alexandria engineering journal最新文献

{"title":"Directional spontaneous emission in a mono-mode waveguide with a circular cross section","authors":"S. Al-Awfi","doi":"10.1016/j.aej.2025.03.124","DOIUrl":"10.1016/j.aej.2025.03.124","url":null,"abstract":"<div><div>Exploring the spontaneous emission control of an excited two-level atom interacting with the vacuum within a circular waveguide surrounded by a perfect electric conductor is the main objective of this work. This type of emission is dependent on the intrinsic properties of the emitter, such as the emitter’s transition frequency and dipole moment direction, as well as the surrounding electromagnetic environment. Due to being statistical in nature, the fields do not have a well-defined phase, and thus the emission is considered incoherent or in an uncontrollable direction. We propose an approach to direct the emission from an atom embedded in a circular waveguide. To achieve this, multimode waveguides should be excluded because the total emission is simply presented in three orthogonal directions. In contrast, with mono-mode waveguides, the single photon transports in a single-mode waveguide coupled to a cavity embedded with an atom. Thus, the electric dipole moment vector is forced to take the direction of the only mode in which it is allowed to propagate. Besides giving rise to a single value for the emission, this also provides a way to control direction. Such waveguides have already been produced by recent advances in microfabrication technology.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 297-302"},"PeriodicalIF":6.2,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel model for investigating the thermal equilibrium characteristics of a high-speed train gearbox","authors":"Shuai Shao ,&nbsp;Kailin Zhang ,&nbsp;Yuan Yao ,&nbsp;Yi Liu ,&nbsp;Siqin Jin ,&nbsp;Zhengyang Wang","doi":"10.1016/j.aej.2025.03.100","DOIUrl":"10.1016/j.aej.2025.03.100","url":null,"abstract":"<div><div>Accurate analysis of the thermal equilibrium characteristics of high-speed train gearboxes can aid in preventing high-temperature malfunctions and ensuring the safe and efficient operation of trains. Owing to the complex heat transfer routes and interdependencies within the gearbox, establishing a precise thermal analysis model is essential. In this work, a finite element thermal network model is proposed to predict the temperature distribution of a gearbox. The moving particle semi-implicit method is used to determine the flow state of the lubricant and the convective heat transfer coefficients on the surfaces of the components. Power loss, which contributes to heat generation, is categorized into gear meshing, oil churning, and bearing friction. A thermal network model and finite element model for thermal analysis are subsequently developed based on heat transfer relationship, and data exchange between the two models is achieved through the BoundaryToFEM unit. The effects of the gear rotation speed, convective heat transfer coefficient between the components and lubricant, and heat transfer coefficient between the outer surface of the gearbox and ambient air on the thermal equilibrium are analyzed. The results indicate that when the input gear speed increases from 2104 rpm to 5259 rpm, the total power loss increases by 2159 W, and the heat balance temperature increases by approximately 53 °C. When the convective heat transfer coefficient between the components and lubricant varies from a 50 % reduction to a 50 % magnification, the thermal equilibrium temperature only changes by 1–2 °C. However, when t between the outer surface of the gearbox and ambient air undergoes the same variation process, the thermal equilibrium temperature decreases by approximately 82 °C. The full-scale gearbox running-in experiment shows that the predicted temperatures of the bearing cups remained within a deviation range of 2–5 % from the experimental values, and the maximum error of the lubricant temperature was 3.18 °C, which further verifies the accuracy and reliability of the proposed model.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 319-336"},"PeriodicalIF":6.2,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"WT-DSE-LSTM: A hybrid model for the multivariate prediction of dissolved oxygen","authors":"Xiao Xu,&nbsp;Chen Guo,&nbsp;Peng Wan,&nbsp;Hongbo Xu,&nbsp;Yang Yu,&nbsp;Jia Fan","doi":"10.1016/j.aej.2025.03.075","DOIUrl":"10.1016/j.aej.2025.03.075","url":null,"abstract":"<div><div>Dissolved oxygen (DO) is a critical indicator of water quality in freshwater lake ecosystems. To address the issues of difficulty in prediction of DO, a hybrid model (WT-DSE-LSTM) combined with the wavelet transform algorithm, the dual-squeeze-and-excitation module, and the long short-term memory network is proposed in this paper. The DSE module captures the long-term dependencies and enhances feature weights through the attention mechanism. The MAE, RMSE, and R² of DO prediction with the proposed model is 0.011, 0.015, and 0.9746, respectively. Furthermore, compared with the state-of-the-art models, the MAE, RMSE of the proposed one can be decreased by 94.09 % and 95.64 % and the R² of that can be increased by 50.49 %. The DSE module has demonstrated its potential to enhance multivariate time series prediction, which is of great significance for environmental protection and disaster reduction.