alexandria engineering journal最新文献_第9页

A Müntz spectral method for solving fractional Fredholm integro–differential equations with convergence analysis 求解分数阶Fredholm积分微分方程的<s:1> ntz谱法及其收敛性分析

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-24 DOI: 10.1016/j.aej.2025.12.040

Jabbar Mahdy Hadaad , Masoud Allame , Habeeb Abed Kadhim Aal-Rkhais , Majid Tavassoli-Kajani

The solutions of fractional order equations might involve certain fractional-power terms that classical orthogonal polynomials connot match. Consequently, the advancement of effective numerical methods using generalized orthogonal polynomials such as fractional Jacobi, Müntz and fractional Chelyshkov functions enhances the precision of approximate solutions. This paper proposes a novel Müntz–Legendre spectral approach for a class of fractional Fredholm integro–differential equations with Caputo or Caputo–Fabrizio (CF) derivative. We first construct a matrix method that transforms the given linear problem to a system of linear algebraic equations. Then, we give a comprehensive convergence analysis of the proposed method. As opposed to the Caputo definition, the derivative of CF has no singularity at the end point, so it is expected that it is more convenient for numerical studies. Nonetheless, we propose a new approach to deal with the singularity in the definition of the Caputo derivative, efficiently. Some numerical examples are given and comparisons with other existing methods are provided to demonstrate the efficiency and accuracy of the proposed method. The extension of the proposed method to nonlinear problems via the linearization technique is also illustrated in an example.

分数阶方程的解可能涉及某些经典正交多项式无法匹配的分数次项。因此，利用分数阶Jacobi、m ntz和分数阶Chelyshkov函数等广义正交多项式的有效数值方法的进步提高了近似解的精度。针对一类具有Caputo或Caputo - fabrizio （CF）导数的分数阶Fredholm积分微分方程，提出了一种新的m ntz - legendre谱方法。我们首先构造一个矩阵方法，将给定的线性问题转化为线性代数方程组。然后，对该方法进行了全面的收敛性分析。与Caputo定义相反，CF的导数在端点处没有奇点，因此有望更方便于数值研究。尽管如此，我们还是提出了一种新的方法来有效地处理卡普托导数定义中的奇点。最后给出了数值算例，并与现有方法进行了比较，验证了该方法的有效性和准确性。通过实例说明了该方法通过线性化技术推广到非线性问题。

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引用次数: 0

Intelligent fault detection of zero-sample rotating machinery with embedded physical knowledge of vibration envelope and time-frequency analysis 基于振动包络物理知识和时频分析的零样本旋转机械故障智能检测

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-24 DOI: 10.1016/j.aej.2025.12.030

Guoqiang Li , Cheng Chen , Qijun Liu , Yiwei Cheng , Meirong Wei , Defeng Wu

Data-driven fault detection methods for rotating machinery have achieved impressive performance. Nevertheless, their practical deployment faces substantial challenges, including the high cost of acquiring fault data and inherent difficulties in constructing accurate models. This paper integrates domain knowledge of vibration signal analysis and proposes a physical knowledge-driven modeling method for rotating machinery fault detection with zero fault sample. First, Hilbert envelope analysis is introduced to attenuate the impact of fundamental frequency components. Subsequently, multi-dimensional evaluation metrics are used to select and filter multiple time-frequency analysis methods, thereby constructing a robust time-frequency knowledgebase. Then, three novel loss function driven by zero-fault samples is designed based on the differences between the selected time-frequency analysis methods and physical knowledge regarding the similarity among sliding window samples in monitoring signals. Finally, an end-to-end intelligent fault detection algorithm is developed based on the trained feature encoder and the introduced physical knowledge. The effectiveness of the proposed method is validated on both the rolling bearing experimental platform and the turbine experimental platform. The validation results demonstrate that the proposed method can achieve intelligent fault detection modelling without any fault samples, attaining fault detection test accuracies of 98.97 % and 96.19 % in the two respective case studies.

