Electrical and Electronics Engineering publications abstract of: 10-2017 sorted by title, page: 13

» Level Set Segmentation Algorithm for High-Resolution Polarimetric SAR Images Based on a Heterogeneous Clutter Model
Abstract:
In this paper, a heterogeneous clutter model named distribution is introduced into the level set method for segmentation of high-resolution polarimetric synthetic aperture radar (PolSAR) images. Level set methods are robust and effective techniques for segmentation. However, traditional level set methods for PolSAR data are based on the complex Wishart distribution, which is not an applicable model to high-resolution PolSAR images and heterogeneous regions such as forest and urban areas. The distribution is proved to be a highly flexible model for multilook PolSAR data, which is based on the product model with a generalized-gamma-distributed texture component. The -model-based level set segmentation method is assessed using C-band, X-band, and L-band PolSAR data acquired by RADARSAT-2, TerraSAR-X, and ESAR sensors, respectively. Experimental results show that the -distribution model has a better capacity for characterizing high-resolution PolSAR data, especially for extremely heterogeneous regions. Compared with the Wishart-model-based and Kummer-U-model-based level set methods and Markov random field based methods, it is observed that the proposed level set algorithm can obtain more precise segmentation results.
Autors: Ruijin Jin;Junjun Yin;Wei Zhou;Jian Yang;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Oct 2017, volume: 10, issue:10, pages: 4565 - 4579
Publisher: IEEE
 
» Leveraging nMOS Negative Differential Resistance for Low Power, High Reliability Magnetic Memory
Abstract:
We propose, demonstrate, and assess a nontunneling-based nMOS voltage-controlled negative differential resistance (V-NDR) concept for overcoming the intrinsic efficiency and reliability shortcomings of magnetic random access memory memories (MRAM). Using nMOS V-NDR circuits in series with MRAM tunnel junctions, we experimentally observe 40 times reduction in current during switching, enabling write termination and read margin amplification. Large scale Monte Carlo simulations also show 5X improvement in write energy savings and demonstrate the robustness of the scheme against device variability.
Autors: Shaodi Wang;Andrew Pan;Cecile Grezes;Pedram Khalili Amiri;Kang L. Wang;Chi On Chui;Puneet Gupta;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Oct 2017, volume: 64, issue:10, pages: 4084 - 4090
Publisher: IEEE
 
» Leveraging the Survivable All-Optical WDM Network Design With Network Coding Assignment
Abstract:
This letter investigates a novel use of network coding (NC) in 1 + 1 protection for transparent wavelength-division multiplexing networks by utilizing a cost-effective all-optical XOR encoder/decoder. In applying this scheme, we introduce a new problem, called routing, wavelength, and NC assignment, and formulate it as the integer linear programming model, aiming at maximizing the network throughput under constrained bandwidth capacity. We evaluate our proposal on the realistic topology, COST239, with all-to-one traffic setting. The numerical results on studied case show that the our NC-based approach could support up to 30% traffic more than the conventional 1 + 1 protection.
Autors: Dao Thanh Hai;
Appeared in: IEEE Communications Letters
Publication date: Oct 2017, volume: 21, issue:10, pages: 2190 - 2193
Publisher: IEEE
 
» Lidar System Architectures and Circuits
Abstract:
3D imaging technologies are applied in numerous areas, including self-driving cars, drones, and robots, and in advanced industrial, medical, scientific, and consumer applications. 3D imaging is usually accomplished by finding the distance to multiple points on an object or in a scene, and then creating a point cloud of those range measurements. Different methods can be used for the ranging. Some of these methods, such as stereovision, rely on processing 2D images. Other techniques estimate the distance more directly by measuring the round-trip delay of an ultrasonic or electromagnetic wave to the object. Ultrasonic waves suffer large losses in air and cannot reach distances beyond a few meters. Radars and lidars use electromagnetic waves in radio and optical spectra, respectively. The shorter wavelengths of the optical waves compared to the radio frequency waves translates into better resolution, and a more favorable choice for 3D imaging. The integration of lidars on electronic and photonic chips can lower their cost, size, and power consumption, making them affordable and accessible to all the abovementioned applications. This review article explains different lidar aspects and design choices, such as optical modulation and detection techniques, and point cloud generation by means of beam-steering or flashing an entire scene. Popular lidar architectures and circuits are presented, and the superiority of the FMCW lidar is discussed in terms of range resolution, receiver sensitivity, and compatibility with emerging technologies. At the end, an electronic-photonic integrated circuit for a micro-imaging FMCW lidar is presented as an example.
Autors: Behnam Behroozpour;Phillip A. M. Sandborn;Ming C. Wu;Bernhard E. Boser;
Appeared in: IEEE Communications Magazine
Publication date: Oct 2017, volume: 55, issue:10, pages: 135 - 142
Publisher: IEEE
 
» Light Field Compression With Homography-Based Low-Rank Approximation
Abstract:
This paper describes a light field compression scheme based on a novel homography-based low-rank approximation method called HLRA. The HLRA method jointly searches for the set of homographies best aligning the light field views and for the low-rank approximation matrices. The light field views are aligned using either one global homography or multiple homographies depending on how much the disparity across views varies from one depth plane to the other. The light field low-rank representation is then compressed using high efficiency video coding (HEVC). The best pair of rank and quantization parameters of the coding scheme, for a given target bit rate, is predicted with a model defined as a function of light field disparity and texture features. The results are compared with those obtained by directly applying HEVC on the light field views restructured as a pseudovideo sequence. The experiments using different datasets show substantial peak signal to noise ratio (PSNR)-rate gain of our compression algorithm, as well as the accuracy of the proposed parameter prediction model, especially for real light fields. A scalable extension of the coding scheme is finally proposed.
Autors: Xiaoran Jiang;Mikaël Le Pendu;Reuben A. Farrugia;Christine Guillemot;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Oct 2017, volume: 11, issue:7, pages: 1132 - 1145
Publisher: IEEE
 
» Light Field Image Coding Using High-Order Intrablock Prediction
Abstract:
This paper proposes a two-stage high-order intrablock prediction method for light field image coding. This method exploits the spatial redundancy in lenslet light field images by predicting each image block, through a geometric transformation applied to a region of the causal encoded area. Light field images comprise an array of microimages that are related by complex geometric transformations that cannot be efficiently compensated by state-of-the-art image coding techniques, which are usually based on low-order translational prediction models. The two-stage nature of the proposed method allows us to choose the order of the prediction model most suitable for each block, ranging from pure translations to projective or bilinear transformations, optimized according to an appropriate rate-distortion criterion. The proposed higher order intrablock prediction approach was integrated into a high efficiency video coding (HEVC) codec and evaluated for both unfocused and focused light field camera models, using different resolutions and microlens arrays. Experimental results show consistent bitrate savings, which can go up to 12.62%, when compared to a lower order intrablock prediction solution and 49.82% when compared to HEVC still picture coding.
Autors: Ricardo J. S. Monteiro;Paulo J. L. Nunes;Nuno M. M. Rodrigues;Sérgio M. M. Faria;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Oct 2017, volume: 11, issue:7, pages: 1120 - 1131
Publisher: IEEE
 
» Light Field Image Processing: An Overview
Abstract:
Light field imaging has emerged as a technology allowing to capture richer visual information from our world. As opposed to traditional photography, which captures a 2D projection of the light in the scene integrating the angular domain, light fields collect radiance from rays in all directions, demultiplexing the angular information lost in conventional photography. On the one hand, this higher dimensional representation of visual data offers powerful capabilities for scene understanding, and substantially improves the performance of traditional computer vision problems such as depth sensing, post-capture refocusing, segmentation, video stabilization, material classification, etc. On the other hand, the high-dimensionality of light fields also brings up new challenges in terms of data capture, data compression, content editing, and display. Taking these two elements together, research in light field image processing has become increasingly popular in the computer vision, computer graphics, and signal processing communities. In this paper, we present a comprehensive overview and discussion of research in this field over the past 20 years. We focus on all aspects of light field image processing, including basic light field representation and theory, acquisition, super-resolution, depth estimation, compression, editing, processing algorithms for light field display, and computer vision applications of light field data.
Autors: Gaochang Wu;Belen Masia;Adrian Jarabo;Yuchen Zhang;Liangyong Wang;Qionghai Dai;Tianyou Chai;Yebin Liu;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Oct 2017, volume: 11, issue:7, pages: 926 - 954
Publisher: IEEE
 
» Line Detection as an Inverse Problem: Application to Lung Ultrasound Imaging
Abstract:
This paper presents a novel method for line restoration in speckle images. We address this as a sparse estimation problem using both convex and non-convex optimization techniques based on the Radon transform and sparsity regularization. This breaks into subproblems, which are solved using the alternating direction method of multipliers, thereby achieving line detection and deconvolution simultaneously. We include an additional deblurring step in the Radon domain via a total variation blind deconvolution to enhance line visualization and to improve line recognition. We evaluate our approach on a real clinical application: the identification of B-lines in lung ultrasound images. Thus, an automatic B-line identification method is proposed, using a simple local maxima technique in the Radon transform domain, associated with known clinical definitions of line artefacts. Using all initially detected lines as a starting point, our approach then differentiates between B-lines and other lines of no clinical significance, including Z-lines and A-lines. We evaluated our techniques using as ground truth lines identified visually by clinical experts. The proposed approach achieves the best B-line detection performance as measured by the F score when a non-convex regularization is employed for both line detection and deconvolution. The F scores as well as the receiver operating characteristic (ROC) curves show that the proposed approach outperforms the state-of-the-art methods with improvements in B-line detection performance of 54%, 40%, and 33% for , , and ,- respectively, and of 24% based on ROC curve evaluations.
Autors: Nantheera Anantrasirichai;Wesley Hayes;Marco Allinovi;David Bull;Alin Achim;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Oct 2017, volume: 36, issue:10, pages: 2045 - 2056
Publisher: IEEE
 
» Linearity Enhancement of a Fully Integrated 6-GHz GaN Power Amplifier
Abstract:
A large-signal nonlinearity compensation technique is developed to improve the linearity of RF GaN power amplifiers. The design of a high power amplifier employing both common-source (CS) and common-gate (CG) GaN high-electron mobility transistors is presented for the IEEE 802.11p standard. The power amplifier is fabricated in 0.25- GaN-on-SiC technology and occupies 1.7 mm mm. The measurements show that 35-dBm output 1-dB compression point (OP1 dB) is obtained with 39-dBm OIP3 for two-tone intermodulation distortion testing. It also achieves 31% drain efficiency at 28.8-dBm output power with 10-V supply voltage considering a more than 6-dB back-off for orthogonal frequency division multiplexing-modulated signals. Linearity enhancement by means of the proposed CS–CG configuration is demonstrated in a fully integrated GaN power amplifier at 6 GHz.
Autors: Pilsoon Choi;Ujwal Radhakrishna;Chirn Chye Boon;Li-Shiuan Peh;Dimitri Antoniadis;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Oct 2017, volume: 27, issue:10, pages: 927 - 929
Publisher: IEEE
 
» Linearizing Discrete-Time Hybrid Systems
Abstract:
Model-based design approaches for embedded systems aim at generating correct-by-construction control software, guaranteeing that the closed-loop system (controller and plant) meets given system level formal specifications. This technical note addresses control synthesis for safety and reachability properties of possibly nonlinear discrete-time hybrid systems. By means of a syntactical transformations that requires nonlinear terms to be Lipschitz continuous functions, we overapproximate nonlinear dynamics with a linear system whose controllers are guaranteed to be controllers of the original system. We evaluate performance of our approach on meaningful control synthesis benchmarks, also comparing it to a state-of-the-art tool.
Autors: Vadim Alimguzhin;Federico Mari;Igor Melatti;Ivano Salvo;Enrico Tronci;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Oct 2017, volume: 62, issue:10, pages: 5357 - 5364
Publisher: IEEE
 
» List of Reviewers for 2016/2017
Abstract:
The IEEE Transactions on Automation Science and Engineering (T-ASE) wishes to thank the 987 reviewers over the past year who have performed an essential role in maintaining the quality of this publication. T-ASE strives for the 90–90 standard, i.e., 90% of papers should be reviewed within 90 days of submission. The review process starts when the Editor-in-Chief assigns the paper to an Editor, who assigns it to an Associate Editor (AE). The AE then obtains confirmation from 3–5 reviewers, carefully studies the results, and makes a recommendation to the Editor, who then makes a decision that is reported back to the lead author. This review process is very demanding, especially under the time constraints. We have summarized the process under “Guidelines for T-ASE Editors and AEs for Handling Papers” on our website. I am pleased to report that submissions have steadily increased (over 1000 in 2016) and our Impact Factor is now 3.502, an 16.5% increase over last year. As we strive to increase the quality and impact of the journal, we rely on the hard work of our reviewers and members of the Editorial Board. To those dedicated volunteers, and to anyone who may have been inadvertently omitted from the list below, we extend our sincere appreciation.
Autors: Michael Y. Wang;
Appeared in: IEEE Transactions on Automation Science and Engineering
Publication date: Oct 2017, volume: 14, issue:4, pages: 1793 - 1797
Publisher: IEEE
 
» Lithium-Ion Battery Parameters and State-of-Charge Joint Estimation Based on H-Infinity and Unscented Kalman Filters
Abstract:
Accurate estimation of state-of-charge (SoC) is vital to safe operation and efficient management of lithium-ion batteries. Currently, the existing SoC estimation methods can accurately estimate the SoC in a certain operation condition, but in uncertain operating environments, such as unforeseen road conditions and aging related effects, they may be unreliable or even divergent. This is due to the fact that the characteristics of lithium-ion batteries vary under different operation conditions and the adoption of constant parameters in battery model, which are identified offline, will affect the SoC estimation accuracy. In this paper, the joint SoC estimation method is proposed, where battery model parameters are estimated online using the H-infinity filter, while the SoC are estimated using the unscented Kalman filter. Then, the proposed method is compared with the SoC estimation methods with constant battery model parameters under different dynamic load profiles and operation temperatures. It shows that the proposed joint SoC estimation method possesses high accuracy, fast convergence, excellent robustness and adaptability.
Autors: Quanqing Yu;Rui Xiong;Cheng Lin;Weixiang Shen;Junjun Deng;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Oct 2017, volume: 66, issue:10, pages: 8693 - 8701
Publisher: IEEE
 