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 285-296"},"PeriodicalIF":6.2,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy distribution strategy of power split marine hybrid energy storage propulsion system","authors":"Xiaojun Sun ,&nbsp;Fengmei Xin ,&nbsp;Gang Li","doi":"10.1016/j.aej.2025.03.108","DOIUrl":"10.1016/j.aej.2025.03.108","url":null,"abstract":"<div><div>The marine industry faces significant challenges, including the energy crisis and environmental pollution. In response, marine hybrid technology is regarded as an effective solution to address these issues. However, the overall performance of such systems is primarily governed by the energy management strategy. Therefore, this research proposes a marine hybrid energy management strategy (EMS) based on an adaptive migration butterfly optimization algorithm (AMBOA). Firstly, the performance index function is extended by adding a weighting term that suppresses the rate of change of the output power of the natural gas engine based on the Equivalent Consumption Minimization Strategy (ECMS), as well as maintaining the SOC penalty function to operate the powertrain in a quasi-static mode. Afterwards, Particle swarm algorithm is introduced to solve the problem that the butterfly optimisation algorithm is prone to fall into local optimum, and then the adaptive migration butterfly optimisation algorithm is formulated. Finally, the effectiveness of the proposed strategy is verified by the simulation platform and test bench. The results revealed that AMBOA-EMS effectively suppressed the frequent fluctuations of natural gas engine power compared to ECMS-EMS on the test stand, while saving 5.59 % of fuel while ensuring the power.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 238-256"},"PeriodicalIF":6.2,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamical behaviour of a two prey and one predator system with indirect effect and time delay","authors":"Yang Cao ,&nbsp;Peiyu Guo ,&nbsp;Luca Guerrini","doi":"10.1016/j.aej.2025.03.070","DOIUrl":"10.1016/j.aej.2025.03.070","url":null,"abstract":"<div><div>The effect of time delay on a population model consisting of two preys and one predator is investigated. The interactions within the system are primarily governed by a Holling type II functional response, which describes the relationship between the predation rate and the density of the first prey. Additionally, the model accounts for the indirect effects of predation, capturing the complex dynamics arising from these interactions. By incorporating time delay, the analysis explores how the temporal lag in responses affects the stability and behavior of the populations, such as reproduction, predation, or resource regeneration. This approach provides insights into the conditions under which populations coexist, oscillate, or collapse, offering a deeper understanding of predator–prey dynamics in ecosystems influenced by delayed feedback mechanisms. Conditions under which an equilibrium point loses stability and bifurcates into cyclic oscillations are established. Our study sheds light on the intricate relationship between time delay and the emergent dynamics in this ecological system. Finally, the validity of the theoretical results is verified through several numerical examples.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 257-264"},"PeriodicalIF":6.2,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The nonlocal Alice–Bob solutions for an extended combination of the Kadomtsev–Petviashvili3 and the Kadomtsev–Petviashvili4 equations","authors":"Yang-Kai Du ,&nbsp;Zheng-Yi Ma ,&nbsp;Li Cheng","doi":"10.1016/j.aej.2025.03.050","DOIUrl":"10.1016/j.aej.2025.03.050","url":null,"abstract":"<div><div>The paper first introduces the Alice–Bob system for the extended combination of the Kadomtsev–Petviashvili3 and the Kadomtsev–Petviashvili4 equations (cKP3-4), which is an integrable model. Based on the extended Bäcklund transformation, this system exists bilinear form after introducing an auxiliary variable. In order to construct the special explicit solution, that is, to satisfy the principle of the <span><math><mrow><msubsup><mrow><mover><mrow><mi>P</mi></mrow><mrow><mo>ˆ</mo></mrow></mover></mrow><mrow><mi>s</mi></mrow><mrow><mi>x</mi></mrow></msubsup><msubsup><mrow><mover><mrow><mi>P</mi></mrow><mrow><mo>ˆ</mo></mrow></mover></mrow><mrow><mi>s</mi></mrow><mrow><mi>y</mi></mrow></msubsup><msub><mrow><mover><mrow><mi>T</mi></mrow><mrow><mo>ˆ</mo></mrow></mover></mrow><mrow><mi>d</mi></mrow></msub><mi>A</mi><mo>=</mo><mi>B</mi></mrow></math></span> symmetry, we present one universal auxiliary function. Thereafter, this function can deduce various types of symmetry breaking solutions, which contain different soliton structures.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 273-284"},"PeriodicalIF":6.2,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced healthcare using generative AI for disabled people in Saudi Arabia","authors":"Geetanjali Rathee ,&nbsp;Sahil Garg ,&nbsp;Georges Kaddoum ,&nbsp;Samah M. Alzanin ,&nbsp;Mohammad Mehedi Hassan","doi":"10.1016/j.aej.2025.03.073","DOIUrl":"10.1016/j.aej.2025.03.073","url":null,"abstract":"<div><div>Saudi Arabia’s Vision 2030 prioritizes advances in healthcare to improve accessibility, improve medical services, and support people with disabilities. Despite the adoption of telemedicine and AI-driven healthcare solutions, disabled and elderly people continue to face challenges in accessing real-time medical services, receiving accurate diagnoses and independently navigate healthcare facilities. Current healthcare systems often struggle with delays, lack of personalization, and inefficiencies in medical data processing, limiting their effectiveness in providing inclusive and responsive healthcare. To address these challenges, this paper proposes an AI-powered healthcare framework that integrates Generative Artificial Intelligence (GAI), Reinforcement Learning from Human Feedback (RLHF), and the Analytic Network Process (ANP). RLHF enables AI models to learn and adapt based on real-time user feedback, ensuring a personalized and interactive healthcare experience. Meanwhile, ANP optimizes decision-making processes, allowing for faster, more accurate medical service delivery by considering multiple healthcare factors. This combined approach improves remote consultations, intelligent diagnostics, and seamless real-time interactions, significantly improving accessibility to healthcare for disabled individuals. The proposed framework is evaluated against existing AI-driven healthcare models. Results demonstrate that the system outperforms traditional methods, providing a faster, more reliable, and patient-centered healthcare experience. By combining GAI, RLHF, and ANP, this research offers a practical solution to improve healthcare accessibility for disabled individuals, aligning with the goals of Saudi Arabia’s Vision 2030.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 265-272"},"PeriodicalIF":6.2,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Air-ground collaborative networking for user-centric mobile following service in 6 G","authors":"Chuan’an Wang,&nbsp;Bo Kang","doi":"10.1016/j.aej.2025.03.132","DOIUrl":"10.1016/j.aej.2025.03.132","url":null,"abstract":"<div><div>With the evolution of 6 G networks, user-centric services have become a core objective, aiming to provide users with seamless, efficient, and personalized communication experiences. This paper introduces a novel approach leveraging dynamic air-to-ground base stations (BSs) coordination technology to enhance network performance and user experience for mobile users group, which is regarded as a big virtual user (BVU). The proposed framework constructs a dynamic ground BS group (BSG) to provide multiple parallel wireless backhaul links for Unmanned Aerial Vehicle (UAV), ensuring reliable connectivity as the UAV follow the BVU. A time-slot division method is employed, allowing the coordinated operation of UAV and the BSG to jointly provide data transmission services to the BVU. To address the challenges of mobility management, a dedicated signaling process is designed to enable seamless handovers and maintain service continuity. Through simulation and experimental verification, the effectiveness of this technology in improving BVU experience and network performance is proved, which provides a new idea and method for the development of 6 G network.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 231-237"},"PeriodicalIF":6.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Analyzing chaotic systems with multi-step methods: Theory and simulations” [Alex. Eng. J. 113 (2025) 516–534]","authors":"Meriem Mansouria Belhamiti ,&nbsp;Zoubir Dahmani ,&nbsp;Jehad Alzabut ,&nbsp;D.K. Almutairi ,&nbsp;Hasib Khan","doi":"10.1016/j.aej.2025.01.049","DOIUrl":"10.1016/j.aej.2025.01.049","url":null,"abstract":"","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"118 ","pages":"Page 711"},"PeriodicalIF":6.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843615","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":"Pixel-level pavement crack segmentation using UAV remote sensing images based on the ConvNeXt-UPerNet","authors":"Hatem Taha ,&nbsp;Hossam El-Habrouk ,&nbsp;Wael Bekheet ,&nbsp;Sayed El-Naghi ,&nbsp;Marwan Torki","doi":"10.1016/j.aej.2025.03.072","DOIUrl":"10.1016/j.aej.2025.03.072","url":null,"abstract":"<div><div>Cracks in the pavement are a common issue affecting transportation infrastructure, requiring timely detection and repair. Computer vision faces challenges in segmenting cracks from images due to complicated topologies, intensity inhomogeneity, poor contrast, and complex backgrounds. Currently, road crack detection relies on manual methods and road detection vehicles, which are inefficient, unsafe, and can cause traffic blockage. Using unmanned aerial vehicles (UAVs) for pavement crack detection could improve efficiency and economic benefits. However, cracks' thin and narrow appearance in UAV remote-sensing images also brings additional challenges and can hinder accurately identifying road cracks. To address these challenges, this paper proposes first, a UAV pavement crack dataset called DronePavSeg dataset. Secondly, the ConvNeXt-UPerNet network is a pixel-level pavement crack segmentation encoder-decoder. This model leverages the exceptional feature extraction capabilities of ConvNeXt as the encoder and UPerNet’s architecture as the decoder to learn the local and global semantic features of pavement cracks, improving segmentation accuracy. The ConvNeXt-Large-UPerNet model outperformed seven other SOTA segmentation models on the DronePavSeg dataset, achieving an average overall performance among the seven splits of mIoU of 79.73 %, Crack-IoU of 61.71 %, and F1-score of 76.03 % with zero-pixel tolerance. Compared to the second-best model (HRNet-FCN), the proposed model showed improvements of 0.41 % in mIoU, 0.74 % in Crack-IoU, and 0.59 % in F1-score. Qualitative examinations also confirmed its effectiveness and robustness in accurate pavement crack detection under complex pavement surfaces. Furthermore, we investigated the effect of different loss functions and various decoder architectures. Finally, the proposed model’s ability to generalize was tested on the two public benchmarks, CFD and Crack500 datasets. The results demonstrated that the ConvNeXt-UPerNet possesses excellent segmentation performance.</div></div>","PeriodicalId":7484,"journal":{"name":"alexandria engineering journal","volume":"124 ","pages":"Pages 147-169"},"PeriodicalIF":6.2,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}