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Electronics
Volume 11
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Electronics, Volume 11, Issue 2 (January-2 2022) – 121 articles

Cover Story (view full-size image): The novelty described in this paper is a formal description of a vineyard configuration (layout) extended by a set of parameters related to individual vineyard elements and the vineyard as a whole. We also present a method for estimating the energy consumption of the robotic system based on this formal description and on input data collected before the pure deployment of the described robotic system. The main advantage of our approach is that it allows the end user to estimate the duration and energy requirements for using the robot in the desired vineyard before visiting the vineyard. In addition, the design of the hardware for use in steep vineyards and two experiments in which the proposed methodology was demonstrated are presented. View this paper
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37 pages, 1996 KiB  
Review
A Systematic Review on Oral Interactions in Robot-Assisted Language Learning
by Vivien Lin, Hui-Chin Yeh and Nian-Shing Chen
Electronics 2022, 11(2), 290; https://doi.org/10.3390/electronics11020290 - 17 Jan 2022
Cited by 19 | Viewed by 3851
Abstract
Although educational robots are known for their capability to support language learning, how actual interaction processes lead to positive learning outcomes has not been sufficiently examined. To explore the instructional design and the interaction effects of robot-assisted language learning (RALL) on learner performance, [...] Read more.
Although educational robots are known for their capability to support language learning, how actual interaction processes lead to positive learning outcomes has not been sufficiently examined. To explore the instructional design and the interaction effects of robot-assisted language learning (RALL) on learner performance, this study systematically reviewed twenty-two empirical studies published between 2010 and 2020. Through an inclusion/exclusion procedure, general research characteristics such as the context, target language, and research design were identified. Further analysis on oral interaction design, including language teaching methods, interactive learning tasks, interaction processes, interactive agents, and interaction effects showed that the communicative or storytelling approach served as the dominant methods complemented by total physical response and audiolingual methods in RALL oral interactions. The review provides insights on how educational robots can facilitate oral interactions in language classrooms, as well as how such learning tasks can be designed to effectively utilize robotic affordances to fulfill functions that used to be provided by human teachers alone. Future research directions point to a focus on meaning-based communication and intelligibility in oral production among language learners in RALL. Full article
(This article belongs to the Special Issue Recent Advances in Educational Robotics)
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21 pages, 6770 KiB  
Article
A Novel Localization Algorithm Based on RSSI and Multilateration for Indoor Environments
by Jinze Du, Chao Yuan, Min Yue and Tao Ma
Electronics 2022, 11(2), 289; https://doi.org/10.3390/electronics11020289 - 17 Jan 2022
Cited by 17 | Viewed by 3542
Abstract
Indoor localization algorithms based on the received signal strength indicator (RSSI) in wireless sensor networks (WSNs) have higher localization accuracy than other range-free methods. This paper considers indoor localization based on multilateration and averaged received signal strength indicator (RSSI). We propose an approach [...] Read more.
Indoor localization algorithms based on the received signal strength indicator (RSSI) in wireless sensor networks (WSNs) have higher localization accuracy than other range-free methods. This paper considers indoor localization based on multilateration and averaged received signal strength indicator (RSSI). We propose an approach called weighted three minimum distances method (WTM) to deal with the poor accuracy of distances deduced from RSSI. Using a practical localization system, an experimental channel model is deduced to assess the performance of the proposed localization algorithm in realistic conditions. Both simulated data and measured data are used to verify the proposed method. Compared with nonlinear least squares (NLS), Levenberg–Marquardt algorithm (LM) and semidefinite programming method (SDP), simulations show that the proposed method exhibits better localization accuracy but consumes more calculation time. Full article
(This article belongs to the Special Issue Challenges and Complexities in Emerging Smart Cities)
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19 pages, 4358 KiB  
Article
A New Method of Dynamic Horizontal Fragmentation for Multimedia Databases Contemplating Content-Based Queries
by Felipe Castro-Medina, Lisbeth Rodríguez-Mazahua, Asdrúbal López-Chau, Jair Cervantes, Giner Alor-Hernández, Isaac Machorro-Cano and Mario Leoncio Arrioja-Rodríguez
Electronics 2022, 11(2), 288; https://doi.org/10.3390/electronics11020288 - 17 Jan 2022
Cited by 3 | Viewed by 1899
Abstract
The proper storage and management of multimedia data is a topic of great interest to industry and academia. Database fragmentation plays a fundamental role as a mechanism to guarantee cost reduction and improve response time performance in distributed data management environments. Multimedia database [...] Read more.
The proper storage and management of multimedia data is a topic of great interest to industry and academia. Database fragmentation plays a fundamental role as a mechanism to guarantee cost reduction and improve response time performance in distributed data management environments. Multimedia database access patterns are constantly changing; due to this, it is important that the partitioning schemes also adapt to these changes. Dynamic fragmentation techniques offer this advantage and represent a reduction of the tasks that an administrator must perform and the complete autonomy to determine when to carry out a new fragmentation based on a cost model. This work proposes a new method of dynamic horizontal fragmentation for multimedia databases, including a way to contemplate content-based queries in the creation of new fragments. The use of content-based queries is on the rise, as multimedia elements are often presented within databases, and for this reason new fragmentation strategies must include this aspect to provide better-performing schemas. The method included in this research is placed within a current web application called XAMANA. We performed some experiments to demonstrate the effectiveness of our approach. Full article
(This article belongs to the Section Computer Science & Engineering)
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25 pages, 3833 KiB  
Article
Power Quality Monitoring Strategy Based on an Optimized Multi-Domain Feature Selection for the Detection and Classification of Disturbances in Wind Generators
by David A. Elvira-Ortiz, Juan J. Saucedo-Dorantes, Roque A. Osornio-Rios, Daniel Morinigo-Sotelo and Jose A. Antonino-Daviu
Electronics 2022, 11(2), 287; https://doi.org/10.3390/electronics11020287 - 17 Jan 2022
Cited by 8 | Viewed by 1896
Abstract
Wind generation has recently become an essential renewable power supply option. Wind generators are integrated with electrical machines that require correct functionality. However, the increasing use of non-linear loads introduces undesired disturbances that may compromise the integrity of the electrical machines inside the [...] Read more.
