Electrical and Electronics Engineering publications abstract of: 01-2017 sorted by title, page: 7

» Environmental Generation Scheduling Considering Air Pollution Control Technologies and Weather Effects
Abstract:
Because the power industry makes a significant contribution to air pollution, a variety of air pollution control technologies have been adopted to reduce emissions of nitrogen oxides, sulfur dioxide, and particulate matters. However, the deployment of these technologies affects the operation of the power plants and of the power system. This paper first discusses the emissions of multiple pollutants by coal- and gas-fired generators equipped with different emission control devices. It then presents the formulation of an environmental power generation scheduling (EnPGS) model, which coordinates the operating cost and the emissions of these pollutants, including the emissions during the startup and shutdown processes. This model considers the air quality index and how this index is affected by the weather, and optimizes the spatial distribution of generation between regions. It also takes into account the operating characteristics of various emission control devices, such as the deactivation of selective catalytic reduction at low output, and the burn mode switching of combined cycle gas turbines. A case study covering several Chinese provinces demonstrates the potential effectiveness of the EnPGS at reducing multiple air pollutants.
Autors: Zhaowei Geng;Qixin Chen;Qing Xia;Daniel S. Kirschen;Chongqing Kang;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2017, volume: 32, issue:1, pages: 127 - 136
Publisher: IEEE
 
» Environmentally Stable Pulse Energy-Tunable Picosecond Fiber Laser
Abstract:
We have reported a mode-locked pulse energy tunable ytterbium-doped fiber laser constructed by the polarization-maintaining (PM) fibers with a position-tunable focuser and a semiconductor-saturable absorber mirror (SESAM). The narrow bandwidth fiber Bragg grating in the cavity produces self-starting picosecond (ps) mode-locked operation. The linear laser cavity achieved tunable single pulse energy varied from 0.591 to 0.988 nJ, with a 24.7-MHz repetition rate and a 6.03-ps pulse duration at 1064.18 nm. High environmental stability is also confirmed by a high polarization extinction ratio over 17.8 dB.
Autors: Yang Wang;Bao-Le Lu;Xin-Yuan Qi;Lei Hou;Jin Kang;Ke-Xun Huang;Xiao-Qiang Feng;Dian-Lin Zhang;Hao-Wei Chen;Jin-Tao Bai;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2017, volume: 29, issue:1, pages: 150 - 153
Publisher: IEEE
 
» Equal Interference Power Allocation for Efficient Shared Spectrum Resource Scheduling
Abstract:
Effective radio frequency spectrum sharing methods are crucial for sustaining growth and development in mobile wireless services. In this paper, we consider a real-world scenario involving spectrum sharing between mobile wireless and meteorological satellite services as motivation for examining the general problem of efficient resource scheduling in a shared spectrum environment. We formulate an optimization framework for maximizing network utility subject to stochastic interference protection constraints. We design and propose a novel solution inspired by analysis of the optimization problem, where the primary contribution is an efficient power allocation algorithm to manage interference between systems. Using theory and simulations, we show that our algorithm significantly outperforms alternative approaches by well approximating the optimal solution with low enough complexity for practical, real-time application to large networks.
Autors: Matthew A. Clark;Konstantinos Psounis;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Jan 2017, volume: 16, issue:1, pages: 58 - 72
Publisher: IEEE
 
» Equivalence of Frequency-Domain Turbo Equalization Schemes for Single-Carrier Multiple-Input–Multiple-Output Systems
Abstract:
This paper investigates two typical frequency-domain turbo equalization (FDTE) schemes, i.e., frequency-domain equalization (FDE) with parallel interference cancelation (FDE-PIC) and FDE with frequency-domain decision feedback (FDE-FDDF) in single-carrier (SC) multiple-input–multiple-output (MIMO) systems. These two FDTE schemes are proven to be equivalent under the condition that we derived. We discover that the covariance matrix of the low-complexity FDE-PIC scheme and the correlation matrix of the FDE-FDDF scheme satisfy a unique relationship for constant-modulus modulations, and the original FDE-FDDF scheme suffers numerical instability for non-constant-modulus modulations because the estimation of the correlation matrices leads to the inversion of ill-conditioned matrices. By proposing a new estimation method of the correlation matrices, we guarantee that the non-constant-modulus FDE-FDDF scheme is numerically stable and that the relationship between these two FDTE schemes holds for both constant-modulus and non-constant-modulus modulations. Furthermore, we prove that the FDE-PIC and FDE-FDDF schemes are equivalent under this relationship. The equivalence of these two FDTE schemes is also verified through numerical simulations in terms of bit error rate (BER) at each turbo iteration and the estimation of the correlation matrices.
Autors: Zhenrui Chen;Yahong Rosa Zheng;Jintao Wang;Jian Song;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Jan 2017, volume: 66, issue:1, pages: 95 - 106
Publisher: IEEE
 
» Error Analysis of Customer Baseline Load (CBL) Calculation Methods for Residential Customers
Abstract:
Federal Energy Regulatory Commission (FERC) 745 order has created an environment that allows demand response owners to sell their load reduction in the wholesale market. One of the main challenges that independent system operators and utilities face is developing customer baseline load (CBL) calculation methods that work satisfactorily in this new environment. Consequently, it is critical that these methods need to be evaluated from the error performance's perspective. In this paper, error analysis of CBL calculation methods for residential customers is carried out theoretically and empirically. To perform theoretical analysis, the utility function of customers is analyzed to determine the existence of the economic incentives for gaming and inefficient consumption as well as studying the impact of inaccuracy on the social welfare loss. Furthermore, to perform the empirical analysis, well-established CBL calculation methods, HighXofY (New York ISO, well known as NYISO), LowXofY, MidXofY, exponential moving average (New England ISO, well known as ISONE), and regression are first introduced and, then, utilized to calculate the CBL. A dataset consisting of 262 residential customers is used for this analysis. In addition, the error analysis is performed using accuracy and bias metrics. To reach a valid conclusion about the overall performance of CBL methods, an economic analysis of a hypothetical peak time rebate (PTR) program is carried out. According to the results of the case study, the utility pays at least half of its revenue as a rebate solely due to inaccuracy of CBL methods. In addition, it is demonstrated that PTR creates inefficiencies in the residential sector because of the failure of CBL calculation methods to accurately predict the customers’ load profile on the event day.
Autors: Saeed Mohajeryami;Milad Doostan;Ailin Asadinejad;Peter Schwarz;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Jan 2017, volume: 53, issue:1, pages: 5 - 14
Publisher: IEEE
 
» Error Vector Magnitude Analysis of Uplink Multiuser OFDMA and SC-FDMA Systems in the Presence of Nonlinear Distortion
Abstract:
We analyze the impact of nonlinear distortion on the performance of uplink multiuser orthogonal frequency division multiple access and single carrier-frequency division multiple access systems in terms of the error vector magnitude (EVM). Based on the power spectrum density of the distortion noise, we derive a unified framework of theoretical EVM for both systems. The obtained results provide us approaches to evaluation of both the self-distortion and the inter-distortion interference from other users. In addition, simulation results agree well with our theoretical analyses.
Autors: Kun Wu;Guangliang Ren;Qiwei Wang;
Appeared in: IEEE Communications Letters
Publication date: Jan 2017, volume: 21, issue:1, pages: 172 - 175
Publisher: IEEE
 
» Error-Based ILU Preconditioner for the Solution of Linear Equations
Abstract:
There are several types of ILU preconditioners based on different fill-in dropping rules that can be used. One must assure that the chosen preconditioner is suitable for the problem, but this is not frequently an easy task. A bad choice will lower the GMRES convergence rate, increasing the floating point operations and GMRES iteration as well, or even fail. Based on that, this paper proposes a fill-in dropping rule to construct an ILU preconditioner for solution of linear equations via GMRES. The rule is based on reducing error in incomplete triangular factors related to full factors and on Doolittle's Method for LU factorization and allows efficient control of nonzero elements (fill-in) in order to improve the preconditioner quality and GMRES performance as well. The resulting preconditioner is referred to as ILUD (D stands for Doolittle) and it is tested on real power systems; single and sequential load flows (associated to multiple simulations - contingency analysis). The results corroborate the simplicity, efficiency, high quality, and robustness of the ILUD preconditioner.
Autors: Carlos E. Portugal Poma;Ricardo B. Prada;José Eduardo O. Pessanha;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2017, volume: 32, issue:1, pages: 326 - 333
Publisher: IEEE
 
» Errors-in-Variables Anisotropic Extended Orthogonal Procrustes Analysis
Abstract:
This letter presents a novel total least squares (TLS) solution of the anisotropic row-scaling Procrustes problem. The ordinary LS Procrustes approach finds the transformation parameters between origin and destination sets of observations minimizing errors affecting only the destination one. In this letter, we introduce the errors-in-variables model in the anisotropic Procrustes analysis problem and present a solution that can deal with the uncertainty affecting both sets of observations. The algorithm is applied to solve the image exterior orientation problem. Experiments show that the proposed TLS method leads to an accuracy in the parameters estimation that is higher than the one reached with the ordinary LS anisotropic Procrustes solution when the number of points, whose coordinates are known in both the image and the external systems, is small.
Autors: Eleonora Maset;Fabio Crosilla;Andrea Fusiello;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Jan 2017, volume: 14, issue:1, pages: 57 - 61
Publisher: IEEE
 
» ESD Behavior of Tunnel FET Devices
Abstract:
For the first time, we present the electrostatic discharge (ESD) behavior of grounded gate tunnel FET (ggTFET) with detailed physical insight into the device operation, 3-D filamentation and failure under ESD stress conditions. Current as well as time evolution of the junction breakdown, device turn-ON, voltage snapback, and finally the unique failure mechanism is studied using both 2-D and 3-D technology computer aided design simulations. The interaction between the band-to-band tunneling, avalanche multiplication, and thermal carrier generation leading to voltage snapback and failure is presented in detail. In addition, electro-thermal instability initiated filamentation and snapback discovered in the ggTFET is explained. The impact of various technology and device design parameters on the ESD behavior and robustness of TFETs is discussed. This has helped developing guidelines to design ESD robust TFETs for efficient protection concepts. Finally, the charge device model behavior of ggTFET device is discussed.
Autors: Nagothu Karmel Kranthi;Mayank Shrivastava;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Jan 2017, volume: 64, issue:1, pages: 28 - 36
Publisher: IEEE
 
» Estimating Renyi Entropy of Discrete Distributions
Abstract:
It was shown recently that estimating the Shannon entropy of a discrete -symbol distribution requires samples, a number that grows near-linearly in the support size. In many applications, can be replaced by the more general Rényi entropy of order and . We determine the number of samples needed to estimate for all , showing that requires a super-linear, roughly samples, noninteger requires a near-linear samples, but, perhaps surprisingly, integer requires only samples. Furthermore, developing on a recently established connection between polynomial approximation and estimation of additive functions of the form , we reduce the sample complexity for noninteger values of by a factor of compared with the empirical estimator. The estimators achieving these bounds are simple and run in time linear in the number of samples. Our lower bounds provide explicit constructions of distributions with different Rényi entropies that are hard to distinguish.
Autors: Jayadev Acharya;Alon Orlitsky;Ananda Theertha Suresh;Himanshu Tyagi;
Appeared in: IEEE Transactions on Information Theory
Publication date: Jan 2017, volume: 63, issue:1, pages: 38 - 56
Publisher: IEEE
 
» Estimation of Rice Crop Height From X- and C-Band PolSAR by Metamodel-Based Optimization
Abstract:
Rice crops are important in global food economy and are monitored by precise agricultural methods, in which crop morphology in high spatial resolution becomes the point of interest. Synthetic aperture radar (SAR) technology is being used for such agricultural purposes. Using polarimetric SAR (PolSAR) data, plant morphology dependent electromagnetic scattering models can be used to approximate the backscattering behaviors of the crops. However, the inversion of such models for the morphology estimation is complex, ill-posed, and computationally expensive. Here, a metamodel-based probabilistic inversion algorithm is proposed to invert the morphology-based scattering model for the crop biophysical parameter mainly focusing on the crop height estimation. The accuracy of the proposed approach is tested with ground measured biophysical parameters on rice fields in two different bands (X and C) and several channel combinations. Results show that in C-band the combination of the HH and VV channels has the highest overall accuracy through the crop growth cycle. Finally, the proposed metamodel-based probabilistic biophysical parameter retrieval algorithm allows estimation of rice crop height using PolSAR data with high accuracy and low computation cost. This research provides a new perspective on the use of PolSAR data in modern precise agriculture studies.
Autors: Onur Yuzugullu;Esra Erten;Irena Hajnsek;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Jan 2017, volume: 10, issue:1, pages: 194 - 204
Publisher: IEEE
 
» Estimation of Snow Surface Dielectric Constant From Polarimetric SAR Data
Abstract:
A novel methodology is proposed in this paper for the estimation of snow surface dielectric constant from polarimetric SAR (PolSAR) data. The dominant scattering-type magnitude proposed by Touzi et al. is used to characterize scattering mechanism over the snowpack. Two methods have been used to obtain the optimized degree polarization of a partially polarized wave: 1) the Touzi optimum degree of polarization given by Touzi  et al. in 1992. The maximum and the minimum degree of polarizations are obtained along with the optimum transmitted polarizations . 2) The adaptive generalized unitary transformation-based optimum degree of polarization proposed by Bhattacharya  et al. in 2015. This optimum degree of polarization is obtained either by a real or a complex unitary transformation of the 3 3 coherency matrix. These two degrees of polarizations are used and compared in this study as a criterion to select the maximum number of pixels with surface dominant scattering. These pixels were then used to invert the snow surface dielectric constant. It has been observed that the have increased the number of pixels for inversion by compared to the original ata. On the other hand, it was observed that the Touzi maximum degree of polarization has increased the number of pixels for inversion by compared to that of . The proposed methodology is applied to Radarsat-2 PolSAR C-band datasets over the Indian Himalayan region. It is observed that the correlation coefficient between the measured and the estimated snow surface dielectric constant is 0.95 at 95% confidence interval with a root mean square error of 0.20.
Autors: Surendar Manickam;Avik Bhattacharya;Gulab Singh;Yoshio Yamaguchi;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Jan 2017, volume: 10, issue:1, pages: 211 - 218
Publisher: IEEE
 