» Load Modulation of Harmonically Tuned Amplifiers and Application to Outphasing Systems
Abstract:
Modulation of load impedance is an effective way to maintain efficient power amplifier (PA) operation over high dynamic range modulated signals. For high efficiency, a load modulation approach can be applied to inherently efficient classes of PAs such as those with harmonic tuning: Class J, Class F, and Inverse Class F. This paper presents an analysis of harmonically tuned (HT) amplifiers operating under load modulation conditions, deriving the optimal loading trajectories for these multiple classes of operation. Because these load trajectories are complex, it is then shown—through a series of analysis, simulations, and measurements—that HT amplifiers are better suited for outphasing systems, than conventional amplifiers such as Class B. A design methodology is proposed and validated through design and measurement of a 900-MHz outphasing system, comprising of two Gallium Nitride Class J branch PAs, delivering 44.6 dBm with 75% PAE at saturation, while mantaining PAE above 60% over a 7-dB output power back-off.
Autors: Paolo Enrico de Falco;Prathamesh Pednekar;Konstantinos Mimis;Souheil Ben Smida;Gavin Watkins;Kevin Morris;Taylor Wallis Barton;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Oct 2017, volume: 65, issue:10, pages: 3596 - 3612
Publisher: IEEE
 
» Local Area Radiation Sidelobe Suppression of Reflector Antennas by Embedding Periodic Metallic Elements Along the Edge Boundary
Abstract:
This communication presents a simple and useful technique to suppress the radiation sidelobe levels (SLLs) of reflector antennas by embedding reflecting elements around the edge boundary. Due to the fact that sidelobes mainly arise from the edge diffractions, the reflecting elements can alter the phase distribution of induced currents along the edge boundary, and therefore reduce the sidelobes through the destructive cancellation of fields radiated from these elements. The desired phases are found through the implementation of pattern synthesis technique such as genetic algorithm to optimize the SLLs. This technique of edge current phase alternation may be employed, in conjunction with using a tapered feed radiation to illuminate the reflector, to control both amplitudes and phases of edge currents. Thus, the edge diffraction mechanism may be better controlled to optimize SLLs. In this communication, both resonant and nonresonant types of metallic elements are implemented and compared to illustrate their characteristics of radiations in SLL suppression. This technique is particularly useful to suppress the SLLs within a local angular region. Numerical results based on the method of moment analysis are presented to validate the feasibility.
Autors: Hsi-Tseng Chou;Hsien-Kwei Ho;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Oct 2017, volume: 65, issue:10, pages: 5611 - 5616
Publisher: IEEE
 
» Local Submodularization for Binary Pairwise Energies
Abstract:
Many computer vision problems require optimization of binary non-submodular energies. We propose a general optimization framework based on local submodular approximations (LSA). Unlike standard LP relaxation methods that linearize the whole energy globally, our approach iteratively approximates the energy locally. On the other hand, unlike standard local optimization methods (e.g., gradient descent or projection techniques) we use non-linear submodular approximations and optimize them without leaving the domain of integer solutions. We discuss two specific LSA algorithms based on trust region and auxiliary function principles, LSA-TR and LSA-AUX. The proposed methods obtain state-of-the-art results on a wide range of applications such as binary deconvolution, curvature regularization, inpainting, segmentation with repulsion and two types of shape priors. Finally, we discuss a move-making extension to the LSA-TR approach. While our paper is focused on pairwise energies, our ideas extend to higher-order problems. The code is available online.
Autors: Lena Gorelick;Yuri Boykov;Olga Veksler;Ismail Ben Ayed;Andrew Delong;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Oct 2017, volume: 39, issue:10, pages: 1985 - 1999
Publisher: IEEE
 
» Localization Accuracy Improvement of a Visible Light Positioning System Based on the Linear Illumination of LED Sources
Abstract:
As a new technique of indoor localization, visible light positioning has the advantages of high accuracy and antielectromagnetic interference. Received signal strength (RSS) based visible light positioning method is easy to implement because it requires simple hardware structure. However, in practical scenarios, the actual channel gain does not follow the ideal channel model. Instead of Lambertian channel model, some approximations have to be adopted to describe the relationship between received optical power and distance, and these approximations will cause deviation of positioning calculation. In this paper, an optical antenna based on freeform lens design is proposed to improve the accuracy of RSS-based positioning. With the optical antenna, the luminous intensity distribution is optimized, and the relationship between received optical power and distance becomes a simple linear relationship. Results show that RSS-based positioning system using freeform lens optical antenna can improve the positioning accuracy by 44%. Furthermore, the advantage of the optical antenna we designed for a visible light communication positioning system demonstrated uniformity under different conditions.
Autors: Nan Wu;Lihui Feng;Aiying Yang;
Appeared in: IEEE Photonics Journal
Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 11
Publisher: IEEE
 
» Locally Optimal Inspired Detection in Snapping Shrimp Noise
Abstract:
In this paper, we address the problem of detecting a known signal in snapping shrimp noise. The latter dominates the ambient soundscape at medium-to-high frequencies in warm shallow waters. The noise process is impulsive, exhibits memory and is modeled effectively by stationary -sub-Gaussian noise with memory order (SGN()), which is essentially an impulsive Markov process. Robust detectors have long been used to mitigate the impact of impulsive noise on the performance of digital systems. However, conventional notions of robustness do not assume memory within the noise process. The SGN() model offers a mathematical model to develop robust detectors that also exploit the mutual information between noise samples. Recent works in this area highlight substantial improvement in detection performance over traditional robust methods in snapping shrimp noise. However, implementing such detectors is a challenge as they are parametric and computationally taxing. To achieve more realizable detectors, we derive the locally optimal detector for SGN( ). From it, we introduce the generalized memory-based sign correlator and its variants, all of which offer near-optimal performance in SGN(). The proposed detectors off- r excellent performance in snapping shrimp noise and low computational complexity. These properties make them attractive for use in underwater acoustical systems operating in snapping shrimp noise.
Autors: Ahmed Mahmood;Mandar Chitre;Hari Vishnu;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Oct 2017, volume: 42, issue:4, pages: 1049 - 1062
Publisher: IEEE
 
» Locally Orthogonal Training Design for Cloud-RANs Based on Graph Coloring
Abstract:
We consider training-based channel estimation for a cloud radio access network (CRAN), in which a large amount of remote radio heads and users are randomly scattered over the service area. In this model, assigning orthogonal training sequences to all users will incur a substantial overhead to the overall network, and is even impossible when the number of users is large. Therefore, in this paper, we introduce the notion of local orthogonality, under which the training sequence of a user is orthogonal to those of the other users in its neighborhood. We model the design of locally orthogonal training sequences as a graph coloring problem. Then, based on the theory of random geometric graph, we show that the minimum training length scales in the order of , where is the number of users covered by a CRAN. This implies that the proposed training design yields a scalable solution to sustain the need of large-scale cooperation in CRANs.
Autors: Jianwen Zhang;Xiaojun Yuan;Ying Jun Zhang;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Oct 2017, volume: 16, issue:10, pages: 6426 - 6437
Publisher: IEEE
 
» Location-Assisted Coding for FSO Communication
Abstract:
Recent years have witnessed an explosive growth in the number of wireless devices. This development has fueled much research in wireless access technologies to efficiently use radio frequency spectrum. On the other hand, recent advances in free space optical (FSO) technologies promise a complementary approach to increase wireless capacity. In this paper, we describe WiFO, a hybrid WiFi and FSO high-speed wireless local area network of femtocells that can provide high bit rates while maintaining seamless mobility. Importantly, we introduce a novel location-assisted coding (LAC) technique, based on which, the number of novel rate allocation algorithms is proposed to increase throughput and reduce interference for multiple users in a dense array of overlapped femtocells. Both theoretical analysis and numerical results show orders of magnitude increase in throughput using LAC over existing schemes for various random topologies.
Autors: Duong Nguyen-Huu;Thai Duong;Thinh Nguyen;
Appeared in: IEEE Transactions on Communications
Publication date: Oct 2017, volume: 65, issue:10, pages: 4360 - 4370
Publisher: IEEE
 
» LocDyn: Robust Distributed Localization for Mobile Underwater Networks
Abstract:
How do we self-localize large teams of underwater nodes using only noisy range measurements? How do we do it in a distributed way, and incorporating dynamics into the problem? How do we reject outliers and produce trustworthy position estimates? And what if some of the vehicles can measure angular information? The stringent acoustic communication constraints and accuracy needs of our geophysical survey application demand fast and very accurate localization methods. We address dynamic localization as a MAP estimation problem where the prior encodes kinematic information, and we apply a convex relaxation method that takes advantage of previous estimates at each measurement acquisition step. The resulting LocDyn algorithm is fast: It converges at an optimal rate for first order methods. LocDyn is distributed: There is no fusion center responsible for processing acquired data and the same simple computations are performed at each node. LocDyn is accurate: Numerical experiments attest to about 30% smaller positioning error than a comparable Kalman filter. LocDyn is robust: It rejects outlier noise, while benchmarking methods succumb in terms of positioning error.
Autors: Cláudia Soares;João Gomes;Beatriz Quintino Ferreira;João Paulo Costeira;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Oct 2017, volume: 42, issue:4, pages: 1063 - 1074
Publisher: IEEE
 
» LOMCF: Forwarding and Caching in Named Data Networking Based MANETs
Abstract:
Named data networking (NDN) resolves traditional transmission control protocol/internet protocol (TCP/IP)-based Internet problems (i.e., location dependent, complex usage, scalability, poor resource utilization, etc.) and is considered as an eligible candidate for futuristic Internet paradigm. In NDN-based mobile ad hoc networks (MANETs), the participating nodes are operated in highly dynamic and challengeable environment such as low battery power, channel fluctuations, intermittent connectivity, etc. Due to the broadcast nature of the wireless channel, the NDN-based MANETs highlight severe issues (e.g., packet collisions, flooding, data redundancy, and packet retransmissions), which further degrade network performance. In this paper, to cope with these problems, we have proposed a novel protocol, named location-aware on-demand multipath caching and forwarding for NDN-based MANETs. Performance of the proposed protocol is evaluated by using a simulator called ndnSIM. Extensive experiments along their results show that proposed protocol performs better as compared with the other recent proposed protocols in terms of content retrieval time, Interest retransmissions, and the total number of Interest packets injected, as well as discarded, in the network.
Autors: Rana Asif Rehman;Byung-Seo Kim;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Oct 2017, volume: 66, issue:10, pages: 9350 - 9364
Publisher: IEEE
 
» Long Period Fiber Grating Inscribed in Hollow-Core Photonic Bandgap Fiber for Gas Pressure Sensing
Abstract:
In this paper, we have proposed and experimentally prepared an improved gas pressure sensing device. It is mainly constructed by a short hollow silica tube segment and a CO2-laser-induced long period grating in hollow-core photonic bandgap fiber (HC-PBF). To effectively enhance the interaction between light in the air-core of HC-PBF and external surroundings, thus to achieve the best possible gas pressure sensitivity, a microchannel is introduced in the middle of the hollow silica tube segment with the femtosecond laser processing technique. The corresponding gas pressure experiments demonstrate that the resonant wavelength of the LPFG shows a blue shift up to −1.3 nm/MPa. Moreover, the temperature response sensitivity of this sensor is as low as 5.3 pm/°C and enable it possible as a temperature-insensitive gas pressure measure apparatus.
Autors: Jian Tang;Zhe Zhang;Guolu Yin;Shen Liu;Zhiyong Bai;Zhengyong Li;Mi Deng;Ying Wang;Changrui Liao;Jun He;Wei Jin;Gang-Ding Peng;Yiping Wang;
Appeared in: IEEE Photonics Journal
Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 7
Publisher: IEEE
 
» Long-Range OFDR-Based Distributed Vibration Optical Fiber Sensor by Multicharacteristics of Rayleigh Scattering
Abstract:
We present a long-range optical frequency domain reflectometry (OFDR) based distributed vibration optical fiber sensor (DVOFS) by multicharacteristics of Rayleigh scattering. Comparing with utilizing a single characteristic of Rayleigh scattering, by using multicharacteristics of Rayleigh scattering, two or more simultaneous vibration events in a long sensing range can be detected and located in DVOFS. In a single-ended OFDR-based DVOFS without any optical amplification, we can discriminate two simultaneous vibration events by two different characteristics. One is the local Rayleigh scattering spectra shifts for locating the first vibration event. The other is the “V” shape in Rayleigh scattering signals in the spatial domain for locating the second vibration event. The sensing range of this DVOFS is 92 km and the spatial resolution of locating vibration events is 13 m.
Autors: Zhenyang Ding;Di Yang;Kun Liu;Junfeng Jiang;Yang Du;Bingkun Li;Minghao Shang;Tiegen Liu;
Appeared in: IEEE Photonics Journal
Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 10
Publisher: IEEE
 
» Loop-Free Backpressure Routing Using Link-Reversal Algorithms
Abstract:
The backpressure routing policy is known to be a throughput optimal policy that supports any feasible traffic demand, but may have poor delay performance when packets traverse loops in the network. In this paper, we study loop-free backpressure routing policies that forward packets along directed acyclic graphs (DAGs) to avoid the looping problem. These policies use link reversal algorithms to improve the DAGs in order to support any achievable traffic demand. For a network with a single commodity, we show that a DAG that supports a given traffic demand can be found after a finite number of iterations of the link-reversal process. We use this to develop a joint link-reversal and backpressure routing policy, called the loop free backpressure (LFBP) algorithm. This algorithm forwards packets on the DAG, while the DAG is dynamically updated based on the growth of the queue backlogs. We show by simulations that such a DAG-based policy improves the delay over the classical backpressure routing policy. We also propose a multicommodity version of the LFBP algorithm and via simulation show that its delay performance is better than that of backpressure.
Autors: Anurag Rai;Chih-ping Li;Georgios Paschos;Eytan Modiano;
Appeared in: IEEE/ACM Transactions on Networking
Publication date: Oct 2017, volume: 25, issue:5, pages: 2988 - 3002
Publisher: IEEE
 
» Loss Function Modeling of Efficiency Maps of Electrical Machines
Abstract:
This paper presents a novel approach in the modeling of efficiency maps for electrical machines. It is based on using the sum of terms in the form of kmnTmωn to represent the variation of the stator and rotor copper, iron, and magnet losses with torque and speed. The effect of each term on the shape of the efficiency map is explored. Analysis is performed on the calculated efficiency and loss maps of an induction, an interior permanent magnet, and a surface permanent magnet machine to demonstrate the validity of the approach.
Autors: Amin Mahmoudi;Wen L. Soong;Gianmario Pellegrino;Eric Armando;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Oct 2017, volume: 53, issue:5, pages: 4221 - 4231
Publisher: IEEE
 