Wind generation has recently become an essential renewable power supply option. Wind generators are integrated with electrical machines that require correct functionality. However, the increasing use of non-linear loads introduces undesired disturbances that may compromise the integrity of the electrical machines inside the wind generator. Therefore, this work proposes a five-step methodology for power quality disturbance detection in grids with injection of wind farm energy. First, a database with synthetic signals is generated, to be used in the training process. Then, a multi-domain feature estimation is carried out. To reduce the problematic dimensionality, the features that provide redundant information are eliminated through an optimized feature selection performed by means of a genetic algorithm and the principal component analysis. Additionally, each one of the characteristic feature matrices of every considered condition are modeled through a specific self-organizing map neuron grid so they can be shown in a 2-D representation. Since the SOM model provides a pattern of the behavior of every disturbance, they are used as inputs of the classifier, based in a softmax layer neural network that performs the power quality disturbance detection of six different conditions: healthy or normal, sag or swell voltages, transients, voltage fluctuations and harmonic distortion. Thus, the proposed method is validated using a set of synthetic signals and is then tested using two different sets of real signals from an IEEE workgroup and from a wind park located in Spain. Full article
(This article belongs to the Special Issue Robust Design Optimization of Electrical Machines and Devices)
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14 pages, 4125 KiB  
Article
New Resistor-Less Electronically Controllable ±C Simulator Employing VCII, DVCC, and a Grounded Capacitor
by Giuseppe Ferri, Leila Safari, Gianluca Barile, Massimo Scarsella and Vincenzo Stornelli
Electronics 2022, 11(2), 286; https://doi.org/10.3390/electronics11020286 - 17 Jan 2022
Cited by 17 | Viewed by 1425
Abstract
In this paper, a new realization of electronically controllable positive and negative floating capacitor multiplier (±C) is presented. The peculiarity of the presented topology is that, for the first time, it implements a floating equivalent capacitor between its two input terminals, rather than [...] Read more.
In this paper, a new realization of electronically controllable positive and negative floating capacitor multiplier (±C) is presented. The peculiarity of the presented topology is that, for the first time, it implements a floating equivalent capacitor between its two input terminals, rather than a grounded one. To achieve the best performance, we simultaneously use the advantages provided by the current conveyor and its dual circuit, the voltage conveyor. The proposed topology is resistor free and employs one dual-output second-generation voltage conveyor (VCII±) and one electronically tunable differential voltage current conveyor (E-DVCC) as active building blocks (ABBs) and a single grounded capacitor. The value of the simulated capacitor is controlled by means of a control voltage VC which is used to control the current gain between X and Z terminals of E-DVCC. The circuit is free from any matching condition. A complete non-ideal analysis by considering parasitic impedances as well as non-ideal current and voltage gains of the used ABBs is presented. The proposed circuit is designed at the transistor level in 0.18 µm and ±0.9 V supply voltage. Simulation results using the SPICE program show a multiplication factor ranging from ±10 to ±25.4 with a maximum error of 0.56%. As an example, the application of the achieved floating capacitor as a standard high pass filter is also included. Full article
(This article belongs to the Section Circuit and Signal Processing)
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21 pages, 6206 KiB  
Article
A Hybrid Driver Fatigue and Distraction Detection Model Using AlexNet Based on Facial Features
by Salma Anber, Wafaa Alsaggaf and Wafaa Shalash
Electronics 2022, 11(2), 285; https://doi.org/10.3390/electronics11020285 - 17 Jan 2022
Cited by 11 | Viewed by 3314
Abstract
Modern cities have imposed a fast-paced lifestyle where more drivers on the road suffer from fatigue and sleep deprivation. Consequently, road accidents have increased, becoming one of the leading causes of injuries and death among young adults and children. These accidents can be [...] Read more.
Modern cities have imposed a fast-paced lifestyle where more drivers on the road suffer from fatigue and sleep deprivation. Consequently, road accidents have increased, becoming one of the leading causes of injuries and death among young adults and children. These accidents can be prevented if fatigue symptoms are diagnosed and detected sufficiently early. For this reason, we propose and compare two AlexNet CNN-based models to detect drivers’ fatigue behaviors, relying on head position and mouth movements as behavioral measures. We used two different approaches. The first approach is transfer learning, specifically, fine-tuning AlexNet, which allowed us to take advantage of what the model had already learned without developing it from scratch. The newly trained model was able to predict drivers’ drowsiness behaviors. The second approach is the use of AlexNet to extract features by training the top layers of the network. These features were reduced using non-negative matrix factorization (NMF) and classified with a support vector machine (SVM) classifier. The experiments showed that our proposed transfer learning model achieved an accuracy of 95.7%, while the feature extraction SVM-based model performed better, with an accuracy of 99.65%. Both models were trained on a simulated NTHU Driver Drowsiness Detection dataset. Full article
(This article belongs to the Topic Machine and Deep Learning)
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16 pages, 3396 KiB  
Article
Enhancement of the Evaporation and Condensation Processes of a Solar Still with an Ultrasound Cotton Tent and a Thermoelectric Cooling Chamber
by Naseer T. Alwan, Ayad S. Ahmed, Milia H. Majeed, Sergey E. Shcheklein, Salam J. Yaqoob, Anand Nayyar, Yunyoung Nam and Mohamed Abouhawwash
Electronics 2022, 11(2), 284; https://doi.org/10.3390/electronics11020284 - 17 Jan 2022
Cited by 6 | Viewed by 2086
Abstract
In this paper, an experimental investigation study was conducted to show the effect of enhancing the evaporation and condensation processes inside a modified solar still by placing ultrasonic humidifiers inside a cotton mesh tent in the basin water and by installing a cooling [...] Read more.
In this paper, an experimental investigation study was conducted to show the effect of enhancing the evaporation and condensation processes inside a modified solar still by placing ultrasonic humidifiers inside a cotton mesh tent in the basin water and by installing a cooling chamber with thermoelectric elements on top of the solar still. Various parameters were recorded every hour, such as temperatures at different points within the solar still, the weather conditions (e.g., solar irradiance intensity, ambient air temperature, and wind speed), the yield of distilled water, and thermal efficiency on 29 July 2021 at the Ural Federal University (Russia). The production cost of distilled water from modified and traditional solar stills was also estimated. The experimental results showed that the productivity of the modified solar still increased by 124% compared with the traditional solar still, and the highest thermal efficiency was recorded at 2:00 p.m. (approximately 95.8% and 35.6% for modified and traditional solar stills, respectively). Finally, the productivity cost of distillate water (1 L) was approximately 0.040 and 0.042 $/L for the modified and traditional solar stills, respectively. The current work has contributed to increasing solar still productivity by applying simple and new technologies with the lowest possible capital and operational costs. Full article
(This article belongs to the Topic Advanced Systems Engineering: Theory and Applications)
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16 pages, 1649 KiB  
Article
Fog-Computing-Based Cyber–Physical System for Secure Food Traceability through the Twofish Algorithm
by Kamran Ahmad Awan, Ikram Ud Din, Ahmad Almogren and Byung-Seo Kim
Electronics 2022, 11(2), 283; https://doi.org/10.3390/electronics11020283 - 17 Jan 2022
Cited by 2 | Viewed by 1552
Abstract
The Internet is an essential part of daily life with the expansion of businesses for maximizing profits. This technology has intensely altered the traditional shopping style in online shopping. Convenience, quick price comparison, saving traveling time, and avoiding crowds are the reasons behind [...] Read more.