» European NG112 Crossroads: Toward a New Emergency Communications Framework
Abstract:
Nowadays, citizens are getting used to new ways of agile communications supporting media-enriched and context-aware information. However, the adoption of these evolved technologies in emergency communications between citizens and public authorities faces a series of barriers, including the lack of harmonized and interoperable solutions. Different initiatives worldwide are addressing the need for specifying a stable IP-based next generation emergency communications framework. This article provides a general overview of the different international approaches with special focus on the European perspective, where the NG112 architecture has been specified, and it has now entered the testing and evaluation phase.
Autors: Fidel Liberal;Jose Oscar Fajardo;Cristina Lumbreras;Wolfgang Kampichler;
Appeared in: IEEE Communications Magazine
Publication date: Jan 2017, volume: 55, issue:1, pages: 132 - 138
Publisher: IEEE
 
» European-Type Electricity Market Clearing Model Incorporating PUN Orders
Abstract:
A novel model for the clearing of European day-ahead electricity markets, with all associated types of orders, namely simple hourly orders, block orders, complex orders and PUN (“Prezzo Unico Nazionale”) orders is presented in this paper. An iterative algorithm is employed for the market clearing, bearing an inner iteration process for the handling of Paradoxically Accepted block and MIC orders, and an outer iteration process for the handling of PUN orders. During the iterative process a Master Problem and a PUN subproblem are sequentially solved and coordinated, for the efficient handling of all order clearing conditions and market and/or system constraints. The clearing conditions of each order type are explicitly incorporated in the PUN subproblem, formulating a Mixed Complementarity Problem bearing both primal and dual decision variables. The PUN subproblem concerns the sequential clearing of 24 hourly subproblems, employing a special technique for handling the possible inefficiencies due to the myopic nature of the hourly subproblem solutions, leading to enhanced behavior in terms of social surplus with respect to the state-of-the-art day-ahead market clearing solver. The model and the algorithmic process are evaluated in a west-European test case, demonstrating minimal computational requirements and proving its excellent escalation capabilities.
Autors: Dimitris I. Chatzigiannis;Pandelis N. Biskas;Grigoris A. Dourbois;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2017, volume: 32, issue:1, pages: 261 - 273
Publisher: IEEE
 
» Evaluating Different Implementations of Online Junction Temperature Sensing for Switching Power Semiconductors
Abstract:
Switching power semiconductor online junction temperature sensing is essential for device switching performance evaluation, device switching control, and device lifetime optimization. The contribution of this paper is a detailed evaluation of the implementation issues (including circuit invasiveness, hardware integration, signal processing, and so forth) of different online sensing methods. This paper includes sensing methods based on device power dissipation, sensing methods based on the “sensor-on-die technology,” sensing methods based on device on-state analysis, and sensing methods based on device switching transients. Advantages and limits of these methods are also provided.
Autors: He Niu;Robert D. Lorenz;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Jan 2017, volume: 53, issue:1, pages: 391 - 401
Publisher: IEEE
 
» Evaluating Harmonic Distortions in Brushless Doubly Fed Induction Machines
Abstract:
The brushless doubly fed induction machine (DFIM) is a special machine type that is of interest as a generator in wind turbine drive trains. The brushless DFIM has a significant space-harmonic content compared with conventional machine types, due to its construction. This results in additional harmonic distortions, such as torque-ripple and time harmonics. This paper studies the causes and origins of harmonic distortions in the brushless DFIM. Using time- and space-harmonic analysis, an analytical evaluation method is derived to predict the torque ripple frequencies and time-harmonic frequencies in stator and rotor voltages and currents. The evaluation method is applied to a prototype brushless DFIM to demonstrate the severity of harmonic related distortions that can be present in the brushless DFIMs. The evaluation is validated by additional finite-element analysis and measurements. Furthermore, measures are proposed to reduce harmonic distortions. The insight into harmonic distortions in the brushless DFIM and the ability to predict and prevent them must lead to the improved brushless DFIM designs in the future.
Autors: Tim D. Strous;Xuezhou Wang;Henk Polinder;Jan A. Ferreira;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jan 2017, volume: 53, issue:1, pages: 1 - 10
Publisher: IEEE
 
» Evaluation of 28 nm CMOS Receivers at 183 GHz for Space-borne Atmospheric Remote Sensing
Abstract:
This letter discusses the capability of 28 nm CMOS technology to implement receivers at the 183 GHz band enabling the potential of future radiometers for monitoring atmospheric water vapor. To demonstrate the potential of 28 nm for constructing receivers at these frequencies, a prototype LNA and downconverter chip is demonstrated and measurements of both gain and noise performance are presented. The prototype receiver consumes 191 mW of DC power while providing noise temperatures on the order of 2700 K which demonstrates the potential for use in payload restricted cubesats and other small spacecraft platforms.
Autors: Adrian Tang;Yanghyo Kim;Yinuo Xu;Gabriel Virbila;Theodore Reck;M-C Frank Chang;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jan 2017, volume: 27, issue:1, pages: 100 - 102
Publisher: IEEE
 
» Evaluation of Achievable Vehicle-to-Grid Capacity Using Aggregate PEV Model
Abstract:
Large-scale plug-in electric vehicles (PEVs) utilizing vehicle-to-grid (V2G) technology can collectively behave as a storage system under the control of an aggregator, e.g., arbitraging in the energy market and providing ancillary services to the grid. Quantitatively evaluating V2G capacity, i.e., charging and discharging power ranges, for a PEV fleet utilizing V2G technology (which is referred to as a V2G fleet in this paper) ahead of time is of fundamental importance for V2G implementation. However, because of the stochastic characteristics of PEV driving behaviors, charging demands are difficult to forecast, which makes evaluating V2G capacity technically difficult. This paper first establishes an aggregate model of a V2G fleet that employs aggregated parameters to represent energy and power constraints of the entire V2G fleet and, therefore, reduces the difficulty of forecasting. Then, an evaluation method for V2G capacity of large-scale PEVs is developed based on the proposed aggregate model. To make the V2G capacity evaluated in advance achievable while guaranteeing charging demands during real-time operation, a heuristic smart charging strategy is designed. The application of the evaluation method in optimal charge and discharge scheduling for a V2G fleet providing power reserves is illustrated. Numerical simulations are conducted to validate the proposed method.
Autors: Hongcai Zhang;Zechun Hu;Zhiwei Xu;Yonghua Song;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2017, volume: 32, issue:1, pages: 784 - 794
Publisher: IEEE
 
» Evaluation of Relative Entropy for Distributed Passive Detection of Weak Acoustic Signals
Abstract:
Passive detection of weak signals in noise is formulated without assuming a parametric distribution of the received signal statistics. A binary likelihood-ratio test as to whether the probability densities of two candidate noise populations are the same, or significantly different, leads to the comparison of relative entropy with a Neyman-Pearson detection threshold. The method is demonstrated using the acoustical intensity of narrowband signals at the hydrophones of a bottom-mounted horizontal line array, which was deployed during the Transverse Acoustic Variability Experiment. Receiver operating characteristics of the relative entropy detector are compared with those for the mean signal-to-noise ratio on a set of hydrophones. It is found that at large false-alarm rates the relative entropy detector has comparatively inferior performance while remaining competitive in the region of small false-alarm probability. Relative entropy detection is insensitive to statistical dependence among the sensors, but is sensitive to data having nonstationary intensity statistics characteristic of the ocean environment in which it was tested.
Autors: Peter C. Mignerey;Altan Turgut;Jeffrey A. Schindall;David J. Goldstein;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Jan 2017, volume: 42, issue:1, pages: 219 - 230
Publisher: IEEE
 
» Events in IEEE Region 1 [MTT-S Society News]
Abstract:
Presents information on recent events that took pace in IEEE Region 1 involving the MTTS society.
Autors: Charlotte Blair;
Appeared in: IEEE Microwave Magazine
Publication date: Jan 2017, volume: 18, issue:1, pages: 123 - 125
Publisher: IEEE
 
» Exact Random Coding Secrecy Exponents for the Wiretap Channel
Abstract:
We analyze the exact exponential decay rate of the expected amount of information leaked to the wiretapper in Wyner’s wiretap channel setting using wiretap channel codes constructed from both i.i.d. and constant-composition random codes. Our analysis for those sampled from i.i.d. random coding ensemble shows that the previously known achievable secrecy exponent using this ensemble is indeed the exact exponent for an average code in the ensemble. Furthermore, our analysis on wiretap channel codes constructed from the ensemble of constant-composition random codes leads to an exponent which, in addition to being the exact exponent for an average code, is larger than the achievable secrecy exponent that has been established so far in the literature for this ensemble (which in turn was known to be smaller than that achievable by wiretap channel codes sampled from i.i.d. random coding ensemble). We show examples where the exact secrecy exponent for the wiretap channel codes constructed from random constant-composition codes is larger than that of those constructed from i.i.d. random codes and examples where the exact secrecy exponent for the wiretap channel codes constructed from i.i.d. random codes is larger than that of those constructed from constant-composition random codes. We, hence, conclude that, unlike the error correction problem, there is no general ordering between the two random coding ensembles in terms of their secrecy exponent.
Autors: Mani Bastani Parizi;Emre Telatar;Neri Merhav;
Appeared in: IEEE Transactions on Information Theory
Publication date: Jan 2017, volume: 63, issue:1, pages: 509 - 531
Publisher: IEEE
 
» Exact Solutions to Super Resolution on Semi-Algebraic Domains in Higher Dimensions
Abstract:
We investigate the multi-dimensional super resolution problem on closed semi-algebraic domains for various sampling schemes such as Fourier or moments. We present a new semidefinite programming (SDP) formulation of the -minimization in the space of Radon measures in the multi-dimensional frame on semi-algebraic sets. While standard approaches have focused on SDP relaxations of the dual program (a popular approach is based on Gram matrix representations), this paper introduces an exact formulation of the primal -minimization exact recovery problem of super resolution that unleashes standard techniques (such as moment-sum-of-squares hierarchies) to overcome intrinsic limitations of previous works in the literature. Notably, we show that one can exactly solve the super resolution problem in dimension greater than 2 and for a large family of domains described by semi-algebraic sets.
Autors: Yohann De Castro;F. Gamboa;Didier Henrion;J.-B. Lasserre;
Appeared in: IEEE Transactions on Information Theory
Publication date: Jan 2017, volume: 63, issue:1, pages: 621 - 630
Publisher: IEEE
 
» Expanded Constellation Mapping for Enhanced Far-End-Cross-Talk Cancellation in G.fast
Abstract:
We propose the novel concept of expanded constellation mapping (ECM) for maximising the received signal power, while cancelling the far-end-cross-talk in copper-based wireline communications. The goal of ECM is to beneficially map the transmitted symbol vector to its expanded constellation set by carefully exploiting the copper channels’ specific characteristics. To elaborate, ECM is comprised of the control entity and of the match entity, where the former determines how the ECM would be applied, while the latter searches for the best mapping of the transmitted symbol vector to the expanded constellation set. Our numerical results demonstrate that with the aid of the ECM, more than 25-dB power efficiency gain may be achieved over linear vectoring. Similarly, about 20-dB gain may be achieved over non-linear vectoring. From an implementation point of view, the ECM imposes minimal structural changes on G.fast, whilst exhibiting beneficial reconfigurability and compatibility.
Autors: Rong Zhang;Anas F. Al Rawi;Leslie Derek Humphrey;Lajos Hanzo;
Appeared in: IEEE Communications Letters
Publication date: Jan 2017, volume: 21, issue:1, pages: 56 - 59
Publisher: IEEE
 
» Expanded GDoF-optimality Regime of Treating Interference as Noise in the $Mtimes 2$ X-Channel
Abstract:
Treating interference as noise (TIN) as the most appropriate approach in dealing with interference and the conditions on its optimality has attracted the interest of researchers recently. However, our knowledge on necessary and sufficient conditions of TIN is restricted to a few setups with limited number of users. In this paper, we study the optimality of TIN in terms of the generalized degrees of freedom (GDoF) for a fundamental network, namely, the X-channel. To this end, the achievable GDoF of TIN with power allocations at the transmitters is studied. It turns out that the transmit power allocation maximizing the achievable GDOF is given by on–off signaling as long as the receivers use TIN. This leads to two variants of TIN, namely, P2P-TIN and 2-IC-TIN. While in the first variant the X-channel is reduced to a point-to-point (P2P) channel, in the second variant, the setup is reduced to a two-user interference channel in which the receivers use TIN. The optimality of these two variants is studied separately. To this end, novel genie-aided upper bounds on the capacity of the X-channel are established. The conditions on the optimality of P2P-TIN can be summarized as follows. P2P-TIN is GDoF-optimal if there exists a dominant multiple access channel or a dominant broadcast channel embedded in the X channel. Furthermore, the necessary and sufficient conditions on the GDoF-optimality of 2-IC-TIN are presented. Interestingly, it turns out that operating the X-channel in the 2-IC-TIN mode might be still GDOF optimal, although the conditions given by Geng et al. are violated. However, 2-IC-TIN is sub-optimal if there exists a single interferer which causes sufficiently strong interfer nce at both receivers. The comparison of the results with the state of the art shows that the GDOF optimality of TIN is expanded significantldy.
Autors: Soheil Gherekhloo;Anas Chaaban;Aydin Sezgin;
Appeared in: IEEE Transactions on Information Theory
Publication date: Jan 2017, volume: 63, issue:1, pages: 355 - 376
Publisher: IEEE
 
» Expanded Parts Model for Semantic Description of Humans in Still Images
Abstract:
We introduce an Expanded Parts Model (EPM) for recognizing human attributes (e.g., young, short hair, wearing suits) and actions (e.g., running, jumping) in still images. An EPM is a collection of part templates which are learnt discriminatively to explain specific scale-space regions in the images (in human centric coordinates). This is in contrast to current models which consist of a relatively few (i.e., a mixture of) ‘average’ templates. EPM uses only a subset of the parts to score an image and scores the image sparsely in space, i.e., it ignores redundant and random background in an image. To learn our model, we propose an algorithm which automatically mines parts and learns corresponding discriminative templates together with their respective locations from a large number of candidate parts. We validate our method on three recent challenging datasets of human attributes and actions. We obtain convincing qualitative and state-of-the-art quantitative results on the three datasets.
Autors: Gaurav Sharma;Frédéric Jurie;Cordelia Schmid;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Jan 2017, volume: 39, issue:1, pages: 87 - 101
Publisher: IEEE
 