» Loss Identification in a Double Rotor Electrical Variable Transmission
Abstract:
An electrical variable transmission (EVT) is an electromagnetic power-split device with two mechanical and two electrical ports. It can be used in hybrid electric vehicles to split the power to the wheels in a part coming from the combustion engine and a part exchanged with the battery. Although crucial for the EVT design and evaluation, no papers are found to give a detailed overview of the different loss components in such a machine and how they can be calculated and measured. In contrast to conventional electrical machines, this machine has more degrees of freedom, which can be exploited to measure the different loss contributions separately. This paper proposes a methodology to identify and measure the different loss components in this kind of machines. The proposed method is able to identify the iron losses in stator and inner rotor, the copper losses, bearing losses, and slip ring friction losses separately. To this end, measurements of both torque and speed sensors in different operating points are combined. The methods are applied to identify the different loss contributions in a prototype permanent magnet assisted EVT, both in no-load operation as under load where its functionality as power-split device is evaluated.
Autors: Joachim Druant;Hendrik Vansompel;Frederik De Belie;Peter Sergeant;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Oct 2017, volume: 64, issue:10, pages: 7731 - 7740
Publisher: IEEE
 
» Loss of low-frequency data in on- line frequency response analysis of transformers
Abstract:
Power transformers are a key component of the electricity supply grid. Monitoring and assessment of their condition has always been of great concern [1]. In critical situations, transformer failures can cause irreversible damage and considerable financial loss to the grid stakeholders or even the end-users [2], [3]. In this regard, mechanical defects are considered a major problem in distribution and power transformers [4]. Consequently various diagnostic techniques have been developed to identify transformer mechanical defects and winding deformation.
Autors: Mehdi Bagheri;Svyatoslav Nezhivenko;B. T. Phung;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Oct 2017, volume: 33, issue:5, pages: 32 - 39
Publisher: IEEE
 
» Lossless Compression Decoders for Bitstreams and Software Binaries Based on High-Level Synthesis
Abstract:
As the density of field-programmable gate arrays continues to increase, the size of configuration bitstreams grows accordingly. Compression techniques can reduce memory size and save external memory bandwidth. To accelerate the configuration process and reduce the software startup time, four open-source lossless compression decoders developed using high-level synthesis techniques are presented. Moreover, in order to balance the objectives of compression ratio, decompression throughput, and hardware resource overhead, various improvements and optimizations are proposed. Full bitstreams and software binaries have been collected as a benchmark, and 33 partial bitstreams have also been developed and integrated into the benchmark. Evaluations of the synthesizable compression decoders are demonstrated on a Xilinx ZC706 board, showing higher decompression throughput than those of the existing lossless compression decoders using our benchmark. The proposed decoders can reduce software startup time by up to 31.23% in embedded systems and 69.83% reduction of reconfiguration time for partial reconfigurable systems.
Autors: Jian Yan;Junqi Yuan;Philip H. W. Leong;Wayne Luk;Lingli Wang;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Oct 2017, volume: 25, issue:10, pages: 2842 - 2855
Publisher: IEEE
 
» Lossless In-Network Processing and Its Routing Design in Wireless Sensor Networks
Abstract:
In many domain-specific monitoring applications of wireless sensor networks (WSNs), such as structural health monitoring, volcano tomography, and machine diagnosis, the raw data in WSNs are required to be losslessly gathered to the sink, where a specialized centralized algorithm is then executed to extract some global features or model parameters. To reduce the large raw data transmission, in-network processing is usually employed. However, different from most existing in-network processing works that pre-assume some common computation/aggregation functions, in-network processing of a given centralized algorithm requires exact partitioning of the algorithm first and then appropriately assigning the partitioned computations into WSNs. We call this lossless in-network processing, which has not been studied much. Lossless in-network processing raises two questions: 1) what pattern should a centralized algorithm be partitioned into so that the partitioned computations can be flexibly assigned into a WSN with arbitrary topology? and 2) for each partition pattern, how should efficient routing for the resource-limited sensor nodes be designed? These two questions can be referred to as a topology-constrained computation partition problem and a computation-constrained routing design problem, respectively. In this paper, we first introduce some general patterns on the topology-constrained computation partition. Then, with the computation constraints in the patterns, we present a series of novel routing schemes customized for different cases of computation results. The work in this paper can also serve as a guideline for distributed computing of big data, where the data spreads in a large network.
Autors: Peng Guo;Xuefeng Liu;Jiannong Cao;Shaojie Tang;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Oct 2017, volume: 16, issue:10, pages: 6528 - 6542
Publisher: IEEE
 
» Lossless In-Network Processing in WSNs for Domain-Specific Monitoring Applications
Abstract:
Internet of things (IOT) is emerging as sensing paradigms in many domain-specific monitoring applications in smart cities, such as structural health monitoring (SHM) and smart grid monitoring. Due to the large size of the monitoring objects (e.g., civil structure or the power grid), plenty of sensors need to be deployed and organized to be a large scale of multihop wireless sensor networks (WSNs), which tends to have quite high transmission cost. In-network processing is an efficient way to reduce the transmission cost in WSNs. However, implementing in-network processing for above domain-specific monitoring usually requires to losslessly distribute a dedicate domain-specific algorithm into WSNs, which is much different from most existing in-network processing works. This paper conducts a case study of a classic centralized SHM algorithm, i.e., eigensystem realization algorithm (ERA), and shows how to losslessly and optimally in-network process ERA, especially the typical feature extraction method, i.e., that is singular value decomposition (SVD) therein, in a WSN. Based on whether the intermediate data can be processed together or not by sensor nodes, we respectively implement tree-based in-network processing of SVD and chain-based in-network processing of SVD in WSNs. We prove that using an appropriate shallow light tree as routes for tree-based in-network processing of SVD, can achieve the approximation ratio (in terms of transmission cost), while for the chain-based in-network processing of SVD, we design two efficient heuristic algorithms for searching the optimal routes. Extensive simulation results validate the efficiency of these proposed schemes that are customized for SVD-based IOT applications.
Autors: Peng Guo;Jiannong Cao;Xuefeng Liu;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Oct 2017, volume: 13, issue:5, pages: 2130 - 2139
Publisher: IEEE
 
» Lotfi A. Zadeh In Memoriam
Abstract:
Autors: Piero P. Bonissone;Enrique H. Ruspini;
Appeared in: IEEE Transactions on Fuzzy Systems
Publication date: Oct 2017, volume: 25, issue:5, pages: 1021 - 1022
Publisher: IEEE
 
» Low Complexity Resource Allocation for Massive Carrier Aggregation
Abstract:
Optimal resource allocation (RA) in massive carrier aggregation scenarios is a challenging combinatorial optimization problem whose dimension is proportional to the number of users, component carriers (CCs), and OFDMA resource blocks per CC. Toward scalable, near-optimal RA in massive CA settings, an iterative RA algorithm is proposed for joint assignment of CCs and OFDMA resource blocks to users. The algorithm is based on the principle of successive geometric programming approximations and has a complexity that scales only linearly with the problem dimension. Although its derivation is based on a relaxed formulation of the RA problem, the algorithm is shown to converge to integer-valued RA variables with probability 1 under mild assumptions on the distribution of user utilities. Simulations demonstrate improved performance of the proposed algorithm compared to commonly considered heuristic RA procedures of comparable complexity.
Autors: Stelios Stefanatos;Fotis Foukalas;Theodoros A. Tsiftsis;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Oct 2017, volume: 66, issue:10, pages: 9614 - 9619
Publisher: IEEE
 
» Low Correlation Sequences From Linear Combinations of Characters
Abstract:
Pairs of binary sequences formed using linear combinations of multiplicative characters of finite fields are exhibited that, when compared with a random sequence pairs, simultaneously achieve significantly lower mean square autocorrelation values (for each sequence in the pair) and significantly lower mean square crosscorrelation values. If we define crosscorrelation merit factor analogously to the usual merit factor for autocorrelation, and if we define demerit factor as the reciprocal of merit factor, then randomly selected binary sequence pairs are known to have an average crosscorrelation demerit factor of 1. Our constructions provide sequence pairs with a crosscorrelation demerit factor significantly less than 1, and at the same time, the autocorrelation demerit factors of the individual sequences can also be made significantly less than 1 (which also indicates better than average performance). The sequence pairs studied here provide combinations of autocorrelation and crosscorrelation performance that are not achievable using sequences formed from single characters, such as maximal linear recursive sequences (m-sequences) and Legendre sequences. In this paper, exact asymptotic formulae are proved for the autocorrelation and crosscorrelation merit factors of sequence pairs formed using linear combinations of multiplicative characters. Data is presented that shows that the asymptotic behavior is closely approximated by sequences of modest length.
Autors: Kelly T. R. Boothby;Daniel J. Katz;
Appeared in: IEEE Transactions on Information Theory
Publication date: Oct 2017, volume: 63, issue:10, pages: 6158 - 6178
Publisher: IEEE
 
» Low RF-Complexity Massive MIMO Systems Based on Vertical Spatial Filtering for Urban Macro Cellular Networks
Abstract:
In this paper, we consider a massive multiple-input multiple-output (MIMO) system for urban macro cellular networks. A new technique named vertical spatial filtering (VSF) is proposed to achieve low radio frequency (RF) complexity by exploiting the spatial beam redundancy in elevation domain. Specifically, VSF consists of two parts: beam mapping and beam selection. We first adopt beam mapping to transform the received signals from antenna space into beam space. Then, we use beam selection to pick out part of the RF chains so as to realize the reduction of RF complexity. A three-dimensional channel model is adopted to evaluate the system performance. Two strategies for beam selection are proposed and numerical results are presented. The results show that the reduced system with VSF has the performance comparable to the complete system, while only a small amount of RF chains is required in vertical dimension of the two-dimensional base station array.
Autors: Xiaolei Jiang;Han Wang;Zhijun Zhang;Xinyu Gao;Linglong Dai;Magdy F. Iskander;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Oct 2017, volume: 66, issue:10, pages: 9214 - 9225
Publisher: IEEE
 
» Low-Complexity Digit-Level Systolic Gaussian Normal Basis Multiplier
Abstract:
Normal basis multiplication over is widely used in various applications such as elliptic curve cryptography. As a special class of normal basis with low complexity, Gaussian normal basis (GNB) has received considerable attention recently. In this paper, we propose a novel decomposition algorithm to develop a digit-level (DL) low-complexity systolic structure for GNB multiplication over . First, we propose two algorithms separately to achieve a systolic GNB multiplier with low critical path delay and low register complexity. Next, we present the corresponding structure according to the proposed algorithm (combination of previous two proposed algorithms). Compared with the existing systolic DL GNB multipliers (through both the theoretical and application-specific integrated circuit comparison), the proposed multiplier achieves significantly less area-delay product (ADP), e.g., for a systolic structure of digit size of 8 for , the proposed structure has 12.3% less ADP compared to the best of the existing designs, for the same digit size.
Autors: Qiliang Shao;Zhenji Hu;Shaobo Chen;Pingxiuqi Chen;Jiafeng Xie;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Oct 2017, volume: 25, issue:10, pages: 2817 - 2827
Publisher: IEEE
 
» Low-Complexity Scheduling and Power Adaptation for Coordinated Cloud-Radio Access Networks
Abstract:
In practical wireless systems, the successful implementation of resource allocation techniques strongly depends on the algorithmic complexity. Consider a cloud-radio access network (CRAN), where the central cloud is responsible for scheduling devices to the frames’ radio resources blocks (RRBs) of the single-antenna base-stations (BSs), adjusting the transmit power levels, and for synchronizing the transmit frames across the connected BSs. Previous studies show that the jointly coordinated scheduling and power control problem in the considered CRAN can be solved using an approach that scales exponentially with the number of BSs, devices, and RRBs, which makes the practical implementation infeasible for reasonably sized networks. This letter instead proposes a low-complexity solution to the problem, under the constraints that each device cannot be served by more than one BS but can be served by multiple RRBs within each BS frame, and under the practical assumption that the channel is constant during the duration of each frame. The paper utilizes graph-theoretical based techniques and shows that constructing a single power control graph is sufficient to obtain the optimal solution with a complexity that is independent of the number of RRBs. Simulation results reveal the optimality of the proposed solution for slow-varying channels, and show that the solution performs near-optimal for highly correlated channels.
Autors: Ahmed Douik;Hayssam Dahrouj;Tareq Y. Al-Naffouri;Mohamed-Slim Alouini;
Appeared in: IEEE Communications Letters
Publication date: Oct 2017, volume: 21, issue:10, pages: 2298 - 2301
Publisher: IEEE
 
» Low-Cost Adaptive Lebesgue Sampling Particle Filtering Approach for Real-Time Li-Ion Battery Diagnosis and Prognosis
Abstract:
In the past decades, fault diagnosis and prognosis (FDP) approaches were developed in the Riemann sampling (RS) framework, in which samples are taken and algorithms are executed in periodic time intervals. With the increase of system complexity, a bottleneck of real-time implementation of RS-based FDP is limited calculation resources, especially for distributed applications. To overcome this problem, a Lebesgue sampling-based FDP (LS-FDP) is proposed. LS-FDP takes samples on the fault dimension axis and provides a need-based FDP philosophy in which the algorithm is executed only when necessary. In previous LS-FDP, the Lebesgue length is a constant. To accommodate the nonlinear fault dynamics, it is desirable to execute FDP algorithm more frequently when the fault growth is fast while less frequently when fault growth is slow. This requires to change the Lebesgue length adaptively and optimize the selection of Lebesgue length based on fault state and fault growth speed. The goal of this paper is to develop an improved LS-FDP method with adaptive Lebesgue length, which enables the FDP to be executed according to fault dynamics and has low cost in terms of computation and hardware resource needed. The design and implementation of adaptive LS-FDP (ALS-FDP) based on a particle filtering algorithm are illustrated with a case study of Li-ion batteries to verify the performances of the proposed approach. The experimental results show that ALS-FDP keeps close monitoring of fault growth and is accurate and time-efficient on long-term prognosis.

Note to Practitioners—Traditional fault diagnosis and prognosis (FDP) approaches are based on the Riemann sampling (RS) method, in which samples are taken and algorithms are executed in periodic time intervals no matter if it is necessary. To reduce computation and make optimal use of computational resources, Lebesgue sampling method is introduced into FDP. In this Lebesgue sampling-based appr- ach, Lebesgue states are defined on the fault dimension axis and algorithm is executed only when the measurement causes a transition from one Lebesgue state to another, or an event happens. Different from RS-based approach, this is a need-based FDP philosophy in which the algorithm is executed only when necessary. This paper studies a parameter adaption method to optimally adjust the Lebesgue state length, which results in the changes of number and location of Lebesgue states, according to fault state and fault growth speed to accommodate the nonlinearity of fault dynamics and achieve a balance between computation and performance. The application to the capacity degradation of a set of Li-ion batteries is presented to demonstrate the effectiveness of the proposed adaptive Lebesgue state length FDP method.

