Electrical and Electronics Engineering publications abstract of: 02-2018 sorted by title, page: 14

» PPMA: Privacy-Preserving Multisubset Data Aggregation in Smart Grid
Abstract:
Privacy-preserving data aggregation has been extensively studied in smart grid. However, almost all existing schemes aggregate the total electricity consumption data of the whole user set, which sometimes cannot meet the fine-grained demands from control center in smart grid. In this paper, we propose a privacy-preserving multisubset data aggregation scheme, named PPMA, in smart grid. PPMA can aggregate users’ electricity consumption data of different ranges, while guaranteeing the privacy of individual users. Detailed security analysis shows that PPMA can protect individual user's electricity consumption privacy against a strong adversary. In addition, extensive experiments results demonstrate that PPMA has less computation overhead and no more extra communication and storage costs.
Autors: Shaohua Li;Kaiping Xue;Qingyou Yang;Peilin Hong;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2018, volume: 14, issue:2, pages: 462 - 471
Publisher: IEEE
 
» Precise Blaze Angle Adjustment of Echelle Grating by Self-Shadowing Rotating Mask
Abstract:
Angular precision of 0.1° for the blaze angle of echelle gratings is an important technical requirement for spectral instruments with echelle gratings. This paper proposes a precise adjustment method for the blaze angle of echelle gratings that are etched or deposited by self-shadowing rotating mask. The blaze angle will decrease or increase when the grating is rotated in beams for etching or deposition, respectively. The blaze angle can be controlled by adjusting the etching or deposition conditions. For the echelle grating with nominal blaze angle of 63.0° and groove density of 52.7 g/mm, the blaze angle was decreased by 0.12° with a maximum etching depth of 19 nm on the blaze facet. Additionally, the blaze angle adjustment precision will be better than 0.02° if the maximum etch depth on the blaze facet is less than 3 nm.
Autors: Bin Sheng;Jiaojiao Fan;Yuanshen Huang;Junjun Guo;Haoyu Lyu;Dawei Zhang;Songlin Zhuang;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 7
Publisher: IEEE
 
» Precise Brightfield Localization Alignment for Fourier Ptychographic Microscopy
Abstract:
Fourier ptychographic microscopy (FPM) is a recently developed microscope technology that overcomes the resolution limit of a low numerical aperture objective lens by employing angular varying illuminations. Combining the concepts of ptychography, synthetic aperture, and phase retrieval, FPM achieves high-resolution, wide-field, and quantitative phase imaging at the same time. In typical FPM systems, the angular varying illuminations are achieved with LED arrays whose positional misalignments bring significant errors in the reconstruction procedure. In previous studies, several LED array alignment methods are developed, which iteratively recover the positional misalignment parameters during the reconstruction. These methods consume additional calculations in FPM reconstruction and may not be practical in other microscopy system. In this work, we represent a preprocessing LED array alignment method by accurately localizing the brightfield area on the sample plane. By applying particle swarm optimization method and random sample consensus method, the global misalignment parameters can be estimated with high accuracy and speed. Both numerical simulations and actual system experiments are carried out to evaluate the effectiveness of our method and the results show that the reconstruction quality of high-resolution images is significantly improved by using our method.
Autors: Jizhou Zhang;Tingfa Xu;Jingdan Liu;Sining Chen;Xing Wang;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 13
Publisher: IEEE
 
» Precise Calibration of Propellant Flow and Forces in Specialized Electric Propulsion Test System
Abstract:
Precise readout values for propellant flow rates obtained from mass flow controllers are vital for the derivation of accurate and reliable figures that are indicative of thruster performance, such as the specific impulse and thruster efficiency. This is exceptionally important in thrusters employed for micropropulsion for orbit maintenance and drag compensation in small satellites, where a small uncertainty and deviation in propellant flow would lead to large errors in derived values. Therefore, it is crucial for researchers engaged in propulsion-based research to ensure that their gas flow controllers are calibrated and verified experimentally to be accurate before engaging in thorough experimental work. In this paper, an experimental method for the practical calibration of propellant feed systems in typical Hall thruster setups is tested. The results yield reliable calibration factors that have been applied for performance correction of miniature Hall thrusters. The corrected propellant flows correlate well with obtained ionization oscillation waveforms, indicating that the presented method for calibration is favorable and dependable for application to ground test facilities for thrust performance qualification.
Autors: Jian Wei Mark Lim;Shiyong Huang;Yu-Fei Sun;Luxiang Xu;Roysmond Zhen Wei Sim;Jen Siong Yee;Zhonglin Zhang;Igor Levchenko;Shuyan Xu;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Feb 2018, volume: 46, issue:2, pages: 338 - 344
Publisher: IEEE
 
» Prediction of the Leadership Style of an Emergent Leader Using Audio and Visual Nonverbal Features
Abstract:
The coordination of a leader with group members is very important for an effective leadership given that this figure is the person who actually manages the team members to achieve a desired goal. Investigating the leadership and especially the leadership style is a prominent research topic in social and organizational psychology. However this is a new problem in social signal processing that can actually make valuable contributions by analyzing multimodal data in a more effective and efficient way. In this work we identify the leadership style of an emergent leader (i.e. the leader who naturally arises from a group not designated) as autocratic or democratic. The proposed method is applied to a dataset in-the-wild; in other words there is no role-playing which is novel for this problem. Multiple kernel learning (MKL) using multimodal nonverbal features is utilized to predict leadership styles that proved to achieve better predictions as compared to traditional learning methods. Thanks to MKL and a simple heuristic proposed the best performing features are also identified showing that better predictions can be reached only by using those features. Additionally correlation analysis between the extracted nonverbal features and the results of social psychology questionnaire is also performed. This shows that significantly high correlations exist for speaking activity based and prosodic nonverbal features.
Autors: Cigdem Beyan;Francesca Capozzi;Cristina Becchio;Vittorio Murino;
Appeared in: IEEE Transactions on Multimedia
Publication date: Feb 2018, volume: 20, issue:2, pages: 441 - 456
Publisher: IEEE
 
» Predictive Brake Control for Electric Vehicles
Abstract:
This paper presents a predictive braking control algorithm for electric vehicles with redundant braking actuators, composed of friction brake actuator(s) and electric motor(s). The proposed algorithm is based on a model predictive control framework and is able to optimally tackle several control goals, such as maximization of energy recuperation and wheel slip regulation, while taking into account actuation dynamics and constraints. The braking control algorithm was simulated and experimentally validated on the ROMO research vehicle. The obtained results demonstrate that in comparison with state-of-the-art control techniques, the proposed model predictive control approach is able to reduce the torque tracking error up to 60%, and improve the deceleration during emergency braking up to 10%.
Autors: Clemens Satzger;Ricardo de Castro;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Feb 2018, volume: 67, issue:2, pages: 977 - 990
Publisher: IEEE
 
» Preparing to Witness a Multimegawatt Motor and Adjustable Speed Drive Acceptance Test–The Basics
Abstract:
Adjustable speed drive (ASD) and motors, if selected as a prime mover for compressors, pumps, extruders, etc., can provide various electromechanical benefits to its operators and stakeholders. Their benefits and application considerations have been well documented in past papers and tutorials. However, a successful installation of a multimegawatt motor and ASD system requires detailed application, engineering, manufacturing, testing, and installation considerations. Many times testing is requested by the operator and/or consultant, but navigating the types of tests available, test procedures, plans, and how they comply with appropriate standards is often not fully understood. This can lead to surprises, shipment delays, price adders, and ultimately the equipment itself not being in compliance with the stated project objectives. This paper attempts to address the factory acceptance testing phase of a medium voltage motor and ASD system whether procured separately or as a package. Issues such as type of test selection, specifications, standards, preparation, acceptance criteria, and finally string testing will be covered. This paper serves as a guideline of how one can select, prepare, witness, and sign off on a medium voltage motor and ASD test.
Autors: Manish Verma;Izhak (Ike) Grinbaum;John Arnold;James Nanney;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 873 - 882
Publisher: IEEE
 
» Pressure Pulse Distortion by Needle and Fiber-Optic Hydrophones due to Nonuniform Sensitivity
Abstract:
Needle and fiber-optic hydrophones have frequency-dependent sensitivity, which can result in substantial distortion of nonlinear or broadband pressure pulses. A rigid cylinder model for needle and fiber-optic hydrophones was used to predict this distortion. The model was compared with measurements of complex sensitivity for a fiber-optic hydrophone and three needle hydrophones with sensitive element sizes () of 100, 200, 400, and . Theoretical and experimental sensitivities agreed to within 12 ± 3% [root-mean-square (RMS) normalized magnitude ratio] and 8° ± 3° (RMS phase difference) for the four hydrophones over the range from 1 to 10 MHz. The model predicts that distortions in peak positive pressure can exceed 20% when and spectral index (SI) >7% and can exceed 40% when and SI >14%, where is the wavelength of the fundamental component and SI is the fraction of power spectral density contained in harmonics. The model predicts that distortions in peak negative pressure can exceed 15% when . Measurements of pulse distortion using a 2.25 MHz source and needle hydrophones with , 400, and <- nline-formula> $600~mu text{m}$ agreed with the model to within a few percent on the average for SI values up to 14%. This paper 1) identifies conditions for which needle and fiber-optic hydrophones produce substantial distortions in acoustic pressure pulse measurements and 2) offers a practical deconvolution method to suppress these distortions.
Autors: Keith A. Wear;Yunbo Liu;Gerald R. Harris;
Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Publication date: Feb 2018, volume: 65, issue:2, pages: 137 - 148
Publisher: IEEE
 
» Prestack Seismic Inversion Based on Anisotropic Markov Random Field
Abstract:
Prestack seismic inversion is an ill-posed problem and must be regularized to stabilize the inverted results. In particular, edge-preserving regularization with prior constraints based on Markov random field (MRF) has proved to be an effective technique for reconstructing subsurface models. However, regularized seismic inversion, based on the standard MRF scheme, typically makes use of isotropic MRF neighborhoods, in which the weighting coefficients of the model gradients are equivalent in all directions. Considering real geological conditions, subsurface formations are expected to be laterally continuous and vertically stratified. Therefore, the anisotropic effects caused by model gradients which vary along different directions should not be ignored. In this paper, we proposed a new prestack seismic inversion method based on anisotropic MRF (AMRF). In this method, AMRF coefficients are incorporated into the standard MRF scheme. These coefficients demonstrate directional variations and gradient dependencies, intended to directly correct the errors caused by the anisotropic model gradients on the prior constraints. In particular, we introduced the anisotropic diffusion method to calculate the AMRF coefficients. The proposed inversion method can effectively remove the anisotropic features of the model gradients and significantly improve the inversion results, especially for geologically layered formations. We demonstrated the effectiveness of the inversion method by both 2-D synthetic test and field data example, which presented encouraging results.
Autors: Qiang Guo;Hongbing Zhang;Feilong Han;Zuoping Shang;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2018, volume: 56, issue:2, pages: 1069 - 1079
Publisher: IEEE
 
» Pricing and Benefit of Decentralization for Competing Supply Chains With Fixed Costs
Abstract:
This paper develops two duopoly game models to explore price decisions and the channel benefit of decentralization for two supply chains, and investigates the channel structure decisions in the presence of fixed marketing and manufacturing costs. We give the price decisions and discuss price distortion. Under the downward decentralization model, our analysis reveals that first, symmetric decentralization improves supply chain profit only when the fixed marketing costs are high or product substitutability is high; second, decentralization improves channel profit, and symmetric decentralization (i.e., both manufacturers use decentralization) is an equilibrium if the fixed marketing (or unit production) costs are sufficiently high and the market scales are sufficiently small; and third, the presence of fixed marketing costs and asymmetry of supply chains support the existence of asymmetric equilibrium. Under the upward decentralization model, we find that symmetric outsourcing emerges when the fixed manufacturing cost or the unit production cost is low while both market scale and product substitutability are large in the supplier-led setting, the channel profit under downward decentralization is higher than that under symmetric outsourcing only if product substitutability is high, and the sourcing strategy largely depends on the specific game sequence.
Autors: Tiaojun Xiao;Tsan-Ming Choi;T. C. Edwin Cheng;
Appeared in: IEEE Transactions on Engineering Management
Publication date: Feb 2018, volume: 65, issue:1, pages: 99 - 112
Publisher: IEEE
 
» Private Information Retrieval from MDS Coded Data With Colluding Servers: Settling a Conjecture by Freij-Hollanti et al.
Abstract:
A instance of private information retrieval from MDS coded data with colluding servers (in short, MDS-TPIR), is comprised of messages and distributed servers. Each message is separately encoded through a MDS storage code. A user wishes to retrieve one message, as efficiently as possible, while revealing no information about the desired message index to any colluding set of up to servers. The fundamental limit on the efficiency of retrieval, i.e., the capacity of MDS-TPIR is known only at the extremes where either or belongs to . The focus of this work is a recent conjecture by Freij-Hollanti, Gnilke, Hollanti, and Karpuk which offers a general capacity expression for MDS-TPIR. We prove that the conjecture is false by presenting as a counterexample a PIR scheme for the setting , which achieves the rate 3/5, exceeding the conjectured capacity, 4/7. Insights from the counterexample lead us to capacity characterizations for various instances of MDS-TPIR, including all cases with , where and $T$ can be arbitrary.
Autors: Hua Sun;Syed Ali Jafar;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 1000 - 1022
Publisher: IEEE
 
» Probabilistic Context-Aware Step Length Estimation for Pedestrian Dead Reckoning
Abstract:
This paper introduces a weighted context-based step length estimation algorithm for pedestrian dead reckoning. Six pedestrian contexts are considered: stationary, walking, walking sideways, climbing and descending stairs, and running. Instead of computing the step length based on a single context, the step lengths computed for different contexts are weighted by the context probabilities. This provides more robust performance when the context is uncertain. The proposed step length estimation algorithm is part of a pedestrian dead reckoning system which includes the procedures of step detection and context classification. The step detection algorithm detects the step time boundaries using continuous wavelet transform analysis, while the context classification algorithm determines the pedestrian context probabilities using a relevance vector machine. In order to assess the performance of the pedestrian dead reckoning system, a data set of pedestrian activities and actions has been collected. Fifteen subjects have been equipped with a waist-belt smartphone and traveled along a predefined path. Acceleration, angular rate and magnetic field data were recorded. The results show that the traveled distance is more accurate using step lengths weighted by the context probabilities compared to using step lengths based on the highest probability context.
Autors: Alessio Martinelli;Han Gao;Paul D. Groves;Simone Morosi;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1600 - 1611
Publisher: IEEE
 
