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  Subjects -> ELECTRONICS (Total: 179 journals)
Showing 1 - 200 of 277 Journals sorted alphabetically
Acta Electronica Malaysia     Open Access  
Advances in Biosensors and Bioelectronics     Open Access   (Followers: 7)
Advances in Electrical and Electronic Engineering     Open Access   (Followers: 5)
Advances in Electronics     Open Access   (Followers: 78)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Microelectronic Engineering     Open Access   (Followers: 13)
Advances in Power Electronics     Open Access   (Followers: 33)
Advancing Microelectronics     Hybrid Journal  
Aerospace and Electronic Systems, IEEE Transactions on     Hybrid Journal   (Followers: 315)
American Journal of Electrical and Electronic Engineering     Open Access   (Followers: 24)
Annals of Telecommunications     Hybrid Journal   (Followers: 9)
APSIPA Transactions on Signal and Information Processing     Open Access   (Followers: 9)
Archives of Electrical Engineering     Open Access   (Followers: 13)
Autonomous Mental Development, IEEE Transactions on     Hybrid Journal   (Followers: 8)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 28)
Bioelectronics in Medicine     Hybrid Journal  
Biomedical Engineering, IEEE Reviews in     Full-text available via subscription   (Followers: 19)
Biomedical Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 36)
Biomedical Instrumentation & Technology     Hybrid Journal   (Followers: 6)
Broadcasting, IEEE Transactions on     Hybrid Journal   (Followers: 12)
BULLETIN of National Technical University of Ukraine. Series RADIOTECHNIQUE. RADIOAPPARATUS BUILDING     Open Access   (Followers: 1)
Bulletin of the Polish Academy of Sciences : Technical Sciences     Open Access   (Followers: 1)
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 47)
China Communications     Full-text available via subscription   (Followers: 8)
Chinese Journal of Electronics     Hybrid Journal  
Circuits and Systems     Open Access   (Followers: 15)
Consumer Electronics Times     Open Access   (Followers: 5)
Control Systems     Hybrid Journal   (Followers: 269)
Edu Elektrika Journal     Open Access   (Followers: 1)
Electrica     Open Access  
Electronic Design     Partially Free   (Followers: 105)
Electronic Markets     Hybrid Journal   (Followers: 7)
Electronic Materials Letters     Hybrid Journal   (Followers: 4)
Electronics     Open Access   (Followers: 86)
Electronics and Communications in Japan     Hybrid Journal   (Followers: 10)
Electronics For You     Partially Free   (Followers: 92)
Electronics Letters     Hybrid Journal   (Followers: 26)
Elkha : Jurnal Teknik Elektro     Open Access  
Embedded Systems Letters, IEEE     Hybrid Journal   (Followers: 51)
Energy Harvesting and Systems     Hybrid Journal   (Followers: 4)
Energy Storage Materials     Full-text available via subscription   (Followers: 3)
EPJ Quantum Technology     Open Access  
EURASIP Journal on Embedded Systems     Open Access   (Followers: 11)
Facta Universitatis, Series : Electronics and Energetics     Open Access  
Foundations and Trends® in Communications and Information Theory     Full-text available via subscription   (Followers: 6)
Foundations and Trends® in Signal Processing     Full-text available via subscription   (Followers: 10)
Frequenz     Hybrid Journal   (Followers: 1)
Frontiers of Optoelectronics     Hybrid Journal   (Followers: 1)
Geoscience and Remote Sensing, IEEE Transactions on     Hybrid Journal   (Followers: 191)
Haptics, IEEE Transactions on     Hybrid Journal   (Followers: 4)
IACR Transactions on Symmetric Cryptology     Open Access  
IEEE Antennas and Propagation Magazine     Hybrid Journal   (Followers: 97)
IEEE Antennas and Wireless Propagation Letters     Hybrid Journal   (Followers: 77)
IEEE Journal of Emerging and Selected Topics in Power Electronics     Hybrid Journal   (Followers: 46)
IEEE Journal of the Electron Devices Society     Open Access   (Followers: 9)
IEEE Journal on Exploratory Solid-State Computational Devices and Circuits     Hybrid Journal   (Followers: 1)
IEEE Power Electronics Magazine     Full-text available via subscription   (Followers: 66)
IEEE Transactions on Antennas and Propagation     Full-text available via subscription   (Followers: 70)
IEEE Transactions on Automatic Control     Hybrid Journal   (Followers: 56)
IEEE Transactions on Circuits and Systems for Video Technology     Hybrid Journal   (Followers: 19)
IEEE Transactions on Consumer Electronics     Hybrid Journal   (Followers: 40)
IEEE Transactions on Electron Devices     Hybrid Journal   (Followers: 19)
IEEE Transactions on Information Theory     Hybrid Journal   (Followers: 26)
IEEE Transactions on Power Electronics     Hybrid Journal   (Followers: 71)
IEEE Transactions on Signal and Information Processing over Networks     Full-text available via subscription   (Followers: 12)
IEICE - Transactions on Electronics     Full-text available via subscription   (Followers: 12)
IEICE - Transactions on Information and Systems     Full-text available via subscription   (Followers: 5)
IET Cyber-Physical Systems : Theory & Applications     Open Access   (Followers: 1)
IET Microwaves, Antennas & Propagation     Hybrid Journal   (Followers: 35)
IET Nanodielectrics     Open Access  
IET Power Electronics     Hybrid Journal   (Followers: 46)
IET Smart Grid     Open Access  
IET Wireless Sensor Systems     Hybrid Journal   (Followers: 18)
IETE Journal of Education     Open Access   (Followers: 4)
IETE Journal of Research     Open Access   (Followers: 11)
IETE Technical Review     Open Access   (Followers: 13)
IJEIS (Indonesian Journal of Electronics and Instrumentation Systems)     Open Access   (Followers: 3)
Industrial Electronics, IEEE Transactions on     Hybrid Journal   (Followers: 58)
Industry Applications, IEEE Transactions on     Hybrid Journal   (Followers: 24)
Informatik-Spektrum     Hybrid Journal   (Followers: 2)
Instabilities in Silicon Devices     Full-text available via subscription   (Followers: 1)
Intelligent Transportation Systems Magazine, IEEE     Full-text available via subscription   (Followers: 13)
International Journal of Advanced Research in Computer Science and Electronics Engineering     Open Access   (Followers: 18)
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems     Open Access   (Followers: 10)
International Journal of Antennas and Propagation     Open Access   (Followers: 11)
International Journal of Applied Electronics in Physics & Robotics     Open Access   (Followers: 5)
International Journal of Computational Vision and Robotics     Hybrid Journal   (Followers: 6)
International Journal of Control     Hybrid Journal   (Followers: 12)
International Journal of Electronics     Hybrid Journal   (Followers: 7)
International Journal of Electronics and Telecommunications     Open Access   (Followers: 13)
International Journal of Granular Computing, Rough Sets and Intelligent Systems     Hybrid Journal   (Followers: 2)
International Journal of High Speed Electronics and Systems     Hybrid Journal  
International Journal of Image, Graphics and Signal Processing     Open Access   (Followers: 14)
International Journal of Microwave and Wireless Technologies     Hybrid Journal   (Followers: 8)
International Journal of Nano Devices, Sensors and Systems     Open Access   (Followers: 12)
International Journal of Nanoscience     Hybrid Journal   (Followers: 1)
International Journal of Numerical Modelling: Electronic Networks, Devices and Fields     Hybrid Journal   (Followers: 4)
International Journal of Power Electronics     Hybrid Journal   (Followers: 24)
International Journal of Review in Electronics & Communication Engineering     Open Access   (Followers: 4)
International Journal of Sensors, Wireless Communications and Control     Hybrid Journal   (Followers: 10)
International Journal of Systems, Control and Communications     Hybrid Journal   (Followers: 4)
International Journal of Wireless and Microwave Technologies     Open Access   (Followers: 6)
International Transaction of Electrical and Computer Engineers System     Open Access   (Followers: 2)
JAREE (Journal on Advanced Research in Electrical Engineering)     Open Access  
Journal of Biosensors & Bioelectronics     Open Access   (Followers: 3)
Journal of Advanced Dielectrics     Open Access   (Followers: 1)
Journal of Artificial Intelligence     Open Access   (Followers: 10)
Journal of Circuits, Systems, and Computers     Hybrid Journal   (Followers: 4)
Journal of Computational Intelligence and Electronic Systems     Full-text available via subscription   (Followers: 1)
Journal of Electrical and Electronics Engineering Research     Open Access   (Followers: 24)
Journal of Electrical Bioimpedance     Open Access   (Followers: 2)
Journal of Electrical Engineering & Electronic Technology     Hybrid Journal   (Followers: 7)
Journal of Electrical, Electronics and Informatics     Open Access  
Journal of Electromagnetic Analysis and Applications     Open Access   (Followers: 7)
Journal of Electromagnetic Waves and Applications     Hybrid Journal   (Followers: 8)
Journal of Electronic Design Technology     Full-text available via subscription   (Followers: 6)
Journal of Electronics (China)     Hybrid Journal   (Followers: 4)
Journal of Energy Storage     Full-text available via subscription   (Followers: 4)
Journal of Engineered Fibers and Fabrics     Open Access  
Journal of Field Robotics     Hybrid Journal   (Followers: 2)
Journal of Guidance, Control, and Dynamics     Hybrid Journal   (Followers: 168)
Journal of Information and Telecommunication     Open Access   (Followers: 1)
Journal of Intelligent Procedures in Electrical Technology     Open Access   (Followers: 3)
Journal of Low Power Electronics     Full-text available via subscription   (Followers: 7)
Journal of Low Power Electronics and Applications     Open Access   (Followers: 9)
Journal of Microelectronics and Electronic Packaging     Hybrid Journal  
Journal of Microwave Power and Electromagnetic Energy     Hybrid Journal  
Journal of Microwaves, Optoelectronics and Electromagnetic Applications     Open Access   (Followers: 10)
Journal of Nuclear Cardiology     Hybrid Journal  
Journal of Optoelectronics Engineering     Open Access   (Followers: 4)
Journal of Physics B: Atomic, Molecular and Optical Physics     Hybrid Journal   (Followers: 28)
Journal of Power Electronics & Power Systems     Full-text available via subscription   (Followers: 11)
Journal of Semiconductors     Full-text available via subscription   (Followers: 5)
Journal of Sensors     Open Access   (Followers: 26)
Journal of Signal and Information Processing     Open Access   (Followers: 9)
Jurnal Rekayasa Elektrika     Open Access  
Jurnal Teknik Elektro     Open Access  
Jurnal Teknologi Elektro     Open Access  
Kinetik : Game Technology, Information System, Computer Network, Computing, Electronics, and Control     Open Access  
Learning Technologies, IEEE Transactions on     Hybrid Journal   (Followers: 12)
Magnetics Letters, IEEE     Hybrid Journal   (Followers: 7)
Majalah Ilmiah Teknologi Elektro : Journal of Electrical Technology     Open Access   (Followers: 2)
Metrology and Measurement Systems     Open Access   (Followers: 5)
Microelectronics and Solid State Electronics     Open Access   (Followers: 18)
Nanotechnology Magazine, IEEE     Full-text available via subscription   (Followers: 33)
Nanotechnology, Science and Applications     Open Access   (Followers: 6)
Nature Electronics     Hybrid Journal  
Networks: an International Journal     Hybrid Journal   (Followers: 5)
Open Electrical & Electronic Engineering Journal     Open Access  
Open Journal of Antennas and Propagation     Open Access   (Followers: 8)
Optical Communications and Networking, IEEE/OSA Journal of     Full-text available via subscription   (Followers: 15)
Paladyn. Journal of Behavioral Robotics     Open Access   (Followers: 1)
Power Electronics and Drives     Open Access   (Followers: 1)
Problemy Peredachi Informatsii     Full-text available via subscription  
Progress in Quantum Electronics     Full-text available via subscription   (Followers: 7)
Pulse     Full-text available via subscription   (Followers: 5)
Radiophysics and Quantum Electronics     Hybrid Journal   (Followers: 2)
Recent Advances in Communications and Networking Technology     Hybrid Journal   (Followers: 3)
Recent Advances in Electrical & Electronic Engineering     Hybrid Journal   (Followers: 9)
Research & Reviews : Journal of Embedded System & Applications     Full-text available via subscription   (Followers: 5)
Security and Communication Networks     Hybrid Journal   (Followers: 2)
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of     Hybrid Journal   (Followers: 53)
Semiconductors and Semimetals     Full-text available via subscription   (Followers: 1)
Sensing and Imaging : An International Journal     Hybrid Journal   (Followers: 2)
Services Computing, IEEE Transactions on     Hybrid Journal   (Followers: 4)
Software Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 75)
Solid-State Circuits Magazine, IEEE     Hybrid Journal   (Followers: 13)
Solid-State Electronics     Hybrid Journal   (Followers: 9)
Superconductor Science and Technology     Hybrid Journal   (Followers: 2)
Synthesis Lectures on Power Electronics     Full-text available via subscription   (Followers: 3)
Technical Report Electronics and Computer Engineering     Open Access  
TELE     Open Access  
Telematique     Open Access  
TELKOMNIKA (Telecommunication, Computing, Electronics and Control)     Open Access   (Followers: 9)
Universal Journal of Electrical and Electronic Engineering     Open Access   (Followers: 6)
Visión Electrónica : algo más que un estado sólido     Open Access   (Followers: 1)
Wireless and Mobile Technologies     Open Access   (Followers: 6)
Wireless Power Transfer     Full-text available via subscription   (Followers: 4)
Women in Engineering Magazine, IEEE     Full-text available via subscription   (Followers: 11)
Електротехніка і Електромеханіка     Open Access  

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Journal Cover
Electronics
Journal Prestige (SJR): 0.548
Citation Impact (citeScore): 3
Number of Followers: 86  

  This is an Open Access Journal Open Access journal
ISSN (Print) 2079-9292
Published by MDPI Homepage  [215 journals]
  • Electronics, Vol. 8, Pages 370: Variable Sampling Rate based Active
           Disturbance Control for a Marine Diesel Engine

    • Authors: Runzhi Wang, Xuemin Li, Yufei Liu, Qadeer Ahemd, Yunlong Yang, Chunyue Feng, Xiuzhen Ma
      First page: 370
      Abstract: In this paper, in order to handle the high nonlinearity and the sophisticated disturbance in marine engines, a variable sampling rate based active disturbance rejection controller is developed for engine speed control. In the proposed method, the Active Disturbance Rejection Control (ADRC) is designed with the consideration of the practical application in engine speed control that is known as the Crank-angle (CA) based or event-based sampling and control, which means the sampling interval varies with the engine speed. Such a problem has not been discussed in any previous study regarding the application of ADRC in engine control. To this end, this paper discusses the convergence of the variable sampling rate based Extended State Observer (ESO), as well as its parameters that guarantee stability. To verify the proposed control scheme more properly, a cycle-detailed hybrid nonlinear engine model is employed. Finally, simulations are carried out on the Hardware-in-the-loop (HIL) system to assess the superiority of the proposed strategy. The comparative results with a Fuzzy-Proportional-Integral-Derivative (PID) controller demonstrate that the proposed control scheme has better adaptation to engine speed, load disturbances, and stronger robustness towards model uncertainties, which indicates a promising reduction of time and burden for calibrating the controller. It also proved that the proposed CA based ADRC by variable sampling rate method outperforms the general fixed sampling rate ADRC, which is widely used in previous works. Moreover, the successful application of the proposed algorithm via CA based strategy in a real Engine Control Unit (ECU) indicates its huge potential in practical engine control.
      Citation: Electronics
      PubDate: 2019-03-27
      DOI: 10.3390/electronics8040370
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 371: An Efficient Streaming Accelerator for Low
           Bit-Width Convolutional Neural Networks

    • Authors: Qinyu Chen, Yuxiang Fu, Wenqing Song, Kaifeng Cheng, Zhonghai Lu, Chuan Zhang, Li Li
      First page: 371
      Abstract: Convolutional Neural Networks (CNNs) have been widely applied in various fields, such as image recognition, speech processing, as well as in many big-data analysis tasks. However, their large size and intensive computation hinder their deployment in hardware, especially on the embedded systems with stringent latency, power, and area requirements. To address this issue, low bit-width CNNs are proposed as a highly competitive candidate. In this paper, we propose an efficient, scalable accelerator for low bit-width CNNs based on a parallel streaming architecture. With a novel coarse grain task partitioning (CGTP) strategy, the proposed accelerator with heterogeneous computing units, supporting multi-pattern dataflows, can nearly double the throughput for various CNN models on average. Besides, a hardware-friendly algorithm is proposed to simplify the activation and quantification process, which can reduce the power dissipation and area overhead. Based on the optimized algorithm, an efficient reconfigurable three-stage activation-quantification-pooling (AQP) unit with the low power staged blocking strategy is developed, which can process activation, quantification, and max-pooling operations simultaneously. Moreover, an interleaving memory scheduling scheme is proposed to well support the streaming architecture. The accelerator is implemented with TSMC 40 nm technology with a core size of 0.17 mm 2 . It can achieve 7.03 TOPS/W energy efficiency and 4.14 TOPS/mm 2 area efficiency at 100.1 mW, which makes it a promising design for the embedded devices.
      Citation: Electronics
      PubDate: 2019-03-27
      DOI: 10.3390/electronics8040371
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 372: An Efficient Pilot Assignment Scheme for
           Addressing Pilot Contamination in Multicell Massive MIMO Systems

