Electrical and Electronics Engineering publications abstract of: 11-2017 sorted by title, page: 8

» Exploit the Value of Production Data to Discover Opportunities for Saving Power Consumption of Production Tools
Abstract:
Semiconductor industry is both technology and energy intensive. There is a critical need to develop effective ways for energy saving to support smart and green production. This paper aims to develop data mining approach based on neural networks to exploit the value of production data and derive improvement directions for energy saving. In particular, the power consumption per wafer processed step (kilowatt hour per move, kwh/move) of individual production tool sets can be estimated, in which the relationships between kwh/move and 19 individual input factors, including “lot size,” “process time,” “uptime,” “usable machine,” “Q-time constrain,” and “sampling rate” are derived. An empirical study was conducted in a leading wafer fab and the results have shown practical viability of the proposed approach to discover effective opportunities for saving 17.21% power consumption by production tool sets.
Autors: Chih-Min Yu;Chen-Fu Chien;Chung-Jen Kuo;
Appeared in: IEEE Transactions on Semiconductor Manufacturing
Publication date: Nov 2017, volume: 30, issue:4, pages: 345 - 350
Publisher: IEEE
 
» Exploiting Experts’ Knowledge for Structure Learning of Bayesian Networks
Abstract:
Learning Bayesian network structures from data is known to be hard, mainly because the number of candidate graphs is super-exponential in the number of variables. Furthermore, using observational data alone, the true causal graph is not discernible from other graphs that model the same set of conditional independencies. In this paper, it is investigated whether Bayesian network structure learning can be improved by exploiting the opinions of multiple domain experts regarding cause-effect relationships. In practice, experts have different individual probabilities of correctly labeling the inclusion or exclusion of edges in the structure. The accuracy of each expert is modeled by three parameters. Two new scoring functions are introduced that score each candidate graph based on the data and experts’ opinions, taking into account their accuracy parameters. In the first scoring function, the experts’ accuracies are estimated using an expectation-maximization-based algorithm and the estimated accuracies are explicitly used in the scoring process. The second function marginalizes out the accuracy parameters to obtain more robust scores when it is not possible to obtain a good estimate of experts’ accuracies. The experimental results on simulated and real world datasets show that exploiting experts’ knowledge can improve the structure learning if we take the experts’ accuracies into account.
Autors: Hossein Amirkhani;Mohammad Rahmati;Peter J. F. Lucas;Arjen Hommersom;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Nov 2017, volume: 39, issue:11, pages: 2154 - 2170
Publisher: IEEE
 
» Exploiting the Maxwell-Wagner-Sillars Effect for Displacement-Current Phase Tomography of Two-Phase Flows
Abstract:
We introduce a method based on the Maxwell–Wagner–Sillars (MWS) effect to improve the performance of displacement-current phase tomography (DCPT) applied to two-phase flow imaging. DCPT utilizes as set of mutual admittance measurements between electrodes placed around a region of interest (RoI). This measurement can extract the phase of the displacement current between the electrodes so as to characterize the spatial distribution of the conductivity or dielectric loss inside the RoI. By exploiting the fact that the measured data at different frequencies will exhibit distinct MWS effects, the proposed approach can extract additional information from the measure data set and improve the resolution of DCPT for the imaging of two-phase flows. Numerical simulations along with experimental results illustrate the main findings of this paper.
Autors: Rafiul K. Rasel;Cagdas Gunes;Qussai M. Marashdeh;Fernando L. Teixeira;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7317 - 7324
Publisher: IEEE
 
» Exploring the Crystal Structure Space of CoFe2P by Using Adaptive Genetic Algorithm Methods
Abstract:
Advances in theoretical and computational condensed matter physics have opened the possibility to predict and design magnetic materials for specific technological applications. In this paper, we use the adaptive–genetic algorithm technique for exploring the low-energy crystal structure configurations of Co0.25Fe0.5P0.25, aiming to find new low-energy non-cubic phases with high saturation magnetization that might be interesting for high-performance permanent magnet development.
Autors: P. Nieves;S. Arapan;S. Cuesta-López;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» Exposing Approximate Computing Optimizations at Different Levels: From Behavioral to Gate-Level
Abstract:
Many classes of applications exhibit significant tolerance to inaccuracies in their computations. Some examples include image processing, multimedia applications, and machine learning. These inaccuracies can be exploited to build circuits with smaller area, lower power, and higher performance. Most previous work restricts the approximate optimizations to a particular level of abstraction or step within the VLSI process. This paper shows that a combined multilevel approach is far more superior. Thus, this paper exploits different optimizations visible only at each particular level, leading to better results than single-level methods. Moreover, approximate computing is highly data-dependent. Therefore, in this paper, we study the stability of the approximate circuits when the circuit is optimized for a particular data distribution and the final workload differs from it. Previous work mainly considers a single input data distribution and that this distribution is equal to the final workload. Results show that our proposed method can find better and more optimal configurations compared with previous work and can achieve circuits, which are more robust in environments with dynamic workloads.
Autors: Siyuan Xu;Benjamin Carrion Schafer;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Nov 2017, volume: 25, issue:11, pages: 3077 - 3088
Publisher: IEEE
 
» Extended Analysis of the $Z^{2}$ -FET: Operation as Capacitorless eDRAM
Abstract:
The Z2-FET operation as capacitorless DRAM is analyzed using advanced 2-D TCAD simulations for IoT applications. The simulated architecture is built based on actual 28-nm fully depleted silicon-on-insulator devices. It is found that the triggering mechanism is dominated by the front-gate bias and the carrier’s diffusion length. As in other FB-DRAMs, the memory window is defined by the ON voltage shift with the stored body charge. However, the Z2-FET’s memory state is not exclusively defined by the inner charge but also by the reading conditions.
Autors: Carlos Navarro;Joris Lacord;Mukta Singh Parihar;Fikru Adamu-Lema;Meng Duan;Noel Rodriguez;Binjie Cheng;Hassan El Dirani;Jean-Charles Barbe;Pascal Fonteneau;Maryline Bawedin;Campbell Millar;Philippe Galy;Cyrille Le Royer;Siegfried Karg;Paul Wells;Yong
Appeared in: IEEE Transactions on Electron Devices
Publication date: Nov 2017, volume: 64, issue:11, pages: 4486 - 4491
Publisher: IEEE
 
» Extraction of Front- and Rear-Interface Recombination in Silicon Double-Heterojunction Solar Cells by Reverse Bias Transients
Abstract:
We present a method, based upon reverse-recovery (RR) transient measurements, for determining the interface recombination parameters of double-sided heterojunction solar cells. A physics-based model is developed, and normalized parameters are used to provide results that can be scaled to arbitrary wafer thickness and minority-carrier diffusion coefficient. In the case of dominant recombination at only one interface, interface recombination velocity can be extracted directly from RR times. In devices with significant recombination at both interfaces, numerical modeling must be used. The effects of minority-carrier current spreading in small devices can be corrected for analytically. The results are then applied to both PEDOT/ n-Si and PEDOT/n-Si/TiO2 heterojunction cells. We find that the PEDOT/n-Si interface, despite favorable band offsets and a significant built-in voltage, is not an ideal hole injector because of recombination at the PEDOT/n-Si interface. We also find that the effective surface recombination velocity at the Si-TiO2 interface in a metallized device is 330 cm/s, confirming that the interface has a low defect density. Finally, we reflect on the significance of these results for the further development of silicon heterojunction cells.
Autors: Alexander H. Berg;Ken A. Nagamatsu;James C. Sturm;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Nov 2017, volume: 64, issue:11, pages: 4518 - 4525
Publisher: IEEE
 
» Fabrication and Characterization of MWCNT-Based Bridge Devices
Abstract:
Carbon nanotubes (CNTs) are one of the most actively researched structural materials due to their interesting electrical, mechanical, and chemical properties. Unlike single walled carbon nanotubes (SWCNTs), little work has been focused on multi-walled carbon nanotubes (MWCNTs) and their potential for practical devices. Here, we have fabricated bridge-shape devices integrating MWCNTs (> 50 nm in outer diameter) using three processes: optical lithography, electron beam-induced platinum deposition, and surface micromachining. Each device consists of a doubly-clamped nanotube suspended over gold electrodes on a highly conductive Si substrate. The suspended nanotubes are characterized individually using Raman spectroscopy and semiconductor parameters analysis and, overall, show, high crystallinity and low electrical resistance. The spring constants of doubly-clamped nanotubes were characterized using atomic force microscopy force−displacement measurements, with values as high as 70 N/m observed. Highly stiff MWCNTs are promising for a variety of applications, such as resonators and electrical interconnects. Through simulations, we estimate the resonance frequencies and pull-in voltages of these suspended nano-structures. The dependence of key parameters, such as the nanotube's length, Young's modulus, axial stress, and wall thickness is also discussed.
Autors: Karumbaiah N. Chappanda;Nitin M. Batra;Jorge A. Holguin-Lerma;Pedro M. F. J. Costa;Mohammad I. Younis;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Nov 2017, volume: 16, issue:6, pages: 1037 - 1046
Publisher: IEEE
 
» Fabrication and Evaluation of PCB-Embedded Broadband Signal Transformers With Custom Machined Racetrack-Shaped Ferrite Cores for Ethernet Applications
Abstract:
To reduce the manufacturing variability in broadband ferrite-core magnetic components such as ethernet transformers, there is great industry interest in the embedding of the core materials within a planar substrate and fabricating the windings using high-precision photolithography. An embedding process has been previously developed and found to impose design restrictions on embedded devices that can be feasibly fabricated. It was previously found that a racetrack core shape (toroidal halves joined by straight legs) allows the most efficient use of area to embed multiple magnetic devices with maximum inductance. In this paper, three different sizes of racetrack-shaped cores were fabricated from bulk ferrite. The racetrack cores were then embedded within printed circuit board substrate, wound as transformers, and measured to evaluate bandwidth and inductance. It was found that the transformer mutual inductance was significantly reduced through the embedding process. However, the devices were found to exhibit excellent broadband coupling behavior. Certain designs of transformers met the inductance and bandwidth requirements of 100 and 1000Base-T ethernet.
Autors: David Bowen;Debtanu Basu;Charles Krafft;Isaak Mayergoyz;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» Fabrication and Performance of Integrated Fluxgate for Current Sensing Applications
Abstract:
The recently developed Fluxgate technology from Texas Instruments has enabled the production of the industry’s first current sensing integrated circuit with a fully integrated fluxgate device and a compensation coil driver. This paper presents an overview of the Fluxgate technology, focusing on the fabrication and performance of the integrated magnetic field sensing device.
Autors: Dok Won Lee;Mona Eissa;Ann Gabrys;Byron Shulver;Erika Mazotti;Sudtida Lavangkul;Sopa Chevacharoenkul;Neal Murphy;Fuchao Wang;Yousong Zhang;Will French;Mark Jenson;Ricky Jackson;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» Fabrication and Photovoltaic Properties of Dye-Sensitized Solar Cells Based on Graphene–TiO2 Composite Photoelectrode With ZnO Nanowires
Abstract:
In this paper, the photoelectrode of dye-sensitized solar cell (DSSC) was fabricated into a double-layer structure on the fluorine-doped tin oxide glass, which was synthesized by a graphene oxide–titanium dioxide composite layer (GO–TiO2), and a zinc oxide nanowires (ZNWs) layer. The morphology and effects of double layer were investigated by the field emission scanning electron microscopy, UV-visible spectrometer, and solar simulator. The enhancement of the photovoltaic performances of DSSC could be attributed to the high specific surface area of GO and high electron mobility of zinc oxide. Besides, the equivalent circuit and electrochemical properties of GO–TiO2/ZNWs double structure were also investigated by electrochemical impedance spectroscopy.
Autors: Jung-Chuan Chou;Pei-Hong You;Yi-Hung Liao;Chih-Hsien Lai;Chia-Ming Chu;Yu-Jen Lin;Wan-Yu Hsu;Chang-Chia Lu;Yu-Hsun Nien;
Appeared in: IEEE Transactions on Semiconductor Manufacturing
Publication date: Nov 2017, volume: 30, issue:4, pages: 531 - 538
Publisher: IEEE
 
» Fairness-Aware Spectral and Energy Efficiency in Spectrum-Sharing Wireless Networks
Abstract:
This paper introduces a fair and energy-efficient resource allocation framework in spectrum-sharing wireless networks with quality-of-service guarantees. Consider the tradeoff between energy efficiency and spectral efficiency, the multiobjective problem of spectral efficiency and energy efficiency is transformed into a problem that minimizes the total power consumption and maximizes the achievable utility, subject to power constraints and rate outage probability constraints. We then analyze the complexity of the considered problem; particularly, the optimization problem is NP-Hard when and and is convex for other values of the fairness index . After that, we adopt the successive convex approximation (SCA) approach to approximate and transform the NP-hard nonconvex optimization problem into a sequence of convex programs and propose two iterative SCA-based resource allocation algorithms. Extensive simulation results are presented to demonstrate the effectiveness and outperformance of the proposed algorithms over existing frameworks.
Autors: Quoc-Viet Pham;Won-Joo Hwang;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Nov 2017, volume: 66, issue:11, pages: 10207 - 10219
Publisher: IEEE
 
» Fall Detection Utilizing Frequency Distribution Trajectory by Microwave Doppler Sensor
Abstract:
Falls are serious issues encountered in the lives of the elderly living alone. Since the elderly cannot stand up without support from a caregiver, or because they may lose consciousness after falling, they may remain on the floor for an extended period of time after a fall; this leads to serious complications including hypothermia, dehydration, and sometimes, even death. Therefore, immediate detection of falls is necessary. In this paper, we propose a fall detection system based on a microwave Doppler sensor. In the proposed system, we apply the frequency distribution trajectories corresponding to the velocities of the movements while falling, to a hidden Markov model. In order to evaluate the proposed system, we carry out verification experiments for three types of fall events (tripping, slipping, and fainting) and four types of non-fall events (walking, bending, sitting, and standing). From the results, the accuracy, positive predictive value, and negative predictive value are found to be 0.95, 0.94, and 0.97, respectively.
Autors: Kazuaki Shiba;Takashi Kaburagi;Yosuke Kurihara;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7561 - 7568
Publisher: IEEE
 
