Electrical and Electronics Engineering publications abstract of: 01-2018 sorted by title, page: 5

» Dependability Assessment of SOA-Based CPS With Contracts and Model-Based Fault Injection
Abstract:
Engineering complex distributed systems is challenging. Recent solutions for the development of cyber-physical systems (CPS) in industry tend to rely on architectural designs based on service orientation, where the constituent components are deployed according to their service behavior and are to be understood as loosely coupled and mostly independent. In this paper, we develop a workflow that combines contract-based and CPS model-based specifications with service orientation, and analyze the resulting model using fault injection to assess the dependability of the systems. Compositionality principles based on the contract specification help us to make the analysis practical. The presented techniques are evaluated on two case studies.
Autors: Loris Dal Lago;Orlando Ferrante;Roberto Passerone;Alberto Ferrari;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Jan 2018, volume: 14, issue:1, pages: 360 - 369
Publisher: IEEE
 
» Deploying Software Team Analytics in a Multinational Organization
Abstract:
Implementing a software engineering analytics solution poses challenges and offers significant value for the globally distributed software development organization at ABB. Because software development activities in agile methodologies revolve around the team, ABB decided to implement an analytics solution focused on team metrics as part of its Software Development Improvement Program. Using key indicators focused around team improvement, researchers found that teams could manage their activities with metrics such as cycle time. Key lessons learned include paying attention to visual design and navigation and providing drill-down capabilities for the user. This article is part of a special issue on Actionable Analytics for Software Engineering.
Autors: Vinay Augustine;John Hudepohl;Przemyslaw Marcinczak;Will Snipes;
Appeared in: IEEE Software
Publication date: Jan 2018, volume: 35, issue:1, pages: 72 - 76
Publisher: IEEE
 
» Derivative-Free Kalman Filtering Based Approaches to Dynamic State Estimation for Power Systems With Unknown Inputs
Abstract:
This paper proposes a decentralized derivative-free dynamic state estimation method in the context of a power system with unknown inputs, to address cases when system linearization is cumbersome or impossible. The suggested algorithm tackles situations when several inputs, such as the excitation voltage, are characterized by uncertainty in terms of their status. The technique engages one generation unit only and its associated measurements, and it remains totally independent of other system wide measurements and parameters, facilitating in this way the applicability of this process on a decentralized basis. The robustness of the method is validated against different contingencies. The impact of parameter errors, process, and measurement noise on the unknown input estimation performance is discussed. This understanding is further supported through detailed studies in a realistic power system model.
Autors: Georgios Anagnostou;Bikash C. Pal;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2018, volume: 33, issue:1, pages: 116 - 130
Publisher: IEEE
 
» Design and Analysis of Energy-Efficient Single-Pulse Piezoelectric Energy Harvester and Power Management IC for Battery-Free Wireless Remote Switch Applications
Abstract:
This paper presents a piezoelectric-based power management solution for battery-free wireless remote switches (BWSs). The proposed BWS IC, including a piezoelectric (PE) energy harvester and a buck converter, can collect the energy generated by a single PE-button press, and then supply that energy to a wireless transmitter to send a message. By combining a rectifier using the synchronized switch harvesting on inductor technique and a 6:1 series–parallel switched-capacitor converter, the proposed PE energy harvester can maximize the collected amount of energy, while supplying it at a low output voltage. In addition, by employing a switching-based start-up scheme and a variable ON-time pulse-frequency modulation scheme, the proposed buck converter can reduce the loss associated with charging the output capacitor during start-up, and then deliver the largest possible energy to the load, while maintaining low voltage ripples and high-power efficiency. A prototype BWS IC fabricated with high-voltage 250-nm CMOS technology was shown to be capable of harvesting a total energy of from a single button-pressing of a 300-mm2 lead magnesium niobate-lead titanate PE disc. More than was delivered to the load, sufficient to transmit a 4-B-long message via a 2.4-GHz wireless USB channel over a 10-m distance.
Autors: Minbok Lee;Joonseok Yang;Myeong-Jae Park;Sung-Youb Jung;Jaeha Kim;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Jan 2018, volume: 65, issue:1, pages: 366 - 379
Publisher: IEEE
 
» Design and Analysis of FTZNN Applied to the Real-Time Solution of a Nonstationary Lyapunov Equation and Tracking Control of a Wheeled Mobile Manipulator
Abstract:
The Lyapunov equation is widely employed in the engineering field to analyze stability of dynamic systems. In this paper, based on a new evolution formula, a novel finite-time recurrent neural network (termed finite-time Zhang neural network, FTZNN) is proposed and studied for solving a nonstationary Lyapunov equation. In comparison with the original Zhang neural network (ZNN) model for a nonstationary Lyapunov equation, the convergence performance has a remarkable improvement for the proposed FTZNN model and can be accelerated to finite time. Besides, by solving the differential inequality, the time upper bound of the FTZNN model is computed theoretically and analytically. Simulations are conducted and compared to validate the superiority of the FTZNN model to the original ZNN model for solving the nonstationary Lyapunov equation. At last, the FTZNN model is successfully applied to online tracking control of a wheeled mobile manipulator.
Autors: Lin Xiao;Bolin Liao;Shuai Li;Zhijun Zhang;Lei Ding;Long Jin;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Jan 2018, volume: 14, issue:1, pages: 98 - 105
Publisher: IEEE
 
» Design and Analysis of W-Band Injection-Locked Frequency Divider Using Split Transformer-Coupled Oscillator Technique
Abstract:
A W-band injection-locked frequency divider (ILFD) with low-power and wide locking range is presented in this paper. The operation frequency and locking range are enhanced by using split transformer-coupled oscillator. The optimum bias and the size of the injection transistor are chosen to achieve wider locking range without increasing chip area and dc power consumption. The proposed ILFD is implemented in 90-nm CMOS and exhibits 25.4% locking range from 75.1 to 99 GHz at an input power of 0 dBm without any tuning mechanism. The core dc power consumption is 2.45 mW with a supply voltage of 0.7 V and the core chip size is mm2.
Autors: Yu-Hsuan Lin;Huei Wang;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2018, volume: 66, issue:1, pages: 177 - 186
Publisher: IEEE
 
» Design and Dynamic Characterization of an Orientation Insensitive Microwave Water-Cut Sensor
Abstract:
Modern reservoir management in oil and gas industry relies on accurate water fraction measurement which is produced as a by-product with oil. This paper presents a novel and contactless water fraction (also known as water-cut) measurement technique which is independent of geometric distribution of oil and water inside the pipe. The sensor is based on a modified T-resonator implemented directly on the pipe’s outer surface and whose resonance frequency decreases by increasing the water content in oil. The E-fields have been made to rotate and distribute well inside the pipe, despite having narrow and curved ground plane. It makes the sensor’s reading dependent only on the water fraction and not on the mixture distribution inside the pipe. That is why, the presented design does not require any flow conditioner to homogenize the oil/water mixture unlike many commercial water-cut (WC) sensors. The presented sensor has been realized by using extremely low-cost methods of screen printing and reusable 3-D printed mask. Complete characterization of the proposed WC sensor, both in horizontal and vertical orientations, has been carried out in an industrial flow loop. Excellent repeatability of the sensor’s response has been observed in “dispersed bubble” as well as in “stratified wavy” flow regimes. The performance test of the sensor confirms that the water fraction measurement is independent of the flow pattern, flow rate or orientation. The measured performance results of the sensor show full range accuracy of ±2%–3% while tested under random orientations and wide range of flow rates.
Autors: Muhammad Akram Karimi;Muhammad Arsalan;Atif Shamim;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2018, volume: 66, issue:1, pages: 530 - 539
Publisher: IEEE
 
» Design and Multiplierless Realization of Maximally Flat Sharpened-CIC Compensators
Abstract:
Polynomial sharpening is an efficient technique for improving folding band response of cascaded-integrator-comb (CIC) decimation filters. However, the sharpening of folding bands results in a high passband droop, which is intolerable in many applications. The droop can be reduced by connecting a symmetric finite-impulse-response filter called compensator in the cascade with the sharpened CIC (SCIC) filter. This brief presents a method for the design of such compensators, which is based on maximally flat error criterion. The compensator’s coefficients are obtained by solving a linear system of equations which is formed using a straightforward procedure. The coefficients obtained generally take real values. However, we show that for the SCIC filters incorporating integer or sum of powers of two (SPT) polynomial coefficients, and whose decimation factors are expressed as powers of two, the coefficients of corresponding maximally flat compensators are integers or SPT representable. For these types of SCIC filters, the optimum multiplierless structures of the compensators with three and five coefficients are described.
Autors: Goran Molnar;Aljosa Dudarin;Mladen Vucic;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Jan 2018, volume: 65, issue:1, pages: 51 - 55
Publisher: IEEE
 
» Design and Optimization of SIW Center-Fed Series Rectangular Dielectric Resonator Antenna Array With 45° Linear Polarization
Abstract:
The modeling, design, and optimization of a new substrate integrated waveguide middle-fed series rectangular dielectric resonator antenna array with 45° linear polarization are presented. The implicit space mapping technique is applied for the optimization of the antenna array. A tunable circuit model is built, which serves as the coarse/surrogate mode, and a full-wave solver is used as the fine model. High design and optimization efficiency is demonstrated using an eight-element array. The reflection coefficient of the array antenna is optimized with only two iterations. The experimental data for the eight elements antenna array, operating at the millimeter-wave band (34–36 GHz), are used for the validation of both performance of the design and modeling techniques. The measured radiation pattern demonstrates a broadside beam with a maximum radiated gain of 13.55 dB over an operating impedance bandwidth of 2.2 GHz.
Autors: Mona S. Abdallah;Ying Wang;Wael M. Abdel-Wahab;Safieddin Safavi-Naeini;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jan 2018, volume: 66, issue:1, pages: 23 - 31
Publisher: IEEE
 
» Design and Simulations of Ge2Sb2Te5 Vertical Photodetector for Silicon Photonic Platform
Abstract:
Here, we report design and simulations of a vertical photodetector based on amorphous Ge2Sb2Te5 (-GST) for silicon platform at telecommunication wavelength (1550 nm). In our investigations, it is found that -GST on silicon platform can be used as a waveguide photodetector with good responsivity and low dark current. Optimization of the structure is done to improve absorption, photocurrent, and corresponding electrical current at cathode. Our investigations reveal that ~150 nm is optimized thickness of -GST material for high responsivity (~48 A/W) when integrated on top of a single-mode silicon-on-insulator waveguide. This responsivity is comparable with existing avalanche photodiodes. With optimized dimensions, a good ratio of photocurrent to dark current is obtained. To the best of our knowledge, this is the first report on -GST-based photodetector.
Autors: Vibhu Srivastava;Manoj Tolani; Sunny;Rajesh Kumar;
Appeared in: IEEE Sensors Journal
Publication date: Jan 2018, volume: 18, issue:2, pages: 540 - 546
Publisher: IEEE
 
» Design and Testing of Novel Airborne Atmospheric Sensor Nodes
Abstract:
The design and test results are presented for a novel in situ atmospheric probe, called an environmental mote or eMote. This lightweight airborne atmospheric sensing mote has been designed for mass deployment over weather events of interest as part of a system known as GlobalSense, which aims to provide weather data with high spatial and temporal density. This letter describes the initial eMote design and ground-based test results of meteorological sensing functions. Future work to improve upon the system and move toward large-scale testing is outlined.
Autors: Michael Bolt;J. Craig Prather;Haley Harrell;Tyler Horton;John Manobianco;Mark L. Adams;
Appeared in: IEEE Geoscience and Remote Sensing Letters
Publication date: Jan 2018, volume: 15, issue:1, pages: 73 - 77
Publisher: IEEE
 
» Design of a Dual-Mode Balun Bandpass Filter With High Selectivity
Abstract:
In this letter, a new dual-mode balun bandpass filter (BPF) with high selectivity is proposed. The balun BPF is mainly composed of two different types of microstrip-to-slotline transition structures, two identical dual-mode stub-loaded resonators, and a pair of balanced outputs. First, to convert unbalanced signals from port 1 into balanced signals between port 2 and port 3, two different types of microstrip-to-slotline transition structures are utilized. Afterward, two identical stub-loaded resonators are embedded in the circuit for realizing the dual-mode bandpass response. Furthermore, four transmission zeros generated outside the passband are wisely introduced and well elucidated, thus ensuring high selectivity performance. For demonstration, a sample of balun BPF centered at 2.78 GHz ( with 0.5-dB magnitude imbalance and 5° phase imbalance is designed, fabricated, and measured. Both simulation and measurement are in good agreements.
Autors: Haiyan Xu;Jianpeng Wang;Lei Zhu;Feng Huang;Wen Wu;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jan 2018, volume: 28, issue:1, pages: 22 - 24
Publisher: IEEE
 
» Design of a High Extinction Ratio Tunable Graphene on White Graphene Polarizer
Abstract:
A thermally/electrically tunable graphene on white graphene polarizer is proposed, in which the resonant coupling between the plasmonic surface modes of the structure and the transverse electric (TE) [or transverse magnetic (TM)] polarized incident wave is used to absorb this polarization, while the TM (or TE) polarized incident wave is totally reflected. It is then shown that the thermal and electrical tunability of surface conductivity of graphene can be used to control the optical properties of the proposed polarizer, including the selection of the desired polarization, and adjusting the amplitude of the reflected (desired) polarization. The application of the hexagonal boron-nitride (white graphene) as the substrate of graphene increases the propagation of the surface waves of the structure, which in turn results in the very high polarization extinction ratio of 75 dB. Moreover, the ultra-small insertion loss of 0.022 dB and relatively large bandwidth of ~ 60 nm are calculated for the proposed polarizer.
Autors: Ali Farmani;Mehdi Miri;Mohammad Hossein Sheikhi;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2018, volume: 30, issue:2, pages: 153 - 156
Publisher: IEEE
 