The Internet is an essential part of daily life with the expansion of businesses for maximizing profits. This technology has intensely altered the traditional shopping style in online shopping. Convenience, quick price comparison, saving traveling time, and avoiding crowds are the reasons behind the abrupt adoption of online shopping. However, in many situations, the product provided does not meet the quality, which is the primary concern of every customer. To ensure quality product provision, the whole food supply chain should be examined and managed properly. In food traceability systems, sensors are used to gather product information, which is forwarded to fog computing. However, the product information forwarded by the sensors may not be similar, as it can be modified by intruders/hackers. Moreover, consumers are interested in the product location, as well as its status, i.e., manufacturing date, expiry date, etc. Therefore, in this paper, data and account security techniques were introduced to efficiently secure product information through the Twofish algorithm and dual attestation for account verification. To improve the overall working, the proposed mechanism integrates fog computing with novel modules to efficiently monitor the product, along with increasing the efficiency of the whole working process. To validate the performance of the proposed system, a comparative simulation was performed with existing approaches in which Twofish showed notably better results in terms of encryption time, computational cost, and the identification of modification attacks. Full article
(This article belongs to the Special Issue Novel Cloud-Based Service/Application Platforms and Ecosystems)
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20 pages, 5734 KiB  
Article
A Novel Power-Saving Reversing Camera System with Artificial Intelligence Object Detection
by Kuo-Ching Hung, Meng-Chun Lin and Sheng-Fuu Lin
Electronics 2022, 11(2), 282; https://doi.org/10.3390/electronics11020282 - 17 Jan 2022
Viewed by 1901
Abstract
According to a study by the Insurance Institute for Highway Safety (IIHS), the driving collision rate of using only the reversing camera system is lower than that of using both the reversing camera system and the reversing radar. In this article, we implemented [...] Read more.
According to a study by the Insurance Institute for Highway Safety (IIHS), the driving collision rate of using only the reversing camera system is lower than that of using both the reversing camera system and the reversing radar. In this article, we implemented a reversing camera system with artificial intelligence object detection to increase the information of the reversing image. Our system consists of an image processing chip (IPC) with wide-angle image distortion correction and an image buffer controller, a low-power KL520 chip and an optimized artificial intelligence model MobileNetV2-YOLOV3-Optimized (MNYLO). The results of the experiment show the three advantages of our system. Firstly, through the image distortion correction of IPC, we can restore the distorted reversing image. Secondly, by using a public dataset and collected images of various weathers for artificial intelligence model training, our system does not need to use image algorithms that eliminate bad weathers such as rain, fog, and snow to restore polluted images. Objects can still be detected by our system in images contaminated by weather. Thirdly, compared with the AI model Tiny_YOLOV3, not only the parameters of our MNYLO have been reduced by 72.3%, the amount of calculation has been reduced by 86.4%, but the object detection rate has also been maintained and avoided sharp drops. Full article
(This article belongs to the Section Artificial Intelligence Circuits and Systems (AICAS))
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11 pages, 1040 KiB  
Article
Investigation on High-Efficiency Beam-Wave Interaction for Coaxial Multi-Beam Relativistic Klystron Amplifier
by Limin Sun, Hua Huang, Shifeng Li, Zhengbang Liu, Hu He, Qifan Xiang, Ke He and Xianghe Fang
Electronics 2022, 11(2), 281; https://doi.org/10.3390/electronics11020281 - 17 Jan 2022
Cited by 6 | Viewed by 2319
Abstract
To significantly improve the electronic efficiency of coaxial multi-beam relativistic klystron amplifier (CMB-RKA), the physical process of beam-wave interaction and parameters that affect efficiency was studied. First, the high efficiency of beam-wave interaction was discussed by simulating the efficiency versus the parameters (frequency [...] Read more.
To significantly improve the electronic efficiency of coaxial multi-beam relativistic klystron amplifier (CMB-RKA), the physical process of beam-wave interaction and parameters that affect efficiency was studied. First, the high efficiency of beam-wave interaction was discussed by simulating the efficiency versus the parameters (frequency of cavity, drift tube length between cavities, and external quality factor of output cavity), in the one-dimensional (1-D) large-signal simulation software. Moreover, the further physical process of beam-wave interaction was analyzed through simulating the current modulation factor and the number of particles at the entrance of the output cavity, in the three-dimensional (3-D) particle in cell simulation software. Last, with the optimal parameters in 3-D simulations, the CMB-RKA, which has 14 electron beams with a total current of 4.2 kA (14 × 300 A), can generate an output power of 1.02 GW with a saturation gain of 55.6 dB and an efficiency of 48.7%, when beam voltage is 500 kV, which indicated the CMB-RKA can achieve high efficiency for high-power microwave radiation. Full article
(This article belongs to the Special Issue High-Frequency Vacuum Electron Devices)
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49 pages, 24241 KiB  
Article
Novel Motor-Kinetic-Energy-Based Power Pulsation Buffer Concept for Single-Phase-Input Electrolytic-Capacitor-Less Motor-Integrated Inverter System
by Michael Haider, Dominik Bortis, Grayson Zulauf, Johann W. Kolar and Yasuo Ono
Electronics 2022, 11(2), 280; https://doi.org/10.3390/electronics11020280 - 16 Jan 2022
Cited by 3 | Viewed by 3534
Abstract
The motor integration of singe-phase-supplied Variable-Speed Drives (VSDs) is prevented by the significant volume, short lifetime, and operating temperature limit of the electrolytic capacitors required to buffer the pulsating power grid. The DC-link energy storage requirement is eliminated by using the kinetic energy [...] Read more.