» Faraday Effect in Bi-Periodic Photonic-Magnonic Crystals
Abstract:
We present a theoretical investigation of the polarization plane rotation at light transmission—Faraday effect, through 1-D multilayered magneto-photonic systems consisting of periodically distributed magnetic and dielectric layers. We calculate Faraday rotation (FR) spectra of photonic-magnonic crystals, where cell (or supercell) is composed of magnetic layer and dielectric layer (or section of dielectric photonic crystal). We found that the FR of p-polarized incident light is increasing in the transmission band with the number of magnetic supercells. The increase of FR is observed also in vicinity of the band-gap modes localized in magnetic layers but the maximal polarization plane rotation angles are reached at minimal transmittivity. We show that presence of linear magneto-electric interaction in the magnetic layers leads to significant increase of the FR angles of s-polarized incident light in the vicinity of the fine-structured modes inside the photonic-band-gap.
Autors: Yuliya S. Dadoenkova;Nataliya N. Dadoenkova;Igor L. Lyubchanskii;Jarosław W. Kłos;Maciej Krawczyk;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» Fast Algorithm and VLSI Architecture of Rate Distortion Optimization in H.265/HEVC
Abstract:
In H.265/high efficiency video coding (HEVC) encoding, rate distortion optimization (RDO) is an important cost function for mode decision and coding structure decision. Despite being near-optimum in terms of coding efficiency, RDO suffers from a high complexity. To address this problem, this paper presents a fast RDO algorithm and its very large scale implementation (VLSI) for both intra- and inter-frame coding. The proposed algorithm employs a quantization-free framework that significantly reduces the complexity for rate and distortion optimization. Meanwhile, it maintains a low degradation of coding efficiency by taking the syntax element organization and probability model of HEVC into consideration. The algorithm is also designed with hardware architecture in mind to support an efficient VLSI implementation. When implemented in the HEVC test model, the proposed algorithm achieves 62% RDO time reduction with 1.85% coding efficiency loss for the “all-intra” configuration. The hardware implementation achieves 1.6 × higher normalized throughput relative to previous works, and it can support a throughput of 8k@30fps (for four fine-processed modes per prediction unit) with 256 k logic gates when working at 200 MHz.
Autors: Heming Sun;Dajiang Zhou;Landan Hu;Shinji Kimura;Satoshi Goto;
Appeared in: IEEE Transactions on Multimedia
Publication date: Nov 2017, volume: 19, issue:11, pages: 2375 - 2390
Publisher: IEEE
 
» Fast and Fully Automatic Left Ventricular Segmentation and Tracking in Echocardiography Using Shape-Based B-Spline Explicit Active Surfaces
Abstract:
Cardiac volume/function assessment remains a critical step in daily cardiology, and 3-D ultrasound plays an increasingly important role. Fully automatic left ventricular segmentation is, however, a challenging task due to the artifacts and low contrast-to-noise ratio of ultrasound imaging. In this paper, a fast and fully automatic framework for the full-cycle endocardial left ventricle segmentation is proposed. This approach couples the advantages of the B-spline explicit active surfaces framework, a purely image information approach, to those of statistical shape models to give prior information about the expected shape for an accurate segmentation. The segmentation is propagated throughout the heart cycle using a localized anatomical affine optical flow. It is shown that this approach not only outperforms other state-of-the-art methods in terms of distance metrics with a mean average distances of 1.81±0.59 and 1.98±0.66 mm at end-diastole and end-systole, respectively, but is computationally efficient (in average 11 s per 4-D image) and fully automatic.
Autors: João Pedrosa;Sandro Queirós;Olivier Bernard;Jan Engvall;Thor Edvardsen;Eike Nagel;Jan D’hooge;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Nov 2017, volume: 36, issue:11, pages: 2287 - 2296
Publisher: IEEE
 
» Fast and Robust Self-Representation Method for Hyperspectral Band Selection
Abstract:
In this paper, a fast and robust self-representation (FRSR) method is proposed to select a proper band subset from hyperspectral imagery (HSI). The FRSR assumes the separability structure of the HSI band set and transforms the problem of separable nonnegative matrix factorization into the robust self-representation (RSR) model. Then, the FRSR incorporates structured random projections into the RSR model to improve computational efficiency. The solution of FRSR is formulated into optimizing a convex problem and the augmented Lagrangian multipliers are adopted to estimate the proper factorization localizing matrix in the FRSR. The selected band subset is constituted with the bands corresponding to the r largest diagonal entries of the factorization localizing matrix. The experimental results show that FRSR outperforms state-of-the-art techniques in classification accuracy with lower computational cost.
Autors: Weiwei Sun;Long Tian;Yan Xu;Dianfa Zhang;Qian Du;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Nov 2017, volume: 10, issue:11, pages: 5087 - 5098
Publisher: IEEE
 
» Fast Convergence Rates for Distributed Non-Bayesian Learning
Abstract:
We consider the problem of distributed learning, where a network of agents collectively aim to agree on a hypothesis that best explains a set of distributed observations of conditionally independent random processes. We propose a distributed algorithm and establish consistency, as well as a nonasymptotic, explicit, and geometric convergence rate for the concentration of the beliefs around the set of optimal hypotheses. Additionally, if the agents interact over static networks, we provide an improved learning protocol with better scalability with respect to the number of nodes in the network.
Autors: Angelia Nedić;Alex Olshevsky;César A. Uribe;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Nov 2017, volume: 62, issue:11, pages: 5538 - 5553
Publisher: IEEE
 
» Fast Intra Bunch Train Charge Feedback for FELs Based on Photo Injector Laser Pulse Modulation
Abstract:
Bunch charge variations in free electron lasers such as the free electron laser (FEL) in Hamburg (FLASH) or the European X-ray FEL (E-XFEL) impact the longitudinal phase space distribution of the electrons resulting in different bunch peak currents, bunch durations, and bunch shapes. The electron bunches are generated by short ultraviolet (UV) laser pulses impinging onto a photocathode inside a radio frequency (RF) accelerating cavity. At FLASH, bursts of bunches up to 800 pulses with an intra train repetition rate of 1 MHz are used and even higher repetition rates (up to 4.5 MHz) are planned at the E-XFEL. Charge variations along these bunch trains can be caused by variations of the laser pulse energies, instabilities of the accelerating fields in the RF cavity, and time-dependent effects in the photoemission process. To improve the intra bunch train charge flatness and to compensate train-to-train fluctuations, a dedicated digital control system, based on the Micro Telecommunication Computing Architecture (MicroTCA.4) standard, was designed, implemented, and successfully tested at FLASH. The system consists of a bunch charge detection module which analyzes data from a toroid system and provides the input signal for the controller which drives a fast UV Pockels cell installed in the optical path of the photocathode laser. The Pockels cell alters the laser polarization and thus the transmission through a polarizer. The modulation of UV laser pulse energy with an iterative learning feedforward minimizes the repetitive errors from bunch train to bunch train. A fast feedback algorithm implemented in a field-programmable gate array allows for fast tuning of bunch charge inside the bunch train. In this paper, a detailed description of the system and the first preliminary measurement results are presented.
Autors: Tomasz Kozak;Bernd Steffen;Sven Pfeiffer;Siegfried Schreiber;Andrzej Napieralski;
Appeared in: IEEE Transactions on Nuclear Science
Publication date: Nov 2017, volume: 64, issue:11, pages: 2904 - 2910
Publisher: IEEE
 
» Fast Optical Flow Estimation Without Parallel Architectures
Abstract:
According to recent results on Middlebury, MPI Sintel, and KITTI benchmarks, the accuracy of optical flow estimation algorithms has been significantly improved. The speed of them, however, has been too slow to meet the requirement of real-time applications. As a result, some parallel architectures (such as FPGA or GPU) have to be used for accelerating. Therefore, reducing the computational cost of optical flow estimation makes a lot of sense. To overcome the above issues, this paper proposes a fast local method based on 3D-gradients and approximate nearest-neighbor field (NNF), which is different from the widely used global model. In our method, NNF is used to provide initial optical flow field, and the proposed fast 3D-gradients-based local operator is used to propagate flow from coarse level to finer level in the coarse-to-fine refinement. We implement two versions of our method (with/without NNF initialization). Experimental results show that our method has a significant advantage for speed over other methods, where the fast version is capable of processing sequence () at frames/s without parallel architectures. Meanwhile, our accuracy is also within acceptable levels on both small and large motion for some real-time applications.
Autors: En Zhu;Yuanwei Li;Yanling Shi;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Nov 2017, volume: 27, issue:11, pages: 2322 - 2332
Publisher: IEEE
 
» Fast Software Implementations of Bilinear Pairings
Abstract:
Advancement in pairing-based protocols has had a major impact on the applicability of cryptography to the solution of more complex real-world problems. However, the computation of pairings in software still needs to be optimized for different platforms including emerging embedded systems and high-performance PCs. Few works in the literature have considered implementations of pairings on the former applications despite their growing importance in a post-PC world. In this paper, we investigate the efficient computation of the Optimal-Ate pairing over special class of pairing friendly Barreto-Naehrig curves in software at different security levels. We target both applications and perform our implementations on ARM-powered processors (with and without NEON instructions) and PC processors. We exploit state-of-the-art techniques and propose new optimizations to speed up the computation in the different levels including tower field and curve arithmetic. In particular, we extend the concept of lazy reduction to inversion in extension fields, analyze an efficient alternative for the sparse multiplication used inside the Miller’s algorithm and reduce further the cost of point/line evaluation formulas in affine and projective homogeneous coordinates. In addition, we study the efficiency of using M-type and D-type sextic twists in the pairing computation and carry out a detailed comparison between affine, Jacobian, and homogeneous coordinate systems. Our implementations on various mass-market emerging embedded devices significantly improve the state-of-the-art of pairing computation on ARM-powered devices and x86-64 PC platforms. For ARM implementations we achieved considerably faster computations in comparison to the counterparts.
Autors: Reza Azarderakhsh;Dieter Fishbein;Gurleen Grewal;Shi Hu;David Jao;Patrick Longa;Rajeev Verma;
Appeared in: IEEE Transactions on Dependable and Secure Computing
Publication date: Nov 2017, volume: 14, issue:6, pages: 605 - 619
Publisher: IEEE
 
» Fast Spectral Clustering With Anchor Graph for Large Hyperspectral Images
Abstract:
The large-scale hyperspectral image (HSI) clustering problem has attracted significant attention in the field of remote sensing. Most traditional graph-based clustering methods still face challenges in the successful application of the large-scale HSI clustering problem mainly due to their high computational complexity. In this letter, we propose a novel approach, called fast spectral clustering with anchor graph (FSCAG), to efficiently deal with the large-scale HSI clustering problem. Specifically, we consider the spectral and spatial properties of HSI in the anchor graph construction. The proposed FSCAG algorithm first constructs anchor graph and then performs spectral analysis on the graph. With this, the computational complexity can be reduced to , which is a significant improvement compared to conventional graph-based clustering methods that need at least , where , , and are the number of samples, features, and anchors, respectively. Several experiments are conducted to demonstrate the efficiency and effectiveness of the proposed FSCAG algorithm.
Autors: Rong Wang;Feiping Nie;Weizhong Yu;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Nov 2017, volume: 14, issue:11, pages: 2003 - 2007
Publisher: IEEE
 
» Fast Successive-Cancellation Decoding of Polar Codes: Identification and Decoding of New Nodes
Abstract:
The decoding latency of polar codes can be reduced by implementing fast parallel decoders in the last stages of decoding. In this letter, we present five such decoders corresponding to different frozen-bit sequences to improve the decoding speed of polar codes. Implementing them achieves significant latency reduction without tangibly altering the bit-error-rate performance of the code.
Autors: Muhammad Hanif;Masoud Ardakani;
Appeared in: IEEE Communications Letters
Publication date: Nov 2017, volume: 21, issue:11, pages: 2360 - 2363
Publisher: IEEE
 
» Fast Uplink Synchronization in LTE-Like Systems
Abstract:
We show a way to accelerate the successive multiuser detection (SMUD) algorithm for initial uplink synchronization (IUS) in an LTE-like system. We develop a new data model to pose IUS as a signal representation problem in a Fourier basis. We provide the theoretical guidelines for generating codes using the data model. Our method significantly reduces the complexity of computationally demanding multiplication steps of the SMUD algorithm.
Autors: Md Mashud Hyder;Kaushik Mahata;
Appeared in: IEEE Communications Letters
Publication date: Nov 2017, volume: 21, issue:11, pages: 2424 - 2427
Publisher: IEEE
 
» Fast- and Low-Complexity atan2(a,b) Approximation [Tips and Tricks]
Abstract:
This article presents a new entry to the class of published algorithms for the fast computation of the arctangent of a complex number. Our method uses a look-up table (LUT) to reduce computational errors. We also show how to convert a large-sized LUT addressed by two variables to an equivalent-performance smaller-sized LUT addressed by only one variable. In addition, we demonstrate how and why the use of follow-on LUTs applied to other simple arctan algorithms produce unexpected and interesting results.
Autors: Vicente Torres;Javier Valls;Richard Lyons;
Appeared in: IEEE Signal Processing Magazine
Publication date: Nov 2017, volume: 34, issue:6, pages: 164 - 169
Publisher: IEEE
 
