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Journal of Energy Systems 2023年第1期7卷 106-120页

作者： Uysal, Latif Kasım Altın, Necmi Gazi University Faculty of Technology Automotive Engineering Department Ankara Turkey Gazi University Faculty of Technology Electrical - Electronic Engineering Department Ankara Turkey

Ever stricter emission regulations, declining petroleum resources, increasing pollution, and global warming triggered an interest in e-mobility. Although fully electrified transportation is targeted, hybrid electric vehicles have become attractive during this transition period due to reasons such as battery challenges, range anxiety, grid capacity, and charging infrastructure. Hybrid electrical vehicles require challenging energy management systems due to the increasing number of components and energy conversions. This paper aims to introduce a simple yet effective control scheme to control the battery state-of-charge (SOC) and regenerative braking of a hybrid electric vehicle. For this purpose, a fuzzy logic controller is developed, three inputs as the SOC, driver demand, and vehicle velocity are defined. Instead of torque or power requirement, which are commonly used as controller inputs in the literature, a more straightforward method is adopted by using the accelerator and brake pedal positions. The controller manages the engine power and regenerative braking intensity. A series hybrid electric vehicle model is created in the MATLAB/Simulink environment to validate the performance of the proposed controller. The proposed controller aims to keep the SOC between 30-40% after charge depleting mode, and ensures prevention of regenerative braking at high SOC values to prevent overcharging. Simulations have been performed according to NEDC and WLTC, show that the proposed controller is able to realize design objectives. © 2023 Published by peer-reviewed open access scientific journal.

关键词： Controllers

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Model-Free Adaptive Frequency Calibration for Voltage-Controlled Oscillators

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China Communications 2023年第1期20卷 199-208页

作者： Lianghui Xie Zhi Quan Osama Elnaha Qinglin Zhao Faculty of Information Technology Macao University of Science and TechnologyMacao 999078China College of Electronic Information Engineering Shenzhen UniversityShenzhen 518060China Department of Electrical Engineering Faculty of EngineeringAssiut UniversityEgypt

The operating frequency accuracy of the local oscillators is critical for the overall system performance in the communication ***,the high-precision oscillators could be too expensive for civil *** this paper,we propose a model-free adaptive frequency calibration framework for a voltage-controlled crystal oscillator(VCO)equipped with a time to digital converter(TDC),which can significantly improve the frequency accuracy of the VCO thus *** idea is to utilize a high-precision TDC to directly measure the VCO period which is then passed to a model-free method for working frequency *** advantage of this method is that the working frequency calibration employs the system history of input/output(I/O)data,instead of establishing an accurate VCO voltagecontrolled oscillator *** advantage is the lightweight calibration method with low complexity such that it can be implemented on an MCU with limited computation *** results show that the proposed calibration method can improve the frequency accuracy of a VCO from±20 ppm to±10 ppb,which indicates the promise of the modelfree adaptive frequency calibrator for VCOs.

关键词： frequency calibration carrier frequency offset model-free adaptive control wireless communication systems

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ECG Signal Classification of Cardiovascular Disorder using CWT and DCNN

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Journal of Biomedical Physics and engineering 2025年第1期15卷 77-92页

作者： Rahman, Tawfikur Ahommed, Rasel Deb, Nibedita Das, Utpal Kanti Moniruzzaman, Md. Bhuiyan, Md. Alamgir Sultana, Farzana Kausar, Md. Kamruzzaman Department of Electrical and Electronic Engineering Faculty of Engineering International University of Business Agriculture and Technology Uttara Dhaka 1230 Bangladesh Department of Agriculture International University of Business Agriculture and Technology Uttara Dhaka 1230 Bangladesh Department of Computer Science and Engineering Faculty of Engineering International University of Business Agriculture and Technology Uttara Dhaka 1230 Bangladesh

Background: Cardiovascular Diseases (CVD) requires precise and efficient diagnostic tools. The manual analysis of Electrocardiograms (ECGs) is labor-intensive, necessitating the development of automated methods to enhance diagnostic accuracy and efficiency. Objective: This research aimed to develop an automated ECG classification using Continuous Wavelet Transform (CWT) and Deep Convolutional Neural Network (DCNN), and transform 1D ECG signals into 2D spectrograms using CWT and train a DCNN to accurately detect abnormalities associated with CVD. The DCNN is trained on datasets from PhysioNet and the MIT-BIH arrhythmia dataset. The integrated CWT and DCNN enable simultaneous classification of multiple ECG abnormalities along-side normal signals. Material and Methods: This analytical observational research employed CWT to generate spectrograms from 1D ECG signals, as input to a DCNN trained on di-verse datasets. The model is evaluated using performance metrics, such as precision, specificity, recall, overall accuracy, and F1-score. Results: The proposed algorithm demonstrates remarkable performance metrics with a precision of 100% for normal signals, an average specificity of 100%, an average recall of 97.65%, an average overall accuracy of 98.67%, and an average F1-score of 98.81%. This model achieves an approximate average overall accuracy of 98.67%, highlighting its effectiveness in detecting ***: The integration of CWT and DCNN in ECG classification improves accuracy and classification capabilities, addressing the challenges with manual analy-sis. This algorithm can reduce misdiagnoses in primary care and enhance efficiency in larger medical institutions. By contributing to automated diagnostic tools for cardiovascular disorders, it can significantly improve healthcare practices in the field of CVD detection. © Journal of Biomedical Physics and engineering.