» Expectation Propagation as Turbo Equalizer in ISI Channels
Abstract:
In probabilistic equalization of channels with inter-symbol interference, the BCJR algorithm and its approximations become intractable for high-order modulations, even for moderate channel dispersions. In this paper, we introduce a novel soft equalizer to approximate the symbol a posteriori probabilities (APP), where the expectation propagation (EP) algorithm is used to provide an accurate estimation. This new soft equalizer is presented as a block solution, denoted as block-EP (BEP), where the structure of the matrices involved is exploited to reduce the complexity order to , i.e., linear in the length of the channel, , and quadratic in the frame length, . The solution is presented in complex-valued formulation within a turbo equalization scheme. This algorithm can be cast as a linear minimum-mean-squared-error (LMMSE) turbo equalization with double feedback architecture, where constellations being discrete is a restriction exploited by the EP that provides a first refinement of the APP. In the experiments included, the BEP exhibits a robust performance, regardless of the channel response, with gains in the range 1.5–5 dB compared with the LMMSE equalization.
Autors: Irene Santos;Juan José Murillo-Fuentes;Rafael Boloix-Tortosa;Eva Arias-de-Reyna;Pablo M. Olmos;
Appeared in: IEEE Transactions on Communications
Publication date: Jan 2017, volume: 65, issue:1, pages: 360 - 370
Publisher: IEEE
 
» Experimental Demonstration of SBG Semiconductor Laser With Controlled Phase Shift
Abstract:
We designed and experimentally demonstrated a sampled Bragg grating semiconductor laser with a controllable phase shift. The experimental results indicate that the introduced phase shift can be controlled by tuning injection current. The studied laser has good single longitudinal mode performance of which side mode suppression ratio (SMSR) is even up to 61.1 dB. Under the constant total current of 150 mA, the lasing wavelength can be continuously tuned about 1.1 nm and the SMSR keeps above 40 dB, while the output fluctuates slightly. This laser can be used to design and fabricate multiwavelength laser array for photonic integrated circuits.
Autors: Renjia Guo;Yating Zhou;Hong Xiao;Rui Mao;Yuqiao Shen;Yuechun Shi;Xiangfei Chen;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2017, volume: 29, issue:1, pages: 126 - 129
Publisher: IEEE
 
» Experimental demonstration of upstream transmission in digital filter multiple access pons with real-time reconfigurable optical network units
Abstract:
Digital filter multiple access (DFMA) passive optical networks (PONs) exploit centralized softwaredefined networking (SDN) controller-managed and transceiver-embedded digital orthogonal filters in individual optical network units (ONUs) to enable end-users to adaptively and dynamically access and share a common fiber transmission medium. DFMA PONs have the potential of not only equipping NG-PONs with sufficient network operation flexibility, adaptability, elasticity, and reconfigurability, but also providing highly desirable backward compatibility with current PON standards. In this paper, for the first time to our knowledge, multipoint-to-point upstream signal transmission in intensity-modulation and direct-detection (IMDD)DFMAPONs is experimentally demonstrated using two real-time, reconfigurable, optical orthogonal frequency division multiplexing-modulated ONUs and an offline optical line terminal. The experimental demonstrations show that each ONU achieves a similar upstreambit error rate performance, excellent tolerance to inter-ONU sample timing offset, and a relatively large ONU launch power variation range.
Autors: Xiao Duan;Roger P. Giddings;Sa'ad Mansoor;J. M. Tang;
Appeared in: IEEE/OSA Journal of Optical Communications and Networking
Publication date: Jan 2017, volume: 9, issue:1, pages: 45 - 52
Publisher: IEEE
 
» Experimental Evaluation of WiFi Active Power/Energy Consumption Models for Smartphones
Abstract:
We conduct an extensive experimental evaluation of a class of WiFi active power/energy consumption models for smartphones that are based on parameters readily available to the upper layers of the protocol stack. We first consider a number of parameters used by previous models and show their limitations. We then focus on a recent approach modeling the active power consumption as a function of the application layer throughput. We study the properties of a previously proposed throughput-based model in relation to other parameters such as the packet size and/or the transport layer protocol, and we evaluate its accuracy under a variety of scenarios that have not been considered in previous studies. Our results show that the model works well in a number of scenarios, with both 802.11n- and 802.11ac-equipped smartphones, and its accuracy can be largely improved with the knowledge of transport layer protocol and packet size. However, such knowledge makes the model more complex and results in largely reduced accuracy in high throughput settings or on hardware different from the one that was used for training. We further discuss a few practical issues related to the measurement and modeling methodology.
Autors: Li Sun;Haotian Deng;Ramanujan K. Sheshadri;Wei Zheng;Dimitrios Koutsonikolas;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Jan 2017, volume: 16, issue:1, pages: 115 - 129
Publisher: IEEE
 
» Experimental Studies of the Frequency Dependence of the Low-Barrier Mott Diode Impedance
Abstract:
We study the microwaave impedance of low-barrier Mott diodes with a -doped layer near the metal contact. Parameters of the elements of the diode equivalent circuit are determined and their dependences on the dc bias voltage are examined. The effects of injection of electrons into the i layer and their time delay in the potential well of the layer under a forward bias are discussed. An original method of the incoming test of epitaxial wafers and the diagnostics of their linear characteristics for the epitaxial structures intended for manufacturing of low-barrier Mott diodes is proposed.
Autors: N. V. Vostokov;V. I. Shashkin;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Jan 2017, volume: 64, issue:1, pages: 109 - 114
Publisher: IEEE
 
» Experimental Study of a 2.3-MV Field-Distortion Oil Switch
Abstract:
A 2.3-MV field-distortion oil switch was built and experimentally studied. Based on the JianGuang-I facility in China, an experimental stand was established for tests of the switch. Both static and dynamic performances of the switch were studied in detail. Experiment results show that the switch works well at approximately 2.3 MV with a 350-ns rise time. Field-distortion mechanisms worked well. In addition, the requirements of the trigger-voltage peak were not as rigorous as anticipated. With trigger voltages higher than 75 kV, the switch worked well with no problems. As the trigger voltage increased, the switch-breakdown delay and its jitters decreased rapidly. With a 250-kV trigger voltage, the breakdown delay of the switch was approximately 132 ns. Its jitter (the standard deviation) was as low as 4.4 ns. Finally, electrode erosions of the switch are also presented and analyzed.
Autors: Yixiang Hu;Shuqing Ren;Yuying Zhang;Ai’ci Qiu;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Jan 2017, volume: 45, issue:1, pages: 100 - 105
Publisher: IEEE
 
» Explicit Phase Lead Filter Design in Repetitive Control for Voltage Harmonic Mitigation of VSI-Based Islanded Microgrids
Abstract:
Repetitive control strategies have been commonly applied in pulse-width-modulated (PWM) voltage source inverters (VSIs) for many industrial applications. This paper presents a repetitive controller for voltage harmonic mitigation of VSI-based islanded microgrids. The phase delay in the overall control system, e.g., the delay caused by the digital duty cycle calculation, PWM generation, and repetitive controller, has to be compensated by elaborately designed phase lead filters in order to prevent control performance deterioration and system instability. Nevertheless, quantificational analysis and practical design of the time advance unit in such filters are hardly found in existing literature works. In view of this, this paper proposes an explicit analysis of the phase lead filters and a novel design method of the time advance unit in repetitive controllers to ensure system stability. Moreover, with the help of the proposed method, the overall system stability margin is predictable and improved controller performance is achieved as well. The proposed method is implemented experimentally to show the accurate stability margin calculation as well as the excellent steady state and dynamic performances of the repetitive control scheme.
Autors: Shunfeng Yang;Peng Wang;Yi Tang;Lei Zhang;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Jan 2017, volume: 64, issue:1, pages: 817 - 826
Publisher: IEEE
 
» Exploiting Mobile Big Data: Sources, Features, and Applications
Abstract:
The worldwide rollout of 4G LTE mobile communication networks has accelerated the proliferation of the mobile Internet and spurred a new wave of mobile applications on smartphones. This new wave has provided mobile operators an enormous opportunity to collect a huge amount of data to monitor the technical and transactional aspects of their networks. Recent research on mobile big data mining have shown its great potential for diverse purposes ranging from improving traffic management, enabling personal and contextual services, to monitoring city dynamics and so on. The mobile big data research has a multi-disciplinary nature that demands distinct knowledge from mobile communications, signal processing, and data mining. The research field of mobile big data has emerged quickly in recent years, but is somewhat fragmented. This article aims to provide an integrated picture of this emerging field to bridge multiple disciplines and hopefully to inspire future research.
Autors: Xiang Cheng;Luoyang Fang;Xuemin Hong;Liuqing Yang;
Appeared in: IEEE Network
Publication date: Jan 2017, volume: 31, issue:1, pages: 72 - 79
Publisher: IEEE
 
» Exploiting SDN for integrating green TWDM-PONS and metro networks preserving end-to-end delay
Abstract:
In time and wavelength division multiplexed (TWDM) passive optical networks (PONs), energy efficiency can be traded with increased average frame delay. However, because some IP services have strict end-to-end delay requirements, such increased delay must be compensated in other network segments. To achieve such compensation, an interaction between control and management planes of different network segments is required. So far, such interaction could be achieved only by custom interfaces at the border of each network segment. Recently, software defined networking (SDN) has emerged as a de facto standard to provide a versatile control and management plane for any network segment. This paper proposes and successfully demonstrates an aggregation node based on a lightweight SDN solution scaled to operate as an intranode controller. The node connects a TWDM-PON, which implements an optical line terminalenergy efficient scheme basedondynamic bandwidth andwavelength allocation, and ametro/aggregationnetworkbasedonOpenFlowswitches. Resultsshowthat sleepmode inTWDM-PONcould increase the traffic delayby hundredsofmicroseconds,but,byprioritizingsuchtraffic in the metro network, the delay experienced by it in the metro segment is reduced by at least the same amount. Thus the end-to-end delay is maintained.
Autors: K. Kondepu;A. Sgambelluri;L. Valcarenghi;F. Cugini;P. Castoldi;
Appeared in: IEEE/OSA Journal of Optical Communications and Networking
Publication date: Jan 2017, volume: 9, issue:1, pages: 67 - 74
Publisher: IEEE
 
» Exploring the Effect of the Core Boundary Curvature in Hollow Antiresonant Fibers
Abstract:
Through numerical simulations, we systematically study the leakage loss properties of a simplified novel hollow antiresonant fiber in which the core is surrounded by semi-elliptical elements. These studies lead to new insight into the effect of the curvature of the core boundary in antiresonant fibers. We observe in particular that in our design, there exists an optimum curvature of the elements—which we quantify simply through the aspect ratio of the ellipses—for which the fiber’s leakage loss is minimized. Furthermore, it is shown that elliptical elements can lead to orders of magnitude loss reduction as compared with similar fibers with circular ones.
Autors: Lieke D. van Putten;Eric Numkam Fokoua;Seyed Mohammad A. Mousavi;Walter Belardi;Subhasis Chaudhuri;John V. Badding;Francesco Poletti;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2017, volume: 29, issue:2, pages: 263 - 266
Publisher: IEEE
 
» Exponential Discriminative Locality Alignment for Hyperspectral Image Classification
Abstract:
Metric learning algorithms have been widely applied for hyperspectral image (HSI) dimensionality reduction and classification. One of the metric learning algorithms proposed recently is discriminative locality alignment (DLA). The DLA attacks the distribution nonlinearity of samples, and preserves the discriminative ability. However, the DLA needs to manually adjust a parameter called scaling factor and produce mutually correlated discriminant vectors that may lead to unsatisfactory classification results. In this letter, a modified DLA algorithm, i.e., quotient DLA (QDLA), is proposed to solve the problems outlined previously. Moreover, we extend QDLA to a novel exponential DLA (EDLA) algorithm, which can achieve a more effective transformation from a nonlinear mapping of original data into a new space. The classification results with HSIs demonstrate that the performances of the proposed EDLA are better than other related methods.
Autors: Ya-fei Jia;Yun Tian;Yu-jian Li;Peng-bin Fu;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Jan 2017, volume: 14, issue:1, pages: 33 - 37
Publisher: IEEE
 
» Extended Capabilities of the 3-D Smith Chart With Group Delay and Resonator Quality Factor
Abstract:
This paper extends the capabilities of the 3-D Smith chart for representing positive and negative differential-phase group delay and the associated loaded resonator quality factor, displayed simultaneously with scattering (S)-parameters. Here, mathematical concepts, inspired from elementary differential geometry and topology, are used to implement 3-D projections. It is shown that a condition for a circuit to exploit negative differential-phase group delay is that its S-parameter winding number should be ≥ 0 (relative to its origin). Finally, exemplar network responses that exhibit both positive and negative differential-phase group delay and loaded resonator quality factor are shown with the 3-D Smith chart. The convenience of being able to simultaneously display a wider range of parameters on one visualization platform, with the 3-D Smith chart, may help to speed-up the design and analysis of microwave circuits by the user.
Autors: Andrei A. Muller;Esther Sanabria-Codesal;Alin Moldoveanu;Victor Asavei;Stepan Lucyszyn;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2017, volume: 65, issue:1, pages: 10 - 19
Publisher: IEEE
 
» Extended Modal Gain Measurement in DFB Laser Diodes
Abstract:
A practical method is proposed for complete gain measurement in distributed feedback (DFB) laser diodes. It is non-destructive and does not require any reference device. It includes the whole range of continuous gain values, from its minimum to threshold, passing through the transparency condition. The method requires a single absolute gain measurement for calibration. An example is reported for a DFB preserving Fabry–Perot multi-modes in the sub-threshold regime.
Autors: Massimo Vanzi;Giulia Marcello;Giovanna Mura;Germain Le Galès;Simon Joly;Yannick Deshayes;Laurent Bechou;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2017, volume: 29, issue:2, pages: 197 - 200
Publisher: IEEE
 
» Extended State Observer-Based Sliding-Mode Control for Three-Phase Power Converters
Abstract:
This paper proposes an extended state observer (ESO) based second-order sliding-mode (SOSM) control for three-phase two-level grid-connected power converters. The proposed control technique forces the input currents to track the desired values, which can indirectly regulate the output voltage while achieving a user-defined power factor. The presented approach has two control loops. A current control loop based on an SOSM and a dc-link voltage regulation loop which consists of an ESO plus SOSM. In this work, the load connected to the dc-link capacitor is considered as an external disturbance. An ESO is used to asymptotically reject this external disturbance. Therefore, its design is considered in the control law derivation to achieve a high performance. Theoretical analysis is given to show the closed-loop behavior of the proposed controller and experimental results are presented to validate the control algorithm under a real power converter prototype.
Autors: Jianxing Liu;Sergio Vazquez;Ligang Wu;Abraham Marquez;Huijun Gao;Leopoldo G. Franquelo;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Jan 2017, volume: 64, issue:1, pages: 22 - 31
Publisher: IEEE
 