» Fatigue-Aware Management of Cellular Networks Infrastructure with Sleep Modes
Abstract:
We consider the problem of controlling the rate of failures triggered by fatigue processes of Base Stations (BSs) in cellular networks subject to Sleep Modes (SMs). Specifically, the increase of time spent in SM tends to decrease the BS failure rate by following, e.g., the Arrhenius law. However, the transitions between the power states tend to increase the BS failure rate, which can be predicted by the Coffin-Manson model. In this context, the energy savings triggered by SMs would not be economically useful if the BS failure rate were increased too much. Our goal is therefore to tackle the problem of minimizing the BS failure rate in a cellular network subject to SMs. After showing that the optimal formulation of the problem is NP-Hard, we propose a new algorithm, named LIFE, to practically solve it. We run LIFE on different scenarios (driven by LTE and legacy UMTS technologies). Our results show that LIFE outperforms two previous energy-aware algorithms, which instead do not take into account the BS failure rate. Specifically, our solution is able to achieve up to 40 percent of power saving at night, without a strong penalty in the BS failure rate.
Autors: Luca Chiaraviglio;Francesca Cuomo;Marco Listanti;Edoardo Manzia;Martina Santucci;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Nov 2017, volume: 16, issue:11, pages: 3028 - 3041
Publisher: IEEE
 
» FDA approves a prescription-only app for addiction [News]
Abstract:
Drug and alcohol users will soon be able to get a prescription for a mobile app that could help them stay clean. Developed by Pear Therapeutics in Boston and San Francisco, the app helps people recovering from addiction stay on track while participating in outpatient treatment. The U.S. Food and Drug Administration (FDA) approved the prescription-only software in September.
Autors: Emily Waltz;
Appeared in: IEEE Spectrum
Publication date: Nov 2017, volume: 54, issue:11, pages: 9 - 10
Publisher: IEEE
 
» Fe2O3–SiO2 Core–Shell Nanoparticles Conjugated With Bovine Serum Albumin
Abstract:
This paper presents a systematic study of bovine serum albumin (BSA) conjugation on the amine-functionalized magnetic nanoparticles (MNPs) and the effects of various experimental parameters on the conjugation process. The amine-functionalized Fe2O3 NPs with silica shell were synthesized through surface modification. The BSA conjugation on the amine-functionalized Fe2O3 NPs was achieved through covalent binding via carbodiimide activation. Morphology and magnetic properties of the nanoparticles were investigated. The influence of reaction time, the initial protein concentration, and the temperature on BSA conjugation was studied. The increased reaction time promoted the conjugation of BSA on the Fe2O3 NPs and finally reached the saturation at 43.4 mg/g. The initial BSA concentration can increase the amount of conjugated BSA. The temperature exhibited no significant effect on the conjugation process. The results are useful for designing effective fabrication strategy for protein-conjugated nanomaterials.
Autors: Yun Teng;Philip W. T. Pong;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» Feasibility of Single-Beam Interference Alignment in Multi-Carrier Interference Channels
Abstract:
Sun and Luo recently showed that if the vector-space single-beam interference alignment problem for a -user, -carrier interference channel is feasible, then . We prove the converse, that if , then the problem is feasible, i.e., that the requisite beamformers do exist.
Autors: David Grant;Mahesh K. Varanasi;
Appeared in: IEEE Transactions on Information Theory
Publication date: Nov 2017, volume: 63, issue:11, pages: 7352 - 7357
Publisher: IEEE
 
» FeCoNi-Coated Glass Fabric/Polycarbonate Composite Sheets for Electromagnetic Absorption and Shielding
Abstract:
In order to evaluate the electromagnetic (EM) absorption and shielding effects in near-field and far-field regions, the FeCoNi-coated glass fabric/polycarbonate composite sheets were fabricated. The composite sheets were composed of the laminated structure, which has one or two ply-FeCoNi-coated glass fabrics with or without Ni grid in polymer matrix. The evaluation of EM absorption and shielding behaviors was measured by using a microstrip line and a shielded loop antenna, which is based on IEC62333 in near field and rectangular waveguide at the X-band region in the far-field region. The power absorptions were up to about 86% at 10 GHz. The inter-decoupling effect for FeCoNi-coated glass fabric with Ni grid in composite exhibited about 45 dB at around 1.3 GHz, which is comparable to that of a conductive Cu foil. The shielding effectiveness was obtained over 70 dB at the X-band region for FeCoNi-coated glass fabric with Ni grid composite sheets.
Autors: Joonsik Lee;Byung Mun Jung;Sang Bok Lee;Sang-Kwan Lee;Ki Hyeon Kim;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» Feedback Stability of Negative Imaginary Systems
Abstract:
This paper extends the robust feedback stability theorem of negative imaginary systems by removing restrictive assumptions on the instantaneous gains of the systems that were imposed in the earlier literature, and it further generalizes this robust analysis result into the case that allows negative imaginary systems to have poles at the origin. In doing so, we extend the class of negative imaginary systems for which this robust stability theorem is applicable. We also show that this new generalized necessary and sufficient result specializes to the earlier theorems under the same assumptions. We additionally prove that the previously known dc gain condition is not only necessary and sufficient for robust feedback stability under the earlier specified instantaneous gain assumptions, but is also necessary and sufficient for robust feedback stability under new, different and equally simple assumptions. The general robust feedback stability theorem for negative imaginary systems with free body dynamics (i.e., poles at the origin) derived in this paper also specializes to the case that is only applicable for the negative imaginary system without poles at the origin. Since the results for negative imaginary systems with free body dynamics developed in this paper depend on the existence of a matrix with certain properties, we also propose a systematic construction of this matrix and show that construction of one such is sufficient for determining the feedback stability of the closed-loop system. Finally, examples are used to demonstrate the applicability of the results.
Autors: Alexander Lanzon;Hsueh-Ju Chen;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Nov 2017, volume: 62, issue:11, pages: 5620 - 5633
Publisher: IEEE
 
» FEM-Simulation and Experimental Realization of Low-Cost Electrowetting Actuators for a Flexible Microfluidic Pixel
Abstract:
We investigate and characterize three different fabrication methods facilitating low-cost electrowetting-on-dielectric (EWOD) structures. EWOD allows setting fluid droplets in motion by electrically altering the surface tension equilibrium at the triple contact line. We present a fabrication method for flexible EWOD structures by screen printing a transparent and conducting poly (3, 4-ethylenedioxythiophene) polystyrene sulfonate (PDOT:PSS) polymer on polyethylene terephthalate (PET) foil. As a demonstrator for applications, i.e., a flexible microfluidic EWOD display cell is simulated using FEM and characterized in terms of feasibility and response speed for various pixel scaling. The accordingly fabricated microfluidic pixel serves as a basis cell for a bendable and flexible EWOD cell multigrid, where all pixels are directly addressable.
Autors: Andreas Tröls;Herbert Enser;Bernhard Jakoby;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7273 - 7280
Publisher: IEEE
 
» Femtosecond Laser Inscription of Fiber Bragg Grating in Twin-Core Few-Mode Fiber for Directional Bend Sensing
Abstract:
We demonstrated femtosecond laser inscription of fiber Bragg gratings (FBGs) in a twin-core few-mode fiber (TC-FMF) for directional bend sensing. An FBG was selectively inscribed in one core of the TC-FMF by using an 800 nm femtosecond laser through a phase mask. Three resonance peaks at the wavelengths of 1549.05, 1547.65, and 1546.08 nm were observed in the reflection spectrum of the TC-FM FBG, and were generated by the LP01 mode resonance, LP01-LP11 mode cross-coupling resonance, and LP11 mode resonance, respectively. Moreover, the TC-FM FBG exhibited the capability of directional bend sensing and achieved a maximum bend sensitivity of -37.41 pm/m-1. Hence, the proposed TC-FM FBG directional bend sensors could further be developed as promising solutions for detecting vectorial seismic or acoustic waves and 3-D shape sensing.
Autors: Kaiming Yang;Jun He;Changrui Liao;Ying Wang;Shen Liu;Kuikui Guo;Jiangtao Zhou;Zhengyong Li;Zhan Tan;Yiping Wang;
Appeared in: Journal of Lightwave Technology
Publication date: Nov 2017, volume: 35, issue:21, pages: 4670 - 4676
Publisher: IEEE
 
» Femtosecond Laser Pulse-Induced Perpendicular Magnetization in Co Ultrathin Films With Diverse Surroundings
Abstract:
Laser-induced irreversible modifications of magnetic properties of molecular beam epitaxy grown X/Co/Y trilayers on Al2O3 substrates were investigated, with combinations of nonmagnetic metals Pt and Au as buffer X and capping layer Y. It is shown that the formation of regions with irreversibly rotated magnetization from in-plane to out-of-plane orientation occurred for Pt/Co/Pt, Pt/Co/Au, and Au/Co/Pt trilayers. In the Au/Co/Au system, the modification of magnetic properties was negligible. Pt/Co/Pt trilayers were also deposited by sputtering on Si/SiO2 substrates. In this case, a significant suppression of laser-induced magnetic modifications was observed and correlated with the lower thermal conductivity of the Si/SiO2 substrate.
Autors: Jan Kisielewski;Iosif Sveklo;Zbigniew Kurant;Dmitriy Mitin;Manfred Albrecht;Andrzej Wawro;Andrzej Maziewski;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» Femtosecond Laser-Induced Magnetization Reversal Domain of Co-Sublattice in TbCo Film
Abstract:
All-optical switching (AOS) is an emerging recording technology by using femtosecond laser to manipulate the ultrafast magnetization reversal for future super high density magnetic storage. TbCo films possess a ferrimagnetic structure and large perpendicular anisotropy and, thus, become a potential material for AOS. In this paper, we simulate the ultrafast magnetization reversal domain of Co-sublattice in TbCo films under 100 fs pulse laser with a general theoretical framework, and our simulation results show that TbCo films irradiated with a higher power fluence laser have a larger reversal domain of Co-sublattice due to the higher peak temperature and the further critical isotherm of electrons. Moreover, high Co content can help Co-sublattice form a large reversal domain, but is unable to obtain the highly uniform reversal domain perhaps attributed to the insufficient anti-ferromagnetic interaction between Tb atoms and Co atoms.
Autors: Weiming Cheng;Xing Li;Yajuan Hui;Kaifeng Dong;Haiwei Wang;Jincai Chen;Changsheng Xie;Xiangshui Miao;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» FengYun-3C VIRR Active Fire Monitoring: Algorithm Description and Initial Assessment Using MODIS and Landsat Data
Abstract:
The Visible and Infra-Red Radiometer (VIRR) is an improved third-generation earth observation sensor that has channels ranging from the visible to thermal bands and is carried on board the Chinese FengYun-3C satellite. The VIRR instrument provides full global coverage at a spatial resolution of 1 km. It is neither appropriate nor correct to simply duplicate the parameters used in algorithms designed for other sensors. Hence, this paper proposes an active fire-monitoring algorithm designed for the VIRR sensor. A newly proposed concept—the “infrared channel slope”—is employed in the algorithm, which can detect active fire pixels by identifying deviations in their mid-infrared and thermal infrared brightness temperatures. “Dynamic thresholds” are also used to allow the algorithm to adapt to different situations. Different fire events that occurred in different parts of the world between 2014 and 2016 are selected to test the robustness of the algorithm. The testing consists of two parts: a rough assessment using products of a similar spatial resolution and then a detailed assessment based on fine spatial resolution images. In the rough assessment part, the results are compared with the Moderate Resolution Imaging Spectroradiometer (MODIS) Fire and Thermal Anomaly product (MOD14A1) and the China Meteorological Administration’s Global Fire References (GFR) products from the National Satellite Meteorological Center. In the detailed assessment, imagery acquired by the Landsat-7/Enhanced Thematic Mapper Plus and the Landsat-8/Operational Land Imager is used. The MODIS and Landsat data are utilized as reference data to validate the accuracy while the comparison with the GFR products is carried out to demonstrate the advantages of this method. The assessment demonstrates that the algorithm produces comparable results to those obtained using MOD- 4A1 and is a significant improvement compared with GFR.
Autors: Zhengyang Lin;Fang Chen;Bin Li;Bo Yu;Zeeshan Shirazi;Qinchun Wu;Wei Wu;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Nov 2017, volume: 55, issue:11, pages: 6420 - 6430
Publisher: IEEE
 
» Ferroelectric Oscillators and Their Coupled Networks
Abstract:
We propose ferroelectric field-effect transistor (FEFET)-based realization of non-linear, relaxation oscillators and their coupled networks. To control oscillations, we utilize a unique physics of FEFETs: the dynamic voltage controllabilityof the location and the width of the hysteresis loop. Such ferroelectric-basedcomplex, dynamical systems can lead to efficient physical platforms for alternative and neuromorphic computing paradigms.
Autors: Zheng Wang;Sourabh Khandelwal;Asif Islam Khan;
Appeared in: IEEE Electron Device Letters
Publication date: Nov 2017, volume: 38, issue:11, pages: 1614 - 1617
Publisher: IEEE
 