» Probabilistic Estimation of Distribution Network Performance With Respect to Voltage Sags and Interruptions Considering Network Protection Setting—Part I: The Methodology
Abstract:
Nowadays, modern industrial processes are controlled by equipment highly sensitive to voltage sags and interruptions. Although the proposed methods in the literature allow utilities to estimate annual equipment trips due to voltage sags and permanent interruptions, they do not assess explicitly momentary interruptions. This paper proposes a probabilistic methodology that includes the attempts of reclosers to clear nonpermanent faults during the estimation of annual voltage sags and momentary interruptions at each busbar. Furthermore, voltage-tolerance ranges for each type of equipment are taken into account to quantify annual equipment trips due to voltage sags and momentary interruptions for each customer in the distribution network. The results allow the utility to identify a geographic area where sets of customers face high equipment trips during the year. The proposed methodology can be used by utilities to prioritize corrective measures to improve the quality of service to those customers most affected by annual equipment trips.
Autors: Juan Carlos Cebrian;Nelson Kagan;Jovica V. Milanović;
Appeared in: IEEE Transactions on Power Delivery
Publication date: Feb 2018, volume: 33, issue:1, pages: 42 - 51
Publisher: IEEE
 
» Probabilistic Threat Detection for Risk Management in Cyber-physical Medical Systems
Abstract:
Medical devices are complex cyber-physical systems incorporating emergent hardware and software components. However, this complexity leads to a wide attack surface posing security risks and vulnerabilities. Mitigation and management of such risks during premarket design and postmarket deployment are required. Dynamically mitigating threat potential in the presence of unknown vulnerabilities requires an adaptive risk-based scheme to assess the system’s state, a secure system architecture that can isolate hardware and software components, and design methods that can adaptively adjust the system’s topology based on risk changes. The essential complementary aspects during deployment are detecting, characterizing, and quantifying security threats. This article presents a dynamic risk management and mitigation approach based on probabilistic threat estimation. A smart-connected-pacemaker case study illustrates the approach. This article is part of a special issue on Software Safety and Security Risk Mitigation in Cyber-physical Systems.
Autors: Aakarsh Rao;Nadir Carreón;Roman Lysecky;Jerzy Rozenblit;
Appeared in: IEEE Software
Publication date: Feb 2018, volume: 35, issue:1, pages: 38 - 43
Publisher: IEEE
 
» Probability-Based Depth Intra-Mode Skipping Strategy and Novel VSO Metric for DMM Decision in 3D-HEVC
Abstract:
Multiview video plus depth format has been adopted as the emerging 3D video representation recently. It includes a limited number of textures and depth maps to synthesize additional virtual views. Since the quality of depth maps influences the view synthesis process, their sharp edges should be well preserved to avoid mixing foreground with background. To address this issue, 3D-High Efficiency Video Coding (HEVC) introduces new coding tools, a partition-based intra mode [depth modeling mode (DMM)], a residual description technique [segmentwise depth coding (SDC)], and a more complex rate-distortion (RD) evaluation with view synthesis optimization (VSO), to provide more accurate predictions and achieve higher compression rate. However, these new techniques introduce a lot of possible candidates, and each of them requires complicated RD calculation in the process of intra-mode decision. They lead to unacceptable computational burden in a 3D-HEVC encoder. Therefore, in this paper, we raise two efficient techniques for depth intra-mode decision. First, by investigating the statistical characteristics of variance distributions in the two partitions of DMM, a simple but efficient criterion based on the squared Euclidean distance of variances (SEDV) is suggested to evaluate RD costs of the DMM candidates instead of the time-consuming VSO process. Second, a probability-based early depth intra-mode decision is proposed to select only the most promising mode and make the early determination of using SDC based on the low-complexity RD cost in rough mode decision. Experimental results show that the proposed algorithm with these two new techniques provides 33%–48% time reduction with little drop in the coding performance compared with the state-of-the-art algorithms.
Autors: Hong-Bin Zhang;Chang-Hong Fu;Yui-Lam Chan;Sik-Ho Tsang;Wan-Chi Siu;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Feb 2018, volume: 28, issue:2, pages: 513 - 527
Publisher: IEEE
 
» Processing of Long Integration Time Spaceborne SAR Data With Curved Orbit
Abstract:
Long integration time (LIT) indicates high resolution and/or large scene for spaceborne synthetic aperture radar (SAR) imaging and also means that the effects, brought by curved orbit, cannot be ignored. In this paper, considering the curved orbit caused by the relative motion between an SAR sensor in orbit and targets on a rotating planetary surface, the impacts of the LIT on the imaging results are discussed in detail. The analysis suggests that the cross-coupling phase is two-dimensional (2-D) with spatial variation. Employing the 2-D Taylor series expansion, the 2-D linear relationships between the spatially variant and invariant coefficients are derived, which are exploited to improve the echo formulation. Then, we apply the keystone transform (KT) to process the LIT spaceborne SAR data. Unlike the traditional application of the KT, our two proposed methods, which operate, respectively, in azimuth time and azimuth frequency domains, can greatly remove the spatially variant cross-coupling phase. Moreover, implementation considerations including the curved orbit of LIT spaceborne SAR, applicability of two methods, postprocessing for topography error compensation, and computational load are discussed. Simulation results verify the effectiveness of the developed focusing approaches.
Autors: Shiyang Tang;Chunhui Lin;Yu Zhou;Hing Cheung So;Linrang Zhang;Zheng Liu;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2018, volume: 56, issue:2, pages: 888 - 904
Publisher: IEEE
 
» Product Adoption Rate Prediction in a Competitive Market
Abstract:
As the worlds of commerce and the Internet technology become more inextricably linked, a large number of user consumption series become available for online market intelligence analysis. A critical demand along this line is to predict the future product adoption state of each user, which enables a wide range of applications such as targeted marketing. Nevertheless, previous works only aimed at predicting if a user would adopt a particular product or not with a binary buy-or-not representation. The problem of tracking and predicting users’ adoption rates, i.e., the frequency and regularity of using each product over time, is still under-explored. To this end, we present a comprehensive study of product adoption rate prediction in a competitive market. This task is nontrivial as there are three major challenges in modeling users’ complex adoption states: the heterogeneous data sources around users, the unique user preference and the competitive product selection. To deal with these challenges, we first introduce a flexible factor-based decision function to capture the change of users’ product adoption rate over time, where various factors that may influence users’ decisions from heterogeneous data sources can be leveraged. Using this factor-based decision function, we then provide two corresponding models to learn the parameters of the decision function with both generalized and personalized assumptions of users’ preferences. We further study how to leverage the competition among different products and simultaneously learn product competition and users’ preferences with both generalized and personalized assumptions. Finally, extensive experiments on two real-world datasets show the superiority of our proposed models.
Autors: Le Wu;Qi Liu;Richang Hong;Enhong Chen;Yong Ge;Xing Xie;Meng Wang;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Feb 2018, volume: 30, issue:2, pages: 325 - 338
Publisher: IEEE
 
» Production Control to Reduce Starvation in a Partially Flexible Production-Inventory System
Abstract:
In this paper, we study production control problems in a partially flexible production-inventory system. In such a system, the upstream flexible production subsystem can make two different products, with nonnegligible setup time during changeover. The downstream inflexible production subsystem consists of two manufacturing facilities, with each dedicated to one product type only. The two production subsystems are connected by two dedicated buffers, which comprise the inventory subsystem. Using a renewal model, an optimal control policy is developed to switch products by predefined thresholds for inventory levels to minimize starvation (idle) time of downstream productions. Closed formulas are derived, and sensitivity analyses with respect to setup time change, machine reliability variation, and demand fluctuation are carried out. Finally, an application study in a door manufacturing line at an automotive assembly plant making two distinct types of doors is introduced.
Autors: Cong Zhao;Ningxuan Kang;Jingshan Li;John A. Horst;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Feb 2018, volume: 63, issue:2, pages: 477 - 491
Publisher: IEEE
 
» Propagation of AC Background Harmonics in MMC HVdc Multiterminal Systems Due to Resonances and Mitigation Measures
Abstract:
Modular multilevel converter (MMC)-based multiterminal HVdc (MTdc) transmission is a favorable option for asynchronously interconnecting several weak ac systems. This paper investigates the potential resonance of such an MMC-MTdc system excited by background harmonics in any of the MMC's ac systems and the undesirable transfer of these harmonics to the remote ac systems. First, the harmonic transfer rule across one MMC is established using phase leg voltage analysis and it is then used to develop an equivalent circuit model of the MMC-MTdc system. This model is used to investigate the mechanism of resonance excited by ac-side background harmonics. Finally, a control strategy is proposed to mitigate this resonance. Analytically calculated results from the derived model and the proposed control strategy are validated via electromagnetic transients simulation of a five-terminal MMC-MTdc network.
Autors: Dong Xu;Minxiao Han;Aniruddha M. Gole;
Appeared in: IEEE Transactions on Power Delivery
Publication date: Feb 2018, volume: 33, issue:1, pages: 229 - 238
Publisher: IEEE
 
» Prospects and Limitations of Power Balance Approach for Studying Forces and Electromagnetic Damping in Electrical Machines
Abstract:
A cage induction machine with dynamic rotor eccentricity is considered. In general, force and torque computations in the finite-element analysis of electrical machines are done using conventional direct methods. Many methods have been put forward with a claim to be more accurate than one another. In this paper, we assess the accuracy of the typical force computation method used in the finite-element analysis of electrical machines, for various types of mesh used in the machine’s air gap during simulations. The possibility of using the power balance of the machine to validate the force calculation and alternatively calculate the force is discussed. Besides, its applicability to study the electromagnetic damping of mechanical vibrations due to unbalanced magnetic pull is presented.
Autors: Bishal Silwal;Paavo Rasilo;Antero Arkkio;
Appeared in: IEEE Transactions on Magnetics
Publication date: Feb 2018, volume: 54, issue:2, pages: 1 - 8
Publisher: IEEE
 
» Provably Good Max–Min- $m$ -Neighbor-TSP-Based Subfield Scheduling for Electron-Beam Photomask Fabrication
Abstract:
Electron beam lithography (EBL) has been used for high-resolution photomask fabrication; its successive heating process in a certain region, however, may cause critical dimension (CD) distortion. As a result, subfield scheduling, which reorders a sequence of subfields in the writing process, is desirable to avoid the heating problem and thus CD distortion. To consider longer range heat dissipation, this paper models a subfield scheduling problem with blocked region consideration as a constrained max–min -neighbor traveling salesman problem (called constrained -nTSP). To solve the constrained -nTSP which is NP-complete in general, we decompose a constrained -nTSP into subproblems conforming to a special case with points on two parallel lines, solve each of them with a provably good linear-time approximation algorithm, and merge them into a complete scheduling solution. In particular, our algorithm can also minimize the distances between successive subfields to alleviate the throughput degradation of EBL writing due to moving a writing head, while minimizing the heating problem. Average reductions of 10% in the maximum temperature and 14% in the distances between successive subfields over the state-of-the-art work can be achieved.
Autors: Zhi-Wen Lin;Shao-Yun Fang;Yao-Wen Chang;Wei-Cheng Rao;Chieh-Hsiung Kuan;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Feb 2018, volume: 26, issue:2, pages: 378 - 391
Publisher: IEEE
 
» PROVEST: Provenance-Based Trust Model for Delay Tolerant Networks
Abstract:
Delay tolerant networks (DTNs) are often encountered in military network environments where end-to-end connectivity is not guaranteed due to frequent disconnection or delay. This work proposes a provenance-based trust framework, namely PROVEST (PROVEnance-baSed Trust model) that aims to achieve accurate peer-to-peer trust assessment and maximize the delivery of correct messages received by destination nodes while minimizing message delay and communication cost under resource-constrained network environments. Provenance refers to the history of ownership of a valued object or information. We leverage the interdependency between trustworthiness of information source and information itself in PROVEST. PROVEST takes a data-driven approach to reduce resource consumption in the presence of selfish or malicious nodes while estimating a node's trust dynamically in response to changes in the environmental and node conditions. This work adopts a model-based method to evaluate the performance of PROVEST (i.e., trust accuracy and routing performance) using Stochastic Petri Nets. We conduct a comparative performance analysis of PROVEST against existing trust-based and non-trust-based DTN routing protocols to analyze the benefits of PROVEST. We validate PROVEST using a real dataset of DTN mobility traces.
Autors: Jin-Hee Cho;Ing-Ray Chen;
Appeared in: IEEE Transactions on Dependable and Secure Computing
Publication date: Feb 2018, volume: 15, issue:1, pages: 151 - 165
Publisher: IEEE
 
» Proximity Operators of Discrete Information Divergences
Abstract:
While -divergences have been extensively studied in convex analysis, their use in optimization problems often remains challenging. In this regard, one of the main shortcomings of existing methods is that the minimization of -divergences is usually performed with respect to one of their arguments, possibly within alternating optimization techniques. In this paper, we overcome this limitation by deriving new closed-form expressions for the proximity operator of such two-variable functions. This makes it possible to employ standard proximal methods for efficiently solving a wide range of convex optimization problems involving -divergences. In addition, we show that these proximity operators are useful to compute the epigraphical projection of several functions. The proposed proximal tools are numerically validated in the context of optimal query execution within database management systems, where the problem of selectivity estimation plays a central role. Experiments are carried out on small to large scale scenarios.
Autors: Mireille El Gheche;Giovanni Chierchia;Jean-Christophe Pesquet;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 1092 - 1104
Publisher: IEEE
 
» PSOSAC: Particle Swarm Optimization Sample Consensus Algorithm for Remote Sensing Image Registration
Abstract:
Image registration is an important preprocessing step for many remote sensing image processing applications, and its result will affect the performance of the follow-up procedures. Establishing reliable matches is a key issue in point matching-based image registration. Due to the significant intensity mapping difference between remote sensing images, it may be difficult to find enough correct matches from the tentative matches. In this letter, particle swarm optimization (PSO) sample consensus algorithm is proposed for remote sensing image registration. Different from random sample consensus (RANSAC) algorithm, the proposed method directly samples the modal transformation parameter rather than randomly selecting tentative matches. Thus, the proposed method is less sensitive to the correct rate than RANSAC, and it has the ability to handle lower correct rate and more matches. Meanwhile, PSO is utilized to optimize parameter as its efficiency. The proposed method is tested on several multisensor remote sensing image pairs. The experimental results indicate that the proposed method yields a better registration performance in terms of both the number of correct matches and aligning accuracy.
Autors: Yue Wu;Qiguang Miao;Wenping Ma;Maoguo Gong;Shanfeng Wang;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Feb 2018, volume: 15, issue:2, pages: 242 - 246
Publisher: IEEE
 
