Engineering Science and Technology-An International Journal-Jestech最新文献

{"title":"Rotational symmetric metamaterial structure of emblemed number connected with continuous transmission line for EM wave shielding applications","authors":"Md. Ismail Hossen ,&nbsp;Saif Hannan ,&nbsp;Mohammad Tariqul Islam ,&nbsp;Abdulmajeed M. Alenezi ,&nbsp;Mohamed S. Soliman","doi":"10.1016/j.jestch.2025.102200","DOIUrl":"10.1016/j.jestch.2025.102200","url":null,"abstract":"<div><div>Electromagnetic (EM) wave shielding in modern wireless systems encounters critical challenges, including polarization insensitivity, broadband operation, and compact design requirements. This work introduces a rotationally symmetric metamaterial absorber featuring emblem-shaped continuous transmission line resonators, specifically engineered to achieve high-efficiency absorption across the C, X, and Ku bands. The proposed design demonstrates remarkable absorption rates of 96.77 %, 99.68 %, 99.68 %, 99.70 %, 98.03 %, 99.68 %, and 99.98 % at resonance frequencies of 5.834 GHz, 7.192 GHz, 7.766 GHz, 10.65 GHz, 14.038 GHz, 15.34 GHz, and 15.62 GHz, respectively. Benefiting from rotational symmetry, the absorber maintains complete insensitivity to both co- and cross-polarized incident waves, with stable performance under oblique angles up to 90°. A maximum shielding effectiveness of 78 dB is achieved at the targeted frequencies, ensuring robust protection against EM interference. The compact unit cell (0.233λ × 0.233λ) exhibits near-zero permittivity, permeability, and refractive index with single-negative properties, further supporting efficient absorption within a minimal footprint. To validate the physical behavior, an equivalent RLC circuit model was developed in ADS, showing excellent agreement with CST simulations. Experimental verification using fabricated prototypes and Vector Network Analyzer measurements confirms the strong consistency between simulated and measured results. The novelty of this work lies in the integration of an emblem-shaped resonator with a continuous transmission line in a rotationally symmetric layout, enabling broadband absorption, polarization, and angle insensitivity, as well as high shielding effectiveness within a compact geometry. These features make the proposed absorber highly suitable for Wi-Fi, 5G, aerospace, defense radar, and stealth EM shielding applications.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102200"},"PeriodicalIF":5.4,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Secure electric vehicle charging station demand forecasting under adversarial and false data injection attacks","authors":"Najmul Alam,&nbsp;M.A. Rahman,&nbsp;Md. Arafat Hossain,&nbsp;Md. Rashidul Islam","doi":"10.1016/j.jestch.2025.102203","DOIUrl":"10.1016/j.jestch.2025.102203","url":null,"abstract":"<div><div>Forecasting the charging demand of electric vehicle charging stations (EVCSs) is critical for urban planning, resource allocation, policy development, and efficient grid management. However, reliance on sensor-collected data transmitted through various communication channels poses significant cybersecurity risks to forecasting models. This study evaluates the vulnerability of several commonly used forecasting models named random forest (RF), convolutional neural network (CNN), convolutional long short-term memory (ConvLSTM), and bidirectional convolutional long short-term memory (BiConvLSTM), under simulated cyber-attacks. Different attack scenarios, including fast gradient sign method (FGSM) and basic iterative method (BIM)-based adversarial attacks and scaling-based false data injection (FDI) attacks, are considered with varying attack volumes and perturbations. Metrics, such as root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE), are employed to assess and compare the accuracies of different models. Results indicate that forecasting models exhibit significant performance degradation under these cyber-attacks. As a countermeasure, adversarial training has been employed to mitigate the impact of such attacks and has proven to be highly effective. The experimental observations in this research elucidate the impact of cyber-attacks along with a defense mechanism to mitigate economic and technical risks to the EVCS, fostering the future development of accurate and cyber-resilient forecasting methodologies essential for advancing both academic and industrial domains of EVCS demand forecasting.