数据驱动的旋转机械故障检测方法已经取得了令人瞩目的成绩。然而，它们的实际部署面临着巨大的挑战，包括获取故障数据的高成本和构建准确模型的固有困难。结合振动信号分析的领域知识，提出了一种零故障样本下旋转机械故障检测的物理知识驱动建模方法。首先，引入希尔伯特包络分析来减弱基频分量的影响。然后，利用多维评价指标对多种时频分析方法进行选择和过滤，构建鲁棒的时频知识库。然后，基于所选时频分析方法与监测信号滑动窗样本相似性物理知识的差异，设计了三种新的零故障样本驱动的损失函数。最后，基于训练好的特征编码器和引入的物理知识，开发了端到端的智能故障检测算法。在滚动轴承实验平台和涡轮实验平台上验证了该方法的有效性。验证结果表明，该方法可以在不需要任何故障样本的情况下实现智能故障检测建模，在两个案例中分别获得了98.97 %和96.19 %的故障检测测试准确率。

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引用次数: 0

Decoupled feature extraction and correspondence modeling for deformable medical image registration using large kernel attention 基于大核关注的可变形医学图像配准解耦特征提取与对应建模

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-24 DOI: 10.1016/j.aej.2025.12.033

Zhou Zhou , Chenglong Fu , Chuang Wang , Ping Zhu , Kaijian Xia , Pengjiang Qian

Medical image registration aims to align images acquired at different times, perspectives, or modalities. Traditional deep learning approaches typically combine moving and fixed images as joint inputs, limiting the model’s ability to independently process image features and achieve accurate voxel-level correspondences. This paper introduces a novel registration framework, DELCA-Net, which decouples feature extraction from correspondence modeling using a large kernel attention (LKA) mechanism. DELCA-Net utilizes a dual-stream shared encoder that separately processes moving and fixed images, capturing long-range semantic dependencies. Additionally, we propose a Cross-Resolution Attention Refinement Module (CARM) that enhances multi-scale spatial correspondences via a coarse-to-fine fusion strategy, improving anatomical feature alignment across resolutions. Comprehensive experiments conducted on the OASIS and IXI datasets demonstrate that our method consistently improves registration accuracy while offering better interpretability and computational efficiency. On the IXI dataset, our model achieves a 1.2% increase in the DICE coefficient while requiring only 1.9% of the parameters of TransMorph. Additionally, the implementation of our method is publicly available at https://github.com/windandink/DELCA-NET.

医学图像配准的目的是对齐在不同时间、视角或模式下获得的图像。传统的深度学习方法通常将运动和固定图像作为联合输入，限制了模型独立处理图像特征和实现精确体素级对应的能力。本文介绍了一种新的配准框架DELCA-Net，该框架利用大核注意（large kernel attention， LKA）机制将特征提取与对应建模解耦。DELCA-Net采用双流共享编码器，分别处理移动和固定图像，捕获远程语义依赖。此外，我们提出了一个跨分辨率注意力细化模块（CARM），该模块通过粗到细的融合策略增强了多尺度空间对应，改善了跨分辨率的解剖特征对齐。在OASIS和IXI数据集上进行的综合实验表明，该方法在提高配准精度的同时具有更好的可解释性和计算效率。在IXI数据集上，我们的模型实现了DICE系数增加1.2%，而只需要1.9%的TransMorph参数。此外，我们的方法的实现可以在https://github.com/windandink/DELCA-NET上公开获得。

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引用次数: 0

Precise tunnel lining crack detection using multimodal fusion transformer and metaheuristic-optimized ResNet-50 基于多模态融合变压器和元启发式优化的ResNet-50的隧道衬砌裂纹精确检测

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-24 DOI: 10.1016/j.aej.2025.12.022