    • Authors: Ahmed S. Al-hubaishi, Nor Kamariah Noordin, Aduwati Sali, Shamala Subramaniam, Ali Mohammed Mansoor
      First page: 372
      Abstract: The reuse of the same pilot group across cells to address bandwidth limitations in a network has resulted in pilot contamination. This causes severe inter-cell interference at the targeted cell. Pilot contamination is associated with multicell massive multiple-input multiple-output (MIMO) systems which degrades the system performance even when extra arrays of antennas are added to the network. In this paper, we propose an efficient pilot assignment (EPA) scheme to address this issue by maximizing the minimum uplink rate of the target cell’s users. To achieve this, we exploit the large-scale characteristics of the fading channel to minimize the amount of outgoing inter-cell interference at the target cell. Results from the simulation show that the EPA scheme outperforms both the conventional and the smart pilot assignment (SPA) schemes by reducing the effect of inter-cell interference. These results, show that the EPA scheme has significantly improved the system performance in terms of achievable uplink rate and cumulative distribution function (CDF) for both signal-to-interference-plus-noise ratio (SINR), and uplink rate.
      Citation: Electronics
      PubDate: 2019-03-27
      DOI: 10.3390/electronics8040372
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 373: Impact of Polarization Distortions on
           

    • Authors: Qiaoling Liu, Chen Pang, Yongzhen Li, Xuesong Wang
      First page: 373
      Abstract: In this paper, the impact of several polarization distortions on geometrical structure retrieval of man-made targets in inverse synthetic aperture radar (ISAR) images is assessed. For polarimetric ISAR, the polarization distortions are usually composed of crosstalk and channel imbalance. For non-stationary targets, a residual phase error exists between two columns of the scattering matrix in the alternate transmission and simultaneous reception (ATSR) mode, especially when the radar frequency is high. These two kinds of distortions have varying influences on different targets, as well as different decomposition methods. Some theoretical derivations and numerical analyses are given to reveal the impact of these distortions on Cameron decomposition. To evaluate the impact of these distortions on geometrical structure retrieval, we use the numerical results and real data of an unmanned aerial vehicle (UAV) called Frontier to perform error analysis of both the decomposition and the retrieved size of the designated structures of the UAV. Some numerical evaluations were conducted from the perspective of system design, and these results can be useful for the practical radar system.
      Citation: Electronics
      PubDate: 2019-03-27
      DOI: 10.3390/electronics8040373
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 374: Optimal Image-Based Guidance of
           Mobile Manipulators using Direct Visual Servoing

    • Authors: Belmonte, Ramón, Pomares, Garcia, Jara
      First page: 374
      Abstract: This paper presents a direct image-based controller to perform the guidance of a mobilemanipulator using image-based control. An eye-in-hand camera is employed to perform theguidance of a mobile differential platform with a seven degrees-of-freedom robot arm. Thepresented approach is based on an optimal control framework and it is employed to control mobilemanipulators during the tracking of image trajectories taking into account robot dynamics. Thedirect approach allows us to take both the manipulator and base dynamics into account. Theproposed image-based controllers consider the optimization of the motor signals sent to the mobilemanipulator during the tracking of image trajectories by minimizing the control force and torque.As the results show, the proposed direct visual servoing system uses the eye-in-hand cameraimages for concurrently controlling both the base platform and robot arm. The use of the optimalframework allows us to derive different visual controllers with different dynamical behaviorsduring the tracking of image trajectories.
      Citation: Electronics
      PubDate: 2019-03-27
      DOI: 10.3390/electronics8040374
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 375: Indoor Positioning System: A New Approach
           Based on LSTM and Two Stage Activity Classification

    • Authors: Ghulam Hussain, Muhammad Shahid Jabbar, Jun-Dong Cho, Sangmin Bae
      First page: 375
      Abstract: The number of studies on the development of indoor positioning systems has increased recently due to the growing demands of the various location-based services. Inertial sensors available in commercial smartphones play an important role in indoor localization and navigation owing to their highly accurate localization performance. In this study, the inertial sensors of a smartphone, which generate distinct patterns for physical activities and action units (AUs), are employed to localize a target in an indoor environment. These AUs, (such as a left turn, right turn, normal step, short step, or long step), help to accurately estimate the indoor location of a target. By taking advantage of sophisticated deep learning algorithms, we propose a novel approach for indoor navigation based on long short-term memory (LSTM). The LSTM accurately recognizes physical activities and related AUs by automatically extracting the efficient features from the distinct patterns of the input data. Experiment results show that LSTM provides a significant improvement in the indoor positioning performance through the recognition task. The proposed system achieves a better localization performance than the trivial fingerprinting method, with an average error of 0.782 m in an indoor area of 128.6 m2. Additionally, the proposed system exhibited robust performance by excluding the abnormal activity from the pedestrian activities.
      Citation: Electronics
      PubDate: 2019-03-28
      DOI: 10.3390/electronics8040375
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 376: Innovative Technologies and Services for
           Smart Cities

    • Authors: Subhas Chandra Mukhopadhyay, Tarikul Islam
      First page: 376
      Abstract: Smart cities represent a multidiscipline field continuously evolved by the advancement of sensor-based information technology and communication technology [...]
      Citation: Electronics
      PubDate: 2019-03-28
      DOI: 10.3390/electronics8040376
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 377: Comparison of MOCVD and MBE Regrowth for
           CAVET Fabrication

    • Authors: Simon Kotzea, Wiebke Witte, Birte-Julia Godejohann, Mathias Marx, Michael Heuken, Holger Kalisch, Rolf Aidam, Andrei Vescan
      First page: 377
      Abstract: In this paper, we demonstrate the fabrication of current aperture vertical electron transistors (CAVET) realized with two different epitaxial growth methods. Templates with a p-GaN current blocking layer (CBL) were deposited by metal organic chemical vapor deposition (MOCVD). Channel and barrier layers were then regrown by either molecular beam epitaxy (MBE) or MOCVD. Scanning electron microscope (SEM) images and atomic force microscope (AFM) height profiles are used to identify the different regrowth mechanisms. We show that an AlN interlayer below the channel layer was able to reduce Mg diffusion during the high temperature MOCVD regrowth process. For the low-temperature MBE regrowth, Mg diffusion was successfully suppressed. CAVET were realized on the various samples. The devices suffer from high leakage currents, thus further regrowth optimization is needed.
      Citation: Electronics
      PubDate: 2019-03-28
      DOI: 10.3390/electronics8040377
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 378: Disturbance and Signal Filter for Power
           Line Communication

    • Authors: Krzysztof Bernacki, Dominik Wybrańczyk, Marcin Zygmanowski, Andrzej Latko, Jarosław Michalak, Zbigniew Rymarski
      First page: 378
      Abstract: Today, to use home automation, intelligent home controls or remote controls in the office, electronic equipment is moving away from wireless communication in favor of Power Line Communication (PLC). In the standard PLC solutions, the corrections that result from error transmissions are based on complex digital modulation methods and algorithms for validating the transmitted data without paying attention to the causes of the errors. This article focuses on the implementation of a filtering system for interference and signals in the 120–150 kHz band (CENELEC band C), which is injected into the network by transmitters. Such a filter separates the desired signal from the interference that is occurring in the network, which can result in communication errors. Moreover, when used properly, the filter can be used as a subsystem separation element. The paper presents the requirements, design, construction, simulation and test results that were obtained under actual operating conditions. It is possible to use less complex methods for correcting errors in transmission signals and to guarantee an improvement in the transmission rate using the proposed filter system.
      Citation: Electronics
      PubDate: 2019-03-28
      DOI: 10.3390/electronics8040378
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 379: Beam Scanning Capabilities of a 3D-Printed
           Perforated Dielectric Transmitarray

    • Authors: Andrea Massaccesi, Gianluca Dassano, Paola Pirinoli
      First page: 379
      Abstract: In this paper, the design of a beam scanning, 3D-printed dielectric Transmitarray (TA) working in Ka-band is discussed. Thanks to the use of an innovative three-layer dielectric unit-cell that exploits tapered sections to enhance the bandwidth, a 50 × 50 elements transmitarray with improved scanning capabilities and wideband behavior has been designed and experimentally validated. The measured radiation performances over a scanning coverage of ±27 ∘ shown a variation of the gain lower than 2.9 dB and a 1-dB bandwidth in any case higher than 23%. The promising results suggest that the proposed TA technology is a valid alternative to realize a passive multibeam antenna, with the additional advantage that it can be easily manufactured using 3D-printing techniques.
      Citation: Electronics
      PubDate: 2019-03-28
      DOI: 10.3390/electronics8040379
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 380: Analysis Methodology for Evaluation of
           Time-Delay Impact on Network-Based System for Droop-Controlled AC
           Microgrid

    • Authors: Yao Zhang
      First page: 380
      Abstract: Potential performance improvements can be obtained by introducing communication techniques in the power electronic systems. However, network-induced time-delay could bring negative consequences of degrading performance or destabilizing the system in many cases. To investigate and handle the impacts of time-delay, a suit of analytical methodology is proposed, where both delay-insensitive and delay-sensitive control strategies of network-based system have their theoretical methods and different problem-solving paths. The former is to predict the maximum allowable boundaries of time-delay for releasing more network resources, and the latter is to use the controller-altering method for changing its original instability, respectively. The proposed methodology is concretely applied in network-based system of droop-controlled AC (Alternating Current) microgrid in islanded mode. Two different current-sharing strategies are mathematically analyzed and given to verify their validity. Experimental results also show the effectiveness of the proposed methodology in droop-controlled AC microgrid system, which provides theoretical guidance on how to use network-based control for the other power electronic systems.
      Citation: Electronics
      PubDate: 2019-03-28
      DOI: 10.3390/electronics8040380
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 381: Adaptive Power Allocation Scheme for
           Mobile NOMA Visible Light Communication System

    • Authors: Zanyang Dong, Tao Shang, Qian Li, Tang Tang
      First page: 381
      Abstract: Recently, due to its higher spectral efficiency and enhanced user experience, non-orthogonal multiple access (NOMA) has been widely studied in visible light communication (VLC) systems. As a main concern in NOMA-VLC systems, the power allocation scheme greatly affects the tradeoff between the total achievable data rate and user fairness. In this context, our main aim in this work was to find a more balanced power allocation scheme. To this end, an adaptive power allocation scheme based on multi-attribute decision making (MADM), which flexibly chooses between conventional power allocation or inverse power allocation (IPA) and the optimal power allocation factor, has been proposed. The concept of IPA is put forward for the first time and proves to be beneficial to achieving a higher total achievable data rate at the cost of user fairness. Moreover, considering users’ mobility along certain trajectories, we derived a fitting model of the optimal power allocation factor. The feasibility of the proposed adaptive scheme was verified through simulation and the fitting model was approximated to be the sum of three Gaussian functions.
      Citation: Electronics
      PubDate: 2019-03-29
      DOI: 10.3390/electronics8040381
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 382: Design of Cascaded CORDIC Based on Precise
           Analysis of Critical Path

    • Authors: Pramod Kumar Meher, Sang Yoon Park
      First page: 382
      Abstract: A conventional coordinate rotation digital computer (CORDIC) has a low throughput rate due to its recursive implementation of micro-rotations. On the contrary, a fully-pipelined cascaded CORDIC provides a very high throughput rate at the cost of high complexity and large area. In this paper, possible design choices of cascaded CORDIC are explored over a wide range of operating frequencies, throughput rates, latency, and area complexity. For this purpose, we present a fine-grained critical path analysis of the cascaded CORDIC in terms of bit-level delay. Based on the propagation delay estimate, we propose an algorithm for determining the required number of pipeline stages and locations of the pipeline registers in order to meet the time constraint in a particular application. A hybrid cascaded-recursive CORDIC is also proposed to increase the throughput rate, and to reduce the latency and energy per sample (EPS). From synthesis results, we show that the proposed pipelined cascaded CORDIC with only four pipeline stages requires 31.1% less area and 29.0% less EPS compared to a fully-pipelined CORDIC. An eight stage pipelined recursive cascaded CORDIC provides 18.3% less EPS and 40.4% less area-delay product than a conventional CORDIC.
      Citation: Electronics
      PubDate: 2019-03-29
      DOI: 10.3390/electronics8040382
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 383: Analysis of Memory Matrices with HfO2
           Memristors in a PSpice Environment

    • Authors: Mladenov
      First page: 383
      Abstract: The investigation of new memory circuits is very important for the development of future generations’ non-volatile and Random Access Memories (RAM) memories and modern schemes for in-memory calculations. The purpose of the present research is to propose a detailed analysis of passive and hybrid memristor-based memory crossbars with separating metal oxide semiconductor (MOS) transistors. The considered memristors are based on HfO2. The transistors are applied to eliminate the parasitic paths in the schemes. For simulations, a previously proposed strongly nonlinear modified window function by the author together with a physical nonlinear memristor model is used. The considered model is adjusted according to the experimental i–v relationship of HfO2 memristors. The i–v relationship obtained by the simulation is successfully fitted to the respective relationship derived by physical measurements. A good coincidence between these characteristics is established. Several basic window functions are also applied for comparison to the corresponding results. The proposed model is analyzed in Personal Simulation Program with Integrated Circuit Emphasis (PSpice) and it is also used for simulation of a 5 × 5 fragment of a memristor memory crossbar with isolating transistors and for the analysis of a 6 × 6 passive memory matrix. The investigated matrices are simulated for writing, reading, and erasing information. It is established that the model proposed could be used for simulations of complex memristor circuits.
      Citation: Electronics
      PubDate: 2019-03-29
      DOI: 10.3390/electronics8040383
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 384: Green Computing in Sensors-Enabled
           Internet of Things: Neuro Fuzzy Logic-Based Load Balancing

    • Authors: Kumar Kashyap, Kumar, Dohare, Kumar, Kharel
      First page: 384
      Abstract: Energy is a precious resource in the sensors-enabled Internet of Things (IoT). Unequal load on sensors deplete their energy quickly, which may interrupt the operations in the network. Further, a single artificial intelligence technique is not enough to solve the problem of load balancing and minimize energy consumption, because of the integration of ubiquitous smart-sensors-enabled IoT. In this paper, we present an adaptive neuro fuzzy clustering algorithm (ANFCA) to balance the load evenly among sensors. We synthesized fuzzy logic and a neural network to counterbalance the selection of the optimal number of cluster heads and even distribution of load among the sensors. We developed fuzzy rules, sets, and membership functions of an adaptive neuro fuzzy inference system to decide whether a sensor can play the role of a cluster head based on the parameters of residual energy, node distance to the base station, and node density. The proposed ANFCA outperformed the state-of-the-art algorithms in terms of node death rate percentage, number of remaining functioning nodes, average energy consumption, and standard deviation of residual energy.
      Citation: Electronics
      PubDate: 2019-03-29
      DOI: 10.3390/electronics8040384
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 385: Three-Stream Convolutional Neural Network
           with Squeeze-and-Excitation Block for Near-Infrared Facial Expression
           Recognition

    • Authors: Chen, Zhang, Zhong, Chen, Chen, Yu
      First page: 385
      Abstract: Near-infrared (NIR) facial expression recognition is resistant to illumination change. In this paper, we propose a three-stream three-dimensional convolution neural network with a squeeze-and-excitation (SE) block for NIR facial expression recognition. We fed each stream with different local regions, namely the eyes, nose, and mouth. By using an SE block, the network automatically allocated weights to different local features to further improve recognition accuracy. The experimental results on the Oulu-CASIA NIR facial expression database showed that the proposed method has a higher recognition rate than some state-of-the-art algorithms.
      Citation: Electronics
      PubDate: 2019-03-29
      DOI: 10.3390/electronics8040385
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 386: A Joint Strategy for Fair and Efficient
           Energy Usage in WLANs in the Presence of Capture Effect

    • Authors: Bilal Khan, Rana Asif Rehman, Byung-Seo Kim
      First page: 386
      Abstract: Capture effect has been shown as a physical layer (PHY) phenomenon of modern wireless devices that improves the performance of wireless local area networks (WLANs) in terms of throughput. In this paper, however, we explore the effect of PHY capture in the domain of energy efficiency. Analysis model that takes into account the effect of PHY capture is backed up by ns-2 simulations show that capture effect improves energy efficiency of WLAN by 20%. This improvement, however, results in unfairness, i.e, a group of nodes located far away from the Access Point (AP) is three times less energy efficient than the group of nodes located closer to the AP. To resolve the unfairness caused by the capture effect, furthermore, this paper proposes a joint strategy of adaptive transmission power control (ATXPR) and contention window adjustment (CWADJ). Namely, a node that suffers transmission failure due to another node capturing the channel steps up its transmission power according to the transmission power control algorithm and refrains from increasing its contention window according to contention window adjustment mechanism, respectively. Our proposed joint strategy is 99% fair while maintaining overall energy efficiency of the network.
      Citation: Electronics
      PubDate: 2019-03-30
      DOI: 10.3390/electronics8040386
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 387: Layer-Edge Patterns Exploration and
           Presentation in Multiplex Networks: From Detail to Overview via Selections
           and Aggregations