» Ferromagnetic L10 Phase Formation in the Mn–Al–C Alloys Induced by High-Pressure Spark Plasma Sintering
Abstract:
Structural and magnetic characterization of Mn–Al–C permanent magnets obtained by spark plasma sintering (SPS) is reported. The transformation from the parent -phase to the ferromagnetic -phase occurs simultaneously with the process of sintering. The use of a tungsten carbide crucible enabled us to decrease the sintering temperature, which hampered the precipitation of secondary phases. As a result, sintered samples show higher coercivity as compared with annealed powder. However, the finely milled powder, ensuring better densification, turned out to be more prone to phase decomposition during sintering. The phase constitution of the samples was determined by X-ray diffraction, and magnetic hysteresis loops were recorded using a vibrating sample magnetometer. Scanning electron microscopy and electron backscatter diffraction were employed to study the microstructure and orientation distribution of grains after SPS. The dependence of coercivity and magnetization on the preparation conditions and sintering temperature is analyzed. To combine good magnetic properties with proper density, further optimization of the production parameters is necessary.
Autors: Muriel Tyrman;Simon Quetel-Weben;Alexandre Pasko;Loïc Perrière;Ivan Guillot;Victor Etgens;Frédéric Mazaleyrat;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» Fetal QT Interval Estimation Using Sequential Hypothesis Testing
Abstract:
Objective: Recent studies utilizing fetal magnetocardiography have demonstrated the efficacy of corrected QT interval (QTc) measurement for in utero diagnosis and prognosis of long QT syndrome, a leading cause of sudden death in early life. The objective of the study was to formulate and test a novel statistical estimation method to detect the end of the fetal T-wave and thereby improve the accuracy of fetal QT interval measurement. Methods: To detect the end of the T-wave, we apply a sequential composite hypothesis test to decide when the T-wave has returned to baseline. The method uses the generalized likelihood ratio test in conjunction with a low-rank spatiotemporal model that exploits the repetitive nature of cardiac signals. The unknown model parameters are determined using maximum likelihood estimation. Results: In realistic simulations, the detector was shown to be accurate to within 10 ms (95% prediction interval), even at noise-to-signal ratios as high as 6. When applied to real data from normal fetuses, the detector agreed well with measurements made by cardiologists ( 1.4 6.9 ms). Conclusions: The method was effective and practical. Detector performance was excellent despite the continual presence of strong maternal interference. Significance: This detector serves as a valuable adjunct to traditional measurement based on subjective assessment.
Autors: Suhong Yu;Barry D. Van Veen;William J. Lutter;Ronald T. Wakai;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Nov 2017, volume: 64, issue:11, pages: 2704 - 2710
Publisher: IEEE
 
» FFT-Based Method With Near-Matrix Compression
Abstract:
In this paper, a novel grouping scheme of the basis functions within the framework of the fast Fourier transform (FFT)-based method is proposed for creating a block-sparse structure for the near-matrix, and then FFT-based method with near-matrix compression is established for the efficient analysis of multiscale problems. For a multiscale problem, if an FFT-based method is required to maintain both higher efficiency and higher accuracy at calculating the far interactions, then the near-matrix will be inevitably very large. Compared with the traditional FFT-based method, the proposed method can significantly reduce the near-matrix memory requirement without increasing the time spent. Several numerical examples are provided to demonstrate the correctness and the efficiency of the proposed method.
Autors: Wei-Bin Kong;Hou-Xing Zhou;Kai-Lai Zheng;Xing Mu;Wei Hong;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5975 - 5983
Publisher: IEEE
 
» Field-Weakening Capability of Interior Permanent-Magnet Machines With Salient Pole Shoe Rotors
Abstract:
Brushless permanent-magnet (BLPM) machines, with inherent advantages of high-power density and high efficiency, have been widely employed to achieve traction characteristics for traction applications. Generally, traction characteristics require high torque at low speed and wide field-weakening region keeping constant power. However, both conventional interior permanent-magnet (IPM) and surface-mounted permanent-magnet (SPM) machines suffer from high-speed issues in the field-weakening region. A different BLPM machine topology, the pole shoe topology, is proposed in this paper. Although the pole shoe machine is common in industrial variable speed drives employing constant torque regimes, it has not been previously considered for machines designed for a wide field-weakening region. For analysis and comparison, a conventional IPM machine, which is employed as the Nissan Leaf vehicle traction machine, is studied as a reference benchmark machine. Experimental results from this machine are used to validate the analysis presented in this paper. The design results show that the proposed pole shoe machine achieves better field-weakening performance, compared with the conventional IPM and SPM machine topologies.
Autors: Nan Zhao;Nigel Schofield;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 7
Publisher: IEEE
 
» FineRoute: Personalized and Time-Aware Route Recommendation Based on Check-Ins
Abstract:
The rapid expansion of urbanization and the fast pace of life result in abundant choices with little time for people to manage routes. A proper planning route enables us to enjoy life better with fewer time and energy costs. Therefore, route planning becomes too valuable to be ignored. At the same time, with the popularity of mobile devices, location sensing, and Web 2.0 technologies, location-based social networks (e.g., Facebook Palaces and Foursquare) have attracted millions of users to share their visited locations and other information, which generates large amounts of user check-in data. These data can be used to mine users’ preferences and time information for recommending routes. In this paper, we propose FineRoute, a personalized and time-sensitive route recommendation system. We take three factors users’ preferences, proper visiting time, and transition time into consideration for the route generation. First, we infer users’ preferences by constructing a three-dimensional tensor, with three dimensions representing users, locations, and time, respectively. Second, we obtain the proper visiting time for certain locations, as well as the transition time between two locations from the check-in dataset. Moreover, we adopt Kullback–Leibler divergence in order to measure the quality of a route in terms of the proper visiting month and the proper visiting hour. Finally, we propose a route generation algorithm by extending the classic longest path algorithm. We conduct experiments on a real-world check-in dataset and the results demonstrate the effectiveness of our scheme.
Autors: Xiaoyan Zhu;Ripei Hao;Haotian Chi;Xiaojiang Du;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Nov 2017, volume: 66, issue:11, pages: 10461 - 10469
Publisher: IEEE
 
» FinTech: The New Frontier
Abstract:
This issue of IEEE Potentials focuses on the theme of financial technology (FinTech). Computers have played an increasing role in the field of finance for a long time. The development of automated teller machines and accounting software accounts for some of the early technological solutions that made the delivery of financial services easier, more convenient, and affordable. Significant investments have been made by banks and other financial service companies over the years to reach out to their customers, including individual and corporate clients.
Autors: Sharad Sinha;
Appeared in: IEEE Potentials
Publication date: Nov 2017, volume: 36, issue:6, pages: 6 - 7
Publisher: IEEE
 
» First Demonstration of AlSiO as Gate Dielectric in GaN FETs; Applied to a High Performance OG-FET
Abstract:
Gate dielectric plays an integral role in advancing the performance and reliability of GaN-based transistors. Si-alloying of aluminum oxide (Al2O3) dielectrics have been shown to provide a promising route to improve gate dielectric properties in GaN. In this letter, we report on the first demonstration of a GaN FET with aluminum silicon oxide (AlSiO) as the gate dielectric. Vertical normally-off GaN MOSFETs were fabricated on bulk GaN substrate. Excellent dc performance was achieved with a breakdown voltage of 1.2 kV, an ON-resistance of 2 .cm2, and a threshold voltage of 1.5 V (defined at /mm). A high breakdown electric-field of 2.3 MV/cm was calculated in these devices. In addition to vertical GaN MOSFET results, a comparative study of Al2O3 and AlSiO-based in situ GaN MOS capacitors, including time-dependent dielectric breakdown characteristics is also presented.
Autors: Chirag Gupta;Silvia H. Chan;Anchal Agarwal;Nirupam Hatui;Stacia Keller;Umesh K. Mishra;
Appeared in: IEEE Electron Device Letters
Publication date: Nov 2017, volume: 38, issue:11, pages: 1575 - 1578
Publisher: IEEE
 
» First Experimental Observation of Channel Thickness Scaling Induced Electron Mobility Enhancement in UTB-GeOI nMOSFETs
Abstract:
High quality ultrathin body (UTB)-Ge-on-insulator (GeOI) substrates have been fabricated with advanced layer transfer technology called HEtero-Layer-Lift-Off. With precise control of interfacial qualities, Ge crystallinity and thickness fluctuation in GeOI substrates, electron mobility of UTB-GeOI nMOSFETs with body thickness () from 20 to 3 nm has been systematically investigated. A significant electron mobility enhancement as scaling below 13 nm has been observed. This newly found mobility enhancement induced by channel thickness scaling could be attributed to the modulation of energy band structure in (001) confined UTB GeOI, where electron effective mass reduction is predicted by first-principle calculation.
Autors: Wen Hsin Chang;Toshifumi Irisawa;Hiroyuki Ishii;Hiroyuki Hattori;Hiroyuki Ota;Hideki Takagi;Yuichi Kurashima;Noriyuki Uchida;Tatsuro Maeda;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Nov 2017, volume: 64, issue:11, pages: 4615 - 4621
Publisher: IEEE
 
» First- Versus Second-Order Magnetocaloric Material for Thermomagnetic Energy Conversion
Abstract:
We estimate the power and efficiency of a thermal energy harvesting thermodynamic Brayton cycle using the first- and second-order magnetocaloric materials as active substance. The thermodynamic cycle was computed using a simple thermal exchange model and an equation of the state deduced from a phenomenological Landau model. For the first- and second-order materials, narrow- and high-frequency cycles are optimum and give similar performances. Considering technological issues hindering the increase of frequency, we introduced a more detailed approach, where we take into account the time needed to switch the material between two heat reservoirs. We show that the first-order material equation of the state leads thermodynamic cycle shape keeping it closer to the optimum cycle. Conditions to improve the performance of the second-order materials are discussed. In addition, we infer key remarks for prototype design regarding the power density and efficiency reachable in different configurations.
Autors: Morgan Almanza;Alexandre Pasko;Frédéric Mazaleyrat;Martino LoBue;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» First-Principles Study on the Magnetic Damping of Transition Metals in the Presence of Spin Fluctuation
Abstract:
We calculated, from first principles, the Landau frequency to investigate the effects of spin fluctuation on the magnetic damping of Fe and Ni metals as well as -type ordered alloys, namely, FePt, CoPt, FePd, and MnAl, assuming random arrangements of spins as an effect of thermal activation through coherent potential approximation and the tight-binding linear muffin-tin orbital method. The results show that the of these systems are similar to conductivity in the weak spin fluctuation region and resistivity in the strong fluctuation region as well as in the lattice vibration system. Qualitatively, this behavior is consistent with the experimental results for temperature dependence of the of Fe and Ni metals. For -type alloys, the magnitude of the magnetic damping is in the following (decreasing) order: CoPt, FePt, FePd, and MnAl.
Autors: Dai Ozaki;Daisuke Miura;Akimasa Sakuma;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» Fisher Vectors for PolSAR Image Classification
Abstract:
In this letter, we study the application of the Fisher vector (FV) to the problem of pixelwise supervised classification of polarimetric synthetic aperture radar images. This is a challenging problem since information in those images is encoded as complex-valued covariance matrices. We observe that the real parts of these matrices preserve the positive semidefiniteness property of their complex counterpart. Based on this observation, we derive an FV from a mixture of real Wishart densities and integrate it with a Potts-like energy model in order to capture spatial dependencies between neighboring regions. Experimental results on two challenging data sets show the effectiveness of the approach.
Autors: Javier Redolfi;Jorge Sánchez;Ana Georgina Flesia;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Nov 2017, volume: 14, issue:11, pages: 2057 - 2061
Publisher: IEEE
 
» Fixed-Time Synchronization of Complex Networks With Impulsive Effects via Nonchattering Control
Abstract:
Dealing with impulsive effects is one of the most challenging problems in the field of fixed-time control. In this paper, we solve this challenging problem by considering fixed-time synchronization of complex networks (CNs) with impulsive effects. By designing a new Lyapunov function and constructing comparison systems, a sufficient condition formulated by matrix inequalities is given to ensure that all the dynamical subsystems in the CNs are synchronized with an isolated system in a settling time, which is independent of the initial values of both the CNs and the isolated system. Then, by partitioning impulse interval and using the convex combination technique, sufficient conditions in terms of linear matrix inequalities are provided. Our synchronization criteria unify synchronizing and desynchronizing impulses. Compared with the existing controllers for fixed-time and finite-time techniques, the designed controller is continuous and does not include any sign function, and hence, the chattering phenomenon in most of the existing results is overcome. An optimal algorithm is proposed for the estimation of the settling time. Numerical examples are given to show the effectiveness of our new results.
Autors: Xinsong Yang;James Lam;Daniel W. C. Ho;Zhiguo Feng;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Nov 2017, volume: 62, issue:11, pages: 5511 - 5521
Publisher: IEEE
 
» Flame Detection on Swirl Burner Using ECT With Dynamic Reconstruction Algorithm Based on the Split Bregman Iteration
Abstract:
To achieve increased combustion efficiency and reduced pollutant generation, methods to describe the spatial distribution of combustion parameters, such as combustion intensity and temperature are desired. Electric capacitance tomography (ECT) is by nature sensitive to the electrical properties of a flame, facilitating combustion intensity imaging. In this paper, a novel image reconstruction algorithm is developed. It is based on an enhanced regularization methodology and adequate fusion of prior knowledge in the optimization of the objective functional through which a higher spatial resolution and lower errors of the reconstructed images are realized. Simulation results show very good agreement of the reconstructed images with typical phantoms. Also, a series of experiments are carried out for a range of flow rates of fuel and air. Data are collected by the ECT sensor and hardware, and the corresponding images are reconstructed by the new algorithm. The experiments demonstrate the advantages of the new method and ECT images correspond well with the variation of the combustion intensity. Further analysis agrees well with the established principle of combustion.
Autors: Jing Liu;Shi Liu;Wanting Zhou;Yiqun Kang;H. Inaki Schlaberg;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7290 - 7297
Publisher: IEEE
 
» Flexible AC Transmission Systems (FACTS) and Resilient AC Distribution Systems (RACDS) in Smart Grid
Abstract:
Transmission and distribution (T&D) networks are a critical part of the power grid. As moving towards a smart-grid, it is essential to modernize the T&D networks and make it “Smart-grid ready”. The concept of flexible ac transmission systems (FACTS) has been well-known for three decades. Rapid advancements in power electronics technology in the past decades have led to a new generation of FACTS devices. The Modern FACTS technology helps the transition of transmission networks to “smart”. With increasing penetration of distributed generation, the distribution network is seeing unprecedented variation in terms of its fundamental operation and control, from renewable energy integration to microgrid, from active control of power quality, volt/var and frequency to self-healing and islanding operation. As a key part of smart-grid at the distribution level, we summarize the current efforts as a concept of resilient ac distribution systems (RACDS). The concepts of both FACTS and RACDS for a smart grid are introduced in this paper. Different configurations, key benefits, operating principles and world-wide installations of FACTS and RACDS devices are presented in detail. The ongoing and future direction of R&D leading to newer generations of FACTS and RACDS are also discussed.
Autors: Fang Z. Peng;
Appeared in: Proceedings of the IEEE
Publication date: Nov 2017, volume: 105, issue:11, pages: 2099 - 2115
Publisher: IEEE
 