» Design of a Vivaldi-Fed Hybrid Horn Antenna for Low-Frequency Gain Enhancement
Abstract:
This communication proposes the hybrid Vivaldi-fed horn antenna, which consists of the printed antipodal Vivaldi antenna (AVA) on an FR4 substrate for better matching performance in the low-frequency band and the horn antenna that surrounds the exterior of the AVA for increased gain performance in the high frequency. In order to verify the operating principle in the low-frequency band, an equivalent circuit of the proposed antenna is modeled and analyzed. The mode decomposition technique is then used to examine the radiation physics of the proposed antenna in high-frequency band. The measured reflection coefficients in the entire frequency range are less than −3 dB of the half-power reference (maximum of −4.11 dB). The measured gains of 2.12 dBi at 1 GHz and 7.84 dBi at 6 GHz are obtained. These results confirm that the better characteristics in low-frequency matching and high-frequency gain can be achieved by the proposed design.
Autors: Tae Heung Lim;Jong-Eon Park;Hosung Choo;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jan 2018, volume: 66, issue:1, pages: 438 - 443
Publisher: IEEE
 
» Design of Application-Specific Architectures for Networked Labs-on-Chips
Abstract:
Labs-on-Chips (LoCs) implement laboratory procedures on a single chip and are successfully used for chemical and biomedical applications. A promising and emerging realization of such chips are Networked LoCs (NLoCs) in which small volumes of fluids, so-called droplets, flow in closed channels of submillimeter diameters. NLoCs allow for an incubation and storage of assays over a long period of time and, hence, avoid evaporation and unwanted reactions. To increase the flexibility, effectiveness, and reusability, network functionalities allow to passively route droplets in channels and, hence, to dynamically select operations depending on the executed experiment. However, only manually designed architectures are considered for NLoCs thus far. They frequently suffer from large execution times and/or a high contamination of channels. To overcome these drawbacks, we propose the consideration of application-specific architectures for NLoCs. To this end, an automatic design method is proposed which, for a given set of experiments as well as constraints and objectives from the designer, is able to generate an optimized NLoC architecture realizing these experiments. Evaluations and case studies demonstrate the potential of the proposed solution for design exploration. Moreover, we are able to show that application-specific architectures are capable of realizing experiments in just a fraction of the time needed by architectures used thus far as well as with a substantially reduced contamination.
Autors: Andreas Grimmer;Werner Haselmayr;Andreas Springer;Robert Wille;
Appeared in: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Publication date: Jan 2018, volume: 37, issue:1, pages: 193 - 202
Publisher: IEEE
 
» Design of Dual-Loaded RFID Tag for Higher Order Modulations
Abstract:
A touchstone for selecting two scattering states for scalar differential backscattering in passive scatterers was introduced by Green in 1963. According to this model, a scatterer has one global minimum and one global maximum scattering states on its plane. The variation of radar cross section (RCS) of the scatterer between these two states is monotonic. Thus, to achieve to the highest differential backscattering the scatterer should switch between these two states. In this paper, we verify, by measurements and simulations, that a linear half-wave dipole antenna behaves as predicted by the Green model. However, we show that the RCS of a T-match bow tie antenna over its plane cannot be modeled by the Green model and instead the antenna has two maximum scattering states on its plane. In the next step, we use dual loading on the T-match bowtie antenna structure. By appropriate selection of the loads, the antenna can provide various scattering states with various magnitudes in 360° phase span in its in-phase and quadrature plane. This feature of the proposed antenna can be used to increase the modulation depth up to 170%, provide a quasi-32-quasi-quadrature amplitude shift keying, and increase the coverage range in backscattering links.
Autors: Shadi Ebrahimi-Asl;Mohammad Tayeb Ghasr;Maciej J. Zawodniok;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2018, volume: 66, issue:1, pages: 410 - 419
Publisher: IEEE
 
» Design of Five-Way Bagley Polygon Power Dividers in Rectangular Waveguide
Abstract:
Power combiners are in general complex to manufacture and do not show a compact structure when more than two output ports are needed. To overcome these problems, the design of a five-way Bagley polygon in rectangular waveguide is presented. The proposed geometry is simple, suitable for an efficient optimization, and allows its fabrication by milling. A five-way Ku-band -plane rectangular waveguide Bagley polygon for a 17% fractional bandwidth is designed, manufactured, and measured. The measured results show return loss better than 28 dB and amplitude and phase imbalances below ±0.2 dB and ±5°, respectively, which, along with the waveguide low losses, leads to a 98% efficiency as power combiner.
Autors: Ana Buesa-Zubiria;Jaime Esteban;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2018, volume: 66, issue:1, pages: 116 - 127
Publisher: IEEE
 
» Design of GaN-Based Multicolor Tunnel-Junction Light-Emitting Diodes
Abstract:
The design of monolithic multicolor tunnel-junction (TJ) light-emitting diodes (LEDs) are investigated numerically. This paper primarily aims to design and study monolithic TJ LED devices that possess high luminous efficiency and wide color gamut using a simple fabrication process. First, the characteristics of green and blue single LEDs are explored. Nonuniform carrier distribution inside quantum wells (QWs), which is due to the deep QWs and severe polarization effect, is observed for both single LEDs under study. Based on structural analysis of the single LEDs, streamline dual-color and broadband TJ LED structures, in which the blue unit LED has two pairs of 3-nm-thick QWs and the green unit LED has 3-nm-thick single QW, are designed and investigated. Specifically, monolithic dual-color blue/green (459/530 nm) TJ LED is proposed and analyzed using effective n+-GaN/i-In0.2 Ga0.8N/p+-GaN TJ. Furthermore, broadband TJ LED with simulated full width at half maximum of around 100 nm is achieved.
Autors: Ya-Hsuan Shih;Jih-Yuan Chang;Yen-Kuang Kuo;Fang-Ming Chen;Man-Fang Huang;Ming-Lun Lee;Jinn-Kong Sheu;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Jan 2018, volume: 65, issue:1, pages: 165 - 171
Publisher: IEEE
 
» Design of Low-Power Low-Area Tunable Active RC Filters
Abstract:
A method to design low-power low-area active RC filters is presented. The output voltages of the operational amplifiers are scaled and buffered, allowing the use of single stage topologies for less power consumption and eliminating the compensation capacitor. Tuning of the filter characteristic is also done by switching the currents through the output buffers, which removes the need for capacitor banks. The advantages of the proposed method are incorporated to present a general low-power biquad with small die area. The biquad section is then used to design a low-power baseband filter for Bluetooth receivers with 600-KHz cutoff frequency. The fourth-order filter, fabricated in a 0.18- CMOS process, consumes 0.5 mW with a die area of 0.13 mm.
Autors: Amirhossein Rasekh;M. Sharif Bakhtiar;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Jan 2018, volume: 65, issue:1, pages: 6 - 10
Publisher: IEEE
 
» Design of Scalable Hardware-Efficient Compressive Sensing Image Sensors
Abstract:
This paper presents a new compressive sensing (CS) measurement method for image sensors, which limits pixel summation within neighbor pixels and follows regular summation patterns. Simulations with a large set of benchmark images show that the proposed method leads to improved image quality. Circuit implementation for the proposed CS measurement method is presented with the use of current mode pixel cells; and the resultant CS image sensor circuit is significantly simpler than existing designs. With compression rates of 4 and 8, the developed CS image sensors can achieve 34.2- and 29.6-dB PSNR values with energy consumption of 1.4 and 0.73 per frame, respectively.
Autors: Stefan Leitner;Haibo Wang;Spyros Tragoudas;
Appeared in: IEEE Sensors Journal
Publication date: Jan 2018, volume: 18, issue:2, pages: 641 - 651
Publisher: IEEE
 
» Design of Sparse Halbach Magnet Arrays for Portable MRI Using a Genetic Algorithm
Abstract:
Permanent magnet arrays offer several attributes attractive for the development of a low-cost portable MRI scanner for brain imaging. They offer the potential for a relatively lightweight, low to mid-field system with no cryogenics, a small fringe field, and no electrical power requirements or heat dissipation needs. The cylindrical Halbach array, however, requires external shimming or mechanical adjustments to produce B0 fields with standard MRI homogeneity levels (e.g., 0.1 ppm over field of view), particularly when constrained or truncated geometries are needed, such as a head-only magnet where the magnet length is constrained by the shoulders. For portable scanners using rotation of the magnet for spatial encoding with generalized projections, the spatial pattern of the field is important since it acts as the encoding field. In either a static or rotating magnet, it will be important to be able to optimize the field pattern of cylindrical Halbach arrays in a way that retains construction simplicity. To achieve this, we present a method for designing an optimized cylindrical Halbach magnet using the genetic algorithm (GA) to achieve either homogeneity (for standard MRI applications) or a favorable spatial encoding field pattern (for rotational spatial encoding applications). We compare the chosen designs against a standard, fully populated sparse Halbach design, and evaluate optimized spatial encoding fields using point-spread-function and image simulations. We validate the calculations by comparing to the measured field of a constructed magnet. The experimentally implemented design produced fields in good agreement with the predicted fields, and the GA was successful in improving the chosen metrics. For the uniform target field, an order of magnitude homogeneity improvement was achieved compared to the un-optimized, fully populated design. For the rotational encoding design, the resolution uniformity is improved by 95% compared to - uniformly populated design.
Autors: Clarissa Zimmerman Cooley;Melissa W. Haskell;Stephen F. Cauley;Charlotte Sappo;Cristen D. Lapierre;Christopher G. Ha;Jason P. Stockmann;Lawrence L. Wald;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jan 2018, volume: 54, issue:1, pages: 1 - 12
Publisher: IEEE
 
» Design of TE-Polarized Bessel Antenna in Microwave Range Using Leaky-Wave Modes
Abstract:
In this paper, we present a transverse electric (TE)-polarized Bessel-beam antenna in the microwave range based on a leaky radial waveguide. According to the dispersion equation, an inductive sheet over a ground plane is needed. To achieve the inductive sheet, a grid structure printed on a dielectric substrate is designed. Besides, the radial waveguide is coaxially fed with a quasi-loop shaped structure to excite TE mode. The proposed antenna is investigated by simulation and measurement. In the measurement, a small loop is used to probe near magnetic field, and accurate measured magnetic intensity profiles are presented. The measurements show that TE-polarized Bessel beams can be launched within the nondiffractive range of 145 mm () at 5.8 GHz.
Autors: Ping Lu;Damien Voyer;Arnaud Bréard;Julien Huillery;Bruno Allard;Xuefang Lin-Shi;Xue-Song Yang;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jan 2018, volume: 66, issue:1, pages: 32 - 41
Publisher: IEEE
 
» Design of Vector Field for Different Subphases of Gait and Regeneration of Gait Pattern
Abstract:
In this paper, we have designed the vector fields (VFs) for all the six joints (hip, knee, and ankle) of a bipedal walking model. The bipedal gait is the manifestation of temporal changes in the six joints angles, two each for hip, knee, and ankle values and it is a combination of seven different discrete subphases. Developing the correct joint trajectories for all the six joints was difficult from a purely mechanics-based model due to its inherent complexities. To get the correct and exact joint trajectories, it is very essential for a modern bipedal robot to walk stably. By designing the VF correctly, we are able to get the stable joint trajectory ranges and able to reproduce angle ranges from theses designed VFs. This is purely a data driven computational modeling approach, which is based on the hypothesis that morphologically similar structure (human-robot) can adopt similar gait patterns. To validate the correctness of the design, we have applied all the possible combination of joint trajectories to HOAP-2 bipedal robot, which could walk successfully maintaining its stability. The VF provides joint trajectories for a particular joint. The results show that our data driven computational model is able to provide the correct joints angle ranges, which are stable.

Note to Practitioners—In this research, we have developed the vector field (VF) for each joint (hip, knee, and ankle) of a biped, which plays an important role in walking. The idea is noble and based on data driven computational model. The generated trajectories are applied on HOAP-2 bipedal humanoid robot and compare the two joint trajectories from VF with HOAP-2 model and hybrid automata model.

Autors: Vijay Bhaskar Semwal;Chandan Kumar;Piyush Kumar Mishra;Gora Chand Nandi;
Appeared in: IEEE Transactions on Automation Science and Engineering
Publication date: Jan 2018, volume: 15, issue:1, pages: 104 - 110
Publisher: IEEE
 
» Design of Wideband Circularly Polarized Antenna Using Coupled Rotated Vertical Metallic Plates
Abstract:
A simple structure composed of four rotated metallic plates is proposed to enhance the bandwidth of circularly polarized (CP) crossed-dipole antenna. The metallic plates are vertically added on the ground plane in a sequential rotation way, surrounding the primary radiator of the crossed-dipole antenna. Owing to the coupling with the radiator, orthogonal currents can be induced on the metallic plates. Additional impedance and axial ratio passbands can, therefore, be generated beside the original operating band, enhancing its bandwidth substantially. As the metallic plates are mounted on the ground plane, no extra footprint is needed, making the area of the wideband antenna very compact. Simulation and measured results show that by using this simple structure, the operating bandwidth of CP crossed-dipole antenna can be enhanced significantly from ~30% to 106.1%. The structure is also applicable to the intrinsically narrowband patch antennas.
Autors: Yong Mei Pan;Wan Jun Yang;Shao Yong Zheng;Peng Fei Hu;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jan 2018, volume: 66, issue:1, pages: 42 - 49
Publisher: IEEE
 
» Design Techniques for Signal Reflection Suppression in High-Speed 25-Gb/s Laser Drivers in CMOS
Abstract:
In this letter, we propose design techniques to suppress high-speed signal reflections observed in direct-modulated laser drivers. The first technique utilizes active back-termination (ABT) to absorb the reflected energy from the laser impedance mismatch. In the second design, capacitively coupled pre-emphasis (CCPE) is proposed to cancel the transient over-shooting observed from the bond-wire reflections. In order to evaluate these techniques, the two 25-Gb/s CMOS laser drivers are designed and fabricated in a standard 65-nm process. Experimental results show that both drivers exhibit clear 25.78-Gb/s optical eye-diagrams with >4 dB extinction ration, and also exhibit significant improvement in jitter performance when the ABT or CCPE is enabled.
Autors: Jingbo Shi;Bozhi Yin;Nan Qi;Rui Bai;Zhiyong Li;Zhiliang Hong;Patrick Yin Chiang;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2018, volume: 30, issue:1, pages: 39 - 42
Publisher: IEEE
 