关键词： Wavelet transforms

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A Review of Machine Learning Techniques for Predicting Rainforest Watersheds and Enhancing Disaster Preparedness 1

A Review of Machine Learning Techniques for Predicting Rainf...

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1st IEEE International Conference on Communication engineering and Emerging Technologies, ICoCET 2024

作者： Pupathy, Sabrina Azemi, Saidatul Norlyana Amir, Amiza Universiti Malaysia Perlis Faculty of Electronic Engineering & Technology Perlis Malaysia Universiti Malaysia Perlis Faculty of Electronic Engineering & Technology Perlis Malaysia

ISBN: (纸本)9798331504144

Floods or rainforest watersheds are among the most frequent and destructive natural disasters, causing significant loss of life and economic disruption. Traditional flood modeling approaches often struggle to predict such events accurately, leading to a growing shift towards data-driven methods, particularly Machine Learning (ML) models. These models, leveraging historical climatic data, have emerged as powerful tools for forecasting floods with improved accuracy and cost-efficiency. This paper provides a comprehensive review of the latest advancements in ML-based flood forecasting, highlighting key algorithms and methodologies that have been benchmarked through qualitative analysis for their robustness, accuracy, effectiveness, and speed. The review also delves into major trends in the field, data decomposition, algorithm ensembles, and optimization techniques, which collectively enhance the predictive performance of ML models. By offering insights into the most promising approaches for both long-term and short-term flood or rainforest watershed prediction, this study serves as a valuable resource for hydrologists and climate scientists in selecting and developing effective flood forecasting systems. © 2024 IEEE.

关键词： Prediction models

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Electrical Tree Image Segmentation Using Hybrid Multi Scale Line Tracking Algorithm

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Computers, Materials & Continua 2023年第4期75卷 741-760页

作者： Mohd Annuar Isa Mohamad Nur Khairul Hafizi Rohani Baharuddin Ismail Mohamad Kamarol Jamil Muzamir Isa Afifah Shuhada Rosmi Mohd Aminudin Jamlos Wan Azani Mustafa Nurulbariah Idris Abdullahi Abubakar Mas’ud Faculty of Electrical Engineering&Technology Universiti Malaysia PerlisPerlisMalaysia School of Electrical and Electronic Engineering Universiti Sains MalaysiaPenangMalaysia Faculty of Electronic Engineering&Technology Universiti Malaysia PerlisPerlisMalaysia Department of Electrical and Electronics Engineering Jubail Industrial CollegeSaudi Arabia

Electrical trees are an aging mechanismmost associated with partial discharge(PD)activities in crosslinked polyethylene(XLPE)insulation of high-voltage(HV)*** of electrical tree structures gained considerable attention from researchers since a deep understanding of the tree morphology is required to develop new insulation ***-dimensional(2D)optical microscopy is primarily used to examine tree structures and propagation shapes with image segmentation ***,since electrical trees can emerge in different shapes such as bush-type or branch-type,treeing images are complicated to segment due to manifestation of convoluted tree branches,leading to a high misclassification rate during ***,this study proposed a new method for segmenting 2D electrical tree images based on the multi-scale line tracking algorithm(MSLTA)by integrating batch processing *** proposed method,h-MSLTA aims to provide accurate segmentation of electrical tree images obtained over a period of tree propagation observation under optical *** initial phase involves XLPE sample preparation and treeing image acquisition under real-time microscopy *** treeing images are then sampled and binarized in *** the next phase,segmentation of tree structures is performed using the h-MSLTA by utilizing batch processing in multiple instances of treeing ***,the comparative investigation has been conducted using standard performance assessment metrics,including accuracy,sensitivity,specificity,Dice coefficient and Matthew’s correlation coefficient(MCC).Based on segmentation performance evaluation against several established segmentation methods,h-MSLTA achieved better results of 95.43%accuracy,97.28%specificity,69.43%sensitivity rate with 23.38%and 24.16%average improvement in Dice coefficient and MCC score respectively over the original *** addition,h-MSLTA produced accurate measurement results of glo

关键词： Image segmentation multi-scale line tracking electrical tree partial discharge high-voltage cable

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Design of 3.5 GHz Cascode CMOS Class E Power Amplifier for 5G Application 1

Design of 3.5 GHz Cascode CMOS Class E Power Amplifier for 5...