Zhen Chen , Zhixi Shen

Automated crack detection in tunnel linings is critical for ensuring infrastructure safety and facilitating efficient long-term maintenance. Manual inspection methods are typically slow, labour-intensive, and inconsistent, highlighting the necessity for advanced automated solutions. This research presents a Mathematical Multimodal Fusion Transformer-Based Optimization (MMFTO) framework that integrates multiple tunnel-lining image modalities to enable robust crack identification. The framework utilizes an optimized multimodal fusion transformer encoder to extract and combine complementary features that are often missed by unimodal systems. Hyper-parameter tuning is conducted using an Improved Piranha Foraging Optimization Algorithm (IPFOA) algorithm, followed by feature refinement with a Modified Sunflower Optimization Algorithm (MSFOA). Final classification is performed by a DeepResNet-50 model. The proposed MMFTO–MSFO–DeepResNet50 system is evaluated on a newly curated multimodal tunnel-lining dataset and compared with existing deep-learning and unimodal approaches. The model achieves 95 % accuracy, 92 % precision, 92 % F1-score, 91 % recall, a mean average precision (mAP) of 94.7 %, and a mean intersection over union (mIoU) of 93.6 %. Further evaluation on Crack500, Tunnel200, and DeepCrack datasets demonstrates strong robustness and generalizability. These results indicate that the framework offers significant potential for real-world tunnel monitoring and intelligent infrastructure management.

隧道衬砌的自动裂缝检测对于确保基础设施安全和促进有效的长期维护至关重要。人工检查方法通常是缓慢的，劳动密集型的，并且不一致的，突出了先进的自动化解决方案的必要性。本研究提出了一种基于数学多模态融合变压器的优化（MMFTO）框架，该框架集成了多种隧道衬砌图像模式，以实现鲁棒的裂缝识别。该框架利用优化的多模态融合变压器编码器来提取和组合单模态系统经常错过的互补特征。使用改进的食人鱼觅食优化算法（IPFOA）进行超参数调优，然后使用改进的向日葵优化算法（MSFOA）进行特征细化。最终分类由DeepResNet-50模型进行。提出的MMFTO-MSFO-DeepResNet50系统在新编制的多模式隧道衬里数据集上进行了评估，并与现有的深度学习和单模态方法进行了比较。该模型的准确率为95 %，精密度为92 %，F1-score为92 %，召回率为91 %，平均平均精度（mAP）为94.7 %，平均交联（mIoU）为93.6 %。对Crack500、Tunnel200和DeepCrack数据集的进一步评估显示出较强的鲁棒性和泛化性。这些结果表明，该框架为现实世界的隧道监测和智能基础设施管理提供了巨大的潜力。

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引用次数: 0

Can Dengue be controlled? Assessing vaccination and insecticide strategies with optimal control 登革热能被控制吗？以最优控制评估疫苗接种和杀虫剂策略

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-23 DOI: 10.1016/j.aej.2025.12.039

Kamrunnesa Mayeda , Sadia Akter Lima , Amin Ullah , Md. Kamrujjaman

Dengue fever is an enormous global public health burden, with millions of cases reported annually. In this paper, we have introduced a mathematical model that is capable of describing the transmission of dengue with hospitalization and vaccination and characterizing the infection’s dynamics. We calculate the basic reproduction number,

0 < R_{0} < 1

, that indicates the die-out of this infection. Initially, the fundamental mathematical findings are illustrated. Further, we compare different population dynamics with vaccination and without vaccination, and the results are satisfying and can also control the infection. We examine diverse characteristics’ impact on distinct population dynamics. In addition, the functions that are in charge of controlling this infection are used to come up with the best control strategies, which gives us the best control of characterization. We solve the model of optimal control numerically and do the correlative study between the control strategies: prevention and insecticide, which are the strongest options to rid a community of this disease. The finding suggests that including hospitalization and vaccination in the transmission model and control strategies (prevention and insecticide) can drastically cut down the infection of dengue fever as well as stop it from further spreading in a community.