» PUF-Assisted Group Key Distribution Scheme for Software-Defined Wireless Sensor Networks
Abstract:
In this letter, a novel group key distribution scheme based on physical unclonable functions (PUFs) is proposed for software-defined wireless sensor networks. The PUF is difficult to be cloned and predicted, remarkably enhancing physical security performance of sensor nodes. In addition, under the centralized management of software-defined networking, PUF challenge is stored in the sensor nodes to minimize communication overhead. The proposed algorithm achieves group key delivery with two-way authentication function through one communication interaction. We demonstrate the scheme can resist multiple attacks, including cloning, eavesdropping, and so on, thus effectively guaranteeing the security and efficiency of group key distribution process.
Autors: Meigen Huang;Bin Yu;Sensen Li;
Appeared in: IEEE Communications Letters
Publication date: Feb 2018, volume: 22, issue:2, pages: 404 - 407
Publisher: IEEE
 
» Pure Photosynthates Extraction Sensor Device With Highly Precise Phloem/Xylem Position Identification
Abstract:
We propose a pure photosynthates extraction sensor device integrated with highly precise phloem/xylem position identification to quantitatively monitor the components of internal higher plants, which is a key indicator for controlling stable crop production. The essential functions of the device are high-precisely identifying phloem/xylem positions based on electrical conductivity and extracting pure phloem sap. We fabricated the proposed device with microelectromechanical systems technology and evaluated its effectiveness. It is confirmed that the performance of our fabricated electrical conductivity sensor is almost equal to that of a commercially available meter. (The error of these characteristic lines is less than 5%.) Experiments with cucumber stems confirmed that the device can precisely measure the electrical conductivity of phloem/xylem sap in the appropriate range of internal plants or soil (0.0–1.0 mS/cm), identifying their positions stably over a long period. Extraction experiments demonstrated that phloem sap from the internal plant flows readily into the extraction flow channel and a reservoir. Therefore, we clearly demonstrated the feasibility of a novel sensor device that can conveniently identify the phloem positions and extract pure photosynthates samples in agricultural situations.
Autors: Akihito Ono;Akihito Yoneda;Hiroki Ishizuka;Kyohei Terao;Hidekuni Takao;Naoshi Takahashi;Tsuyoshi Kobayashi;Ikuo Kataoka;Fusao Shimokawa;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1739 - 1746
Publisher: IEEE
 
» Q-Switched Dual-Wavelength Laser at 1116 and 1123 nm Using WS2 Saturable Absorber
Abstract:
Longitudinally diode-pumped continuous-wave dual-wavelength Nd:YAG laser at 1116 and 1123 nm is achieved with maximum output power of 8.18 W and slope efficiency of 42.3%. Using WS2 as saturable absorber, passive Q-switching of the dual-wavelength laser is also achieved with a maximum average output power of 0.41 W, the shortest pulse width of about at pulse repetition rate of 100.9 kHz. The present Q-switched laser operation leads to maximum pulse energy of and pulse peak power of 6.35 W. A 2-D material WS2 has been experimentally confirmed to be very promising as Q switcher at , for the first time to our knowledge.
Autors: Haifeng Lin;Wenzhang Zhu;Ruizhen Mu;Hongyi Zhang;Feibing Xiong;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:3, pages: 285 - 288
Publisher: IEEE
 
» Quantification of Ethanol Concentration in Gasoline Using Cuprous Oxide Coated Long Period Fiber Gratings
Abstract:
It is reported a new optical sensing system, based on long period fiber gratings (LPFGs) coated with cuprous oxide (Cu2O), for the quantification of ethanol concentration in ethanol-gasoline mixtures. The detection principle is based on the spectral features dependence of the Cu2O coated LPFGs on the refractive index of the surrounding medium. The chemical constitution of the ethanol-gasoline samples was obtained by gas chromatography mass spectrometry (GC) and GC thermal conductivity detection. Two different modes of operation are presented, wavelength shift and optical power shift mode of operation, with good linear relations between ethanol concentration and the corresponding spectral features of the LPFGs, and 0.996, respectively. In the range of ethanol concentration up to 30% v/v, the sensitivities were 0.76 ± 0.01 nm/% v/v and 0.125 ± 0.003 dB/% v/v with resolutions of 0.21% v/v and 0.73% v/v and limits of detection of 1.63% v/v and 2.10% v/v, for the for the same operation modes, respectively.
Autors: Filipe Monteiro-Silva;José Luís Santos;José Manuel Marques Martins de Almeida;Luis Coelho;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1493 - 1500
Publisher: IEEE
 
» Quantification of the Relationship Between Sea Surface Roughness and the Size of the Glistening Zone for GNSS-R
Abstract:
A formulation of the relationship between sea-surface roughness and extension of the glistening zone (GZ) of a Global Navigation Satellite System Reflectometry (GNSS-R) system is presented. First, an analytical expression of the link between GZ area, viewing geometry, and surface mean square slope (MSS) is derived. Then, a strategy for retrieval of surface roughness from the delay-Doppler map (DDM) is illustrated, including details of data preprocessing, quality control, and GZ area estimation from the DDM. Next, an example for application of the proposed approach to spaceborne GNSS-R remote sensing is provided, using DDMs from the TechDemoSat-1 mission. The algorithm is first calibrated using collocated in situ roughness estimates using data sets from the National Data Buoy Center, its retrieval performance is then assessed, and some of the limitations of the suggested technique are discussed. Overall, good correlation is found between buoy-derived MSS and estimates obtained using the proposed strategy ().
Autors: Qingyun Yan;Weimin Huang;Giuseppe Foti;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Feb 2018, volume: 15, issue:2, pages: 237 - 241
Publisher: IEEE
 
» Quantifying the Impact of Random Surface Perturbations on Reflective Gratings
Abstract:
We present a novel deterministic method capable of calculating statistical moments of transverse electric polarized fields scattered by perfect electric conductor gratings with small surface random perturbations. Based on a first-order shape Taylor expansion, the resulting electric field integral equations are solved via the method of moments with constant hierarchical basis or Haar wavelets. This allows for a sparse tensor approximation, significantly reducing the number of required unknowns and yielding a higher rate of convergence than a dense approximation. Moreover, the proposed approach converges faster than Monte Carlo simulations with significantly less computational effort. Validation of the proposed approach is performed for several cases, and realistic simulations applied to the calculation and prediction of grating efficiency reveal the applicability of the method.
Autors: Gerardo Silva-Oelker;Rubén Aylwin;Carlos Jerez-Hanckes;Patrick Fay;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2018, volume: 66, issue:2, pages: 838 - 847
Publisher: IEEE
 
» Quantitative Analysis of Magnetic Field Distribution Around Circular Non-Magnetic Region in Grain-Oriented Fe-3%Si Steel
Abstract:
The detrimental effects of drilling electrical steel sheets on the flux propagation and domain structure in the vicinity of a hole were experimentally studied by using Kerr microscopy. As a model system, a (110)[001]-textured Fe-3%Si sheet sample in Epstein geometry with the preferred transverse and longitudinal axis to the working direction and a 10 mm hole in the middle of the sheet sample were chosen. Under such conditions, branched surface domains are formed in moderate magnetic fields, the orientation of which turned out to be a sensitive indicator for the local effective field, thus allowing to visualize the flux propagation and degradation around the hole. It was also found an interesting way to use the orientation of the surface domains at the presence of an applied magnetic field as an indicator for the local effective field direction. Since the reluctance was growth depending upon decreasing cross-sectional area in the sides of the non-magnetic region, rapid saturation was able to observe by the evaluation of magnetic domains.
Autors: T. Gunes;R. Schäfer;N. Derebasi;
Appeared in: IEEE Transactions on Magnetics
Publication date: Feb 2018, volume: 54, issue:2, pages: 1 - 8
Publisher: IEEE
 
» Quantum-Cascade Vertical-Cavity Surface-Emitting Laser
Abstract:
This letter shows the possibility of stimulated emission in quantum cascades (QCs) embedded in a vertical cavity and proposes a first design for the QC vertical-cavity surface-emitting laser (QC VCSEL). In the proposed design, the top VCSEL mirror is a monolithic high-refractive-index contrast grating, which serves as both an optical coupler and as the region in which the vertical component of the electrical field is induced, enabling stimulating emission from the QCs. Using a three-dimensional, fully vectorial optical model combined with an electrical model and gain model, the distribution of the optical field, threshold current, emitted optical power, and wall-plug efficiency of a 9 AlInAs/InGaAs/InP QC VCSEL are simulated.
Autors: Tomasz Czyszanowski;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:4, pages: 351 - 354
Publisher: IEEE
 
» Quasi-Distributed Optical Fiber Transducer for Simultaneous Temperature and Vibration Sensing in High-Power Generators
Abstract:
In this paper, a new multiparametric optical fiber transducer is presented for simultaneous temperature and vibration sensing in hydroelectric high-power generators. The optical transducer holds three multiplexed fiber Bragg gratings (FBGs) as the sensing elements. In the transducer, each FBG can simultaneously measure temperature and vibration independent of the other FBGs. With a temperature characterization, it is possible to determine the thermal stability (1.5 °C) over the test duration and the thermal sensitivity of the packaged FBGs 10 pm/°C. Moreover, the vibration characterization tests rely on an impact hammer and a shaker. With the impact hammer test, the transducer package natural frequency of 565 Hz is determined. The shaker performed a frequency sweep over 5 Hz to 1 kHz, and the transducer mean vibration sensitivity is found to be 7.2 pm/g. Subsequently, the power plant installation is performed using six transducers. They are installed into six different windings slots to sense stator bars of a 370-MVA hydroelectric generator. With this instrumentation, 23 h of simultaneous vibration and temperature sensing is carried out. All the FBGs used to monitor vibration were able to monitor the frequency of mechanical vibration (2 Hz) and electromagnetic vibration (120 Hz) of the generator. During the power plant test, the machine was turned OFF due to a failure and all the FBGs were able to measure the temperature as well as vibration changes caused by the machine shutdown.
Autors: Uilian José Dreyer;Felipe Mezzadri;Guilherme Dutra;Thiago da Silva;Carlos Alberto Bavastri;Erlon Vagner da Silva;Cicero Martelli;Jean Carlos Cardozo da Silva;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1547 - 1554
Publisher: IEEE
 
» Quasi-Random Single-Point Imaging Using Low-Discrepancy $k$ -Space Sampling
Abstract:
Magnetic resonance imaging of short relaxation time spin systems has been a widely discussed topic with serious clinical applications and led to the emergence of fast imaging ultra-short echo-time sequences. Nevertheless, these sequences suffer from image blurring, due to the related sampling point spread function and are highly prone to imaging artefacts arising from, e.g., chemical shifts or magnetic susceptibilities. In this paper, we present a concept of spherical quasi-random single-point imaging. The approach is highly accelerateable, due to intrinsic undersampling properties and capable of strong metal artefact suppression. Imaging acceleration is achieved by sampling of quasi-random points in -space, based on a low-discrepancy sequence, and a combination with non-linear optimization reconstruction techniques [compressed sensing (CS)]. The presented low-discrepancy trajectory shows ideal noise like undersampling properties for the combination with CS, leading to denoised images with excellent metal artefact reduction. Using eightfold undersampling, acquisition time of a few minutes can be achieved for volume acquisitions.
Autors: Tobias Speidel;Jan Paul;Stefan Wundrak;Volker Rasche;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Feb 2018, volume: 37, issue:2, pages: 473 - 479
Publisher: IEEE
 
» Radar Propagation Experiment in the North Sea: The Sylt Campaign
Abstract:
This paper describes an experiment that was carried out in the North Sea off the Sylt island in May 2012 with the aim to study the influence of the maritime boundary layer conditions on the propagation of radar signals under low grazing angle geometry and to establish a sea clutter database at different frequencies with a view to contribute to new sea clutter models. The radar measurements were carried out with the highly versatile radar called MEMPHIS operating in sea configuration at X-, Ka-, and W-band, simultaneously. As concerns the oceanographic and atmospheric characterization, the collection of measurements was done with a sophisticated suite of sensors partly mounted on the research vessel (RV) Elisabeth Mann Borgese (EMB) and onboard different types of buoys, a catamaran, and a tethered balloon. Over a period of four days, a comprehensive and valuable data set was successfully collected including clutter measurements under different geometrical configurations and propagation runs with corner reflectors mounted onboard RV EMB. An insight into the overall approach is given together with many measurement examples for a very detailed oceanographic and meteorological characterization and a vast number of multifrequency radar acquisitions, showing the complexity of different parameters that have to be considered for sensor performance assessment and prediction.
Autors: Andreas Danklmayer;Jörg Förster;Vincent Fabbro;Gregor Biegel;Thorsten Brehm;Paul Colditz;Laurent Castanet;Yvonick Hurtaud;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2018, volume: 56, issue:2, pages: 835 - 846
Publisher: IEEE
 
» RAFP-Pred: Robust Prediction of Antifreeze Proteins Using Localized Analysis of n-Peptide Compositions
Abstract:
In extreme cold weather, living organisms produce Antifreeze Proteins (AFPs) to counter the otherwise lethal intracellular formation of ice. Structures and sequences of various AFPs exhibit a high degree of heterogeneity, consequently the prediction of the AFPs is considered to be a challenging task. In this research, we propose to handle this arduous manifold learning task using the notion of localized processing. In particular, an AFP sequence is segmented into two sub-segments each of which is analyzed for amino acid and di-peptide compositions. We propose to use only the most significant features using the concept of information gain (IG) followed by a random forest classification approach. The proposed RAFP-Pred achieved an excellent performance on a number of standard datasets. We report a high Youden’s index (sensitivity+specificity-1) value of 0.75 on the standard independent test data set outperforming the AFP-PseAAC, AFP_PSSM, AFP-Pred, and iAFP by a margin of 0.05, 0.06, 0.14, and 0.68, respectively. The verification rate on the UniProKB dataset is found to be 83.19 percent which is substantially superior to the 57.18 percent reported for the iAFP method.
Autors: Shujaat Khan;Imran Naseem;Roberto Togneri;Mohammed Bennamoun;
Appeared in: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Publication date: Feb 2018, volume: 15, issue:1, pages: 244 - 250
Publisher: IEEE
 