The motor integration of singe-phase-supplied Variable-Speed Drives (VSDs) is prevented by the significant volume, short lifetime, and operating temperature limit of the electrolytic capacitors required to buffer the pulsating power grid. The DC-link energy storage requirement is eliminated by using the kinetic energy of the motor as a buffer. The proposed concept is called the Motor-Integrated Power Pulsation Buffer (MPPB), and a control technique and structure are detailed that meet the requirements for nominal and faulted operation with a simple reconfiguration of existing controller blocks. A 7.5 KW, motor-integrated hardware demonstrator validated the proposed MPPB concept and loss models for a scroll compressor drive used in auxiliary railway applications. The MPPB drive with a front-end CISPR 11/Class A EMI filter, PFC rectifier stage, and output-side inverter stage achieved a power density of 0.91 KW L−1 (15 W in−3). The grid-to-motor-shaft efficiency exceeded 90% for all loads over 5 kW or 66% of nominal load, with a worst-case loss penalty over a conventional system of only 17%. Full article
(This article belongs to the Special Issue 10th Anniversary of Electronics: Recent Advances in Power Electronics)
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20 pages, 1517 KiB  
Article
C-V2X Centralized Resource Allocation with Spectrum Re-Partitioning in Highway Scenario
by Saif Sabeeh, Krzysztof Wesołowski and Paweł Sroka
Electronics 2022, 11(2), 279; https://doi.org/10.3390/electronics11020279 - 16 Jan 2022
Cited by 10 | Viewed by 2149
Abstract
Cellular Vehicle-to-Everything communication is an important scenario of 5G technologies. Modes 3 and 4 of the wireless systems introduced in Release 14 of 3GPP standards are intended to support vehicular communication with and without cellular infrastructure. In the case of Mode 3, dynamic [...] Read more.
Cellular Vehicle-to-Everything communication is an important scenario of 5G technologies. Modes 3 and 4 of the wireless systems introduced in Release 14 of 3GPP standards are intended to support vehicular communication with and without cellular infrastructure. In the case of Mode 3, dynamic resource selection and semi-persistent resource scheduling algorithms result in a signalling cost problem between vehicles and infrastructure, therefore, we propose a means to decrease it. This paper employs Re-selection Counter in centralized resource allocation as a decremental counter of new resource requests. Furthermore, two new spectrum re-partitioning and frequency reuse techniques in Roadside Units (RSUs) are considered to avoid resource collisions and diminish high interference impact via increasing the frequency reuse distance. The two techniques, full and partial frequency reuse, partition the bandwidth into two sub-bands. Two adjacent RSUs apply these sub-bands with the Full Frequency Reuse (FFR) technique. In the Partial Frequency Reuse (PFR) technique, the sub-bands are further re-partitioned among vehicles located in the central and edge parts of the RSU coverage. The sub-bands assignment in the nearest RSUs using the same sub-bands is inverted concerning the current RSU to increase the frequency reuse distance. The PFR technique shows promising results compared with the FFR technique. Both techniques are compared with the single band system for different vehicle densities. Full article
(This article belongs to the Special Issue Problems and Challenges of Physical Layer in 5G Systems)
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18 pages, 3740 KiB  
Article
Multi-Scale Memetic Image Registration
by Cătălina Lucia Cocianu and Cristian Răzvan Uscatu
Electronics 2022, 11(2), 278; https://doi.org/10.3390/electronics11020278 - 16 Jan 2022
Cited by 5 | Viewed by 1504
Abstract
Many technological applications of our time rely on images captured by multiple cameras. Such applications include the detection and recognition of objects in captured images, the tracking of objects and analysis of their motion, and the detection of changes in appearance. The alignment [...] Read more.
Many technological applications of our time rely on images captured by multiple cameras. Such applications include the detection and recognition of objects in captured images, the tracking of objects and analysis of their motion, and the detection of changes in appearance. The alignment of images captured at different times and/or from different angles is a key processing step in these applications. One of the most challenging tasks is to develop fast algorithms to accurately align images perturbed by various types of transformations. The paper reports a new method used to register images in the case of geometric perturbations that include rotations, translations, and non-uniform scaling. The input images can be monochrome or colored, and they are preprocessed by a noise-insensitive edge detector to obtain binarized versions. Isotropic scaling transformations are used to compute multi-scale representations of the binarized inputs. The algorithm is of memetic type and exploits the fact that the computation carried out in reduced representations usually produces promising initial solutions very fast. The proposed method combines bio-inspired and evolutionary computation techniques with clustered search and implements a procedure specially tailored to address the premature convergence issue in various scaled representations. A long series of tests on perturbed images were performed, evidencing the efficiency of our memetic multi-scale approach. In addition, a comparative analysis has proved that the proposed algorithm outperforms some well-known registration procedures both in terms of accuracy and runtime. Full article
(This article belongs to the Special Issue Computer Vision Techniques: Theory and Applications)
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11 pages, 1985 KiB  
Article
The Structural and Dielectric Properties of Bi3−xNdxTi1.5W0.5O9 (x = 0.25, 0.5, 0.75, 1.0)
by Sergei V. Zubkov, Ivan A. Parinov and Yulia A. Kuprina
Electronics 2022, 11(2), 277; https://doi.org/10.3390/electronics11020277 - 16 Jan 2022
Cited by 2 | Viewed by 1400
Abstract
A new series of layered perovskite-like oxides Bi3−xNdxTi1.5W0.5O9 (x = 0.25, 0.5, 0.75, 1.0) was synthesized by the method of high-temperature solid-state reaction, in which partial substitution of bismuth (Bi) atoms in the dodecahedra [...] Read more.
A new series of layered perovskite-like oxides Bi3−xNdxTi1.5W0.5O9 (x = 0.25, 0.5, 0.75, 1.0) was synthesized by the method of high-temperature solid-state reaction, in which partial substitution of bismuth (Bi) atoms in the dodecahedra of the perovskite layer (A-positions) by Nd atoms takes place. X-ray structural studies have shown that all compounds are single-phase and have the structure of Aurivillius phases (APs), with close parameters of orthorhombic unit cells corresponding to space group A21am. The dependences of the relative permittivity ε/ε0 and the tangent of loss tgσ at different frequencies on temperature were measured. The piezoelectric constant d33 was measured for Bi3−xNdxTi1.5W0.5O9 (x = 0.25, 0.5, 0.75) compounds of the synthesized series. Full article
(This article belongs to the Special Issue Robust Design Optimization of Electrical Machines and Devices)
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25 pages, 1914 KiB  
Article
Impact of Molecular Electrostatics on Field-Coupled Nanocomputing and Quantum-Dot Cellular Automata Circuits
by Yuri Ardesi, Giuliana Beretta, Marco Vacca, Gianluca Piccinini and Mariagrazia Graziano
Electronics 2022, 11(2), 276; https://doi.org/10.3390/electronics11020276 - 16 Jan 2022
Cited by 5 | Viewed by 2141
Abstract
The molecular Field-Coupled Nanocomputing (FCN) is a promising implementation of the Quantum-dot Cellular Automata (QCA) paradigm for future low-power digital electronics. However, most of the literature assumes all the QCA devices as possible molecular FCN devices, ignoring the molecular physics. Indeed, the electrostatic [...] Read more.