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1st IEEE International Conference on Communication engineering and Emerging Technologies, ICoCET 2024

作者： Zainol Murad, Sohiful Anuar Hasan, Ahmad Fariz Bakar, Faizah Abu Universiti Malaysia Perlis Faculty of Electronic Engineering & Technology Perlis Malaysia Universiti Malaysia Perlis Faculty of Electronic Engineering & Technology Perlis Malaysia

ISBN: (纸本)9798331504144

The rapid growth of IoT and advancements in cellular technology have increased the demand for efficient data services, especially with 5G. The power amplifier (PA) is crucial in the RF front-end of transmitters, making its high efficiency vital for effective data transmission. This paper proposes a novel RF PA schematic designed to address these challenges by integrating a two-stage architecture comprising a driver stage and a power stage. The driver stage utilizes a capacitive feedback and pi-matching cascade Class AB topology with reverse body biasing to enhance power gain while minimizing power consumption. The power stage employs a cascade class E topology to achieve higher power added efficiency (PAE) is implemented using CMOS RF 0.18-μm technology. The output 1dB compression point (OP1dB) of 2.35 dBm and the saturated output power of 8.2 dBm were shown in the simulations of the suggested PA design, which showed a peak simulated PAE of 50.2% and resulting in an overall power gain of 23.4 dB. These results indicate that the proposed RF PA offers a highly efficient solution for 5G communication systems, effectively improving power amplifier performance without compromising critical parameters. © 2024 IEEE.

关键词： CMOS integrated circuits

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Compact Wideband Antenna Array with DGS-Based Metamaterial for Efficient Smartphone Communication and SAR Reduction

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Progress in Electromagnetics Research B 2025年 110卷 15-28页

作者： Megahed, Amany A. Hussein, Amr H. Al-Gburi, Ahmed Jamal Abdullah Elabd, Rania Hamdy Electronic and Communication Department Higher Institute of Engineering and Technology in New Damietta Damietta34517 Egypt Electronics and Electrical Communications Engineering Department Faculty of Engineering Tanta University Egypt Malacca Malaysia Electronics and Communications Engineering Department Faculty of Engineering Horus University Egypt New Damietta Egypt

This study investigates a high-gain, miniaturized antenna array featuring semicircular Defected Ground Structures (DGSs) based metamaterial designed for wideband smartphone applications. The antenna array, measuring 49 × 25 mm2 is constructed on an FR4 substrate with a dielectric constant of 4.3 and a thickness of 1.6 mm. The design incorporates two orthogonal antennas, each with a U-shaped radiating patch and a semicircular DGS to control bandwidth and reduce size. A T-shaped stub is positioned at the center of the U-shaped radiating area, with a star-shaped element attached to the leg of the T-shaped stub to enable wideband operation. The antenna demonstrates strong S11 performance, achieving approximately −38 dB at 5.8 GHz and −42 dB at 8.1 GHz, making it ideal for Sub-6 GHz and C-band applications. The proposed antenna array operates across a frequency range from 4 GHz to beyond 10 GHz, reaching a peak gain of 11 dBi and an efficiency of 95%. A time-domain analysis was conducted to verify radiation efficiency, and the specific absorption rate (SAR) is approximately 0.0475 for 1 g of tissue and 0.0101 for 10 g of tissue at 4.5 GHz, confirming the array's suitability for wideband smartphone devices within the target frequency band. The simulated and experimental results of the proposed antenna array show excellent agreement. © (2025), (Electromagnetics Academy). All rights reserved.

关键词： Tissue

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Dielectric Material Characterization for Reflectarray Antennas Designed at Sub-6GHz and Millimeter Wave Bands of 5G 16

Dielectric Material Characterization for Reflectarray Antenn...

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16th IEEE Malaysia International Conference on Communication, MICC 2023

作者： Khan, Sher Dali Abbasi, Muhammad Inam Ibrahim, Imran Mohd Sohu, Izhar Ahmed Khan, Sanaullah Faculty of Electrical and Electronic Engineering Technology Malaysia Faculty of Electronic and Computer Engineering Malaysia