» Random Sets of Stadiums in Square and Collective Behavior of Bacteria
Abstract:
Collective motion of swimmers can be detected by hydrodynamic interactions through the effective (macroscopic) viscosity. It follows from the general hydrodynamics that the effective viscosity of non-dilute random suspensions depends on the shape of particles and of their spacial probabilistic distribution. Therefore, a comparative analysis of disordered and collectively interacting particles of the bacteria shape can be done in terms of the probabilistic geometric parameters which determine the effective viscosity. In this paper, we develop a quantitative criterion to detect the collective behavior of bacteria. This criterion is based on the basic statistic moments (-sums or generalized Eisenstein-Rayleigh sums) which characterize the high-order correlation functions. The locations and the shape of bacteria are modeled by stadiums randomly embedded in medium without overlapping. These shape models can be considered as improvement of the previous segment model. We calculate the -sums of the simulated disordered sets and of the observed experimental locations of bacteria subtilis. The obtained results show a difference between these two sets that demonstrates the collective motion of bacteria.
Autors: Roman Czapla;
Appeared in: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Publication date: Feb 2018, volume: 15, issue:1, pages: 251 - 256
Publisher: IEEE
 
» Rate Adaptation, Scheduling, and Mode Selection in D2D Systems With Partial Channel Knowledge
Abstract:
Device-to-device (D2D) communication enables simultaneous data transmissions by cellular users (CU) and D2D user pairs, but at the expense of additional interference between them. The literature on resource allocation in D2D systems often assumes that the base station (BS) has complete channel state information (CSI) about all the links between all the users in a cell. However, acquiring the CSI of cross links between the CUs and the D2D receivers is a critical bottleneck because the number of cross links is the product of the number of CUs and D2D pairs. We study a novel partial CSI model in which the overhead of feeding back the CSI of the cross links is much lower. For a cell with one D2D pair and multiple CUs, we propose a novel throughput-optimal joint mode selection, user scheduling, and rate adaptation policy that exploits information about the statistics of the cross links and incorporates inter-cell interference. We derive closed-form expressions for the feedback-conditioned goodput for the underlay mode, which drives this optimal policy. We also present extensions that incorporate user fairness, quantized CSI, and multiple D2D pairs and multiple subchannels.
Autors: Saikiran Bulusu;Neelesh B. Mehta;Suresh Kalyanasundaram;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Feb 2018, volume: 17, issue:2, pages: 1053 - 1065
Publisher: IEEE
 
» Real-Time Area Coverage and Target Localization Using Receding-Horizon Ergodic Exploration
Abstract:
Although a number of solutions exist for the problems of coverage, search, and target localization—commonly addressed separately—whether there exists a unified strategy that addresses these objectives in a coherent manner without being application specific remains a largely open research question. In this paper, we develop a receding-horizon ergodic control approach, based on hybrid systems theory, that has the potential to fill this gap. The nonlinear model-predictive control algorithm plans real-time motions that optimally improve ergodicity with respect to a distribution defined by the expected information density across the sensing domain. We establish a theoretical framework for global stability guarantees with respect to a distribution. Moreover, the approach is distributable across multiple agents so that each agent can independently compute its own control while sharing statistics of its coverage across a communication network. We demonstrate the method in both simulation and in experiment in the context of target localization, illustrating that the algorithm is independent of the number of targets being tracked and can be run in real time on computationally limited hardware platforms.
Autors: Anastasia Mavrommati;Emmanouil Tzorakoleftherakis;Ian Abraham;Todd D. Murphey;
Appeared in: IEEE Transactions on Robotics
Publication date: Feb 2018, volume: 34, issue:1, pages: 62 - 80
Publisher: IEEE
 
» Real-Time Blood Velocity Vector Measurement Over a 2-D Region
Abstract:
Quantitative blood velocity measurements, as currently implemented in commercial ultrasound scanners, are based on pulsed-wave (PW) spectral Doppler and are limited to detect the axial component of the velocity in a single sample volume. On the other hand, vector Doppler methods produce angle-independent estimates by, e.g., combining the frequency shifts measured from different directions. Moreover, thanks to the transmission of plane waves, the investigation of a 2-D region is possible with high temporal resolution, but, unfortunately, the clinical use of these methods is hampered by the massive calculation power required for their real-time execution. In this paper, we present a novel approach based on the transmission of plane waves and the simultaneous reception of echoes from 16 distinct subapertures of a linear array probe, which produces eight lines distributed over a 2-D region. The method was implemented on the ULAO-OP 256 research scanner and tested both in phantom and in vivo. A continuous real-time refresh rate of 36 Hz was achieved in duplex combination with a standard B-mode at pulse repetition frequency of 8 kHz. Accuracies of −11% on velocity and of 2°on angle measurements have been obtained in phantom experiments. Accompanying movies show how the method improves the quantitative measurements of blood velocities and details the flow configurations in the carotid artery of a volunteer.
Autors: Stefano Ricci;Alessandro Ramalli;Luca Bassi;Enrico Boni;Piero Tortoli;
Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Publication date: Feb 2018, volume: 65, issue:2, pages: 201 - 209
Publisher: IEEE
 
» Real-Time Electrical Characteristics of Microprobe Testing Process in Microelectronics Packaging
Abstract:
In order to investigate the electrical characteristics of microprobe in integrated circuit testing, a wafer probe admittance testing system with motion control and admittance measurement instruments was organized by using pogo microprobe whose impedance characteristics are automatically measured and analyzed. The probe’s admittance characteristics under different loading frequency were explored based on voltammetry. The results show that the probe was resistive when loading frequency was less than 100 kHz, and being inductive when the frequency was larger than 100 kHz. Furthermore, the probe’s admittance was the least when the frequency was between 200 and 400 kHz. Meanwhile, the conductivity of tipped needle is smaller than claw pin when the frequency is between 1 and 500 kHz, whereas the susceptance and resistance of tipped needle is larger than claw pin, which mainly due to the change of contact between probe and the solder.
Autors: Qing Tian;Qing Yuan;Xiaohui Wei;Junhui Li;
Appeared in: IEEE Transactions on Semiconductor Manufacturing
Publication date: Feb 2018, volume: 31, issue:1, pages: 166 - 172
Publisher: IEEE
 
» Real-Time Electro-Optical Tunable Hyperlens Under Subwavelength Scale
Abstract:
Hyperlens consisted by period plasmonic metamaterials is an interesting technology for the optical imaging of arbitrary objects beyond the diffraction limit in the far field, which has great potential applications in nanophotonics. However, the functionality of previously presented hyperlens is limited to image two-dimensional (2-D) objects and work at a certain wavelength due to the dispersion of metal, dramatically impose restrictions on its practical application. In this paper, we proposed and theoretically demonstrated a multiwavelength tunable hyperlens, with the ability of 3-D imaging by focal plane tuning achieved by electro-optical modulation. The simulation results indicate that full-width half-maximum (FWHM) of minimum imaging spot can be reduced down to the level of less than half-wavelength of the incident in a wide wavelength range real-timely, down to the level of ∼200 nm using visible light illumination. In addition, the focal position of the hyperlens can also be tuned in large spatial scope, which greatly facilitates the application of the hyperlens in optical signal acquisition and processing.
Autors: Dan Su;Xiao-Yang Zhang;Yuan-Liang Ma;Feng Shan;Jing-Yuan Wu;Xing-Chang Fu;Li-Jiang Zhang;Ke-Qiang Yuan;Tong Zhang;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 9
Publisher: IEEE
 
» Real-Time Impedance Characterization Method for RFID-Type Backscatter Communication Devices
Abstract:
This paper presents a radio frequency (RF) measurement method that allows to determine electrical characteristics such as scattering parameters or impedance of contactless passive chips, using common measurement devices such as oscilloscope, personal computer, and directional coupler. The measurements obtained using this method are as accurate as those obtained with vector network analyzer (VNA) measurements, while providing several improvements. First, the method makes it possible to measure a chip’s impedance in activation state, which requires large input power, not compatible with VNA measurements. Second, this method realizes a real-time measurement, which consists in impedance measurement as a function of time. Therefore, this real-time measurement makes it possible to detect and measure the impedance changes of an actual contactless smart card’s integrated circuit during a load modulation communication at different powers. Finally, this real-time impedance measurement gives important information on chips’ electrical characteristics that can be used to optimize near-field communication devices design in order to reduce the power losses within an RF identification tag.
Autors: Benoit Couraud;Thibaut Deleruyelle;Edith Kussener;Rémy Vauché;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Feb 2018, volume: 67, issue:2, pages: 288 - 295
Publisher: IEEE
 
» Real-Time Inter-Frame Histogram Builder for SPAD Image Sensors
Abstract:
CMOS image sensors based on single-photon avalanche-diodes (SPAD) are suitable for 2D and 3D vision. Limited by uncorrelated noise and/or low illumination conditions, image capturing becomes nearly impossible in a single-shot exposure time. Moreover, the depth accuracy is affected by jitter. Therefore, many frames need to be taken to reconstruct the final accurate image. The proposed reconstruction algorithm is based on pixel-wise histogram building. Specifically, a histogram is built on the fly for each pixel of the array from the ongoing acquired frames. This paper presents the design and implementation on FPGA of a real-time pixel-wise inter-frame histogram builder at 1 kfps. The design has been proven with a -pixels SPAD camera. Its remarkable robustness has been demonstrated in harsh conditions, such as 42 kHz of dark count rate (DCR) and high background illumination up to 20 times larger than the DCR. The system has a graphic user interface for 2D/3D imager configuration, image streaming, and pixel-wise histogram streaming.
Autors: Ion Vornicu;Ricardo Carmona-Galán;Ángel Rodríguez-Vázquez;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1576 - 1584
Publisher: IEEE
 
» Real-Time Monitoring of Post-Fault Scenario for Determining Generator Coherency and Transient Stability Through ANN
Abstract:
Power system monitoring and control in real time is a challenging task for modern power system due to large operational constraints. The deployment of phasor measurement units (PMUs) at key locations provides an opportunity for devising effective power system monitoring and control measures. In this study, a new method is proposed to determine the real-time transient stability status and identification of the coherent generator groups by predicting the rotor angle values following a large disturbance through radial basis function neural network. The first six cycles of synchronously sampled post-fault data measurements from PMUs consisting of rotor angles and voltages of generators are taken as the input to the neural network to predict the future state of the system. The proposed method can also determine the synchronism state of the individual machine in real time. The proposed scheme is demonstrated on the IEEE-39 bus test system at different operating conditions.
Autors: Shahbaz A. Siddiqui;Kusum Verma;K. R. Niazi;Manoj Fozdar;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 685 - 692
Publisher: IEEE
 
» Real-Time Optical Spectrum Fourier Transform With Time–Bandwidth Product Compression
Abstract:
We propose and experimentally demonstrate a photonic technique for Fourier transformation of broadband optical spectrum and compression of time–bandwidth product (TBP) simultaneously. Conventionally, an optical spectrum could be Fourier transformed based on the so-called time-spectrum convolution technique with a linearly dispersive delay line. In this paper, a nonlinearly dispersive delay line is implemented by the convolution of an input optical spectrum in the spectral domain with a nonlinearly chirped temporal sinusoidal waveform in the time domain. By specially designing the chirp rate variation of the temporal waveform, an anamorphic Fourier transformation functionality is realized to compress the TBP of output waveform. The key feature of this paper is that it is the first time to our knowledge to carry out the Fourier transformation of an optical spectrum with TBP compression. In addition, since the dispersive delay line could be programmable with high resolution, this technique is adaptable for different optical spectra and realizable for a reconfigurable TBP compression ratio. Experimental results show that the TBP compression ratio is programmable from 1.6 to 3 by engineering the nonlinear dispersive delay line. After reconstructing the Fourier transform of optical spectrum from the output waveforms, the error rate of the recovered waveform is calculated quantitatively. Also, we discussed and proved the possibility to recover the input spectrum only with intensity information. This proposed method is promising to break the big data limitation of the conventional real-time optical spectrum Fourier transformation technique based on the TBP engineering for data compression.
Autors: Hao Sun;Xinyi Zhu;Wei Li;Ninghua Zhu;Ming Li;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 14
Publisher: IEEE
 
» Real-Time Precise Position Tracking With Stepper Motor Using Frequency Modulation Based Microstepping
Abstract:
Microstepping drive for a stepper motor is a well-known technique to improve the stepper motor performance. Normally, microstepping is carried at fixed pulse width planned. However, this method is suitable only when motors are driven at fixed predefined speeds for non-real-time applications. The problem discussed in this paper considers an application where motors need to track a given reference position profile precisely in real time, whose speed is varying at every interval of time. In such a scenario, fixed speed microstep drive does not meet the high pointing requirements and leads to poor system performance. For such applications, an innovative frequency modulation (FM) based microstep drive algorithm is developed that meets the high degree of motor pointing even at higher output angular rates. As per this scheme, pulse width and the number of steps that motor is supposed to move are derived from the reference position itself in a given amount of time, and the motor is actuated with a corresponding number of steps in real time. FM-based microstep drive is implemented with pulse-width modulation based chopper current controller in an optimized way without compromising on the motor torque margins. Transient error plots obtained through experiments clearly show the advantages of FM-based microstepping over fixed rate. This paper presents the design, analysis, simulation, and experimental results of FM-based microstep drive.
Autors: Dhruti Ranjan Gaan;Manoj Kumar;S. Sudhakar;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 693 - 701
Publisher: IEEE
 
» Real-Time Simultaneous Separation and Detection of Chemicals Using Integrated Microcolumn and Surface Plasmon Resonance Imaging Micro-GC
Abstract:
An integrated and miniaturized micro-gas chromatography (GC) with real-time imaging capability for simultaneous chemical separation and detection was developed. Surface plasmon resonance imaging (SPRi) was used as a sensitive and real-time imaging-based detector for various gaseous chemical mixtures, and good gas chromatographs were obtained. The system integrated a home-made miniaturized molecular sieve packed spiral microchannel column with the SPRi chip and real-time chemical separation and detection were demonstrated using alkanes. The chemical separation processes were simulated using COMSOL and matched well with the experimental results. The system enabled the study of chemical separation processes in real-time by miniaturizing and integrating the micro-GC separation and detection units. This approach can be expanded to multidimensional GC development.
Autors: Zijian Du;Francis Tsow;Di Wang;Nongjian Tao;
Appeared in: IEEE Sensors Journal
Publication date: Feb 2018, volume: 18, issue:4, pages: 1351 - 1357
Publisher: IEEE
 
» Realization of Multicore Fiber Reconfigurable Optical Add–Drop Multiplexer
Abstract:
Space-division multiplexing (SDM) is a calling for devices that fully replace their single-mode fiber counterparts. Fast optical switches represent one such type of key devices. In this letter, we present a free-space optical add–drop multiplexer for multicore fiber (MCF) optical communications. Microelectromechanical mirrors were used as the optical switching element. We first detail the implementation steps leading to the proposed device and then characterize its performance in terms of crosstalk and insertion loss. Overall average crosstalk is around −38 dB, while insertion losses remain large. The device investigated here is another step towards the practical adoption of SDM for optical networks based on MCFs.
Autors: Mahmoud Gadalla;Véronique François;Bora Ung;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:3, pages: 281 - 284
Publisher: IEEE
 