The molecular Field-Coupled Nanocomputing (FCN) is a promising implementation of the Quantum-dot Cellular Automata (QCA) paradigm for future low-power digital electronics. However, most of the literature assumes all the QCA devices as possible molecular FCN devices, ignoring the molecular physics. Indeed, the electrostatic molecular characteristics play a relevant role in the interaction and consequently influence the functioning of the circuits. In this work, by considering three reference molecular species, namely neutral, oxidized, and zwitterionic, we analyze the fundamental devices, aiming to clarify how molecule physics impacts architectural behavior. We thus examine through energy analysis the fundamental cell-to-cell interactions involved in the layouts. Additionally, we simulate a set of circuits using two available simulators: SCERPA and QCADesigner. In fact, ignoring the molecular characteristics and assuming the molecules copying the QCA behavior lead to controversial molecular circuit proposals. This work demonstrates the importance of considering the molecular type during the design process, thus declaring the simulators working scope and facilitating the assessment of molecular FCN as a possible candidate for future digital electronics. Full article
(This article belongs to the Special Issue Modeling and Design of Integrated CMOS Circuit)
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18 pages, 4806 KiB  
Article
Semantic Conceptual Framework for Environmental Monitoring and Surveillance—A Case Study on Forest Fire Video Monitoring and Surveillance
by Ljiljana Šerić, Antonia Ivanda, Marin Bugarić and Maja Braović
Electronics 2022, 11(2), 275; https://doi.org/10.3390/electronics11020275 - 16 Jan 2022
Cited by 9 | Viewed by 1819
Abstract
This paper presents a semantic conceptual framework and definition of environmental monitoring and surveillance and demonstrates an ontology implementation of the framework. This framework is defined in a mathematical formulation and is built upon and focused on the notation of observation systems. This [...] Read more.
This paper presents a semantic conceptual framework and definition of environmental monitoring and surveillance and demonstrates an ontology implementation of the framework. This framework is defined in a mathematical formulation and is built upon and focused on the notation of observation systems. This formulation is utilized in the analysis of the observation system. Three taxonomies are presented, namely, the taxonomy of (1) the sampling method, (2) the value format and (3) the functionality. The definition of concepts and their relationships in the conceptual framework clarifies the task of querying for information related to the state of the environment or conditions related to specific events. This framework aims to make the observation system more queryable and therefore more interactive for users or other systems. Using the proposed semantic conceptual framework, we derive definitions of the distinguished tasks of monitoring and surveillance. Monitoring is focused on the continuous assessment of an environment state and surveillance is focused on the collection of all data relevant for specific events. The proposed mathematical formulation is implemented in the format of the computer readable ontology. The presented ontology provides a general framework for the semantic retrieval of relevant environmental information. For the implementation of the proposed framework, we present a description of the Intelligent Forest Fire Video Monitoring and Surveillance system in Croatia. We present the implementation of the tasks of monitoring and surveillance in the application domain of forest fire management. Full article
(This article belongs to the Special Issue Semantic Technologies for the Protection and Monitoring of Natural and Artificial Environments)
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18 pages, 3959 KiB  
Article
Research on Design and Monitoring of a Development Index of an Industrial Internet Platform Based on a Fixed-Base Index Method
by Keqin Dou, Jun Li and Yong Zhou
Electronics 2022, 11(2), 274; https://doi.org/10.3390/electronics11020274 - 16 Jan 2022
Cited by 3 | Viewed by 4225
Abstract
Accelerating the innovation and development of the Industrial Internet Platform is inevitably necessary for the integration of new-generation information technology and the manufacturing industry. It is also the key point for promoting the construction of manufacturing power and network power. In this paper, [...] Read more.
Accelerating the innovation and development of the Industrial Internet Platform is inevitably necessary for the integration of new-generation information technology and the manufacturing industry. It is also the key point for promoting the construction of manufacturing power and network power. In this paper, based on the comprehensive analysis of the relevant problems of China’s Industrial Internet Platform development monitoring, the development index of the Industrial Internet Platform is designed. Taking a typical domestic Industrial Internet Platform as an example, the development index of the Industrial Internet Platform in 2018, 2019, and 2020 are comprehensively calculated in this paper. The results show that China’s Industrial Internet Platform is rapidly growing in many aspects, such as industrial equipment cloud and industrial APP. There is a large space for improving the industrial knowledge accumulation reuse and the application promotion of small/medium-sized enterprises. The results in this paper can provide scientific suggestions and practical references for the government, enterprises, scientific research institutions, which is of great significance in promoting the healthiness and sustainability of the Industrial Internet Platform. Full article
(This article belongs to the Special Issue Application of Advanced Control Technologies Using Digital Signal Processors)
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17 pages, 1742 KiB  
Article
AMROFloor: An Efficient Aging Mitigation and Resource Optimization Floorplanner for Virtual Coarse-Grained Runtime Reconfigurable FPGAs
by Zeyu Li, Zhao Huang, Quan Wang and Junjie Wang
Electronics 2022, 11(2), 273; https://doi.org/10.3390/electronics11020273 - 15 Jan 2022
Cited by 1 | Viewed by 1327
Abstract
With the rapid reduction of CMOS process size, the FPGAs with high-silicon accumulation technology are becoming more sensitive to aging effects. This reduces the reliability and service life of the device. The offline aging-aware layout planning based on balance stress is an effective [...] Read more.
With the rapid reduction of CMOS process size, the FPGAs with high-silicon accumulation technology are becoming more sensitive to aging effects. This reduces the reliability and service life of the device. The offline aging-aware layout planning based on balance stress is an effective solution. However, the existing methods need to take a long time to solve the floorplanner, and the corresponding layout solutions occupy many on-chip resources. To this end, we proposed an efficient Aging Mitigation and Resource Optimization Floorplanner (AMROFloor) for FPGAs. First, the layout solution is implemented on the Virtual Coarse-Grained Runtime Reconfigurable Architecture, which contributes to avoiding rule constraints for placement and routing. Second, the Maximize Reconfigurable Regions Algorithm (MRRA) is proposed to quickly determine the RRs’ number and size to save the solving time and ensure an effective solution. Furthermore, the Resource Combination Algorithm (RCA) is proposed to optimize the on-chip resources, reducing the on-Chip Resource Utilization (CRU) while achieving the same aging relief effect. Experiments were simulated and implemented on Xilinx FPGA. The results demonstrate that the AMROFloor method designed in this paper can extend the Mean Time to Failure (MTTF) by 13.8% and optimize the resource overhead by 19.2% on average compared to the existing aging-aware layout solutions. Full article
(This article belongs to the Special Issue Real-Time Control of Embedded Systems)
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13 pages, 645 KiB  
Article
Strengthening Quality of Chaotic Bit Sequences
by Michal Melosik and Wieslaw Marszalek
Electronics 2022, 11(2), 272; https://doi.org/10.3390/electronics11020272 - 15 Jan 2022
Cited by 2 | Viewed by 1476
Abstract
We discuss chaos and its quality as measured through the 0-1 test for chaos. When the 0-1 test indicates deteriorating quality of chaos, because of the finite precision representations of real numbers in digital implementations, then the process may eventually lead to a [...] Read more.