» Extended-State-Observer-Based Funnel Control for Nonlinear Servomechanisms With Prescribed Tracking Performance
Abstract:
In this paper, an approximation-free funnel feedback controller is proposed for a class of nonlinear servomechanisms to achieve prescribed tracking error performance. An improved funnel function is proposed to guarantee the transient and asymptotic behavior of the tracking error within a given funnel boundary. The proposed funnel function removes the imposed assumption used in conventional funnel controls (e.g., systems with relative degree one or two) and avoids the potential singularity problem in prescribed performance controls. Moreover, an extended state observer (ESO) is used to address the effect of unknown dynamics in the control system (e.g., friction and disturbances), where the ESO parameters can be easily designed based on the control system bandwidth. The stability of the proposed control system with ESO and funnel function is analyzed via the Lyapunov theory. Comparative simulations and experimental results are conducted based on a practical turntable servomechanisms to validate the efficacy of the proposed method.
Autors: Shubo Wang;Xuemei Ren;Jing Na;Tianyi Zeng;
Appeared in: IEEE Transactions on Automation Science and Engineering
Publication date: Jan 2017, volume: 14, issue:1, pages: 98 - 108
Publisher: IEEE
 
» Extension of the QuikSCAT Sea Ice Extent Data Set With OSCAT Data
Abstract:
The Ku-band Oceansat-2 Scatterometer (OSCAT) is very similar to the Quick Scatterometer (QuikSCAT), which operated from 1999 to 2009. OSCAT continues the Ku-band scatterometer data record through 2014 with an overlap of 19 days with QuikSCAT’s mission in 2009. This letter discusses a particular climate application of the time series for sea ice extent observation. In this letter, a QuikSCAT sea ice extent algorithm is modified for OSCAT. Gaps in OSCAT data are accounted for and filled in to support sea ice extent mapping. The OSCAT sea ice extent data are validated with QuikSCAT and Special Sensor Microwave/Imager sea ice extent data.
Autors: Jordan C. Hill;David G. Long;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Jan 2017, volume: 14, issue:1, pages: 92 - 96
Publisher: IEEE
 
» Eyeriss: An Energy-Efficient Reconfigurable Accelerator for Deep Convolutional Neural Networks
Abstract:
Eyeriss is an accelerator for state-of-the-art deep convolutional neural networks (CNNs). It optimizes for the energy efficiency of the entire system, including the accelerator chip and off-chip DRAM, for various CNN shapes by reconfiguring the architecture. CNNs are widely used in modern AI systems but also bring challenges on throughput and energy efficiency to the underlying hardware. This is because its computation requires a large amount of data, creating significant data movement from on-chip and off-chip that is more energy-consuming than computation. Minimizing data movement energy cost for any CNN shape, therefore, is the key to high throughput and energy efficiency. Eyeriss achieves these goals by using a proposed processing dataflow, called row stationary (RS), on a spatial architecture with 168 processing elements. RS dataflow reconfigures the computation mapping of a given shape, which optimizes energy efficiency by maximally reusing data locally to reduce expensive data movement, such as DRAM accesses. Compression and data gating are also applied to further improve energy efficiency. Eyeriss processes the convolutional layers at 35 frames/s and 0.0029 DRAM access/multiply and accumulation (MAC) for AlexNet at 278 mW (batch size ), and 0.7 frames/s and 0.0035 DRAM access/MAC for VGG-16 at 236 mW ().
Autors: Yu-Hsin Chen;Tushar Krishna;Joel S. Emer;Vivienne Sze;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Jan 2017, volume: 52, issue:1, pages: 127 - 138
Publisher: IEEE
 
» Fabrication of Linear Array and Top-Orthogonal-to-Bottom Electrode CMUT Arrays With a Sacrificial Release Process
Abstract:
The microfabrication processes for sacrificial-release-based capacitive micromachined ultrasound transducer arrays are provided with an emphasis on top-orthogonal-to-bottom electrode 2-D arrays. These arrays have significant promise for high-quality 3-D imaging with reduced wiring complexity compared with fully wired arrays. The protocols and best practices are outlined in significant detail along with design considerations and notes of caution for pitfalls and factors impacting yield.
Autors: Benjamin A. Greenlay;Roger J. Zemp;
Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Publication date: Jan 2017, volume: 64, issue:1, pages: 93 - 107
Publisher: IEEE
 
» Fabrication of Two Flow Phantoms for Doppler Ultrasound Imaging
Abstract:
Flow phantoms are widely used in studies associated with Doppler ultrasound measurements, acting as an effective experimental validation system in cardiovascular-related research and in new algorithm/instrumentation development. The development of materials that match the acoustic and mechanical properties of the vascular system is of great interest while designing flow phantoms. Although recipes that meet the flow phantom standard defined by the International Electrotechnical Commission 61685 are already available in the literature, the standard procedure for material preparations and phantom fabrications has not been well established. In this paper, two types of flow phantoms, with and without blood vessel mimic, are described in detail in terms of the material preparation and phantom fabrication. The phantom materials chosen for the two phantoms are from published phantom studies, and their physical properties have been investigated previously. Both the flow phantoms have been scanned by ultrasound scanners and images from different modes are presented. These phantoms may be used in the validation and characterization of Doppler ultrasound measurements in blood vessels with a diameter above 1 mm.
Autors: Xiaowei Zhou;David A. Kenwright;Shiying Wang;John A. Hossack;Peter R. Hoskins;
Appeared in: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Publication date: Jan 2017, volume: 64, issue:1, pages: 53 - 65
Publisher: IEEE
 
» Fabrication of Vertical Silicon Nanotube Array Using Spacer Patterning Technique and Metal-Assisted Chemical Etching
Abstract:
We propose a process combining metal-assisted chemical etching and a spacer patterning technique to fabricate dense, vertical silicon nanotubes (SiNTs) with sub-60 nm wall thickness, which may have potential advantages for various devices. Moreover, we investigate the effect of the etch rate controlled by the mixture solution ratio to obtain SiNTs with ideal morphology. The fabricated high aspect ratio SiNTs exhibit good structural stability, leading to bundle-free arrays, which can be ideal for nanostructure-based suppression of optical reflection.
Autors: Hyeonho Jeong;Junghyung Lee;Cheolkyu Bok;Seok-Hee Lee;Seunghyup Yoo;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Jan 2017, volume: 16, issue:1, pages: 130 - 134
Publisher: IEEE
 
» Face recognition tech goes on trial [Top Tech 2017]
Abstract:
Nimesh Patel, aggrieved user of Facebook and Illinois resident, isn’t naive: He well understands that the social networking company collects information about him. But Facebook went too far for his liking when it collected certain intimate details about his physiognomy, such as how many millimeters of skin lie between his eyebrows, how far the corners of his mouth extend across his cheeks, and dozens of other aspects of his facial geometry that enable the company’s face recognition software to identify him.
Autors: Eliza Strickland;
Appeared in: IEEE Spectrum
Publication date: Jan 2017, volume: 54, issue:1, pages: 40 - 41
Publisher: IEEE
 
» Fair bandwidth allocation algorithm for PONS based on network utility maximization
Abstract:
Network utility maximization (NUM) models have been successfully applied to address multiple resource- allocation problems in communication networks. This paper explores, for the first time to our knowledge, their application to modeling the bandwidth-allocation problem in passive optical networks (PONs) and long-reach PONs. Using the NUM model, we propose the FEx-DBA (fair excess-dynamic bandwidth allocation) algorithm, a new DBA scheme to allow a fair and efficient allocation of the upstream channel capacity. The NUM framework provides the mathematical support to formally define the fairness concept in the resource allocation and the guidelines to devise FEx-DBA. A simulation study is conducted, whereby FEx-DBA is compared to a state-of-the-art proposal. We show that FEx-DBA (i) provides bandwidth guarantees to the users according to the service level agreement (SLA) contracted and fairly distributes the excess bandwidths among them; (ii) has a stable response and fast convergence when traffic or SLAs change, avoiding the oscillations appearing in other proposals; (iii) improves average delay and jitter measures; and (iv) only depends on a reduced set of parameters, which can be easily tuned.
Autors: N. Merayo;P. Pavon-Marino;J. C. Aguado;R. J. Durán;F. Burrull;V. Bueno-Delgado;
Appeared in: IEEE/OSA Journal of Optical Communications and Networking
Publication date: Jan 2017, volume: 9, issue:1, pages: 75 - 86
Publisher: IEEE
 
» Farewell Editorial
Abstract:
Presents the farewell address from the editor of this publication.
Autors: Prasant Mohapatra;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Jan 2017, volume: 16, issue:1, pages: 1 - 1
Publisher: IEEE
 
» Fast and Accurate Calculation of System-Level ESD Noise Coupling to a Signal Trace by PEEC Model Decomposition
Abstract:
A fast and accurate calculation method of system-level electrostatic discharge (ESD) noise coupling based on model decomposition of the partial element equivalent circuit is proposed. The proposed method can significantly reduce the calculation time without loss of accuracy by separating small victim signal traces from large aggressor structures such as ground planes and ESD gun strap. Using the method, the ESD noise coupling at the terminations of a victim signal trace is rigorously calculated and validated with measurements and full-wave simulations in both frequency and time domains.
Autors: Junsik Park;Jongsung Lee;Byongsu Seol;Jingook Kim;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2017, volume: 65, issue:1, pages: 50 - 61
Publisher: IEEE
 
» Fast Online Video Synopsis Based on Potential Collision Graph
Abstract:
Video synopsis is a smart solution to fast browsing and retrieval of raw surveillance data, in which tube rearrangement plays a key role. However, conventional methods for tube rearrangement are based on minimizing a global energy function, which is computational intensive and time consuming. In this letter, we propose a novel tube rearrangement strategy for online video synopsis by analyzing collision relationship between tubes. A potential collision graph (PCG) is constructed to represent the tubes and their potential collision relationship. Based on the PCG, tube rearrangement is achieved by filling the tubes into synopsis video in a deterministic way, which decreases computational complexity. Finally, we incorporate the proposed tube rearrangement into an online framework to generate video synopsis and validate its efficiency with extensive experiments.
Autors: Yi He;Zhiguo Qu;Changxin Gao;Nong Sang;
Appeared in: IEEE Signal Processing Letters
Publication date: Jan 2017, volume: 24, issue:1, pages: 22 - 26
Publisher: IEEE
 
» Fast Registration Methodology for Fastener Assembly of Large-Scale Structure
Abstract:
Fastener assembly is a tedious and time-consuming work because operators have to check assembly manuals and find right fastener for each hole. Hence, this paper aims to develop a three-dimensional (3-D) projection system that projects assembly instruction onto the work piece surface directly to guide operators to assemble. However, in order to project the instruction accurately, the corresponding part of the computer-aided design model of the physical scanned area needs to be attained through the rapid and accurate registration. In order to achieve this goal, first, a high-accuracy and rapid 3-D measurement system is developed; second, a fast registration method based on local multiscale geometric feature vector is proposed to accelerate the registration speed and improve the registration reliability. Experimental results demonstrate the measurement accuracy of the developed system, and verify the feasibility of the proposed registration method. Hence, the proposed method can lead to improved assembly efficiency and decreased error probability, making great contributions to large-scale structure assembly.
Autors: Jing Xu;Rui Chen;Heping Chen;Song Zhang;Ken Chen;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Jan 2017, volume: 64, issue:1, pages: 717 - 726
Publisher: IEEE
 
» Fast Variance Prediction for Iteratively Reconstructed CT Images With Locally Quadratic Regularization
Abstract:
Predicting noise properties of iteratively reconstructed CT images is useful for analyzing reconstruction methods; for example, local noise power spectrum (NPS) predictions may be used to quantify the detectability of an image feature, to design regularization methods, or to determine dynamic tube current adjustment during a CT scan. This paper presents a method for fast prediction of reconstructed image variance and local NPS for statistical reconstruction methods using quadratic or locally quadratic regularization. Previous methods either require impractical computation times to generate an approximate map of the variance of each reconstructed voxel, or are restricted to specific CT geometries. Our method can produce a variance map of the entire image, for locally shift-invariant CT geometries with sufficiently fine angular sampling, using a computation time comparable to a single back-projection. The method requires only the projection data to be used in the reconstruction, not a reconstruction itself, and is reasonably accurate except near image edges where edge-preserving regularization behaves highly nonlinearly. We evaluate the accuracy of our method using reconstructions of both simulated CT data and real CT scans of a thorax phantom.
Autors: Stephen M. Schmitt;Mitchell M. Goodsitt;Jeffrey A. Fessler;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Jan 2017, volume: 36, issue:1, pages: 17 - 26
Publisher: IEEE
 
» Fast Vascular Ultrasound Imaging With Enhanced Spatial Resolution and Background Rejection
Abstract:
Ultrasound super-localization microscopy techniques presented in the last few years enable non-invasive imaging of vascular structures at the capillary level by tracking the flow of ultrasound contrast agents (gas microbubbles). However, these techniques are currently limited by low temporal resolution and long acquisition times. Super-resolution optical fluctuation imaging (SOFI) is a fluorescence microscopy technique enabling sub-diffraction limit imaging with high temporal resolution by calculating high order statistics of the fluctuating optical signal. The aim of this work is to achieve fast acoustic imaging with enhanced resolution by applying the tools used in SOFI to contrast-enhance ultrasound (CEUS) plane-wave scans. The proposed method was tested using numerical simulations and evaluated using two in-vivo rabbit models: scans of healthy kidneys and VX-2 tumor xenografts. Improved spatial resolution was observed with a reduction of up to 50% in the full width half max of the point spread function. In addition, substantial reduction in the background level was achieved compared to standard mean amplitude persistence images, revealing small vascular structures within tumors. The scan duration of the proposed method is less than a second while current super-localization techniques require acquisition duration of several minutes. As a result, the proposed technique may be used to obtain scans with enhanced spatial resolution and high temporal resolution, facilitating flow-dynamics monitoring. Our method can also be applied during a breath-hold, reducing the sensitivity to motion artifacts.
Autors: Avinoam Bar-Zion;Charles Tremblay-Darveau;Oren Solomon;Dan Adam;Yonina C. Eldar;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Jan 2017, volume: 36, issue:1, pages: 169 - 180
Publisher: IEEE
 
