This paper, therefore, presents a hybrid wireless power transfer (WPT) system that charges EVs at constant rate despite large misalignments between charging pads. The proposed charging system uses a combination of two different resonant networks to realize a constant and efficient charging process. A mathematical model is also developed, showing as to how the two resonant networks can be combined to compensate for pad misalignments. To demonstrate the validity of the proposed concept as well as the accuracy of the mathematical model, theoretical performance is compared with both simulations and experimental results of a prototype 3.3 kW hybrid bidirectional WPT system. Results clearly indicate that the proposed hybrid WPT system is efficient and offers a constant charging profile over a wide range of spatial (three-dimensional) pad misalignments.
Autors: Lei Zhao;Duleepa J. Thrimawithana;Udaya K. Madawala;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Sep 2017, volume: 64, issue:9, pages: 7079 - 7086
Publisher: IEEE
 
» Hybrid Modulated Active Damping Control for DFIG-Based Wind Farm Participating in Frequency Response
Abstract:
This paper analyzes the influence of the doubly fed induction generator (DFIG) based wind farm (WF) participating in the frequency response (FR) on the oscillation modes of the power system and proposes a hybrid modulated active damping scheme to mitigate the potential power oscillations. The FR control would excite additional lightly damped electro-mechanical oscillation mode and deteriorate the damping for the primary interarea oscillation mode inside the power system. Moreover, the internal damping effect on the turbine torsional oscillation would be weakened resulting shaft damage risk if FR is required by the WF. The frequencies of those modes are usually close to each other. By integrated hybrid multiple active damping loops into the active and reactive power controller of the WF respectively, the damping control on all the oscillation modes can be improved at the same time. The analysis and effectiveness of the proposed scheme in this paper are verified by the time-domain simulations.
Autors: Hua Geng;Xinze Xi;Lu Liu;Geng Yang;Jin Ma;
Appeared in: IEEE Transactions on Energy Conversion
Publication date: Sep 2017, volume: 32, issue:3, pages: 1220 - 1230
Publisher: IEEE
 
» Hybrid Oblique-Angle Deposited ITO/Silver Nanowire Transparent Conductive Electrodes for Brighter Light Emitters
Abstract:
In this paper, hybrid transparent conductive electrodes (TCEs) consisting of oblique-angle deposited indium tin oxide (OAD ITO) and silver nanowires (Ag NWs) were developed forGaN-based light-emitting diodes (LEDs). The 100-nm thick OAD ITO acted as an Ohmic contact to p-GaN with negligible light absorption having optical transmittance as high as approximately 99% at 450 nm, and Ag NWs acted as a favorable current spreader with sheet resistance as low as /sq. Consequently, the hybrid TCEs consisting of OAD ITO and Ag NWs yielded an optical transmittance of 93% at 450 nm, a sheet resistance of 18.9 /sq, and a specific contact resistance of cm2. LEDs fabricated with hybrid TCEs demonstrated improved electrical properties and greater optical output powers than the reference LEDs. This was due to the combined effects of the improved optical transparency, the enhanced current spreading, and the surface roughening effect.
Autors: Minkyung Baek;Munsik Oh;Bhaskar Parida;Min Soo Kim;Jae-Hyun Ryou;Hyunsoo Kim;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Sep 2017, volume: 64, issue:9, pages: 3690 - 3695
Publisher: IEEE
 
» Hybrid Power Combining Rectenna Array for Wide Incident Angle Coverage in RF Energy Transfer
Abstract:
This paper discusses a new design approach that uses hybrid power combining rectenna array in radio frequency (RF) energy transfer systems to receive more energy in a wide incident angle range. A beam-forming matrix and a dc power management network (PMN) are introduced to the hybrid power combining. The normalized dc output power of the proposed hybrid power combining array is compared to the conventional power combining methods with regard to the incident wave angle, and the average received dc power is also calculated and compared. To experimentally verify the proposed hybrid combining array performance, four suspended patch antennas are attached to RF energy receiving architecture. A Butler matrix and quadrature hybrids are used for the beam-forming matrix in a hybrid power combining rectenna array. A reconfigurable voltage doubler rectifier with a dc PMN is used to convert RF energy to dc energy and delivers proper voltage to the load. The measured results of each component are presented. Moreover, an experimental verification using fabricated components for RF energy transfer is presented and the measured received dc output power of conventional and proposed structures is presented and compared.
Autors: Dong-Jin Lee;Soo-Ji Lee;In-June Hwang;Wang-Sang Lee;Jong-Won Yu;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Sep 2017, volume: 65, issue:9, pages: 3409 - 3418
Publisher: IEEE
 