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102203"},"PeriodicalIF":5.4,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and analysis of a continuously linear polarization agile antenna using microwave liquid crystal technology","authors":"Onur Hamza Karabey","doi":"10.1016/j.jestch.2025.102201","DOIUrl":"10.1016/j.jestch.2025.102201","url":null,"abstract":"<div><div>This paper presents the design and analysis of a continuously linear polarization-agile antenna based on Microwave Liquid Crystal (LC) technology. The proposed concept is specifically developed for Ku-band (e.g. 12 GHz) satellite communication applications, where systems typically operate with linear polarization and maintaining polarization alignment, referred to as skew angle adjustment, is critical for reliable on-the-move operation and for avoiding link loss. The antenna system incorporates a tunable feed network comprising two directional couplers and LC-based continuously tunable phase shifters. These feed a dual-fed microstrip patch antenna, enabling full-range linear polarization control over <span><math><mrow><mo>±</mo><mn>18</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>∘</mo></mrow></msup></mrow></math></span> by electronically adjusting the differential phase. The proposed tunable feed network is implemented using microwave LC technology to enable a fully passive architecture without requiring low-noise amplifiers. LC materials offer electrically tunable dielectric properties with inherently low dielectric loss, typically below 0.06 at frequencies beyond 10 GHz, and their loss tangent decreases with increasing frequency, making them particularly well-suited for Ku-band applications and beyond. In addition, LC materials benefit from a mature fabrication infrastructure originating from LC display manufacturing, allowing low-cost, large-area, and scalable production. Full-wave simulations at 12 GHz show that the system achieves a cross-polarization discrimination (XPD) better than 25 dB across the entire skew angle range. The LC-based phase shifters operate with only two bias voltages and provide 180° differential phase shift with an insertion loss below 2.3 dB, yielding a figure-of-merit of 80°/dB at 12 GHz. These results demonstrate the feasibility of the proposed design for low-loss, scalable, and reconfigurable antenna arrays in Ku-band and beyond satellite systems.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102201"},"PeriodicalIF":5.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Handover management for UAV communication in 5G networks: A systematic literature review","authors":"Azita Laily Yusof,&nbsp;Ahmad Zaki Aiman Abdul Rashid,&nbsp;Darmawaty Mohd Ali","doi":"10.1016/j.jestch.2025.102198","DOIUrl":"10.1016/j.jestch.2025.102198","url":null,"abstract":"<div><div>Within the last ten years, UAVs has captured both the academia’s and industry players attention due to their capabilities to be utilized in multiple applications. One of the most prominent functionalities that UAVs provided for multiple applications is communication. Due to these functionalities, UAVs are seen as a major player in the 5G/6G cellular networks. Extending the connectivity and communication through multiple devices is the main goal of the 5G/6G networks. In this context, UAVs can either be deployed as relays that receive signals from BS and transmit them to the UE, or the UAVs can be utilized as a BS that flies (UAV-BS) and supplies 5G/6G communication to the UEs on the ground. However, there are many issues that arise with UAV communication networks when trying to provide signal coverage to users. One of the issues is when utilizing UAV as a BS, the signal coverage’s quality might not be up to par due to the UAV’s high mobility characteristics, which also leads to the frequent handover experienced by the users on the ground. Frequent handovers, or “ping-pong” handovers, are not acceptable and can instigate other problems that reduce the quality of the signal, such as packet delays, or losses of packets. Efficient handover management in drone communication is the solution to this problem, and, thus, it requires to be applied to the UAV networks to sustain connectivity that is reliable and stable. This paper studies the handover management for UAV communication in 5G networks using the systematic literature review (SLR) technique for its methodology. Multiple topics related to the handover scenario in the UAV networks are being highlighted in this paper, alongside studies related to machine learning (ML) usage in making handover decisions. A total of 90 research papers that relate to the handover in UAV networks and that were published from 2019 to 2024 were chosen. The results from our studies show that machine learning is able to provide handover decision that are more efficient and robust than traditional/conventional methods of making handover decisions. Finally, several discussions based on several themes and the limitations of the studies were held.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102198"},"PeriodicalIF":5.4,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a fully prefabricated subway station using scale experimental modeling","authors":"Shupeng Wang ,&nbsp;Weigang Zhao ,&nbsp;Song Gao ,&nbsp;Kaize Xie ,&nbsp;Xianli Ding ,&nbsp;Juyang Wu","doi":"10.1016/j.jestch.2025.102181","DOIUrl":"10.1016/j.jestch.2025.102181","url":null,"abstract":"<div><div>The widespread adoption of prefabricated structures faces two critical challenges: ensuring reliable connection performance while maintaining assembly efficiency, and meeting the stringent precision requirements for mechanical connectors during installation. To address these issues, this study develops an innovative steel connector mechanical system for prefabricated subway stations and establishes a comprehensive evaluation methodology integrating assembly process simulation with