» Design, Fabrication, and Characterization of a Low-Temperature Curable Magnetic Composite for Power Electronics Integration
Abstract:
To simplify the integration process of embedding magnetic components in power electronics converters, we fabricated a magnetic-filled-benzocyclobutene composite that can be cured at temperatures below 250 °C without pressure. The magnetic fillers used in the formulation were a round-shaped particle of permalloy and a flake-shaped particle of Metglas 2705 M. To guide the formulation, we first constructed 3-D finite-element models of the composite consisting of periodic unit cells of magnetic particles and flakes in the polymer matrix and used Ansoft Maxwell to simulate magnetic properties of the composite. Then, flowable pastes of the composite with varying amounts of Metglas in the magnetic fillers up to 12.5 wt% were prepared, and toroid cores were poured and cured at 250 °C. Subsequently, magnetic properties of the cores, i.e., complex permeability and core loss density, were measured. We found that the real part of the composite’s relative permeability increased with Metglas addition, reaching a value of 26 at 12.5%. However, the core loss data at 1 and 5 MHz showed that the addition of Metglas flakes also increased the core loss density. The measured properties were consistent with the Maxwell simulation results. Microstructures of the cores were examined by scanning electron microscopy. We found that the magnetic particles were uniformly dispersed and isolated by the polymer, which explained the high electrical resistivities of the composite and relatively low core loss densities due to suppression of inter-particle eddy-current losses.
Autors: Yi Yan;Weizhen Sun;Shan Gao;Ting Ge;Khai D. T. Ngo;Guo-Quan Lu;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jan 2018, volume: 54, issue:1, pages: 1 - 6
Publisher: IEEE
 
» Detection of an Intruder and Prediction of His State of Motion by Using Seismic Sensor
Abstract:
Detection of intruders and predicting their activities are the first and foremost needs of surveillance. An embedded system employing geophone, adaptive event extraction, and robust machine learning algorithms have made it possible not only to detect the presence of a potentially harmful intruder but also to predict to a high degree of accuracy, his state of motion, and to take counter action at the earliest. This paper aims to be an in-depth study of this simple yet effective technique of intruder detection and its subsequent predictive analysis of motion which should come as a handy aid to security solutions all-around. The proposed event extraction technique detects footfall events and extracts portions of the signal that correspond to an event. Using the classifier SVM-RBF and the proposed event extraction technique the presence of an intruder can be predicted with an accuracy of 86% from a signal of length 2 s and its state of motion with an accuracy of 77% from a signal of length 6 s.
Autors: Bodhibrata Mukhopadhyay;Sahil Anchal;Subrat Kar;
Appeared in: IEEE Sensors Journal
Publication date: Jan 2018, volume: 18, issue:2, pages: 703 - 712
Publisher: IEEE
 
» Detection of Digitally Phase-Modulated Signals Utilizing Mechanical Vibration of CNT Cantilever
Abstract:
Communication between tiny sensor nodes is an important function in future sensing applications and services. This paper contributes to the design of both the front end and the demodulator of nanoscale receivers. A nanoscale phase detector is proposed that provides two important functions at nanoscale: reception of an incoming carrier signal in the megahertz band, and detection of the carrier phase which contains the information of the transmitted digital data. These two functions are achieved by the mechanical vibration of the tip of a carbon nanotube. The proposed detector was theoretically analyzed in terms of its communication aspects; although a digitally phase-modulated signal could be detected in nanoscale, the effective received signal power showed to be strongly reduced in a key performance measure in communication systems, bit error rate. However, the present analysis reveals that the output of the proposed detector has two frequency components, which describe the transmitted data. To take the advantage of this characteristic, a demodulator using maximum-ratio combining is introduced in this paper. The optimal weights used to combine the components were analytically derived to improve the bit error rate performance. The effectiveness of the nanoscale phase detector is numerically demonstrated, and the gain relative to the demodulation achieved using a conventional simple correlator is established.
Autors: Yukihiro Tadokoro;Yutaka Ohno;Hiroya Tanaka;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Jan 2018, volume: 17, issue:1, pages: 84 - 92
Publisher: IEEE
 
» Detection of Root Orientation Using Ground-Penetrating Radar
Abstract:
Due to its in situ and nondestructive nature, ground-penetrating radar (GPR) has recently been applied to the field investigation of plant roots. The discrepancy between the roots and surrounding soils creates a dielectric constant contrast, forming clear hyperbolic reflections on the GPR radargram. The intensity and shape of the reflecting signals from roots are substantially affected by the root orientation as well as the relative geometry between the root in the subsurface and the GPR survey direction on the ground surface. However, no previous study has utilized the information on the intensity and shape of a root’s GPR reflection to map its orientation, which is crucial in interpreting radargrams and rebuilding 3-D root system architecture. In this paper, a mathematical formulation of hyperbolic reflection formed by a single root was first deduced based on the principles of electromagnetic wave propagation. Then, using this formulation, curve fitting was conducted on both simulated and field collected data sets by GPR. Information on the horizontal orientation and vertical inclination of a single root was acquired according to the formulation coefficient retrievals. Conditions for this method of application and factors impacting the extraction of root orientation information were analyzed. The results indicated fairly precise root orientation estimations. The proposed method has extended the application of GPR in root investigation, thus advancing the frontier of noninvasive root system architecture mapping.
Autors: Qixin Liu;Xihong Cui;Xinbo Liu;Jin Chen;Xuehong Chen;Xin Cao;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Jan 2018, volume: 56, issue:1, pages: 93 - 104
Publisher: IEEE
 
» Detector Based Radio Tomographic Imaging
Abstract:
Received signal strength based radio tomographic imaging is a popular device-free indoor localization method which reconstructs the spatial loss field of the environment using measurements from a dense wireless network. Existing methods achieve high accuracy localization using a complex system with many sophisticated components. In this work, we propose an alternative and simpler imaging system based on link level occupancy detection. First, we introduce a single-bounce reflection based received signal strength model, which allows relating received signal strength variations to a large region around the link-lines. Then, based on the model, we present methods for all system components including a classifier, a detector, a back-projection based reconstruction algorithm, and a localization method. The introduced system has the following advantages over the other imaging based methods: i) a simple image reconstruction method that is straightforward to implement; ii) significantly lower computational complexity such that no floating point multiplication is required; iii) each link's measured data are compressed to a single bit, providing improved scalability; and iv) physically significant and repeatable parameters. The proposed method is validated using measurement data. Results show that the proposed method achieves the above advantages without loss of accuracy compared to the other available methods.
Autors: Hüseyin Yiğitler;Riku Jäntti;Ossi Kaltiokallio;Neal Patwari;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Jan 2018, volume: 17, issue:1, pages: 58 - 71
Publisher: IEEE
 
» Detector Blur and Correlated Noise Modeling for Digital Breast Tomosynthesis Reconstruction
Abstract:
This paper describes a new image reconstruction method for digital breast tomosynthesis (DBT). The new method incorporates detector blur into the forward model. The detector blur in DBT causes correlation in the measurement noise. By making a few approximations that are reasonable for breast imaging, we formulated a regularized quadratic optimization problem with a data-fit term that incorporates models for detector blur and correlated noise (DBCN). We derived a computationally efficient separable quadratic surrogate (SQS) algorithm to solve the optimization problem that has a non-diagonal noise covariance matrix. We evaluated the SQS-DBCN method by reconstructing DBT scans of breast phantoms and human subjects. The contrast-to-noise ratio and sharpness of microcalcifications were analyzed and compared with those by the simultaneous algebraic reconstruction technique. The quality of soft tissue lesions and parenchymal patterns was examined. The results demonstrate the potential to improve the image quality of reconstructed DBT images by incorporating the system physics model. This paper is a first step toward model-based iterative reconstruction for DBT.
Autors: Jiabei Zheng;Jeffrey A. Fessler;Heang-Ping Chan;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Jan 2018, volume: 37, issue:1, pages: 116 - 127
Publisher: IEEE
 
» Determination of Minimum Detectable Deformation of Terrestrial Laser Scanning Based on Error Entropy Model
Abstract:
Terrestrial laser scanning (TLS) is a widely used remote sensing technique which can produce very dense point cloud data very promptly and is particularly suited for surface deformation monitoring. Deformation magnitude is typically estimated by comparing TLS scans over the same area but at different time epochs of interest. However, there is an issue related to such a method, which is not clear that whether the difference between two successive surveys results from the surface deformation. Hence, it is vital to determine the minimum detectable deformation (MDD) by a TLS device with a given registration and point cloud error level. In this paper, the MDD is determined based on the computation of the point cloud error entropy. The performance of the proposed method is extensively evaluated numerically using simulated plane board deformation point clouds under a range of distances and incidence angles. This proposed method was also successfully applied to deformation monitoring of one landslide test site located in the Wuhan University of Technology. The experimental results demonstrate that the theoretical MDD has a good match with the actual deformation, and the deformation greater than MDD can be accurately detected by the TLS device.
Autors: Xijiang Chen;Kegen Yu;Hao Wu;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Jan 2018, volume: 56, issue:1, pages: 105 - 116
Publisher: IEEE
 
» Determination of Nerve Fiber Diameter Distribution From Compound Action Potential: A Continuous Approach
Abstract:
When a signal is initiated in the nerve, it is transmitted along each nerve fiber via an action potential (called single fiber action potential (SFAP)) which travels with a velocity that is related with the diameter of the fiber. The additive superposition of SFAPs constitutes the compound action potential (CAP) of the nerve. The fiber diameter distribution (FDD) in the nerve can be computed from the CAP data by solving an inverse problem. This is usually achieved by dividing the fibers into a finite number of diameter groups and solve a corresponding linear system to optimize FDD. However, number of fibers in a nerve can be measured sometimes in thousands and it is possible to assume a continuous distribution for the fiber diameters which leads to a gradient optimization problem. In this paper, we have evaluated this continuous approach to the solution of the inverse problem. We have utilized an analytical function for SFAP and an assumed a polynomial form for FDD. The inverse problem involves the optimization of polynomial coefficients to obtain the best estimate for the FDD. We have observed that an eighth order polynomial for FDD can capture both unimodal and bimodal fiber distributions present in vivo, even in case of noisy CAP data. The assumed FDD distribution regularizes the ill-conditioned inverse problem and produces good results.
Autors: M. Kerem Ün;Hamed Kaghazchi;
Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Publication date: Jan 2018, volume: 26, issue:1, pages: 77 - 83
Publisher: IEEE
 
» Determination of the oxidation induction time of mineral insulating oils using a modified EN 14112 method
Abstract:
The most common cause of chemical aging of insulating oils is oxidation. Inhibited oils are insulating oils to which an oxidation inhibitor such as 2,6 ditertiary-butyl phenol or 2,6 dietertiary-butyl cresol has been added in order to slow the rate of oxidation [1]–[3]. The oxidation induction time (OIT) is the time at which the oxidation inhibitor has been exhausted.
Autors: Helena M. Wilhelm;Paulo O. Fernandes;Leandro G. Feitosa;Geovana C. Dos Santos;Giorgi Dal Pont;Andreza Balielo;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Jan 2018, volume: 34, issue:1, pages: 7 - 14
Publisher: IEEE
 
» Development of a 0.6-MV Ultracompact Magnetic Core Pulsed Transformer for High-Power Applications
Abstract:
The generation of high-power electromagnetic waves is one of the major applications in the field of high-intensity pulsed power. The conventional structure of a pulsed power generator contains a primary energy source and a load separated by a power-amplification system. The latter performs time compression of the slow input energy pulse and delivers a high-intensity power output to the load. Usually, either a Marx generator or a Tesla transformer is used as a power amplifier. In the present case, a system termed “module oscillant utilisant une nouvelle architecture” (MOUNA) uses an innovative and very compact resonant pulsed transformer to drive a dipole antenna. This paper describes the ultracompact multiprimary winding pulsed transformer developed in common by the Université de Pau and Hi Pulse Company that can generate voltage pulses of up to 0.6 MV, with a rise time of less than 270 ns. The transformer design has four primary windings, with two secondary windings in parallel, and a Metglas 2605SA1 amorphous iron magnetic core with an innovative biconic geometry used to optimize the leakage inductance. The overall unit has a weight of 6 kg and a volume of only 3.4 L, and this paper presents in detail its design procedure, with each of the main characteristics being separately analyzed. In particular, simple but accurate analytical calculations of both the leakage inductance and the stray capacitance between the primary and secondary windings are presented and successfully compared with CST-based results. Phenomena such as the core losses and saturation induction are also analyzed. The resonant power-amplifier output characteristics are experimentally studied when attached to a compact capacitive load, coupled to a capacitive voltage probe developed jointly with Loughborough University. Finally, an LTspice-based model of the power amplifier is introduced and its predictions are compared with results obtaine- from a thorough experimental study.
Autors: Laurent Pécastaing;Marc Rivaletto;Antoine Silvestre de Ferron;Romain Pecquois;Bucur M. Novac;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Jan 2018, volume: 46, issue:1, pages: 156 - 166
Publisher: IEEE
 
» Development of a high-performance indirectly hydrogen-cooled turbine generator [News from Japan]
Abstract:
Global warming caused by CO2 emission, and continuously growing power demands world-wide, are of considerable concern. Among the various types of electric power generation systems, thermal power generation is the largest emitter of CO2. Thus reducing the CO2 emission from thermal power generation plants by increasing their efficiency is an important task for the manufacturers of such plants. Thermal power plants and turbine generators are therefore required to supply electric power more efficiently, where efficiency is defined as generator efficiency.
Autors: Y. Ohki;
Appeared in: IEEE Electrical Insulation Magazine
Publication date: Jan 2018, volume: 34, issue:1, pages: 61 - 63
Publisher: IEEE
 