» Reconfigurable 2-bit Fixed-Frequency Beam Steering Array Based on Microstrip Line
Abstract:
In this paper, the scanning performance at a fixed frequency of the 2-bit linear array is presented. Then, for the first time, a microstrip line that supports a traveling wave is used as bit phase sources with any bit number to construct reconfigurable fixed-frequency beam steering bit arrays. Using the ) open cavity as the radiating element, a ten-element reconfigurable 2-bit fixed-frequency beam steering array operating at 5 GHz is designed and fabricated to verify the idea. By sampling two feed points with a separation distance of a quarter wavelength on one side of the microstrip line, the phase states of 0° and −90° are obtained; other two counterpart points on the other side of the line can offer the phase states of −180° and −270°, producing the required 2-bit unit. Five prototypes representing five array configurations show a measured scan range of 94° between −48° and +46° at 5 GHz, and the measured five beams show good quality and consistency: the peak gains range from 10.01 to 12.33 dBi with a gain variation of only 2.32 dB and the 3 dB beam widths vary between 13° and 17°.
Autors: Le Chang;Yue Li;Zhijun Zhang;Zhenghe Feng;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2018, volume: 66, issue:2, pages: 683 - 691
Publisher: IEEE
 
» Reconfigurable Envelope Generation of Optical Pulse Train Based on Discrete Fourier Transform
Abstract:
We experimentally demonstrate a fiber-based reconfigurable system for programming the envelope of high-speed optical pulse train by using fractional-rate multilevel amplitude modulation. Amplitude-modulated optical pulse trains undergo the discrete Fourier transform (DFT) realized by the temporal Talbot effect in a dispersive fiber. Consequently, rate-multiplied optical pulse trains with programmable envelopes can be achieved. In this letter, we report experimental synthesis of ~80-GHz optical pulse trains with expectant binary patterns, parabolic, square, and triangular envelopes. We also consider practical implementation issues and numerically analyze the influence from the deviation of modulation coefficients and finite extinction ratio of the Mach–Zehnder modulator on the generated pulses.
Autors: Qijie Xie;Chester Shu;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:3, pages: 242 - 245
Publisher: IEEE
 
» Reconfigurable Grounded Vector Antenna for 3-D Electromagnetic Direction-Finding Applications
Abstract:
In this letter, a reconfigurable grounded wideband antenna is proposed in view of vector sensor applications. This antenna combines two orthogonal and colocated semicircular arrays of  Vivaldi antennas mounted over a metallic support. The radiation patterns of two wideband magnetic dipoles and one wideband electric dipole can be synthesized thanks to an appropriate antenna excitation. Measurement results are in good agreement with the simulated results obtained from full-wave electromagnetic simulations. The proposed antenna exhibits stable radiation patterns over a wide impedance bandwidth of 1.69:1, a high radiation efficiency and a good isolation between the antenna input ports. This antenna is a good candidate for wideband three-dimensional direction-finding using a vector sensor.
Autors: Johan Duplouy;Christophe Morlaas;Hervé Aubert;Patrick Potier;Philippe Pouliguen;Christopher Djoma;
Appeared in: IEEE Antennas and Wireless Propagation Letters
Publication date: Feb 2018, volume: 17, issue:2, pages: 197 - 200
Publisher: IEEE
 
» Reconfigurable Sorting of Nanoparticles on a Thermal Tuning Silicon Based Optofluidic Chip
Abstract:
We numerically demonstrate a scheme of optofluidic sorting of nanoparticles on a silicon-based lab-on-a-chip system, with reconfigurable and multilevel sorting size thresholds. Size-dependent sorting of nanoparticles originates from the size-dependent distribution of trapping potential wells, which determines whether a nanoparticle can jump back and forth between parallel waveguides in weakly coupling condition. In numerical modeling, we find that it is easier for larger ones to transfer and the size threshold is power ratio dependent. By setting a thermal tuning ring-assisted Mach–Zehnder interferometer ahead, we can adjust effectively the input power ratio of the parallel waveguides as well as the potential well distribution across them, working as a thermal tuning reconfigurable sorting unit. Consequently, a tree cascaded unit with different thresholds is also presented to be a reconfigurable multilevel sorting unit. The proposed design offers a simple and ultracompact scheme for the reconfigurable and multilevel optofluidic sorting of nanoparticles on thermo-optofluidics chip for the first time.
Autors: Xiaofu Xu;Yuming Dong;Guanghui Wang;Wenxiang Jiao;Zhoufeng Ying;Ho-pui Ho;Xuping Zhang;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 7
Publisher: IEEE
 
» Reconfigurable Split-Ring Resonators Using Pneumatic Levitation System
Abstract:
In this paper, a pneumatic levitation system is proposed to provide a contactless and metal free platform for dynamically altering the structural arrangement of split-ring resonators in an incident electromagnetic wave. One split ring is placed on a pneumatically levitated platform controlled by different levels of air pressure, and another identical but static split ring is placed underneath to form a broadside coupled arrangement. The proposed pneumatic levitation system has the capability to precisely control the relative orientation of the split ring to the desired rotational angle for on-demand reconfigurability without a sophisticated electrical or mechanical structure. In addition to the rotational angle, the separation between two SRRs can also be reliably controlled by adjusting the pneumatic pressure. The combination of both of these controls enables a large frequency configuration range for broadside coupled SRRs. The corresponding frequency tunability with a 35% bandwidth is validated by both simulations and measurements.
Autors: Xutao Tang;Iryna E. Khodasevych;Wayne S. T. Rowe;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Feb 2018, volume: 66, issue:2, pages: 763 - 770
Publisher: IEEE
 
» Rectifier Efficiency [Enigmas, etc.]
Abstract:
Various puzzles, humorous definitions, or mathematical recreations - usually having some relevance to electrical engineering - that should engage the interest of readers.
Autors: Takashi Ohira;
Appeared in: IEEE Microwave Magazine
Publication date: Feb 2018, volume: 19, issue:1, pages: 136 - 136
Publisher: IEEE
 
» Recursive Spectral Meta-Learner for Online Combining Different Fault Classifiers
Abstract:
This paper considers the problem of fault classification when different fault classifiers are performed simultaneously. Based on spectral meta-learner (SML) proposed by Parisi et al., its recursive version, i.e., recursive SML (RSML) is developed for online combining the potentially conflicting classification information. Considering different statistical properties of faults occurring at different time intervals, the binary classification information is recursively utilized. By introducing a forgetting factor, the leading eigenvector of the estimate of the time-varying covariance matrix is used as the weight vector for each classifier. Rank-one modification is then used for calculating the eigenvector in order to reduce the online computational complexity. The performance of RSML is strictly analyzed in a statistical sense, including the effect of recursive calculation and conditional dependence of different classifiers on the weight vector. Compared with majority voting and SML, a higher balanced accuracy of RSML can be verified by the benchmark Tennessee Eastman process.
Autors: Maoyin Chen;Jun Shang;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Feb 2018, volume: 63, issue:2, pages: 586 - 593
Publisher: IEEE
 
» Reduced-Reference Image Quality Assessment in Free-Energy Principle and Sparse Representation
Abstract:
The free-energy principle in recent studies of brain theory and neuroscience models the perception and understanding of the outside scene as an active inference process, in which the brain tries to account for the visual scene with an internal generative model. Specifically, with the internal generative model, the brain yields corresponding predictions for its encountered visual scenes. Then, the discrepancy between the visual input and its brain prediction should be closely related to the quality of perceptions. On the other hand, sparse representation has been evidenced to resemble the strategy of the primary visual cortex in the brain for representing natural images. With the strong neurobiological support for sparse representation, in this paper, we approximate the internal generative model with sparse representation and propose an image quality metric accordingly, which is named FSI (free-energy principle and sparse representation-based index for image quality assessment). In FSI, the reference and distorted images are, respectively, predicted by the sparse representation at first. Then, the difference between the entropies of the prediction discrepancies is defined to measure the image quality. Experimental results on four large-scale image databases confirm the effectiveness of the FSI and its superiority over representative image quality assessment methods. The FSI belongs to reduced-reference methods, and it only needs a single number from the reference image for quality estimation.
Autors: Yutao Liu;Guangtao Zhai;Ke Gu;Xianming Liu;Debin Zhao;Wen Gao;
Appeared in: IEEE Transactions on Multimedia
Publication date: Feb 2018, volume: 20, issue:2, pages: 379 - 391
Publisher: IEEE
 
» Reduced-Threshold Emission of Capillary Filled by Doped-Dye Cholesteric Liquid Crystals With Photo-Alignment Polyimide Films
Abstract:
A microcavity laser is reported using dye-doped cholesteric liquid crystals (CLCs) filled in a glass capillary with photo-alignment polyimide films. This laser runs based on the properties that a CLC has a refractive index much higher than that of glass, so whispering-gallery-mode (WGM) laser and distributed-feedback-mode lasers are included in the emission spectrum. We obtain a low threshold energy of , establish the shift of 3.04 nm of the WGMs in the temperature range 43–48 °C, and investigate electric field tunability.
Autors: Yue-Lan Lu;Xiang-Bao Yin;Zuo-Ren Xiong;Yue Yang;Wei-Min Sun;Yong-Jun Liu;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 7
Publisher: IEEE
 
» Reducing Conservatism in an $H_{infty }$ Robust State-Feedback Control Design of T–S Fuzzy Systems: A Nonmonotonic Approach
Abstract:
This paper proposes an robust state-feedback controller design for uncertain Takagi–Sugeno fuzzy systems using a nonmonotonic Lyapunov function. In the nonmonotonic approach, the monotonicity requirement of the Lyapunov function is relaxed by allowing it to increase locally. Based on the nonmonotonic Lyapunov function approach, sufficient conditions for the existence of a robust state-feedback controller that guarantees stability and a prescribed performance are given in terms of linear matrix inequalities. The proposed design technique is shown to be less conservative than the existing -samples variations of the Lyapunov function. The effectiveness of the proposed approach is further illustrated via numerical examples.
Autors: Alireza Nasiri;Sing Kiong Nguang;Akshya Swain;Dhafer J. Almakhles;
Appeared in: IEEE Transactions on Fuzzy Systems
Publication date: Feb 2018, volume: 26, issue:1, pages: 386 - 390
Publisher: IEEE
 
» Reducing Energy Costs in Electric-Motor-Driven Systems: Savings Through Output Power Reduction and Energy Regeneration
Abstract:
Electric-motor systems convert nearly half of worldwide electric energy into the mechanical energy ultimately used in the final application or process. The integral optimization of electric-motor-driven systems (EMODSs), including the use of high-efficiency, well-sized components, is the key strategy to effectively maximize their overall efficiency. However, the largest energy savings potential in motor-driven systems is associated with the reduction of the power required by the driven equipment through speed/torque control and/or with the partial reuse of the energy stored in the system. In this article, the basic principles and some practical examples of output power reduction and energy regeneration in EMODSs are presented.
Autors: Fernando J.T.E. Ferreira;Anibal T. de Almeida;
Appeared in: IEEE Industry Applications Magazine
Publication date: Feb 2018, volume: 24, issue:1, pages: 84 - 97
Publisher: IEEE
 
» Reduction of Variability in Junctionless and Inversion-Mode FinFETs by Stringer Gate Structure
Abstract:
Variabilities such as threshold voltage, on-current, and subthreshold swing due to random dopant fluctuation (RDF), work function variation (WFV), and line edge roughness (LER) are studied in junctionless (JL) stringer FinFETs and compared with inversion-mode devices using technology computer-aided design analysis. Compared with a conventional JL FinFET, the stringer gate JL FinFET shows suppressed variabilities due to RDF, WFV, and LER with better gate controllability and larger effective gate length, respectively.
Autors: Jungsik Kim;Jin-Woo Han;M. Meyyappan;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2018, volume: 65, issue:2, pages: 470 - 475
Publisher: IEEE
 
» Refractive Index and Temperature Sensing Based on an Optoelectronic Oscillator Incorporating a Fabry–Perot Fiber Bragg Grating
Abstract:
An ultrafast high-sensitivity refractive index (RI) and temperature-sensing system based on an optoelectronic oscillator (OEO) is proposed and demonstrated in this paper. A Fabry–Perot fiber Bragg grating (FP-FBG), which combines a gap with two FBGs in a silica V-shaped slot and characterizes a narrow notch in the reflection spectrum, is incorporated in the OEO to implement a microwave photonic filter and perform oscillating frequency selection. A microwave signal is generated by the OEO, whose oscillating frequency is determined by the center frequency of the FP-FBG notch, which varies with the surrounding environments. The RI or the temperature change can be accordingly measured by monitoring the frequency shift of the microwave signal using an electrical spectrum analyzer or a digital signal processor. An experiment is performed to verify the proposal. An RI sensitivity of 413.8 MHz/0.001RIU and a temperature sensitivity of 2516 MHz/°C are successively demonstrated.
Autors: Yuguang Yang;Muguang Wang;Ya Shen;Yu Tang;Jing Zhang;Yue Wu;Shiying Xiao;Jingxuan Liu;Buzheng Wei;Qi Ding;Shuisheng Jian;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 9
Publisher: IEEE
 
» Region Growing for Segmenting Green Microalgae Images
Abstract:
We describe a specialized methodology for segmenting 2D microscopy digital images of freshwater green microalgae. The goal is to obtain representative algae shapes to extract morphological features to be employed in a posterior step of taxonomical classification of the species. The proposed methodology relies on the seeded region growing principle and on a fine-tuned filtering preprocessing stage to smooth the input image. A contrast enhancement process then takes place to highlight algae regions on a binary pre-segmentation image. This binary image is also employed to determine where to place the seed points and to estimate the statistical probability distributions that characterize the target regions, i.e., the algae areas and the background, respectively. These preliminary stages produce the required information to set the homogeneity criterion for region growing. We evaluate the proposed methodology by comparing its resulting segmentations with a set of corresponding ground-truth segmentations (provided by an expert biologist) and also with segmentations obtained with existing strategies. The experimental results show that our solution achieves highly accurate segmentation rates with greater efficiency, as compared with the performance of standard segmentation approaches and with an alternative previous solution, based on level-sets, also specialized to handle this particular problem.
Autors: Vinicius R. P. Borges;Maria Cristina F. de Oliveira;Thaís Garcia Silva;Armando Augusto Henriques Vieira;Bernd Hamann;
Appeared in: IEEE/ACM Transactions on Computational Biology and Bioinformatics
Publication date: Feb 2018, volume: 15, issue:1, pages: 257 - 270
Publisher: IEEE
 