structural performance assessment. Through scaled model tests combining static and cyclic pushover loading, the research demonstrates that the proposed connector successfully reconciles assembly efficiency with structural reliability, showing minimal displacement during assembly and substantial load-bearing capacity in service conditions. The prefabricated system exhibits excellent seismic performance through a controlled yield mechanism where localized damage at frame corners protects critical joints, maintaining structural integrity up to interstory drift ratios exceeding the limit of 1/250 specified by the Chinese code GB 50909–2014. These findings provide both a validated technical solution and a systematic evaluation framework for advancing prefabricated underground construction.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102181"},"PeriodicalIF":5.4,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy-efficient operation diagram optimization for high-speed trains considering energy storage device deployment","authors":"Yuzhao Zhang ,&nbsp;Shenyingze Gao ,&nbsp;Xuan Ji","doi":"10.1016/j.jestch.2025.102197","DOIUrl":"10.1016/j.jestch.2025.102197","url":null,"abstract":"<div><div>This study proposes an energy-efficient operation diagram optimization method for high-speed trains considering the deployment of energy storage devices. A hybrid PSO-SA algorithm is developed to solve the model, incorporating constraints such as departure times, dwell durations, and safety headways. Validated on the Baoji-Lanzhou section, results demonstrate an immediate regenerative energy utilization rate of 47.26 %, rising to 62.79 % with energy storage deployment. The hybrid algorithm reduces computation time by 74.59 % compared to traditional SA algorithm while maintaining solution quality. Compared with the GA algorithm, the optimal result obtained by the PSO-SA algorithm improved by 4.76 %. Economic analysis highlights prioritizing storage deployment in key power supply zones for optimal cost-effectiveness, offering actionable strategies for sustainable railway operations. This research provides theoretical and practical insights into energy-efficient high-speed rail systems.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102197"},"PeriodicalIF":5.4,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive review and prospect of transient damping methods for grid-forming virtual synchronous generator","authors":"Rongliang Shi ,&nbsp;Junming Li ,&nbsp;Xing Zhang ,&nbsp;Junhui Li ,&nbsp;Zheng Dong","doi":"10.1016/j.jestch.2025.102196","DOIUrl":"10.1016/j.jestch.2025.102196","url":null,"abstract":"<div><div>Transient damping has emerged as a key technique for mitigating active power oscillations in grid-forming virtual synchronous generator (GFVSG) systems, whether operating in grid-connected or parallel configurations. This study first elucidates the operating principles and primary functions of transient damping within GFVSG control, drawing on the electromechanical analogy and an energy reconstruction perspective. Typical transient damping approaches are then classified, followed by the proposal of a systematic parameter design strategy and an evaluation of their dynamic performance. Building on the limitations of existing research, this work contributes by identifying the research prospects, highlighting critical technical challenges, and suggesting structured pathways for further improvement. Finally, the paper provides a comprehensive synthesis intended to deepen understanding of the advantages and limitations of transient damping control in GFVSGs, while offering theoretical insights to support sustained advances in this field.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102196"},"PeriodicalIF":5.4,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A cost-effective embeddable algorithm for accelerometer-based fall detector","authors":"Abdullah Talha Sözer","doi":"10.1016/j.jestch.2025.102185","DOIUrl":"10.1016/j.jestch.2025.102185","url":null,"abstract":"<div><div>Falls, often causing injuries in older individuals, involve an unintentional descent to a lower level, like the ground. With the aging global population, addressing fall risks is crucial. Besides falls, delayed medical services post-fall may cause secondary complications. Automated fall detection (FD) systems can promptly identify falls and alert responders. Among automated FD systems, wearable sensor-based ones seem most viable for widespread use. These effectively distinguish falls from daily activities using machine learning techniques. However, their high computational complexity increases power consumption, requires powerful processors, and consequently raises costs. This underscores the need for affordable, embeddable algorithms. Developing highly accurate embeddable algorithms with manageable computational costs remains a current research challenge. This study introduces an algorithm tailored specifically for embedded systems, focusing on ease of implementation and reliance solely on accelerometer data. Empowered by a novel feature, the algorithm integrates thresholding and machine learning techniques, resulting in low computational