ISBN: (纸本)9798350304343

The future compliance of reflectarray antenna necessitates a methodical examination of its primary traditional configurations to anticipate improvements. The current design, which utilizes microwave and millimeter wave frequencies, serves as a fundamental foundation for further investigation. This study offers a comparison and characterization of various dielectric substrates employed in Sub-6 GHz and millimeter wave reflectarray antenna, based on unit cells designed at 3.5 GHz and 28 GHz. The analysis utilizes a range of commercially accessible dielectric materials characterized by dielectric permittivity $({{\varepsilon _r}})$ values spanning 2 to 3.6 and loss tangent (tan) values ranging from 0.0009 to 0.001. The performance of different dielectric materials in the design of infinite reflectarray is assessed in terms of bandwidth and reflection loss, providing a comprehensive comparison. It is observed that the bandwidth of patch element unit cells at different levels exhibits significant variations depending on the material properties, with a 10% bandwidth range. Furthermore, it is illustrated that the reflectarray antenna's reflection loss can be deconstructed into dielectric and conductor losses, both contingent upon the material properties utilized in the design. This article presents a comparison of eleven distinct substrate materials that have the potential to result in disruptive designs for both the architecture and components, thereby impacting the performance of the reflectarray antenna. © 2023 IEEE.

关键词： Bandwidth

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Biocompatibility for In-Body Biotelemetry Devices: A Review of Antenna Design and Materials 1

Biocompatibility for In-Body Biotelemetry Devices: A Review ...

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1st IEEE International Conference on Communication engineering and Emerging Technologies, ICoCET 2024

作者： Jazimin Bin Mohd Idrus, Muhammad Afif Zulkefli, Muhammad Solihin Izzuddin Bin Wan Zahalan, Wan Muhammad Jack, Soh Ping Mat, Mohd Hafizuddin Faculty of Electronic Engineering & Technology Perlis02600 Arau Malaysia Oulu90014 Finland Faculty of Electronic Engineering & Technology Advanced Communiation Engineering Centre of Excellent Perlis Malaysia

ISBN: (纸本)9798331504144

In-body biotelemetry devices, especially implantable and ingestible antennas, have revolutionized healthcare by allowing remote physiological monitoring. This review examines two key methods: biocompatible encapsulation and the use of biocompatible substrates and superstrates for antenna biocompatibility. It discusses the challenges of electromagnetic interference in the human body and the importance of antennas for wireless connectivity in biomedical devices. The paper also explores the under-researched link between biocompatibility and antenna design, highlighting the role of materials like polydimethylsiloxane (PDMS), polyetheretherketone (PEEK), alumina, and zirconia in antenna optimization. It reviews operating frequency choices from the Medical Device Radio Communication Service band to Industrial Scientific and Medical bands, considering signal propagation, interference, and regulatory compliance. The research favors encapsulation across frequencies, especially 2400-2483.5 MHz, while the less-used substrate/superstrate method offers potential antenna performance benefits but requires a complex design process. The findings provide a comprehensive understanding of the complex relationship between biocompatibility and antenna design, guiding future research in this evolving field. © 2024 IEEE.

关键词： Biotelemetry

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Generation of OAM Waves and Analysis of Mode Purity for 5G Sub-6 GHz Applications

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Computers, Materials & Continua 2023年第1期74卷 2239-2259页

作者： Shehab Khan Noor Arif Mawardi Ismail Mohd Najib Mohd Yasin Mohamed Nasrun Osman Nurulazlina Ramli Ali H.Rambe J.Iqbal Advanced Communication Engineering(ACE) Centre of ExcellenceFaculty of Electronic Engineering TechnologyUniversiti Malaysia PerlisKangarPerlisMalaysia Centre for Advanced Electrical&Electronic System(CAEES)Faculty of Engineering Built Environment and Information TechnologySEGi University Petaling JayaSelangorMalaysia Department of Electrical Engineering Universitas Sumatera UtaraMedan20155Indonesia School of Electrical and Electronic Engineering Engineering CampusUniversiti Sains MalaysiaNibong Tebal14300PenangMalaysia Faculty of Engineering&Technology Gomal University29050 kpkPakistan

This article presents the generation of Orbital AngularMomentum(OAM)vortex waves with mode 1 using Uniform Circular Array(UCA)*** different designs,namely,UCA-1(4-element array antenna)and UCA-2(8-element array antenna),were designed and fabricated using FR-4 substrate to generate OAM mode 1 at 3.5 GHz(5G mid-band).The proposed antenna arrays comprised rectangular microstrip patch elements with inset fed *** elements were excited by a carefully designed feeding phase shift network to provide similar output energy at output ports with desired phase shift *** generated OAM waves were confirmed by measuring the null in the bore sight of their 2D radiation patterns,simulated phase distribution and intensity *** measurement results agree well with the simulation ***,a detailed mode purity analysis of the generated OAM waves was carried out considering different *** investigation found that the greater the number of elements,the higher the purity of the generated OAM *** with other previous works,the proposed antenna design of this paper is very simple to design and *** addition,the proposed antennas are compact in design even at lower frequency band with very wide bandwidth to meet the requirements of 5G mid-band applications.

关键词： Orbital angular momentum vortex waves fifth generation wireless communications uniform circular array antenna patch antenna

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