    • Authors: Zhang, Wu, Yu, Li
      First page: 387
      Abstract: Multiplex networks have been widely used to describe the multi-type connections of entities in the real world. However, researches for multiplex networks visualization unilaterally focus on the presentation of topological structure, lacking of specific high-level information presentation for quantitative comparison of interlayer structure. Users cannot participate in the exploration and freely choose the layers (or sub-graphs, regions, etc.) of interest for structural comparison. Contraposing the layer-edge patterns visual analysis tasks of multiplex networks, this paper puts forward a novel solution for exploration and analysis that tightly couples topological structure and high-level patterns. It mainly contains a multi-force directed model to realize the balanced layout of nodes in multi-layer topology, as well as two kinds of high-level patterns of which the visual representations are, respectively, designed by a familiar metaphor—that is, the similar pattern representation based on the area-proportional Venn diagrams and the interaction pattern representation based on the directed arrows. Furthermore, views association is implemented through underlying data sharing and multiple interactions which can be used to gain insights through the creation of selections of interest and produce high-level infographic-style overviews simultaneously. The experiments on real-world data demonstrate the support of the proposed method for layer-edge patterns analysis tasks in multiplex networks and the effectiveness for analyzing the multi-layer structure of multiplex networks.
      Citation: Electronics
      PubDate: 2019-03-30
      DOI: 10.3390/electronics8040387
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 388: A Novel Finite-Control-Set Model
           Predictive Directive Torque Control Strategy of Permanent Magnet
           Synchronous Motor with Extended Output

    • Authors: Mingxing Du, Ye Tian, Wenbai Wang, Ziwei Ouyang, Kexin Wei
      First page: 388
      Abstract: The performance of conventional direct torque control strategy from the viewpoint of flux and torque ripples has been unsatisfactory. Therefore, this study aims to propose a novel finite-control-set model predictive direct torque control strategy with extended output based on two-step prediction. An appropriate pre-selected vector, which is modulated in a specific manner, is selected through a look-up table and then used to optimise the pre-selected voltage vector based on the computing result from the model prediction and output it. The proposed strategy extends the range of the vectors that can be used to enhance the flux and torque control performance and reduce ripples and computational complexity in comparison with the conventional finite-control-set model predictive direct torque control. The feasibility of the proposed method is verified by conducting a verification test using dSPACE and Tyhpoon HIL 402 experimental platform.
      Citation: Electronics
      PubDate: 2019-03-31
      DOI: 10.3390/electronics8040388
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 389: An Analysis of the Impact of LED Tilt on
           Visible Light Positioning Accuracy

    • Authors: David Plets, Sander Bastiaens, Luc Martens, Wout Joseph
      First page: 389
      Abstract: Whereas the impact of photodiode noise and reflections is heavily studied in Visible Light Positioning (VLP), an often underestimated deterioration of VLP accuracy is caused by tilt of the Light Emitting Diodes (LEDs). Small LED tilts may be hard to avoid and can have a significant impact on the claimed centimeter-accuracy of VLP systems. This paper presents a Monte-Carlo-based simulation study of the impact of LED tilt on the accuracy of Received Signal Strength (RSS)-based VLP for different localization approaches. Results show that trilateration performs worse than (normalized) Least Squares algorithms, but mainly outside the LED square. Moreover, depending on inter-LED distance and LED height, median tilt-induced errors are in the range between 1 and 6 cm for small LED tilts, with errors scaling linearly with the LED tilt severity. Two methods are proposed to estimate and correct for LED tilts and their performance is compared.
      Citation: Electronics
      PubDate: 2019-04-01
      DOI: 10.3390/electronics8040389
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 390: Protecting Private Communications in
           Cyber-Physical Systems through Physical Unclonable Functions

    • Authors: Marina Pérez-Jiménez, Borja Bordel Sánchez, Andrea Migliorini, Ramón Alcarria
      First page: 390
      Abstract: Cyber-physical systems (CPS) are envisioned to change the whole of society. New engineered systems joining physical and digital solutions are being employed in industry, education, etc. These new systems are networked by default, and private information is shared among the different components related to users, critical infrastructures, or business operations. In this context, it is essential to encrypt those communication links to protect such information. However, even most complicated schemes based on hybrid (asymmetric and symmetric) solutions, finally require physical devices to store a secret key. This approach is cryptographically weak, as any person with physical access to the device could obtain that key. Therefore, in this paper we propose the use of physical unclonable functions (PUF) to generate secret keys for lightweight encryption schemes. Using PUFs, any attempt to capture the key is changing the original secret stream, and even manufacturers are not able to build two identical PUFs. The proposed key generator is based on magnetic materials and lightweight pseudorandom number generators to meet the low-cost and small size requirements of CPS. In particular, materials with an activated exchange-bias effect are employed, together with simple copper coils. The encryption process can be based on a simple XOR gate because of the robustness of the proposed key generator. In order to evaluate the performance of the proposed technology, an experimental validation based on simulation scenarios is also provided.
      Citation: Electronics
      PubDate: 2019-04-01
      DOI: 10.3390/electronics8040390
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 391: Writer Identification Using Handwritten
           Cursive Texts and Single Character Words

    • Authors: Tobias Kutzner, Carlos F. Pazmiño-Zapatier, Matthias Gebhard, Ingrid Bönninger, Wolf-Dietrich Plath, Carlos M. Travieso
      First page: 391
      Abstract: One of the biometric methods in authentication systems is the writer verification/identification using password handwriting. The main objective of this paper is to present a robust writer verification system by using cursive texts as well as block letter words. To evaluate the system, two datasets have been used. One of them is called Secure Password DB 150, which is composed of 150 users with 18 samples of single character words per user. Another dataset is public and called IAM online handwriting database, and it is composed of 220 users of cursive text samples. Each sample has been defined by a set of features, composed of 67 geometrical, statistical, and temporal features. In order to get more discriminative information, two feature reduction methods have been applied, Fisher Score and Info Gain Attribute Evaluation. Finally, the classification system has been implemented by hold-out cross validation and k-folds cross validation strategies for three different classifiers, K-NN, Naïve Bayes and Bayes Net classifiers. Besides, it has been applied for verification and identification approaches. The best results of 95.38% correct classification are achieved by using the k-nearest neighbor classifier for single character DB. A feature reduction by Info Gain Attribute Evaluation improves the results for Naïve Bayes Classifier to 98.34% for IAM online handwriting DB. It is concluded that the set of features and its reduction are a strong selection for the based-password handwritten writer identification in comparison with the state-of-the-art.
      Citation: Electronics
      PubDate: 2019-04-01
      DOI: 10.3390/electronics8040391
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 392: Impact of Co-Channel Interference on
           Two-Way Relaying Networks with Maximal Ratio Transmission

    • Authors: Awfa Aladwani, Eylem Erdogan, Tansal Gucluoglu
      First page: 392
      Abstract: Amplify-and-forward (AF) two-way relay networks (TWRNs) have become popular to provide spectrally efficient communication when range extension or energy efficiency is needed by utilizing a simple relay. However, their performance can be significantly degraded in practice due to co-channel interference (CCI) which is increasing due to growing number of wireless devices and recent cognitive and non-orthogonal multiple access techniques. With the motivation of improving the performance of AF-TWRNs, the use of maximal ratio transmission (MRT) is investigated to achieve high reliability while requiring low receiver complexity for the relay. First, the signal-to-interference-plus-noise ratio (SINR) expression is formulated and upper bounded. Then, tight lower bound expressions of outage probability (OP), sum symbol error rate (SSER), and upper bound ergodic sum rate (ESR) for each source and for the overall system are obtained. Besides, array and diversity gains are provided after deriving the asymptotic expressions of OP and SSER at high signal-to-noise ratio (SNR). Furthermore, the impact of channel estimation errors on the performance is also included. Finally, Monte Carlo simulation results which corroborate our theoretical findings are illustrated.
      Citation: Electronics
      PubDate: 2019-04-01
      DOI: 10.3390/electronics8040392
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 393: A Method for the Analysis of Interference
           from DME to ATCRBS in the Time Domain

    • Authors: Guofeng Jiang, Yangyu Fan, Hongbo Yuan, Pengliang Yuan
      First page: 393
      Abstract: Analysis of the coexistence of two or more types of equipment is increasingly important. However, at present studies on the analysis method in the time domain are scant. Therefore, the aim of this paper is to explore the characteristics of signals and relations between interfering and desired signals in the time domain. Based on the periodicity of a signal, this paper presents a Periodic Pulse Overlap Method (PPOM). Using PPOM to analyze the interference from Distance Measuring Equipment (DME) to Air Traffic Control Radar Beacon System (ATCRBS) in the time domain, we obtain almost the same result as that based on the Monte Carlo Method (MCM). Furthermore, we discover the measures to reduce or even avoid interference, such as changing the Pulse Recurrence Frequency (PRF), adjusting the difference of initial time, and switching the operating modes of the equipment.
      Citation: Electronics
      PubDate: 2019-04-01
      DOI: 10.3390/electronics8040393
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 394: A Fractional-Order Kinetic Battery Model
           of Lithium-Ion Batteries Considering a Nonlinear Capacity

    • Authors: Qi Zhang, Yan Li, Yunlong Shang, Bin Duan, Naxin Cui, Chenghui Zhang
      First page: 394
      Abstract: Accurate battery models are integral to the battery management system and safe operation of electric vehicles. Few investigations have been conducted on the influence of current rate (C-rate) on the available capacity of the battery, for example, the kinetic battery model (KiBaM). However, the nonlinear characteristics of lithium-ion batteries (LIBs) are closer to a fractional-order dynamic system because of their electrochemical materials and properties. The application of fractional-order models to represent physical systems is timely and interesting. In this paper, a novel fractional-order KiBaM (FO-KiBaM) is proposed. The available capacity of a ternary LIB module is tested at different C-rates, and its parameter identifications are achieved by the experimental data. The results showed that the estimated errors of available capacity in the proposed FO-KiBaM were low over a wide applied current range, specifically, the mean absolute error was only 1.91%.
      Citation: Electronics
      PubDate: 2019-04-02
      DOI: 10.3390/electronics8040394
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 395: A 7.5–9 GHz GaAs Two-Channel
           Multi-Function Chip

    • Authors: Shancheng Zhou, Shouli Zhou, Jingle Zhang, Jianmin Wu, Haiqing Yang, Zhiyu Wang
      First page: 395
      Abstract: Based on the 0.5 μm GaAs enhancement/depletion (E/D) Pseudomorphic High Electron Mobility Transistor (pHEMT) process, a 7.5–9 GHz two-channel amplitude phase control multi-function chip (MFC) was developed successfully. The chip was integrated with a 6-bit digital phase shifter, a 6-bit digital attenuator, and a single pole single throw (SPST) switch in each channel. A design for the absorptive SPST switch is deployed to optimize the return loss and control channel array calibration. In the 8 dB and 16 dB attenuation bit, a switched-path-type topology is employed in order to obtain a good flatness of attenuation characteristic and achieve low additive phase shift. A 27-bit serial-to-parallel converter (SPC) was introduced to decrease the control lines and pads of the chip, and the power consumption was less than 70 mW. The measurement result shows that the insertion loss is less than −13 dB and the return loss is better than −19 dB. In both channels, the 64-state root mean square (RMS) errors of the phase shifter is less than 2° and the RMS parasitic amplitude error is less than 0.2 dB. The RMS attenuation error is less than 0.45 dB and the RMS parasitic phase error is less than 2.4°. The size of the chip is 3.5 mm × 4.5 mm.
      Citation: Electronics
      PubDate: 2019-04-02
      DOI: 10.3390/electronics8040395
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 396: A Novel Arc Fault Detection Method
           Integrated Random Forest, Improved Multi-scale Permutation Entropy and
           Wavelet Packet Transform

    • Authors: Yin, Wang, Zhang, Gao
      First page: 396
      Abstract: Arc faults are one of the important causes of electric fires. In order to solve the problem of randomness, diversity, the concealment of series arc faults and to improve the detection accuracy, a novel arc fault detection method integrated random forest (RF), improved multi-scale permutation entropy (IMPE) and wavelet packet transform (WPT) are designed. Firstly, singular value decomposition (SVD) was applied to filter the current signal and then the high-dimensional fault features were constructed by extracting IMPE, the wavelet packet energy and the wavelet packet energy-entropy. Afterward, the high-dimensional fault features were employed to train the RF to realize the arc fault detection of different load types and the experimental results verify the effectiveness of the arc fault detection method designed in this paper. Finally, the comparative experiments demonstrates that the RF shows better performance in arc fault detection compared to the back-propagation neural network (BPNN) and least squares support vector machines (LSSVM), and that the experiments of transient events indicate that RF is able to effectively avoid incorrectly detecting different load types during the start operations and stop operations.
      Citation: Electronics
      PubDate: 2019-04-02
      DOI: 10.3390/electronics8040396
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 397: Stackelberg Game-Theoretic Low Probability
           of Intercept Performance Optimization for Multistatic Radar System

    • Authors: Chenguang Shi, Wei Qiu, Fei Wang, Sana Salous, Jianjiang Zhou
      First page: 397
      Abstract: In this paper, the problem of Stackelberg game-theoretic low probability of intercept (LPI) performance optimization in multistatic radar system is investigated. The goal of the proposed LPI optimization strategy is to minimize the transmitted power of each radar while satisfying a predetermined signal-to-interference-plus-noise ratio (SINR) requirement for target detection. Firstly, a single-leader multi-follower Stackelberg game is adopted to formulate the LPI optimization problem of multistatic radar system. In the considered game model, the hostile intercept receiver plays a role of leader, who decides the prices of power resource first through the maximization of its own utility function. The multiple radars are followers to compete with each other in a non-cooperative game according to the imposed prices from the intercept receiver subsequently. Then, the Nash equilibrium (NE) for the considered game model is derived, and the existence and uniqueness of the NE are analytically proved. Furthermore, a pricing-based distributed iterative power control algorithm is proposed. Finally, some simulation examples are provided to demonstrate that the proposed scheme has remarkable potential to enhance the LPI performance of the multistatic radar system.
      Citation: Electronics
      PubDate: 2019-04-02
      DOI: 10.3390/electronics8040397
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 398: Predictor-Based Motion Tracking Control
           for Cloud Robotic Systems with Delayed Measurements

    • Authors: Shaobo Shen, Aiguo Song, Tao Li
      First page: 398
      Abstract: This paper addresses the problem of motion prediction and tracking control for cloud robotic systems with time-varying delays in measurements. A novel method using an observer-based structure for position and velocity prediction is developed to estimate the real-time information of robot manipulator. The prediction error can converge to zero even if model uncertainties exist in the robot manipulator. Based on the predicted positions and velocities, some sufficient conditions are derived to design suitable tracking controllers such that semi-globally uniformly ultimately bounded tracking performance of the predictor–controller couple can be guaranteed. Finally, the effectiveness and robustness to model uncertainties of the proposed method are verified by a two degree-of-freedom (DOF) robot system.
      Citation: Electronics
      PubDate: 2019-04-03
      DOI: 10.3390/electronics8040398
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 399: Enhancement of System Stability Based on
           PWFM

    • Authors: Hwu, Wang, Yau
      First page: 399
      Abstract: In this paper, a pulse width and frequency modulation (PWFM) control strategy is presented, which combines the one-comparator counter-based pulse width modulation (PWM) control with pulse frequency modulation (PFM) control to increase pseudo-1-bit resolution under constant-frequency operation. Accordingly, system stability will be enhanced significantly. As compared with the traditional counter-based PWM control, there is no difference in off-chip circuit complexity except a slight change in on-chip hardware. Finally, a prototype circuit is used to verify the proposed control concept by some experimental results with no limit cycle oscillation.
      Citation: Electronics
      PubDate: 2019-04-03
      DOI: 10.3390/electronics8040399
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 400: A Circularly Polarized Antenna Array with
           Gain Enhancement for Long-Range UHF RFID Systems

    • Authors: Hu, Wen, Inserra, Huang, Li, Chen
      First page: 400
      Abstract: A 2 × 2 circularly polarized (CP) sequential rotation microstrip patch antenna array with high gain for long-range ultra-high frequency (UHF) radio frequency identification (RFID) communication is proposed in this paper. In order to meet the operational frequency band requirement of 840–960 MHz and, at the same time, achieve enhanced broadside gain, a two-level sequential rotation structure is developed. Series power divider is used as the basic element of the feed network that is implemented with the substrate-integrated coaxial line technology for minimizing radiation losses. The manufactured prototype exhibits a peak gain of 12.5 dBic at 900 MHz and an axial ratio (AR) bandwidth (AR ≤ 3 dB) of 18.2% from 828 to 994 MHz. In comparison with the state-of-the-art, the proposed antenna shows an excellent gain/size trade-off.
      Citation: Electronics
      PubDate: 2019-04-03
      DOI: 10.3390/electronics8040400
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 401: Advanced Backstepping Trajectory Control
           for Skid-Steered Duct-Cleaning Mobile Platforms

    • Authors: Wootae Jeong, Seungwoo Jeon, Dahae Jeong
      First page: 401
      Abstract: In recent years, a novel skid-steered duct-cleaning mobile platform was developed to remove dust accumulated on the inner surface of an air-ventilation duct with its rolling brushes. During the cleaning process, the irregular brushing pressure acting on the upper arm makes it difficult to control the platform through the duct path. In fact, the repulsive external force due to the brushing pressure is not directly measurable or computable because of the nonlinear deformation of the brush. In addition, dynamic uncertainties in platform motion can occur during reciprocating motion of the upper arm. Therefore, a model-based trajectory-tracking controller is required to control the mobile cleaning platform by considering irregular external forces. The robustness of the developed controller based on the adaptable PD(Proportional-Derivative)-backstepping method has been proposed and evaluated through numerical analysis and experiments. For the turning motion in a narrow space, a skid-steered platform model considering wheel slippage has been also implemented. The result shows that tracking control can be successfully achieved under various conditions of frequencies in brushing-arm motion and torque limitation of the traction motors.
      Citation: Electronics
      PubDate: 2019-04-04
      DOI: 10.3390/electronics8040401
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 402: Nonlinear Effects of Three-Level
           Neutral-Point Clamped Inverter on Speed Sensorless Control of Induction
           Motor