We discuss chaos and its quality as measured through the 0-1 test for chaos. When the 0-1 test indicates deteriorating quality of chaos, because of the finite precision representations of real numbers in digital implementations, then the process may eventually lead to a periodic sequence. A simple method for improving the quality of a chaotic signal is to mix the signal with another signal by using the XOR operation. In this paper, such mixing of weak chaotic signals is considered, yielding new signals with improved quality (with K values from the 0-1 test close to 1). In some sense, such a mixing of signals could be considered as a two-layer prevention strategy to maintain chaos. That fact may be important in those applications when the hardware resources are limited. The 0-1 test is used to show the improved chaotic behavior in the case when a continuous signal (for example, from the Chua, Rössler or Lorenz system) intermingles with a discrete signal (for example, from the logistic, Tinkerbell or Henon map). The analysis is presented for chaotic bit sequences. Our approach can further lead to hardware applications, and possibly, to improvements in the design of chaotic bit generators. Several illustrative examples are included. Full article
(This article belongs to the Special Issue Dependability of Emerging Computing Paradigms and Technologies in IoT-Oriented Circuits, Architectures and Algorithms)
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8 pages, 2530 KiB  
Article
Easy Fabrication of Performant SWCNT-Si Photodetector
by Daniele Capista, Maurizio Passacantando, Luca Lozzi, Enver Faella, Filippo Giubileo and Antonio Di Bartolomeo
Electronics 2022, 11(2), 271; https://doi.org/10.3390/electronics11020271 - 14 Jan 2022
Cited by 6 | Viewed by 1463
Abstract
We propose a simple method to fabricate a photodetector based on the carbon nanotube/silicon nitride/silicon (CNT/Si3N4/Si) heterojunction. The device is obtained by depositing a freestanding single-wall carbon nanotube (SWCNT) film on a silicon substrate using a dry transfer technique. [...] Read more.
We propose a simple method to fabricate a photodetector based on the carbon nanotube/silicon nitride/silicon (CNT/Si3N4/Si) heterojunction. The device is obtained by depositing a freestanding single-wall carbon nanotube (SWCNT) film on a silicon substrate using a dry transfer technique. The SWCNT/Si3N4/Si heterojunction is formed without the thermal stress of chemical vapor deposition used for the growth of CNTs in other approaches. The CNT film works as a transparent charge collecting electrode and guarantees a uniform photocurrent across the sensitive area of the device. The obtained photodetector shows a great photocurrent that increases linearly with the incident light intensity and grows with the increasing wavelength in the visible range. The external quantum efficiency is independent of the light intensity and increases with the wavelength, reaching 65% at 640 nm. Full article
(This article belongs to the Section Optoelectronics)
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21 pages, 3718 KiB  
Article
Optimal Field Sampling of Arc Sources via Asymptotic Study of the Radiation Operator
by Raffaele Moretta, Giovanni Leone, Fortuna Munno and Rocco Pierri
Electronics 2022, 11(2), 270; https://doi.org/10.3390/electronics11020270 - 14 Jan 2022
Cited by 1 | Viewed by 1169
Abstract
In this paper, the question of how to efficiently sample the field radiated by a circumference arc source is addressed. Classical sampling strategies require the acquisition of a redundant number of field measurements that can make the acquisition time prohibitive. For such reason, [...] Read more.
In this paper, the question of how to efficiently sample the field radiated by a circumference arc source is addressed. Classical sampling strategies require the acquisition of a redundant number of field measurements that can make the acquisition time prohibitive. For such reason, the paper aims at finding the minimum number of basis functions representing the radiated field with good accuracy and at providing an interpolation formula of the radiated field that exploits a non-redundant number of field samples. To achieve the first task, the number of relevant singular values of the radiation operator is computed by exploiting a weighted adjoint operator. In particular, the kernel of the related eigenvalue problem is first evaluated asymptotically; then, a warping transformation and a proper choice of the weight function are employed to recast such a kernel as a convolution and bandlimited function of sinc type. Finally, the number of significant singular values of the radiation operator is found by invoking the Slepian–Pollak results. The second task is achieved by exploiting a Shannon sampling expansion of the reduced field. The analysis is developed for both the far and the near fields radiated by a 2D scalar arc source observed on a circumference arc. Full article
(This article belongs to the Topic Antennas)
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15 pages, 2258 KiB  
Article
On the Performance of Energy Criterion Method in Wi-Fi Transient Signal Detection
by Ismail Mohamed, Yaser Dalveren, Ferhat Ozgur Catak and Ali Kara
Electronics 2022, 11(2), 269; https://doi.org/10.3390/electronics11020269 - 14 Jan 2022
Cited by 5 | Viewed by 1559
Abstract
In the development of radiofrequency fingerprinting (RFF), one of the major challenges is to extract subtle and robust features from transmitted signals of wireless devices to be used in accurate identification of possible threats to the wireless network. To overcome this challenge, the [...] Read more.
In the development of radiofrequency fingerprinting (RFF), one of the major challenges is to extract subtle and robust features from transmitted signals of wireless devices to be used in accurate identification of possible threats to the wireless network. To overcome this challenge, the use of the transient region of the transmitted signals could be one of the best options. For an efficient transient-based RFF, it is also necessary to accurately and precisely estimate the transient region of the signal. Here, the most important difficulty can be attributed to the detection of the transient starting point. Thus, several methods have been developed to detect transient start in the literature. Among them, the energy criterion method based on the instantaneous amplitude characteristics (EC-a) was shown to be superior in a recent study. The study reported the performance of the EC-a method for a set of Wi-Fi signals captured from a particular Wi-Fi device brand. However, since the transient pattern varies according to the type of wireless device, the device diversity needs to be increased to achieve more reliable results. Therefore, this study is aimed at assessing the efficiency of the EC-a method across a large set of Wi-Fi signals captured from various Wi-Fi devices for the first time. To this end, Wi-Fi signals are first captured from smartphones of five brands, for a wide range of signal-to-noise ratio (SNR) values defined as low (−3 to 5 dB), medium (5 to 15 dB), and high (15 to 30 dB). Then, the performance of the EC-a method and well-known methods was comparatively assessed, and the efficiency of the EC-a method was verified in terms of detection accuracy. Full article
(This article belongs to the Section Networks)
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15 pages, 1668 KiB  
Article
Global Optimization in Robust Fractional Control of Uncertain Fractional Order Systems: A Thermal Application Using the STM32 Microcontroller
by Aymen Rhouma, Sami Hafsi and Faouzi Bouani
Electronics 2022, 11(2), 268; https://doi.org/10.3390/electronics11020268 - 14 Jan 2022
Cited by 1 | Viewed by 1849
Abstract
In this paper, we suggest an improvement to our previously undertaken approach. Briefly, this approach consisted of applying the robust fractional predictive control (RFPC) for a class of constrained fractional systems implementing the min–max optimization technique. The RFPC controller requires resolution of a [...] Read more.