» Flexible Organic Single-Crystal Field-Effect Transistor for Ultra-Sensitivity Strain Sensing
Abstract:
To date, the functional application of the flexible organic single-crystal devices in strain sensors has not been studied. In this letter, the excellent flexibility of the beltlike rubrene single crystals enables the rubrene single-crystal field-effect transistors to be bent inward and outward, and their electrical properties under compressive and tensile strain are demonstrated. The current and mobility of the device show the nearly linear changes under the tensile and compressive strain of <0.4%. The dynamic response of the strain presents good repeatability. The calculated sensitivity under tensile strain is two orders of magnitude higher than the previously reported organic thin-film-based strain sensor. It is demonstrated that the rubrene single-crystal device can effectively detect the movement of a human finger. These results exhibit the promising potential of our transistors in artificial intelligence and healthcare systems.
Autors: Haiting Wang;Liangliang Deng;Qingxin Tang;Yanhong Tong;Yichun Liu;
Appeared in: IEEE Electron Device Letters
Publication date: Nov 2017, volume: 38, issue:11, pages: 1598 - 1601
Publisher: IEEE
 
» FLiER: Practical Topology Update Detection Using Sparse PMUs
Abstract:
In this paper, we present a Fingerprint Linear Estimation Routine to identify topology changes in power networks using readings from sparsely deployed phasor measurement units (PMUs). When a power line, load, or generator trips in a network, or when a substation is reconfigured, the event leaves a unique “voltage fingerprint” of bus voltage changes that we can identify using only the portion of the network directly observed by the PMUs. The naive brute-force approach to identify a failed line from such voltage fingerprints, though simple and accurate, is slow. We derive an approximate algorithm based on a local linearization and a novel filtering approach that is faster and only slightly less accurate. We present experimental results by using the IEEE 57-bus, IEEE 118-bus, and Polish 1999-2000 winter peak networks.
Autors: Colin Ponce;David S. Bindel;
Appeared in: IEEE Transactions on Power Systems
Publication date: Nov 2017, volume: 32, issue:6, pages: 4222 - 4232
Publisher: IEEE
 
» Flux Weakening Performance of Permanent Magnet Synchronous Motor With a Conical Rotor
Abstract:
The general flux weakening control method for permanent magnet synchronous motor (PMSM) is changing the angle between the current and the no-load back-electromotive force (EMF). This paper presents a novel structure of PMSM with a conical rotor (CR-PMSM) and studies its flux weakening performance in detail. The CR can be moved outside in axial direction, which decreases the air-gap flux density as well as the effective space between the stator and the rotor. This method is effective in increasing the maximum speed and the output power of PMSM, including the surface-type and interior-type. 3-D finite-element model is used to simulate the magnetic-field distribution, flux weakening, and driving performance in CR-PMSM according to rotor axial displacement. The motoring performance of CR-PMSM is compared with that of the general method. A prototype machine with a cone angle of 5.7 and a rated power of 140 W at a rated speed of 300 rpm is designed and built to validate the theory.
Autors: Feng Chai;Kui Zhao;Zongyang Li;Lei Gan;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 6
Publisher: IEEE
 
» Fog-Based Evaluation Approach for Trustworthy Communication in Sensor-Cloud System
Abstract:
A sensor-cloud system is a combination of wireless sensor networks and cloud computing that is equipped with ubiquitous physical sensing ability, high-speed computation, huge storage, and so on. However, sensor-cloud systems suffer from various types of malicious attacks that can cause sensor communications to become unreliable. Establishing a trust evaluation method to ensure members’ reliability in sensor cloud is an effective way to resist malicious attacks. However, most current trust evaluation methods are constrained to specific attacks or applications, and they lack compatibility, verifiability, and scalability. To solve these problems, we formulated the trust evaluation issue as a multiple linear regression problem. Considering energy restrictions, we adopt fog nodes to assist in the trust computation. Moreover, the least squares algorithm is used to find the fitting function between the communication feature and the trust value. The experimental results show that our approach can find the best trust evaluation model and improve the compatibility, verifiability, and accuracy of trust evaluation.
Autors: Tian Wang;Yang Li;Yonghong Chen;Hui Tian;Yiqiao Cai;Weijia Jia;Baowei Wang;
Appeared in: IEEE Communications Letters
Publication date: Nov 2017, volume: 21, issue:11, pages: 2532 - 2535
Publisher: IEEE
 
» Force Characteristic Analysis of a Linear Magnetic Bearing With Rhombus Magnet Array for Magnetic Levitation Positioning System
Abstract:
Magnetic levitation positioning systems (MLPSs) are of great interest in high-precision applications in vacuum. In this paper, a linear magnetic bearing with rhombus magnet array (RMA-LMB) for MLPS is proposed. With the RMA, the proposed RMA-LMB possesses advantages of excellent force uniformity, high force density, and good manufacturability. First, the basic structure and operating principle of the proposed RMA-LMB are presented. Second, the expressions of magnetic field, static force and torque, and dynamic force and torque are obtained by an equivalent current model. Third, the 3-D finite-element analysis (3-D FEA) is employed to investigate the RMA-LMB, and the magnetic field distribution, the static force and torque, as well as the dynamic force and torque are analyzed. Finally, a prototype is constructed, and experiments show a good agreement with the FEA results.
Autors: Yiheng Zhou;Baoquan Kou;He Zhang;Jun Luo;Lei Gan;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 7
Publisher: IEEE
 
» Forensic Identification of Anonymous Sources in OneSwarm
Abstract:
OneSwarm is a p2p system for anonymous file sharing. We quantify the system’s vulnerability to three attacks that identify the sources of files. First, we detail and prove that a timing attack allows a single attacker to investigate all its neighbors for possession of specific files. We prove the attack is possible due to OneSwarm’s design and is unthwarted by changes made to OneSwarm since we released our attack. Second, we show that OneSwarm is much more vulnerable to a collusion attack than previously reported, and we quantify the attack’s success given a file’s popularity, a factor not evaluated earlier. Third, we present a novel application of a known TCP-based attack. It allows a single attacker to identify whether a neighbor is the source of data or a proxy for it. Each of these attacks can be repeated as attackers quit and rejoin the network. We present these attacks in the context of forensics and the investigation of child pornography. We show that our attacks meet the higher standards required of law enforcement for criminal investigations.
Autors: George Bissias;Brian Neil Levine;Marc Liberatore;Swagatika Prusty;
Appeared in: IEEE Transactions on Dependable and Secure Computing
Publication date: Nov 2017, volume: 14, issue:6, pages: 620 - 632
Publisher: IEEE
 
» Foreword to the Special Issue on Modeling and Simulation of Remote Sensing Data
Abstract:
The papers in this special issue focus on the deployment modeling and simulation in remote sensing applications which play important roles in the development and application of remote sensing technology. While modeling occurs in many aspects of remote sensing including in the representation of natural phenomena and in the development and use of data analysis algorithms, a particular role of models is in the creation of the signatures and signals that lead to the remotely sensed measurements from which we can extract information about the scene.
Autors: J. P. Kerekes;J. Shi;L. Tsang;J.-P. Gastellu-Etchegorry;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Nov 2017, volume: 10, issue:11, pages: 4663 - 4665
Publisher: IEEE
 
» Formation of $L1_{0}$ -FePt(001) Ultra-Thin Films With Flat Surfaces Using VC and VN Underlayers
Abstract:
FePt alloy films of 2 to 10 nm thicknesses are prepared on (001) single-crystal underlayers of MgO, VN, and VC by employing a two-step method consisting of low-temperature deposition at 200 °C followed by high-temperature annealing at 600 °C. MgO, VN, and VC crystals are selected as underlayer materials, since the crystals have the same NaCl-type crystal structure and similar lattice constants of about 0.42 nm but different surface energies. The single-crystal underlayers are prepared by RF sputtering on the single-crystal substrates of MgO and SrTiO3 at 600 °C. The influences of underlayer material and FePt film thickness on the ordering degree, the magnetic properties, and the surface morphology are systematically investigated. Epitaxial films involving (001) crystal structure with the -axis normal to the substrate surface are formed on all the underlayers. As the film thickness decreases, the ratio of out-of-plane to in-plane lattice constant decreases and the ordering degree increases. Stronger perpendicular magnetic anisotropy is observed for an FePt film with a higher value. The film thickness trends of , , and magnetic properties are similar to those for FePt films thicker than 5 nm formed on MgO underlayers. However, when the thickness is decreased to 2 nm, de-wetting of depos- ted atoms occurs on MgO underlayers during annealing at 600 °C. The surfaces of 2-nm-thick films formed on MgO underlayers are composed of isolated islands. On the contrary, continuous surfaces are realized for the investigated film thickness range of 2–10 nm in the cases of VC and VN underlayers. The surface roughness of FePt film formed on VN underlayer (: 0.1–0.2 nm) is lower than that of film formed on VC underlayer (: 0.1–0.4 nm). This paper shows that the employment of a VN underlayer is effective in the preparation of ordered FePt ultra-thin film with flat surface.
Autors: Tomoki Shimizu;Mitsuru Ohtake;Masaaki Futamoto;Fumiyoshi Kirino;Nobuyuki Inaba;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» Four-State Full Q-Band Phase Shifter Using Smooth-Ridged Waveguides
Abstract:
A novel four-state full Q-band waveguide phase shifter based on smooth-ridged sections is presented. The waveguide structure combines differential 90° and 180° phase shifters, whose combination provides the four-phase states (0°, 90°, 180°, and 270°) by appropriately controlling a set of millimeter-wave switches. Each differential phase shifter is performed using an E-plane continuous profile ridge to reach the 90° or 180° phase shift, respectively. The phase shifter module provides outstanding performance covering the full Q-band (33–50 GHz) with average phase results of 93.5°, 182.8°, and 270.6°.
Autors: Enrique Villa;Beatriz Aja;Jaime Cagigas;Eduardo Artal;Luisa de la Fuente;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Nov 2017, volume: 27, issue:11, pages: 995 - 997
Publisher: IEEE
 
» Fractional Spectral Analysis of Randomly Sampled Signals and Applications
Abstract:
Nonuniform sampling can be utilized to achieve certain desirable results. Periodic nonuniform sampling can decrease the required sampling rate for signals. Random sampling can be used as a digital alias-free signal processing method in analog-to-digital conversion. In this paper, we first present the fractional spectrum estimation of signals that are bandlimited in the fractional Fourier domain based on the general periodic random sampling approach. To show the estimation effect, the unbiasedness, the variance, and the optimal estimation condition are analyzed. The reconstruction of the fractional spectrum from the periodic random samples is also proposed. Second, the effects of sampling jitters and observation errors on the performance of the fractional spectrum estimation are analyzed, where the new defined fractional characteristic function is used to compensate the estimation bias from sampling jitters. Furthermore, we investigate the fractional spectral analysis from two widely used random sampling schemes, i.e., simple random sampling and stratified random sampling. Finally, all of the analysis results are applied and verified using a radar signal processing system.
Autors: Liyun Xu;Feng Zhang;Ran Tao;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Nov 2017, volume: 66, issue:11, pages: 2869 - 2881
Publisher: IEEE
 
» Frame Aggregation in Central Controlled 802.11 WLANs: The Latency Versus Throughput Tradeoff
Abstract:
Frame aggregation is widely used in 802.11 WLANs in order to provide a significant throughput improvement. However, the latency increase that comes as a counterpart can reduce the quality experienced by the users of applications with real-time constraints. This letter explores the throughput versus latency tradeoff in the context of central controlled solutions (e.g. SDWN-based). First, a scenario with a single Access Point (AP) is used to illustrate the problem and to propose two possible solutions. Then, a centralized algorithm that dynamically (de)activates aggregation is tested in a scenario with a number of APs. The results show that aggregation parameters can be tuned in order to keep latency in low levels, with a low throughput penalty.
Autors: Jose Saldana;José Ruiz-Mas;José Almodóvar;
Appeared in: IEEE Communications Letters
Publication date: Nov 2017, volume: 21, issue:11, pages: 2500 - 2503
Publisher: IEEE
 
» Free-Space Optical Communication Impaired by Angular Fluctuations
Abstract:
In this paper, the impairments of free-space optical (FSO) communication systems caused by angular fluctuations including beam misalignment and angle-of-arrival (AOA) fluctuations are modeled in the presence of both atmospheric turbulence and transceiver vibrations. In particular, assuming FSO receivers with a limited field-of-view (FOV), the fading caused by AOA fluctuations is studied. The outage probability expressions for both coherent and direct detections are derived in both shot-noise-limited and thermal-noise-limited regimes. For direct detection, the optimal receiver FOV that achieves the minimum outage probability is considered. Furthermore, the issue of imperfect phasefront tracking in practical coherent receivers is investigated.
Autors: Shenjie Huang;Majid Safari;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Nov 2017, volume: 16, issue:11, pages: 7475 - 7487
Publisher: IEEE
 