» Feasibility of InxGa1–xAs High Mobility Channel for 3-D NAND Memory
Abstract:
Epitaxial InxGa1–xAs is grown by metal organic vapor phase epitaxy as replacement of polycrystalline silicon (Si) channel for high-density 3-D NAND memory applications. The most challenging steps to integrate InxGa1–xAs are thoroughly discussed; their impact on the electrical performances are investigated and the tunnel oxide (TuOx) quality is assessed. InxGa1–xAs channels with a diameter down to ~45 nm and different In concentrations are obtained after using two alternative surface preparation routes: HCl and Cl2. Thanks to the lower thermal budget involved, Cl2 seems the most suitable route to preserve the thickness of the TuOx. InxGa1–xAs channels with In concentration, x, higher than 0.45 have superior conduction properties compared with poly-Si channel, showing higher and transconductance.
Autors: E. Capogreco;A. Subirats;J. G. Lisoni;A. Arreghini;B. Kunert;W. Guo;C.-L. Tan;R. Delhougne;G. Van den bosch;K. De Meyer;A. Furnemont;J. Van Houdt;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Jan 2017, volume: 64, issue:1, pages: 130 - 136
Publisher: IEEE
 
» Federated Internet of Things and Cloud Computing Pervasive Patient Health Monitoring System
Abstract:
The exponentially growing healthcare costs coupled with the increasing interest of patients in receiving care in the comfort of their own homes have prompted a serious need to revolutionize healthcare systems. This has prompted active research in the development of solutions that enable healthcare providers to remotely monitor and evaluate the health of patients in the comfort of their residences. However, existing works lack flexibility, scalability, and energy efficiency. This article presents a pervasive patient health monitoring (PPHM) system infrastructure. PPHM is based on integrated cloud computing and Internet of Things technologies. In order to demonstrate the suitability of the proposed PPHM infrastructure, a case study for real-time monitoring of a patient suffering from congestive heart failure using ECG is presented. Experimental evaluation of the proposed PPHM infrastructure shows that PPHM is a flexible, scalable, and energy-efficient remote patient health monitoring system.
Autors: Jemal H. Abawajy;Mohammad Mehedi Hassan;
Appeared in: IEEE Communications Magazine
Publication date: Jan 2017, volume: 55, issue:1, pages: 48 - 53
Publisher: IEEE
 
» FiDoop-DP: Data Partitioning in Frequent Itemset Mining on Hadoop Clusters
Abstract:
Traditional parallel algorithms for mining frequent itemsets aim to balance load by equally partitioning data among a group of computing nodes. We start this study by discovering a serious performance problem of the existing parallel Frequent Itemset Mining algorithms. Given a large dataset, data partitioning strategies in the existing solutions suffer high communication and mining overhead induced by redundant transactions transmitted among computing nodes. We address this problem by developing a data partitioning approach called FiDoop-DP using the MapReduce programming model. The overarching goal of FiDoop-DP is to boost the performance of parallel Frequent Itemset Mining on Hadoop clusters. At the heart of FiDoop-DP is the Voronoi diagram-based data partitioning technique, which exploits correlations among transactions. Incorporating the similarity metric and the Locality-Sensitive Hashing technique, FiDoop-DP places highly similar transactions into a data partition to improve locality without creating an excessive number of redundant transactions. We implement FiDoop-DP on a 24-node Hadoop cluster, driven by a wide range of datasets created by IBM Quest Market-Basket Synthetic Data Generator. Experimental results reveal that FiDoop-DP is conducive to reducing network and computing loads by the virtue of eliminating redundant transactions on Hadoop nodes. FiDoop-DP significantly improves the performance of the existing parallel frequent-pattern scheme by up to 31 percent with an average of 18 percent.
Autors: Yaling Xun;Jifu Zhang;Xiao Qin;Xujun Zhao;
Appeared in: IEEE Transactions on Parallel and Distributed Systems
Publication date: Jan 2017, volume: 28, issue:1, pages: 101 - 114
Publisher: IEEE
 
» Field-Related Failure of GaN-on-Si HEMTs: Dependence on Device Geometry and Passivation
Abstract:
This paper reports on an extensive analysis of the breakdown of GaN-based Schottky-gated HEMTs submitted to high-voltage stress. The analysis was carried out on transistors with different lengths of the drain-side gate-head (), corresponding to different levels of electric field across the SiN passivation. Based on dc measurements, 2-D simulations, and optical analysis, we demonstrate the following original results: 1) when submitted to high drain voltages (in the OFF-state), the transistors can show catastrophic failure; 2) electroluminescence microscopy indicates the presence of hot-spots on the drain-side of the gate; 2-D simulations support the hypothesis that failure occurs in correspondence of the gate-head, on the drain-side edge, where the electric field in the silicon nitride passivation has its maximum; 3) this hypothesis is confirmed by the results of transmission electron microscope failure analysis that demonstrate the generation of a leakage path between the gate metal and the channel, 4) and by the dependence of the destructive voltage on the value. 5) in addition, we propose and demonstrate an approach for improving the reliability of the devices, i.e., using a graded SiN passivation with increased thickness. The results described in this paper provide important information for the device optimization of Schottky-gated HEMTs.
Autors: I. Rossetto;M. Meneghini;S. Pandey;M. Gajda;G. A. M. Hurkx;J. A. Croon;J. Šonský;G. Meneghesso;E. Zanoni;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Jan 2017, volume: 64, issue:1, pages: 73 - 77
Publisher: IEEE
 
» Finding Equilibria in the Pool-Based Electricity Market With Strategic Wind Power Producers and Network Constraints
Abstract:
This paper proposes a model to find the equilibria in the short-term electricity market with large-scale wind power penetration. The behavior of each strategic player is modeled through a two-stage mathematical problem with equilibrium constraints (MPEC), where the upper-level problem maximizes the profit of the strategic player and the lower-level problem describes the clearing processes of the day-ahead and real-time markets while considering the network constraints. The joint solution of all the MPECs constitutes an equilibrium problem with equilibrium constraints (EPEC). The uncertain wind power production and demand are represented by a set of plausible scenarios. By using the duality theory and Karush–Kuhn–Tucker condition, each MPEC is transferred into a mixed-integer linear programing problem. The Nash equilibria of the electricity market are obtained by solving the EPEC using Game theory and the diagonalization algorithm. Case studies are performed to show the effectiveness of the proposed model.
Autors: Ting Dai;Wei Qiao;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2017, volume: 32, issue:1, pages: 389 - 399
Publisher: IEEE
 
» Finding the Kinematic Base Frame of a Robot by Hand-Eye Calibration Using 3D Position Data
Abstract:
When a robot is required to perform specific tasks defined in the world frame, there is a need for finding the coordinate transformation between the kinematic base frame of the robot and the world frame. The kinematic base frame used by the robot controller to define and evaluate the kinematics may deviate from the mechanical base frame constructed based on structural features. Besides, by using kinematic modeling rules such as the product of exponentials (POE) formula, the base frame can be arbitrarily located, and does not have to be related to any feature of the mechanical structure. As a result, the kinematic base frame cannot be measured directly. This paper proposes to find the kinematic base frame by solving a hand-eye calibration problem using 3D position measurements only, which avoids the inconvenience and inaccuracy of measuring orientations and thus significantly facilitates practical operations. A closed-form solution and an iterative solution are explicitly formulated and proved effective by simulations. Comprehensive analyses of the impact of key parameters to the accuracy of the solution are also carried out, providing four guidelines to better conduct practical operations. Finally, experiments on a 7-DOF industrial robot are performed with an optical tracking system to demonstrate the superiority of the proposed method using position data only over the method using full pose data.
Autors: Liao Wu;Hongliang Ren;
Appeared in: IEEE Transactions on Automation Science and Engineering
Publication date: Jan 2017, volume: 14, issue:1, pages: 314 - 324
Publisher: IEEE
 
» FinFET With Encased Air-Gap Spacers for High-Performance and Low-Energy Circuits
Abstract:
We experimentally demonstrate n-channel bulk FinFET with encased air-gap spacers. Encased air gap in the spacer region is formed by depositing carbon sidewalls, encasing them with silicon nitride (SiN) film and finally removing carbon using mild oxygen plasma. We show that the drive current of air-spacer FinFET is improved by about 40% compared with the baseline bulk FinFET with SiN spacers likely due to enhanced tensile stress in the channel. The parasitic capacitance and ring oscillator delay of FinFET with air-spacers is about 25% and 40% lower compared with that with SiN spacers.
Autors: Angada B. Sachid;Yao-Min Huang;Yi-Ju Chen;Chun-Chi Chen;Darsen D. Lu;Min-Cheng Chen;Chenming Hu;
Appeared in: IEEE Electron Device Letters
Publication date: Jan 2017, volume: 38, issue:1, pages: 16 - 19
Publisher: IEEE
 
» Fingerprint Liveness Detection Using Local Coherence Patterns
Abstract:
In this letter, we propose a novel image descriptor for fingerprint liveness detection using the local coherence of a given image. Based on the observation that materials employed for making fake fingerprints (e.g., silicone, wood glue, etc.) tend to yield the nonuniformity in the captured image due to the replica fabrication process, we focus on the difference of the dispersion in the image gradient field between live and fake fingerprints. More specifically, we propose to define the local patterns of the coherence along the dominant direction, the so-called local coherence patterns, as our features, which are fed into the linear support vector machine (SVM) classifier to determine whether a given fingerprint is fake or not. Experimental results on various datasets show that the proposed image descriptor is effective for fingerprint liveness detection compared to other approaches employed in the literature.
Autors: Wonjun Kim;
Appeared in: IEEE Signal Processing Letters
Publication date: Jan 2017, volume: 24, issue:1, pages: 51 - 55
Publisher: IEEE
 
» Finite-Horizon Throughput Region for Wireless Multi-User Interference Channels
Abstract:
This paper studies a wireless network consisting of multiple transmitter-receiver pairs where interference is treated as noise. Previously, the throughput region of such networks was characterized for either one time slot or an infinite time horizon. We aim to fill the gap by investigating the throughput region for transmissions over a finite time horizon. Unlike the infinite-horizon throughput region, which is simply the convex hull of the throughput region of one time slot, the finite-horizon throughput region is generally non-convex. Instead of directly characterizing all achievable rate-tuples in the finite-horizon throughput region, we propose a metric termed the rate margin, which not only determines whether any given rate-tuple is within the throughput region (i.e., achievable or unachievable), but also tells the amount of scaling that can be done to the given achievable (unachievable) rate-tuple such that the resulting rate-tuple is still within (brought back into) the throughput region. Furthermore, we derive an efficient algorithm to find the rate-achieving policy for any given rate-tuple in the finite-horizon throughput region.
Autors: Yirui Cong;Xiangyun Zhou;Rodney A. Kennedy;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Jan 2017, volume: 16, issue:1, pages: 634 - 646
Publisher: IEEE
 
» Firefly-Algorithm-Inspired Framework With Band Selection and Extreme Learning Machine for Hyperspectral Image Classification
Abstract:
A firefly algorithm (FA) inspired band selection and optimized extreme learning machine (ELM) for hyperspectral image classification is proposed. In this framework, FA is to select a subset of original bands to reduce the complexity of the ELM network. It is also adapted to optimize the parameters in ELM (i.e., regularization coefficient C, Gaussian kernel σ, and hidden number of neurons L). Due to very low complexity of ELM, its classification accuracy can be used as the objective function of FA during band selection and parameter optimization. In the experiments, two hyperspectral image datasets acquired by HYDICE and HYMAP are used, and the experiment results indicate that the proposed method can offer better performance, compared with particle swarm optimization and other related band selection algorithms.
Autors: Hongjun Su;Yue Cai;Qian Du;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Jan 2017, volume: 10, issue:1, pages: 309 - 320
Publisher: IEEE
 
» First Principles Investigation of Small Molecules Adsorption on Antimonene
Abstract:
The gas-adsorption behaviors of the pristine antimonene are investigated by first principles calculations to exploit its potential for high-performance gas sensing. The results show that the atmospheric gas molecules (N2, CO2, O2, and H2O) presented ubiquitously in the sensing environments weakly bind to antimonene, while the polluted gas adsorbates (NH3, SO2, NO, and NO2) show stronger affinity toward antimonene with considerable adsorption energies and elevated charge transfers. Considering the susceptibility of the electronic properties of antimonene induced by the adsorbed molecules, we suggest that single-layered antimonene could be an eligible sensing material for polluted gases detection.
Autors: Rui-Shen Meng;Miao Cai;Jun-Ke Jiang;Qiu-Hua Liang;Xiang Sun;Qun Yang;Chun-Jian Tan;Xian-Ping Chen;
Appeared in: IEEE Electron Device Letters
Publication date: Jan 2017, volume: 38, issue:1, pages: 134 - 137
Publisher: IEEE
 
» Floating Random Walk-Based Capacitance Extraction for General Non-Manhattan Conductor Structures
Abstract:
The non-Manhattan conductor geometry existing in some capacitance extraction problems brings difficulty to the floating random walk (FRW) method using cubic transition domains. In this paper, techniques are proposed to enhance the FRW method for handling the structures with non-Manhattan conductors. Based on the aligned-box distances and corresponding calculating approaches, the techniques for generating the Gaussian surface and constructing axis-aligned transition cubes are proposed. A practical strategy is then proposed to judge the domination relationship of non-Manhattan conductor blocks for building the space management structure with candidate list. Finally, the strategy using rotated transition cube and related space management technique are proposed to make further acceleration. Experiments on 3-D interconnect structures including from 8 to 1000 non-Manhattan blocks show that the proposed method is from to faster than a simple extension of the original FRW method. The proposed method is also up to faster than a boundary element method-based solver. Additional experiments are carried out to further validate the accuracy and efficiency of the proposed techniques, and to demonstrate their suitability for large and multi-dielectric structures.
Autors: Zhezhao Xu;Chao Zhang;Wenjian Yu;
Appeared in: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Publication date: Jan 2017, volume: 36, issue:1, pages: 120 - 133
Publisher: IEEE
 