» Dielectric Characterization of RF-Printed Circuit Board Materials by Microstrip Transmission Lines and Conductor-Backed Coplanar Waveguides Up to 110 GHz
Abstract:
This paper introduces a method for determining the attenuation constant and the dielectric permittivity (Dk) by microstrip lines and/or conductor-backed coplanar waveguides. The method considers several effects (surface waves, frequency-dependent conductance, inductance, and resistance) for obtaining the attenuation constant of the line and the Dk of the substrate out of measurements. For the compensation of conductor properties, an easily applicable formula for any low loss transmission line is derived that avoids extensive simulations. The validity of the method is shown by measurements of two RF-substrate materials up to 110 GHz. The resulting Dk not only shows excellent agreement with available data sheet values, but also extends the investigated frequency range.
Autors: Oliver Huber;Thomas Faseth;Gottfried Magerl;Holger Arthaber;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2018, volume: 66, issue:1, pages: 237 - 244
Publisher: IEEE
 
» Differentially Private MIMO Filtering for Event Streams
Abstract:
Rigorous privacy-preserving mechanisms that can process and analyze dynamic data streams in real time are required to encourage a wider adoption of many large-scale monitoring and control systems recording the detailed activities of their users, such as intelligent transportation systems, smart grids, or smart buildings. Motivated by scenarios where signals originate from many sensors capturing privacy-sensitive events about individuals and several statistics of interest need to be continuously published in real time, we consider the problem of designing multi-input multi-output (MIMO) systems processing event streams, while providing certain differential privacy guarantees on the input signals. We show how to construct and optimize MIMO extensions of the zero-forcing mechanism, which we previously proposed for single-input single-output systems. Some of these extensions can take a statistical model of the input signals into account. We illustrate our privacy-preserving filter design methodology in two examples: privately monitoring and forecasting occupancy in a building equipped with multiple motion detection sensors, and analyzing the activity of a Markov chain model of a simple shared processing server.
Autors: Jerome Le Ny;Meisam Mohammady;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Jan 2018, volume: 63, issue:1, pages: 145 - 157
Publisher: IEEE
 
» Digital Background Calibration With Histogram of Decision Points in Pipelined ADCs
Abstract:
This brief presents a digital background calibration technique for pipelined analog-to-digital converters (ADCs). It is a histogram-based technique and called the correction with histogram of decision points (CHDP). In this method, the capacitor mismatch and residue amplifier gain error and nonlinearity are corrected by estimating the output code of decision points in the residue characteristic. In order to achieve adequate points, the threshold level of sub-ADC is changed and to increase the estimation accuracy, an algorithm named the mapping histogram is presented. CHDP does not require any special analog circuit and its digital logic is simple. Behavioral simulation results of a 12-bit 100 MS/s pipelined ADC indicate that the proposed calibration scheme improves signal-to-noise and distortion ratio and spurious free dynamic range from 34.1 and 35 dB to 68.2 and 75.8 dB, respectively, while needing about samples for the calibration of five stages.
Autors: Peyman Gholami;Mohammad Yavari;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Jan 2018, volume: 65, issue:1, pages: 16 - 20
Publisher: IEEE
 
» Digital Complex Delta–Sigma Modulators With Highly Configurable Notches for Multi-Standard Coexistence in Wireless Transmitters
Abstract:
This paper presents a complex delta–sigma modulator (CDSM) designed for integration in a digital transmitter chain targeting multi-standard coexistence with nearby receivers. The use of a DSM has the advantage of increased performance in terms of signal-to-noise-ratio in the band of interest. However, the resulting out-of-band noise becomes an issue for multi-standard coexistence, thus increasing the complexity of the subsequent filtering stage. This constraint could be relaxed in the DSM stage, by placing a complex zero near the frequency band, where a low noise level is needed. This is achieved by cross coupling the in-phase (I) and quadrature (Q) channels, thus obtaining a CDSM. A review of known design methods for CDSM revealed limitations regarding the poles/zeros optimization, and the configurability of the complex zeros placement. The proposed architecture introduces two additional cross couplings from the I and Q quantizers outputs in order to decorrelate the zeros placement and the poles optimization problem. Hence, the improved CDSM can be implemented using existing optimization tools, which reduces considerably the number of iterations and the computational effort. In addition, the resulting modulator can target different coexistence scenarios without the need of redesign, unlike other known methods. Simulation results show a noise level reduction of approximately 20–30-dB near specific frequency bands by the proposed CDSM scheme with respect to standard DSM. Finally, we show an efficient coarse/fine configurability mechanism, which is obtained when introducing additional delays in the cross-coupling paths.
Autors: Răzvan-Cristian Marin;Antoine Frappé;Andreas Kaiser;
Appeared in: IEEE Transactions on Circuits and Systems I: Regular Papers
Publication date: Jan 2018, volume: 65, issue:1, pages: 343 - 352
Publisher: IEEE
 
» Digital Imaging Tool to Enhance Otolith Microstructure for Estimating Age in Days in Juvenile and Adult Fish
Abstract:
Age estimation based on fish otolith microstructure analysis is a very repetitive and time-consuming task. The lack of appropriate image analysis software, capable of both overlaying a number of images automatically and recording a high number of daily increments, has been a significant limitation in counting and measuring daily growth increments in large otoliths from juvenile and adult fish individuals. This paper presents a new software to assist marine biologists with faster, more efficient, and more reliable microstructure readings of fish otoliths. Open source code is preferred so that software packages can be updated with new image processing algorithms developed by the scientific community. The approach consists of three steps: 1) a single grayscale digital image combining images of different parts of the same fish otolith is obtained using the blind image registration technique fast normalized cross correlation; 2) the growth rings of the image are enhanced for age estimation purposes, using the adaptive histogram equalization technique; and 3) a semiautomatic interactive tool draws a simple polygonal chain along which the microstructures are easily identifiable and the points of interest can be marked, whose data will be saved automatically. This new tool opens up the opportunity of aging juvenile and adult fish individuals at regular intervals by counting growth rings in the otolith microstructure and facilitates working with other calcified pieces of marine species that exhibit a daily ring pattern, such as cephalopod beaks and mollusk shells.
Autors: Enrique Nava;Elisa I. Villar;María C. Clemente;Javier Rey;Alberto García;Lourdes Fernández-Peralta;Carmen G. Piñeiro;Pablo Otero;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Jan 2018, volume: 43, issue:1, pages: 48 - 55
Publisher: IEEE
 
» Dimensionality Reduction on SPD Manifolds: The Emergence of Geometry-Aware Methods
Abstract:
Representing images and videos with Symmetric Positive Definite (SPD) matrices, and considering the Riemannian geometry of the resulting space, has been shown to yield high discriminative power in many visual recognition tasks. Unfortunately, computation on the Riemannian manifold of SPD matrices –especially of high-dimensional ones– comes at a high cost that limits the applicability of existing techniques. In this paper, we introduce algorithms able to handle high-dimensional SPD matrices by constructing a lower-dimensional SPD manifold. To this end, we propose to model the mapping from the high-dimensional SPD manifold to the low-dimensional one with an orthonormal projection. This lets us formulate dimensionality reduction as the problem of finding a projection that yields a low-dimensional manifold either with maximum discriminative power in the supervised scenario, or with maximum variance of the data in the unsupervised one. We show that learning can be expressed as an optimization problem on a Grassmann manifold and discuss fast solutions for special cases. Our evaluation on several classification tasks evidences that our approach leads to a significant accuracy gain over state-of-the-art methods.
Autors: Mehrtash Harandi;Mathieu Salzmann;Richard Hartley;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Jan 2018, volume: 40, issue:1, pages: 48 - 62
Publisher: IEEE
 
» Direct Least Square Fitting of Hyperellipsoids
Abstract:
This paper presents two new computationally efficient direct methods for fitting n-dimensional ellipsoids to noisy data. They conduct the fitting by minimizing the algebraic distance in subject to suitable quadratic constraints. The hyperellipsoid-specific (HES) method is an elaboration of existing ellipse and 3D ellipsoid-specific fitting methods. It is shown that HES is ellipsoid-specific in n-dimensional space. A limitation of HES is that it may provide biased fitting results with data originating from an ellipsoid with a large ratio between the longest and shortest main axis. The sum-of-discriminants (SOD) method does not have such a limitation. The constraint used by SOD rejects a subset of non-ellipsoidal quadrics, which enables a high tendency to produce ellipsoidal solutions. Moreover, a regularization technique is presented to force the solutions towards ellipsoids with SOD. The regularization technique is compatible also with several existing 2D and 3D fitting methods. The new methods are compared through extensive numerical experiments with n-dimensional variants of three commonly used direct fitting approaches for quadratic surfaces. The results of the experiments imply that in addition to the superior capability to create ellipsoidal solutions, the estimation accuracy of the new methods is better or equal to that of the reference approaches.
Autors: Martti Kesäniemi;Kai Virtanen;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Jan 2018, volume: 40, issue:1, pages: 63 - 76
Publisher: IEEE
 
» Direct Measurements of Adiabatic Temperature Change in Ni49.9Mn37.03Sb12.3Fe0.77 Alloy due to Magnetocaloric Effect in the Temperature Range of Martensitic Transformation
Abstract:
The magnetic and magnetocaloric measurements are reported for Ni49.9Mn37.03Sb12.3Fe0.77. The application of magnetic field was found to result in a shift of characteristic temperatures of the martensitic transformation (MT) by 0.7 K/T. Direct measurements of magnetocaloric effect (MCE) were employed to evaluate potential of this alloy for magnetic refrigeration. Peak values of MCE in magnetic field of 5 T were determined to be ~ −0.6 K in the interval of MT, and ~1 K in the vicinity of Curie temperature.
Autors: S. M. Konoplyuk;A. V. Mashirov;A. P Kamantsev;V. V. Koledov;A. V. Koshelev;V. G. Shavrov;V. V. Kokorin;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jan 2018, volume: 54, issue:1, pages: 1 - 4
Publisher: IEEE
 
» Direction Finding for Wideband Source Signals via Steered Effective Projection
Abstract:
A direction-of-arrival (DOA) estimation method for wideband source signals is proposed in the paper based on broadside steering. The steered effective noise subspace is constructed for each steering angle by collecting a certain number of subordinate eigenvectors of the steered array output covariance matrix according to the effective rank of its noise free version. The steered effective projection (STEP) based wideband direction finding then is realized as the steered effective noise subspace towards a true DOA of signal is shown to be: 1) orthogonal to a 1-D subspace spanned by an all-one vector with one single signal present and 2) approximately orthogonal to a 1-D subspace spanned by an all-one vector in the presence of multiple uncorrelated signals. The STEP method requires no preliminary DOA estimates for data focusing. It differs from the existing effective subspace based broad-band signal-subspace spatial spectrum (BASS-ALE) technique in three respects: 1) STEP employs the steered array output covariance matrices towards all the scanning angles while BASS-ALE takes into account only the (focused) array output covariance matrix; 2) STEP performs frequency independent effective subspace projections by constructing the steered effective noise subspace towards each scanning angle while BASS-ALE uses frequency dependent effective subspace projection by constructing only one (focused) effective noise subspace; and 3) STEP can be realized by spatial-only processing while BASS-ALE needs spatio-temporal joint processing to avoid ambiguity in frequency-angle pairs. The performance of the STEP method has been evaluated by extensive simulations, and compared with some current popular wideband DOA estimators.
Autors: Bingjie Yin;Yougen Xu;Yulin Huang;Ying Lu;Zhiwen Liu;
Appeared in: IEEE Sensors Journal
Publication date: Jan 2018, volume: 18, issue:2, pages: 741 - 751
Publisher: IEEE
 
» Direction-of-Arrival Estimation Enhancement for Closely Spaced Electrically Small Antenna Array
Abstract:
In this paper, compact direction finding systems using a scatterer of a high dielectric constant in between adjacent closely spaced electrically small antennas are examined. By adding a high-permittivity scatterer, the directional sensitivity can be enhanced. However, due to limited physical dimension, an electrically small antenna has highly reactive impedance. To enhance the received power level, a matching network is included. The highest directional sensitivity satisfying a given power constraint is compared for with and without scatterer cases. In addition, widely used matching approaches such as multiport-conjugate matching (MCM), self-conjugate matching (SCM), and eigenmode decoupling matching are investigated to increase the received power. The impact of these matching networks on the directional sensitivity is studied. The power and the directional-sensitivity bandwidth after matching are also analyzed. Finally, the two-monopole and a high-permittivity scatterer system with SCM and MCM circuits is fabricated and tested.
Autors: Xiaoju Yu;Hao Xin;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2018, volume: 66, issue:1, pages: 477 - 484
Publisher: IEEE
 
» Direction-of-Arrival Estimation in Conformal Microstrip Patch Array Antenna
Abstract:
The direction-of-arrival (DOA) estimation of a conformal antenna array with directive elements is studied in this communication. The two-dimension Cramer–Rao lower bound (CRLB) is derived for a conformal antenna array by using the active directive radiation patterns of the array elements and compared with the isotropic ones. Moreover, the MUSIC method is used to confirm the CRLB results. Without loss of generality, the CRLB of a truncated hexagonal pyramid conformal array with seven patches is investigated which verify the significant effect of the directive elements in the DOA estimation accuracy rather than that of the isotropic ones. The simulation results prove that this conformal array achieves better DOA estimation performance rather than that of the planar array antenna especially at the horizon angles. Moreover, the conformal antenna array tilt angle is studied to achieve the optimum conformal array structure which depicts a tradeoff between the DOA estimation accuracy at low and high incident angles.
Autors: Sirous Mohammadi;Armin Ghani;Seyed Hassan Sedighy;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jan 2018, volume: 66, issue:1, pages: 511 - 515
Publisher: IEEE
 