    • Authors: Peifei Li, Lei Zhang, Bin Ouyang, Yong Liu
      First page: 402
      Abstract: In the model reference adaptive speed observer, the induction motor supply voltage is used as the input of the reference model. However, measuring the supply voltage complicates the system and increases the cost, so the command voltage calculated by the controller is generally used instead of the actual supply voltage in the drive system. However, due to the nonlinear effects of the inverter, the voltage calculated by the controller is different from the actual supply voltage, resulting in a speed observation deviation. This paper analyzes the multiple effects that cause the three-level neutral-point clamped (TL-NPC) inverter output voltage and command voltage deviation. A voltage deviation compensation measure based on the volt-second balance principle is proposed. In this context, the expression of the rotational speed deviation caused by the voltage deviation is derived rigorously and in detail. Finally, the effectiveness of the voltage compensation measure is verified by experiments. The experimental results are basically consistent with the theoretical derivation expressions. The method and analysis in this paper is applicable to induction motor speed sensorless control systems driven by two-level and other multilevel inverters.
      Citation: Electronics
      PubDate: 2019-04-04
      DOI: 10.3390/electronics8040402
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 403: High-Performance Low-Pass Filter Using
           Stepped Impedance Resonator and Defected Ground Structure

    • Authors: Jin Zhang, Ruosong Yang, Chen Zhang
      First page: 403
      Abstract: A microstrip low-pass filter (LPF) using reformative stepped impedance resonator (SIR) and defected ground structure (DGS) is proposed in this paper. The proposed filter not only possesses the advantage of high frequency selectivity of SIR hairpin LPF with internal coupling, but also possesses the large stop-band (SB) bandwidth by adjusting the number and area of DGS units. The LPF proposed in this paper possesses the properties of miniaturization, wide SB, high selectivity, and low pass-band ripple (PBR) simultaneously. The characteristic parameters of the proposed LPF is that: the pass-band (PB) is 0~2 GHz, the PBR is 0.5 dB, the SB range is from 2.4 GHz to 9 GHz when the attenuation is under 20 dB, and the maximal attenuation could reach 45 dB in the SB. The size of this proposed LPF is 0.13 λ × 0.09 λ ; λ is the corresponding wavelength of the upper PB edge frequency of 2 GHz.
      Citation: Electronics
      PubDate: 2019-04-04
      DOI: 10.3390/electronics8040403
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 404: An Analytical Cost-Optimal Cloudlet
           Placement Framework over Fiber-Wireless Networks with Quasi-Convex Latency
           Constraint

    • Authors: Sourav Mondal, Goutam Das, Elaine Wong
      First page: 404
      Abstract: To meet the low-latency constraints arising from future smart mobile devices, Internet-of-Things, and 5G applications, major interest is currently given to the integration of centralized cloud computing and distributed edge computing infrastructures to deliver higher performance and reliability to edge devices in accessing mobile cloud services. The three-tier network architecture arising from cloud, cloudlet, and edge-devices can handle miscellaneous latency requirements for both latency-sensitive and latency-tolerant applications more efficiently than conventional two-tier networks. In this paper, we primarily focus on the static cloudlet network planning problem and propose an analytical hybrid cost-optimization framework for optimal cloudlet placement. We formulate this problem as a convex optimization problem and solve by using Karush-Kuhn-Tucker (KKT) conditions, and show that this framework can be evaluated without any scalability issues observed with integer programming based frameworks for large datasets. Moreover, we derive user-friendly closed form expressions that provide a first-hand estimation of cloudlet deployment cost depending on a few important network parameters like split-ratio, population density, and network bandwidth. Finally, we also show that the optimal solution of this analytical framework can be considered as a tight lower bound of the optimal solutions of integer programming based frameworks and makes a better cloudlet installation cost estimation compared to other existing frameworks.
      Citation: Electronics
      PubDate: 2019-04-05
      DOI: 10.3390/electronics8040404
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 405: Comprehensive Comparative Analysis of
           Impedance-Source Networks for DC and AC Application

    • Authors: Husev, Shults, Vinnikov, Roncero-Clemente, Romero-Cadaval, Chub
      First page: 405
      Abstract: This paper presents a comprehensive analytical comparison of the impedance-source-based dc-dc and dc-ac converters in terms of the passive component count and size, semiconductor stress, and range of input voltage variation. The conventional solution with a boost converter was considered as a reference value. The main criterion of the comprehensive comparison was the energy stored in the passive elements, which was considered both under a constant and predefined high frequency current ripple in the inductors and the voltage ripple across the capacitors. Main impedance-source converters with or without a transformer and with or without inductor coupling were analyzed. Dc-dc and dc-ac applications were considered. Selective simulation results along with experimental verification are shown. The conclusions provide a selection guide of impedance-source networks for different applications taking into account its advantages and disadvantages.
      Citation: Electronics
      PubDate: 2019-04-05
      DOI: 10.3390/electronics8040405
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 406: Simulation of AlGaN/GaN HEMTs’ Breakdown
           Voltage Enhancement Using Gate Field-Plate, Source Field-Plate and Drain
           Field Plate

    • Authors: Biyan Liao, Quanbin Zhou, Jian Qin, Hong Wang
      First page: 406
      Abstract: A 2-D simulation of off-state breakdown voltage (VBD) for AlGaN/GaN high electron mobility transistors (HEMTs) with multi field-plates (FPs) is presented in this paper. The effect of geometrical variables of FP and insulator layer on electric field distribution and VBD are investigated systematically. The FPs can modulate the potential lines and distribution of an electric field, and the insulator layer would influence the modulation effect of FPs. In addition, we designed a structure of HEMT which simultaneously contains gate FP, source FP and drain FP. It is found that the VBD of AlGaN/GaN HEMTs can be improved greatly with the corporation of gate FP, source FP and drain FP. We achieved the highest VBD in the HEMT contained with three FPs by optimizing the structural parameters including length of FPs, thickness of FPs, and insulator layer. For HEMT with three FPs, FP-S alleviates the concentration of the electric field more effectively. When the length of the source FP is 24 μm and the insulator thickness between the FP-S and the AlGaN surface is 1950 nm, corresponding to the average electric field of about 3 MV/cm at the channel, VBD reaches 2200 V. More importantly, the 2D simulation model is based on a real HMET device and will provide guidance for the design of a practical device.
      Citation: Electronics
      PubDate: 2019-04-07
      DOI: 10.3390/electronics8040406
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 407: Frequency and Pattern Reconfigurable
           Antenna for Emerging Wireless Communication Systems

    • Authors: Amjad Iqbal, Amor Smida, Nazih Khaddaj Mallat, Ridha Ghayoula, Issa Elfergani, Jonathan Rodriguez, Sunghwan Kim
      First page: 407
      Abstract: A printed and minimal size antenna having the functionality of frequency shifting as well as pattern reconfigurability is presented in this work. The antenna proposed in this work consists of three switches. Switch 1 is a lumped switch that controls the operating bands of the antenna. Switch 2 and Switch 3 controls the beam switching of the antenna. When the Switch 1 is ON, the proposed antenna operates at 3.1 GHz and 6.8 GHz, covering the 2.5–4.2 GHz and 6.2–7.4 GHz bands, respectively. When Switch 1 is OFF, the antenna operates only at 3.1 GHz covering the 2.5–4.2 GHz band. The desired beam from the antenna can be obtained by adjusting the ON and OFF states of Switches 2 and 3. Unique beams can be obtained by different combination of ON and OFF states of the Switches 2 and 3. A gain greater than 3.7 dBi is obtained for all four cases.
      Citation: Electronics
      PubDate: 2019-04-07
      DOI: 10.3390/electronics8040407
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 408: Forward Converter Current Fed Equalizer
           for Lithium Based Batteries in Ultralight Electrical Vehicles

    • Authors: Ali Farzan Moghaddam, Alex Van den Bossche
      First page: 408
      Abstract: In this paper, the concept of a forward balancing technique fed by a buck converter for lithium-based batteries in Electrical Vehicle (EV) applications is investigated. The proposed active topology equalizes eight cells in a series in a battery pack, by using a forward converter for each battery pack and the whole battery packs, using a buck converter. The battery bank consists of four battery packs, which are in series. Therefore, the proposed system will equalize 32 cells in series. In this paper, the proposed circuit employs a single transistor used in a Zero Voltage Switch (ZVS) for the forward converter. In practice, this means a capacitor in parallel with the switch at the same time a demagnetizing of the transformer is obtained. The circuit realizes a low Electromagnetic Interference (EMI) and reduces ringing. To overcome the problem of many pins on a coil former, the transformer secondary windings are made by using hairpin winding, on a ring core. It permits, e.g., having eight secondaries and uniform output voltages. Each secondary winding is made by two hairpin turns using two zero-Ohm resistors in series. The proposed topology has less components and circuitry, and it can equalize multiple battery packs by using a single buck converter and several forward converters for each battery pack. Experimental and simulation results are performed to verify the viability of the proposed topology.
      Citation: Electronics
      PubDate: 2019-04-08
      DOI: 10.3390/electronics8040408
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 409: Electronic Circuit with Controllable
           Negative Differential Resistance and its Applications

    • Authors: Vladimir Ulansky, Ahmed Raza, Hamza Oun
      First page: 409
      Abstract: Electronic devices and circuits with negative differential resistance (NDR) are widely used in oscillators, memory devices, frequency multipliers, mixers, etc. Such devices and circuits usually have an N-, S-, or Λ-type current-voltage characteristics. In the known NDR devices and circuits, it is practically impossible to increase the negative resistance without changing the type or the dimensions of transistors. Moreover, some of them have three terminals assuming two power supplies. In this paper, a new NDR circuit that comprises a combination of a field effect transistor (FET) and a simple bipolar junction transistor (BJT) current mirror (CM) with multiple outputs is proposed. A distinctive feature of the proposed circuit is the ability to change the magnitude of the NDR by increasing the number of outputs in the CM. Mathematical expressions are derived to calculate the threshold currents and voltages of the N-type current-voltage characteristics for various types of FET. The calculated current and voltage thresholds are compared with the simulation results. The possible applications of the proposed NDR circuit for designing single-frequency oscillators and voltage-controlled oscillators (VCO) are considered. The designed NDR VCO has a very low level of phase noise and has one of the best values of a standard figure of merit (FOM) among recently published VCOs. The effectiveness of the proposed oscillators is confirmed by the simulation results and the implemented prototype.
      Citation: Electronics
      PubDate: 2019-04-08
      DOI: 10.3390/electronics8040409
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 410: Stereo Matching in
           Address-Event-Representation (AER) Bio-Inspired Binocular Systems in a
           Field-Programmable Gate Array (FPGA)

    • Authors: Dominguez-Morales, Domínguez-Morales, Jiménez-Fernández, Linares-Barranco, Jiménez-Moreno
      First page: 410
      Abstract: In stereo-vision processing, the image-matching step is essential for results, although it involves a very high computational cost. Moreover, the more information is processed, the more time is spent by the matching algorithm, and the more inefficient it is. Spike-based processing is a relatively new approach that implements processing methods by manipulating spikes one by one at the time they are transmitted, like a human brain. The mammal nervous system can solve much more complex problems, such as visual recognition by manipulating neuron spikes. The spike-based philosophy for visual information processing based on the neuro-inspired address-event-representation (AER) is currently achieving very high performance. The aim of this work was to study the viability of a matching mechanism in stereo-vision systems, using AER codification and its implementation in a field-programmable gate array (FPGA). Some studies have been done before in an AER system with monitored data using a computer; however, this kind of mechanism has not been implemented directly on hardware. To this end, an epipolar geometry basis applied to AER systems was studied and implemented, with other restrictions, in order to achieve good results in a real-time scenario. The results and conclusions are shown, and the viability of its implementation is proven.
      Citation: Electronics
      PubDate: 2019-04-08
      DOI: 10.3390/electronics8040410
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 411: Privacy-Preserving Distributed Deep
           Learning via Homomorphic Re-Encryption

    • Authors: Fengyi Tang, Wei Wu, Jian Liu, Huimei Wang, Ming Xian
      First page: 411
      Abstract: The flourishing deep learning on distributed training datasets arouses worry about data privacy. The recent work related to privacy-preserving distributed deep learning is based on the assumption that the server and any learning participant do not collude. Once they collude, the server could decrypt and get data of all learning participants. Moreover, since the private keys of all learning participants are the same, a learning participant must connect to the server via a distinct TLS/SSL secure channel to avoid leaking data to other learning participants. To fix these problems, we propose a privacy-preserving distributed deep learning scheme with the following improvements: (1) no information is leaked to the server even if any learning participant colludes with the server; (2) learning participants do not need different secure channels to communicate with the server; and (3) the deep learning model accuracy is higher. We achieve them by introducing a key transform server and using homomorphic re-encryption in asynchronous stochastic gradient descent applied to deep learning. We show that our scheme adds tolerable communication cost to the deep learning system, but achieves more security properties. The computational cost of learning participants is similar. Overall, our scheme is a more secure and more accurate deep learning scheme for distributed learning participants.
      Citation: Electronics
      PubDate: 2019-04-09
      DOI: 10.3390/electronics8040411
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 412: CCTV Video Processing Metadata Security
           Scheme Using Character Order Preserving-Transformation in the Emerging
           Multimedia

    • Authors: Jinsu Kim, Namje Park, Geonwoo Kim, Seunghun Jin
      First page: 412
      Abstract: Intelligent video surveillance environments enable the gathering of various types of information about the object being recorded, through the analysis of real-time video data collected from CCTV systems and the automated processing that utilize the information. However, the surveillance environments face the risks of privacy exposure, which necessitates secure countermeasures. Video meta-data, in particular, contain various types of personal information that is analyzed based on big data and are thus fraught with high levels of confidentiality breaches. Despite such risks, it is not appropriate to implement encryption for video meta-data considering the efficiency issue. This paper proposes a character order preserving (COP)-transformation technique that allows the secure protection of video meta-data. The proposed technique has the merits of preventing the recovery of original meta information through meta transformation and allowing direct queries on the data transformed, increasing significantly both security and efficiency in the video meta-data processing.
      Citation: Electronics
      PubDate: 2019-04-09
      DOI: 10.3390/electronics8040412
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 413: Efficient-Scheduling Parallel
           Multiplier-Based Ring-LWE Cryptoprocessors

    • Authors: Tuy Nguyen Tan, Hanho Lee
      First page: 413
      Abstract: This paper presents a novel architecture for ring learning with errors (LWE) cryptoprocessors using an efficient approach in encryption and decryption operations. By scheduling multipliers to work in parallel, the encryption and decryption time are significantly reduced. In addition, polynomial multiplications are conducted using radix-2 and radix-8 multiple delay feedback (MDF) architecture-based number theoretic transform (NTT) multipliers to speed up the multiplication operation. To reduce the hardware complexity of an NTT multiplier, three bit-reverse operations during the NTT and inverse NTT (INTT) processes are removed. Polynomial additions in the ring-LWE encryption phase are also arranged to work simultaneously to reduce the latency. As a result, the proposed efficient-scheduling parallel multiplier-based ring-LWE cryptoprocessors can achieve higher throughput and efficiency compared with existing architectures. The proposed ring-LWE cryptoprocessors are synthesized and verified using Xilinx VIVADO on a Virtex-7 field programmable gate array (FPGA) board. With security parameters n = 512 and q = 12,289, the proposed cryptoprocessors using radix-2 single-path delay feedback (SDF), radix-2 MDF, and radix-8 MDF multipliers perform encryption in 4.58 μ s, 1.97 μ s, and 0.89 μ s, and decryption in 4.35 μ s, 1.82 μ s, and 0.71 μ s, respectively. A comparison of the obtained throughput and efficiency with those of previous studies proves that the proposed cryptoprocessors achieve a better performance.
      Citation: Electronics
      PubDate: 2019-04-09
      DOI: 10.3390/electronics8040413
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 414: A Semi-Floating Gate Memory with Tensile
           Stress for Enhanced Performance

    • Authors: Yuan, Jiang, Sun, Chen, Zhu, Sun, Zhang
      First page: 414
      Abstract: With the continuous scaling down of devices, traditional one-transistor one-capacitor dynamic random access memory (1T-1C DRAM) has encountered great challenges originated from the large-volume capacitor and high leakage current. A semi-floating gate transistor has been proposed as a capacitor-less memory with ultrafast speed and silicon-compatible technology. In this work, a U-shaped semi-floating gate memory with strain technology has been demonstrated through TCAD simulation. Ultra-high operation speed on a timescale of 5 ns at low operation voltages (≤ 2.0 V) has been obtained. And the tensile stress induced in its channel region by using contact etch stop layer (Si3N4 capper layer) was found to significantly improve the drain current by 12.07%. Furthermore, this device demonstrated a favorable retention performance with a retention time over 1 s, and its immunity to disturbance from bit-line has also been investigated that could maintain data under the continuous worst writing disturbance operation over 10 ms.
      Citation: Electronics
      PubDate: 2019-04-09
      DOI: 10.3390/electronics8040414
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 415: Correction: Salarkaleji, M. Frequency and
           Polarization-Diversified Linear Sampling Methods for Microwave Tomography
           and Remote Sensing Using Electromagnetic Metamaterials. Electronics 2017,
           6, 85