In this paper, we suggest an improvement to our previously undertaken approach. Briefly, this approach consisted of applying the robust fractional predictive control (RFPC) for a class of constrained fractional systems implementing the min–max optimization technique. The RFPC controller requires resolution of a non-convex min–max optimization problem. The resolution of this problem, however, can only conduce to local solutions. The reason is simple: the objective function to be optimized is non-convex due to the presence of uncertainties. In the present work, we propose a global optimization-based RFPC controller for an uncertain fractional order system. A determinist global optimization method, namely, generalized geometric programming (GGP), is proposed to solve this problem for the uncertain fractional order system. The GGP method consists of converting a non-convex problem into a convex one via the application of variable changes. The technique of the convexification of this method is applied in line with the objective function to be optimized. Consequently, we obtained a new convex criterion and a convex problem. From an experimental point of view, we applied the proposed RFPC to a real thermal system using an STM32 microcontroller in order to control our thermal system. Full article
(This article belongs to the Section Systems & Control Engineering)
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21 pages, 2838 KiB  
Article
Analysis of Electric Energy Consumption Profiles Using a Machine Learning Approach: A Paraguayan Case Study
by Félix Morales, Miguel García-Torres, Gustavo Velázquez, Federico Daumas-Ladouce, Pedro E. Gardel-Sotomayor, Francisco Gómez-Vela, Federico Divina, José Luis Vázquez Noguera, Carlos Sauer Ayala, Diego P. Pinto-Roa, Julio César Mello-Román and David Becerra-Alonso
Electronics 2022, 11(2), 267; https://doi.org/10.3390/electronics11020267 - 14 Jan 2022
Cited by 6 | Viewed by 2376
Abstract
Correctly defining and grouping electrical feeders is of great importance for electrical system operators. In this paper, we compare two different clustering techniques, K-means and hierarchical agglomerative clustering, applied to real data from the east region of Paraguay. The raw data were pre-processed, [...] Read more.
Correctly defining and grouping electrical feeders is of great importance for electrical system operators. In this paper, we compare two different clustering techniques, K-means and hierarchical agglomerative clustering, applied to real data from the east region of Paraguay. The raw data were pre-processed, resulting in four data sets, namely, (i) a weekly feeder demand, (ii) a monthly feeder demand, (iii) a statistical feature set extracted from the original data and (iv) a seasonal and daily consumption feature set obtained considering the characteristics of the Paraguayan load curve. Considering the four data sets, two clustering algorithms, two distance metrics and five linkage criteria a total of 36 models with the Silhouette, Davies–Bouldin and Calinski–Harabasz index scores was assessed. The K-means algorithms with the seasonal feature data sets showed the best performance considering the Silhouette, Calinski–Harabasz and Davies–Bouldin validation index scores with a configuration of six clusters. Full article
(This article belongs to the Special Issue Applications of Machine Learning in Big Data)
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14 pages, 4953 KiB  
Article
Fourier Image Watermarking: Print-Cam Application
by Khadija Gourrame, Frederic Ros, Hassan Douzi, Rachid Harba and Rabia Riad
Electronics 2022, 11(2), 266; https://doi.org/10.3390/electronics11020266 - 14 Jan 2022
Cited by 2 | Viewed by 2044
Abstract
Digital image watermarking is an active research field since it provides protection, security, and authenticity of data. This paper presents development and implementation of a blind and robust watermarking application for ID images under a print-cam system. In the present case, the images [...] Read more.
Digital image watermarking is an active research field since it provides protection, security, and authenticity of data. This paper presents development and implementation of a blind and robust watermarking application for ID images under a print-cam system. In the present case, the images are watermarked and printed on ID cards and then detected freehandedly with a smartphone camera. In order to design an efficient and robust image watermarking application, the attacks produced in print-cam processes, such as geometric distortions, must be resolved. Accordingly, the proposed watermarking approach is applied in the Fourier domain. Then, a frame-based projective rectification is integrated to deal with geometric distortions by using detection of Hough lines. Moreover, better robustness against print-cam watermarking attacks was achieved compared with the existing methods, and an Android application was designed and implemented based on the proposed scheme. Full article
(This article belongs to the Section Computer Science & Engineering)
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18 pages, 1456 KiB  
Article
Driving Speed Estimation and Trapped Drivers’ Detection inside Tunnels Using Distributed MIMO Bluetooth Devices
by Sotirios Kontogiannis, Anestis Kastellos, George Kokkonis, Theodosios Gkamas and Christos Pikridas
Electronics 2022, 11(2), 265; https://doi.org/10.3390/electronics11020265 - 14 Jan 2022
Viewed by 1412
Abstract
Accidents in highway tunnels involving trucks carrying flammable cargoes can be dangerous, needing immediate confrontation to detect and safely evacuate the trapped people to lead them to the safety exits. Unfortunately, existing sensing technologies fail to detect and track trapped persons or moving [...] Read more.
Accidents in highway tunnels involving trucks carrying flammable cargoes can be dangerous, needing immediate confrontation to detect and safely evacuate the trapped people to lead them to the safety exits. Unfortunately, existing sensing technologies fail to detect and track trapped persons or moving vehicles inside tunnels in such an environment. This paper presents a distributed Bluetooth system architecture that uses detection equipment following a MIMO approach. The proposed equipment uses two long-range Bluetooth and one BLE transponder to locate vehicles and trapped people in motorway tunnels. Moreover, the detector’s parts and distributed architecture are analytically described, along with interfacing with the authors’ resources management system implementation. Furthermore, the authors also propose a speed detection process, based on classifier training, using RSSI input and speed calculations from the tunnel inductive loops as output, instead of the Friis equation with Kalman filtering steps. The proposed detector was experimentally placed at the Votonosi tunnel of the EGNATIA motorway in Greece, and its detection functionality was validated. Finally, the detector classification process accuracy is evaluated using feedback from the existing tunnel inductive loop detectors. According to the evaluation process, classifiers based on decision trees or random forests achieve the highest accuracy. Full article
(This article belongs to the Special Issue Applications for Distributed Networking Systems)
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19 pages, 5979 KiB  
Article
A High-Gain Multiphase Interleaved Differential Capacitor Clamped Boost Converter
by Dogga Raveendhra, Poojitha Rajana, Kalamchety Srinivasa Ravi Kumar, Praveen Jugge, Ramesh Devarapalli, Eugen Rusu and Hady H. Fayek
Electronics 2022, 11(2), 264; https://doi.org/10.3390/electronics11020264 - 14 Jan 2022
Cited by 4 | Viewed by 2076
Abstract
A step-up for a non-isolated interleaved differential capacitor clamped boost (IDCCB) DC–DC converter is proposed in this manuscript. Because of its ability to produce high voltage gains, it is used in high-power applications. This converter’s modelling and control design are applicable to any [...] Read more.