Autors: Wuzhao Yan;Bin Zhang;Wanchun Dou;Datong Liu;Yu Peng;
Appeared in: IEEE Transactions on Automation Science and Engineering
Publication date: Oct 2017, volume: 14, issue:4, pages: 1601 - 1611
Publisher: IEEE
 
» Low-cost WDM fronthaul enabled by partitioned asymmetric AWGR with simultaneous flexible transceiver assignment and chirp management
Abstract:
The explosion of mobile traffic requires fronthaul networks to provide huge data capacity. One straightforward solution is to use wavelength division multiplexing (WDM) technologies with a sufficient number of transceivers, but the massive deployment of fronthaul networks inevitably adds transceiver cost. In this paper, we propose and demonstrate a low-cost scheme using a partitioned asymmetric arrayed waveguide grating router (AWGR) and distributed feedback Bragg (DFB) directly modulated lasers (DMLs) for WDM fronthaul. First, the centralization feature of a cloud radio access network (C-RAN) puts the transceivers together by nature, offering the potential to reduce the number of deployed transceivers based on optical switching fabric. We design what we believe is a novel asymmetric N × M AWGR-based switching fabric featuring a "partitioned cyclic routing" property that (i) enables flexible contention-free transceiver assignment; (ii) relaxes the requirement of tuning range, which allows the use of DFB lasers with moderate tuning range; and (iii) changes the diversity of the tuning range from N types to N∕M types. We also investigate the scalability of the scheme and show its rearrangeable contention-free assignment feature. Second, to adopt cost-effective DMLs, the intrinsic Gaussian-shape AWGR's edge filtering is employed to manage the frequency chirp of DFB DMLs, avoiding additional optical or electrical processing modules. Experiments are conducted to demonstrate the robustness of this scheme. In particular, we report that the allowable optical signal's frequency deviation ranges from −7.5 GHz to 7 GHz, and the induced additional crosstalk to AWGR’s adjacent port due to a deliberate frequency offset is far below the system design limit. In addition, the scheme is compatible with common 50 GHz, 100 GHz, and 200 GHz channel spacing AWGRs
Autors: Kuo Zhang;Qunbi Zhuge;Haiyun Xin;Hao He;Weisheng Hu;David V. Plant;
Appeared in: IEEE/OSA Journal of Optical Communications and Networking
Publication date: Oct 2017, volume: 9, issue:10, pages: 876 - 888
Publisher: IEEE
 
» Low-Loss Compact Silicon Nitride Arrayed Waveguide Gratings for Photonic Integrated Circuits
Abstract:
We report on low-loss, low-crosstalk, and compact arrayed waveguide gratings (AWGs) based on a 200-nm-thick-Si3 N4-core platform. High-resolution fabrication processes realized four types of Si3N4 AWG devices: 8 channel × 200 GHz, 16 channel × 100 GHz, 16 channel × 50 GHz, and 16 channel × 25 GHz AWGs. The insertion loss values of the four devices were 1.5 dB, 1.7 dB, 1.8 dB, and 2.7 dB; the corresponding crosstalk values were –24 dB, –21 dB, –20 dB, and –13 dB; footprints were 1.8 × 0.6 mm2, 2.2 × 0.7 mm2, 3.7 × 0.7 mm2, and 6.8 × 0.7 mm2, respectively.
Autors: Kuanping Shang;Shibnath Pathak;Chuan Qin;S. J. Ben Yoo;
Appeared in: IEEE Photonics Journal
Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 5
Publisher: IEEE
 
» Low-Loss Connection of Embedded Optical Fiber Sensors Using a Self-Written Waveguide
Abstract:
This letter reports on a new concept for making a low-loss connection to an optical fiber sensor, which is embedded in a fiber reinforced composite material for structural health monitoring. First, a cross section of the composite is made to reveal the end-face of the embedded optical fiber. Then, an external fiber is aligned and an intermediate polymer-based self-written waveguide (SWW) is fabricated between both fibers. This SWW bridges the gap and serves as mode size converter ensuring a low-loss optical connection even if both fibers have dissimilar mode field diameters. The advantage of this approach is that no special care needs to be taken during the composite production cycle not to damage the sensor fiber in- or egress points, since it will be reconnected afterward.
Autors: Jeroen Missinne;Geert Luyckx;Eli Voet;Geert Van Steenberge;
Appeared in: IEEE Photonics Technology Letters
Publication date: Oct 2017, volume: 29, issue:20, pages: 1731 - 1734
Publisher: IEEE
 
» Low-Pass FSS for 50–230 GHz Quasi-Optical Demultiplexing for the MetOp Second-Generation Microwave Sounder Instrument
Abstract:
This paper reports the design, manufacture, and characterization of a new frequency selective surface (FSS) structure which meets the demanding requirements for transmission of 50.2–57.7 GHz radiation simultaneously for TE and TM polarizations at 45° incidence, and reflection of signals in four discrete higher frequency bands centered at 89, 165.5, 183.3, and 229 GHz. The FSS is required for a quasi-optical network, which was developed during the preparatory breadboarding of the microwave sounder instrument. The 100 mm diameter ultrawideband FSS must exhibit ≤0.25 dB loss for all signals in the above bands, and has to satisfy the requirements of the space environment. The FSS is formed by a periodic metal film array sandwiched between two 0.83 mm thick, optically flat, fused quartz substrates. It has 19 000 unit cells composed of two compact resonant slot elements, a meandering elliptical annulus and a folded dipole. Spectral transmission and reflection measurements in the 50–230 GHz frequency range yielded results that are in excellent agreement with numerical predictions.
Autors: Raymond Dickie;Steven Christie;Robert Cahill;Paul Baine;Vincent Fusco;Kai Parow-Souchon;Manju Henry;Peter G. Huggard;Robert S. Donnan;Oleksandr Sushko;Massimo Candotti;Rostyslav Dubrovka;Clive G. Parini;Ville Kangas;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Oct 2017, volume: 65, issue:10, pages: 5312 - 5321
Publisher: IEEE
 
» Low-Power Digital Baseband Transceiver Design for UWB Physical Layer of IEEE 802.15.6 Standard
Abstract:
This paper presents the design and implementation of ultrawideband digital baseband transceiver for wireless body area networks (WBAN) applications. The power dissipation and area of the proposed architecture are minimized by combining algorithmic and architectural level modifications. A new algorithm for Bose–Chaudhuri–Hocquenghem (BCH) encoding is implemented and the coding gain of the BCH decoder is improved by 0.5 dB, with a cost of only one percent area overhead. An area efficient, low-complexity, and low-power BCH decoder is implemented and it has 42 lower area and 38 lower power dissipation compared to a conventional hard-decision decoder. Other salient features of this paper include a low-complexity, low-power packet detection unit, and a low-power module for removing the shortening bits. The baseband transceiver has been designed in 90 nm CMOS technology and it has an energy efficiency of 73 pJ/bit in transmitter mode and 225 pJ/bit in receiver mode.
Autors: Pavan Kumar Manchi;Roy Paily;Anup Kumar Gogoi;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Oct 2017, volume: 13, issue:5, pages: 2474 - 2483
Publisher: IEEE
 
» Low-Power Transparent RFID Circuits Using Enhancement/Depletion Logic Gates Based on Deuterium-Treated ZnO TFTs
Abstract:
Transparent radio frequency identification (RFID) integrated circuits based on ZnO thin film transistors were developed by using ratioed logic gates with depletion loads. The fabrication of these logic gates employed a simple deuterium plasma treatment to adjust the threshold voltages of the load transistors. Inverters were realized with full swing (0.02 ~4.99V), high gain of −48V/V, large noise margin, and small area. RFID circuits based on such logic gates exhibited ultra-low power dissipation of at a supply voltage of 2.4 V and a considerably high data rate of 1.6 kb/s, which may open up possibilities for applications including transparent, low-cost RFID tags.
Autors: Hua Xu;Zhi Ye;Ni Liu;Ying Wang;Ning Zhang;Yang Liu;
Appeared in: IEEE Electron Device Letters
Publication date: Oct 2017, volume: 38, issue:10, pages: 1383 - 1386
Publisher: IEEE
 
» Low-Profile Distributed Cavity Resonators and Filters
Abstract:
In this paper, a new family of low-profile high quality factor cavity resonators, termed distributed resonators, is introduced. Initially, the theory of operation of the proposed distributed resonator is presented regarding two, three, and four coupled resonator elements. Based on this, a further-improved arrangement of resonator elements is proposed. It is shown that the height of the individual resonator can be controlled by the number of resonant elements and can be almost arbitrarily low. As an experimental verification, a three-pole filter operating at 1800 MHz with a bandwidth of 40 MHz is designed and fabricated. The individual resonator of this filter comprises 25 individual resonant elements, with an overall cavity height of 7 mm, or 15°, and an unloaded quality factor of 1900. The height of the presented filter is significantly lower than any other air-filled filter cavity solution available in the literature. The measured insertion loss of the filter is 0.5 dB, which is in excellent agreement with the theoretically predicted value of 0.4 dB.
Autors: Senad Bulja;Martin Gimersky;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Oct 2017, volume: 65, issue:10, pages: 3769 - 3779
Publisher: IEEE
 
» Low-Rank-Based Nonlocal Adaptive Loop Filter for High-Efficiency Video Compression
Abstract:
In video coding, the in-loop filtering has emerged as a key module due to its significant improvement on compression performance since H.264/Advanced Video Coding. Existing incorporated in-loop filters in video coding standards mainly take advantage of the local smoothness prior model used for images. In this paper, we propose a novel adaptive loop filter utilizing image nonlocal prior knowledge by imposing the low-rank constraint on similar image patches for compression noise reduction. In the filtering process, the reconstructed frame is first divided into image patch groups according to image patch similarity. The proposed in-loop filtering is formulated as an optimization problem with low-rank constraint for every group of image patches independently. It can be efficiently solved by soft-thresholding singular values of the matrix composed of image patches in the same group. To adapt the properties of the input sequences and bit budget, an adaptive threshold derivation model is established for every group of image patches according to the characteristics of compressed image patches, quantization parameters, and coding modes. Moreover, frame-level and largest coding unit-level control flags are signaled to further improve the adaptability from the sense of rate-distortion optimization. The performance of the proposed in-loop filter is analyzed when it collaborates with the existing in-loop filters in High Efficiency Video Coding. Extensive experimental results show that our proposed in-loop filter can further improve the performance of state-of-the-art video coding standard significantly, with up to 16% bit-rate savings.
Autors: Xinfeng Zhang;Ruiqin Xiong;Weisi Lin;Jian Zhang;Shiqi Wang;Siwei Ma;Wen Gao;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Oct 2017, volume: 27, issue:10, pages: 2177 - 2188
Publisher: IEEE
 
» Low-VDD Operation of SRAM Synaptic Array for Implementing Ternary Neural Network
Abstract:
For Internet of Things (IoT) edge devices, it is very attractive to have the local sensemaking capability instead of sending all the data back to the cloud for information processing. For image pattern recognition, neuro-inspired machine learning algorithms have demonstrated enormous powerfulness. To effectively implement learning algorithms on-chip for IoT edge devices, on-chip synaptic memory architectures have been proposed to implement the key operations such as weighted-sum or matrix-vector multiplication. In this paper, we proposed a low-power design of static random access memory (SRAM) synaptic array for implementing a low-precision ternary neural network. We experimentally demonstrated that the supply voltage (VDD) of the SRAM array could be aggressively reduced to a level, where the SRAM cell is susceptible to bit failures. The testing results from 65-nm SRAM chips indicate that VDD could be reduced from the nominal 1–0.55 V (or 0.5 V) with a bit error rate ~0.23% (or ~1.56%), which only introduced ~0.08% (or ~1.68%) degradation in the classification accuracy. As a result, the power consumption could be reduced by more than (or ).
Autors: Xiaoyu Sun;Rui Liu;Yi-Ju Chen;Hsiao-Yun Chiu;Wei-Hao Chen;Meng-Fan Chang;Shimeng Yu;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Oct 2017, volume: 25, issue:10, pages: 2962 - 2965
Publisher: IEEE
 
» LPM-Based Shielding Performance Analysis of High-Voltage Substations Against Direct Lightning Strokes
Abstract:
The leader progression model (LPM) is employed to investigate the shielding system performance of high-voltage substations against direct lightning strokes in the presence of substation instruments. The substation is simulated in detail for high accurate calculation of the shielding failure rate. Almost all of the apparatuses are modeled as fictitious charges in the stepwise simulations of LPM. The charge simulation method is used for finding the electrical field during the lightning movement. The probability of upward leader propagation is considered from all apparatuses. For more practical simulation, the environmental conditions are also included in simulations. The investigations are implemented on a test case and a practical high-voltage substation. The results are compared to those of the electrogeometric model. It is very likely that the results of this paper better simulate reality because lots of parameters have been taken into account. The results reveal that the presence of substation instruments increases the striking distance and the SF since they attract the lightning moving down near the substation.
Autors: Abolfazl Rahiminejad;Behrooz Vahidi;
Appeared in: IEEE Transactions on Power Delivery
Publication date: Oct 2017, volume: 32, issue:5, pages: 2218 - 2227
Publisher: IEEE
 
» LPPFusion to initiate fusion, the company's desktop device exploits instability [Resources_Startups]
Abstract:
Since nuclear fusion's earliest days, the sun has served as the ultimate prototype. It's the closest continuously functioning large-scale fusion reactor, after all. Why not copy from the best? So tokamaks, stellarators, and laser ignition facilities all strive to create high-pressure and high-temperature plasmas that behave like microcosms of the sun's core. One of the biggest challenges these systems face is achieving the tight control they require over the plasma fuel they seek to fuse. But one New Jersey fusion startup company is taking a very different tack: "Guide the plasma's instability; don't fight it," says Eric Lerner, president and chief scientist at LPPFusion, based in Middlesex, N.J.
Autors: Mark Anderson;
Appeared in: IEEE Spectrum
Publication date: Oct 2017, volume: 54, issue:10, pages: 17 - 18
Publisher: IEEE
 
» Lunar Brightness Temperature Model Based on the Microwave Radiometer Data of Chang’e-2
Abstract:
The brightness temperature (TB) data of the Moon acquired by the microwave radiometer (MRM) on-board the Chinese Chang’e-2 (CE-2) lunar probe are valuable and comprehensive data, which can be helpful in studying the physical properties of the lunar regolith, such as thickness, physical temperature, and dielectric constant. To construct the accurate and high-resolution lunar TB model with the TB data obtained by the MRM on-board CE-2, 2401 tracks of the original TB data are quantized by using the hour angle processing, and the hierarchical MK splines function (HMKSF) method is presented, which uses a hierarchy of coarse-to-fine control lattices to generate a sequence of TB model functions. The TB model constructor is the sum of the TB model functions derived at each level of the hierarchy. In addition, the lunar TB models with a resolution of in all four frequency channels are constructed for both the daytime and the nighttime. The obtained models show rich information, e.g., the global distribution of TB over the lunar surface, the effect of frequency on the TB model.
Autors: Zhanchuan Cai;Ting Lan;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Oct 2017, volume: 55, issue:10, pages: 5944 - 5955
Publisher: IEEE
 