    • Authors: Mehdi Salarkaleji, Mohammadreza Eskandari, Jimmy Ching-Ming Chen, Chung-Tse Michael Wu
      First page: 415
      Abstract: The authors would like to change the affiliation for second author, Mohammadreza Eskandari, as listed in the original version of the article [...]
      Citation: Electronics
      PubDate: 2019-04-09
      DOI: 10.3390/electronics8040415
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 416: Transversely Compact Single-Ended and
           Balanced Bandpass Filters with Source–Load-Coupled Spurlines

    • Authors: Fang Yan, Yong Mao Huang, Tao Huang, Shuai Ding, Kenian Wang, Maurizio Bozzi
      First page: 416
      Abstract: Multi-function wireless systems demand multi-channel transmit/receive (TR) modules, particularly as multiple functions are required to operate simultaneously. In each channel, passive components, including bandpass filters, must be compact, or at least transversely compact; thus, the entire circuitry of the channel will be slender, and consequently multiple channels can be parallel-arranged conveniently. In this work, single-ended and balanced bandpass filters for multi-channel applications are presented. As a unique resonator, the U-shaped stepped impedance resonator (USIR) can achieve size miniaturization compared with its corresponding uniform impedance resonator (UIR) counterpart. Hence, with the utilization of USIRs, the proposed bandpass filters are able to acquire compact transverse sizes. Moreover, by using the source–load coupling scheme, two transmission zeros (TZs) are respectively generated at the lower and upper sides of the passbands, which is useful for improvement of the selectivity performance. In addition, spurlines are introduced at the input and output ports to produce another TZ to further enhance the stopband performance, which cannot be acquired by the UIR or stepped impedance resonator (SIR). To verify the aforementioned idea, one single-ended and one balanced bandpass filter are implemented, with experimental results in good agreement with the corresponding simulations. Meanwhile, as compared with some similar works, the proposed balanced filter achieves compact transverse size, sharp selectivity skirt, and wide stopbands up to the fourth-order harmonic with suppression over 20 dB, which illustrates its suitability for differential signal transmission application in microwave circuits and systems.
      Citation: Electronics
      PubDate: 2019-04-10
      DOI: 10.3390/electronics8040416
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 417: Inverse Scattering Analysis from
           Measurement Data of Total Electric and Magnetic Fields by Means of
           Cylindrical-Wave Expansion

    • Authors: Tomonori Tsuburaya, Zhiqi Meng, Takashi Takenaka
      First page: 417
      Abstract: Microwave tomography is an effective technique to estimate material distribution, where inverse scattering analysis is performed on the assumption that accurate information on the incident field is known for a measurement curve as well as in the target region. In reality, however, the information may often be unobtainable due to multiple scattering between the transmitting antenna and the target object, or existence of unwanted waves and obstacles. In this paper, a method to extract information on incident fields from measured total field data is proposed. The validity of the proposed method is verified on 2D TMz problems, where a cylindrical, a square, and an L-shape homogeneous object are employed as a target object. Furthermore, it is shown that the method is available even when there are unwanted obstacles outside the measurement curve.
      Citation: Electronics
      PubDate: 2019-04-10
      DOI: 10.3390/electronics8040417
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 418: Implementation of Pattern Recognition
           Algorithms in Processing Incomplete Wind Speed Data for Energy Assessment
           of Offshore Wind Turbines

    • Authors: Ioannis P. Panapakidis, Constantine Michailides, Demos C. Angelides
      First page: 418
      Abstract: Offshore wind turbine (OWT) installations are continually expanding as they are considered an efficient mechanism for covering a part of the energy consumption requirements. The assessment of the energy potential of OWTs for specific offshore sites is the key factor that defines their successful implementation, commercialization and sustainability. The data used for this assessment mainly refer to wind speed measurements. However, the data may not present homogeneity due to incomplete or missing entries; this in turn, is attributed to failures of the measuring devices or other factors. This fact may lead to considerable limitations in the OWTs energy potential assessment. This paper presents two novel methodologies to handle the problem of incomplete and missing data. Computational intelligence algorithms are utilized for the filling of the incomplete and missing data in order to build complete wind speed series. Finally, the complete wind speed series are used for assessing the energy potential of an OWT in a specific offshore site. In many real-world metering systems, due to meter failures, incomplete and missing data are frequently observed, leading to the need for robust data handling. The novelty of the paper can be summarized in the following points: (i) a comparison of clustering algorithms for extracting typical wind speed curves is presented for the OWT related literature and (ii) two efficient novel methods for missing and incomplete data are proposed.
      Citation: Electronics
      PubDate: 2019-04-10
      DOI: 10.3390/electronics8040418
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 419: Robust Stable Control Design for AC Power
           Supply Applications

    • Authors: En-Chih Chang, Sung-Chi Yang, Rong-Ching Wu
      First page: 419
      Abstract: This paper applies modified feedback technology to carry out the exact steady-state and fast transient in a high-performance alternating current (AC) power supply. The presented scheme displays the virtues of a finite-time convergence control (FTCC) and a discrete grey prediction model (DGPM). The FTCC, derived from a terminal sliding-mode (TSM) design principle, can produce the finite system-state convergence time and evade the singularity. It is noteworthy that the chattering/steady-state error around the FTCC may occur because of the overestimated or underestimated uncertainty bound. The DGPM with the bound estimate ability is integrated into the FTCC to cope with internal parameter variations and external load disturbances. The less chattering and steady-state error can be obtained, providing more robust performance in the AC power supply. The combination of the FTCC and the DGPM extends the standard TSM design for the purpose of faster singularity-free convergence, as well as introducing the grey modeling method in the case of a more exact uncertainty estimate. The modified control technology has a high-precision tracking performance and a fast convergent speed. Simulated and experimental results point out that the modified control technology can effectuate low total harmonic distortion (THD) and fast dynamic response in the presence of rectifier loads and abrupt step load changes.
      Citation: Electronics
      PubDate: 2019-04-10
      DOI: 10.3390/electronics8040419
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 420: A Data-Driven Short-Term Forecasting Model
           for Offshore Wind Speed Prediction Based on Computational Intelligence

    • Authors: Panapakidis, Michailides, Angelides
      First page: 420
      Abstract: Wind speed forecasting is an important element for the further development of offshore wind turbines. Due to its importance, many researchers have proposed different models for wind speed forecasting that differ in terms of the time-horizon of the forecast, types and number of inputs, complexity, structure, and others. Wind speed series present high nonlinearity and volatilities, and thus an effective model should successfully deal with those features. An approach to deal with the nonlinearities and volatilities is to utilize a time series processing technique such as the wavelet transform. In the present paper, an ensemble data-driven short-term wind speed forecasting model is developed, tested and applied. The term “ensemble” refers to the combination of two different predictors that run in parallel and the prediction is obtained by the predictor that leads to the lowest error. The proposed model utilizes the wavelet transform and is compared with other models that have been presented in the related literature and outperforms their accuracy. The proposed forecasting model can be used effectively for 1 min and 10 min ahead horizon wind speed predictions.
      Citation: Electronics
      PubDate: 2019-04-10
      DOI: 10.3390/electronics8040420
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 421: Switching Power Suppliers Noise Reduction
           in Ultrasound Doppler Fluid Measurements

    • Authors: Stefano Ricci
      First page: 421
      Abstract: Ultrasound Doppler techniques are widely employed in detecting the velocity of moving fluids both in medical and industrial applications. Echo Doppler electronics systems include a highly sensitive front-end suitable to processing the very low power ultrasound echoes received by the transducer. Moreover, the front-end input bandwidth typically ranges between 100 kHz and 10 MHz, which is the same frequency range where modern switching regulators work. Thus, the front-end is particularly prone to the noise produced by the suppliers that power the board itself. Electromagnetic interference (EMI) filters and spread-spectrum modulation of the switching regulator frequency help, but the results are often not optimal, and unacceptable artifacts are visible in the Doppler spectrum. In this paper a spread-spectrum modulation is proposed that concentrates the switching noise in the low-frequency range of the Doppler spectrum (e.g., 0–100 Hz). This range is removed by the high-pass clutter filter normally used in velocity Doppler investigations, thus switching noise and artifacts are eliminated. The method is verified through mathematical simulations and tested in measurements carried out with a research Doppler system. An example is presented in which the artifacts present during the investigation of a 0.4-m/s flow in a 25.4-mm diameter pipe are effectively removed by the proposed method.
      Citation: Electronics
      PubDate: 2019-04-11
      DOI: 10.3390/electronics8040421
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 422: Distributed E-Voting and E-Bidding Systems
           Based on Smart Contract

    • Authors: Raylin Tso, Zi-Yuan Liu, Jen-Ho Hsiao
      First page: 422
      Abstract: Traditional voting and bidding systems largely rely on paperwork and human resources throughout the voting process, which can incur high costs in terms of both time and money. Electronic voting and electronic bidding systems can be used to reduce costs, and many new systems have been introduced. However, most systems require a powerful and trusted third party to guarantee system integrity and security. With developments in blockchain technology, research has begun to highlight the core concept of decentralization. In this study, we introduce the first decentralized electronic voting and bidding systems based on a blockchain and smart contract. We also use cryptographic techniques such as oblivious transfer and homomorphic encryptions to improve privacy protection. Our proposed systems allow voters and bidders to participate in the opening phase and improve participant anonymity, the privacy of data transmission, and data reliability and verifiability. Moreover, compared with other electronic voting and bidding systems, our systems are safer and more efficient.
      Citation: Electronics
      PubDate: 2019-04-11
      DOI: 10.3390/electronics8040422
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 423: Developing a Real-time Monitoring
           Traceability System for Cold Chain of Tricholoma matsutake

    • Authors: Xinwu Li, Lin Yang, Yanqing Duan, Zhigang Wu, Xiaoshuan Zhang
      First page: 423
      Abstract: Tricholoma matsutake (T. matsutake) is a special type of fungus known as "the king of bacteria", and has the very high economic value. However, it is also very difficult to transport due to its corruptibility. Therefore, tracing and tracking the quality and safety of T. matsutake in the cold chain is very important and necessary. Based on changes in the cold chain environmental parameters determine the safety of T. matsutake is a viable option. This paper developed and tested a real-time monitoring traceability system (RM-TM) using emerging Internet of Things (IoT) technologies for monitoring the cold chain logistics environmental parameters of T. matsutake. Finally, system testing and evaluation have shown that RM-TM can track and monitor temperature, humidity, oxygen and carbon dioxide fluctuations in the cold chain in real-time. In addition, the collected data can be used to increase the transparency of cold chain logistics and to more effectively control quality, safety, and traceability. In general, the system evaluation results show that it is reliable and meets the requirements of users.
      Citation: Electronics
      PubDate: 2019-04-11
      DOI: 10.3390/electronics8040423
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 424: Open Source Data Logging and Data
           Visualization for an Isolated PV System

    • Authors: Bojian Jiang, M. Tariq Iqbal
      First page: 424
      Abstract: Monitoring the operation of an isolated photovoltaic (PV) system needs both data loggers and web transfer to collect the sensor data. The data includes the measurement of the voltage and current of the PV system and for local weather. The PV system in Memorial University of Newfoundland (MUN) is 5 m away from the window, where the weather data is collected. In reality, PV systems are approximately 25–50 m away from the weather sensors. It is, therefore, more meaningful to realize the sensor communications by wireless transfer than long cables, which can significantly reduce the cables of a large PV system with long distances among sensors. The PC receives all the sensor data and transfers hem to a web server (Thingspeak). A web server is applied to monitor the operation of the system instead of a local server when its users are far away from the location, even though the local server allows more frequent data logging (once per second). The data transformation between the PC and the web server must guarantee the stability and robustness of the program. The system alarm that reports the disconnection failure is also necessary to notify the users. This paper will first introduce the general system setup, then present each part of the system in detail, and finally, analyze the collected data.
      Citation: Electronics
      PubDate: 2019-04-11
      DOI: 10.3390/electronics8040424
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 425: Modeling and Analysis of Adaptive
           Temperature Compensation for Humidity Sensors

    • Authors: Xu, Feng, Xing
      First page: 425
      Abstract: In addition to being sensitive to humidity, humidity sensors with moisture sensitive elements are also sensitive to ambient temperature. The fusion of temperature and humidity data is an effective way to improve the accuracy of humidity sensors. In view of the problem of insufficient adaptive ability and poor universality in the current compensation algorithm, a piecewise processing of measured error at different temperatures by using multiple linear regression is proposed in this paper. The least squares method and back propagation (BP) neural network improved by a genetic simulated annealing algorithm (GSA-BP) were used to compensate the measured humidity data of different temperature ranges. The efficiency of the GSA-BP algorithm was tested, and the compensation function model was established. The compensation accuracy was also compared with the accuracies obtained by other methods. The experimental results show that the adaptive segmentation compensation method can significantly improve the measured error of the humidity sensor over a wide temperature range.
      Citation: Electronics
      PubDate: 2019-04-11
      DOI: 10.3390/electronics8040425
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 426: Passive multiple target indoor
           localization based on joint interference cancellation in an RFID System

    • Authors: Liu, Ma, Wang, Zhang, Yang, Wang
      First page: 426
      Abstract: Radio frequency identification (RFID) provides a simple and effective solution to the passive indoor localization. The conventional wisdom about RFID localization is using reference tags. It performs well in tag or passive single target localization. However, in the passive multiple target scenario, reference tag based localization suffers from some limitations, including the array aperture, mutual coupling of reference tags, and coherent superimposition signals. These problems are harmless and ignored in tag or passive single target localization, but degrade the performance severely in passive multiple target scenario. Therefore, in this paper, the authors propose a joint interference cancellation method to mitigate the effect of these limitations. Uniform circular array (UCA) of reference tags were used to reduce the interference of the array aperture. A carefully designed relative position of adjacent reference tags and a modified channel model were combined to reduce the mutual coupling. A virtual distributed reader antenna array was used to reduce the false positive and false negative estimations. The system was evaluated in real indoor environment using noodles and colas as targets and can work well in a smoky environment that is similar to some real industrial environments. The accuracy of target number estimation is 97.5%. The spatial resolution is about 30 cm, and the median error of 2-D multiple target localization is about 5.5 cm.
      Citation: Electronics
      PubDate: 2019-04-11
      DOI: 10.3390/electronics8040426
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 427: AgreeRelTrust—a Simple Implicit Trust
           Inference Model for Memory-Based Collaborative Filtering Recommendation
           Systems

    • Authors: Zahir, Yuan, Moniz
      First page: 427
      Abstract: Recommendation systems alleviate the problem of information overload by helping users find information relevant to their preference. Memory-based recommender systems use correlation-based similarity to measure the common interest among users. The trust between users is often used to address the issues associated with correlation-based similarity measures. However, in most applications, the trust relationships between users are not available. A popular method to extract the implicit trust relationship between users employs prediction accuracy. This method has several problems such as high computational cost and data sparsity. In this paper, addressing the problems associated with prediction accuracy-based trust extraction methods, we proposed a novel trust-based method called AgreeRelTrust. Unlike accuracy-based methods, this method does not require the calculation of initial prediction and the trust relationship is more meaningful. The collective agreements between any two users and their relative activities are fused to obtain the trust relationship.  To evaluate the usefulness of our method, we applied it to three public data sets and compared the prediction accuracy with well-known collaborative filtering methods. The experimental results show our method has large improvements over the other methods.
      Citation: Electronics
      PubDate: 2019-04-11
      DOI: 10.3390/electronics8040427
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 428: Open-Source Electronics Platforms:
           Development and Applications

    • Authors: Trung Dung Ngo
      First page: 428
      Abstract: Open-source electronics are becoming very popular with our daily educational and developmental purposes [...]
      Citation: Electronics
      PubDate: 2019-04-12
      DOI: 10.3390/electronics8040428
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 429: Design of Robust Fuzzy Logic Controller
           Based on the Levenberg Marquardt Algorithm and Fault Ride Trough
           Strategies for a Grid-Connected PV System

    • Authors: Islam, Zeb, Din, Khan, Ishfaq, Hussain, Busarello, Kim
      First page: 429
      Abstract: This paper emphasizes the design and investigation of a new optimization scheme for a grid-connected photovoltaic system (PVS) under unbalance faults. The proposed scheme includes fuzzy logic controller (FLC) based on the Levenberg–Marquardt (LM) optimization technique in coordination with bridge-type-fault-current limiter (BFCL) as the fault ride through (FRT) Strategy. The LM optimization-based control is an iterative process with a fast and robust response and is always convergent. The BFCL reduces the fault currents to rated values without compromising at ripples. A keen and critical comparison of the designed strategy is carried out with a conventionally tuned proportional-integral (PI) controller in coordination with the crowbar FRT strategy. A 100kW MATLAB/Simulink model of a photovoltaic system is used for simulation and analysis of unbalance faults at the point of common-coupling (PCC) and at 5 km away from PCC. It is found that grid-connected PVS is highly influenced by the fault type and less effected by the distribution line length. The simulation results authenticated smooth, stable, ripples with free, robust, and fault-tolerant behavior of the proposed scheme.
      Citation: Electronics
      PubDate: 2019-04-12
      DOI: 10.3390/electronics8040429
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 430: Fast Depth Intra Mode Decision Based on
           Mode Analysis in 3D Video Coding