» Freezing of Gait Detection in Parkinson's Disease: A Subject-Independent Detector Using Anomaly Scores
Abstract:
Freezing of gait (FoG) is common in Parkinsonian gait and strongly relates to falls. Current clinical FoG assessments are patients’ self-report diaries and experts’ manual video analysis. Both are subjective and yield moderate reliability. Existing detection algorithms have been predominantly designed in subject-dependent settings. In this paper, we aim to develop an automated FoG detector for subject independent. After extracting highly relevant features, we apply anomaly detection techniques to detect FoG events. Specifically, feature selection is performed using correlation and clusterability metrics. From a list of 244 feature candidates, 36 candidates were selected using saliency and robustness criteria. We develop an anomaly score detector with adaptive thresholding to identify FoG events. Then, using accuracy metrics, we reduce the feature list to seven candidates. Our novel multichannel freezing index was the most selective across all window sizes, achieving sensitivity (specificity) of (). On the other hand, freezing index from the vertical axis was the best choice for a single input, achieving sensitivity (specificity) of () for ankle and () for back sensors. Our subject-independent method is not only significantly more accurate than those previously reported, but also uses a much smaller window (e.g., versus $ text{7.5},text{s}$ ) and/or lower tolerance (e.g., versus ).
Autors: Thuy T. Pham;Steven T. Moore;Simon John Geoffrey Lewis;Diep N. Nguyen;Eryk Dutkiewicz;Andrew J. Fuglevand;Alistair L. McEwan;Philip H.W. Leong;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Nov 2017, volume: 64, issue:11, pages: 2719 - 2728
Publisher: IEEE
 
» Frequency-Efficient Receding Horizon $H_infty $ FIR Filtering in Discrete-Time State-Space
Abstract:
We solve a robust receding horizon finite impulse response (FIR) filtering problem in a discrete-time state space in three frequency regions under severe disturbances. Novel design conditions are derived for the finite frequency region FIR filter, called FFFF or 4F, in terms of the linear matrix inequality and equality constraint, such that the 4F ensures the performance and deadbeat property. The 4F attenuates the effects of disturbances in the user-given low-, middle-, and high-frequency regions. The new design conditions, which do not involve the equality constraint, are also investigated. An example of applications for the -404 turbofan engine system demonstrates the much better performance of the proposed 4F compared with the existing entire frequency FIR filter and the finite frequency region infinite impulse response filter.
Autors: Choon Ki Ahn;Shunyi Zhao;Yuriy S. Shmaliy;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Nov 2017, volume: 64, issue:11, pages: 2945 - 2953
Publisher: IEEE
 
» Frequency-Tunable Tri-Function Filter
Abstract:
In this paper, we present a reconfigurable filter capable of having three different responses, such as bandstop, bandpass, and all-pass responses. For designing the tri-function filter, we have developed a new topology containing coupled resonators and a switch-embedded transmission line running from the input to output ports. A bandpass response can be obtained by opening the switches embedded in the transmission line. On the other hand, closing the switches produces bandstop and all-pass responses. The details of the coupling structure design satisfying three sets of the coupling coefficients for the three responses are presented. In addition, we also discuss in detail an approach for incorporating the measured parameters of the nonideal switch in our filter design. For demonstration, a frequency-tunable tri-function filter has been designed using substrate-integrated waveguide resonators. It is shown that the designed filter is able to exhibit three responses over a 1.2:1 frequency tuning range.
Autors: Tae-Hak Lee;Boyoung Lee;Seunggoo Nam;Young-Sik Kim;Juseop Lee;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Nov 2017, volume: 65, issue:11, pages: 4584 - 4592
Publisher: IEEE
 
» Frequency-Tuning Method Using the Reflection Coefficient in a Wireless Power Transfer System
Abstract:
In this letter, we compare two operating frequency tuning methods—the zero phase angle (ZPA) and the minimum reflection coefficient magnitude (MRCM) frequency tuning methods—to enhance the power transfer efficiency and output power in the wireless power transfer (WPT) system. For the MRCM frequency tuning method which has been introduced recently, the WPT system can be analyzed by considering the system as a matching network connected to a generator and a load. Through experiments, in the over-coupled region, the MRCM frequency tuning method has higher output power and efficiency than the ZPA frequency tuning method. Above all, the MRCM frequency tuning method does not need the information on the coupling coefficient as well as the primary and secondary resonators.
Autors: Dong-Wook Seo;Jae-Ho Lee;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Nov 2017, volume: 27, issue:11, pages: 959 - 961
Publisher: IEEE
 
» Fresnel Lens at Millimeter-Wave: Enhancement of Efficiency and Radiation Frequency Bandwidth
Abstract:
In this paper, the performance of Fresnel lens antennas is investigated in detail. The performance is evaluated in terms of aperture efficiency and stable radiation pattern over a wide frequency band. This paper proposes an efficient technique for enhancing aperture efficiency by smoothly compensating for the spherical phase front arriving upon the lens surface. The feeder has been optimized to fit an axially symmetric cosn-like radiation pattern. For this, an accurate technological process has been used to manufacture a lens that allows for smooth compensation of the phase shift. The lens is compared with a classic Fresnel lens having the same physical dimensions and feeding system. The improvement is validated by measurement, which has revealed a maximum measured gain of 38.9 dBi corresponding to a maximum measured aperture efficiency of 59% with a −2 dB radiation frequency bandwidth of 29.25 GHz around 90 GHz. This amounts to an aperture efficiency enhancement of 60% and −2 dB radiation frequency bandwidth enhancement of 72% as compared with those of the classic Fresnel lens.
Autors: Antoine Jouade;Mohamed Himdi;Olivier Lafond;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5776 - 5786
Publisher: IEEE
 
» Friction Characteristics of Ultrathin Perfluoropolyether Boundary Lubricant Films Subjected to Laser Irradiation Heating in Heat-Assisted Magnetic Recording
Abstract:
We investigated the laser-heating-temperature dependence of the friction characteristics of magnetic disks coated with boundary lubricant films by using a pin-on-disk tester and discussed the fundamental characteristics observed. In the contact area of the glass pin and disk, we observed the area that showed a buildup and depletion of the lubricant film thickness. The amount of buildup and depletion increased with increasing heating temperature. It was found that the friction coefficient of each lubricant film initially decreased as the temperature increased. Thereafter, the minimum value of the friction coefficient of each test lubricant occurred at a specific temperature, resulting in an increase in the friction coefficient inversely as the temperature further increased. It was suggested that the specific temperature corresponds to the transition temperature at which the test lubricant film evaporates. In addition, it was also suggested that the thermal durability of the lubricant film improved because of ultraviolet treatment.
Autors: Norio Tagawa;Hiroshi Tani;Shinji Koganezawa;Renguo Lu;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» From Log-Determinant Inequalities to Gaussian Entanglement via Recoverability Theory
Abstract:
Many determinantal inequalities for positive definite block matrices are consequences of general entropy inequalities, specialized to Gaussian distributed vectors with prescribed covariances. In particular, strong subadditivity (SSA) yields for all block matrices , where subscripts identify principal submatrices. We shall refer to the above-mentioned inequality as SSA of log-det entropy. In this paper, we develop further insights on the properties of the above-mentioned inequality and its applications to classical and quantum information theory. In the first part of this paper, we show how to find known and new necessary and sufficient conditions under which saturation with equality occurs. Subsequently, we discuss the role of the classical transpose channel (also known as Petz recovery map) in this problem and find its action explicitly. We then prove some extensions of the saturation theorem, by finding faithful lower bounds on a log-det conditional mutual information. In the second part, we focus on quantum Gaussian states, whose covariance matrices are not only positive but obey additional constraints due to the uncertainty relation. For Gaussian states, the log-det entropy is equivalent to the Rényi entropy of order 2. We provide a strengthening of log-det SSA for quantum covariance matrices that involves the so-called Gaussian Rényi-2 entanglement of formation, a well-behaved entanglement measure defined via a Gaussian convex roof construction. We then employ this result to define a log-det entropy equivalent of the squashed entanglement measure, which is remarkably shown to coincide with the Gaussian R- ;nyi-2 entanglement of formation. This allows us to establish useful properties of such measure(s), such as monogamy, faithfulness, and additivity on Gaussian states.
Autors: Ludovico Lami;Christoph Hirche;Gerardo Adesso;Andreas Winter;
Appeared in: IEEE Transactions on Information Theory
Publication date: Nov 2017, volume: 63, issue:11, pages: 7553 - 7568
Publisher: IEEE
 
» From the editors' desk
Abstract:
Presents the introductory editorial for this issue of the publication.
Autors: Ed Cherney;Robert Fleming;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Nov 2017, volume: 33, issue:6, pages: 6 - 7
Publisher: IEEE
 
» Fuel Cell Power Systems and Applications
Abstract:
Fuel cell power systems offer a unique combination of high efficiency, wide size range, modularity, and compatibility with cogeneration. The development of complete energy systems that realize the benefits offered by fuel cell technology requires a basic understanding of fuel cell system components as well as the associated power electronics for different applications. This paper explains the basic characteristics of a fuel cell system, describes the different types of fuel cells and their current state of development, and discusses the potential application of these systems to transportation and stationary power. Particular emphasis is given to the electrical characteristics of the fuel cell, which is a relatively stiff power source. Power electronic systems are essential for making the fuel cell electrical output compatible with most loads. Options for dc–dc and dc–ac power conversion circuits are given with a discussion of the distinct features of each circuit that can be used for system planning purposes. The interaction between a fuel cell and a single-phase ac inverter load is highlighted because of the widespread applicability of this particular combination.
Autors: Jih-Sheng Lai;Michael W. Ellis;
Appeared in: Proceedings of the IEEE
Publication date: Nov 2017, volume: 105, issue:11, pages: 2166 - 2190
Publisher: IEEE
 
» Full Charge Capacity and Charging Diagnosis of Smartphone Batteries
Abstract:
Full charge capacity (FCC) refers to the amount of charge a battery can hold. It is the fundamental property of smartphone batteries that diminishes as the battery ages and is charged/discharged. We investigate the behavior of smartphone batteries while charging and demonstrate that battery voltage and charging rate information can together characterize the FCC of a battery. We propose a new method for accurately estimating FCC without exposing low-level system details or introducing new hardware or system modules. We further propose and implement a collaborative FCC estimation technique that builds on crowd-sourced battery data. The method finds the reference voltage curve and charging rate of a particular smartphone model from the data and then compares with those of an individual device. After analyzing a large data set towards a crowd-sourced rate versus FCC model, we report that 55 percent of all devices and at least one device in 330 out of 357 unique device models lost some of their FCC. For some old device models, the median capacity loss exceeded 20 percent. The models further enable debugging the performance of smartphone charging. We propose an algorithm, called BatterySense, which utilizes crowd-sourced rate to detect abnormal charging performance, estimate FCC of the device battery, and detect battery changes.
Autors: Mohammad Ashraful Hoque;Matti Siekkinen;Jonghoe Koo;Sasu Tarkoma;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Nov 2017, volume: 16, issue:11, pages: 3042 - 3055
Publisher: IEEE
 
» Full-Body Animation of Human Locomotion in Reduced Gravity Using Physics-Based Control
Abstract:
The proposed physics-based approach can generate stable and robust full-body animation of various gaits under different gravitational conditions. As input, this method takes motion-captured human motions in the Earth’s gravity and builds an inverted-pendulum on cart (IPC) control model, which is analyzed using the motion-captured data. The authors use a pre-estimation model based on the Froude number to predict the desired velocity and stride frequency of a character model in hypogravity and then generate full-body animation using a pendulum trajectory generator, motion planner, and tracking.
Autors: Yun-hyeong Kim;Taesoo Kwon;Daeun Song;Young J. Kim;
Appeared in: IEEE Computer Graphics and Applications
Publication date: Nov 2017, volume: 37, issue:6, pages: 28 - 39
Publisher: IEEE
 
» Fully Nonlinear ${SP}_{3}$ Approximation Based Fluorescence Optical Tomography
Abstract:
In fluorescence optical tomography, many works in the literature focus on the linear reconstruction problem to obtain the fluorescent yield or the linearized reconstruction problem to obtain the absorption coefficient. The nonlinear reconstruction problem, to reconstruct the fluorophore absorption coefficient, is of interest in imaging studies as it presents the possibility of better reconstructions owing to a more appropriate model. Accurate and computationally efficient forward models are also critical in the reconstruction process. The approximation to the radiative transfer equation (RTE) is gaining importance for tomographic reconstructions owing to its computational advantages over the full RTE while being more accurate and applicable than the commonly used diffusion approximation. This paper presents Gauss–Newton-based fully nonlinear reconstruction for the approximated fluorescence optical tomography problem with respect to shape as well as the conventional finite-element method-based representations. The contribution of this paper is the Frechet derivative calculations for this problem and demonstration of reconstructions in both representations. For the shape reconstructions, radial-basis-function represented level-set-based shape representations are used. We present reconstructions for tumor-mimicking test objects in scattering and absorption dominant settings, respectively, for moderately noisy data sets in order to demonstrate the viability of the formulation. Comparisons are presented between the nonlinear and linearized reconstruction schemes in an element wise setting to illustrate the benefits of using the former especially for absorption dominant media.
Autors: Naren Naik;Nishigandha Patil;Yamini Yadav;Jerry Eriksson;Asima Pradhan;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Nov 2017, volume: 36, issue:11, pages: 2308 - 2318
Publisher: IEEE
 