» Directional Enhancement Analysis of All-Dielectric Optical Nanoantennas Based on SIE Formulation
Abstract:
Recent advances in optical nanoantennas made of high-permittivity low-loss dielectric particles have demanded efficient numerical modeling techniques for electromagnetic radiation and scattering simulations. Here, the facing requirements of fast convergence of iteration methods and good accuracy of results, a modified surface integral equation for high-permittivity objects has been presented. Moreover, based on the proposed surface integral equation, a full study of the dependence of the radiation pattern on the relative permittivity and wavelength has been performed for a single-dielectric nanoparticle with the excitation of an electric dipole source. Then, the directional enhancement of radiation is explored from Yagi-Uda geometry systems made of nanoparticles with optimal permittivities for reflector and directors.
Autors: Xin Qi;Zaiping Nie;Yongpin Chen;Xiaofeng Que;Jun Hu;Yue Wang;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2018, volume: 30, issue:1, pages: 123 - 126
Publisher: IEEE
 
» Discrete Fresnel Transform Spread OFDM for Coherent Optical Fiber Communication
Abstract:
In the polarization-division multiplexed coherent optical fiber communication, conventional orthogonal frequency-division multiplexing (OFDM) and discrete Fourier transform spread OFDM (DFT-S-OFDM) sacrifice the baud rate with either zero-padded subcarriers in the high-frequency region to mitigate the frequency fading, or with a large cyclic prefix (CP) to eliminate the residual inter-symbol interference (ISI). In this letter, we propose a discrete Fresnel transform spread OFDM (DFnT-S-OFDM) scheme, which spreads information over both temporal and frequency dimensions. A low-complexity encoder was also developed for the proposed precoding scheme. Simulations show that DFnT-S-OFDM is more resilient against the frequency fading than OFDM and against the residual ISI than DFT-S-OFDM. Therefore, it maximizes the net data rate by reducing the CP length or increasing the useful signal bandwidth.
Autors: Yukui Yu;Wei Wang;Xing Ouyang;Zhenpeng Wang;Jian Zhao;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2018, volume: 30, issue:1, pages: 91 - 94
Publisher: IEEE
 
» Discriminative Dimensionality Reduction for Multi-Dimensional Sequences
Abstract:
Since the observables at particular time instants in a temporal sequence exhibit dependencies, they are not independent samples. Thus, it is not plausible to apply i.i.d. assumption-based dimensionality reduction methods to sequence data. This paper presents a novel supervised dimensionality reduction approach for sequence data, called Linear Sequence Discriminant Analysis (LSDA). It learns a linear discriminative projection of the feature vectors in sequences to a lower-dimensional subspace by maximizing the separability of the sequence classes such that the entire sequences are holistically discriminated. The sequence class separability is constructed based on the sequence statistics, and the use of different statistics produces different LSDA methods. This paper presents and compares two novel LSDA methods, namely M-LSDA and D-LSDA. M-LSDA extracts model-based statistics by exploiting the dynamical structure of the sequence classes, and D-LSDA extracts the distance-based statistics by computing the pairwise similarity of samples from the same sequence class. Extensive experiments on several different tasks have demonstrated the effectiveness and the general applicability of the proposed methods.
Autors: Bing Su;Xiaoqing Ding;Hao Wang;Ying Wu;
Appeared in: IEEE Transactions on Pattern Analysis and Machine Intelligence
Publication date: Jan 2018, volume: 40, issue:1, pages: 77 - 91
Publisher: IEEE
 
» Dispersion Analysis of 2-D Glide-Symmetric Corrugated Metasurfaces Using Mode-Matching Technique
Abstract:
In this letter, wave propagation in 2-D doubled corrugated metasurfaces, including glide-symmetric corrugated metasurfaces, embedded in a thin parallel plate waveguide have been analyzed using the mode matching method. The general dispersion equation for propagation at different directions is derived and dispersion surfaces have been obtained for three different cases. The results are in good agreement with reference results obtained using CST Microwave Studio. Moreover, the method is accurate and computationally much faster than CST Microwave Studio and similar commercial software.
Autors: Fatemeh Ghasemifard;Martin Norgren;Oscar Quevedo-Teruel;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jan 2018, volume: 28, issue:1, pages: 1 - 3
Publisher: IEEE
 
» Distortion Correction in Fetal EPI Using Non-Rigid Registration With a Laplacian Constraint
Abstract:
Geometric distortion induced by the main B0 field disrupts the consistency of fetal echo planar imaging (EPI) data, on which diffusion and functional magnetic resonance imaging is based. In this paper, we present a novel data-driven method for simultaneous motion and distortion correction of fetal EPI. A motion-corrected and reconstructed T2 weighted single shot fast spin echo (ssFSE) volume is used as a model of undistorted fetal brain anatomy. Our algorithm interleaves two registration steps: estimation of fetal motion parameters by aligning EPI slices to the model; and deformable registration of EPI slices to slices simulated from the undistorted model to estimate the distortion field. The deformable registration is regularized by a physically inspired Laplacian constraint, to model distortion induced by a source-free background B0 field. Our experiments show that distortion correction significantly improves consistency of reconstructed EPI volumes with ssFSE volumes. In addition, the estimated distortion fields are consistent with fields calculated from acquired field maps, and the Laplacian constraint is essential for estimation of plausible distortion fields. The EPI volumes reconstructed from different scans of the same subject were more consistent when the proposed method was used in comparison with EPI volumes reconstructed from data distortion corrected using a separately acquired B0 field map.
Autors: Maria Kuklisova-Murgasova;Georgia Lockwood Estrin;Rita G. Nunes;Shaihan J. Malik;Mary A. Rutherford;Daniel Rueckert;Joseph V. Hajnal;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Jan 2018, volume: 37, issue:1, pages: 12 - 19
Publisher: IEEE
 
» Distributed Control of PEV Charging Based on Energy Demand Forecast
Abstract:
This paper presents a new distributed smart charging strategy for grid integration of plug-in electric vehicles (PEVs). The main goal is to smooth the daily grid load profile while ensuring that each PEV has a desired state of charge level at the time of departure. Communication and computational overhead, and PEV user privacy are also considered during the development of the proposed strategy. It consists of two stages: 1) an offline process to estimate a reference operating power level based on the forecasted mobility energy demand and base loading profile, and 2) a real-time process to determine the charging power for each PEV so that the aggregated load tracks the reference loading level. Tests are carried out both on primary and secondary distribution networks for different heuristic charging scenarios and PEV penetration levels. Results are compared to that of the optimal solution and other state-of-the-art techniques in terms of variance and peak values, and shown to be competitive. Finally, a real vehicle test implementation is done using a commercial-of-the-shelf charging station and an electric vehicle.
Autors: Mithat C. Kisacikoglu;Fatih Erden;Nuh Erdogan;
Appeared in: IEEE Transactions on Industrial Informatics
Publication date: Jan 2018, volume: 14, issue:1, pages: 332 - 341
Publisher: IEEE
 
» Distributed Event-Based State Estimation for Networked Systems: An LMI Approach
Abstract:
In this paper, a dynamic system is controlled by multiple sensor-actuator agents, each of them commanding and observing parts of the system's input and output. The different agents sporadically exchange data with each other via a common bus network according to local event-triggering protocols. From these data, each agent estimates the complete dynamic state of the system and uses its estimate for feedback control. We propose a synthesis procedure for designing the agents’ state estimators and the event triggering thresholds. The resulting distributed and event-based control system is guaranteed to be stable and to satisfy a predefined estimation performance criterion. The approach is applied to the control of a vehicle platoon, where the method's tradeoff between performance and communication and the scalability in the number of agents are demonstrated.
Autors: Michael Muehlebach;Sebastian Trimpe;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Jan 2018, volume: 63, issue:1, pages: 269 - 276
Publisher: IEEE
 
» Distributed Joint Source-Channel Decoding Using Systematic Polar Codes
Abstract:
This letter proposes a novel joint decoding scheme for correlated sources using systematic polar codes. In the proposed scheme, each source independently encodes its message into a systematic polar code word and sends the codeword via a binary-input additive white Gaussian noise channel to the common destination, where adaptive cyclic redundancy check-aided successive cancellation list (CA-SCL) decoders are employed. During the iterative decoding process, the log likelihood ratios (LLRs) fed to each adaptive CA-SCL decoder are iteratively combined with the extrinsic LLRs from other decoders. The correlation among the sources is exploited to improve the decoding performance. Simulation results show that, in comparison with independent decoding, the proposed scheme can achieve significantly improved decoding performance without increased complexity.
Autors: Liqiang Jin;Pei Yang;Hongwen Yang;
Appeared in: IEEE Communications Letters
Publication date: Jan 2018, volume: 22, issue:1, pages: 49 - 52
Publisher: IEEE
 
» Distributed Linearized Alternating Direction Method of Multipliers for Composite Convex Consensus Optimization
Abstract:
Given an undirected graph of agents connected with edges in , we study how to compute an optimal decision on which there is consensus among agents and that minimizes the sum of agent-specific private convex composite functions , where belongs to agent-. Assuming only agents connected by an edge can communicate, we propose a distributed proximal gradient algorithm (DPGA) for consensus optimization over both unweighted and weighted static (undirected) communication networks. In one iteration, each agent- computes the prox map of and gradient of , and this is followed by local communication with neighboring agents. We also study its stochastic gradient variant, SDPGA, which can only access to noisy estimates of at each agent-. This computational model abstracts a number of applications in distributed sensing, machine learning and statistical inference. We show ergodic convergence in both suboptimality error and consensus violation for the DPGA and SDPGA with rates and , respectively.
Autors: N. S. Aybat;Z. Wang;T. Lin;S. Ma;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Jan 2018, volume: 63, issue:1, pages: 5 - 20
Publisher: IEEE
 
» Distributed Measurement of Fermi–Pasta–Ulam Recurrence in Optical Fibers
Abstract:
We experimentally demonstrate the distributed measurement of Fermi–Pasta–Ulam (FPU) recurrence in an optical fiber. Square-shaped pulses with weak modulation are injected into a single-mode fiber to exhibit FPU recurrence. Rayleigh backscattering signals of various sidebands are recorded to measure the power vibration along the optical fiber. The validity of the distributed method is confirmed both by the numerical simulation and the cutting-back method. Compared with the traditional cutting-back method, the distributed method has significant advantages, such as short measurement time, low cost, and good repeatability. We also believe that the distributed method has a great potential for the measurement of other nonlinear effects in optical fiber.
Autors: Xiaoyang Hu;Wei Chen;Yang Lu;Zhijie Yu;Mo Chen;Zhou Meng;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2018, volume: 30, issue:1, pages: 47 - 50
Publisher: IEEE
 
» Distributed Partitioning Algorithms for Locational Optimization of Multiagent Networks in SE(2)
Abstract:
This paper is concerned with the development of distributed spatial partitioning algorithms for locational optimization problems involving networks of agents with planar rigid body dynamics subject to communication constraints. The domain of the problems we consider is a three-dimensional (3-D) nonflat manifold embedded in the state space of the agents, which we refer to as the terminal manifold. The approach we propose allows us to associate the partition of the 3-D terminal manifold, which is induced by a nonquadratic proximity metric and comprised of nonconvex cells, with a one-parameter family of partitions of 2-D flat manifolds, which are induced by (parametric) quadratic proximity metrics and comprised of convex polygonal cells. By exploiting the special structure of the parametric partitions, we develop distributed partitioning algorithms that converge in a finite number of steps. Subsequently, we utilize the solutions to the latter problems to solve a class of locational optimization problems over the terminal manifold. Numerical simulations that illustrate the capabilities of the proposed algorithms are also presented.
Autors: Efstathios Bakolas;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Jan 2018, volume: 63, issue:1, pages: 101 - 116
Publisher: IEEE
 
» Distributed Sequential Estimation in Wireless Sensor Networks
Abstract:
This paper considers the problem of decentralized sequential estimation in dynamic wireless sensor networks. A coherent medium access control layer is considered, and optimal linear precoder and decoder matrices are designed to minimize the mean square error (MSE) in an online setting. Different from the state-of-the-art decentralized estimators, the proposed framework is flexible enough to handle time-varying parameters, channel gains, and power constraints. Although the general transceiver design problem is nonconvex, a fast block coordinate descent-based method is proposed that incurs very low complexity and yields near-optimal solutions. Motivated by the need to reduce the communication overhead incurred by the centralized schemes, two fully distributed transceiver design algorithms that make use of the constrained linear minimum MSE machinery are also advocated. The resulting approximate precoders are not only near optimal but can also be calculated locally at each sensor. Finally, the entire framework is generalized so as to allow tracking of parameters that follow a known state-space model. Extensive simulations are provided to demonstrate the efficacy of the proposed class of algorithms.
Autors: Javed Akhtar;Ketan Rajawat;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Jan 2018, volume: 17, issue:1, pages: 86 - 100
Publisher: IEEE
 
» Distribution Optimal Power Flow With Real-Time Price Elasticity
Abstract:
This letter investigates a new class of optimal power flow problem for distribution systems, where elastic loads respond to real-time nodal prices by adjusting their demands. A fixed-point iteration algorithm is suggested to identify an equilibrium. A concise criterion is devised to judge convergence.
Autors: Wei Wei;Jianhui Wang;Lei Wu;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2018, volume: 33, issue:1, pages: 1097 - 1098
Publisher: IEEE
 
» Distributionally Robust Contingency-Constrained Unit Commitment
Abstract:
This paper proposes a distributionally robust optimization approach for the contingency-constrained unit commitment problem. In our approach, we consider a case where the true probability distribution of contingencies is ambiguous, i.e., difficult to accurately estimate. Instead of assigning a (fixed) probability estimate for each contingency scenario, we consider a set of contingency probability distributions (termed the ambiguity set) based on the security criterion and moment information. Our approach considers all possible distributions in the ambiguity set, and is hence distributionally robust. Meanwhile, as this approach utilizes moment information, it can benefit from available data and become less conservative than the robust optimization approaches. We derive an equivalent reformulation and study a Benders’ decomposition algorithm for solving the model. Furthermore, we extend the model to incorporate wind power uncertainty. The case studies on a 6-Bus system and the IEEE 118-Bus system demonstrate that the proposed approach provides less conservative unit commitment decisions as compared with the robust optimization approach.
Autors: Chaoyue Zhao;Ruiwei Jiang;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2018, volume: 33, issue:1, pages: 94 - 102
Publisher: IEEE
 