» Regulatory Policy Awareness and Environmental Supply Chain Cooperation in China: A Regulatory-Exchange-Theoretic Perspective
Abstract:
Some developed countries have enacted extended producer responsibility regulations that facilitate the diffusion of environmental supply chain cooperation (ESCC) practices among manufacturers. Developing countries, such as China, have adopted similar but generally flexible and voluntary regulations and policies. Using exchange theory with a focus on regulatory aspects as the theoretical lens, this paper develops propositions to examine if awareness of voluntary environmental regulatory policies is different among manufacturers as well as the relationship to ESCC practices adoption. Results from cluster analysis and multivariate analysis of variance for 308 responses identify three categories of Chinese manufacturers with respect to their awareness of environmental regulatory policies. These three categories include savvy, attentive, and nescient manufacturers. It was found that manufacturers characterized with higher environmental regulatory awareness tend to implement ESCC practices more intensively. Hierarchical regression analysis was further used to examine the relationship between awareness of regulatory policies and ESCC practices. Awareness of domestic regulatory policies has positive effects on green purchasing only for savvy manufacturers. Regression results show a nonlinear relationship between awareness of domestic regulatory policies and customer cooperation with environmental concerns, from slightly positive for nescient manufacturers and slightly negative for attentive manufacturers to significantly positive for savvy manufacturers.
Autors: Qinghua Zhu;Joseph Sarkis;Kee-Hung Lai;
Appeared in: IEEE Transactions on Engineering Management
Publication date: Feb 2018, volume: 65, issue:1, pages: 46 - 58
Publisher: IEEE
 
» Reliability Assessment of Microgrids With Local and Mobile Generation, Time-Dependent Profiles, and Intraday Reconfiguration
Abstract:
In this paper, the notion of reliability assessment for distribution system applications is revisited to include a number of practices emerging in the smart grid context. The information on the variations in time of generation and demand is taken into account to establish a reference network configuration that considers the definition of an intraday reconfiguration strategy based on conventional load profiles for different categories of demand (residential, industrial, and commercial). After a fault, the service restoration process is aided by the formation of autonomous islanded subsystems (microgrids). During the restoration period, each subsystem is able to serve the local demand in a given portion of the network and to reconnect to the main network through proper synchronization. Dedicated solutions for mobile generation and storage are exploited to reach the nodes needing additional supply. A sequential Monte Carlo method is used to carry out reliability assessment. The use of this method incorporates the effects of interfering near-coincident faults and time-varying load and local generation patterns. The application on a real distribution network is presented, showing the probability distributions of the reliability indicators (power and energy not supplied), as well as the breakdown of these indicators for different demand categories.
Autors: Pilar Meneses de Quevedo;Javier Contreras;Andrea Mazza;Gianfranco Chicco;Radu Porumb;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 61 - 72
Publisher: IEEE
 
» Reliable and Compact 3- and 4-Bit Phase Shifters Using MEMS SP4T and SP8T Switches
Abstract:
This paper presents radio frequency (RF) micro-electromechanical system-based 3- and 4-bit phase shifters using single-pole-four-throw (SP4T) and single-pole-eight-throw (SP8T) switches. The design is fabricated on alumina substrate using a surface micromachining process. SP4T and SP8T switches demonstrate measured return loss of >16 dB, worst case insertion loss of 1.66 dB, and isolation of >13.6 dB up to 40 GHz. Total area of the SP4T and SP8T switches is 0.98 mm2 and 1.66 mm2, respectively. Switches are capable of handling 1 W of incident RF power and can sustain up to 1 billion cycles at 85°C. Finally, 3- and 4-bit phase shifters deliver measured return loss of >12 dB, average insertion loss of <5.4 dB, and average phase error of 1.65° at 35 GHz. The total area of the phase shifter (4-bit) is 7.5 mm2, which is lowest reported till date. Reliability tests of phase shifters demonstrate >1 billion cycles with 0.1 W of power in cold switching. In addition, phase shifters also worked satisfactory up to >400 million cycles with 0.5 W of power at 85 °C in hot switching condition. Devices were enclosed within a low-cost package and characterized them systematically. [2017-0104]
Autors: Sukomal Dey;Shiban K. Koul;Ajay K. Poddar;Ulrich L. Rohde;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Feb 2018, volume: 27, issue:1, pages: 113 - 124
Publisher: IEEE
 
» Reliable and Energy-Efficient Hybrid Screen Mirroring Multicast System
Abstract:
This paper presents a reliable and energy-efficient hybrid screen mirroring multicast system for sharing high-quality real-time multimedia service with adjacent mobile devices over WiFi network. The proposed system employs overhearing-based multicast transmission scheme with Raptor codes and NACK-based retransmission to overcome well-known WiFi multicast problems such as low transmission rate and high packet loss rate. Furthermore, to save energy on mobile devices, the proposed system not only shapes the screen mirroring traffic, but also determines the target sink device and Raptor encoding parameters such as the number of source symbols, symbol size, and code rate while considering the energy consumption and processing delay of the Raptor encoding and decoding processes. The proposed system is fully implemented in Linux-based single board computers and examined in real WiFi network. Compared to existing systems, the proposed system can achieve good energy efficiency while providing a high-quality screen mirroring service.
Autors: Yunmin Go;Hwangjun Song;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Feb 2018, volume: 17, issue:2, pages: 433 - 446
Publisher: IEEE
 
» Remembering Claude Shannon [Essay]
Abstract:
Presents a tribute to Claude Shannon. The IEEE Information Theory Society launched a global initiative to commemorate Claude Shannon’s centenary in 2016. This was part of an IEEE effort to pay due tribute to accomplished names whose venerable contributions have shaped our profession. Practically speaking, the world we live in today owes a lot to Shannon. Shannon greatly influenced technology and digital communications in such a way that has rightfully earned him the nickname, the “father of the Information Age.” This man gave the world machine learning and information theory. His work paved the way for the creation of the knowledge-intensive societies we live in today. He put together the fundamental theoretical basis for how we communicate, store, secure, analyze, and measure information in the digital world.
Autors: Michael P. Salem;
Appeared in: IEEE Potentials
Publication date: Feb 2018, volume: 37, issue:1, pages: 7 - 8
Publisher: IEEE
 
» Remembering Prof. Thomas B.A. Senior [In Memoriam]
Abstract:
Autors: Kamal Sarabandi;
Appeared in: IEEE Antennas and Propagation Magazine
Publication date: Feb 2018, volume: 60, issue:1, pages: 136 - 137
Publisher: IEEE
 
» Remote Sensing Image Classification With Large-Scale Gaussian Processes
Abstract:
Current remote sensing image classification problems have to deal with an unprecedented amount of heterogeneous and complex data sources. Upcoming missions will soon provide large data streams that will make land cover/use classification difficult. Machine-learning classifiers can help at this, and many methods are currently available. A popular kernel classifier is the Gaussian process classifier (GPC), since it approaches the classification problem with a solid probabilistic treatment, thus yielding confidence intervals for the predictions as well as very competitive results to the state-of-the-art neural networks and support vector machines. However, its computational cost is prohibitive for large-scale applications, and constitutes the main obstacle precluding wide adoption. This paper tackles this problem by introducing two novel efficient methodologies for GP classification. We first include the standard random Fourier features approximation into GPC, which largely decreases its computational cost and permits large-scale remote sensing image classification. In addition, we propose a model which avoids randomly sampling a number of Fourier frequencies and alternatively learns the optimal ones within a variational Bayes approach. The performance of the proposed methods is illustrated in complex problems of cloud detection from multispectral imagery and infrared sounding data. Excellent empirical results support the proposal in both computational cost and accuracy.
Autors: Pablo Morales-Álvarez;Adrián Pérez-Suay;Rafael Molina;Gustau Camps-Valls;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2018, volume: 56, issue:2, pages: 1103 - 1114
Publisher: IEEE
 
» Remote Sensing Image Registration Using Convolutional Neural Network Features
Abstract:
Successful remote sensing image registration is an important step for many remote sensing applications. The scale-invariant feature transform (SIFT) is a well-known method for remote sensing image registration, with many variants of SIFT proposed. However, it only uses local low-level information, and loses much middle- or high-level information to register. Image features extracted by a convolutional neural network (CNN) have achieved the state-of-the-art performance for image classification and retrieval problems, and can provide much middle- and high-level information for remote sensing image registration. Hence, in this letter, we investigate how to calculate the CNN feature, and study the way to fuse SIFT and CNN features for remote sensing image registration. The experimental results demonstrate that the proposed method yields a better registration performance in terms of both the aligning accuracy and the number of correct correspondences.
Autors: Famao Ye;Yanfei Su;Hui Xiao;Xuqing Zhao;Weidong Min;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Feb 2018, volume: 15, issue:2, pages: 232 - 236
Publisher: IEEE
 
» Repairing Algebraic Geometry Codes
Abstract:
Minimum storage regenerating codes have minimum storage of data in each node and therefore are maximal distance separable (for short) codes. Thus, the number of nodes is upper-bounded by , where is the bits of data stored in each node. From both theoretical and practical points of view (see the details in Section 1), it is natural to consider regenerating codes that nearly have minimum storage of data, and meanwhile, the number of nodes is unbounded. One of the candidates for such regenerating codes is an algebraic geometry code. In this paper, we generalize the repairing algorithm of Reed–Solomon codes given by Guruswami and Wotters to algebraic geometry codes and present a repairing algorithm for arbitrary one-point algebraic geometry codes. By applying our repairing algorithm to the one-point algebraic geometry codes based on the Garcia–Stichtenoth tower, one can repair a code of rate and length over with bandwidth for any with a real . In addition, storage in each node for an algebraic geometry code is close to the minimum storage. Due to nice structures of Hermitian curves, repairing of Hermitian codes is also investigated. As a result, we are able to show - hat algebraic geometry codes are regenerating codes with good parameters.
Autors: Lingfei Jin;Yuan Luo;Chaoping Xing;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 900 - 908
Publisher: IEEE
 
» Replacement Policy Adaptable Miss Curve Estimation for Efficient Cache Partitioning
Abstract:
Cache replacement policies and cache partitioning are well-known cache management techniques which aim to eliminate inter- and intra-application contention caused by co-running applications, respectively. Since replacement policies can change applications’ behavior on a shared last-level cache, they have a massive impact on cache partitioning. Furthermore, cache partitioning determines the capacity allocated to each application affecting incorporated replacement policy. However, their interoperability has not been thoroughly explored. Since existing cache partitioning methods are tailored to specific replacement policies to reduce overheads for characterization of applications’ behavior, they may lead to suboptimal partitioning results when incorporated with the up-to-date replacement policies. In cache partitioning, miss curve estimation is a key component to relax this restriction which can reflect the dependency between a replacement policy and cache partitioning on partitioning decision. To tackle this issue, we propose a replacement policy adaptable miss curve estimation (RME) which estimates dynamic workload patterns according to any arbitrary replacement policy and to given applications with low overhead. In addition, RME considers asymmetry of miss latency by miss type, thus the impact of miss curve on cache partitioning can be reflected more accurately. The experimental results support the efficiency of RME and show that RME-based cache partitioning cooperated with high-performance replacement policies can minimize both inter- and intra-application interference successfully.
Autors: Byunghoon Lee;Kwangsu Kim;Eui-Young Chung;
Appeared in: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Publication date: Feb 2018, volume: 37, issue:2, pages: 445 - 457
Publisher: IEEE
 
» Reservoir Computing Meets Smart Grids: Attack Detection Using Delayed Feedback Networks
Abstract:
A new method for attack detection of smart grids with wind power generators using reservoir computing (RC) is introduced in this paper. RC is an energy-efficient computing paradigm within the field of neuromorphic computing and the delayed feedback networks (DFNs) implementation of RC has shown superior performance in many classification tasks. The combination of temporal encoding, DFN, and a multilayer perceptron (MLP) as the output readout layer is shown to yield performance improvement over existing attack detection methods such as MLPs, support vector machines (SVM), and conventional state vector estimation (SVE) in terms of attack detection in smart grids. The proposed algorithms are shown to be more robust than MLP and SVE in dealing with different variables such as the amplitude of the attack, attack types, and the number of compromised measurements in smart grids. The attack detection rate for the proposed RC-based system is higher than 99%, based on the accuracy metric for the average of 10 000 simulations.
Autors: Kian Hamedani;Lingjia Liu;Rachad Atat;Jinsong Wu;Yang Yi;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Feb 2018, volume: 14, issue:2, pages: 734 - 743
Publisher: IEEE
 
» Resonance-Based Procedure for Locating Failed Luminaires in AGL Systems
Abstract:
Aeronautical ground lighting (AGL) systems provide a visual reference for aircraft during airport operations. Fast detection and location of failed luminaires is an important safety concern in AGL systems. In the event of luminaire failure, AGL transformers introduce harmonic currents. Resonances can increase harmonics, worsening the problem. This paper presents analytical expressions for determining resonance frequencies in AGL systems, as well as a simple procedure based on these expressions for locating failed luminaires from measurements.
Autors: Daniel Vidal;Lluís Monjo;Luis Sainz;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 106 - 114
Publisher: IEEE
 
» Resonances in Bianisotropic Layers
Abstract:
This paper rigorously studies the resonant transmission of electromagnetic waves around embedded trapped modes in bianisotropic films and derives the dispersion relations, the embedded mode condition, and the coupling and tunneling of the evanescent wave within the reciprocal lossless bianisotropic layer. The Berreman's matrix model has been developed to obtain the transmission characteristics through the bianisotropic film. When the layer structure was perturbed, a resonance phenomenon was perceived around the distinct trapped modes; these resonances lead to anomalous transmission and field amplifications around the trapped mode frequencies. The parameters of the magnetoelectric tensors can be used to control the number of the trapped modes and accordingly the resonances in the bianisotropic layer material.
Autors: Faroq Razzaz;Majeed A. S. Alkanhal;
Appeared in: IEEE Photonics Journal
Publication date: Feb 2018, volume: 10, issue:1, pages: 1 - 12
Publisher: IEEE
 