» Floorplanning Automation for Partial-Reconfigurable FPGAs via Feasible Placements Generation
Abstract:
When dealing with partially reconfigurable designs on field-programmable gate array, floorplanning represents a critical step that highly impacts system’s performance and reconfiguration overhead. However, current vendor design tools still require the floorplan to be manually defined by the designer. Within this paper, we provide a novel floorplanning automation framework, integrated in the Xilinx tool chain, which is based on an explicit enumeration of the possible placements of each region. Moreover, we propose a genetic algorithm (GA), enhanced with a local search strategy, to automate the floorplanning activity on the defined direct problem representation. The proposed approach has been experimentally evaluated with a synthetic benchmark suite and real case studies. We compared the designed solution against both the state-of-the-art algorithms and alternative engines based on the same direct problem representation. Experimental results demonstrated the effectiveness of the proposed direct problem representation and the superiority of the defined GA engine with respect to the other approaches in terms of exploration time and identified solution.
Autors: Marco Rabozzi;Gianluca Carlo Durelli;Antonio Miele;John Lillis;Marco Domenico Santambrogio;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Jan 2017, volume: 25, issue:1, pages: 151 - 164
Publisher: IEEE
 
» Flow Allocation for Maximum Throughput and Bounded Delay on Multiple Disjoint Paths for Random Access Wireless Multihop Networks
Abstract:
In this paper, we consider random-access wireless multihop networks, with multipacket reception capabilities, where multiple flows are forwarded to the gateways through node disjoint paths. We explore the issue of allocating flow on multiple paths, exhibiting both intra- and interpath interference, in order to maximize average aggregate flow throughput (AAT) and provide bounded packet delay. A distributed flow allocation scheme is proposed where allocation of flow on paths is formulated as an optimization problem. Through an illustrative topology, it is shown that the corresponding problem is nonconvex. Furthermore, a simple but accurate model is employed for the AAT achieved by all flows, which captures both intra- and interpath interference through the signal-to-interference-plus-noise ratio (SINR) model. The proposed scheme is evaluated through Ns2 simulations of several random wireless scenarios. Simulation results reveal that the model employed accurately captures the AAT observed in the simulated scenarios, even when the assumption of saturated queues is removed. Simulation results also show that the proposed scheme achieves significantly higher AAT for the vast majority of the wireless scenarios explored than for the following flow allocation schemes: one that assigns flows on paths on a round-robin fashion, one that optimally utilizes the best path (BP) only, and another one that assigns the maximum possible flow on each path. Finally, a variant of the proposed scheme is explored, where interference for each link is approximated by considering its dominant interfering nodes only.
Autors: Manolis Ploumidis;Nikolaos Pappas;Apostolos Traganitis;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Jan 2017, volume: 66, issue:1, pages: 720 - 733
Publisher: IEEE
 
» Flux Control Range Broadening and Torque Ripple Minimization of a Double Excitation Synchronous Motor
Abstract:
This paper presents performance improvements of a double excitation synchronous motor by using a reluctance network (RN). The distinguishing feature of the double excitation principle is to use permanent magnets with high energy, while air-gap flux is flexibly controlled by field windings. Therefore, the first contribution of this paper focuses on maximizing air-gap flux range control. Second, an approach for torque ripple reduction is proposed by directly modifying air-gap flux according to the instantaneous torque profile. The achieved resultant torque stays almost constant for a case study. The validity of the RN method is examined by comparisons with 3-D finite element and experimental results for several machines.
Autors: K. Hoang;L. Vido;M. Gabsi;F. Gillon;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jan 2017, volume: 53, issue:1, pages: 1 - 10
Publisher: IEEE
 
» Fly robotic? [Top Tech 2017]
Abstract:
In the future, the joke goes, airliners will each have a pilot and a dog. The dog will be there to bite the pilot if he touches the controls, and the pilot will be there to feed the dog.
Autors: Philip E. Ross;
Appeared in: IEEE Spectrum
Publication date: Jan 2017, volume: 54, issue:1, pages: 54 - 55
Publisher: IEEE
 
» Focus Improvement for High-Resolution Highly Squinted SAR Imaging Based on 2-D Spatial-Variant Linear and Quadratic RCMs Correction and Azimuth-Dependent Doppler Equalization
Abstract:
The results of the linear range cell migration (RCM) correction and inherent range-dependent squint angle in the case of high-resolution highly squinted synthetic aperture radar (SAR) imaging produce two-dimensional (2-D) spatial-variant RCMs and azimuth-dependent Doppler parameters (i.e., highly varying Doppler centroid and frequency modulation rates), which make highly squinted SAR imaging difficult. However, the most existing algorithms failed to consider these problems. To obtain high-quality SAR image, in this study, both the 2-D spatial-variant RCMs and the azimuth-dependent Doppler parameters are studied. First, a reference range linear RCM correction (RCMC) is used to remove the most of the linear RCM components and to mitigate the range-azimuth coupling of the 2-D spectrum. And then, in the azimuth time dimension, a new perturbation function is designed in the extended nonlinear chirp scaling (CS) (ENLCS) algorithm to overcome the azimuth-dependent RCM and to equalize Doppler parameters. To remove both the inherent range-dependent RCM and the linear RCM caused by the range-dependent squint angle, a modified CS (MCS) algorithm with a new scaling function is proposed, and for the residual RCMs, a bulk RCMC and second range compression (SRC) are utilized to compensate them. With the proposed ENLCS and MCS operation, the 2-D spatial-variant RCMC and the azimuth-dependent Doppler equalization are, thus, achieved. The experimental results with simulated data in the case of the high-resolution highly squinted SAR demonstrate the superior performance of the proposed algorithm.
Autors: Dong Li;Huan Lin;Hongqing Liu;Guisheng Liao;Xiaoheng Tan;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Jan 2017, volume: 10, issue:1, pages: 168 - 183
Publisher: IEEE
 
» Fokker—Planck Study of Parameter Dependence on Write Error Slope in Spin-Torque Switching
Abstract:
This paper analyzes write errors in spin-torque switching due to thermal fluctuations in a system with perpendicular magnetic anisotropy. Prior analytical and numerical methods are summarized; a physics-based general 2-D Fokker–Planck equation (FPE) is solved numerically. Due to its computational efficiency and broad applicability to all switching regimes and system symmetries, the 2-D FPE has been used to study the relation between write error slope and material parameters as well as some emerging switching schemes.
Autors: Yunkun Xie;Behtash Behin-Aein;Avik W. Ghosh;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Jan 2017, volume: 64, issue:1, pages: 319 - 324
Publisher: IEEE
 
» Fold-up screens could make their big debut [Top Tech 2017]
Abstract:
The rumors have been swirling for months. Though they couldn’t be confirmed, their persistence suggests that something significant may be coming from Samsung, possibly as early as this year: a foldable mobile.
Autors: Amy Nordrum;
Appeared in: IEEE Spectrum
Publication date: Jan 2017, volume: 54, issue:1, pages: 50 - 51
Publisher: IEEE
 
» Folded Substrate-Integrated Waveguide Band-Pass Post Filter
Abstract:
This letter presents a novel concept of band-pass filter realized with metal posts in folded substrate-integrated waveguide (FSIW) technology, together with an efficient specific design procedure. As a first step, it is shown that a particular dimension of the middle vane in the FSIW yields an equivalence to a dielectric-loaded unfolded rectangular waveguide. This equivalence is investigated by comparing the modal dispersion characteristics in both folded and unfolded structures. A direct comparison of the posts placed in the FSIW and in the equivalent unfolded waveguide then further confirms their similar characteristics. As a result, the classical mode-matching method (MMM), straightforwardly applied in the equivalent unfolded structure, can be used to efficiently design a post filter in FSIW technology. For illustration, the method is applied to realize a -order Chebyshev band-pass post FSIW filter with a center frequency of 7GHz and a fractional bandwidth of 5.71%. The viability and efficiency of the design approach is successfully validated by finite-element simulations and measurements.
Autors: Cheng Zhao;Christophe Fumeaux;Cheng-Chew Lim;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jan 2017, volume: 27, issue:1, pages: 22 - 24
Publisher: IEEE
 
» Four-Dimensional Imaging of Cardiac Trabeculae Contracting In Vitro Using Gated OCT
Abstract:
Cardiac trabeculae are widely used as experimental muscle preparations for studying heart muscle. However, their geometry (diameter, length, and shape) can vary not only among samples, but also within a sample, leading to inaccuracies in estimating their stress production, volumetric energy output, and/or oxygen consumption. Hence, it is desirable to have a system that can accurately image each trabecula in vitro during an experiment. To this end, we constructed an optical coherence tomography system and implemented a gated imaging procedure to image actively contracting trabeculae and reconstruct their time-varying geometry. By imaging a single cross section while monitoring the developed force, we found that gated stimulation of the muscle was sufficiently repeatable to allow us to reconstruct multiple contractions to form a four-dimensional representation of a single muscle contraction cycle. The complete muscle was imaged at various lengths and the cross-sectional area along the muscle was quantified during the contraction cycle. The variation of cross-sectional area along the length during a contraction tended to increase as the muscle was contracting, and this increase was greater at longer muscle lengths. To our knowledge, this is the first system that is able to measure the geometric change of cardiac trabeculae in vitro during a contraction, allowing cross-sectional stress and other volume-dependent parameters to be estimated with greater accuracy.
Autors: Ming L. Cheuk;Alexander J. Anderson;June-Chiew Han;Norman Lippok;Frédérique Vanholsbeeck;Bryan P. Ruddy;Denis S. Loiselle;Poul M.F. Nielsen;Andrew J. Taberner;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Jan 2017, volume: 64, issue:1, pages: 218 - 224
Publisher: IEEE
 
» Fourier Analysis of Noise Characteristics in Cone-Beam Microtomography Laboratory Scanners
Abstract:
Goal: We investigate the signal and noise performance of an x-ray microtomography system that incorporates a complementary metal–oxide–semiconductor flat-panel detector as a projection image receptor. Methods: Signal and noise performance is analyzed in the Fourier domain using modulation-transfer function (MTF), noise-power spectrum (NPS), and noise-equivalent number of quanta (NEQ) with respect to magnification and different convolution kernels for image reconstruction. Results: Higher magnification provides lower NPS, and thus, higher NEQ performance in the transaxial planes from microtomography. A window function capable of smoothing the ramp filter edge to below one-half of the Nyquist limit results in better performance in terms of NPS and NEQ. The characteristics of convolution kernels do not affect signal and noise performance in longitudinal planes; hence, MTF performance mainly dominates the NEQ performance. The signal and noise performances investigated in this study are demonstrated with images obtained from the contrast phantom and postmortem mouse. Conclusion: The results of our study could be helpful in developing x-ray microtomography systems based on flat-panel detectors.
Autors: Sun Young Jang;Ho Kyung Kim;Hanbean Youn;Seungryong Cho;Ian A. Cunningham;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Jan 2017, volume: 64, issue:1, pages: 173 - 183
Publisher: IEEE
 
» Framework for the Development of Neuroprostheses: From Basic Understanding by Sciatic and Median Nerves Models to Bionic Legs and Hands
Abstract:
Neuroprostheses based on electrical stimulation are becoming a therapeutic reality, dramatically improving the life of disabled people. They are based on neural interfaces that are designed to create an intimate contact with neural cells. These devices speak the language of electron currents, while the human nervous system uses ionic currents to communicate. A deep understanding of the complex interplay between these currents, during the electrical stimulation, is essential for the development of optimized neuroprostheses. Neural electrodes can have different geometries, placement within the nervous system, and the stimulation protocols (paradigms of use). This high-dimensional problem is not tractable by an empiric, brute-force approach and should be tackled by exact computational models, making use of our accumulated knowledge. In pursuit of this goal, a hybrid finite element method—NEURON modeling—is used for a solution of electrical field generated by stimulation, within the different neural structures having anisotropic conductivity, and a corresponding neural response computation. In this work, an important correction of perineurium electrical conductivity is computed. Models of median and sciatic nerves, innervating the hand and foot areas, relevant to the development of bionic hands and legs with sensory feedback, are implemented. The obtained results have the potential to optimize the design of neural interfaces, in terms of shape and number of stimulating contacts. Guidelines for the neurosurgical planning are proposed, by indicating the optimal number of implants for a specific nerve to obtain the best efficacy with the lowest invasiveness. The interpretation is proposed for one of the basic problems of neural interfaces, consisting in the change of the stimulation threshold due to fibrotic reaction of tissue. We show that it is possible to use human microstimulation as an experimental setup for testing of afferent s- imulation paradigms, which can be translated to further chronic implants. In the future, models will have a key role in the decision of the most appropriate design of customized neuroprostheses, their optimal modality of use, understanding the effects that occur during their use, and minimizing animal and human experimentation.
Autors: Stanisa Raspopovic;Francesco Maria Petrini;Marek Zelechowski;Giacomo Valle;
Appeared in: Proceedings of the IEEE
Publication date: Jan 2017, volume: 105, issue:1, pages: 34 - 49
Publisher: IEEE
 
» FRANK: A Fast Node Ranking Approach in Large-Scale Networks
Abstract:
To support the ever-increasing data traffic demands, the Internet has been experiencing a rapid growth in recent decades. Effective and efficient monitoring is highly needed in order to properly manage such complex infrastructure. It is of theoretical and practical significance to derive network device importance (i.e., node rank) for resource utilization optimization, user experience improvement, and security enhancement. Recent development in the Internet infrastructure has introduced prosperous in-network computation resources across the network. To exploit such distributed resources, in this article, we propose a core-graphbased framework, called FRank, for fast node ranking algorithms, which accelerates convergence and reduces communication cost by converting most inter-partition state change propagations into intra-partition ones. We have implemented FRank in a cluster to validate its correctness and efficiency. The experiment results demonstrate that at the least FRank reduces the execution time of existing cutting-edge methods by 30.2 percent with 43.5 percent less communication cost.
Autors: Yu Zhang;Lin Gu;Xiaofei Liao;Hai Jin;Deze Zeng;Bing Bing Zhou;
Appeared in: IEEE Network
Publication date: Jan 2017, volume: 31, issue:1, pages: 36 - 43
Publisher: IEEE
 