» Distributionally Robust Optimal Bidding of Controllable Load Aggregators in the Electricity Market
Abstract:
An optimal bidding model of controllable loads is proposed to minimize the worst-case conditional expectation of electricity purchase cost simultaneously in day-ahead and real-time markets. By reformulating the worst-case conditional value-at-risk (CVaR) constraints, a solvable semi-definite program (SDP) is presented to relax the moment uncertainty of electricity price and simultaneously determine the optimal day-ahead bid and real-time increment/decrement bid.
Autors: Hongming Yang;Shiming Zhang;Duo Qiu;Junhua Zhao;Mingyong Lai;Zhao Yang Dong;Zhao Hui Dong;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2018, volume: 33, issue:1, pages: 1089 - 1091
Publisher: IEEE
 
» Disturbance Compensation With Finite Spectrum Assignment for Plants With Input Delay
Abstract:
This paper presents a method for compensation of unknown bounded smooth disturbances for linear time invariant (LTI) plants with known parameters in the presence of constant and known input delay. The proposed control law is a sum of the classical predictor suggested by Manitius and Olbrot for finite spectrum assignment and a disturbance compensator. The disturbance compensator is a novel control law based on the auxiliary loop for disturbance extraction and on the disturbance prediction. A numerical implementation of the integral terms in the predictor-based control law is studied and sufficient conditions in terms of linear matrix inequalities are provided for an estimate on the maximum delay that preserves the stability. Numerical examples illustrate the efficiency of the method.
Autors: Igor Furtat;Emilia Fridman;Alexander Fradkov;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Jan 2018, volume: 63, issue:1, pages: 298 - 305
Publisher: IEEE
 
» Divergence-Conforming Constrained Basis Functions for Hexahedral Volume Elements
Abstract:
This communication presents an algebraic method for constructing arbitrary-order, divergence-conforming basis functions on hexahedral volume elements. The appropriate constraints within and on the boundaries of elements are provided. In particular, the handling of faces where quantities are discontinuous is discussed. The resulting bases are numerically characterized in terms of error convergence and system conditioning for a moment method discretization of the electric field volume integral equation for dielectric scatterers. Results show the accuracy of the proposed method as well as the low system matrix condition number that can be maintained as the basis order and mesh discretization are increased.
Autors: Robert A. Pfeiffer;John C. Young;Robert J. Adams;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jan 2018, volume: 66, issue:1, pages: 501 - 504
Publisher: IEEE
 
» Diversity-Promoting Deep Structural Metric Learning for Remote Sensing Scene Classification
Abstract:
Deep models with multiple layers have demonstrated their potential in learning abstract and invariant features for better representation and classification of remote sensing images. Moreover, metric learning (ML) is usually introduced into the deep models to further increase the discrimination of deep representations. However, the usual deep ML methods treat the training samples in each training batch in the stochastic gradient descent-based learning procedure independently, and thus, they neglect the important contextual (structural) information in the training samples. In this paper, we first introduce deep structural ML (DSML) into the literature of remote sensing scene classification and specifically capture and use the structural information during the training on the remote sensing images. Further analysis demonstrates that DSML usually makes many learned metric parameters similar. This similarity leads to obvious model redundancy and thus decreases the representational ability of the model. To address this problem, this paper proposes a new diversity-promoting DSML (D-DSML) method by regularizing the learning procedure by a diversity-promoting prior over the parameter factors. The proposed D-DSML encourages the parameter factors to be uncorrelated, such that each factor can model unique information, and thus, the model’s description ability and classification performance would be significantly improved. Experiments over six real-world remote sensing scene data sets demonstrate that the proposed method obtains much better results than those obtained by the original deep models and has comparable or even better performances when compared with state-of-the-art methods.
Autors: Zhiqiang Gong;Ping Zhong;Yang Yu;Weidong Hu;
Appeared in: IEEE Transactions on Geoscience and Remote Sensing
Publication date: Jan 2018, volume: 56, issue:1, pages: 371 - 390
Publisher: IEEE
 
» DIY for Engineers [MicroBusiness]
Abstract:
Reports on the concept of DIY (do-it-yourself) as it applies to microwave engineers.
Autors: Fred Schindler;
Appeared in: IEEE Microwave Magazine
Publication date: Jan 2018, volume: 19, issue:1, pages: 14 - 16
Publisher: IEEE
 
» Do Convolutional Neural Networks Learn Class Hierarchy?
Abstract:
Convolutional Neural Networks (CNNs) currently achieve state-of-the-art accuracy in image classification. With a growing number of classes, the accuracy usually drops as the possibilities of confusion increase. Interestingly, the class confusion patterns follow a hierarchical structure over the classes. We present visual-analytics methods to reveal and analyze this hierarchy of similar classes in relation with CNN-internal data. We found that this hierarchy not only dictates the confusion patterns between the classes, it furthermore dictates the learning behavior of CNNs. In particular, the early layers in these networks develop feature detectors that can separate high-level groups of classes quite well, even after a few training epochs. In contrast, the latter layers require substantially more epochs to develop specialized feature detectors that can separate individual classes. We demonstrate how these insights are key to significant improvement in accuracy by designing hierarchy-aware CNNs that accelerate model convergence and alleviate overfitting. We further demonstrate how our methods help in identifying various quality issues in the training data.
Autors: Alsallakh Bilal;Amin Jourabloo;Mao Ye;Xiaoming Liu;Liu Ren;
Appeared in: IEEE Transactions on Visualization and Computer Graphics
Publication date: Jan 2018, volume: 24, issue:1, pages: 152 - 162
Publisher: IEEE
 
» Document Summarization for Answering Non-Factoid Queries
Abstract:
We formulate a document summarization method to extract passage-level answers for non-factoid queries, referred to as answer-biased summaries. We propose to use external information from related Community Question Answering (CQA) content to better identify answer bearing sentences. Three optimization-based methods are proposed: (i) query-biased, (ii) CQA-answer-biased, and (iii) expanded-query-biased, where expansion terms were derived from related CQA content. A learning-to-rank-based method is also proposed that incorporates a feature extracted from related CQA content. Our results show that even if a CQA answer does not contain a perfect answer to a query, their content can be exploited to improve the extraction of answer-biased summaries from other corpora. The quality of CQA content is found to impact on the accuracy of optimization-based summaries, though medium quality answers enable the system to achieve a comparable (and in some cases superior) accuracy to state-of-the-art techniques. The learning-to-rank-based summaries, on the other hand, are not significantly influenced by CQA quality. We provide a recommendation of the best use of our proposed approaches in regard to the availability of different quality levels of related CQA content. As a further investigation, the reliability of our approaches was tested on another publicly available dataset.
Autors: Evi Yulianti;Ruey-Cheng Chen;Falk Scholer;W. Bruce Croft;Mark Sanderson;
Appeared in: IEEE Transactions on Knowledge and Data Engineering
Publication date: Jan 2018, volume: 30, issue:1, pages: 15 - 28
Publisher: IEEE
 
» Double ErrP Detection for Automatic Error Correction in an ERP-Based BCI Speller
Abstract:
Brain-computer interface (BCI) is a useful device for people with severe motor disabilities. However, due to its low speed and low reliability, BCI still has a very limited application in daily real-world tasks. This paper proposes a P300-based BCI speller combined with a double error-related potential (ErrP) detection to automatically correct erroneous decisions. This novel approach introduces a second error detection to infer whether wrong automatic correction also elicits a second ErrP. Thus, two single-trial responses, instead of one, contribute to the final selection, improving the reliability of error detection. Moreover, to increase error detection, the evoked potential detected as target by the P300 classifier is combined with the evoked error potential at a feature-level. Discriminable error and positive potentials (response to correct feedback) were clearly identified. The proposed approach was tested on nine healthy participants and one tetraplegic participant. The online average accuracy for the first and second ErrPs were 88.4% and 84.8%, respectively. With automatic correction, we achieved an improvement around 5% achieving 89.9% in spelling accuracy for an effective 2.92 symbols/min. The proposed approach revealed that double ErrP detection can improve the reliability and speed of BCI systems.
Autors: Aniana Cruz;Gabriel Pires;Urbano J. Nunes;
Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Publication date: Jan 2018, volume: 26, issue:1, pages: 26 - 36
Publisher: IEEE
 
» Double-Stage Delay Multiply and Sum Beamforming Algorithm: Application to Linear-Array Photoacoustic Imaging
Abstract:
Photoacoustic imaging (PAI) is an emerging medical imaging modality capable of providing high spatial resolution of Ultrasound (US) imaging and high contrast of optical imaging. Delay-and-Sum (DAS) is the most common beamforming algorithm in PAI. However, using DAS beamformer leads to low resolution images and considerable contribution of off-axis signals. A new paradigm namely delay-multiply-and-sum (DMAS), which was originally used as a reconstruction algorithm in confocal microwave imaging, was introduced to overcome the challenges in DAS. DMAS was used in PAI systems and it was shown that this algorithm results in resolution improvement and sidelobe degrading. However, DMAS is still sensitive to high levels of noise, and resolution improvement is not satisfying. Here, we propose a novel algorithm based on DAS algebra inside DMAS formula expansion, double stage DMAS (DS-DMAS), which improves the image resolution and levels of sidelobe, and is much less sensitive to high level of noise compared to DMAS. The performance of DS-DMAS algorithm is evaluated numerically and experimentally. The resulted images are evaluated qualitatively and quantitatively using established quality metrics including signal-to-noise ratio (SNR), full-width-half-maximum (FWHM) and contrast ratio (CR). It is shown that DS-DMAS outperforms DAS and DMAS at the expense of higher computational load. DS-DMAS reduces the lateral valley for about 15 dB and improves the SNR and FWHM better than 13% and 30%, respectively. Moreover, the levels of sidelobe are reduced for about 10 dB in comparison with those in DMAS.
Autors: Moein Mozaffarzadeh;Ali Mahloojifar;Mahdi Orooji;Saba Adabi;Mohammadreza Nasiriavanaki;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Jan 2018, volume: 65, issue:1, pages: 31 - 42
Publisher: IEEE
 
» Downlink Cellular Network Analysis With LOS/NLOS Propagation and Elevated Base Stations
Abstract:
In this paper, we investigate the downlink performance of dense cellular networks with elevated base stations (BSs) using a channel model that incorporates line-of-sight (LOS)/non-line-of-sight (NLOS) propagation into both small-scale and large-scale fading. Modeling LOS fading with Nakagami- fading, we provide a unified framework based on stochastic geometry that encompasses both closest and strongest BS association. This paper is particularized to two distance-dependent LOS/NLOS models of practical interest. Considering the effect of LOS propagation alone, we derive closed-form expressions for the coverage probability with Nakagami- fading, showing that the performance for strongest BS association is the same as in the case of Rayleigh fading, whereas for closest BS association it monotonically increases with the shape parameter . Then, focusing on the effect of elevated BSs, we show that network densification eventually leads to near-universal outage even for moderately low BS densities: in particular, the maximum area spectral efficiency is proportional to the inverse of the square of the BS height.
Autors: Italo Atzeni;Jesús Arnau;Marios Kountouris;
Appeared in: IEEE Transactions on Wireless Communications
Publication date: Jan 2018, volume: 17, issue:1, pages: 142 - 156
Publisher: IEEE
 
» DPPDL: A Dynamic Partial-Parallel Data Layout for Green Video Surveillance Storage
Abstract:
Video surveillance requires storing massive amounts of video data, which results in the rapid increasing of storage energy consumption. With the popularization of video surveillance, green storage for video surveillance is very attractive. The existing energy-saving methods for massive storage mostly concentrate on the data centers, mainly with random access, whereas the storage of video surveillance has inherent workload characteristics and access pattern, which can be fully exploited to save more energy. A dynamic partial-parallel data layout (DPPDL) is proposed for green video surveillance storage. It adopts a dynamic partial-parallel strategy, which dynamically allocates the storage space with an appropriate degree of partial parallelism according to performance requirement. Partial parallelism benefits energy conservation by scheduling only partial disks to work; a dynamic degree of parallelism can provide appropriate performances for various intensity workloads. DPPDL is evaluated by a simulated video surveillance consisting of 60–300 cameras with pixels. The experiment shows that DPPDL is most energy efficient, while tolerating single disk failure and providing more than 20% performance margin. On average, it saves 7%, 19%, 31%, 36%, 56%, and 59% more energy than a CacheRAID, Semi-RAID, Hibernator, MAID, eRAID5, and PARAID, respectively.
Autors: Zhizhuo Sun;Quanxin Zhang;Yuanzhang Li;Yu-An Tan;
Appeared in: IEEE Transactions on Circuits and Systems for Video Technology
Publication date: Jan 2018, volume: 28, issue:1, pages: 193 - 205
Publisher: IEEE
 
» Drain Current Saturation in Line Tunneling-Based TFETs: An Analog Design Perspective
Abstract:
This paper highlights the output current saturation in a line tunneling-based tunnel FET (LT-TFET). Thereafter, a novel method to extract the onset of saturation voltage () for LT-TFET is proposed for the first time. A soft saturation state is attained when the electron density in the epitaxial layer over the source region saturates with the drain bias () and the conduction band energy () gets pinned. In addition, at the onset of deep saturation, the electron density in the epitaxial layer over the channel region drops below its doping level and becomes invariant for any further increase in . The difference between gate–drain bias () is found to be a constant at the onset of saturation and remains independent of the gate–source overlap lengths (). A shift in and is also observed with change in the thickness and doping of the epitaxial layer. The transconductance and output resistance are reasonably good in the soft saturation regime. Furthermore, a nominal change of ~5% in the voltage gain ( ${A}_{textsf {V}}$ - /inline-formula>) of a common source amplifier is observed when the n-device is biased in the either soft or deep saturation regime, without any tradeoff in the bandwidth.
Autors: Abhishek Acharya;Abhishek B. Solanki;Sudeb Dasgupta;Bulusu Anand;
Appeared in: IEEE Transactions on Electron Devices
Publication date: Jan 2018, volume: 65, issue:1, pages: 322 - 330
Publisher: IEEE
 