complexity while maintaining highly effective FD capabilities. Evaluations of the algorithm on comprehensive public fall datasets, KFall and SisFall, demonstrate accuracies exceeding 99% and 97%, respectively. Furthermore, validation on real-world fall events from the FARSEEING dataset yielded an accuracy of 77.3%. Additionally, the proposed algorithm underwent real-time offline analysis on a low-power embedded device. The computational complexity of the proposed method is assessed by comparing it with another low-cost algorithm. Comparative evaluations against a low-cost algorithm, deep learning-based methods, and findings from the literature emphasize the superior performance and cost-effectiveness of this algorithm. Furthermore, the algorithm’s robustness is confirmed through testing at various sampling frequencies, highlighting its ability to achieve successful FD independent of sampling frequency.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102185"},"PeriodicalIF":5.4,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lateral and longitudinal human–machine co-driving of intelligent vehicle based on driving authorities game","authors":"Bin Tang,&nbsp;Jufang Yao,&nbsp;Haobin Jiang,&nbsp;Wei Mi","doi":"10.1016/j.jestch.2025.102187","DOIUrl":"10.1016/j.jestch.2025.102187","url":null,"abstract":"<div><div>Due to the current limitations of autonomous driving technology, human–machine co-driving is viewed as a viable and practical intermediary solution to bridge the gap between assisted driving and fully automated driving. To address challenges related to the allocation of lateral and longitudinal driving authority, as well as the interaction between the driver and the autonomous system, this paper proposes a game-sharing control strategy that operates at both the decision-making and control levels. At the decision level, a bargaining game-based approach is employed to allocate lateral and longitudinal driving authority dynamically, adjusting the distribution in accordance with a benefit function. At the control level, a lateral controller based on an extended game is developed to compute the optimal control manoeuvres by combining the driver’s inputs and reference tracking commands. This controller smoothly combines control inputs from both the driver and the automated system to ensure vehicle stability and minimize human–machine conflict. Simulation results show that, under a double lane-change scenario, the proposed strategy reduces yaw rate, lateral velocity, and lateral deviation by 0.35 rad/s, 0.6 m/s, and 0.6 m, respectively, compared with the fuzzy authority allocation method. Additionally, under cornering conditions, lateral deviation is reduced by 0.7 m. Finally, the proposed human–machine co-driving control strategy is verified by the experiment. The results indicate that the proposed strategy not only enhances trajectory tracking accuracy but also improves vehicle stability. Furthermore, by comparing the lateral and longitudinal authority allocation between the proposed and fuzzy strategies, it is evident that the approach significantly alleviates human–machine conflict, especially by reducing the frequent transfer of authority.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102187"},"PeriodicalIF":5.4,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soiling identification and forecasting in urban environment","authors":"Ivana Radonjić ,&nbsp;M. Asim Amin ,&nbsp;Milutin Petronijević ,&nbsp;Plamen Tsankov ,&nbsp;Martin Ćalasan","doi":"10.1016/j.jestch.2025.102188","DOIUrl":"10.1016/j.jestch.2025.102188","url":null,"abstract":"<div><div>Urban Photovoltaics (PVs) plays an important role in harnessing power generation for sustainable development, but its performance is impaired under an increasing level of environmental pollutants. This paper presents the development and verification of a Stacked Ensemble Learning (SEL) and Decision Trees (DTs) based algorithm for forecasting PV output under conditions of significant air pollution. It uses a small dataset for training and validation, including data on the production of an urban PV system and meteorological data commonly available from local weather services. The developed algorithm was tested on data collected from an urban location in Niš, Serbia, which is exposed to significant air pollution during the regular heating season, for three different panel mounting configurations. The SEL model achieves a near-zero error metric in predicting PV yield for vertical monocrystalline panels, maintaining high accuracy even under soiling, which is a key feature for real-world applications. Similar conclusions can be drawn for the cases of horizontal and optimally positioned panels. Using the developed SEL algorithm, it is shown that the soiling ratio obtained from the estimation of PV production of clean and soiled panels can be used as a reliable indicator for scheduling the optimal period for cleaning PV panels.</div></div>","PeriodicalId":48609,"journal":{"name":"Engineering Science and Technology-An International Journal-Jestech","volume":"71 ","pages":"Article 102188"},"PeriodicalIF":5.4,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}