» Fully Relativistic Temperature-Dependent Electronic Transport Properties of Magnetic Alloys From the First Principles
Abstract:
Ab initio calculations based on the fully relativistic Dirac approach and incorporating chemical disorder and temperature-induced atomic displacements (phonons) are presented. The tight-binding linear muffin-tin orbital method is used, and the multicomponent coherent potential approximation deals with the chemical disorder and phonons on the same level. Electrical resistivities calculated without and with spin–orbit interaction are compared, and the anomalous Hall effect for magnetic alloys is investigated. The developed technique is tested on pure nickel and on random binary Cu–Ni alloys. The calculated results are found to be in good agreement with experimental and other theoretical data. The combined effect of phonons and spin disorder, simulated within the disordered local moment state, has also been studied. The results confirm the validity of Matthiessen’s rule in a wide range of temperatures for the electrical resistivity of pure nickel.
Autors: David Wagenknecht;Karel Carva;Ilja Turek;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» Functionalization of Iron Oxide Nanoparticles With HSA Protein for Thermal Therapy
Abstract:
Over the past two decades, important progress has been made in the development of nanomaterials, especially for biomedical applications. The surface of magnetic nanoparticles (MNPs) can be modified and functionalized with a targeting agent in order to improve their longevity in the blood, their cell internalization, and their efficiency. However, after this functionalization, some of their physical properties may be modified. In this paper, spinel iron-oxide single crystals 10 nm in diameter were elaborated and functionalized with human serum albumin (HSA) protein, to give an MNP–HSA nano-platform. Physicochemical studies were performed to evaluate this nano-platform utility in nanomedicine. X-ray photoelectron spectroscopy and thermogravimetry were used to establish the presence of protein at the surface of MNP. MNP–HSA shows very good colloidal stability with a zeta potential of −35.4 ±0.6 mV at physiological pH (7.4). MNP–HSA is superparamagnetic and exhibits a saturation magnetization (Ms) of 63 emu.g−1 at 310 K and produces localized heat in an alternating magnetic field; the specific absorption rate (SAR) of an aqueous suspension of MNP–HSA is 123 W.g−1. To identify the relative contributions of Brownian and Néel relaxations in its heating process, MNP–HSA was immobilized in an agarose gel, where the SAR was found to be the same as in water. This indicates that Néel relaxation is the dominant nanoheating mechanism.
Autors: E. Mazario;A. Forget;H. Belkahla;J. S. Lomas;P. Decorse;A. Chevillot-Biraud;P. Verbeke;C. Wilhelm;S. Ammar;J-M. El Hage Chahine;M. Hemadi;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» Functionalization of Magnetic Hollow Spheres With (3-Aminopropyl)Triethoxysilane for Controlled Drug Release
Abstract:
Direct functionalization strategy has been employed to modify the surface of the magnetic hollow spheres (MHS) with (3-aminopropyl)triethoxysilane (APTES) for controlled drug release. The MHS were prepared by the solvothermal method and characterized by X-ray diffraction, field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy, and vibrating sample magnetometer. The FE-SEM study shows that MHS have a size of ~200 nm and are made up of smaller nanoparticles (NPs) having average size of ~20–25 nm. MHS exhibits a superparamagnetic behavior with a saturation magnetization of 74 emu/g at room temperature. The direct functionalization of MHS with APTES provided an efficient loading of model anti-cancer drug Camptothecin (CPT). The drug release study performed at pH of 7.4 showed 30% of CPT release in a controlled way after 4 h.
Autors: P. B. Patil;V. C. Karade;P. P. Waifalkar;Subasa C. Sahoo;P. Kollu;M. S. Nimbalkar;A. D. Chougale;P. S. Patil;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» Fundamental Tradeoff Between Storage and Latency in Cache-Aided Wireless Interference Networks
Abstract:
This paper studies the fundamental tradeoff between storage and latency in a general wireless interference network with caches equipped at all transmitters and receivers. The tradeoff is characterized by an information-theoretic metric, normalized delivery time (NDT), which is the worst case delivery time of the actual traffic load at a transmission rate specified by degrees of freedom of a given channel. We obtain both an achievable upper bound and a theoretical lower bound of the minimum NDT for any number of transmitters, any number of receivers, and any feasible cache size tuple. We show that the achievable NDT is exactly optimal in certain cache size regions, and is within a bounded multiplicative gap to the theoretical lower bound in other regions. In the achievability analysis, we first propose a novel cooperative transmitter/receiver coded caching strategy. It offers the freedom to adjust file splitting ratios for NDT minimization. We then propose a delivery strategy that transforms the considered interference network into a new class of cooperative X-multicast channels. It leverages local caching gain, coded multicasting gain, and transmitter cooperation gain (via interference alignment and interference neutralization) opportunistically. Finally, the achievable NDT is obtained by solving a linear programming problem. This paper reveals that with caching at both transmitter and receiver sides, the network can benefit simultaneously from traffic load reduction and transmission rate enhancement, thereby effectively reducing the content delivery latency.
Autors: Fan Xu;Meixia Tao;Kangqi Liu;
Appeared in: IEEE Transactions on Information Theory
Publication date: Nov 2017, volume: 63, issue:11, pages: 7464 - 7491
Publisher: IEEE
 
» Fusing Microwave and Optical Satellite Observations to Simultaneously Retrieve Surface Soil Moisture, Vegetation Water Content, and Surface Soil Roughness
Abstract:
Uncertainty in surface soil roughness strongly degrades the performance of surface soil moisture (SSM) and vegetation water content (VWC) retrieval from passive microwave observations. This paper proposes an algorithm to objectively determine the surface soil roughness parameter of the radiative transfer model by fusing microwave and optical satellite observations. It is then demonstrated in a semiarid in situ observation site. The roughness correction of this new algorithm positively impacted the performance of SSM (root-mean-square error reduced from 0.088 to 0.070) and VWC retrieval from the Advanced Microwave Scanning Radiometer 2 and Moderate Resolution Imaging Spectroradiometer. Since this surface soil roughness correction may be transferrable to other microwave satellite retrieval algorithms such as those for the Soil Moisture and Ocean Salinity and Soil Moisture Active Passive satellites, this new algorithm can contribute to many microwave earth surface observation satellite missions.
Autors: Yohei Sawada;Toshio Koike;Kentaro Aida;Kinya Toride;Jeffrey P. Walker;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Nov 2017, volume: 55, issue:11, pages: 6195 - 6206
Publisher: IEEE
 
» Fusion of Hyperspectral and LiDAR Data Using Sparse and Low-Rank Component Analysis
Abstract:
The availability of diverse data captured over the same region makes it possible to develop multisensor data fusion techniques to further improve the discrimination ability of classifiers. In this paper, a new sparse and low-rank technique is proposed for the fusion of hyperspectral and light detection and ranging (LiDAR)-derived features. The proposed fusion technique consists of two main steps. First, extinction profiles are used to extract spatial and elevation information from hyperspectral and LiDAR data, respectively. Then, the sparse and low-rank technique is utilized to estimate the low-rank fused features from the extracted ones that are eventually used to produce a final classification map. The proposed approach is evaluated over an urban data set captured over Houston, USA, and a rural one captured over Trento, Italy. Experimental results confirm that the proposed fusion technique outperforms the other techniques used in the experiments based on the classification accuracies obtained by random forest and support vector machine classifiers. Moreover, the proposed approach can effectively classify joint LiDAR and hyperspectral data in an ill-posed situation when only a limited number of training samples are available.
Autors: Behnood Rasti;Pedram Ghamisi;Javier Plaza;Antonio Plaza;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Nov 2017, volume: 55, issue:11, pages: 6354 - 6365
Publisher: IEEE
 
» G2RHA:Group-to-Route Handover Authentication Scheme for Mobile Relays in LTE-A High-Speed Rail Networks
Abstract:
The introduction of mobile relay node (MRN) in long-term evolution advanced high-speed rail networks is an attractive method to provide uninterrupted connectivity for the group of user equipments on board. However, MRNs still suffer from frequent handovers and several security threats due to several rounds of message exchange and the insecure air interface between MRNs and donor eNBs (DeNBs). In this paper, we propose a group-to-route handover authentication scheme based on trajectory prediction for mobile relays. By our scheme, all of the DeNBs deployed along the trajectory can be formed a route-DeNB group and all of the MRNs deployed in the same train can construct a MRN group. Compared with the current 3GPP standards and other related schemes, our scheme can accomplish the mutual authentication and key agreement between the MRN group and the target DeNB with ideal efficiency in terms of authentication signaling overhead, bandwidth consumption, and computational cost. Security analysis by using the BAN logic and formal verification tool Scyther show that our scheme can work correctly and withstand several protocol attacks.
Autors: Jin Cao;Maode Ma;Hui Li;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Nov 2017, volume: 66, issue:11, pages: 9689 - 9701
Publisher: IEEE
 
» Gain-Enhanced Patch Antenna Without Enlarged Size via Loading of Slot and Shorting Pins
Abstract:
A patch antenna with loading of slot and shorting pins is proposed in this paper to enhance the radiation gain without increasing the patch size. At first, a straight slot is transversely introduced in the central line of a patch. For the dominant TM01 mode, this central line behaves as a virtual electric wall with zero electric field and maximum surface current underneath and on the patch, respectively. By doing so, the central slot serves as an extra radiator so that this slot-loaded patch produces radiation as an equivalent three-slot array. Meanwhile, a pair of shorting pins is longitudinally placed at the two symmetrical sides of this central slot to maintain the resonant frequency. Due to the out of phase between the electric fields in the central slot and two sided slots, the far-field radiated by the three slots can be canceled with each other in specific directions away from broadside. Thus, this cancellation results in sidelobe of low level in the E-plane due to emergence of radiation nulls, and further makes the main radiation beam more directionally selective. Accordingly, the directivity and gain of this proposed patch antenna are enhanced with no need of enlarging the overall size of patch. Finally, the simulated and measured results are provided to validate the operating principle and show that the directivity is increased by about 1.7 dB increment.
Autors: Xiao Zhang;Lei Zhu;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5702 - 5709
Publisher: IEEE
 
» Gain-Tunable Complementary Common-Source Amplifier Based on a Flexible Hybrid Thin-Film Transistor Technology
Abstract:
In this letter, we report a flexible complementary common-source (CS) amplifier comprising one p-type spray-coated single walled carbon nanotube and one n-type sputtered InGaZnO4 thin-film transistor (TFT). Bottom-gate TFTs were realized on a free-standing flexible polyimide foil using a maximum process temperature of 150 °C. The resulting CS amplifier operates at 10 V supply voltage and exhibits a gain bandwidth product of 60 kHz. Thanks to the use of a p-type TFT acting as a tunable current source load, the amplifier gain can be programmed from 3.5 up to 27.2 V/V (28.7 dB). To the best of our knowledge, this is the highest gain ever obtained for a flexible single-stage CS amplifier.
Autors: Luisa Petti;Florin Loghin;Giuseppe Cantarella;Christian Vogt;Niko Münzenrieder;Alaa Abdellah;Markus Becherer;Tobias Haeberle;Alwin Daus;Giovanni Salvatore;Gerhard Tröster;Paolo Lugli;
Appeared in: IEEE Electron Device Letters
Publication date: Nov 2017, volume: 38, issue:11, pages: 1536 - 1539
Publisher: IEEE
 
» Gait Velocity and Chair Sit-Stand-Sit Performance Improves Current Frailty-Status Identification
Abstract:
Frailty is characterized by a loss of functionality and is expected to affect 9.9% of people aged 65 and over. Here, current frailty classification is compared with a collection of selected kinematic parameters. A total of 718 elderly subjects (319 males and 399 females; age: 75.4 ± 6.1 years), volunteered to participate in this study and were classified according to Fried’s criteria. Both the 30-s chair stand test (CST) and the 3-m walking test were performed and a set of kinematic parameters were obtained from a single inertial unit. A decision tree analysis was used to: 1) identify the most relevant frailty-related parameters and 2) compare validity of this classification. We found that a selected set of parameters from the 30-s CST (i.e., range of movement, acceleration, and power) were better at identifying frailty status than both the actual outcome of the test (i.e., cycles’ number) and the normally used criteria (i.e., gait speed). For the pre-frail status, AUC improves from 0.531 using the actual test outcome and 0.516 with gait speed to 0.938 with the kinematic parameters criteria. In practice, this could improve the presyndrome identification and perform the appropriate actions to postpone the progression into the frail status.
Autors: Nora Millor;Pablo Lecumberri;Marisol Gómez;Alicia Martinez;Jon Martinikorena;L. Rodríguez-Mañas;F. J. García-García;Mikel Izquierdo;
Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Publication date: Nov 2017, volume: 25, issue:11, pages: 2018 - 2025
Publisher: IEEE
 
» Gamesman Problems [Gamesman Problems]
Abstract:
Autors: Athanasios Kakarountas;
Appeared in: IEEE Potentials
Publication date: Nov 2017, volume: 36, issue:6, pages: 48 - 48
Publisher: IEEE
 
» Gamesman Solutions [Gamesman Solutions]
Abstract:
Autors: Athanasios Kakarountas;
Appeared in: IEEE Potentials
Publication date: Nov 2017, volume: 36, issue:6, pages: 5 - 5
Publisher: IEEE
 
» GaN Membrane Supported SAW Pressure Sensors With Embedded Temperature Sensing Capability
Abstract:
This paper presents the fabrication and characterization of a GHz operating surface acoustic wave (SAW)-based pressure sensor on a 1.2--thin GaN membrane. Two types of interdigitated transducers are manufactured using electron beam nanolithography to obtain finger and interdigit spacing widths, one with 170 nm and the other 200-nm-half pitch. Micromachining techniques are used to obtain the 1.2--thin membrane. The resonance frequency shift of the SAW, the pressure sensitivity, , as well as the pressure coefficient of frequency (PCF), were experimentally determined and analyzed, both for the Rayleigh as well as for the symmetrical Lamb propagation mode, in the 1 to 7 Bar pressure range. Record values for (up to 6 MHz/Bar) and PCF (up to 537 ppm/Bar) have been obtained, especially for the symmetrical Lamb propagation mode also due to the very high frequency operation (5–11.5 GHz). The effect of different orientations of the SAW device (in the and directions) on the frequency response and sensitivity is also analyzed. The possibility to determine simultaneously the pressure and the temperature with the same SAW structure operating as a dual sensor has been demonstrated.
Autors: Alexandru Müller;George Konstantinidis;Ioana Giangu;Gina C. Adam;Alexandra Stefanescu;Antonis Stavrinidis;George Stavrinidis;Athanasios Kostopoulos;George Boldeiu;Adrian Dinescu;
Appeared in: IEEE Sensors Journal
Publication date: Nov 2017, volume: 17, issue:22, pages: 7383 - 7393
Publisher: IEEE
 