» Dual-Band Coil Module With Repeaters for Diverse Wireless Power Transfer Applications
Abstract:
Dual-band coil modules facilitate efficient access to distinct-band, high-power, or rapid-charging wireless power transfer (WPT) systems. However, they do not function efficiently when the frequency ratio between two operating frequencies is large. To overcome this problem, we propose enhanced dual-band coil modules that adopt repeaters in the WPT system. We present a circuit-based analysis of repeaters in various dual-band coil modules compared with those in a single-band WPT system. The analytical results provide a design methodology applicable to diverse types of dual-band coil modules with a repeater in the WPT system. Our experimental results are consistent with the circuit-based analysis: coil power transfer efficiencies of 55% at 200 kHz and 74% at 6.78 MHz were obtained concurrently in the dual-band WPT system with a dual-band repeater. This paper reduced the application constraint of dual-band coil modules and facilitated the realization and application of multiband WPT systems.
Autors: Ming-Lung Kung;Ken-Huang Lin;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jan 2018, volume: 66, issue:1, pages: 332 - 345
Publisher: IEEE
 
» Dual-Core Fiber Optical Parametric Amplifiers With a General Pump Configuration
Abstract:
In this letter, we study a dual-core fiber optical parametric amplifier with its pumps having the arbitrary power and phase distributions. A full analytical model is derived for such a general pumping scheme based on the rotating wave approximation, which is valid under the relatively strong coupling assumption. It is found that the parametric gain is not dependent on the coupling strength between the cores in such a dual-core fiber amplifier especially in the strong coupling regime. Based on the model and the corresponding observations, it is possible to provide an efficient analytical tool for the dual-core fiber optical parametric amplifier design and performance evaluation.
Autors: Junhe Zhou;Qinsong Hu;Jianjie Wu;Wei Chen;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2018, volume: 30, issue:1, pages: 19 - 22
Publisher: IEEE
 
» Dualfunction Dielectric Resonator as Antenna and Phase-Delay-Line Load: Designs of Compact Circularly Polarized/Differential Antennas
Abstract:
Dualfunction cylindrical dielectric resonator (DR) used as the load of a broadband phase delay line (PDL) and as a DR antenna (DRA) is presented for the first time. In the broadband PDL design, the cylindrical DR is used as the load to improve impedance match and phase shift. At the same time, the delay line is used to feed the same DR for the antenna part. By designing 90° and 180° PDLs, circularly polarized (CP) and differential DRAs can be obtained, respectively. As compared with those using a hybrid coupler, the new CP and differential DRAs can be made much more compact. Also, the external load required by the hybrid coupler can now be avoided. For demonstration, two CP and differential cylindrical DRAs for 2.4 GHz WLAN applications are designed, fabricated, and tested. Good agreement between the measured and simulated results is observed. The CP design has an overlapping axial ratio and impedance passband of 24.2%. For the differential design, a broadside radiation mode with very low cross-polarization level is obtained.
Autors: Yu-Xiang Sun;Kwok Wa Leung;Jun-Fa Mao;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jan 2018, volume: 66, issue:1, pages: 414 - 419
Publisher: IEEE
 
» Duality of Channels and Codes
Abstract:
For any given channel with classical inputs and possibly quantum outputs, a dual classical-input channel can be defined by embedding the original into a channel with quantum inputs and outputs. Here, we give new uncertainty relations for a general class of entropies that lead to very close relationships between the original channel and its dual. Moreover, we show that channel duality can be combined with duality of linear codes, whereupon the uncertainty relations imply that the performance of a given code over a given channel is entirely characterized by the performance of the dual code on the dual channel. This has several applications. In the context of polar codes, it implies that the rates of polarization to ideal and useless channels must be identical. Duality also relates the tasks of channel coding and privacy amplification, implying that the finite blocklength performance of extractors and codes is precisely linked, and those optimal rate extractors can be transformed into capacity-achieving codes, and vice versa. Finally, duality also extends to the EXIT function of any channel and code. Here, it implies that for any channel family, if the EXIT function for a fixed code has a sharp transition, then it must be such that the rate of the code equals the capacity at the transition. This gives a different route to proving a code family achieves capacity by establishing sharp EXIT function transitions.
Autors: Joseph M. Renes;
Appeared in: IEEE Transactions on Information Theory
Publication date: Jan 2018, volume: 64, issue:1, pages: 577 - 592
Publisher: IEEE
 
» Dynamic Choke Sensing for Timing Error Resilience in NTC Systems
Abstract:
Process variation (PV) is a conspicuous predicament for submicrometer VLSI circuits. In this paper, we illustrate “choke points” as a vital consequence of PV in the near-threshold computing domain. Choke points are PV affected sensitized logic gates with increased delay deviation. They dominate the choice of critical paths postfabrication. To mitigate the timing errors induced thereby, we propose dynamic choke sensing (DCS). This technique senses the timing error causing opcode sequences, and uses the knowledge to prevent similar sequences from causing errors in the future. We propose two variants of our scheme. Our techniques provide ~55% improvement in performance and ~73% improvement in energy efficiency as compared with popular timing error mitigation scheme, Razor, with minimal area and power overheads.
Autors: Aatreyi Bal;Shamik Saha;Sanghamitra Roy;Koushik Chakraborty;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Jan 2018, volume: 26, issue:1, pages: 1 - 10
Publisher: IEEE
 
» Dynamic Data Transmission Technology Designed for Expendable Current Profiler
Abstract:
The dynamic data transmission technology of an expendable current profiler is proposed in this paper. Two parallel varnished wires are employed as the data transmission medium. By testing the transmission properties of the varnished wires, a baseband transmission system is studied and designed. An optocoupler is used as the physical layer for data transmission. The data transmission protocol is modified and optimized in accordance with the RS232 protocol, and the Manchester code is superimposed. According to the results of indoor and marine tests, the data transmission distance of the designed system, which employed a 0.1-mm-diameter varnished wire, extends to 2 km with high accuracy for data transmission, exhibiting excellent performance. Moreover, this data transmission technology could be used for other expendable marine-environment parametric measuring instruments such as an expendable bathythermograph and expendable conductivity temperature depth profiler.
Autors: Shu-Han Li;Qi-Sheng Zhang;Xiao Zhao;Sheng-Hui Liu;Xin-Yue Zhang;Zhen-Zhong Yuan;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Jan 2018, volume: 43, issue:1, pages: 66 - 71
Publisher: IEEE
 
» Dynamic Influence Networks for Rule-Based Models
Abstract:
We introduce the Dynamic Influence Network (DIN), a novel visual analytics technique for representing and analyzing rule-based models of protein-protein interaction networks. Rule-based modeling has proved instrumental in developing biological models that are concise, comprehensible, easily extensible, and that mitigate the combinatorial complexity of multi-state and multi-component biological molecules. Our technique visualizes the dynamics of these rules as they evolve over time. Using the data produced by KaSim, an open source stochastic simulator of rule-based models written in the Kappa language, DINs provide a node-link diagram that represents the influence that each rule has on the other rules. That is, rather than representing individual biological components or types, we instead represent the rules about them (as nodes) and the current influence of these rules (as links). Using our interactive DIN-Viz software tool, researchers are able to query this dynamic network to find meaningful patterns about biological processes, and to identify salient aspects of complex rule-based models. To evaluate the effectiveness of our approach, we investigate a simulation of a circadian clock model that illustrates the oscillatory behavior of the KaiC protein phosphorylation cycle.
Autors: Angus G. Forbes;Andrew Burks;Kristine Lee;Xing Li;Pierre Boutillier;Jean Krivine;Walter Fontana;
Appeared in: IEEE Transactions on Visualization and Computer Graphics
Publication date: Jan 2018, volume: 24, issue:1, pages: 184 - 194
Publisher: IEEE
 
» Dynamic Load Balancing Based on Constrained K-D Tree Decomposition for Parallel Particle Tracing
Abstract:
We propose a dynamically load-balanced algorithm for parallel particle tracing, which periodically attempts to evenly redistribute particles across processes based on k-d tree decomposition. Each process is assigned with (1) a statically partitioned, axis-aligned data block that partially overlaps with neighboring blocks in other processes and (2) a dynamically determined k-d tree leaf node that bounds the active particles for computation; the bounds of the k-d tree nodes are constrained by the geometries of data blocks. Given a certain degree of overlap between blocks, our method can balance the number of particles as much as possible. Compared with other load-balancing algorithms for parallel particle tracing, the proposed method does not require any preanalysis, does not use any heuristics based on flow features, does not make any assumptions about seed distribution, does not move any data blocks during the run, and does not need any master process for work redistribution. Based on a comprehensive performance study up to 8K processes on a Blue Gene/Q system, the proposed algorithm outperforms baseline approaches in both load balance and scalability on various flow visualization and analysis problems.
Autors: Jiang Zhang;Hanqi Guo;Fan Hong;Xiaoru Yuan;Tom Peterka;
Appeared in: IEEE Transactions on Visualization and Computer Graphics
Publication date: Jan 2018, volume: 24, issue:1, pages: 954 - 963
Publisher: IEEE
 
» Dynamic State Estimation With Model Uncertainties Using $H_infty$ Extended Kalman Filter
Abstract:
When implementing Kalman filters to track system dynamic state variables, the dynamical model is assumed to be accurate. However, this assumption may not hold true as power system dynamical model is subjected to various uncertainties, such as varying generator transient reactance in different operation conditions, uncertain inputs, or noise statistics. As a result, the performance of Kalman-type filters can be degraded significantly. To bound the influence of these uncertainties, this letter proposes an extended Kalman filter (HEKF) based on the robust control theory. An approach to tune the parameter of HEKF is presented as well. Numerical results on the IEEE 39-bus system demonstrate the effectiveness of the HEKF.
Autors: Junbo Zhao;
Appeared in: IEEE Transactions on Power Systems
Publication date: Jan 2018, volume: 33, issue:1, pages: 1099 - 1100
Publisher: IEEE
 
» EABS: An Event-Aware Backpressure Scheduling Scheme for Emergency Internet of Things
Abstract:
The backpressure scheduling scheme has been applied in Internet of Things, which can control the network congestion effectively and increase the network throughput. However, in large-scale Emergency Internet of Things (EIoT), emergency packets may exist because of the urgent events or situations. The traditional backpressure scheduling scheme will explore all the possible routes between the source and destination nodes that cause a superfluous long path for packets. Therefore, the end-to-end delay increases and the real-time performance of emergency packets cannot be guaranteed. To address this shortcoming, this paper proposes EABS, an event-aware backpressure scheduling scheme for EIoT. A backpressure queue model with emergency packets is first devised based on the analysis of the arrival process of different packets. Meanwhile, EABS combines the shortest path with backpressure scheme in the process of next-hop node selecting. The emergency packets are forwarded in the shortest path and avoid the network congestion according to the queue backlog difference. The extensive experiment results verify that EABS can reduce the average end-to-end delay and increase the average forwarding percentage. For the emergency packets, the real-time performance is guaranteed. Moreover, we compare EABS with two existing backpressure scheduling schemes, showing that EABS outperforms both of them.
Autors: Tie Qiu;Ruixuan Qiao;Dapeng Oliver Wu;
Appeared in: IEEE Transactions on Mobile Computing
Publication date: Jan 2018, volume: 17, issue:1, pages: 72 - 84
Publisher: IEEE
 
» EAPC: Energy-Aware Path Construction for Data Collection Using Mobile Sink in Wireless Sensor Networks
Abstract:
Data collection is one of the paramount concerns in wireless sensor networks. Many data collection algorithms have been proposed for collecting data in particular monitoring regions. However, the efficiency of the paths for such data collection can be improved. This paper proposes an energy-aware path construction (EAPC) algorithm, which selects an appropriate set of data collection points, constructs a data collection path, and collects data from the points burdened with data. EAPC is intended to prolong the network lifetime, it accounts for the path cost from its current data collection point to the next point and the forwarding load of each sensor node. Performance evaluation reveals that the proposed EAPC has more efficient performance than existing data collection mechanisms in terms of network lifetime, energy consumption, fairness index, and efficiency index.
Autors: Weimin Wen;Shenghui Zhao;Cuijuan Shang;Chih-Yung Chang;
Appeared in: IEEE Sensors Journal
Publication date: Jan 2018, volume: 18, issue:2, pages: 890 - 901
Publisher: IEEE
 
» EDFA Wavelength Dependent Gain Spectrum Measurement Using Weak Optical Probe Sampling
Abstract:
Wavelength dependent gain is a critical parameter in erbium-doped fiber amplifiers and is the primary determinant of the channel power divergence and excursions in optical transmission systems, each of which varies with channel loading in wavelength-division-multiplexed (WDM) systems. In an optical transmission system, measurements of the wavelength dependent gain between two locations can be used to obtain estimates of optical power excursions that occur in optical circuit switching. Non-intrusive sampling of just 10% of the WDM channel positions using weak probe signals achieves less than 0.15 dB error for the gain spectrum estimation of the amplifier with 5 dB tilt. In a two-span node-to-node network with a 3 dB peak-to-peak channel power difference, the weak probe approach further shows to provide less than 0.2 dB error in optical channel power excursion prediction for changes in channel loading.
Autors: Weiyang Mo;Shengxiang Zhu;Yao Li;Daniel C. Kilper;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jan 2018, volume: 30, issue:2, pages: 177 - 180
Publisher: IEEE
 
» Editorial
Abstract:
At its core, a technical publication represents a community or a community of communities that share an interest in solving commonly understood technical problems, often with an understanding of the nature of methods that must be invented. As communities go, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems (TCAD) represents a very diverse community spread across a large number of technical areas spanning very large scale integration (VLSI), CAD, circuits, embedded systems, formal methods, etc., and internationally spanning nearly all regions of the IEEE.
Autors: Rajesh K. Gupta;
Appeared in: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Publication date: Jan 2018, volume: 37, issue:1, pages: 1 - 2
Publisher: IEEE
 