    • Authors: Jin Young Lee
      First page: 430
      Abstract: Multiview video plus depth (MVD), which consists of a texture image and its associated depth map, has been introduced as a 3D video format, and 3D video coding, such as 3D-HEVC, was developed to efficiently compress this MVD data. However, this requires high encoding complexity because of the additional depth coding. In particular, intra coding using various prediction modes is very complicated. To reduce the complexity, we propose a fast depth intra mode decision method based on mode analysis. The proposed method adaptively reduces the number of original candidate modes in a mode decision process. Experimental results show that the proposed method achieves high performance in terms of the complexity reduction.
      Citation: Electronics
      PubDate: 2019-04-13
      DOI: 10.3390/electronics8040430
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 431: A High-Performance Elliptic Curve
           Cryptographic Processor of SM2 over GF(p)

    • Authors: Xianghong Hu, Xin Zheng, Shengshi Zhang, Weijun Li , Shuting Cai , Xiaoming Xiong
      First page: 431
      Abstract: Elliptic curve cryptography (ECC) is widely used in practical applications because ECC has far fewer bits for operands at the same level of security than other public-key cryptosystems such as RSA. The performance of an ECC processor is usually determined by modular multiplication (MM) and point multiplication (PM) operations. For recommended prime field, MM operation can consist of multiplication and fast reduction operations. In this paper, a 256-bit multiplication operation is implemented by a 129-bit (half-word) multiplier using Karatsuba–Ofman multiplication algorithm. The fast reduction is a modulo operation, which gets 512-bit input data from multiplication and outputs a 256-bit result ( 0 ≤ Z < p ) . We propose a two-stage fast reduction algorithm (TSFR) over SCA-256 prime field, which can obtain an intermediate result of 0 ≤ Z < 2 p instead of 0 ≤ Z < 14 p in traditional algorithm, avoiding a lot of repetitive subtraction operations. The PM operation is implemented in width nonadjacent form (NAF) algorithm and its operational schedules are improved to increase the parallelism of multiplication and fast reduction operations. Synthesized with a 0.13 μ m complementary metal oxide semiconductor (CMOS) standard cell library, the proposed processor costs an area of 280 k gates and PM operation takes 0.057 ms at the frequency of 250 MHz. The design is also implemented on Xilinx Virtex-6 platform, which consumes 27.655 k LUTs and takes 0.37 ms to perform one 256-bit PM operation, attaining six times speed-up over the state-of-the-art. The processor makes a tradeoff between area and performance, thus it is better than other methods.
      Citation: Electronics
      PubDate: 2019-04-14
      DOI: 10.3390/electronics8040431
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 432: Optimal Physical Implementation of
           Radiation Tolerant High-Speed Digital Integrated Circuits in
           Deep-Submicron Technologies

    • Authors: Jeffrey Prinzie, Karel Appels, Szymon Kulis
      First page: 432
      Abstract: This paper presents a novel scalable physical implementation method for high-speed Triple Modular Redundant (TMR) digital integrated circuits in radiation-hard designs. The implementation uses a distributed placement strategy compared to a commonly used bulk 3-bank constraining method. TMR netlist information is used to optimally constrain the placement of both sequential cells and combinational cells. This approach significantly reduces routing complexity, net lengths and dynamic power consumption with more than 60% and 20% respectively. The technique was simulated in a 65 nm Complementary Metal-Oxide Semiconductor (CMOS) technology.
      Citation: Electronics
      PubDate: 2019-04-14
      DOI: 10.3390/electronics8040432
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 433: Visible Light Communication System Based
           on Software Defined Radio: Performance Study of Intelligent Transportation
           and Indoor Applications

    • Authors: Radek Martinek, Lukas Danys, Rene Jaros
      First page: 433
      Abstract: In this paper, our first attempt at visible light communication system, based on software defined radio (SDR) and implemented in LabVIEW is introduced. This paper mainly focuses on two most commonly used types of LED lights, ceiling lights and LED car lamps/tail-lights. The primary focus of this study is to determine the basic parameters of real implementation of visible light communication (VLC) system, such as transmit speed, communication errors (bit-error ratio, error vector magnitude, energy per bit to noise power spectral density ratio) and highest reachable distance. This work focuses on testing various multistate quadrature amplitude modulation (M-QAM). We have used Skoda Octavia III tail-light and Phillips indoor ceiling light as transmitters and SI PIN Thorlabs photodetector as receiver. Testing method for each light was different. When testing ceiling light, we have focused on reachable distance for each M-QAM variant. On the other side, Octavia tail-light was tested in variable nature conditions (such as thermal turbulence, rain, fog) simulated in special testing box. This work will present our solution, measured parameters and possible weak spots, which will be adjusted in the future.
      Citation: Electronics
      PubDate: 2019-04-15
      DOI: 10.3390/electronics8040433
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 434: A Parasitic Resonator-Based Diamond-Shaped
           Microstrip Antenna for Microwave Imaging Applications

    • Authors: Md Zulfiker Mahmud, Md Tarikul. Islam, Ali F. Almutairi, Md Samsuzzaman, U.K. Acharjee, Mohammad Tariqul Islam
      First page: 434
      Abstract: This study proposes a new parasitic resonator-based diamond-shaped microstrip patch antenna for ultra-wideband microwave imaging applications. The antenna consists of a diamond-shaped radiating patch, partial ground plane, and four-star shape parasitic elements. The use of parasitic elements improves the antenna performance in terms of the bandwidth and gain. The proposed prototype has a compact dimension of 30 × 25 × 1.6 mm3. The antenna achieves an overall bandwidth (S11<-10dB) of 7.6 GHz (2.7–10.3 GHz) with more than 4 dBi realized gain and 80% efficiency across the radiating bandwidth. The modified structures of the design extended the usable upper frequency from 9.7 GHz to 10.3 GHz, and the lower frequency is decreased from 3.4 GHz to 2.7 GHz with maintaining the omnidirectional radiation pattern. The design and simulation of the antenna are performed in the 3D electromagnetic simulator CST Microwave Studio. The proposed antenna is used for breast phantom measurement system to analyze the variation of backscattering signal and transmit-received pulses. The observation during the analysis of the numerical and measured data reveals that the designed antenna is a suitable candidate for ultra-wideband (UWB)-based microwave imaging applications.
      Citation: Electronics
      PubDate: 2019-04-16
      DOI: 10.3390/electronics8040434
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 435: Implementation of ARINC 659 Bus Controller
           for Space-Borne Computers

    • Authors: Shuang Jiang, Shibin Liu, Chenguang Guo, Xu Fan, Teng Ma, Prayag Tiwari
      First page: 435
      Abstract: As one of the key technologies of Honeywell, the aeronautical radio incorporated (ARINC) 659 bus is popular in current space-borne computers. However, Honeywell does not design ARINC 659 bus controller separately, and there are only a few papers about FPGA-based ARINC 659 bus controllers. Accordingly, to promote the extremely high performance needs of space-borne computers, this paper designs an ARINC 659 bus controller chip which integrates two independent bus interface units (BIUs), one 8-bit MCU, and several peripheral interfaces (i.e., UART, SPI, and I2C). Because the two BIUs are identical and mutually checked, the symmetry problem is emphatically dealt with in the design of this bus controller, and effective timing convergence is realized, which makes the bus controller work reliably and stably. In addition, due to the circuit’s large scale, design for testability (DFT) is also considered. Accordingly, on-chip clock (OCC) and scanning compression test technique are used to realize the at-speed test and shorten the test time, respectively.
      Citation: Electronics
      PubDate: 2019-04-16
      DOI: 10.3390/electronics8040435
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 436: Multi-User Linear Equalizer and Precoder
           Scheme for Hybrid Sub-Connected Wideband Systems

    • Authors: Daniel Castanheira, Sara Teodoro, Ricardo Simões, Adão Silva, Atilio Gameiro
      First page: 436
      Abstract: Millimeter waves and massive multiple-input multiple output (MIMO) are two promising key technologies to achieve the high demands of data rate for the future mobile communication generation. Due to hardware limitations, these systems employ hybrid analog–digital architectures. Nonetheless, most of the works developed for hybrid architectures focus on narrowband channels, and it is expected that millimeter waves be wideband. Moreover, it is more feasible to have a sub-connected architecture than a fully connected one, due to the hardware constraints. Therefore, the aim of this paper is to design a sub-connected hybrid analog–digital multi-user linear equalizer combined with an analog precoder to efficiently remove the multi-user interference. We consider low complexity user terminals employing pure analog precoders, computed with the knowledge of a quantized version of the average angles of departure of each cluster. At the base station, the hybrid multi-user linear equalizer is optimized by using the bit-error-rate (BER) as a metric over all the subcarriers. The analog domain hardware constraints, together with the assumption of a flat analog equalizer over the subcarriers, considerably increase the complexity of the corresponding optimization problem. To simplify the problem at hand, the merit function is first upper bounded, and by leveraging the specific properties of the resulting problem, we show that the analog equalizer may be computed iteratively over the radio frequency (RF) chains by assigning the users in an interleaved fashion to the RF chains. The proposed hybrid sub-connected scheme is compared with a fully connected counterpart.
      Citation: Electronics
      PubDate: 2019-04-16
      DOI: 10.3390/electronics8040436
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 437: A Highly Linear Low-Noise Transimpedance
           Amplifier for Indoor Fiber-Wireless Remote Antenna Units

    • Authors: Guillermo Royo, Antonio D. Martinez-Perez, Carlos Sanchez-Azqueta, Concepcion Aldea, Santiago Celma
      First page: 437
      Abstract: This article presents an optimized design of a low-noise transimpedance amplifier (TIA) with high linearity for use in the downlink receiver of a remote antenna unit (RAU). The aim of this design is to be used in a cost-effective indoor distributed antenna system (DAS) for WLAN transmission using a mixed fiber-wireless system. The circuit topology consists of a fully differential shunt–shunt feedback TIA with digitally programmable transimpedance. An open-loop gain compensation technique is used to maintain stability and constant bandwidth (BW). The TIA has been fabricated in 65 nm CMOS technology with a 1.2 V voltage supply. The total power consumption of the TIA is 6 mW. A complete electrical and optical characterization with a 1550 nm PIN photodiode has been performed to demonstrate the reliable 54 Mb/s 802.11a WLAN transmission achieved with an error vector magnitude (EVM) lower than 3% for a 20 dB optical input range.
      Citation: Electronics
      PubDate: 2019-04-16
      DOI: 10.3390/electronics8040437
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 438: Impedance-Source DC-to-AC/DC Converter

    • Authors: R. Sivapriyan, D. Elangovan
      First page: 438
      Abstract: This article presents a novel impedance-source-based direct current (DC)-to-alternating current (AC)/DC converter (Z-Source DAD Converter). The Z-Source DAD converter converts the input DC voltage into AC or DC with buck or boost in the load voltage. This Z-Source DAD conversion circuit is a single-stage power conversion system. This converter circuit converts the input DC voltage into variable-magnitude output DC voltage or converts the DC voltage into a variable-magnitude output AC voltage. The higher voltage magnitude in boost mode can be controlled by controlling the shoot-through (ST) state timing of the converter. MATLAB-Simulink simulation and microcontroller-based hardware circuit results are presented to demonstrate power conversion with the buck and boost features of the Z-Source DAD converter for both types of output voltages. The simulation and experimental results show that the Z-Source DAD converter converts the given DC supply into AC or DC with buck or boost in the output load voltage.
      Citation: Electronics
      PubDate: 2019-04-16
      DOI: 10.3390/electronics8040438
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 439: Analysis of a DC Converter with Low
           Primary Current Loss and Balance Voltage and Current

    • Authors: Lin
      First page: 439
      Abstract: A dc/dc pulse width modulation (PWM) circuit was investigated to realize the functions of reduced primary current loss and balanced voltage and current distribution. In the presented dc/dc converter, two full bridge pulse width modulation circuits were used with the series/parallel connection on the high-voltage/low-voltage side. The flying capacitor was adopted on the input side to achieve voltage balance on input split capacitors. The magnetic coupling element was employed to achieve current sharing between two parallel circuits. A capacitor-diode passive circuit was adopted to lessen the primary current at the commutated interval. The phase-shifted duty cycle control approach was employed to regulate load voltage and implement soft switching characteristics of power metal-oxide-semiconductor field-effect transistors (MOSFETs). Finally, the experimental results using a 1.68 kW prototype converter were obtained to confirm the performance and feasibility of the studied circuit topology.
      Citation: Electronics
      PubDate: 2019-04-17
      DOI: 10.3390/electronics8040439
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 440: A Compact Wideband SIW Bandpass Filter
           with Wide Stopband and High Selectivity

    • Authors: Huang, Yuan
      First page: 440
      Abstract: A novel method to design a wideband substrate integrated waveguide (SIW) bandpass filter (BPF) with compact size, wide stopband and high selectivity is presented. In this method some unique electromagnetic band-gap (EBG) cells are periodically etched on the top layer of SIW to realize a wide passband propagating below the equivalent waveguide cutoff frequency. By changing the configuration of EBG cells, undesired harmonics in upper stopband can be suppressed and a wideband BPF with wide stopband can be obtained. By symmetrically loading two complementary split ring resonators (CSRRs) on the tapered gradient lines of the input/output ports, a transmission zero near the passband can be introduced, and it makes the frequency selectivity of upper sideband improve significantly. As a verification, a wideband SIW BPF with a 3.02 GHz absolute bandwidth (ABW) and a 64.7% fractional bandwidth (FBW) centered at 4.67 GHz is designed, simulated, manufactured, and measured. The results of the experiment and simulation are in good agreement.
      Citation: Electronics
      PubDate: 2019-04-17
      DOI: 10.3390/electronics8040440
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 441: WSMS: Wearable Stress Monitoring System
           based on IoT Multi-Sensor Platform for Living Sheep Transportation

    • Authors: Cui, Zhang, Li, Luo, Zhang, Fu
      First page: 441
      Abstract: Farming herdsmen, sheep dealers, and veterinarians are increasingly interested in continuously monitoring sheep basic physiological characteristics (such as the heart rate and skin temperature) outside the laboratory environment, with the aim of identifying the physiological links between stress, uncomfortable, excitement, and other pathological states. This paper proposes a non-invasive Wearable Stress Monitoring System (WSMS) with PhotoPlethysmoGram (PPG), Infrared Temperature Measurement (ITM), and Inertial Measurement Units (IMU) that aimed to remotely and continuously monitor the stress signs of sheep during transportation. The purpose of this study was implemented by following the multi-dimensional sensing platform to identify more pressure information. The designed WSMS showed sufficient robustness in recording and transmitting sensing data of physiology and environment during transport. The non-contact and non-destructive monitoring method that was proposed in this paper was helpful in minimizing the effects of sheep stress load.
      Citation: Electronics
      PubDate: 2019-04-17
      DOI: 10.3390/electronics8040441
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 442: A Novel Approach towards Resource
           Auto-Registration and Discovery of Embedded Systems Based on DNS

    • Authors: Khudoyberdiev, Jin, Kim
      First page: 442
      Abstract: The Internet of Things (IoT) is expected to deliver a whole range of new services to all parts of our society, and improve the way we work and live. The challenges within the Internet of Things are often related to interoperability, device resource constraints, a device to device connection and security. One of the essential elements of identification for each Internet of Things devices is the naming system and addresses. With this naming system, Internet of Things devices can be able to be discoverable by users. In this paper, we propose the IoT resource auto-registration and accessing indoor services based on Domain Name System (DNS) in the Open Connectivity Foundation (OCF) environment. We have used the Internet of Things Platform and DNS server for IoT Resource auto-registration and discovery in the Internet Protocol version 4 (IPv4). An existing system called Domain Name Auto-Registration in Internet Protocol version 6 can be used for Internet of Things devices for auto-registration and resource discovery. However, this system is not acceptable in the existing internet networks, because the highest percentage of the networks on the Internet are configured in Internet Protocol version 4. Through the proposed auto-registration system, clients can be able to discover the resources and access the services in the OCF network. Constrained Application Protocol (CoAP) is utilized for the IoT device auto-registration and accessing the services in the OCF network.
      Citation: Electronics
      PubDate: 2019-04-17
      DOI: 10.3390/electronics8040442
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 443: A Hierarchical Cooperative Mission
           Planning Mechanism for Multiple Unmanned Aerial Vehicles

    • Authors: Zhe Zhao, Jian Yang, Yifeng Niu, Yu Zhang, Lincheng Shen
      First page: 443
      Abstract: In this paper, the cooperative multi-task online mission planning for multiple Unmanned Aerial Vehicles (UAVs) is studied. Firstly, the dynamics of unmanned aerial vehicles and the mission planning problem are studied. Secondly, a hierarchical mechanism is proposed to deal with the complex multi-UAV multi-task mission planning problem. In the first stage, the flight paths of UAVs are generated by the Dubins curve and B-spline mixed method, which are defined as “CBC)” curves, where “C” stands for circular arc and “B” stands for B-spline segment. In the second stage, the task assignment problem is solved as multi-base multi-traveling salesman problem, in which the “CBC” flight paths are used to estimate the trajectory costs. In the third stage, the flight trajectories of UAVs are generated by using Gaussian pseudospectral method (GPM). Thirdly, to improve the computational efficiency, the continuous and differential initial trajectories are generated based on the “CBC” flight paths. Finally, numerical simulations are presented to demonstrate the proposed approach, the designed initial solution search algorithm is compared with existing methods. These results indicate that the proposed hierarchical mission planning method can produce satisfactory mission planning results efficiently.
      Citation: Electronics
      PubDate: 2019-04-18
      DOI: 10.3390/electronics8040443
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 444: Early Output Quasi-Delay-Insensitive Array
           Multipliers