» Machine Intelligence Based Data Handling Framework for Ship Energy Efficiency
Abstract:
Appropriate navigation strategies should be developed to overcome the current shipping industrial challenges under emission-control-based energy efficiency measures. Effective navigation strategies should be based on accurate ship performance and navigation information; therefore, various onboard data handling systems are installed on ships to collect large-scale datasets. Ship performance and navigation data that are collected to develop such navigation strategies can be an integrated part of the ship energy efficiency management plan (SEEMP). Hence, the SEEMP with various navigation strategies can play an important part of e-navigation under modern integrated bridge systems. This study proposes a machine-intelligence-based data handling framework for ship performance and navigation data to improve the quality of the respective navigation strategies. The prosed framework is divided into two main sections of pre and post processing. The data pre-processing is an onboard application that consists of sensor faults detection, data classification, and data compression steps. The data post processing is a shore-based application (i.e., in data centers) and that consists of data expansion, integrity verification, and data regression steps. Finally, a ship performance and navigation dataset of a selected vessel is analyzed through the proposed framework and successful results are presented in this study.
Autors: Lokukaluge Prasad Perera;Brage Mo;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Oct 2017, volume: 66, issue:10, pages: 8659 - 8666
Publisher: IEEE
 
» Magnetic and Microwave Absorption Properties of Magnetite (Fe3O4)@Conducting Polymer (PANI, PPY, PT) Composites
Abstract:
Magnetite nanoparticles (Fe3O4 NPs) were synthesized via reflux co-precipitation method and coated with various polymeric media of polypyrrole (PPY), polyaniline (PANI), and polythiophene (PT) in the same experiment conditions. The increasing crystallinity and the absence of another phase were investigated from X-ray diffraction experiments. Fe3O4 NPs have spherical shapes and after polymer coating their mean size were found as 11.76, 11.51, and 9.98 nm for Fe3O4@PPY, Fe3O4@PANI, and Fe3O4@PT, respectively. The superparamagnetic nature of composites was observed at room temperature. The electromagnetic (EM) wave reflection loss of samples was analyzed comparatively. It was found that the type of the polymers coated on the magnetite nanoparticles in the same procedure gives slight change in reflection loss of EM waves.
Autors: Ibrahim Saim Unver;Zehra Durmus;
Appeared in: IEEE Transactions on Magnetics
Publication date: Oct 2017, volume: 53, issue:10, pages: 1 - 8
Publisher: IEEE
 
» Magnetic Guidance [Turnstile]
Abstract:
Discusses the role that magnetic-aerotactic bacteria will play in the field of medicine.
Autors: Rajeev Bansal;
Appeared in: IEEE Antennas and Propagation Magazine
Publication date: Oct 2017, volume: 59, issue:5, pages: 138 - 138
Publisher: IEEE
 
» Magnetoresistance Relaxation Anisotropy of Nanostructured La-Sr(Ca)-Mn-O Films Induced by High-Pulsed Magnetic Fields
Abstract:
The results of investigation of colossal magnetoresistance relaxation in nanostructured La-Sr(Ca)-Mn-O films upon removal of magnetic field pulse are presented. Thin films having thicknesses of 75–350 nm grown by pulsed injection metal–organic chemical vapor deposition technique were studied in pulsed magnetic fields having duration of 0.9 ms and amplitudes of 2–12 T. It was obtained that “fast” relaxation process occurring in hundred microseconds time scale exhibits anisotropy: the magnitude of remnant resistivity is approximately three times smaller and the process is faster when magnetic field is applied perpendicular to the film plane in comparison with in-plane direction. The dynamics of this relaxation process was analyzed using Kolmogorov–Avrami–Fatuzzo model, taking into account nucleation and reorientation of magnetic domains into equilibrium state. The “fast” remnant relaxation was not observed after the application of longer pulses (20 ms) having amplitude of 60 T. Influence of remnant relaxation on operation of B-scalar magnetic field sensors based on nanostructured manganite films is discussed.
Autors: Nerija Žurauskienė;Dainius Pavilonis;Jonas Klimantavičius;Saulius Balevičius;Voitech Stankevič;Remigijus Vasiliauskas;Valentina Plaušinaitienė;Adulfas Abrutis;Martynas Skapas;Remigijus Jušk
Appeared in: IEEE Transactions on Plasma Science
Publication date: Oct 2017, volume: 45, issue:10, pages: 2773 - 2779
Publisher: IEEE
 
» Major Trends Impacting Power Systems [From the Editor's Desk]
Abstract:
Presents the introductory editorial for this issue of the publication.
Autors: Lanny Floyd;
Appeared in: IEEE Industry Applications Magazine
Publication date: Oct 2017, volume: 23, issue:5, pages: 3 - 3
Publisher: IEEE
 
» Majority Logic Decoding Under Data-Dependent Logic Gate Failures
Abstract:
A majority logic decoder made of unreliable logic gates, whose failures are transient and data-dependent, is analyzed. Based on a combinatorial representation of fault configurations a closed-form expression for the average bit error rate for a one-step majority logic decoder is derived, for a regular low-density parity-check (LDPC) code ensemble and the proposed failure model. The presented analysis framework is then used to establish bounds on the one-step majority logic decoder performance under the simplified probabilistic gate-output switching model. Based on the expander property of Tanner graphs of LDPC codes, it is proven that a version of the faulty parallel bit-flipping decoder can correct a fixed fraction of channel errors in the presence of data-dependent gate failures. The results are illustrated with numerical examples of finite geometry codes.
Autors: Srdan Brkic;Predrag Ivaniš;Bane Vasić;
Appeared in: IEEE Transactions on Information Theory
Publication date: Oct 2017, volume: 63, issue:10, pages: 6295 - 6306
Publisher: IEEE
 
» Make the web better for everyone [Spectral Lines]
Abstract:
The Web has serious problems: peddler of unreliable information, haven for criminals, spawning ground for irrational conspiracy fears, and tool for destructive people to broadcast their violence in real time and with posted recordings. No doubt your list of Web pathologies is different from mine. But surely you agree that the Web disappoints as much as it delights. Now the hard part-what to do about it? Starting over is impossible. The Web is the ground of our global civilization, a pillar of contemporary existence. Even as we complain about the excesses and shortcomings of the Web, we can't survive without it. For engineers and technovisionaries, the solution flows from an admirable U.S. tradition: building a better mousetrap. For redesigners of the broken Web, the popular impulse is to expand digital freedom by creating a Web so decentralized that governments can't censor it and big corporations can't dominate. However noble, the freedom advocates fail to account for a major class of vexations arising from anonymity, which allows, say, Russian hackers to pose as legitimate tweeters and terrorist groups to recruit through Facebook pages. To be sure, escape from government surveillance through digital masks has benefits, yet the path to improved governance across the world doesn't chiefly lie with finding more clever ways to hide from official oppression. More freedom, ultimately, will only spawn more irresponsible, harmful behavior. If more freedom and greater privacy won't cure what ails the Web, might we consider older forms of control and the cooperation of essential public services?
Autors: G. Pascal Zachary;
Appeared in: IEEE Spectrum
Publication date: Oct 2017, volume: 54, issue:10, pages: 8 - 8
Publisher: IEEE
 
» Mandatory Content Access Control for Privacy Protection in Information Centric Networks
Abstract:
Several Information Centric Network (ICN) architectures have been proposed as candidates for the future Internet, aiming to solve several salient problems in the current IP-based Internet architecture such as mobility, content dissemination and multi-path forwarding. In general, security and privacy are considered as essential requirements in ICN. However, existing ICN designs lack built-in privacy protection for content providers (CPs), e.g., any router in an Internet Service Provider in ICN can cache any content, which may result in information leakage. In this paper, we propose Mandatory Content Access Control (MCAC), a distributed information flow control mechanism to enable a content provider to control which network nodes can cache its contents. In MCAC, a CP defines different security labels for different contents, and content routers check these labels to decide if a content object should be cached. To ensure correct enforcement of MCAC, we also propose a design of a trusted architecture by extending existing mainstream router architectures. We evaluate the performance of MCAC in the NS-3 simulator. The simulation results show that enforcing MCAC in routers does not introduce significant overhead in content forwarding.
Autors: Qi Li;Ravi Sandhu;Xinwen Zhang;Mingwei Xu;
Appeared in: IEEE Transactions on Dependable and Secure Computing
Publication date: Oct 2017, volume: 14, issue:5, pages: 494 - 506
Publisher: IEEE
 
» Manifold Learning by Curved Cosine Mapping
Abstract:
In the field of pattern recognition, data analysis, and machine learning, data points are usually modeled as high-dimensional vectors. Due to the curse-of-dimensionality, it is non-trivial to efficiently process the orginal data directly. Given the unique properties of nonlinear dimensionality reduction techniques, nonlinear learning methods are widely adopted to reduce the dimension of data. However, existing nonlinear learning methods fail in many real applications because of the too-strict requirements (for real data) or the difficulty in parameters tuning. Therefore, in this paper, we investigate the manifold learning methods which belong to the family of nonlinear dimensionality reduction methods. Specifically, we proposed a new manifold learning principle for dimensionality reduction named Curved Cosine Mapping (CCM). Based on the law of cosines in Euclidean space, CCM applies a brand new mapping pattern to manifold learning. In CCM, the nonlinear geometric relationships are obtained by utlizing the law of cosines, and then quantified as the dimensionality-reduced features. Compared with the existing approaches, the model has weaker theoretical assumptions over the input data. Moreover, to further reduce the computation cost, an optimized version of CCM is developed. Finally, we conduct extensive experiments over both artificial and real-world datasets to demonstrate the performance of proposed techniques.
Autors: Huamao Gu;Xun Wang;Xuewen Chen;Shaoping Deng;Jinqin Shi;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Oct 2017, volume: 29, issue:10, pages: 2236 - 2248
Publisher: IEEE
 
» Manipulation and Transportation With Cooperative Underwater Vehicle Manipulator Systems
Abstract:
Autonomous underwater manipulation has been a topic of interest since the early 1990s. In the past few years, several milestone projects such as SAUVIM and TRIDENT have demonstrated autonomy capabilities for a single underwater vehicle manipulator system (UVMS) in performing simple manipulation tasks, e.g., the recovery of an object from the seafloor. The Italian funded MARIS project aims to extend some of these results to multiple UVMSs performing a cooperative transportation task of a long object such as a pipe. This paper presents the results achieved in developing a unifying architecture for the control of both individually and cooperatively operating UVMSs which explicitly makes use of a limited amount of information exchange between the agents, which is needed due to the severe bandwidth limitations of the underwater acoustic communications. A complete execution of the reference transportation mission is presented to support the proposed distributed algorithm. Furthermore, hydrodynamic simulations of the cooperative transportation phase are presented and an analysis of the achievable performances as different communication schemes are employed is given.
Autors: Enrico Simetti;Giuseppe Casalino;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Oct 2017, volume: 42, issue:4, pages: 782 - 799
Publisher: IEEE
 
» Marx Multilevel Bipolar Modulator Dynamic Models for Load Transient Analysis
Abstract:
This paper presents generalized dynamic models for Marx derived multilevel half-bridge bipolar modulators. This high-voltage topology uses modular Marx multilevel converter diode (CD) cells to generate positive and negative (bipolar) pulses or unipolar (positive or negative voltage pulses). The developed models are tested in transient studies of pulse voltages and currents in the load. Simulation and experimental results are presented and compared.
Autors: L. Lamy Rocha;J. Fernando Silva;L. M. Redondo;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Oct 2017, volume: 45, issue:10, pages: 2611 - 2617
Publisher: IEEE
 
» Mathematical Modeling and Parameter Optimization of Fine Particle Sensors Based on Laser Light Scattering
Abstract:
Fine particles have promoted air quality monitoring need of humankind after their harmful effects on human health are pathologically verified. To monitor fine particle concentrations at a low cost, laser light scattering technique is favored by many researchers. While several cheap and interesting sensors are developed, little attention is paid to the measurement model, which in turn bound the sensor precision. In order to alleviate this situation, a simplified model is proposed, which can describe the nonlinear relationship between particle volume and single particle angular light flux by considering the effect of Rayleigh scattering and Fraunhofer diffraction simultaneously. The model can be employed in the signal processing of commercial low-cost particle sensors based on laser light scattering. A data-driven approach is adopted to find the optimum parameters of this model by considering different kinds of fine particles. Based on Trust-Region and Levenberg-Marquardt methods combining with robust methods, the optimum parameters of this model are obtained. To verify the effectiveness of the proposed model, comparative experiments are conducted on: a particle sensor with and without parameter optimization, a DustTrak II 8530 monitor and a reference TEOM PM2.5 monitor. The results indicated that the optimal model improves the measurement accuracy of the fine particle mass concentration by 10%.
Autors: Wenjia Shao;Hongjian Zhang;Hongliang Zhou;
Appeared in: IEEE Sensors Journal
Publication date: Oct 2017, volume: 17, issue:20, pages: 6672 - 6681
Publisher: IEEE
 
» MATLAB-Based Interactive Tool for Teaching Electromagnetics [Education Corner]
Abstract:
Presents information on the MATLAB-Based Interactive tool for teaching electromagnetics. This was created for a second-year university-level electromagnetics course using a MATLAB-based graphical user interface (GUI). It aims to improve learning outcomes, reduce staff workload, and engage online students through blended learning. The tool allows for the random generation of inputs for a large number of problems, provides automatic feedback when the answers are incorrect, and generates a report when the answers are correct. Examples of electrostatics, magnetostatics, dynamic fields, and transmission lines problem sets are presented.
Autors: Hugo G. Espinosa;David V. Thiel;
Appeared in: IEEE Antennas and Propagation Magazine
Publication date: Oct 2017, volume: 59, issue:5, pages: 140 - 146
Publisher: IEEE
 
» Maturity Model of Information Security for Software Developers
Abstract:
Currently the software developers have to worry about protecting your information and customer information which it has access. ISO 27001 is currently the largest reference in security procedures Information (SI). This paper presents an information security maturity model based on ISO 27001 for software developers. The model was evaluated by experts in the subject and used to assess the level of maturity of some Brazilian companies. The results of the evaluations showed that the model is a tool that can be used for companies to deploy SI processes.
Autors: Marcelo Pereira da Silva;Rodolfo Miranda de Barros;
Appeared in: IEEE Latin America Transactions
Publication date: Oct 2017, volume: 15, issue:10, pages: 1994 - 1999
Publisher: IEEE
 