A step-up for a non-isolated interleaved differential capacitor clamped boost (IDCCB) DC–DC converter is proposed in this manuscript. Because of its ability to produce high voltage gains, it is used in high-power applications. This converter’s modelling and control design are applicable to any number of phases. A six-phase interleaved differential capacitor clamped boost prototype is tested in this work, with an input voltage of 60 V, an output voltage of 360 V, and a nominal output power of 2.2 kW. The components of the converter are placed and controlled in such a way that the output voltage is the sum of the two capacitor voltages and the input voltage, which is two times higher than the supply voltage when compared to a conventional interleaved differential dual-boost converter. This converter reduces the stress on the capacitor with reference to the conventional interleaved differential boost converter for the same conversion gain. This prototype is considered and the developed approach is applied, after which the experimental results are obtained. This converter has potential for application in areas such as renewable energy conversion and electric vehicles. Full article
(This article belongs to the Special Issue Power Converter Design, Control and Applications)
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30 pages, 9581 KiB  
Article
A Coarse-to-Fine Registration Approach for Point Cloud Data with Bipartite Graph Structure
by Munan Yuan, Xiru Li, Longle Cheng, Xiaofeng Li and Haibo Tan
Electronics 2022, 11(2), 263; https://doi.org/10.3390/electronics11020263 - 14 Jan 2022
Cited by 7 | Viewed by 2198
Abstract
Alignment is a critical aspect of point cloud data (PCD) processing, and we propose a coarse-to-fine registration method based on bipartite graph matching in this paper. After data pre-processing, the registration progress can be detailed as follows: Firstly, a top-tail (TT) strategy is [...] Read more.
Alignment is a critical aspect of point cloud data (PCD) processing, and we propose a coarse-to-fine registration method based on bipartite graph matching in this paper. After data pre-processing, the registration progress can be detailed as follows: Firstly, a top-tail (TT) strategy is designed to normalize and estimate the scale factor of two given PCD sets, which can combine with the coarse alignment process flexibly. Secondly, we utilize the 3D scale-invariant feature transform (3D SIFT) method to extract point features and adopt fast point feature histograms (FPFH) to describe corresponding feature points simultaneously. Thirdly, we construct a similarity weight matrix of the source and target point data sets with bipartite graph structure. Moreover, the similarity weight threshold is used to reject some bipartite graph matching error-point pairs, which determines the dependencies of two data sets and completes the coarse alignment process. Finally, we introduce the trimmed iterative closest point (TrICP) algorithm to perform fine registration. A series of extensive experiments have been conducted to validate that, compared with other algorithms based on ICP and several representative coarse-to-fine alignment methods, the registration accuracy and efficiency of our method are more stable and robust in various scenes and are especially more applicable with scale factors. Full article
(This article belongs to the Section Computer Science & Engineering)
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13 pages, 675 KiB  
Article
A Lightweight Learning Method for Stochastic Configuration Networks Using Non-Inverse Solution
by Jing Nan, Zhonghua Jian, Chuanfeng Ning and Wei Dai
Electronics 2022, 11(2), 262; https://doi.org/10.3390/electronics11020262 - 14 Jan 2022
Viewed by 1308
Abstract
Stochastic configuration networks (SCNs) face time-consuming issues when dealing with complex modeling tasks that usually require a mass of hidden nodes to build an enormous network. An important reason behind this issue is that SCNs always employ the Moore–Penrose generalized inverse method with [...] Read more.
Stochastic configuration networks (SCNs) face time-consuming issues when dealing with complex modeling tasks that usually require a mass of hidden nodes to build an enormous network. An important reason behind this issue is that SCNs always employ the Moore–Penrose generalized inverse method with high complexity to update the output weights in each increment. To tackle this problem, this paper proposes a lightweight SCNs, called L-SCNs. First, to avoid using the Moore–Penrose generalized inverse method, a positive definite equation is proposed to replace the over-determined equation, and the consistency of their solution is proved. Then, to reduce the complexity of calculating the output weight, a low complexity method based on Cholesky decomposition is proposed. The experimental results based on both the benchmark function approximation and real-world problems including regression and classification applications show that L-SCNs are sufficiently lightweight. Full article
(This article belongs to the Topic Machine and Deep Learning)
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12 pages, 7328 KiB  
Article
An N/M-Ratio All-Digital Clock Generator with a Pseudo-NMOS Comparator-Based Programmable Divider
by Jongsun Kim
Electronics 2022, 11(2), 261; https://doi.org/10.3390/electronics11020261 - 14 Jan 2022
Cited by 2 | Viewed by 2244
Abstract
A multiplying delay-locked loop (MDLL)-based all-digital clock generator with a programmable N/M-ratio frequency multiplication capability for digital SoC is presented. The proposed digital MDLL provides programmable N/M-ratio frequency multiplication using a new high-speed Pseudo-NMOS comparator-based programmable divider with small area and low power [...] Read more.
A multiplying delay-locked loop (MDLL)-based all-digital clock generator with a programmable N/M-ratio frequency multiplication capability for digital SoC is presented. The proposed digital MDLL provides programmable N/M-ratio frequency multiplication using a new high-speed Pseudo-NMOS comparator-based programmable divider with small area and low power consumption. The proposed MDLL clock generator can also provide a de-skew function by eliminating the phase offset problem caused by the propagation delay of the front divider in conventional N/M MDLL architectures. Fabricated in a 0.13-µm 1.2-V CMOS process, the proposed digital MDLL clock generates fully de-skewed output clock frequencies from 0.3 to 1.137 GHz with programmable N/M ratios of N = 1~32 and M = 1~16. It achieves a measured effective peak-to-peak jitter of 12 ps at 1.0 GHz when N/M = 8/1. It occupies an active area of only 0.034 mm2 and consumes a power of 10.3 mW at 1.0 GHz. Full article
(This article belongs to the Special Issue Mixed Signal Circuit Design)
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