    • Authors: Balasubramanian, Maskell, Naayagi, Mastorakis
      First page: 444
      Abstract: Multiplication is a widely used arithmetic operation in microprocessing and digital signal processing applications, and multiplication is realized using a multiplier. This article presents the quasi-delay-insensitive (QDI) early output versions of recently reported indicating asynchronous array multipliers. Delay-insensitive dual-rail encoding is used for data representation and processing, and 4-phase return-to-zero (RTZ) and return-to-one (RTO) handshake protocols are used for data communication. Many QDI array multipliers were realized using a 32/28 nm complementary metal oxide semiconductor (CMOS) technology. Compared to the optimum indicating array multiplier, the proposed optimum early output array multiplier achieves a 6.2% reduction in cycle time and a 7.4% reduction in power-cycle time product (PCTP) with respect to RTZ handshaking, and a 7.6% reduction in cycle time and an 8.8% reduction in PCTP with respect to RTO handshaking without an increase in the area. The simulation results also convey that the RTO handshaking is preferable to the RTZ handshaking for the optimum implementation of QDI array multipliers.
      Citation: Electronics
      PubDate: 2019-04-18
      DOI: 10.3390/electronics8040444
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 445: Area-Efficient Embedded Resistor-Triggered
           SCR with High ESD Robustness

    • Authors: Hou, Du, Yang, Liu, Liu
      First page: 445
      Abstract: The trigger voltage of the direct-connected silicon-controlled rectifier (DCSCR) was effectively reduced for electrostatic discharge (ESD) protection. However, a deep NWELL (DNW) is required to isolate PWELL from P-type substrate (PSUB) in DCSCR, which wastes part of the layout area. An area-efficient embedded resistor-triggered silicon-controlled rectifier (ERTSCR) is proposed in this paper. As verified in a 0.3-μm CMOS process, the proposed ERTSCR exhibits lower triggering voltage due to series diode chains and embedded deep n-well resistor in the trigger path. Additionally, the proposed ERTSCR has a failure current of more than 5 A and a corresponding HBM ESD robustness of more than 8 KV. Furthermore, compared with the traditional DCSCR, to sustain the same ESD protection capability, the proposed ERTSCR will consume 10% less silicon area by fully utilizing the lateral dimension in the deep n-well extension region, while the proposed ERTSCR has a larger top metal width.
      Citation: Electronics
      PubDate: 2019-04-18
      DOI: 10.3390/electronics8040445
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 446: Using Different Ions in the Hydrothermal
           Method to Enhance the Photoluminescence Properties of Synthesized
           ZnO-Based Nanowires

    • Authors: Ya-Fen Wei, Wen-Yaw Chung, Cheng-Fu Yang, Jei-Ru Shen, Chih-Cheng Chen
      First page: 446
      Abstract: ZnO films with a thickness of ~200 nm were deposited on SiO2/Si substrates as the seed layer. Then Zn(NO3)2-6H2O and C6H12N4 containing different concentrations of Eu(NO3)2-6H2O or In(NO3)2-6H2O were used as precursors, and a hydrothermal process was used to synthesize pure ZnO as well as Eu-doped and In-doped ZnO nanowires at different synthesis temperatures. X-ray diffraction (XRD) was used to analyze the crystallization properties of the pure ZnO and the Eu-doped and In-doped ZnO nanowires, and field emission scanning electronic microscopy (FESEM) was used to analyze their surface morphologies. The important novelty in our approach is that the ZnO-based nanowires with different concentrations of Eu3+ and In3+ ions could be easily synthesized using a hydrothermal process. In addition, the effect of different concentrations of Eu3+ and In3+ ions on the physical and optical properties of ZnO-based nanowires was well investigated. FESEM observations found that the undoped ZnO nanowires could be grown at 100 °C. The third novelty is that we could synthesize the Eu-doped and In-doped ZnO nanowires at temperatures lower than 100 °C. The temperatures required to grow the Eu-doped and In-doped ZnO nanowires decreased with increasing concentrations of Eu3+ and In3+ ions. XRD patterns showed that with the addition of Eu3+ (In3+), the diffraction intensity of the (002) peak slightly increased with the concentration of Eu3+ (In3+) ions and reached a maximum at 3 (0.4) at%. We show that the concentrations of Eu3+ and In3+ ions have considerable effects on the synthesis temperatures and photoluminescence properties of Eu3+-doped and In3+-doped ZnO nanowires.
      Citation: Electronics
      PubDate: 2019-04-18
      DOI: 10.3390/electronics8040446
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 447: Rolling 3D Laplacian Pyramid Video Fusion

    • Authors: Rade Pavlović, Vladimir Petrović
      First page: 447
      Abstract: In this paper, we present a novel algorithm for video fusion of multi-sensor sequences applicable to real-time night vision systems. We employ the Laplacian pyramid fusion of a block of successive frames to add temporal robustness to the fused result. For the fusion rule, we first group high and low frequency levels of the decomposed frames in the block from both input sensor sequences. Then, we define local space-time energy measure to guide the selection based fusion process in a manner that achieves spatio-temporal stability. We demonstrate our approach on several well-known multi-sensor video fusion examples with varying contents and target appearance and show its advantage over conventional video fusion approaches. Computational complexity of the proposed methods is kept low by the use of simple linear filtering that can be easily parallelised for implementation on general-purpose graphics processing units (GPUs).
      Citation: Electronics
      PubDate: 2019-04-19
      DOI: 10.3390/electronics8040447
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 448: Performance Analysis of a User Selection
           Protocol in Cooperative Networks with Power Splitting Protocol-Based
           Energy Harvesting Over Nakagami-m/Rayleigh Channels

    • Authors: Tan N. Nguyen, Minh Tran, Thanh-Long Nguyen, Duy-Hung Ha, Miroslav Voznak
      First page: 448
      Abstract: In this work, the system performance analysis of cooperative networks with power splitting protocol-based energy harvesting (EH) over Nakagami-m/Rayleigh channels is proposed. The exact-form expressions of the outage probability (OP) and ergodic capacity (EC) is demonstrated and derived. Using the proposed probabilistic models for wireless channels, we derive OP and EC as a research result. Finally, we conduct Monte Carlo simulations to verify a system performance analysis of the proposed system. The research results demonstrate the effectiveness of EH in the network over Nakagami-m/Rayleigh channels.
      Citation: Electronics
      PubDate: 2019-04-19
      DOI: 10.3390/electronics8040448
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 449: A Capacitor Voltage Balancing Approach
           Based on Mapping Strategy for MMC Applications

    • Authors: Ricco, Mathe, Hammami, Franco, Rossi, Teodorescu
      First page: 449
      Abstract: This paper proposes a new strategy to achieve balanced capacitor voltages in modular multilevel converters. Among the possible solutions, centralized arm control approaches are often adopted. These methods require a balancing technique based on a sorted list of the sub-modules according to their capacitor voltages. In order to achieve the aforementioned sorted list, different algorithms have been proposed in literature, such as: Sorting algorithms, max/min approaches, etc. However, the sorting algorithms require a long execution time, while the max/min approaches affect the converter dynamic response during faults. To overcome these issues, a new mapping strategy providing a quasi-sorted list is proposed in this paper. The suggested method is compared in simulation with both the classical bubble sorting algorithm, and the max/min method during both normal and faulty conditions. Moreover, the three methods have been implemented in a Xilinx Zynq-7000 System-on-Chip (SoC) device, in order to analyze the corresponding execution time and the required computational effort. Hardware-in-the-loop results are presented for demonstrating the superior performance of the proposed balancing strategy.
      Citation: Electronics
      PubDate: 2019-04-19
      DOI: 10.3390/electronics8040449
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 450: A Privacy-Preserving Authentication and
           Key Agreement Scheme with Deniability for IoT

    • Authors: Yousheng Zhou, Tong Liu, Fei Tang, Feng Wang, Magara Tinashe
      First page: 450
      Abstract: User authentication for the Internet of Things (IoT) is a vital measure as it consists of numerous unattended connected devices and sensors. For security, only the user authenticated by the gateway node can access the real-time data gathered by sensor nodes. In this article, an efficient privacy-preserving authentication and key agreement scheme for IoT is developed which enables the user, the gateway node and sensor nodes to authenticate with each other. Only the trusted gateway node can determine the real identity of user; however, no other entities can get information about user’ identity by just intercepting all exchanged messages during authentication phase. The gateway cannot prove the received messages from the sender to a third party, and thus preserving the privacy of the sender. The correctness of the proposed scheme is proved to be feasible by using BAN logic, and its security is proved under the random oracle model. The execution time of the proposed scheme is evaluated and compared with existing similar schemes, and the results demonstrate that our proposed scheme is more efficient and applicable for IoT applications.
      Citation: Electronics
      PubDate: 2019-04-19
      DOI: 10.3390/electronics8040450
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 451: Multi-Channel Optoelectronic Measurement
           System for Soil Nutrients Analysis

    • Authors: Liuzheng Ma, Zhenfeng Li, Zephania Birech, Shixin Li, Yatao Yang, Wei Zhang, Jiandong Hu
      First page: 451
      Abstract: To solve the problems that occur when farmers overuse chemical fertilizers, it is necessary to develop rapid and efficient portable measurement systems for the detection and quantification of nitrogen (N), phosphorus (P), and potassium (K) in soil. Challenges arise from the use of currently available portable instruments which only have a few channels, namely measurement and the reference channels. We report on a home-built, multichannel, optoelectronic measurement system with automatically switching light sources for the detection of N, P, K content in soil samples. This optoelectronic measurement system consists of joint LED light sources with peak emission wavelengths of 405 nm, 660 nm, and 515 nm, a photodiode array, a circuit board with a microcontroller unit (MCU), and a liquid-crystal display (LCD) touch screen. The straightforward principle for rapid detection of the extractable nutrients (N, P, K) was well-established, and characterization of the designed measurement system was done. Using this multi-channel measurement system, available nutrients extracted from six soil samples could be measured simultaneously. The absorbance compensation, concentration calibration, and nutrition measurements were performed automatically to achieve high consistency across six channels. The experimental results showed that the cumulative relative standard deviations of 1.22%, 1.27%, and 1.00% were obtained from six channels with known concentrations of standard solutions, respectively. The coefficients of correlation for the detection of extracted nutrients of N, P, K content in soil samples using both the proposed method and conventional lab-based method were 0.9010, 0.9471, and 0.8923, respectively. Experimental results show that this optoelectronic measurement system can perform the measurement of N, P, K contents of six soil samples simultaneously and may be used as an actual tool in determining nutrients in soil samples with an improvement in detection efficiency.
      Citation: Electronics
      PubDate: 2019-04-20
      DOI: 10.3390/electronics8040451
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 452: Autonomous Control of Unmanned Aerial
           Vehicles

    • Authors: Victor M. Becerra
      First page: 452
      Abstract: Unmanned aerial vehicles (UAVs) are being increasingly used in different applications in both military and civilian domains [...]
      Citation: Electronics
      PubDate: 2019-04-22
      DOI: 10.3390/electronics8040452
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 453: A Vehicle Type Dependent Car-following
           Model Based on Naturalistic Driving Study

    • Authors: Ping Wu, Feng Gao, Keqiang Li
      First page: 453
      Abstract: In this paper, a car-following model considering the preceding vehicle type is proposed to describe the longitudinal driving behavior closer to reality. Based on the naturalistic driving data sampled in real traffic for more than half a year, the relation between ego vehicle velocity and relative distance was analyzed by a multi-variable Gaussian Mixture model, from which it is found that the driver following behavior is influenced by the type of leading vehicle. Then a Hidden Markov model was designed to identify the vehicle type. This car-following model was trained and tested by using the naturalistic driving data. It can identify the leading vehicle type, i.e., passenger car, bus, and truck, and predict the ego vehicle velocity and relative distance based on a series of limited historical data in real time. The experimental validation results show that the identification accuracy of vehicle type under the static and dynamical conditions are 96.6% and 83.1%, respectively. Furthermore, comparing the results with the well-known collision avoidance model and intelligent driver model show that this new model is more accurate and can be used to design advanced driver assist systems for better adaptability to traffic conditions.
      Citation: Electronics
      PubDate: 2019-04-23
      DOI: 10.3390/electronics8040453
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 454: Modulation Strategy with a Minimal Number
           of Commutations for a Five-Level H-Bridge NPC Inverter

    • Authors: Becker, Jamshidpour, Poure, Saadate
      First page: 454
      Abstract: In this paper, a so-called OPTimized Pulse Width Modulation (OPT-PWM) strategy with a minimal number of commutations for a multilevel converter (MC) is proposed. The principle is based on the reduction of the number of switch commutations by removing the unnecessary ones for each voltage level transition. The OPT-PWM strategy is applied to a five-level H-Bridge Neutral Point Clamped (HB-5L-NPC) inverter. A specific block based on a state machine is added to conventional modulation techniques to perform the transitions from a given voltage level to another one via the best trajectory with a minimal number of commutations. The principle of this additional block can be applied to any modulation technique. In this paper, the proposed strategy is validated first by simulation and then through experimental tests.
      Citation: Electronics
      PubDate: 2019-04-23
      DOI: 10.3390/electronics8040454
      Issue No: Vol. 8, No. 4 (2019)
       
  • Electronics, Vol. 8, Pages 355: Active and Passive Haptic Perception of
           Shape: Passive Haptics Can Support Navigation

    • Authors: José-Luis Rodríguez, Ramiro Velázquez, Carolina Del-Valle-Soto, Sebastián Gutiérrez, Jorge Varona, Josué Enríquez-Zarate
      First page: 355
      Abstract: Real-time haptic interactions occur under two exploration modes: active and passive. In this paper, we present a series of experiments that evaluate the main perceptual characteristics of both exploration modes. In particular, we focus on haptic shape recognition as it represents a fundamental task in many applications using haptic environments. The results of four experiments conducted with a group of 10 voluntary subjects show that the differences in motor activity between active and passive haptics ease the perception of surfaces for the first case and the perception of pathways for the latter. In addition, the guidance nature of passive haptics makes the pathway direction easy to recognize. This work shows that this last observation could find application in more challenging tasks such as navigation in space.
      Citation: Electronics
      PubDate: 2019-03-23
      DOI: 10.3390/electronics8030355
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 356: Exponential Synchronization in Inertial
           Neural Networks with Time Delays

    • Authors: Liang Ke, Wanli Li
      First page: 356
      Abstract: In this paper, exponential synchronization for inertial neural networks with time delays is investigated. First, by introducing a directive Lyapunov functional, a sufficient condition is derived to ascertain the global exponential synchronization of the drive and response systems based on feedback control. Second, by introducing a variable substitution, the second-order differential equation is transformed into a first-order differential equation. As such, a new Lyapunov functional is constructed to formulate a novel global exponential synchronization for the systems under study. The two obtained sufficient conditions complement each other and are suitable to be applied in different cases. Finally, two numerical examples are given to illustrated the effectiveness of the proposed theoretical results.
      Citation: Electronics
      PubDate: 2019-03-24
      DOI: 10.3390/electronics8030356
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 357: Selecting Ultracapacitors for Smoothing
           Voltage Deviations in Local Grids Fed by Transformer with Tap-Changer and
           Distributed PV Facilities

    • Authors: Sorkin, Farber, Averbukh
      First page: 357
      Abstract: Widespread use of photovoltaic (PV) small and middle-power plants close or inside existing townships and villages may cause significant deviations of the grid voltage. Owing to the oscillation of solar irradiation and corresponding power flows these voltage instabilities can damage equipment and must be prevented. Designated for the voltage regulation tap-changers in distribution transformers located in a significant distance of such settlements have a sluggish response time. As a possible answer for their delay is the smoothing energy of flows in PV power installation by intermittent capacitor low-pass filtering (LPF) located near those PV facilities. The application of ultracapacitors (UC) for LPF is remarkable due to their sustainability and relatively low costs of energy storage. The parameters selection of such appliances is a well-designed procedure for linear circuits. However, DC–AC inverters in PV facilities are represented by a power (instead of a voltage) source. As a result, the total circuit including such LPF becomes a non-linear and its transient process and consequently, its efficiency is difficult to assess requiring each time of development the UC storage an application complex numerical procedure. Engineers are usual to work with linear circuits that are describing fine by a time constant is designated as a multiplication of a capacitance times load equivalent resistance. In the case of PV DC–AC inverters, such an approach can be applied as well but a value of a time constant should be corrected. Considering a significant cost of UC storage, the non-optimal selection of a correcting coefficient may cause considerable loses. Submitted in the presented article is an original approximation procedure giving an efficiently approachable technique to select correcting coefficient for describing non-linear dynamic process by its linear analog. This way the development low-pass UC filtering in electrical systems with PV plants becomes more efficient and simpler task.
      Citation: Electronics
      PubDate: 2019-03-24
      DOI: 10.3390/electronics8030357
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 358: Sparse-Based Millimeter Wave Channel
           Estimation With Mutual Coupling Effect