» Maximizing Capacity in Cognitive Radio Networks Under Physical Interference Model
Abstract:
A fundamental problem in cognitive radio networks (CRN) is the following capacity maximization in CRN (CM-CRN) problem: given a set of primary links with a common transmitter, together with a set of secondary links, select a maximum cardinality subset of the links that can concurrently transmit successfully under the constraint that all primary links are selected. This problem is intrinsically different from the well-known link scheduling (LS) problem in wireless mesh networks, which does not have the constraint to select all primary links. In this paper, we make both theoretical and practical contributions to the CM-CRN problem. To achieve deep theoretical understanding of the problem, we show that CM-CRN is NP-hard and design a polynomial time approximation algorithm with a constant approximation ratio. In addition, we extend the designed algorithm to find approximate solutions to two variations of CM-CRN, one with the objective of maximizing the number of selected secondary links and the other with multiple primary users. To achieve good performance in practice, we design a simple but effective heuristic algorithm based on a greedy strategy. We also design an optimal algorithm based on integer linear programming, which serves as a benchmark for evaluating the performance of the approximation algorithm and heuristic algorithm, for problem instances of small sizes. Extensive evaluations show that our proved constant ratio of the approximation algorithm is considerably conservative and our heuristic algorithm produces results that are very close to the optimal solution. Our approximation algorithm for CM-CRN is motivated by and can be viewed as a non-trivial extension of the elegant approximation algorithm for the LS problem by Wan et al. to CRNs.
Autors: Michael Brown;Colin Marshall;Dejun Yang;Ming Li;Jian Lin;Guoliang Xue;
Appeared in: IEEE/ACM Transactions on Networking
Publication date: Oct 2017, volume: 25, issue:5, pages: 3003 - 3015
Publisher: IEEE
 
» Maximum Likelihood Estimation of Functionals of Discrete Distributions
Abstract:
We consider the problem of estimating functionals of discrete distributions, and focus on a tight (up to universal multiplicative constants for each specific functional) nonasymptotic analysis of the worst case squared error risk of widely used estimators. We apply concentration inequalities to analyze the random fluctuation of these estimators around their expectations and the theory of approximation using positive linear operators to analyze the deviation of their expectations from the true functional, namely their bias. We explicitly characterize the worst case squared error risk incurred by the maximum likelihood estimator (MLE) in estimating the Shannon entropy , and the power sum , up to universal multiplicative constants for each fixed functional, for any alphabet size and sample size for which the risk may vanish. As a corollary, for Shannon entropy estimation, we show that it is necessary and sufficient to have observations for the MLE to be consistent. In addition, we establish that it is necessary and sufficient to consider samples for the MLE to consistently estimate . The minimax rate-optimal estimators for both problems require samples, which implies that the MLE has a strictly sub-optimal sample complexity. When , we show that the worst case squared error rate of convergence for the MLE is for infinite alphabet size, while the minimax squared error rate is . When , the MLE achieves the minimax optimal rate regardless of the alphabet size. As an application of the general theory, we analyze the Dirichlet prior smoothing techniques for Shannon entropy estimation. In this context, one approach is to plug-in the Dirichlet prior smoothed distribution into the entropy functional, while the other one is to calculate the Bayes estimator for entropy under the Dirichlet prior for squared error, which is the conditional expectation. We show that in general such estimators do not improve over the maximum likelihood estimator. No matter how we tune the parameters in the Dirichlet prior, this approach cannot achieve the minimax rates in entropy estimation. The performance of the minimax rate-optimal estimator with samples is essentially at least as good as that of Dirichlet smoothed entropy estimators with samples.
Autors: Jiantao Jiao;Kartik Venkat;Yanjun Han;Tsachy Weissman;
Appeared in: IEEE Transactions on Information Theory
Publication date: Oct 2017, volume: 63, issue:10, pages: 6774 - 6798
Publisher: IEEE
 
» Maximum Versoria Criterion-Based Robust Adaptive Filtering Algorithm
Abstract:
Using the generalized Gaussian probability density function as the kernel, a generalized correntropy has been proposed. A generalized maximum correntropy criterion (GMCC) algorithm is then developed by maximizing the generalized correntropy. However, the GMCC algorithm has a high steady-state misalignment and involves a high calculation cost of the exponential term (generalized Gaussian kernel). In this brief, we propose a maximum Versoria criterion (MVC) algorithm, which is derived by maximizing the generalized Versoria function, to reduce steady-state misalignment and computational effort as compared to the GMCC algorithm. The MVC algorithm is then tested in system identification and acoustic echo cancellation scenarios, which have demonstrated that the proposed algorithm is robust against non-Gaussian impulsive noises and performs much better than the LMP and GMCC algorithms.
Autors: Fuyi Huang;Jiashu Zhang;Sheng Zhang;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Oct 2017, volume: 64, issue:10, pages: 1252 - 1256
Publisher: IEEE
 
» mCloud: A Context-Aware Offloading Framework for Heterogeneous Mobile Cloud
Abstract:
Mobile cloud computing (MCC) has become a significant paradigm for bringing the benefits of cloud computing to mobile devices’ proximity. Service availability along with performance enhancement and energy efficiency are primary targets in MCC. This paper proposes a code offloading framework, called mCloud, which consists of mobile devices, nearby cloudlets and public cloud services, to improve the performance and availability of the MCC services. The effect of the mobile device context (e.g., network conditions) on offloading decisions is studied by proposing a context-aware offloading decision algorithm aiming to provide code offloading decisions at runtime on selecting wireless medium and appropriate cloud resources for offloading. We also investigate failure detection and recovery policies for our mCloud system. We explain in details the design and implementation of the mCloud prototype framework. We conduct real experiments on the implemented system to evaluate the performance of the algorithm. Results indicate the system and embedded decision algorithm are able to provide decisions on selecting wireless medium and cloud resources based on different context of the mobile devices, and achieve significant reduction on makespan and energy, with the improved service availability when compared with existing offloading schemes.
Autors: Bowen Zhou;Amir Vahid Dastjerdi;Rodrigo N. Calheiros;Satish Narayana Srirama;Rajkumar Buyya;
Appeared in: IEEE Transactions on Services Computing
Publication date: Oct 2017, volume: 10, issue:5, pages: 797 - 810
Publisher: IEEE
 
» MCR: Structure-Aware Overlay-Based Latency-Optimal Greedy Relay Search
Abstract:
Geo-distributed network applications typically use relays to process and forward timely messages among clients. The state-of-the-art approaches greedily locate a relay that is closer to clients based on an overlay that favors neighbors in the immediate vicinity of the current node. Unfortunately, as clients are unknown a priori, the optimal relay is generally outside of the immediate vicinity of the current node. Consequently, the search process often terminates at a poor local minimum. In this paper, we address these challenges by designing and implementing a distributed relay-search system called MCR. In order to accurately locate a relay closer to clients, by observing that the latency space exhibits a proximity clustering phenomenon where nodes in the same cluster are typically within close proximity, we propose an overlay called MCRing that is aware of global proximity clusters. In order to scale well under dynamic relays, we maintain the proximity clusters via a gossiping-based clustering process. Furthermore, we propose a series of algorithms to accurately locate a relay that is closer to clients and satisfies the load constraints. We prove that the relay-search process achieves close to optimal results based on a doubling dimension-based analysis in an inframetric model. Finally, extensive evaluation via simulation and PlanetLab experiments shows that MCRing is able to locate near-optimal relays.
Autors: Yongquan Fu;Ernst Biersack;
Appeared in: IEEE/ACM Transactions on Networking
Publication date: Oct 2017, volume: 25, issue:5, pages: 3016 - 3029
Publisher: IEEE
 
» Measurement of the Ionospheric Scintillation Parameter $C_{k}L$ From SAR Images of Clutter
Abstract:
Space-based synthetic aperture radar (SAR) can be affected by the ionosphere, particularly at L-band and below. A technique is described that exploits the reduction in SAR image contrast to measure the strength of ionospheric turbulence parameter . The theory describing the effect of the ionosphere on the SAR point spread function (PSF) and the consequent effect on clutter is reviewed and extended. This theory can then be used to determine from both corner reflectors (CRs) and K-distributed SAR clutter. Measuring the K-distribution order parameter allows values much lower than those that defocus the image to be determined. The results of an experiment in which a CR on Ascension Island was repeatedly imaged by PALSAR-2 in the spotlight mode during the scintillation season are described. The value of obtained by measuring the clutter was compared with that obtained from a nearby CR. The correlation between the two was good using a median value of the spectral index . This correlation was improved by using the measured value of derived from the CR PSF. The technique works for any homogeneous K-distributed SAR clutter and is thus applicable to extra-terrestrial bodies as well as PALSAR-2 images of Ascension Island.
Autors: David P. Belcher;Christopher R. Mannix;Paul S. Cannon;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Oct 2017, volume: 55, issue:10, pages: 5937 - 5943
Publisher: IEEE
 
» Measurement-Based Evaluation on Detection Probability of Extended Squitter for Air-to-Ground Surveillance
Abstract:
Deployment of Automatic Dependent Surveillance—Broadcast (ADS-B) has commenced worldwide for aeronautical surveillance. In ADS-B, an aircraft broadcasts extended squitters, which include its position measured by the Global Navigation Satellite System. These squitters are received by ground stations. ADS-B has the potential to achieve higher accuracy and higher update rates than conventional radar, however, they are vulnerable to co-channel interference. Therefore, evaluating the performance of extended squitters in real interference environments is crucial for successful deployment of ADS-B, the goal of this work. Our approach is to gather and analyze measurement data from four experimental ground stations in the Kanto airspace, Japan. The measurement data are practical as the sites include two major airports and an antenna tower supporting air-ground communication. Analysis of the data yields a measurement-based model that can estimate the probability of detection of the extended squitter for given link-margin and interfering signal rate. To the best of the our knowledge, this is the first work to derive an expression for the probability of detection based on large-scale measurements. Two applications of the model are demonstrated. First, the improvement on performance made possible by using a sector antenna instead of an omni-directional antenna is predicted; the contributions of improved link-margin and reduced interference are given. Second, the ADS-B coverage is predicted along an experimental flight route.
Autors: Junichi Naganawa;Hiromi Miyazaki;Hirohisa Tajima;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Oct 2017, volume: 66, issue:10, pages: 8883 - 8894
Publisher: IEEE
 
» Measuring Heart and Breath Rates by Image Photoplethysmography using Wavelets Technique
Abstract:
This paper presents a method for contactless measuring of heart and respiratory rates by Photoplethysmography image technique through wavelets. This method is imperceptible to the humans, with the additional advantages of a low computational cost and high tolerance to artifacts. The approach uses the analysis of the plethysmographic signal collected by a standard color camera to estimate the heart and breathing rates. This system uses a pre-filter to reduce the offset of the averaged signal through numerical analysis techniques and the signal is processed by wavelets. Additionally, the measurement of respiration rate is decoupled from the sinus arrhythmia. A good estimate of the vital signs on ten individuals was obtained. The Bland-Altman analysis shows a strong correlation between measurements by standard systems and our approach.
Autors: Juan Carlos Cobos Torres;Mohamed Abderrahim;
Appeared in: IEEE Latin America Transactions
Publication date: Oct 2017, volume: 15, issue:10, pages: 1864 - 1868
Publisher: IEEE
 
» Meetings calendar
Abstract:
Provides a listing of future meetings.
Autors: Davide Fabiani;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Oct 2017, volume: 33, issue:5, pages: 60 - 62
Publisher: IEEE
 
» Memory Unscented Particle Filter for 6-DOF Tactile Localization
Abstract:
This paper addresses 6-DOF (degree-of-freedom) tactile localization, i.e., the pose estimation of tridimensional objects using tactile measurements. This estimation problem is fundamental for the operation of autonomous robots that are often required to manipulate and grasp objects whose pose is a priori unknown. The nature of tactile measurements, the strict time requirements for real-time operation, and the multimodality of the involved probability distributions pose remarkable challenges and call for advanced nonlinear filtering techniques. Following a Bayesian approach, this paper proposes a novel and effective algorithm, named memory unscented particle filter (MUPF), which solves 6-DOF localization recursively in real time by only exploiting contact point measurements. The MUPF combines a modified particle filter that incorporates a sliding memory of past measurements to better handle multimodal distributions, along with the unscented Kalman filter that moves the particles toward regions of the search space that are more likely with the measurements. The performance of the proposed MUPF algorithm has been assessed both in simulation and on a real robotic system equipped with tactile sensors (i.e., the iCub humanoid robot). The experiments show that the algorithm provides accurate and reliable localization even with a low number of particles and, hence, is compatible with real-time requirements.
Autors: Giulia Vezzani;Ugo Pattacini;Giorgio Battistelli;Luigi Chisci;Lorenzo Natale;
Appeared in: IEEE Transactions on Robotics
Publication date: Oct 2017, volume: 33, issue:5, pages: 1139 - 1155
Publisher: IEEE
 
» MEMS Logic Using Mixed-Frequency Excitation
Abstract:
We present multi-function microelectromechanical systems (MEMS) logic device that can perform the fundamental logic gate AND, OR, universal logic gates NAND, NOR, and a tristate logic gate using mixed-frequency excitation. The concept is based on exciting combination resonances due to the mixing of two or more input signals. The device vibrates at two steady states: a high state when the combination resonance is activated and a low state when no resonance is activated. These vibration states are assigned to logical value 1 or 0 to realize the logic gates. Using ac signals to drive the resonator and to execute the logic inputs unifies the input and output wave forms of the logic device, thereby opening the possibility for cascading among logic devices. We found that the energy consumption per cycle of the proposed logic resonator is higher than those of existing technologies. Hence, integration of such logic devices to build complex computational system needs to take into consideration lowering the total energy consumption. [2017-0041]
Autors: Saad Ilyas;Nizar Jaber;Mohammad I. Younis;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Oct 2017, volume: 26, issue:5, pages: 1140 - 1146
Publisher: IEEE
 
» Mexican Sign Language Alphanumerical Gestures Recognition using 3D Haar-like Features
Abstract:
The Mexican Sign Language (LSM) is a language of the deaf Mexican community, which consists of a series of gestural signs articulated by hands and accompanied with facial expressions. The lack of automated systems to translate signs from LSM makes integration of hearing-impaired people to society more difficult. This work presents a new method for LSM alphanumerical signs recognition based on 3D Haar-like features extracted from depth images captured by the Microsoft Kinect sensor. Features are processed with a boosting algorithm. To evaluate performance of our method, we recognized a set of signs from letters and numbers, and compared the results with the use of traditional 2D Haar-like features. Our system is able to recognize static LSM signs with a higher accuracy rate than the one obtained with widely used 2D features.
Autors: Javier Jimenez;Anabel Martin;Victor Uc;Arturo Espinosa;
Appeared in: IEEE Latin America Transactions
Publication date: Oct 2017, volume: 15, issue:10, pages: 2000 - 2005
Publisher: IEEE
 