» Resource Allocation for Multiple Device-to-Device Cluster Multicast Communications Underlay Cellular Networks
Abstract:
A practically efficient resource allocation scheme is designed for multiple device-to-device cluster (D2DC) multicast communications underlay cellular networks. The transmit power and the channel are allocated to D2DC to maximize the sum effective throughput provided that the cellular communications maintain a certain level of quality of service. We devise a channel allocation scheme using partial information of device locations. For this, we derive the outage probability and an effective throughput of D2DC communications in approximate forms. Numerical results reveal that, when the number of D2DC receivers is large, the proposed scheme achieves the near optimal sum effective throughput, which can be obtained by using full information of device locations.
Autors: Jong-Ho Kim;Jingon Joung;Jeong Woo Lee;
Appeared in: IEEE Communications Letters
Publication date: Feb 2018, volume: 22, issue:2, pages: 412 - 415
Publisher: IEEE
 
» Resource Dependency Processing in Web Scaling Frameworks
Abstract:
The upsurge of mobile devices paired with highly interactive social web applications generates enormous amounts of requests web services have to deal with. Consequently in our previous work, a novel request flow scheme with scalable components was proposed for storing interdependent, permanently updated resources in a database. The major challenge is to process dependencies in an optimal fashion while maintaining dependency constraints. In this work, three research objectives are evaluated by examining resource dependencies and their key graph measurements. An all-sources longest-path algorithm is presented for efficient processing and dependencies are analysed to find correlations between performance and graph measures. Two algorithms basing their parameters on six real-world web service structures, e.g., Facebook Graph API are developed to generate dependency graphs and a model is developed to estimate performance based on resource parameters. An evaluation of four graph series discusses performance effects of different graph structures. The results of an evaluation of 2,000 web services with over 850 thousand resources and 6 million requests indicate that resource dependency processing can be up to a factor of two faster compared to a traditional processing approach while an average model fit of 97 percent allows an accurate prediction.
Autors: Thomas Fankhauser;Qi Wang;Ansgar Gerlicher;Christos Grecos;
Appeared in: IEEE Transactions on Services Computing
Publication date: Feb 2018, volume: 11, issue:1, pages: 155 - 168
Publisher: IEEE
 
» Results From the Deep Convective Clouds-Based Response Versus Scan-Angle Characterization for the MODIS Reflective Solar Bands
Abstract:
The Terra and Aqua Moderate-Resolution Imaging Spectroradiometer (MODIS) scan mirror reflectance is a function of the angle of incidence (AOI) and was characterized prior to launch by the instrument vendor. The relative change of the prelaunch response versus scan angle (RVS) is tracked and linearly scaled on-orbit using observations at two AOIs of 11.2° and 50.2° corresponding to the moon view and solar diffuser, respectively. As the missions continue to operate well beyond their design life of six years, the assumption of linear scaling between the two AOIs is known to be inadequate in accurately characterizing the RVS, particularly at short wavelengths. Consequently, an enhanced approach of supplementing the on-board measurements with response trends from desert pseudoinvariant calibration sites (PICS) was formulated in MODIS Collection 6 (C6). An underlying assumption for the continued effectiveness of this approach is the long-term (multiyear) and short-term (month to month) stability of the PICS. Previous work has shown that the deep convective clouds (DCC) can also be used to monitor the on-orbit RVS performance with less trend uncertainties compared with desert sites. In this paper, the raw sensor response to the DCC is used to characterize the on-orbit RVS on a band and mirror-side basis. These DCC-based RVS results are compared with those of C6 PICS-based RVS, showing an agreement within 2% observed in most cases. The pros and cons of using a DCC-based RVS approach are also discussed in this paper. Although this reaffirms the efficacy of the C6 PICS-based RVS, the DCC-based RVS approach presents itself as an effective alternative for future considerations. Potential applications of this approach to other instruments, such as Suomi National Polar-orbiting Partnership, Joint Polar Satellite Systems, and Visible Infrared Imaging Radiometer Suite, are also discussed.
Autors: Amit Angal;Xiaoxiong Xiong;Qiaozhen Mu;David R. Doelling;Rajendra Bhatt;Aisheng Wu;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2018, volume: 56, issue:2, pages: 1115 - 1128
Publisher: IEEE
 
» Reverse Approximate Nearest Neighbor Queries
Abstract:
Given a set of facilities and a set of users, a reverse nearest neighbors (RNN) query retrieves every user for which the query facility is its closest facility. Since is the closest facility to , the user is said to be influenced by . In this paper, we propose a relaxed definition of influence where a user is said to be influenced by not only its closest facility but also every other facility that is almost as close to as its closest facility is. Based on this definition of influence, we propose reverse approximate nearest neighbors (RANN) queries. Formally, given a value , an RANN query returns every user for which where denotes the distance between a user and its nearest facility, i.e., is an approximate nearest neighbor of . In this paper, we study both snapshot and continuous versions of RANN queries. In a snapshot RANN query, the underlying data sets do not change and the results of a query are to be computed only once. In the continuous version, the users continuously change their locations and the results of RANN queries are to be continuously monitored. Based on effective pruning techniques and several non-trivial observations, we propose efficient RANN query processing algorithms for both the snapshot and continuous RANN queries. We conduct extensive experiments on both real and synthetic da
Autors: Arif Hidayat;Shiyu Yang;Muhammad Aamir Cheema;David Taniar;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Feb 2018, volume: 30, issue:2, pages: 339 - 352
Publisher: IEEE
 
» Review of Micro Thermoelectric Generator
Abstract:
Used for thermal energy harvesting, thermoelectric generator (TEG) can convert heat into electricity directly. Structurally, the main part of TEG is the thermopile, which consists of thermocouples connected in series electrically and in parallel thermally. Benefiting from massive progress achieved in a microelectromechanical systems technology, micro TEG (-TEG) with advantages of small volume and high output voltage has obtained attention in recent 20 years. The review gives a comprehensive survey of the development and current status of -TEG. First, the principle of operation is introduced and some key parameters used for characterizing the performance of -TEG are highlighted. Next, -TEGs are classified from the perspectives of structure, material, and fabrication technology. Then, almost all the relevant works are summarized for the convenience of comparison and reference. Summarized information includes the structure, material property, fabrication technology, output performance, and so on. This will provide readers with an overall evaluation of different studies and guide them in choosing the suitable -TEGs for their applications. In addition, the existing and potential applications of -TEG are shown, especially the applications in the Internet of things. Finally, we summarize the challenges encountered in improving the output power of -TEG and predicted that more researchers would focus their efforts on the flexible structur- -TEG, and combination of -TEG and other energy harvestings. With the emergence of more low-power devices and the gradual improvement of ZT value of the thermoelectric material, -TEG is promising for applications in various fields. [2017-0610]
Autors: Jiabin Yan;Xiaoping Liao;Deyang Yan;Youguo Chen;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Feb 2018, volume: 27, issue:1, pages: 1 - 18
Publisher: IEEE
 
» Rewarding Work in IEEE IAS [Pathways]
Abstract:
Reports on the rewarding experiences of joining the IAS Society.
Autors: David Eng;
Appeared in: IEEE Industry Applications Magazine
Publication date: Feb 2018, volume: 24, issue:1, pages: 116 - 117
Publisher: IEEE
 
» Rhythmic Extended Kalman Filter for Gait Rehabilitation Motion Estimation and Segmentation
Abstract:
This paper proposes a method to enable the use of non-intrusive, small, wearable, and wireless sensors to estimate the pose of the lower body during gait and other periodic motions and to extract objective performance measures useful for physiotherapy. The Rhythmic Extended Kalman Filter (Rhythmic-EKF) algorithm is developed to estimate the pose, learn an individualized model of periodic movement over time, and use the learned model to improve pose estimation. The proposed approach learns a canonical dynamical system model of the movement during online observation, which is used to accurately model the acceleration during pose estimation. The canonical dynamical system models the motion as a periodic signal. The estimated phase and frequency of the motion also allow the proposed approach to segment the motion into repetitions and extract useful features, such as gait symmetry, step length, and mean joint movement and variance. The algorithm is shown to outperform the extended Kalman filter in simulation, on healthy participant data, and stroke patient data. For the healthy participant marching dataset, the Rhythmic-EKF improves joint acceleration and velocity estimates over regular EKF by 40% and 37%, respectively, estimates joint angles with 2.4° root mean squared error, and segments the motion into repetitions with 96% accuracy.
Autors: Vladimir Joukov;Vincent Bonnet;Michelle Karg;Gentiane Venture;Dana Kulić;
Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Publication date: Feb 2018, volume: 26, issue:2, pages: 407 - 418
Publisher: IEEE
 
» RIN Mitigation and Transmission Performance Enhancement With Forward Broadband Pump
Abstract:
We demonstrate that using a broadband, first order, and coherent pump laser enables effective and efficient forward-pumped distributed Raman amplification for long-haul transmission systems, thanks to the simultaneous suppression of ASE noise and RIN-related penalty. We show in both experiments and simulation that this scheme extends the reach of Gb/s DP-QPSK WDM transmission by a minimum of 50%, compared with low RIN Bi-doped fibre laser and other commercially available pump lasers. Moreover, it requires very low forward pump power, and maintains uniform/symmetric signal power distribution which allows effective nonlinearity compensation.
Autors: M. Tan;P. Rosa;S. T. Le;V. V. Dvoyrin;Md. A. Iqbal;S. Sugavanam;S. K. Turitsyn;P. Harper;
Appeared in: IEEE Photonics Technology Letters
Publication date: Feb 2018, volume: 30, issue:3, pages: 254 - 257
Publisher: IEEE
 
» Robot Training With Vector Fields Based on Stroke Survivors’ Individual Movement Statistics
Abstract:
The wide variation in upper extremity motor impairments among stroke survivors necessitates more intelligent methods of customized therapy. However, current strategies for characterizing individual motor impairments are limited by the use of traditional clinical assessments (e.g., Fugl-Meyer) and simple engineering metrics (e.g., goal-directed performance). Our overall approach is to statistically identify the range of volitional movement capabilities, and then apply a robot-applied force vector field intervention that encourages under-expressed movements. We investigated whether explorative training with such customized force fields would improve stroke survivors’ (n = 11) movement patterns in comparison to a control group that trained without forces (n = 11). Force and control groups increased Fugl-Meyer UE scores (average of 1.0 and 1.1, respectively), which is not considered clinically meaningful. Interestingly, participants from both groups demonstrated dramatic increases in their range of velocity during exploration following only six days of training (average increase of 166.4% and 153.7% for the Force and Control group, respectively). While both groups showed evidence of improvement, we also found evidence that customized forces affected learning in a systematic way. When customized forces were active, we observed broader distributions of velocity that were not present in the controls. Second, we found that these changes led to specific changes in unassisted motion. In addition, while the shape of movement distributions changed significantly for both groups, detailed analysis of the velocity distributions revealed that customized forces promoted a greater proportion of favorable changes. Taken together, these results provide encouraging evidence that patient-specific force fields based on individuals’ movement statistics can be used to create ne- movement patterns and shape them in a customized manner. To the best of our knowledge, this paper is the first to directly link engineering assessments of stroke survivors’ exploration movement behaviors to the design of customized robot therapy.
Autors: Zachary A. Wright;Emily Lazzaro;Kelly O. Thielbar;James L. Patton;Felix C. Huang;
Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Publication date: Feb 2018, volume: 26, issue:2, pages: 307 - 323
Publisher: IEEE
 
» Robotic Manipulation of a Rotating Chain
Abstract:
This paper considers the problem of manipulating a uniformly rotating chain: the chain is rotated at a constant angular speed around a fixed axis using a robotic manipulator. Manipulation is quasi-static in the sense that transitions are slow enough for the chain to be always in “rotational equilibrium.” The curve traced by the chain in a rotating plane—its shape function—can be determined by a simple force analysis, yet it possesses a complex multisolutions behavior that is typical of nonlinear systems. We prove that the configuration space of the uniformly rotating chain is homeomorphic to a two-dimensional surface embedded in . Using that representation, we devise a manipulation strategy for transiting between different rotation modes in a stable and controlled manner. We demonstrate the strategy on a physical robotic arm manipulating a rotating chain. Finally, we discuss how the ideas developed here might find fruitful applications in the study of other flexible objects, such as in circular aerial manipulation with UAVs.
Autors: Hung Pham;Quang-Cuong Pham;
Appeared in: IEEE Transactions on Robotics
Publication date: Feb 2018, volume: 34, issue:1, pages: 139 - 150
Publisher: IEEE
 
» Robust Calculation of the Modes in Parabolic Cylinder Metallic Waveguides by Means of a Root-Finding Method for Bivariate Functions
Abstract:
This paper addresses the robust mode computation of the metallic hollow cylindrical waveguide with parabolic contour. Although this waveguide can be solved by separation of variables, it has not been fully characterized in a systematic way in the past. This is not only due to its challenging manufacture, which nowadays can be addressed by modern techniques, but also because of its more complex resolution, involving root finding in a pair of coupled functions with two variables. In order to solve this system, this paper proposes the use of a recently published algorithm for bivariate problems, which is applied for the first time to waveguide mode computation. The method, properly combined with the even and odd Taylor functions, allows obtaining the modes in a systematic and robust way, avoiding, in comparison with previous works, graphical means and the use of starting points from which to iterate. All the modal solutions for symmetrical and asymmetrical cases are solved at once over a wide domain of search with proven high accuracy (relative difference with respect to results from a finite-element method in the order of for more than 1600 modes).
Autors: Ana Morán-López;Juan Córcoles;Jorge A. Ruiz-Cruz;José R. Montejo-Garai;Jesús M. Rebollar;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Feb 2018, volume: 66, issue:2, pages: 623 - 632
Publisher: IEEE
 
» Robust Fault-Tolerant Tracking Control for Spacecraft Proximity Operations Using Time-Varying Sliding Mode
Abstract:
The capture of a free-floating tumbling object using an autonomous vehicle is a key technology for many future orbital missions. Spacecraft proximity operations will play an important role in guaranteeing the success of such missions. In this paper, we technically propose a tracking control scheme for proximity operations between a target and a pursuer spacecraft that ensures accurate relative position tracking as well as attitude synchronization. Specifically, an integrated six degrees of freedom dynamics model is first established to describe the relative motion of the pursuer with respect to the target. Then, a robust fault-tolerant controller is derived by combining the sliding mode control and the adaptive technique. The designed controller is proved to be not only robust against unexpected disturbances and adaptive to unknown and uncertain mass/inertia properties of the pursuer, but also able to accommodate a large class of actuator faults. In particular, by incorporating a novel time-varying forcing function into the sliding dynamics, the proposed control algorithm is able to guarantee the finite-time convergence of the translational and rotational tracking errors, and the convergence time as an explicit parameter can be assigned a priori by the designers. Furthermore, a theoretical analysis is also presented to assess the fault tolerance ability of the designed controller. Finally, numerous examples are carried out to evaluate the effectiveness and demonstrate the benefits of the overall control approach.
Autors: Qinglei Hu;Xiaodong Shao;Wen-Hua Chen;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 2 - 17
Publisher: IEEE
 