» Editorial A New Beginning Within a Solid Tradition
Abstract:
Autors: A. Astolfi;
Appeared in: IEEE Transactions on Automatic Control
Publication date: Jan 2018, volume: 63, issue:1, pages: 1 - 2
Publisher: IEEE
 
» Editorial Addition of New Material After Peer Review
Abstract:
This editorial addresses a serious concern of author misconduct that must be addressed at the editorial level. The problem is not new, but the frequency of occurrences in the last few months has brought the matter to the forefront of our attention. We are talking about the many instances of authors adding new material to their papers after the peer-review process has been completed. To provide the background about the problem, when the paper under review has been recommended for publication by an Associate Editor, the peer-review process has been completed. In the decision letter, the authors are requested to submit a final version that will be sent to the IEEE for typesetting. The final version of the paper is checked carefully at the editorial office as a matter of quality control.
Autors: Mandar Chitre;N. Ross Chapman;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Jan 2018, volume: 43, issue:1, pages: 2 - 2
Publisher: IEEE
 
» Editorial from the New Editor in Chief
Abstract:
Presents the introductory editorial for this issue of the publication.
Autors: Nenad Medvidović;
Appeared in: IEEE Transactions on Software Engineering
Publication date: Jan 2018, volume: 44, issue:1, pages: 3 - 4
Publisher: IEEE
 
» Editorial Hello From Your New EIC
Abstract:
Presents the introductory editorial for this issue of the publication.
Autors: Mandar Chitre;
Appeared in: IEEE Journal of Oceanic Engineering
Publication date: Jan 2018, volume: 43, issue:1, pages: 1 - 1
Publisher: IEEE
 
» EdWordle: Consistency-Preserving Word Cloud Editing
Abstract:
We present EdWordle, a method for consistently editing word clouds. At its heart, EdWordle allows users to move and edit words while preserving the neighborhoods of other words. To do so, we combine a constrained rigid body simulation with a neighborhood-aware local Wordle algorithm to update the cloud and to create very compact layouts. The consistent and stable behavior of EdWordle enables users to create new forms of word clouds such as storytelling clouds in which the position of words is carefully edited. We compare our approach with state-of-the-art methods and show that we can improve user performance, user satisfaction, as well as the layout itself.
Autors: Yunhai Wang;Xiaowei Chu;Chen Bao;Lifeng Zhu;Oliver Deussen;Baoquan Chen;Michael Sedlmair;
Appeared in: IEEE Transactions on Visualization and Computer Graphics
Publication date: Jan 2018, volume: 24, issue:1, pages: 647 - 656
Publisher: IEEE
 
» EEG-Based Affect and Workload Recognition in a Virtual Driving Environment for ASD Intervention
Abstract:
Objective: To build group-level classification models capable of recognizing affective states and mental workload of individuals with autism spectrum disorder (ASD) during driving skill training. Methods: Twenty adolescents with ASD participated in a six-session virtual reality driving simulator-based experiment, during which their electroencephalogram (EEG) data were recorded alongside driving events and a therapist's rating of their affective states and mental workload. Five feature generation approaches including statistical features, fractal dimension features, higher order crossings (HOC)-based features, power features from frequency bands, and power features from bins () were applied to extract relevant features. Individual differences were removed with a two-step feature calibration method. Finally, binary classification results based on the k-nearest neighbors algorithm and univariate feature selection method were evaluated by leave-one-subject-out nested cross-validation to compare feature types and identify discriminative features. Results: The best classification results were achieved using power features from bins for engagement (0.95) and boredom (0.78), and HOC-based features for enjoyment (0.90), frustration (0.88), and workload (0.86). Conclusion: Offline EEG-based group-level classification models are feasible for recognizing binary low and high intensity of affect and workload of individuals with ASD in the context of driving. However, while promising the applicability of the models in an online adaptive driving task requires further development. Significance: The developed models provide a basis for an EEG-based passive brain computer interface system that has the potential to benefit individuals with ASD w- th an affect- and workload-based individualized driving skill training intervention.
Autors: Jing Fan;Joshua W. Wade;Alexandra P. Key;Zachary E. Warren;Nilanjan Sarkar;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Jan 2018, volume: 65, issue:1, pages: 43 - 51
Publisher: IEEE
 
» Effect of Nonlinear Screening on a Complex Plasma Phase State
Abstract:
Applicability limit of the well-known phase diagram of dusty plasmas in – plane ( is structural parameter and is parameter of Coulomb nonideality) is under discussion. Existence of extensive domains with violation of plasma thermodynamic stability conditions (i.e., with negative isothermal compressibility) was also claimed if one uses well-known nonideal equations of state by (Hamaguchi S. et al., Phys. Rev. E, 1997) and (Khrapak S. et al., Phys. Rev. E, 2014). This paper is devoted to analysis of a range of applicability for basic assumption in Hamaguchi’s phase diagram, i.e., linearized (Debye) screening of macroions by microions, which leads to the Yukawa form for effective interactions between macroions. Parameters of nonlinear screening for macroions were calculated within differential Poisson–Boltzmann equation. Two effects were revealed as a result of such calculations: 1) decomposition of all microions onto two subclasses, free and bound ones, and 2) significant reduction of effective charge of initial bare macroion Z under nonlinear screening by small high-density envelope of bound ions. This effect leads to a renormalization of initial and into and (, ). The main physical assumption is phase states of complex plasma under nonlinear screening, which are still the same as on the initial phase diagram, but in – plane instead of – one. Corresponding calculated shifts of phase states are discussed and illustrated.
Autors: Inna A. Martynova;Igor L. Iosilevskiy;Andrey A. Shagayda;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Jan 2018, volume: 46, issue:1, pages: 14 - 18
Publisher: IEEE
 
» Effect of Precursor Concentration on Structural, Morphological, and Optical Properties of ZnO Thin-Filmed Sensor for Ethanol Detection
Abstract:
Zinc Oxide (ZnO) nanostructured thin films with precursor concentration variation of 0.025 M (1Z), 0.075 M (2Z), and 0.125 M (3Z) were fabricated on fluorine-doped tin oxide glass substrates using a simple hydrothermal technique. X-ray diffraction confirmed Wurtzite hexagonal structure of ZnO. Changes in the lattice constant in accordance with the variation in precursor concentrations were observed. It was manifested by bond length, unit cell volume, micro strain, and dislocation density. Optical band gap, diameter, and photoluminance peak intensity ratios of each sensor were determined. The field emitting scanning electron microscope image of 1Z, 2Z, and 3Z sensors revealed massive changes in the morphology of the nanostructures grown on the substrate. The ethanol sensing behavior of ZnO thin-film sensors toward different ethanol concentration under varied operating temperatures were experimented and recorded. The results demonstrated highest sensitivity of 58.5% by 1Z sensor with response and recovery time of 40 and 45 s, respectively. Particularly, 2Z sensor outperformed other two sensors with a fast response time and quick recovery time of 25 and 15 s, respectively, with moderate sensitivity.
Autors: Sudha Murugesan;Radha Shankararajan;Kirubaveni Savarimuthu;Kiruthika Ramany;Govindaraj Rajamanickam;Santhosh Narendhiran;Ramasamy Perumalsamy;
Appeared in: IEEE Transactions on Nanotechnology
Publication date: Jan 2018, volume: 17, issue:1, pages: 169 - 176
Publisher: IEEE
 
» Effect of Silicon Content on Iron Loss and Magnetic Domain Structure of Grain-Oriented Electrical Steel Sheet
Abstract:
Increasing the silicon content in non-grain-oriented (NO) electrical steel sheets is known to decrease iron loss by changing electrical resistivity and magnetostriction behavior. However, few studies on the effect of high silicon contents in grain-oriented (GO) electrical steel have been reported. One of the major differences in the iron loss of GO and NO is that excess eddy current loss, which has a strong relationship with the magnetic domain structure, is more dominant in total iron loss in GO. In this paper, high silicon GO was prepared by the CVD siliconizing method, which has the advantage that the silicon content can be changed without changing the crystal grain size and crystallographic texture of the specimen. It was found that iron loss was reduced as the silicon content was increased, and 6.5 mass% silicon steel showed about half the hysteresis loss of conventional 3 mass% silicon steel, but the eddy current loss in 6.5 mass% silicon steel was equivalent to or slightly larger than that in 3 mass% silicon steel. Magnetic domain observation and calculations suggested that this difference was a result of coarsening of the magnetic domains in the high silicon steel.
Autors: S. Takajo;T. Hiratani;T. Okubo;Y. Oda;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jan 2018, volume: 54, issue:1, pages: 1 - 6
Publisher: IEEE
 
» Effect of the Deformation State on the Response of a Flexible H2S Sensor Based on a Ph5T2 Single-Crystal Transistor
Abstract:
Flexible H2S sensors were fabricated based on ultrathin dinaphtho [3, 4-d:3’, 4’-d’] benzo [1, 2-b:4, 5b’] dithiophene (Ph5T2) single-crystal organic field-effect transistors, and response performances at different deformation states were investigated. The flexible devices exhibited strikingly different sensing behaviors under different deformation states toward H2S at room temperature. In a tensile state with mm, the flexible sensor presented an unprecedented response as high as 400% at 1 ppm H2S, which is almost one order of magnitude higher than the response in a flat state and surpasses all reported flexible H2S sensors. Such a surprising improvement provides an effective way to enhance the response of gas sensors and shows the potential advantage of using flexible sensors in tensile states.
Autors: Kunpeng Tang;Zhiqi Song;Qingxin Tang;Hongkun Tian;Yanhong Tong;Yichun Liu;
Appeared in: IEEE Electron Device Letters
Publication date: Jan 2018, volume: 39, issue:1, pages: 119 - 122
Publisher: IEEE
 
» Effective Uyghur Language Text Detection in Complex Background Images for Traffic Prompt Identification
Abstract:
Text detection in complex background images is a challenging task for intelligent vehicles. Actually, almost all the widely-used systems focus on commonly used languages while for some minority languages, such as the Uyghur language, text detection is paid less attention. In this paper, we propose an effective Uyghur language text detection system in complex background images. First, a new channel-enhanced maximally stable extremal regions (MSERs) algorithm is put forward to detect component candidates. Second, a two-layer filtering mechanism is designed to remove most non-character regions. Third, the remaining component regions are connected into short chains, and the short chains are extended by a novel extension algorithm to connect the missed MSERs. Finally, a two-layer chain elimination filter is proposed to prune the non-text chains. To evaluate the system, we build a new data set by various Uyghur texts with complex backgrounds. Extensive experimental comparisons show that our system is obviously effective for Uyghur language text detection in complex background images. The F-measure is 85%, which is much better than the state-of-the-art performance of 75.5%.
Autors: Chenggang Yan;Hongtao Xie;Shun Liu;Jian Yin;Yongdong Zhang;Qionghai Dai;
Appeared in: IEEE Transactions on Intelligent Transportation Systems
Publication date: Jan 2018, volume: 19, issue:1, pages: 220 - 229
Publisher: IEEE
 
» Effects of Continuous Kinaesthetic Feedback Based on Tendon Vibration on Motor Imagery BCI Performance
Abstract:
Background and objectives: Feedback plays a crucial role for using brain computer interface systems. This paper proposes the use of vibration-evoked kinaesthetic illusions as part of a novel multisensory feedback for a motor imagery (MI)-based BCI and investigates its contributions in terms of BCI performance and electroencephalographic (EEG) correlates. Methods: sixteen subjects performed two different right arm MI-BCI sessions: with the visual feedback only and with both visual and vibration-evoked kinaesthetic feedback, conveyed by the stimulation of the biceps brachi tendon. In both conditions, the sensory feedback was driven by the MI-BCI. The rich and more natural multisensory feedback was expected to facilitate the execution of MI, and thus to improve the performance of the BCI. The EEG correlates of the proposed feedback were also investigated with and without the performing of MI. Results and Conclusions: the contribution of vibration-evoked kinaesthetic feedback led to statistically higher BCI performance (Anova, F(1,14) = 18.1, p < .01) and more stable EEG event-related-desynchronization. Obtained results suggest promising application of the proposed method in neuro-rehabilitation scenarios: the advantage of an improved usability could make the MI-BCIs more applicable for those patients having difficulties in performing kinaesthetic imagery.
Autors: Michele Barsotti;Daniele Leonardis;Nicola Vanello;Massimo Bergamasco;Antonio Frisoli;
Appeared in: IEEE Transactions on Neural Systems and Rehabilitation Engineering
Publication date: Jan 2018, volume: 26, issue:1, pages: 105 - 114
Publisher: IEEE
 
» Effects of Stacked Mo–Ti/Cu Source and Drain Electrodes on the Performance of Amorphous In–Ga–Zn-O Thin-Film Transistors
Abstract:
In this letter, the performance of amorphous In–Ga–Zn-O (a-IGZO) thin-film transistors (TFTs) is investigated using the stacked Mo–Ti/Cu source (S) and drain (D) electrodes. The test samples A and B of the a-IGZO TFT have interlayers with Mo/Ti ratios of 2.29 and 1.15, respectively, for the SD electrodes, and each has a core layer of Cu stacked on the top of the interlayers. They were fabricated and measured to compare their performance in terms of the transfer characteristic and mobility. The measurement results showed that the sample B with a lower Mo/Ti ratio exhibited better performance than the sample A: higher field-effect mobility by 4.4 cm2/V-s, higher saturation mobility by 3.2 cm2/V-s, smaller sub-threshold slope by 0.91 V/decade, and lower threshold voltage by 1.4 V. In addition, the material properties of samples A and B were obtained using the line scan of the energy dispersive spectroscopy and analyzed with technology computer-aided design simulation. As a result, the performance of a-IGZO TFTs can be optimized by tuning the Mo/Ti ratios of the interlayer in the stacked SD electrodes.
Autors: Lee-Young Kim;Oh-Kyong Kwon;
Appeared in: IEEE Electron Device Letters
Publication date: Jan 2018, volume: 39, issue:1, pages: 43 - 46
Publisher: IEEE
 

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