» mGate: A Universal Magnetologic Gate for Design of Energy Efficient Digital Circuits
Abstract:
This paper presents a universal magnetologic gate, the so-called magnetogate (mGate) for the design of energy efficient digital circuits. The mGate employs magnetic tunnel junction (MTJ) cells, which have valuable features such as non-volatility, lower power consumption, and higher integration density compared with transistor-based gates. mGate can be efficiently exploited to the design of different combinational and sequential logic circuits. HSPICE-based simulations have been carried out to verify the correct functionality of different mGate-based circuits. The simulation results reveal that the mGate provides low area, power consumption, and energy while also offering more flexibility as compared with previously proposed MTJ-based designs.
Autors: Vahid Jamshidi;Mahdi Fazeli;Ahmad Patooghy;
Appeared in: IEEE Transactions on Magnetics
Publication date: Oct 2017, volume: 53, issue:10, pages: 1 - 13
Publisher: IEEE
 
» MicroCount: Free Software For Automated Microorganism Colony Counting By Computer
Abstract:
Counting of Bacterial Colony Forming is one of the primary techniques used in microbiology to quantify and isolate different groups of microorganisms. Despite being a time-consuming and laborious task, it is still predominantly performed manually. Most of automated solutions currently are developed for specific scenarios or has a high acquisition cost. It was developed new software for automated and manual colony count, through a rich set of image filter and computer vision techniques. Better result in microorganism identification were achieved a by improving the initial stages of the images processing, through filters that highlights image areas and sensibility control for segmentation routines. This improvement makes the software has no requisites on image acquiring way, differently of most current solutions. The integration of filters, segmentation and count techniques freely controlled by final user achieved better results than existing solutions.
Autors: Alisson Amorim Siqueira;Paulo Gustavo Serafim de Carvalho;
Appeared in: IEEE Latin America Transactions
Publication date: Oct 2017, volume: 15, issue:10, pages: 2006 - 2011
Publisher: IEEE
 
» Microfluidically Reconfigurable Microstrip Line Combline Filters With Wide Frequency Tuning Capabilities
Abstract:
Microfluidically repositionable selectively metallized plates (SMPs) are utilized for the first time to design and realize microstrip line combline filters with wide frequency tuning and high power-handling capability. A continuous frequency tuning range of 2.7:1 is achieved by utilizing tight coupling between the SMP and open-ended microstrip line resonators in order to change their length for tuning from 2.5 to 4 GHz and capacitively load one of their open ends for tuning from 1.5 to 2.5 GHz. The unloaded quality factor (Qu) of the resonators is maintained relatively constant (210–190) across the entire tuning range allowing for the low insertion loss (IL) and high power-handling capability. Specifically, a ~5% constant fractional bandwidth fourth-order filter design is discussed and experimentally verified. The filter exhibits less than 3-dB IL across the 2.7:1 tuning range. It is shown that the filter’s power handling capability can reach up to 15 W under constant average power excitation.
Autors: Timothy Palomo;Gokhan Mumcu;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Oct 2017, volume: 65, issue:10, pages: 3561 - 3568
Publisher: IEEE
 
» Microinhomogeneities in Semi-Insulating Cd(Zn)Te
Abstract:
We investigated the temperature dependences (TDs) in the range of 290–423 K for the Hall constant and the Hall carrier mobility () in semi-insulating Cd0.9 Zn0.1 Te:In (CZT) crystals. As-grown, CZT material has nonequilibrium distributions of native and impurity-related defects. Thus, before taking any measurements, the samples were kept inside the test chamber in the dark at 423 K to reach an equilibrium state at T < 423 K. For all the tested samples, the TD could be described by two activation energies. At the transitional point, the TD of the carrier mobility also changes from “normal” at high temperatures to “exponential” at low temperatures. The latter is a result of the collective effect of drift barriers due to microinhomogeneity. Therefore, only the high-temperature activation energies can be assigned to the ionization energies of the compensated deep donors (). For different samples, the values for (at absolute zero) were found to be in the range of 0.50–0.78 eV, and the degree of donor compensation []/[D] is between 0.3 and 0.98. The low-temperature region, where there are strong effects of crystal microinhomogeneities, cannot be used t- characterize the ionization energy of donors. Therefore, we describe the activation energy as , where is the drift barrier height found from the TD of the carrier mobility and takes a value close to unity. Values of for our studied samples lie within (0.05–0.35) eV.
Autors: P. Fochuk;Y. Nykoniuk;Z. Zakharuk;O. Kopach;N. Kovalenko;A. E. Bolotnikov;R. B. James;
Appeared in: IEEE Transactions on Nuclear Science
Publication date: Oct 2017, volume: 64, issue:10, pages: 2725 - 2728
Publisher: IEEE
 
» Microstructural Effects on Nickel Oxide Film Properties in an Infrared Electrochromic Window for Shutter-Less Infrared Sensor Application
Abstract:
Infrared electrochromic devices (ECDs) were fabricated and characterized in mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) ranges. They consisted of three layers with two metal electrodes. The layers were an ion storage layer, an ion conducting layer, and an electrochromic layer. As an ion storage layer, NiO film was used. To ensure higher performance of the ECDs, the microstructural and electrochromic properties of NiO films deposited at various sputtering pressures were investigated using SEM, X-ray photoelectron spectroscopy, and cyclic voltammetry. In addition, WO3 film and Ta2O5 film were used in the two types of fabricated devices as a cathodic electrochromic layer and an ion conducting layer, respectively. The transmittance values in the MWIR and LWIR ECDs were measured in colored and bleached states. The measured transmittance ratios of the colored state relative to the bleached state were 0.66 and 0.72 in the MWIR and LWIR ranges, respectively.
Autors: Hyun Bin Shim;Woo Young Kim;In-Ku Kang;Hee Chul Lee;
Appeared in: IEEE Sensors Journal
Publication date: Oct 2017, volume: 17, issue:20, pages: 6522 - 6528
Publisher: IEEE
 
» Microwave Annealing as a Low Thermal Budget Technique for ZnO Thin-Film Transistors Fabricated Using Atomic Layer Deposition
Abstract:
Microwave annealing (MWA) and furnace annealing are compared for their low thermal budget capability to improve the characteristics of ZnO-based thin-film transistors (TFTs). Both the ZnO channel and the Al2O3 gate dielectric are fabricated using atomic layer deposition. Using Si-wafer-susceptor assisted MWA with a substantial reduction of both annealing temperature and duration, significant improvements of the characteristics of the ZnO TFTs can be attained. A multi-step MWA process is found to further improve the characteristics of the TFTs. For the same microwave power and total duration, the field-effect mobility of the multi-step MWA TFT is 42% greater than that of the one-step MWA TFT with a similar sub-threshold swing. The multi-step MWA process can serve the purpose at temperatures as low as 220 °C.
Autors: Lei Yue;Chao-Chao Fu;Feng Sun;Zhi-Jun Qiu;Shi-Li Zhang;Dongping Wu;
Appeared in: IEEE Electron Device Letters
Publication date: Oct 2017, volume: 38, issue:10, pages: 1390 - 1393
Publisher: IEEE
 
» Microwave Imaging From Sparse Measurements for Near-Field Synthetic Aperture Radar
Abstract:
This paper reports the experimental studies for four image reconstruction methods from sparse measurement using wideband microwave synthetic aperture radar systems. The four methods include two denoising methods using zero filling (ZF) and nonuniform fast Fourier transform (NUFFT), and two compressed sensing (CS) methods using the orthogonal matching pursuit and the conjugate gradient algorithms. The specimens under test (SUTs) consist of a tray of small rocks with different densities with/without one piece wrapped in an aluminum foil. The raw measurements of the SUTs are randomly undersampled in the spatial domain, and the images are reconstructed from the measurements of 10%–60% sparse-sampling rates. The results show that the CS method achieves good image quality with as low as 30% sparse-sampling rate, while ZF and NUFFT require 50% to obtain acceptable quality. An enhanced Otsu’s method is also proposed to detect the foiled rock from sparse reconstructions, which improves detection performance for the sparse-sampling rate of 5%–15%. The reduction of spatial measurement leads to reduced cost or reduced measurement time.
Autors: Xiahan Yang;Yahong R. Zheng;Mohammad Tayeb Ghasr;Kristen M. Donnell;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Oct 2017, volume: 66, issue:10, pages: 2680 - 2692
Publisher: IEEE
 
» Microwave Microfluidic Sensor Based on a Microstrip Splitter/Combiner Configuration and Split Ring Resonators (SRRs) for Dielectric Characterization of Liquids
Abstract:
A microwave microfluidic sensor for dielectric characterization of liquids in real time is presented in this paper. The sensor is implemented in microstrip technology and consists of a symmetric splitter/combiner configuration loaded with a pair of identical split ring resonators (SRRs) and microfluidic channels placed on top of them (gap region). The sensor works in differential mode and sensing is based on frequency splitting. Thus, if the structure is unloaded or if it is symmetrically loaded with regard to the axial plane, only one transmission zero (notch) in the frequency response appears. However, if the axial symmetry is disrupted (e.g., by the presence of different liquids in the channels), two transmission zeros arise, and the difference in magnitude (notch depth) and frequency between such transmission zeros is indicative of the difference in the dielectric properties (complex dielectric constant). A circuit schematic, including transmission line sections to describe the distributed components, lumped elements to account for the SRRs and their coupling to the lines and lumped elements to model the liquid properties, is presented and validated. After proper calibration, the functionality of the proposed sensor is demonstrated by measuring the complex permittivity in solutions of deionized water and ethanol as a function of the ethanol content.
Autors: Paris Vélez;Lijuan Su;Katia Grenier;Javier Mata-Contreras;David Dubuc;Ferran Martín;
Appeared in: IEEE Sensors Journal
Publication date: Oct 2017, volume: 17, issue:20, pages: 6589 - 6598
Publisher: IEEE
 
» Microwave Photonic Filtering for Interrogating FBG-Based Multicore Fiber Curvature Sensor
Abstract:
We propose and experimentally demonstrate an approach to perform high-resolution and temperature-insensitive interrogation of a fiber Bragg grating (FBG)-based multicore fiber (MCF) curvature sensor using a microwave photonics filtering technique. By combining two reflected sample signals from the two FBGs inscribed in MCF and a dispersion device, a two-tap notch microwave photonic filter (MPF) is formed. The notch frequency of MPF is dependent on the time delay difference between the two FBG reflected signals, which is related to wavelength spacing of the two FBGs. Due to the wavelength spacing of the two FBGs is proportional to the curvature, the curvature can be readily interrogated by monitoring the notch frequency of MPF. The proposed interrogation scheme with the sensitivity of 92 MHz/ is achieved, whilst the sensitivity can be easily adjusted. Moreover, the proposed interrogation scheme is temperature insensitive.
Autors: Di Zheng;Javier Madrigal;David Barrera;Salvador Sales;Jose Capmany;
Appeared in: IEEE Photonics Technology Letters
Publication date: Oct 2017, volume: 29, issue:20, pages: 1707 - 1710
Publisher: IEEE
 
» Microwave Photonic Frequency Tripler Based on an Integrated Dual-Parallel Modulator Structure
Abstract:
A new technique for tripling the frequency of a microwave signal is presented. It is based on an integrated dual-parallel Mach–Zehnder modulator, which generates two orthogonally polarised RF modulated optical signals with different modulation indexes, and a polarisation-dependent optical attenuator. The photodetector output fundamental RF components generated by the two orthogonally polarised RF modulated optical signals have the same amplitude but an opposite phase, which are cancelled, leaving the frequency tripled microwave signal and the unwanted fifth order harmonic. The new frequency tripler has a simple structure, a wide bandwidth, and a high electrical spurious suppression ratio. Experimental results are presented demonstrating three times frequency multiplication of different-frequency microwave signals with electrical spurious suppression ratio of over 20 dB. The phase noise and the stability performance of the frequency tripler are also investigated experimentally.
Autors: Chongjia Huang;Hao Chen;Erwin Hoi Wing Chan;
Appeared in: IEEE Photonics Journal
Publication date: Oct 2017, volume: 9, issue:5, pages: 1 - 10
Publisher: IEEE
 
» Microwave Power System Based on a Combination of Two Magnetrons
Abstract:
Currently, microwave energy is utilized for many diverse industrial applications because of its various advantages including its eco-friendliness. Low-cost, high-efficiency, and high-power industrial microwave sources are in urgent demand. In this paper, we propose a low-cost quasi-coherent power-combining system based on a combination of two magnetrons. We have analyzed and built a low-loss waveguide-based applicator combined with specific phase. This system utilizes the coupling of the combiner to quasi-lock the slave magnetron. A waveguide phase shifter lies in the slave magnetron branch to adjust the phase difference between the master and slave magnetrons’ signals to achieve high resultant efficiency. Based on theory, the phase difference between the master and the injected slave magnetrons has been numerically calculated and analyzed. The phase difference changes periodically when the slave magnetron is quasi-locked to the master magnetron and the periodicity increases with the injection ratio. Experimental results show the resultant efficiency of the proposed system can reach as high as 92% when using several suitable waveguide components. The investigation also provides guidelines for further microwave power combination systems with multiple sources.
Autors: Yi Zhang;Kama Huang;Dinesh K. Agrawal;Tania Slawecki;Huacheng Zhu;Yang Yang;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Oct 2017, volume: 64, issue:10, pages: 4272 - 4278
Publisher: IEEE
 
» Microwave Sensors in Your Life [From the Guest Editors' Desk]
Abstract:
The articles in this special section addresses microwave sensor technology and discusses applications for its use. Radar sensors for military or automotive purposes and airport body scanners are examples that have gained wide interest, and the technology behind these has already been presented several times in the magazine. However, a significant number of microwave sensors used in our daily lives are not so well known to the average person because they are, for example, hidden behind walls or integrated into technical equipment.
Autors: Reinhard Knöchel;Christian Damm;W. Gregory Lyons;
Appeared in: IEEE Microwave Magazine
Publication date: Oct 2017, volume: 18, issue:6, pages: 24 - 25
Publisher: IEEE
 
» Microwave Thermal Emission Characteristics of a Two-Layer Medium With Rough Interfaces Using the Second-Order Small Perturbation Method
Abstract:
The second-order small perturbation method is applied to investigate brightness temperature corrections caused by the rough interfaces of a two-layer medium. The spectral weighting functions of the two rough interfaces are extracted from the solution, and their properties examined. It is found that the functions are identical for the two interfaces as the spectral variable approaches zero, indicating an identical weighting of the surface height variance on each interface and an additive effect on the brightness temperature at nadir. Sample results for some realistic scenarios show that surface roughness in a two-layer medium can increase or decrease the observed brightness temperature at shallower angles, and in the case of a wideband measurement, can shift the interference pattern in frequency.
Autors: R. J. Burkholder;J. T. Johnson;M. Sanamzadeh;L. Tsang;S. Tan;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Oct 2017, volume: 14, issue:10, pages: 1780 - 1784
Publisher: IEEE
 