» FreeScup: A Novel Platform for Assisting Sculpture Pose Design
Abstract:
Sculpture design is challenging due to its inherent difficulty in characterizing artworks quantitatively; thus, few works have been done to assist sculpture design in the past decades in the multimedia community. We have cooperated with several sculptors on analyzing styles of different artists consisting of Giacometti, Augeuste Rodin, Henry Moore, and Marino Marini from which we find pose editing plays an important role in sculpture design. Motivated by this, we present a novel platform that allows sculptors to edit virtual three-dimensional (3-D) sculptures by a free way. The proposed platform consists of three modules, namely, sculpture initialization, sculptor-sculpture mapping, and interactive pose editing. In sculpture initialization, a virtual 3-D sculpture is first incrementally reconstructed from multiview images. Then, we define Laplace operator and its corresponding spectrum to describe the geometry information of the reconstructed sculpture. During sculptor–sculpture mapping, we apply spectral analysis on the low-frequency parts of the spectrum to search for candidate editing points on the surface of the sculpture. Next, body actions of the sculptor are captured by Kinect and further mapped onto editing points as a predefined configuration set. Finally, during interactive pose editing, a real-time Kinect-driven sculpture pose editing scheme is presented, which not only preserves geometry features of the sculpture but also allows instant changes of sculpture poses. We demonstrate that our platform successfully assists sculptors on real-time pose editing by comparing its performance with those of the existing sculpture assisting methods.
Autors: Yirui Wu;Tong Lu;Zehuan Yuan;Hao Wang;
Appeared in: IEEE Transactions on Multimedia
Publication date: Jan 2017, volume: 19, issue:1, pages: 183 - 195
Publisher: IEEE
 
» Frequency Analysis of Dopant Profiling and Capacitance Spectroscopy Using Scanning Microwave Microscopy
Abstract:
Broadband dopant profiling at gigahertz frequencies and in situ calibrated capacitance–voltage spectroscopy of silicon p–n junctions using scanning microwave microscopy (SMM) are reported. Using a 3-D finite element model to obtain the E-field distribution at the tip/sample interface, we show that the reflected signal is expected to vary monotonically with the doping concentration. imaging performed on two doped silicon samples confirms the simulation results for the full SMM operating frequency range of 1–20 GHz. In this frequency range, we compare the data with the differential data commonly used for dopant profiling. In standard SMM operating conditions, the data are monotonic over the full frequency range of 1–20 GHz, while the data show a monotonic dependence on the doping concentration between and only at lower frequencies. A nonmonotonic behavior is typically observed at higher frequencies and an interpretation based on charged carriers dynamic is given. This is important for routine and robust frequency selection workflows of for dopant profiling applications. We also show based calibrated capacitance measurements and capacitance–voltage curves of differently doped sample regions and of p–n junction interfaces.
Autors: Enrico Brinciotti;Giulio Campagnaro;Giorgio Badino;Manuel Kasper;Georg Gramse;Silviu Sorin Tuca;Juergen Smoliner;Thomas Schweinboeck;Soeren Hommel;Ferry Kienberger;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Jan 2017, volume: 16, issue:1, pages: 75 - 82
Publisher: IEEE
 
» Frequency Estimators in Sensor Networks—Bounds and Consequences
Abstract:
The Cramer–Rao lower bounds are derived for the sinusoidal signals estimation in the collaborative systems or sensor networks. Obtained expressions point to the way how to design estimator in order to achieve high accuracy. In addition, they show accuracy limits of existing approaches.
Autors: Igor Djurović;
Appeared in: IEEE Sensors Journal
Publication date: Jan 2017, volume: 17, issue:2, pages: 422 - 427
Publisher: IEEE
 
» Frequency-Adaptive Observer to Extract AC-Coupled Signals for Grid Synchronization
Abstract:
In three-phase grids, the grid synchronization has been widely discussed with mainly focusing on the mitigation of low-order harmonics and unbalances. In this paper, the elimination of a dc bias is also considered in the process of the grid synchronization. Because the proposed method is based on a frequency-adaptive observer, it can maintain its performances even if the fundamental frequency is changed. The state equation is newly established for the observer, and its gains are discussed in terms of their influences to the filtering performances. The effectiveness of the proposed method is assessed with various simulations and experiments.
Autors: Yongsoon Park;Hyeon-Sik Kim;Seung-Ki Sul;
Appeared in: IEEE Transactions on Industry Applications
Publication date: Jan 2017, volume: 53, issue:1, pages: 273 - 282
Publisher: IEEE
 
» Frequency-Channelized Mismatch-Shaped Quadrature Data Converters for Carrier Aggregation in MU-MIMO LTE-A
Abstract:
Emerging wireless standards aggregate information by selecting combinations of contiguous or non-contiguous channels, thereby enabling wider transmission bandwidths, and hence, higher data rates. Frequency-interleaved analog-to-digital conversion (FI-ADC) is an attractive emerging technique for carrier aggregation receivers because it facilitates an efficient way to dynamically vary the receiver bandwidth in order to address the many possible channel combinations. Compared to their time-interleaved counterparts, the specifications of the samplers in the parallel channels in FI-ADCs are significantly relaxed, thereby resulting in lower overall power consumption in the receiver. This work extends the FI-ADC concept to the quadrature frequency-interleaved oversampled data converter (QFI-ADC) to achieve greater aggregate data rates. Previously, digital-to-analog converter (DAC) and other inter-channel mismatches have limited the performance of QFI-ADCs. In this paper, we propose a low-complexity element rotation algorithm (ERA) to mitigate DAC mismatches. The ERA is synthesized from the corresponding mismatch transfer function using a rigorous mathematical procedure which is shown to be applicable generally to low-pass, high-pass, band-pass and quadrature ERAs. Simulations confirm that the resulting low-complexity quadrature ERAs have advantages over previously proposed approaches in both performance and hardware complexity. An additional gain calibration technique alleviates image folding due to gain and timing mismatches between the quadrature DAC elements, which yields higher SNDR.
Autors: Sandipan Kundu;Subhanshu Gupta;David J. Allstot;Jeyanandh Paramesh;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Jan 2017, volume: 64, issue:1, pages: 3 - 13
Publisher: IEEE
 
» Frequency-Varying Current Harmonics for Active Magnetic Bearing via Multiple Resonant Controllers
Abstract:
The rotating machinery suspended by an active magnetic bearing (AMB) system always suffers from rotor mass imbalance and sensor runout disturbances, which lead to the periodic fluctuations in control currents. This paper presents a novel multiple resonant controllers (MRC) for an AMB system to suppress the multifrequency current harmonics in the presence of variable rating speed. The principle and structure of the plug-in MRC used for current harmonics suppression in the AMB system is discussed. The design of the proposed MRC, using the progressively tuning and segmentation switch strategy, is given. The proposed design method for the MRC can achieve the balance between good stability and harmonics suppression precision. As well, the robustness of the overall system is systematically analyzed for the entire operational speed range. Simulation and experimental results for current fluctuations and multifrequency vibration forces on a magnetically suspended flywheel validate the effectiveness of the proposed method.
Autors: Cong Peng;Jinji Sun;Xinda Song;Jiancheng Fang;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Jan 2017, volume: 64, issue:1, pages: 517 - 526
Publisher: IEEE
 
» Fresh Ideas, Young Minds-2016 IMS Student Design Competition Winners [From the Guest Editor's Desk]
Abstract:
DIscusses the MTTS 2016 IMS Student Design competitions and reports on the research of the competition winners.
Autors: Robert Caverly;
Appeared in: IEEE Microwave Magazine
Publication date: Jan 2017, volume: 18, issue:1, pages: 7 - 7
Publisher: IEEE
 
» From the editors' desk
Abstract:
The first article in this issue is “High stress wet aging of cable dielectrics— Meeting new challenges,” by Simon Sutton, Electronics and Electrical Engineering Group, University of Southampton, UK. This review article identifies a number of gaps and contradictions in the current understanding of water treeing and highlights the inability to predict accurately future performance based on even modest changes in cable design or materials. These gaps have been identified as a consequence of the offshore windfarm industry’s desire to adopt more cost effective higher voltage cables. The article indicates a need for more focused research on the specific issues which will be faced by higher electrical stress wet design cables in a subsea environment, particularly on full scale or model cables, where the interactions of the different material layers may be important, e.g., limiting the diffusion of water or salt ions into the core. In addition, water treeing behavior at lower temperatures, more representative of the minimum temperature likely to be experienced by subsea cables, needs further investigation.
Autors: Ed Cherney;Robert Fleming;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Jan 2017, volume: 33, issue:1, pages: 5 - 6
Publisher: IEEE
 
» Front-End Isolated Quasi-Z-Source DC–DC Converter Modules in Series for High-Power Photovoltaic Systems—Part I: Configuration, Operation, and Evaluation
Abstract:
A quasi-Z-source modular cascaded converter (qZS-MCC) is proposed for dc integration of high-power photovoltaic (PV) systems. The qZS-MCC comprises series-connected front-end isolated qZS half-bridge (HB) dc–dc converter submodules (SMs). With the front-end isolation, the qZS-MCC achieves high-voltage dc capability, while maintaining modularity and PV panel grounded. The post-stage qZS-HB handles the PV voltage and power flows, dc-link voltage balance, and output-series power integration. Whereas, the front-end isolation converters of all SMs perform a constant duty cycle, lowing the control complexity. There is no double-line-frequency power flowing through the dc-side PV panels, qZS inductors, and qZS capacitors in the qZS-MCC, so small qZS impedance is possible compared to the existing qZS cascaded multilevel inverter. The configuration, operating principle, power loss evaluation, and passive components design of the proposed system are investigated in this part of the paper. The system control, modeling, and corresponding verifications are stated in Part II of this paper.
Autors: Yushan Liu;Haitham Abu-Rub;Baoming Ge;
Appeared in: IEEE Transactions on Industrial Electronics
Publication date: Jan 2017, volume: 64, issue:1, pages: 347 - 358
Publisher: IEEE
 
» FSK-Based Reactive Jammer Piggybacking
Abstract:
The complexity and sophistication of communications jamming will continue to increase over time. The traditional approach to jammer mitigation is to harden radios, often sacrificing communications performance for more advanced jamming protection. To provide an escape from this trend, we propose a jammer exploitation strategy in which the communications system causes an enemy reactive jammer to act as an unwitting relay. This can lead to an improvement in communications as a result of the jamming attack itself. The strategy proposed in this letter revolves around using a frequency-shift keying waveform that is tuned in such a way to exploit the jammer’s behavior. We derive the channel capacity when using the waveform along with practical coding, and provide numerical results to gain insight.
Autors: Marc Lichtman;T. Charles Clancy;Jeffrey H. Reed;
Appeared in: IEEE Communications Letters
Publication date: Jan 2017, volume: 21, issue:1, pages: 68 - 71
Publisher: IEEE
 
» Full-Diversity Dispersion Matrices From Algebraic Field Extensions for Differential Spatial Modulation
Abstract:
We consider differential spatial modulation (DSM) operating in a block fading environment and propose sparse unitary dispersion matrices (DMs) using algebraic field extensions. The proposed DM sets are capable of exploiting full transmit diversity and, in contrast to the existing schemes, can be constructed for systems having an arbitrary number of transmit antennas. More specifically, two schemes are proposed: 1) field-extension-based DSM (FE-DSM), where only a single conventional symbol is transmitted per space–time block; and 2) FE-DSM striking a diversity–rate tradeoff (FE-DSM-DR), where multiple symbols are transmitted in each space–time block at the cost of a reduced transmit diversity gain. Furthermore, the FE-DSM scheme is analytically shown to achieve full transmit diversity, and both proposed schemes are shown to impose decoding complexity, which is independent of the size of the signal set. It is observed from our simulation results that the proposed FE-DSM scheme suffers no performance loss compared with the existing DM-based DSM (DM-DSM) scheme, whereas FE-DSM-DR is observed to give a better bit-error-ratio performance at higher data rates than its DM-DSM counterpart. Specifically, at data rates of 2.25 and 2.75 bits per channel use, FE-DSM-DR is observed to achieve about 1- and 2-dB signal-to-noise ratio (SNR) gain with respect to its DM-DSM counterpart.
Autors: Rakshith Rajashekar;Naoki Ishikawa;Shinya Sugiura;K. V. S. Hari;Lajos Hanzo;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Jan 2017, volume: 66, issue:1, pages: 385 - 394
Publisher: IEEE
 
» Full-Diversity Uncoordinated Cooperative Transmission for Asynchronous Relay Networks
Abstract:
Due to the distributed nature of cooperative communications systems, the cooperative signals arriving at the destination may not be perfectly aligned, i.e., the system is inherently asynchronous, and signal coordination among multiple relay nodes is imperative. In this paper, we propose a distributed space–time transmission scheme for a general asynchronous cooperative relay network. The scheme provides asymptotic full cooperative diversity, even when the signals arrive at the receiver asynchronously, which can be achieved by a low-complexity minimum-mean-square-error (MMSE) decision feedback equalizer (DFE) instead of the maximum-likelihood (ML) detector. Furthermore, signal coordination is no longer required, which avoids extra coordinating overhead. The proposed scheme applies for both general amplify-and-forward (AF) and decode-and-forward (DF) cooperative communications networks, such as coordinated multipoint/networked multiple-input–multiple-output (MIMO) systems, distributed antenna systems, and relay architecture for cellular systems. Simulation results confirm our analytical results.
Autors: Hui-Ming Wang;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Jan 2017, volume: 66, issue:1, pages: 468 - 480
Publisher: IEEE
 
» Full-Duplex Meets Multiuser MIMO: Comparisons and Analysis
Abstract:
Efficient utilization of wireless communication resources and increases in the capacity of the communication networks have become very crucial claims for next-generation cellular networks. Full-duplex (FD) is a very promising technique that allows for the efficient use of wireless communication resources, given that the self-interference level can be suppressed to an acceptable level. In this paper, we consider a simple FD communication system, consisting of one FD access point (AP) and two half-duplex (HD) mobile users, and investigate when it is more advantageous for the communication network to operate in FD or HD multiuser multiple-input multiple-output (MIMO) mode. Since FD transmission is degraded by self-interference while HD suffers from spatial correlation between MIMO antennas, which causes rate loss, we study the effect of both the self-interference cancelation parameter at the FD AP and the mutual distance between the HD users on FD performances and the effect of the spatial correlation coefficient on HD MIMO. Afterward, a switching criterion is proposed, which chooses the operation mode that maximizes the downlink channel capacity while maintaining the uplink channel capacity at a certain level. Subsequently, based on our study of the system's parameters that affect the performance of both FD and HD, theoretical thresholds for these parameters are derived. Finally, numerical analysis is presented, verifying the validity of the optimization problem solution and the derived thresholds.
Autors: Radwa Sultan;Lingyang Song;Karim G. Seddik;Zhu Han;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Jan 2017, volume: 66, issue:1, pages: 455 - 467
Publisher: IEEE
 