» Gas–Liquid Two-Phase Flow Velocity Measurement With Continuous Wave Ultrasonic Doppler and Conductance Sensor
Abstract:
Flow velocity is an important process parameter that quantifies the volume or mass flow rate as well as monitors the process safety. To nonintrusively measure the flow velocity of horizontal gas-liquid two-phase flow, an ultrasonic Doppler sensor and a conductance sensor with dedicated measurement models are presented. The air superficial flow velocity can be directly obtained and the water superficial flow velocity can be calculated through a two-fluid model for bubble flow and plug flow. For slug flow, a correlation between the phase velocity in slug body and overall superficial flow velocity was built based on a slug closure model. In order to eliminate the influence of the changing velocity profile in the fluid, the sample volume was designed to cover the whole pipe cross section by installing a two-chip piezoelectric transducer with 1-MHz center frequency at the bottom of the pipe. The conductance sensor provided water holdup estimate to compensate the velocity measurement model. Experiments were carried out in a 50-mm inner diameter pipe to verify the proposed sensor and model. Three flow patterns (bubble flow, plug flow, and slug flow) were generated by adjusting the inlet flow rate of the air and the water. The results show that the mean relative error can achieve within 5%.
Autors: Xiaoxiao Dong;Chao Tan;Feng Dong;
Appeared in: IEEE Transactions on Instrumentation and Measurement
Publication date: Nov 2017, volume: 66, issue:11, pages: 3064 - 3076
Publisher: IEEE
 
» Gate Swing Improving for the Nothing on Insulator Transistor in Weak Tunneling
Abstract:
One of the most controversial parameter of the nothing on insulator (NOI) transistor was the subthreshold gate swing-SS. Therefore, the main purpose of this paper is to considerably improve the swing value by simulations from the previously reported 1.2 V/dec to 200 mV/dec. The first condition is to operate the NOI transistor in weak tunneling. The second strategy is to change the NOI structure: the bottom oxide thinning, the doping profile optimization, and the source geometry changing. In addition to the SS decreasing, other parameters for digital applications are improved: ION/IOFF ratio increases to 1011, threshold voltage decreases in inversion to –1 V and the switch time under the gate command reaches to 10 ps.
Autors: Cristian Ravariu;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Nov 2017, volume: 16, issue:6, pages: 1115 - 1121
Publisher: IEEE
 
» Gd5Si4 Micro- and Nano-Particles for Self-Regulated Magnetic Hyperthermia
Abstract:
Gd5Si4 is a promising candidate for magnetic hyperthermia because its is near the therapeutic range and is tuneable, opening the door for self-regulated hyperthermia, which is limited from overheating by . In addition, Gd5Si4 has a high saturation magnetization and is potentially biocompatible. In this paper, Gd5Si4 particles were fabricated by a scalable top–down approach of arc-melting and ball-milling. The particles have an average size of 900 nm and a wide size range. Magnetization measurements show that the magnetic transition is broadened and the transition temperature is somewhat reduced from the bulk value of 63 °C to 50 °C, which is very close to the maximum desired hyperthermia temperature range of 43 °C–45 °C. Hyperthermia measurements were performed in an alternating magnetic field. Specific loss power was calculated from the slope of the heating curve; the maximum value was 18 W/g at 0.064 T and 213 kHz. Self-regulated heating behavior was demonstrated, with maximum temperatures approaching 47 °C for the largest fields, close to the measured magnetic transition temperature .
Autors: Z. Boekelheide;Z. A. Hussein;S. M. Harstad;A. A. El-Gendy;R. L. Hadimani;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 4
Publisher: IEEE
 
» Generation of Circularly Polarized Conical Beam Pattern Using Torus Knot Antenna
Abstract:
A wideband circularly polarized antenna with a conical beam radiation pattern is presented. It consists of a torus knot as a radiator and a feeding probe to excite it. The proposed feeding mechanism is simple and does not use power divider network to generate circular polarization (CP). Characteristic mode analysis of a knot shows that a particular kind of knot, with a suitable excitation, can radiate omnidirectional beam with CP. To validate the design, a prototype of torus knot antenna is realized using additive manufacturing technology. The return loss, radiation pattern, and axial ratio (AR) are measured. A parametric study is carried out to understand the effect of various geometric parameters on the performance of the antenna. The fabricated torus knot antenna has a usable bandwidth of 51.8% and the measured AR bandwidth is 66%.
Autors: S. Vinoth Kumar;A. R. Harish;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Nov 2017, volume: 65, issue:11, pages: 5740 - 5746
Publisher: IEEE
 
» Geometric Graph Matching Using Monte Carlo Tree Search
Abstract:
We present an efficient matching method for generalized geometric graphs. Such graphs consist of vertices in space connected by curves and can represent many real world structures such as road networks in remote sensing, or vessel networks in medical imaging. Graph matching can be used for very fast and possibly multimodal registration of images of these structures. We formulate the matching problem as a single player game solved using Monte Carlo Tree Search, which automatically balances exploring new possible matches and extending existing matches. Our method can handle partial matches, topological differences, geometrical distortion, does not use appearance information and does not require an initial alignment. Moreover, our method is very efficient—it can match graphs with thousands of nodes, which is an order of magnitude better than the best competing method, and the matching only takes a few seconds.
Autors: Miguel Amável Pinheiro;Jan Kybic;Pascal Fua;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Nov 2017, volume: 39, issue:11, pages: 2171 - 2185
Publisher: IEEE
 
» Geometry-Based Pectoral Muscle Segmentation From MLO Mammogram Views
Abstract:
Computer-aided diagnosis systems (CADx) play a major role in the early diagnosis of breast cancer. Extracting the breast region precisely from a mammogram is an essential component of CADx for mammography. The appearance of the pectoral muscle on medio-lateral oblique (MLO) views increases the false positive rate in CADx. Therefore, the pectoral muscle should be identified and removed from the breast region in an MLO image before further analysis. None of the previous pectoral muscle segmentation methods address all breast types based on the breast imaging-reporting and data system tissue density classes. In this paper, we deal with this deficiency by introducing a new simple yet effective method that combines geometric rules with a region growing algorithm to support the segmentation of all types of pectoral muscles (normal, convex, concave, and combinatorial). Experimental segmentation accuracy results were reported for four tissue density classes on 872 MLO images from three publicly available datasets. An average Jaccard index and Dice similarity coefficient of 0.972 ± 0.003 and 0.985 ± 0.001 were obtained, respectively. The mean Hausdorff distance between the contours detected by our method and the ground truth is below 5 mm for all datasets. An average acceptable segmentation rate of ∼95% was achieved outperforming several state-of-the-art competing methods. Excellent results were obtained even for the most challenging class of extremely dense breasts.
Autors: Saeid Asgari Taghanaki;Yonghuai Liu;Brandon Miles;Ghassan Hamarneh;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Nov 2017, volume: 64, issue:11, pages: 2662 - 2671
Publisher: IEEE
 
» Germanium Quantum Well QCSE Waveguide Modulator With Tapered Coupling in Distributed Modulator–Detector System
Abstract:
Optical interconnections (interconnects) have been proposed as solutions to the ever-increasing bandwidth requirements and energy consumption in communication systems. Among possible photonic modulation strategies, the Ge quantum well (QW) based quantum-confined Stark effect (QCSE) stands out, as its strong electro-absorption effect allows for potentially lower power consumption and smaller device sizes compared to other modulation mechanisms. Here, we experimentally demonstrate a thin buffer layer Ge QW QCSE waveguide modulator that evanescently couples to and from an Si waveguide through an adiabatic three-dimensional (3D) taper. Simulations confirm that this 3-D taper yields higher coupling efficiency and improved maintenance of the fundamental mode after coupling compared to a 2-D taper. We also demonstrate that this geometry could potentially work in an integrated modulator-detector system. The combination of thin SiGe epitaxy (i.e., the buffer and device layers) with Si waveguides paves the way to easier integration of Si photonic integrated circuits.
Autors: Kai Zang;Ching-Ying Lu;Xiaochi Chen;Edward Fei;Muyu Xue;Stephanie Claussen;Matthew Morea;Yusi Chen;Raj Dutt;Yijie Huo;Theodore I. Kamins;James S. Harris;
Appeared in: Journal of Lightwave Technology
Publication date: Nov 2017, volume: 35, issue:21, pages: 4629 - 4633
Publisher: IEEE
 
» Global Stabilization of Stochastic Nonlinear Systems Via $C^1$ and $C^{infty }$ Controllers
Abstract:
The problem of designing or controllers for a class of stochastic nonlinear systems (SNSs) in lower-triangular form is studied in this note. By using the well-known backstepping method, the concept of homogeneity with monotone degrees (HWMD) and the sign function approach, we construct a state feedback controller recursively. Meanwhile, by employing a polynomial Lyapunov function with sign functions, we prove that the solution to SNSs is globally asymptotically stable in probability. Furthermore, based on the concept of HWMD, it shows that controllers for a class of three-dimensional SNSs can be modified to controllers under certain conditions. Finally, two simulation examples are given to demonstrate the effectiveness of the proposed controllers.
Autors: Hui Wang;Quanxin Zhu;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Nov 2017, volume: 62, issue:11, pages: 5880 - 5887
Publisher: IEEE
 
» Gold Nanoparticles Biosynthesis: A Simple Route for Control Size Using Waste Peel Extract
Abstract:
The production of gold nanoparticles using the aqueous peel extract of Garcinia mangostana plant is presented in this paper. The amount of peels powder and concentration of tetrachloroaurate salt were altered to determine the effect toward the nanoparticles. When the concentration of the starting materials increased, sharper peaks were observed in UV-vis spectroscopy at the region of 530 nm. The nanoparticles produced were spherical in shape with peel extract matrix surrounding them to prevent aggregation. The average size of the nanoparticles was 47.92±4.92 nm. The presence of gold nanoparticles with face centered cubic structure was confirmed by using XRD. The nanoparticles produced were relatively stable with a stability of –18.45 mV. This paper presents a facile and simple way to produce nontoxic nanoparticles that are environmental friendly and cost effective.
Autors: Kar Xin Lee;Kamyar Shameli;Mikio Miyake;Nurul Bahiyah Bt Ahmad Khairudin;Shaza Eva Bt Mohamad;Hirofumi Hara;Mariam Firdhaus Bt Mad Nordin;Yen Pin Yew;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Nov 2017, volume: 16, issue:6, pages: 954 - 957
Publisher: IEEE
 
» Goos–Hänchen Shift of a Spin-Wave Beam at the Interface Between Two Ferromagnets
Abstract:
Spin waves (SWs) are promising information carriers which can be used in modern magnonic devices, characterized by higher performance and lower energy consumption than presently used electronic circuits. However, before practical application of SWs, the efficient control over SW amplitude and phase needs to be developed. We analytically analyze reflection and refraction of the SWs at the interface between two ferromagnetic (FM) materials. In the model, we consider the system consisting of two semi-infinite FM media, separated by the ultra-narrow interface region with the magnetic anisotropy. We have found the Goos–Hänchen (GH) shift for SWs in transmission and reflection, and performed detailed investigations of its dependence on the anisotropy at the interface and materials surrounding the interface. We have demonstrated the possibility of obtaining GH shift of several wavelengths in reflection for realistic material parameters. That proves the possibility for change of the SWs phase in FM materials at sub-wavelength distances, which can be regarded as a metasurface for magnonics.
Autors: Marina Mailyan;Pawel Gruszecki;Oksana Gorobets;Maciej Krawczyk;
Appeared in: IEEE Transactions on Magnetics
Publication date: Nov 2017, volume: 53, issue:11, pages: 1 - 5
Publisher: IEEE
 
» Government Adopts an Industry Approach to Open Source Collaboration
Abstract:
In response to recent increases in massive identity-centric security breaches, NIST has released a significant update to Special Publication 800-63, Digital Identity Guidelines, which lays out technical and procedural requirements for US federal agencies that need to authenticate users accessing their digital services. This update took a new approach—open source document development—to more intimately involve stakeholders in the revision effort.
Autors: Paul Grassi;Mike Garcia;Katie Boeckl;
Appeared in: Computer
Publication date: Nov 2017, volume: 50, issue:11, pages: 78 - 81
Publisher: IEEE
 
» GPU Accelerated FFT-Based Registration of Hyperspectral Scenes
Abstract:
Registration is a fundamental previous task in many applications of hyperspectrometry. Most of the algorithms developed are designed to work with RGB images and ignore the execution time. This paper presents a phase correlation algorithm on GPU to register two remote sensing hyperspectral images. The proposed algorithm is based on principal component analysis, multilayer fractional Fourier transform, combination of log-polar maps, and peak processing. It is fully developed in CUDA for NVIDIA GPUs. Different techniques such as the efficient use of the memory hierarchy, the use of CUDA libraries, and the maximization of the occupancy have been applied to reach the best performance on GPU. The algorithm is robust achieving speedups in GPU of up to .
Autors: Álvaro Ordóñez;Francisco Argüello;Dora B. Heras;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Nov 2017, volume: 10, issue:11, pages: 4869 - 4878
Publisher: IEEE
 

Publication archives by date

  2017:   January     February     March     April     May     June     July     August     September     October     November     December    

  2016:   January     February     March     April     May     June     July     August     September     October     November     December    

  2015:   January     February     March     April     May     June     July     August     September     October     November     December    

  2014:   January     February     March     April     May     June     July     August     September     October     November     December    

  2013:   January     February     March     April     May     June     July     August     September     October     November     December    

  2012:   January     February     March     April     May     June     July     August     September     October     November     December    

  2011:   January     February     March     April     May     June     July     August     September     October     November     December    

  2010:   January     February     March     April     May     June     July     August     September     October     November     December    

  2009:   January     February     March     April     May     June     July     August     September     October     November     December    

 
0-C     D-L     M-R     S-Z