» Microwave Tomography for Industrial Process Imaging: Example Applications and Experimental Results.
Abstract:
This article describes the implementation of microwave tomography for industrial process applications. Microwave tomography for industrial process imaging has different requirements from that for medical imaging. In addition to spatial resolution, high temporal resolution or real-time imaging is also important for high-speed processes, flows, or rapid reactions. Depending on the specific application, both quantitative imaging and qualitative imaging may be needed. Qualitative imaging would be sufficient to display distributions, patterns, or shapes, which may be adequate for some applications. Quantitative imaging would, however, be more informative, giving images with quantitative dielectric contrast or permittivity values from which other physical parameters, such as density, moisture content, and phase fraction, may be derived. With the microwave tomography approach described, several example applications in industrial processes are demonstrated, and a number of experimental imaging results are presented.
Autors: Zhipeng Wu;Haigang Wang;
Appeared in: IEEE Antennas and Propagation Magazine
Publication date: Oct 2017, volume: 59, issue:5, pages: 61 - 71
Publisher: IEEE
 
» Military Communications
Abstract:
The articles in this special section focus on military application communications.Information sharing is the key concept of network-centric military operations. As the complexity of operational environments increases, military communications networks must be agile to meet strict and evolving mission requirements in the midst of challenges presented by dynamic operational environments. The RF spectrum, for example, is a limited resource, which can be utilized better and in a more flexible way through the use of software defined networking and cognitive radios. Tactical communications encompasses all communication technologies used in the battlefield, constituting a heterogeneous collection of approaches and technologies. To assist in timely and accurate decision making, rapid information sharing is an important aspect of information superiority. Machine learning techniques can be used to analyze large streams of data, but military communications must ensure the security of the data and techniques.
Autors: Kevin S. Chan;Frank T. Johnsen;
Appeared in: IEEE Communications Magazine
Publication date: Oct 2017, volume: 55, issue:10, pages: 10 - 10
Publisher: IEEE
 
» Milking the Cache Cow With Fairness in Mind
Abstract:
Information-centric networking (ICN) is a popular research topic. At its heart is the concept of in-network caching. Various algorithms have been proposed for optimizing ICN caching, many of which rely on collaborative principles, i.e. multiple caches interacting to decide what to store. Past work has assumed altruistic nodes that will sacrifice their own performance for the global optimum. We argue that this assumption is insufficient and oversimplifies the reality. We address this problem by modeling the in-network caching problem as a Nash bargaining game. We develop optimal and heuristic caching solutions that consider both performance and fairness. We argue that only algorithms that are fair to all parties involved in caching will encourage engagement and cooperation. Through extensive simulations, we show our heuristic solution, FairCache, ensures that all collaborative caches achieve performance gains without undermining the performance of others.
Autors: Liang Wang;Gareth Tyson;Jussi Kangasharju;Jon Crowcroft;
Appeared in: IEEE/ACM Transactions on Networking
Publication date: Oct 2017, volume: 25, issue:5, pages: 2686 - 2700
Publisher: IEEE
 
» Millimeter-Wave Imaging of Surface-Breaking Cracks in Steel With Severe Surface Corrosion
Abstract:
Robust detection of surface-breaking (fatigue) cracks in metals with severe surface corrosion (rust) and pitting is of great practical interest. Detection of surface-breaking cracks in the millimeter-wave frequency range (30–300 GHz) has received considerable attention in the past two decades. At these frequencies, corrosion byproducts (rust) are in the family of dielectric materials allowing millimeter-wave signals to penetrate through and interact with a visually masked crack. When using open-ended rectangular waveguides, no contact is required, and the crack signal characteristics are significantly different than those from corrosion and pitting, which renders a crack detectable even in the presence of severe corrosion. Moreover, synthetic aperture radar images of cracks masked by corrosion can be rapidly generated providing additional geometrical information. This paper presents the results of uniquely combining these two methods for detecting cracks in severely corroded steel plates and for other similar applications where a crack is visually masked by a dielectric layer.
Autors: John R. Gallion;Reza Zoughi;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Oct 2017, volume: 66, issue:10, pages: 2789 - 2791
Publisher: IEEE
 
» MIMO Antenna Using Hybrid Electric and Magnetic Coupling for Isolation Enhancement
Abstract:
This paper presents a multiple-input and multiple-output antenna using a wideband decoupling structure for enhancing isolation. The decoupling structure is formed by a split ring, which consists of an inductive line and a capacitive gap to realize magnetic and electric coupling, respectively. By introducing the electric coupling in addition to the magnetic coupling, more degrees of freedom are obtained and the original coupling between antennas can be canceled out within a wide frequency band. Meanwhile, the performance of each antenna element is maintained, such as impedance bandwidth and radiation characteristics. Theoretical analysis and experimental verification are carried out. When the decoupling structure is placed between these two monopole antennas with edge-to-edge space of only 5 mm ( at 2.5 GHz), more than 20 dB isolation is realized over the bandwidth of 2.3–2.9 GHz (24%) with and less than −10 dB. Moreover, the isolation levels reach more than 30 dB over the frequency band of 2.3–2.8 GHz. Compared with the previous related works using decoupling networks and neutralization line techniques, the proposed decoupling structure can provide higher isolation of over 30 dB in a wider bandwidth.
Autors: Cheng-Dai Xue;Xiu Yin Zhang;Yun Fei Cao;Zhangju Hou;Chao Feng Ding;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Oct 2017, volume: 65, issue:10, pages: 5162 - 5170
Publisher: IEEE
 
» Minimal Perfect Hashing-Based Information Collection Protocol for RFID Systems
Abstract:
For large-scale RFID systems, this paper studies the practically important problem of target tag information collection, which aims at collecting information from a specific set of target tags instead of all. However, the existing solutions are of low time-efficiency because of two reasons. First, the serious collisions among tags due to hashing randomness seriously reduce the frame utilization, whose upper bound is just 36.8 percent. Second, they cannot efficiently distinguish the target tags from the non-target tags and thus inevitably collect a lot of irrelevant information on non-target tags, which further deteriorates the effective utilization of the time frame. To overcome the above two drawbacks, this paper proposes the minimal Perfect hashing-based Information Collection (PIC) protocol, which first leverages lightweight indicator vectors to establish a one-to-one mapping between target tags and slots, thereby improving the frame utilization to nearly 100 percent; and then uses the novel data structure called Minimal Perfect Hashing based Filter (MPHF) to filter out the non-target tags, thereby preventing them from interfering with the process of collecting information from target tags. Sufficient theoretical analyses are also presented in this paper to minimize the execution time of the proposed PIC protocol. Extensive simulations are conducted to compare the proposed PIC protocol with prior works side-by-side. The simulation results demonstrate that PIC significantly outperforms the state-of-the-art protocols in terms of time-efficiency.
Autors: Xin Xie;Xiulong Liu;Keqiu Li;Bin Xiao;Heng Qi;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Oct 2017, volume: 16, issue:10, pages: 2792 - 2805
Publisher: IEEE
 
» Minimizing Completion Time for Order Scheduling: Formulation and Heuristic Algorithm
Abstract:
In this study, the customer order scheduling problem is investigated to minimize total weighted completion time. A quadratic formulation is proposed to address this problem. This formulation is converted into an equivalent mixed-integer linear programming model by applying the linearization technique and the special structure of the problem. The problem size that can be solved to optimality is then investigated and reported based on the final linearized formulation. Furthermore, a hybrid nested partitions algorithm is developed to solve large-scale problems. Numerical results illustrate the advantages of the proposed model and demonstrate that the proposed algorithm can obtain high-quality solutions within a reasonable computational time.
Autors: Zhongshun Shi;Longfei Wang;Pai Liu;Leyuan Shi;
Appeared in: IEEE Transactions on Automation Science and Engineering
Publication date: Oct 2017, volume: 14, issue:4, pages: 1558 - 1569
Publisher: IEEE
 
» Minimum Description Length Sparse Modeling and Region Merging for Lossless Plenoptic Image Compression
Abstract:
This paper proposes a complete lossless compression method for exploiting the redundancy of rectified light-field data. The light-field data consist of an array of rectified subaperture images, called for short views, which are segmented into regions according to an optimized partition of the central view. Each region of a view is predictively encoded using a specifically designed sparse predictor, exploiting the smoothness of each color component in the current view, and the cross similarities with the other color components and already encoded neighbor views. The views are encoded sequentially, using a spiral scanning order, each view being predicted based on several similar neighbor views. The essential challenge for each predictor becomes choosing the most relevant regressors from a large number of possible regressors belonging to the neighbor views. The proposed solution here is to couple sparse predictor design and minimum description length (MDL) principle, where the data description length is measured by an implementable code length, optimized for a class of probability models. This paper introduces a region merging segmentation under the MDL criterion for partitioning the views into regions having their own specific sparse predictors. In experiments, several fast sparse design methods are considered. The proposed scheme is evaluated over a database of plenoptic images, achieving better lossless compression ratios than straightforward usage of standard image and video compression methods for the spiral sequence of views.
Autors: Petri Helin;Pekka Astola;Bhaskar Rao;Ioan Tabus;
Appeared in: IEEE Journal of Selected Topics in Signal Processing
Publication date: Oct 2017, volume: 11, issue:7, pages: 1146 - 1161
Publisher: IEEE
 
» Minimum Storage Regenerating Codes for All Parameters
Abstract:
Regenerating codes for distributed storage have attracted much research interest in the past decade. Such codes trade the bandwidth needed to repair a failed node with the overall amount of data stored in the network. Minimum storage regenerating (MSR) codes are an important class of optimal regenerating codes that minimize (first) the amount of data stored per node and (then) the repair bandwidth. Specifically, an - MSR code over stores a file consisting of symbols over among nodes, each storing symbols, in such a way that: 1) the file can be recovered by downloading the content of any of the nodes and 2) the content of any failed node can be reconstructed by accessing any of the remaining nodes and downloading symbols from each of these nodes. In practice, the file is typically available in uncoded form on some of the nodes, known as systematic nodes, and the defining node-repair condition above can be relaxed to requiring the optimal repair bandwidth for systematic nodes only. Such codes are called systematic–repair MSR codes. Unfortunately, finite– constructions of MSR codes are known only for certain special cases: either low rate, namely , or high repair connectivity, namely . Our main result in this paper is a finite– construction of systematic-repair MSR codes for all possible values of parameters . We also introduce a generalized construction for MSR codes to achieve the optimal repair bandwidth for all values of simultaneously.
Autors: Sreechakra Goparaju;Arman Fazeli;Alexander Vardy;
Appeared in: IEEE Transactions on Information Theory
Publication date: Oct 2017, volume: 63, issue:10, pages: 6318 - 6328
Publisher: IEEE
 
» Minimum-Cost Crowdsourcing with Coverage Guarantee in Mobile Opportunistic D2D Networks
Abstract:
With the remarkable proliferation of intelligent wireless devices and active mobile users, we have witnessed a rapid increasing trend of mobile crowdsourcing applications. While crowdsourcing does not depend on any specific underlying network, the device-to-device (D2D)-based crowdsourcing is highly desired when the originator of a crowdsourcing task cannot directly reach out to the participants or the conventional approaches for data transportation are costly. The marriage of crowdsourcing and D2D creates new, interesting research problems, mainly due to the unique non-deterministic setting in D2D. In this work, we focus on the problem of how to efficiently distribute a crowdsourcing task and recruit participants based on D2D communications. We formally formulate the minimum-cost crowdsourcing (MCC) problem in D2D networks, which explores a multi-dimensional design space to seek an optimal solution that minimizes the total crowdsourcing cost while satisfying the coverage probability over the field of interest. We introduce an approximation algorithm based on a reduced solution space and formally prove that its cost is bounded by a desired approximation ratio in comparison with the optimal solution. We further propose a lightweight online heuristic that inherits the same design philosophy but implements it in a distributed manner. We prototype the proposed online scheme in Android and carry out experiments in a campus environment, involving 21 Dell Streak tablets carried by students for a period of 15 days. We also extract the algorithm codes from our prototype and perform extensive simulations based on Haggle trace. The results demonstrate the efficiency of the proposed heuristics and reveal empirical insights into the design tradeoffs and practical considerations in D2D-based crowdsourcing.
Autors: Yanyan Han;Hongyi Wu;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Oct 2017, volume: 16, issue:10, pages: 2806 - 2818
Publisher: IEEE
 
» Mining Top-k Co-Occurrence Patterns across Multiple Streams
Abstract:
The recent Bigdata and IoT era has presented a number of applications that generate objects in a streaming fashion. It is well-known that real-time mining of important patterns from data streams support many domains. In retail markets and social network services, for example, such patterns are itemsets and words that frequently appear in many user-accounts, i.e., co-occurrence patterns. To efficiently monitor co-occurrence patterns, we address the novel problem of mining top-k closed co-occurrence patterns across multiple streams. We employ sliding window setting in this problem, and each pattern is ranked based on count, which is the number of streams that have generated the pattern. Since objects are consecutively generated and deleted, the count of a given pattern is dynamic, which may change the rank of the pattern. This renders a challenge to monitoring the top-k answer in real-time. We propose an index-based algorithm that addresses the challenge and provides the exact answer. Specifically, we propose the CP-Graph, a hybrid index of graph and inverted file structures. The CP-Graph can efficiently compute the count of a given pattern and update the answer while pruning unnecessary patterns. Our experimental study on real datasets demonstrates the efficiency and scalability of our solution.
Autors: Daichi Amagata;Takahiro Hara;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Oct 2017, volume: 29, issue:10, pages: 2249 - 2262
Publisher: IEEE
 
» Mission Critical Analysis and Design of IGBT-Based Power Converters Applied to Mine Hoist Systems
Abstract:
Mine hoist systems play a vital role in gold ore transportation. They are the connection between the underground mine and the beneficiation plant. As a result, any hoist system interruption compromises the production. In this paper, it is proposed a mission critical analysis and design methodology for power converters in order to achieve proper reliability of the hoist drive system. Since the failure of power devices is responsible for a significant portion of the total downtime of power converters, a detailed study of the insulated gate bipolar transistor (IGBT) power modules lifetime is carried out. The three level neutral-point-clamped and Active Neutral Point Clamped (ANPC) IGBT-based topologies are considered for this application. The recently presented Fault-Tolerant (FT)-ANPC converter is proposed as a higher reliability solution leading to longer power modules and drive system lifetimes. All the studies are based on practical operating data from a 900-m deep shaft hoist system operating in a gold mine in southeastern Brazil.
Autors: Victor de Nazareth Ferreira;Gabriel Alves Mendonça;Anderson Vagner Rocha;Robson Silva Resende;Braz de Jesus Cardoso Filho;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Oct 2017, volume: 53, issue:5, pages: 5096 - 5104
Publisher: IEEE
 

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