» Robust Features of SOSMC Guides in Quality Characterization of Tank Circuit in Air-Cooled Induction Cap Sealing
Abstract:
Induction cap sealers are actively controlled passive component dominant industrial power control equipment. In series resonant inverter-fed air-cooled induction sap sealer, the major part of power loss takes place in high-current passive tank circuit. To enable power transfer to mobile aluminum foil as and when needed, the tank circuit remains energized at rated current. Efficient power delivery to load needs minimum power loss in them. Litz-wire-based air-cooled system, to a large extent, meets this criterion. Further improved performance depends on optimal choice of passive components in the tank circuit. In addition to that, the quality and reliability of the controller depend on electrical and thermal stresses in each of them. At no load, the poor damping factor of litz-wire-based tank circuit tends to generate oscillatory current envelope resulting in increased power loss in tank circuit, as well as in increase e in voltage stress in resonant capacitor. Robust second-order sliding mode control is able to eliminate those problems. This paper further elaborates that the robust power control feature of second-order sliding mode control could uniquely be used to qualitatively differentiate among possible alternates of each constituent member of tank circuit.
Autors: Arun Kumar Paul;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 755 - 763
Publisher: IEEE
 
» Robust Fuzzy Tracking Control of Flexible Spacecraft via a T–S Fuzzy Model
Abstract:
This paper presents a robust fuzzy tracking controller for position and attitude control, and for vibration suppression in a flexible spacecraft. The robust fuzzy controller guarantees tracking control performance while satisfying the actuators’ amplitude constraints. The design problem of the fuzzy tracking controller is formulated in terms of linear matrix inequalities. The stability, performance, and robustness of the proposed fuzzy controller are examined and compared with a baseline nonlinear controller such as the model-reference adaptive controller with -modification via numerical simulations.
Autors: Chokri Sendi;Mohammad A. Ayoubi;
Appeared in: IEEE Transactions on Aerospace and Electronic Systems
Publication date: Feb 2018, volume: 54, issue:1, pages: 170 - 179
Publisher: IEEE
 
» Robust Interpolation of DEMs From Lidar-Derived Elevation Data
Abstract:
Light detection and ranging (lidar)-derived elevation data are commonly subjected to outliers due to the boundaries of occlusions, physical imperfections of sensors, and surface reflectance. Outliers have a serious negative effect on the accuracy of digital elevation models (DEMs). To decrease the impact of outliers on DEM construction, we propose a robust interpolation algorithm of multiquadric (MQ) based on a regularized least absolute deviation (LAD) technique. The objective function of the proposed method includes a regularization-based smoothing term and an LAD-based fitting term, respectively, used to smooth noisy samples and resist the influence of outliers. To solve the objective function of the proposed method, we develop a simple scheme based on the split-Bregman iteration algorithm. Results from simulated data sets indicate that when sample points are noisy or contaminated by outliers, the proposed method is more accurate than the classical MQ and two recently developed robust algorithms of MQ for surface modeling. Real-world examples of interpolating 1 private and 11 publicly available airborne lidar-derived data sets demonstrate that the proposed method averagely produces better results than two promising interpolation methods including regularized spline with tension (RST) and gridded data-based robust thin plate spline (RTPS). Specifically, the image of RTPS is too smooth to retain terrain details. Although RST can keep subtle terrain features, it is distorted by some misclassified object points (i.e., pseudooutliers). The proposed method obtains a good tradeoff between resisting the effect of outliers and preserving terrain features. Overall, the proposed method can be considered as an alternative for interpolating lidar-derived data sets potentially including outliers.
Autors: Chuanfa Chen;Yanyan Li;Na Zhao;Changqing Yan;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Feb 2018, volume: 56, issue:2, pages: 1059 - 1068
Publisher: IEEE
 
» Robust Long-Term Predictive Adaptive Video Streaming Under Wireless Network Uncertainties
Abstract:
Recent research on predictive video delivery promised optimal resource utilization and quality of service (QoS) satisfaction to both dynamic adaptive streaming over HTTP (DASH) providers and mobile users. These gains were attained while presuming an idealistic environment with perfect predictions. Thus, a robust QoS-aware predictive-DASH (P-DASH) is of paramount importance to handling the practical uncertainty implied in predicted information. In this paper, we propose a stochastic QoS-aware robust predictive-DASH (RP-DASH) scheme over future wireless networks that takes into account imperfect rate predictions. The objective is to achieve long-term quality fairness among the DASH users while capping the probability of service degradation by an operator predefined level. A deterministic formulation is then obtained using the scenario approximation, which adopts the probability density function (PDF) of predicted rates. A linear conservative approximation is introduced to provide an NP-complete formulation, which can be optimized by commercial solvers. Since exact PDF might not be available, Gaussian approximation is adopted by the introduced scheme to provide a closed form less complexity formulation. To support real-time implementations, a guided heuristic algorithm is devised to obtain near-optimal resource allocations and quality selections, while satisfying the predefined QoS level. Previous non-robust P-DASH schemes are evaluated in this paper, while considering typical error models in predicted rates. Such schemes resulted in increased QoS and the quality of experience degradations with the network load, which was avoided by the introduced RP-DASH. Results further revealed the ability of RP-DASH to reach optimal and fair QoS satisfactions.
Autors: Ramy Atawia;Hossam S. Hassanein;Aboelmagd Noureldin;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Feb 2018, volume: 17, issue:2, pages: 1374 - 1388
Publisher: IEEE
 
» Robust Multicontrast MRI Spleen Segmentation for Splenomegaly Using Multi-Atlas Segmentation
Abstract:
Objective: Magnetic resonance imaging (MRI) is an essential imaging modality in noninvasive splenomegaly diagnosis. However, it is challenging to achieve spleen volume measurement from three-dimensional MRI given the diverse structural variations of human abdomens as well as the wide variety of clinical MRI acquisition schemes. Multi-atlas segmentation (MAS) approaches have been widely used and validated to handle heterogeneous anatomical scenarios. In this paper, we propose to use MAS for clinical MRI spleen segmentation for splenomegaly. Methods: First, an automated segmentation method using the selective and iterative method for performance level estimation (SIMPLE) atlas selection is used to address the concerns of inhomogeneity for clinical splenomegaly MRI. Then, to further control outliers, semiautomated craniocaudal spleen length-based SIMPLE atlas selection (L-SIMPLE) is proposed to integrate a spatial prior in a Bayesian fashion and guide iterative atlas selection. Last, a graph cuts refinement is employed to achieve the final segmentation from the probability maps from MAS. Results: A clinical cohort of 55 MRI volumes (28 T1 weighted and 27 T2 weighted) was used to evaluate both automated and semiautomated methods. Conclusion: The results demonstrated that both methods achieved median Dice , and outliers were alleviated by the L-SIMPLE (≍1 min manual efforts per scan), which achieved 0.97 Pearson correlation of volume measurements with the manual segmentation. Significance: In this paper, spleen segmentation on MRI splenomegaly using MAS has been performed.
Autors: Yuankai Huo;Jiaqi Liu;Zhoubing Xu;Robert L. Harrigan;Albert Assad;Richard G. Abramson;Bennett A. Landman;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Feb 2018, volume: 65, issue:2, pages: 336 - 343
Publisher: IEEE
 
» Robust Nonnegative Sparse Recovery and the Nullspace Property of 0/1 Measurements
Abstract:
We investigate recovery of nonnegative vectors from non-adaptive compressive measurements in the presence of noise of unknown power. In the absence of noise, existing results in the literature identify properties of the measurement that assure uniqueness in the non-negative orthant. By linking such uniqueness results to nullspace properties, we deduce uniform and robust compressed sensing guarantees for nonnegative least squares. No -regularization is required. As an important proof of principle, we establish that random i.i.d. 0/1-valued Bernoulli matrices obey the required conditions with overwhelming probability provided that . We achieve this by establishing the robust nullspace property for random 0/1-matrices—a novel result in its own right. Our analysis is motivated by applications in wireless network activity detection.
Autors: Richard Kueng;Peter Jung;
Appeared in: IEEE Transactions on Information Theory
Publication date: Feb 2018, volume: 64, issue:2, pages: 689 - 703
Publisher: IEEE
 
» Robust Relay Beamforming Against Jamming Attack
Abstract:
In this letter, we surpass the jamming effect and also estimate the jamming channel state information by using the Kalman filtering approach. Furthermore, we design a closed-form beamforming weight for maximizing the achievable rate subject to the condition that the total relays power transmission would be below a predefined threshold level, which is formulated as a quadratically constrained quadratic program. Simulation results show the efficient performance of the proposed method for different destruction powers of the jammer by achieving the Cramér–Rao lower bound.
Autors: Mohammad Amin Maleki Sadr;Mahmoud Ahmadian Attari;Rouhollah Amiri;
Appeared in: IEEE Communications Letters
Publication date: Feb 2018, volume: 22, issue:2, pages: 312 - 315
Publisher: IEEE
 
» Robust Stability Analysis and State Feedback Synthesis for Discrete-Time Systems Characterized by Random Polytopes
Abstract:
This paper deals with discrete-time linear systems whose state transition is determined by a sequence of random matrices having uncertain distributions. In representing random matrices with uncertain distributions, we use random polytopes whose vertices are random matrices with given fixed distributions. For such systems characterized by random polytopes, we first tackle a problem of analyzing robust second-moment exponential stability. In particular, we show a linear-matrix-inequality-based robust stability condition that can be solved through sample-based evaluation of the associated expectations. The confidence level for such sample-based analysis is ensured by the central limit theorem. Then, we extend the results about analysis toward robust stabilization state feedback synthesis in such a way that the confidence level arguments can be facilitated. We also provide numerical examples illustrating our analysis and synthesis framework.
Autors: Yohei Hosoe;Tomomichi Hagiwara;Dimitri Peaucelle;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Feb 2018, volume: 63, issue:2, pages: 556 - 562
Publisher: IEEE
 
» Robust Update Algorithms for Zero-Forcing Detection in Uplink Large-Scale MIMO Systems
Abstract:
A zero-forcing (ZF) detector is proposed for the uplink channel of large-scale multiple-input-multiple-output systems based on the URV decomposition of the channel matrix. Two efficient algorithms are also proposed for updating and downdating the channel decomposition matrices upon a user’s arrival or exit of the cell, respectively, which avoids re-calculating the URV decomposition. Specifically, the decomposition is updated through the Gram–Schmidt procedure when a user equipment (UE) joins the cell, and is downdated through a set of Givens rotations when a UE leaves the cell. The computational complexity of the proposed detector (referred to as the URV-ZF detector) is evaluated and compared with that of existing methods. It is shown through numerical studies that the URV-ZF detector achieves a lower bit error rate than existing schemes with a slight increase in the computational complexity.
Autors: Chao-Yi Wu;Wan-Jen Huang;Wei-Ho Chung;
Appeared in: IEEE Communications Letters
Publication date: Feb 2018, volume: 22, issue:2, pages: 424 - 427
Publisher: IEEE
 
» Robust Voltage Control of Floating Interleaved Boost Converter for Fuel Cell Systems
Abstract:
In this paper, a robust voltage control is designed for a floating interleaved boost converter with high voltage gain. The proposed controller has an inner loop based on super-twisting sliding mode algorithm, which has continuous control signal and the sliding surface is defined for the inductor current. The reference current value is generated by active disturbance rejection control (ADRC) algorithm in the outer loop, based on the output voltage error. The stability of the sliding mode inner loop and the ADRC outer loop are proven using Lyapunov stability theorem and Routh–Hurwitz criteria, respectively. The robustness of the proposed controller is analyzed in depth, and validated by the simulations and experimental results obtained with a 100 W prototype converter.
Autors: Yigeng Huangfu;Shengrong Zhuo;Fuxi Chen;Shengzhao Pang;Dongdong Zhao;Fei Gao;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Feb 2018, volume: 54, issue:1, pages: 665 - 674
Publisher: IEEE
 
» Role of W in W/Ni Bilayer Ohmic Contact to n-Type 4H-SiC From the Perspective of Device Applications
Abstract:
Ohmic contacts to n-type 4H-SiC using Ni layer and W/Ni bilayer were investigated and compared. The phase composition, electronic states, and carbon structural evolution of the contact layer were analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. The surface roughness and cross-sectional morphology were characterized by atomic force microscopy and high-resolution transmission electron microscopy. The Keithley 4200-SCS semiconductor parameter analyzer was used to measure the current–voltage curves of the contacts. The specific contact resistance was calculated based on the circular transmission line model. is cm2 for W/Ni/SiC and cm2 for Ni/SiC. Ni2Si with minor W substitution and tungsten carbide with minor Ni substitution were identified as the dominant phases for W/Ni/SiC after annealed. The contact surface morphology is improved, and the content of free carbon and the quantity of voids at the interface are reduced when W is introduced into Ni/SiC. The wire bonding is easy to carry out and the thermal stability of ohmic contact is greatly enhanced. From the perspective of device applications, W/Ni bilayer ohmic contact to n-type 4H-SiC is very competitive.
Autors: Shu-Yue Jiang;Xing-Yue Li;Zhi-Zhan Chen;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Feb 2018, volume: 65, issue:2, pages: 641 - 647
Publisher: IEEE
 
» Room Temperature Fabrication of High Quality ZrO2 Dielectric Films for High Performance Flexible Organic Transistor Applications
Abstract:
By using low-cost solution process and ultraviolet (UV) irradiation, we successfully fabricated high-quality ZrO2 films at room temperature. The ZrO2 films obtained with 1-h UV curing showed a very low leakage current ( A/cm2 at −3 V), a high breakdown electric field 7.9 MV/cm, a high bandgap (6.13 eV), and a high dielectric constant (17.8). The organic thin-film transistor made by solution-processed ZrO2 gate dielectric shows a greatly reduced operation voltage of 4 V, and a high drain current on/off ratio of . Furthermore, we also clarified the electronic structures of ZrO2 films with UV cured or thermal annealing. This letter demonstrated that solution-processable ZrO2 film is promising for applications in future low power consumption electronic devices.
Autors: Yanfen Gong;Kai Zhao;Longsen Yan;Weiyao Wei;Cheng Yang;Honglong Ning;Sujuan Wu;Jinwei Gao;Guofu Zhou;Xubing Lu;J.-M. Liu;
Appeared in: IEEE Electron Device Letters
Publication date: Feb 2018, volume: 39, issue:2, pages: 280 - 283
Publisher: IEEE
 

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