» Hybrid Stochastic-Deterministic Multiperiod DC Optimal Power Flow
Abstract:
Stochastic optimal power flow (OPF) formulations that minimize the expected operating costs over forecast scenarios generally result in lower costs than the standard (deterministic) OPF problem for power systems with significant forecast error, for example, from renewable energy sources. However, this type of stochastic OPF problem is more computationally demanding than the deterministic OPF, and even more so when storage units or ramp-constrained generators are included, as they require solving a multi-period OPF problem. We propose a hybrid method approaching the cost performance of the stochastic OPF problem and the computational burden of the deterministic OPF problem. Our method decomposes the problem into stochastic and deterministic subproblems, and relies on Benders’ Cuts to interface them. We present three versions of the method, which achieve different cost/computational burden trade-offs. The versions can be parametrized so that they scale well with the problem dimension. For one of the versions, we develop a multi-dimensional formulation of the Sandwich Algorithm, which is used to iteratively approximate a convex function. Through a case study using a 118-bus system, we find that our hybrid method achieves between 25% and 81% of the cost improvement of the stochastic OPF, but requires only 12 to 41% of the increased computation time required by the stochastic OPF. Both the hybrid method and the multi-dimensional Sandwich Algorithm can be used for problems outside of the field of power systems.
Autors: Olivier Mégel;Johanna L. Mathieu;Göran Andersson;
Appeared in: IEEE Transactions on Power Systems
Publication date: Sep 2017, volume: 32, issue:5, pages: 3934 - 3945
Publisher: IEEE
 
» Hybrid Synchronized PWM Schemes for Closed-Loop Current Control of High-Power Motor Drives
Abstract:
For high-power drives, switching frequency is usually restricted to several hundred hertz to minimize the switching losses. To maintain the current distortions and torque ripples at a reasonable level, synchronized pulse patterns with half-wave and quarter-wave symmetries are employed. The analytic compensation is derived by Fourier analysis to ensure the proportionality between the voltage reference and the output voltage of an inverter for pulse width modulation (PWM) with low pulse ratio. A simple yet very effective method with varying sampling rate is proposed to maintain synchronization even for fast dynamic processes. The fast and smooth transition between different PWM patterns is achieved by compensating phase angle of the voltage reference through the analysis of stator flux trajectories. The effectiveness of the proposed method is validated on a down-scaled 2.2-kW induction motor drives.
Autors: Haitao Yang;Yongchang Zhang;Guofeng Yuan;Paul D. Walker;Nong Zhang;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Sep 2017, volume: 64, issue:9, pages: 6920 - 6929
Publisher: IEEE
 
» HypAp: A Hypervolume-Based Approach for Refining the Design of Embedded Systems
Abstract:
Designing complex embedded systems requires simultaneous optimization of multiple system performance metrics that can be addressed by applying Pareto-based multiobjective optimization techniques. At the end of this type of optimization process, designers always face Pareto fronts (PFs) including a large number of near-optimal solutions from which selecting the most proper system implementation is potentially infeasible. In this letter, for the first time, we present HypAp, a hypervolume-based automated approach to systematically help designers efficiently choose their preferred solutions after the optimization process. HypAp is a two-stage approach relying on clustering Pareto optimal solutions and then finding a subset of solutions that maximizes the hypervolume by using a genetic algorithm. The performance of HypAp is evaluated through applying HypAp to the PF by the case study of mapping applications on network-on-chip-based heterogeneous MPSoC.
Autors: Rabeh Ayari;Mahdi Nikdast;Imane Hafnaoui;Giovanni Beltrame;Gabriela Nicolescu;
Appeared in: IEEE Embedded Systems Letters
Publication date: Sep 2017, volume: 9, issue:3, pages: 57 - 60
Publisher: IEEE
 
» Hyperspectral Image Classification Based on Multiscale Spatial Information Fusion
Abstract:
In hyperspectral image (HSI) classification, the combination of spectral information and spatial information can be applied to enhance the classification performance. In order to better characterize the variability of spatial features at different scales, we propose a new framework called multiscale spatial information fusion (MSIF). The MSIF consists of three parts: multiscale spatial information extraction, local 1-D embedding (L1-DE), and information fusion. First, spatial filter with different scales is used to extract multiscale spatial information. Then, L1-DE is utilized to map the spectral information and spatial information at different scales into 1-D space, respectively. Finally, the obtained 1-D coordinates are used to label the unlabeled spatial neighbors of the labeled samples. The proposed MSIF captures intrinsic spatial information contained in homogeneous regions of different sizes by multiscale strategy. Since the spatial information at different scales is processed separately in MSIF, the variance of spatial information at different scales can be reflected. The use of L1-DE reduces computational cost by mapping high-dimensional samples into 1-D space. In MSIF, the L1-DE and information fusion are used iteratively, and the iterative process terminates in a finite number of steps. The algorithm analysis demonstrates the effectiveness of the proposed method. The experimental results on four widely used HSI data sets show that the proposed method achieved higher classification accuracies compared with other state-of-the-art spectral–spatial classification methods.
Autors: Hong Li;Yalong Song;C. L. Philip Chen;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Sep 2017, volume: 55, issue:9, pages: 5302 - 5312
Publisher: IEEE
 

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