» Full-Duplex-Based Rate/Mode Adaptation Strategies for Wi-Fi/LTE-U Coexistence: A POMDP Approach
Abstract:
The rapid increase in wireless demand prompted the FCC to open up parts of the 5-GHz band for unlicensed access. This caught the interest of 4G/LTE providers, who wish to extend their LTE-A services to the unlicensed spectrum (LTE-U). In LTE-U, small-cell base stations aggregate unlicensed and licensed bands to increase the throughput. Wi-Fi/LTE-U coexistence is a challenging issue due to the different access mechanisms of these two systems, which may cause high collision rates and delays. By leveraging self-interference-suppression techniques, we propose joint mode/rate adaptation strategies for Wi-Fi/LTE-U coexistence. Specifically, a full-duplex enabled Wi-Fi station can transmit and receive data simultaneously to increase the throughput, or transmit and sense (TS mode) simultaneously to monitor the LTE-U activity. We model the LTE-U interference as a hidden Markov process, and solve the problem of jointly adapting Wi-Fi rates/modes using a framework of partially observable Markov decision process. A detection approach based on the sliding window correlator is analyzed for the TS mode, which can differentiate between Wi-Fi and LTE-U signals. Our results indicate that our scheme provides 1.5x (1.9x) average throughput gain for Wi-Fi system in the low (high) signal-to-interference-and-noise regime relative to a half-duplex-based scheme.
Autors: Mohammed Hirzallah;Wessam Afifi;Marwan Krunz;
Appeared in: IEEE Journal on Selected Areas in Communications
Publication date: Jan 2017, volume: 35, issue:1, pages: 20 - 29
Publisher: IEEE
 
» Fully Depleted Pinned Photodiode CMOS Image Sensor With Reverse Substrate Bias
Abstract:
A new pixel design using fully depleted pinned photodiode (PPD) in a 180-nm CMOS image sensor (CIS) process has been developed and the first experimental results from a test chip are presented. The sensor can be fully depleted by means of reverse bias applied to the substrate, and the principle of operation is applicable to very thick sensitive volumes. Additional n-type implants under the in-pixel p-wells have been added to the manufacturing process in order to eliminate the large parasitic substrate current that would otherwise be present in a normal device. The new design shows the same electro-optical performance as the PPD pixel it is based on, and can be fully depleted without significant leakage currents. This development has the potential to greatly increase the quantum efficiency of scientific PPD CIS at near-infrared and soft X-ray wavelengths.
Autors: Konstantin D. Stefanov;Andrew S. Clarke;Andrew D. Holland;
Appeared in: IEEE Electron Device Letters
Publication date: Jan 2017, volume: 38, issue:1, pages: 64 - 66
Publisher: IEEE
 
» Fully Integrated Class-J Power Amplifier in Standard CMOS Technology
Abstract:
This letter discusses the integration of Class-J power amplifiers (PA). A set of modified design equations considering harmonic losses is derived and the inductor losses are discussed. Based on the discussion, a fully integrated Class-J PA with stacked-FET structure is designed and implemented in a CMOS process. The proposed Class-J PA, powered by a 3.3 V supply, achieves a power-added efficiency (PAE) and drain efficiency (DE) of 43.7% and 45.1%, respectively, with a saturated output power of 22 dBm. Along with a maximum gain of 17.4 dB, the broadband PA exhibits a 3-dB band from 2.1 GHz to 4.8 GHz.
Autors: Yezi Dong;Luhong Mao;Sheng Xie;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jan 2017, volume: 27, issue:1, pages: 64 - 66
Publisher: IEEE
 
» Fully Scalable Methods for Distributed Tensor Factorization
Abstract:
Given a high-order large-scale tensor, how can we decompose it into latent factors? Can we process it on commodity computers with limited memory? These questions are closely related to recommender systems, which have modeled rating data not as a matrix but as a tensor to utilize contextual information such as time and location. This increase in the order requires tensor factorization methods scalable with both the order and size of a tensor. In this paper, we propose two distributed tensor factorization methods, CDTF and SALS. Both methods are scalable with all aspects of data and show a trade-off between convergence speed and memory requirements. CDTF, based on coordinate descent, updates one parameter at a time, while SALS generalizes on the number of parameters updated at a time. In our experiments, only our methods factorized a five-order tensor with 1 billion observable entries, 10 M mode length, and 1 K rank, while all other state-of-the-art methods failed. Moreover, our methods required several orders of magnitude less memory than their competitors. We implemented our methods on MapReduce with two widely-applicable optimization techniques: local disk caching and greedy row assignment. They speeded up our methods up to 98.2 and also the competitors up to 5.9 .
Autors: Kijung Shin;Lee Sael;U. Kang;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Jan 2017, volume: 29, issue:1, pages: 100 - 113
Publisher: IEEE
 
» Fundamental Limits of Parallel Optical Wireless Channels: Capacity Results and Outage Formulation
Abstract:
Multi-channel (MC) optical wireless communication (OWC) systems employing wave-division multiplexing for outdoors free-space optical communications, or multi-user time-division multiple access for indoors visible-light communications, e.g., can be modeled as parallel channels. Multi-input multi-output OWC systems can also be transformed, possibly with some performance loss, to parallel channels using pre-/post-coding. Studying the performance of such MC-OWC systems requires characterizing the capacity of the underlying parallel channels. In this paper, upper and lower bounds on the capacity of constant parallel OWC channels with a total average intensity constraint are derived. Then, this paper focuses on finding intensity allocations that maximize the lower bounds given channel-state information at the transmitter (CSIT). Due to its nonconvexity, the Karush–Kuhn–Tucker conditions are used to describe a list of candidate allocations. Instead searching exhaustively for the best solution, low-complexity near-optimal algorithms are proposed. The resulting optimized lower bound nearly coincides with capacity at high signal-to-noise ratio (SNR). Under a quasi-static channel model and in the absence of CSIT, outage probability upper and lower bounds are derived. Those bounds also meet at high SNR, thus characterizing the outage capacity in this regime. Finally, the results are extended to a system with both average and peak intensity constraints.
Autors: Anas Chaaban;Zouheir Rezki;Mohamed-Slim Alouini;
Appeared in: IEEE Transactions on Communications
Publication date: Jan 2017, volume: 65, issue:1, pages: 296 - 311
Publisher: IEEE
 
» Fusing Multiple Neuroimaging Modalities to Assess Group Differences in Perception–Action Coupling
Abstract:
In the last few decades, noninvasive neuroimaging has revealed macroscale brain dynamics that underlie perception, cognition, and action. Advances in noninvasive neuroimaging target two capabilities: 1) increased spatial and temporal resolution of measured neural activity; and 2) innovative methodologies to extract brain–behavior relationships from evolving neuroimaging technology. We target the second. Our novel methodology integrated three neuroimaging methodologies and elucidated expertise-dependent differences in functional (fused EEG-fMRI) and structural (dMRI) brain networks for a perception–action coupling task. A set of baseball players and controls performed a Go/No-Go task designed to mimic the situation of hitting a baseball. In the functional analysis, our novel fusion methodology identifies 50-ms windows with predictive EEG neural correlates of expertise and fuses these temporal windows with fMRI activity in a whole-brain 2-mm voxel analysis, revealing time-localized correlations of expertise at a spatial scale of millimeters. The spatiotemporal cascade of brain activity reflecting expertise differences begins as early as 200 ms after the pitch starts and lasts up to 700 ms afterwards. Network differences are spatially localized to include motor and visual processing areas, providing evidence for differences in perception–action coupling between the groups. Furthermore, an analysis of structural connectivity reveals that the players have significantly more connections between cerebellar and left frontal/motor regions, and many of the functional activation differences between the groups are located within structurally defined network modules that differentiate expertise. In short, our novel method illustrates how multimodal neuroimaging can provide specific macroscale insights into the functional and structural correlates of expertise development.
Autors: Jordan Muraskin;Jason Sherwin;Gregory Lieberman;Javier O. Garcia;Timothy Verstynen;Jean M. Vettel;Paul Sajda;
Appeared in: Proceedings of the IEEE
Publication date: Jan 2017, volume: 105, issue:1, pages: 83 - 100
Publisher: IEEE
 
» Fusion of Sun-Synchronous and Geostationary Images for Coastal and Ocean Color Survey Application to OLCI (Sentinel-3) and FCI (MTG)
Abstract:
Open ocean and coastal area monitoring requires multispectral satellite images with a middle spatial resolution and a high temporal repeatability . As no current satellite sensors have such features, the aim of this study is to propose a fusion method to merge images delivered by a low earth orbit (LEO) sensor with images delivered by a geostationary earth orbit (GEO) sensor. This fusion method, called spatial spectral temporal fusion (SSTF), is applied to the future sensors—Ocean and Land Color Instrument (OLCI) (on Sentinel-3) and Flexible Combined Imager (FCI) (on Meteosat Third Generation) whose images were simulated. The OLCI bands, acquired at t0, are divided by the oversampled corresponding FCI band acquired at t0 and multiplied by the FCI bands acquired at t1. The fusion product is used for the next fusion at t1 and so on. The high temporal resolution of FCI allows its signal-to-noise ratio (SNR) to be enhanced by the means of temporal filtering. The fusion quality indicator ERGAS computed between SSTF fusion products and reference images is around 0.75, once the FCI images are filtered from the noise and 1.08 before filtering. We also compared the estimation of chlorophyll (Chl), suspended particulate matter (SPM), and colored dissolved organic matter (CDOM) maps from the fusion products with the input simulation maps. The comparison shows an average relative errors on Chl, SPM, and CDOM, respectively, of 64.6%, 6.2%, and 9.5% with the SSTF method. The SSTF method was also compared with an existing fusion method called the spati l and temporal adaptive reflectance fusion model (STARFM).
Autors: Cécile Peschoud;Audrey Minghelli;Sandrine Mathieu;Manchun Lei;Ivane Pairaud;Christel Pinazo;
Appeared in: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication date: Jan 2017, volume: 10, issue:1, pages: 45 - 56
Publisher: IEEE
 
» Gait Rhythm Fluctuation Analysis for Neurodegenerative Diseases by Empirical Mode Decomposition
Abstract:
Previous studies have indicated that gait rhythm fluctuations are useful for characterizing certain pathologies of neurodegenerative diseases such as Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), and Parkinson's disease (PD). However, no previous study has investigated the properties of frequency range distributions of gait rhythms. Therefore, in our study, empirical mode decomposition was implemented for decomposing the time series of gait rhythms into intrinsic mode functions from the high-frequency component to the low-frequency component sequentially. Then, Kendall's coefficient of concordance and the ratio for energy change for different IMFs were calculated, which were denoted as W and , respectively. Results revealed that the frequency distributions of gait rhythms in patients with neurodegenerative diseases are less homogeneous than healthy subjects, and the gait rhythms of the patients contain much more high-frequency components. In addition, parameters of W and can significantly differentiate among the four groups of subjects (HD, ALS, PD, and healthy subjects) (with the minimum p-value of 0.0000493). Finally, five representative classifiers were utilized in order to evaluate the possible capabilities of W and to distinguish the patients with neurodegenerative diseases from the healthy subjects. This achieved maximum area under the curve values of 0.949, 0.900, and 0.934 for PD, HD, and ALS detection, respectively. In sum, our study suggests that gait rhythm features extracted in the frequency domain should be given consideration seriously in the future neurodegenerative disease cha acterization and intervention.
Autors: Peng Ren;Shanjiang Tang;Fang Fang;Lizhu Luo;Lei Xu;Maria L. Bringas-Vega;Dezhong Yao;Keith M. Kendrick;Pedro A. Valdes-Sosa;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Jan 2017, volume: 64, issue:1, pages: 52 - 60
Publisher: IEEE
 
» Game User-Oriented Multimedia Transmission Over Cognitive Radio Networks
Abstract:
Cognitive radio (CR) is an emerging technique to improve the efficiency of spectrum resource utilization. In CR networks, the selfish behavior of secondary users (SUs) can considerably affect the performance of primary users (PUs). Accordingly, game theory, which considers the game players’ selfish behavior, has been applied to the design of CR networks. Most of the existing studies focus on the network design only from the network perspective to improve system performance, such as utility and throughput. However, the users’ experience to the service, which cannot simply be reflected by quality of service, has been largely ignored. The user-perceived multimedia quality and service can be different from the actual received multimedia quality, and thus is very important to consider the network design. To better serve the network users, quality of experience (QoE) is adopted to measure the network service from the users’ perspective and help improve the users’ satisfaction to the CR network service. As CR networks require a lot of data storage and computation for spectrum sensing, spectrum sharing, and algorithm design, cloud computation comes as a convenient solution, because it can provide massive storage and fast computation. In this paper, we propose to design a user-oriented CR cloud network for multimedia applications, where the user’s satisfaction is reflected in the CR cloud network design. In the proposed framework, the PU and SU game is formulated as Stackelberg game. In particular, a refunding term is defined in the users’ utility function to effectively consider and to reflect the network users’ QoE requirement. Our contributions are twofold: 1) a game-based CR cloud network design for multimedia transmission is proposed, and the network user’s QoE requirement is satisfied in the design and 2) the existence- and the uniqueness of the Stackelberg Nash equilibrium are proved, and the design is optimal. Our simulation results demonstrate the effectiveness of the game user-oriented CR cloud network design.
Autors: Jingfang Huang;Honggang Wang;Yi Qian;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Jan 2017, volume: 27, issue:1, pages: 198 - 208
Publisher: IEEE
 
» Gaussian States Minimize the Output Entropy of the One-Mode Quantum Attenuator
Abstract:
We prove that Gaussian thermal input states minimize the output von Neumann entropy of the one-mode Gaussian quantum-limited attenuator for fixed input entropy. The Gaussian quantum-limited attenuator models the attenuation of an electromagnetic signal in the quantum regime. The Shannon entropy of an attenuated real-valued classical signal is a simple function of the entropy of the original signal. A striking consequence of energy quantization is that the output von Neumann entropy of the quantum-limited attenuator is no more a function of the input entropy alone. The proof starts from the majorization result of De Palma et al., IEEE Trans. Inf. Theory 62, 2895 (2016), and is based on a new isoperimetric inequality. Our result implies that geometric input probability distributions minimize the output Shannon entropy of the thinning for fixed input entropy. Moreover, our result opens the way to the multimode generalization that permits to determine both the triple trade-off region of the Gaussian quantum-limited attenuator and the classical capacity region of the Gaussian degraded quantum broadcast channel.
Autors: Giacomo De Palma;Dario Trevisan;Vittorio Giovannetti;
Appeared in: IEEE Transactions on Information Theory
Publication date: Jan 2017, volume: 63, issue:1, pages: 728 - 737
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