    • Authors: Zhenxin Cao, Haiyang Geng, Zhimin Chen, Peng Chen
      First page: 358
      Abstract: The imperfection of antenna array degrades the communication performance in the millimeter wave (mmWave) communication system. In this paper, the problem of channel estimation for the mmWave communication system is investigated, and the unknown mutual coupling (MC) effect between antennas is considered. By exploiting the channel sparsity in the spatial domain with mmWave frequency bands, the problem of channel estimation is converted into that of sparse reconstruction. The MC effect is described by a symmetric Toeplitz matrix, and the sparse-based mmWave system model with MC coefficients is formulated. Then, a two-stage method is proposed by estimating the sparse signals and MC coefficients iteratively. Simulation results show that the proposed method can significantly improve the channel estimation performance in the scenario with unknown MC effect and the estimation performance for both direction of arrival (DOA) and direction of departure (DoD) can be improved by about 8 dB by reducing the MC effect about 4 dB.
      Citation: Electronics
      PubDate: 2019-03-25
      DOI: 10.3390/electronics8030358
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 359: IoToF: A Long-Reach Fully Passive Low-Rate
           Upstream PHY for IoT over Fiber

    • Authors: Camilo A. R. Díaz, Cátia Leitão, Carlos A. Marques, Nélia Alberto, M. Fátima Domingues, Tiago Ribeiro, Maria J. Pontes, Anselmo Frizera, Paulo F.C. Antunes, Paulo S. André, Moisés R.N. Ribeiro
      First page: 359
      Abstract: Internet of things (IoT) devices heavily rely on wireless connectivity. There are intrinsic overlooked limitations such as reach, availability, security and safety vulnerabilities closely associated with wireless solutions. Wired connectivity is the alternative to tackle those issues, and optical fibers directly connecting IoT devices could provide them unique features such as huge bandwidth, long reach, signal integrity and high security grade for the transmitted information. Nevertheless, it can be prohibitive for IoT devices which are power hungry and have costly electrical-to-optical conversions. In this paper, first, a niche is identified for IoT over fiber (IoToF) based on fully passive optical solutions for long reach upstream of low data rate optical connectivity over dark fibers. Then, we proposed, implemented and characterized a prototype physical connectivity (PHY) based on fiber Bragg grating (FBG) low-cost acousto-optic modulation at IoT devices and respective optical edge-filtering as wavelength discriminator at the receiver. Finally, we performed an experimental demonstration of upstream data communication based on simple M-ary frequency-shift keying (FSK), with baud rate of 300 bps transmitted over 30 km range. In terms of data rate and reach for niche applications, IoToF can outperform traditional wireless technologies, such as Sigfox or LoRa. IoToF will enable monitoring urban areas with scarce and polluted spectrum, industrial areas requiring intrinsic safety, and upstreaming data from IoT devices in remote locations with unfavorable wireless propagation but with dark fibers available.
      Citation: Electronics
      PubDate: 2019-03-25
      DOI: 10.3390/electronics8030359
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 360: Reducing Unnecessary Alerts in Pedestrian
           Protection Systems Based on P2V Communications

    • Authors: Ignacio Soto, Felipe Jimenez, Maria Calderon, Jose E. Naranjo, Jose J. Anaya
      First page: 360
      Abstract: There are different proposals in the literature on how to protect pedestrians using warning systems to alert drivers of their presence. They can be based on onboard perception systems or wireless communications. The evaluation of these systems has been focused on testing their ability to detect pedestrians. A problem that has received much less attention is the possibility of generating too many alerts in the warning systems. In this paper, we propose and analyze four different algorithms to take the decision on generating alerts in a warning system that is based on direct wireless communications between vehicles and pedestrians. With the algorithms, we explore different strategies to reduce unnecessary alerts. The feasibility of the implementation of the algorithms was evaluated with a deployment using real equipment, and tests were carried out to verify their behavior in real scenarios. The ability of each algorithm to reduce unnecessary alerts was evaluated with realistic simulations in an urban scenario, using a traffic simulator with vehicular and pedestrian flows. The results show the importance of tackling the problem of driver overload in warning systems, and that it is not straightforward to predict the load of alerts generated by an algorithm in a large-scale deployment, in which there are multiple interactions between vehicles and pedestrians.
      Citation: Electronics
      PubDate: 2019-03-25
      DOI: 10.3390/electronics8030360
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 361: The Improved Division-Less MT-Type
           Velocity Estimation Algorithm for Low-Cost FPGAs

    • Authors: Aleš Hace
      First page: 361
      Abstract: Advanced motion control applications require smooth and highly accurate high-bandwidth velocity feedback, which is usually provided by an incremental encoder. Furthermore, high sampling rates are also demanded in order to achieve cutting-edge system performance. Such control system performance with high accuracy can be achieved easily by FPGA-based controllers. On the other hand, the well-known MT method for velocity estimation has been well proven in practice. However, its complexity, which is related to the inherent arithmetic division involved in the calculus part of the method, prevents its holistic implementation as a single-chip solution on small-size low-cost FPGAs that are suitable for practical optimized control systems. In order to overcome this obstacle, we proposed a division-less MT-type algorithm that consumes only minimal FPGA resources, which makes it proper for modern cost-optimized FPGAs. In this paper, we present new results. The recursive discrete algorithm has been further optimized, in order to improve the accuracy of the velocity estimation. The novel algorithm has also been implemented on the experimental FPGA board, and validated by practical experiments. The enhanced algorithm design resulted in improved practical performance.
      Citation: Electronics
      PubDate: 2019-03-25
      DOI: 10.3390/electronics8030361
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 362: LLC Resonant Converter for LEV (Light
           Electric Vehicle) Fast Chargers

    • Authors: Do-Hyun Kim, Min-Soo Kim, Sarvar Hussain Nengroo, Chang-Hee Kim, Hee-Je Kim
      First page: 362
      Abstract: This paper presents a Light Electric Vehicle (LEV) fast charger with a Lithium-Ion Battery (LIB) and Super-Capacitor (SC). The LEV fast charger consists of an AC/DC rectifier and LLC (Inductor-Inductor-Capacitor) resonant Full bridge converter. The LLC resonant converter has high-efficiency and low switching loss because of Zero Voltage Switching (ZVS). So, it is used widely in the industry. In general, the fast charger algorithm uses the Constant Current (CC) mode and Constant Voltage (CV). The CC mode starts at first and then the CV mode finishes. However, there is a big control value gap between the CC mode and CV mode. Therefore, when changing from CC to CV, the transient state occurs. To compensate for the transient state, we propose a new control algorithm. By means of this algorithm, we can achieve a higher level of safety and stability. The fast charger with LIB of 800 Wh and SC of 50 Wh is analyzed and verified, and we obtain a maximum efficiency of 96.4%. The discussions are validated using the LLC resonant full bridge converter prototype at the laboratory level.
      Citation: Electronics
      PubDate: 2019-03-25
      DOI: 10.3390/electronics8030362
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 363: Modeling and Control of the Starter Motor
           and Start-Up Phase for Gas Turbines

    • Authors: Soheil Jafari, Seyed Alireza Miran Fashandi, Theoklis Nikolaidis
      First page: 363
      Abstract: Improving the performance of industrial gas turbines has always been at the focus of attention of researchers and manufacturers. Nowadays, the operating environment of gas turbines has been transformed significantly respect to the very fast growth of renewable electricity generation where gas turbines should provide a safe, reliable, fast, and flexible transient operation to support their renewable partners. So, having a reliable tools to predict the transient behavior of the gas turbine is becoming more and more important. Regarding the response time and flexibility, improving the turbine performance during the start-up phase is an important issue that should be taken into account by the turbine manufacturers. To analyze the turbine performance during the start-up phase and to implement novel ideas so as to improve its performance, modeling, and simulation of an industrial gas turbine during cold start-up phase is investigated this article using an integrated modular approach. During this phase, a complex mechatronic system comprised of an asynchronous AC motor (electric starter), static frequency converter drive, and gas turbine exists. The start-up phase happens in this manner: first, the clutch transfers the torque generated by the electric starter to the gas turbine so that the turbine reaches a specific speed (cranking stage). Next, the turbine spends some time at this speed (purging stage), after which the turbine speed decreases, sparking stage begins, and the turbine enters the warm start-up phase. It is, however, possible that the start-up process fails at an intermediate stage. Such unsuccessful start-ups can be caused by turbine vibrations, the increase in the gradients of exhaust gases, or issues with fuel spray nozzles. If, for any reason, the turbine cannot reach the self-sustained speed and the speed falls below a certain threshold, the clutch engages once again with the turbine shaft and the start-up process is repeated. Consequently, when modeling the start-up phase, we face discontinuities in performance and a system with variable structure owing to the existence of clutch. Modeling the start-up phase, which happens to exist in many different fields including electric and mechanical application, brings about problems in numerical solutions (such as algebraic loop). Accordingly, this study attempts to benefit from the bond graph approach (as a powerful physical modeling approach) to model such a mechatronic system. The results confirm the effectiveness of the proposed approach in detailed performance prediction of the gas turbine in start-up phase.
      Citation: Electronics
      PubDate: 2019-03-25
      DOI: 10.3390/electronics8030363
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 364: A Topology-Based Approach to Improve
           Vehicle-Level Electromagnetic Radiation

    • Authors: Cunxue Wu, Feng Gao, Hanzhe Dai, Zilong Wang
      First page: 364
      Abstract: The popularity of the electric vehicle (EV) brings us many challenges of electromagnetic compatibility (EMC). Automotive manufacturers are obliged to keep their products in compliance with EMC regulations. However, the EV is a complex system composed of various electromagnetic interferences (EMI), sensitive equipment and complicated coupling paths, which pose great challenges to the efficient troubleshooting of EMC problems. This paper presents an electromagnetic topology (EMT) based model and analysis method for vehicle-level EMI prediction, which decomposes an EV into multi-subsystems and transforms electromagnetic coupling paths into network parameters. This way, each part could be modelled separately with different technologies and vehicle-level EMI was able to be predicted by algebra calculations. The effectiveness of the proposed method was validated by comparing predicted vehicle-radiated emissions at low frequency with experimental results, and application to the troubleshooting of emission problems.
      Citation: Electronics
      PubDate: 2019-03-25
      DOI: 10.3390/electronics8030364
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 365: Analysis and Experimental Test of
           Electrical Characteristics on Bonding Wire

    • Authors: Wenchao Tian, Hao Cui, Wenbo Yu
      First page: 365
      Abstract: In this paper, electrical characteristic analysis and corresponding experimental tests on gold bonding wire are presented. Firstly, according to EIA (Electronic Industries Association)/JEDEC97 standards, this paper establishes the electromagnetic structure model of gold bonding wire. The parameters, including flat length ratio, diameter, span and bonding height, were analyzed. In addition, the influence of three kinds of loops of bonding wire is discussed in relation to the S parameters. An equivalent circuit model of bonding wire is proposed. The effect of bonding wire on signal transmission was analyzed by eye diagram as well. Secondly, gold bonding wire design and measurement experiments were implemented based on radio frequency (RF) circuit theory analysis and test methods. Meanwhile, the original measurement data was compared with the simulation model data and the error was analyzed. At last, the data of five frequency points were processed to eliminate the fixture error as much as possible based on port embedding theory. The measurement results using port extension method were compared with the original measurement data and electromagnetic field simulation data, which proved the correctness of the simulation results and design rules.
      Citation: Electronics
      PubDate: 2019-03-26
      DOI: 10.3390/electronics8030365
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 366: Magnetic Switching of a Stoner-Wohlfarth
           Particle Subjected to a Perpendicular Bias Field

    • Authors: Dong Xue, Weiguang Ma
      First page: 366
      Abstract: Characterized by uniaxial magnetic anisotropy, the Stoner-Wohlfarth particle experiences a change in magnetization leading to a switch in behavior when tuned by an externally applied field, which relates to the perpendicular bias component (hperp) that remains substantially small in comparison with the constant switching field (h0). The dynamics of the magnetic moment that governs the magnetic switching is studied numerically by solving the Landau-Lifshitz-Gilbert (LLG) equation using the Mathematica code without any physical approximations; the results are compared with the switching time obtained from the analytic method that intricately treats the non-trivial bias field as a perturbation. A good agreement regarding the magnetic switching time (ts) between the numerical calculation and the analytic results is found over a wide initial angle range (0.01 < θ0 < 0.3), as h0 and hperp are 1.5 × K and 0.02 × K, where K represents the anisotropy constant. However, the quality of the analytic approximation starts to deteriorate slightly in contrast to the numerical approach when computing ts in terms of the field that satisfies hperp > 0.15 × K and h0 = 1.5 × K. Additionally, existence of a comparably small perpendicular bias field (hperp << h0) causes ts to decrease in a roughly exponential manner when hperp increases.
      Citation: Electronics
      PubDate: 2019-03-26
      DOI: 10.3390/electronics8030366
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 367: Open-Source Hardware Platforms for Smart
           Converters with Cloud Connectivity

    • Authors: Massimo Merenda, Demetrio Iero, Giovanni Pangallo, Paolo Falduto, Giovanna Adinolfi, Angelo Merola, Giorgio Graditi, Francesco G. Della Corte
      First page: 367
      Abstract: This paper presents the design and hardware implementation of open-source hardware dedicated to smart converter systems development. Smart converters are simple or interleaved converters. They are equipped with controllers that are able to online impedance match for the maximum power transfer. These conversion systems are particularly feasible for photovoltaic and all renewable energies systems working in continuous changing operating conditions. Smart converters represent promising solutions in recent energetic scenarios, in fact their application is deepening and widening. In this context, the availability of a hardware platform could represent a useful tool. The platform was conceived and released as an open hardware instrument for academy and industry to benefit from the improvements brought by the researchers’ community. The usage of a novel, open-source platform would allow many developers to design smart converters, focusing on algorithms instead of electronics, which could result in a better overall development ecosystem and rapid growth in the number of smart converter applications. The platform itself is proposed as a benchmark in the development and testing of different maximum power point tracking algorithms. The designed system is capable of accurate code implementations, allowing the testing of different current and voltage-controlled algorithms for different renewable energies systems. The circuit features a bi-directional radio frequency communication channel that enables real-time reading of measurements and parameters, and remote modification of both algorithm types and settings. The proposed system was developed and successfully tested in laboratory with a solar module simulator and with real photovoltaic generators. Experimental results indicate state-of-art performances as a converter, while enhanced smart features pave the way to system-level management, real-time diagnostics, and on-the-flight parameters change. Furthermore, the deployment feasibility allows different combinations and arrangements of several energy sources, converters (both single and multi-converters), and modulation strategies. To our knowledge, this project remains the only open-source hardware smart converter platform used for educational, research, and industrial purposes so far.
      Citation: Electronics
      PubDate: 2019-03-26
      DOI: 10.3390/electronics8030367
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 368: Design and Development of a Reduced
           Form-Factor High Accuracy Three-Axis Teslameter

    • Authors: Cassar, Sammut, Sammut, Calvi, Dimitrijevic, Popovic
      First page: 368
      Abstract: A novel three-axis teslameter and other similar machines have been designed and developed for SwissFEL at the Paul Scherrer Institute (PSI). The developed instrument will be used for high fidelity characterisation and optimisation of the undulators for the ATHOS soft X-ray beamline. The teslameter incorporates analogue signal conditioning for the three-axes interface to a SENIS Hall probe, an interface to a Heidenhain linear absolute encoder and an on-board high-resolution 24-bit analogue-to-digital conversion. This is in contrast to the old instrumentation setup used, which only comprises the analogue circuitry with digitization being done externally to the instrument. The new instrument fits in a volumetric space of 150 mm × 50 mm × 45 mm, being very compact in size and also compatible with the in-vacuum undulators. This paper describes the design and the development of the different components of the teslameter. Performance results are presented that demonstrate offset fluctuation and drift (0.1–10 Hz) with a standard deviation of 0.78 µT and a broadband noise (10–500 Hz) of 2.05 µT with an acquisition frequency of 2 kHz.
      Citation: Electronics
      PubDate: 2019-03-26
      DOI: 10.3390/electronics8030368
      Issue No: Vol. 8, No. 3 (2019)
       
  • Electronics, Vol. 8, Pages 369: Multi-Objective Service Restoration of
           Radial Distribution System in the Presence of Non-Linear Loads

    • Authors: Ishan Srivastava, Sunil Bhat, Agarala Ajaysekhar Reddy
      First page: 369
      Abstract: Most of the power electronic components act as non-linear loads because they draw non- sinusoidal current from the power supply. Due to these non-linear loads, current harmonics are injected in the power network. For normal operation, any power network is equipped with provisions to keep the harmonics level to a minimum value. Whenever a fault occurs in the distribution system, the primary goal is to re-energize the healthy part of the network which got interrupted. It can be done by changing the topology of the network. This method is called as Service Restoration (SR). In this paper, a service restoration strategy is proposed when non-linear loads are present in the radial distribution system. Service restoration problem is formulated as a multi-objective, constrained optimization problem. Three new objectives are included to address the problem of harmonics injection by non-linear loads. Multi-Objective Particle Swarm Optimization (MOPSO) and Non-Dominated Sorting Genetic Algorithm-II (NSGA-II) are used to find the optimal switching sequence for restoration. To test the effectiveness of the proposed methodology, IEEE 33 bus and IEEE 69 bus test systems are taken.
      Citation: Electronics
      PubDate: 2019-03-26
      DOI: 10.3390/electronics8030369
      Issue No: Vol. 8, No. 3 (2019)
       
 
 
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