登革热是一个巨大的全球公共卫生负担，每年报告的病例达数百万例。在本文中，我们介绍了一个数学模型，能够描述登革热的传播与住院和疫苗接种和表征感染的动态。我们计算基本繁殖数0<；R0<1，这表明这种感染的死亡。首先，说明了基本的数学发现。此外，我们比较了接种疫苗和未接种疫苗的不同种群动态，结果令人满意，也可以控制感染。我们研究了不同特征对不同种群动态的影响。此外，控制这种感染的功能被用来提出最好的控制策略，这给了我们最好的特征控制。对最优控制模型进行了数值求解，并对预防和杀虫剂这两种控制策略之间的相关性进行了研究，这两种控制策略是消除该疾病的最强选择。这一发现表明，在传播模式和控制策略（预防和杀虫剂）中纳入住院和疫苗接种可以大大减少登革热的感染，并阻止其在社区中进一步传播。

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引用次数: 0

Corrigendum to "Provide personalized programming learning for individuals based on large language models'" [Alex. Eng. J., 132 (2025) 396–406] “基于大型语言模型为个人提供个性化编程学习”的勘误表[Alex]。Eng。J., 132 (2025) 396-406]

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-23 DOI: 10.1016/j.aej.2025.12.045

Chong Li , Xin Lee , Xiaojin Wu

引用次数: 0

Modeling predator-prey dynamics with stochastic differential equations: Patterns of collective hunting and nonlinear predation effects 用随机微分方程模拟捕食者-猎物动力学：集体狩猎模式和非线性捕食效应

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-22 DOI: 10.1016/j.aej.2025.12.038

Junyi Qi, Tôn Việt Tạ

We investigate predator–prey school interactions in aquatic environments using a stochastic differential equation (SDE)-based, particle-level model that incorporates attraction, repulsion, alignment, and environmental noise. Two predation strategies — center attack and nearest attack — are examined to assess their effects on prey survival, predator efficiency, and group dynamics. Simulations reveal diverse emergent behaviors such as prey dispersal and regrouping, oscillatory predation with collective defense, and predator encirclement. Results show that collective hunting enhances capture efficiency compared to solitary attacks, but benefits diminish beyond a critical predator group size due to intra-predator competition. This work provides new insights into cooperative predation and introduces a generalizable SDE framework for analyzing predator–prey interactions.

研究人员利用基于随机微分方程（SDE）的粒子级模型研究了水生环境中捕食者-猎物群体的相互作用，该模型包含了吸引力、排斥力、对齐和环境噪声。研究了两种捕食策略——中心攻击和最近攻击——以评估它们对猎物生存、捕食者效率和群体动力学的影响。模拟结果揭示了多种突发性行为，如猎物分散和重组，振荡捕食和集体防御，以及捕食者包围。结果表明，与单独攻击相比，集体狩猎提高了捕获效率，但由于捕食者之间的竞争，超过了关键的捕食者群体规模，收益就会减少。这项工作为合作捕食提供了新的见解，并为分析捕食者-猎物相互作用引入了一个可推广的SDE框架。

引用次数: 0

Experimental and analytical studies on the compressive behaviors of a 3D-printed sand mold-cast S-CN connector in modular steel buildings 3d打印砂铸模S-CN连接器在模块化钢结构中的抗压性能试验与分析研究

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-22 DOI: 10.1016/j.aej.2025.12.013

Tran-Van Han , Jeong MoonSook , YongNam Kim , Tra Ngoc Sanh , Nguyen Huu Cuong , Kihak Lee

Steel modular construction offers advantages in speed, cost, and sustainability, but its adoption is constrained by connection efficiency. This study introduces the Samsung Connection Node (S-CN), a novel cast-steel connector fabricated using 3D-printed sand molds. Full-scale tests on roof nodes, floor nodes, the connector, and a beam–column assembly under axial compression were conducted, supported by finite element (FE) and analytical studies. Roof nodes carried 10% higher loads than floor nodes, while connector strength was governed by tie plate deformation and local buckling. Beam restraint improved load utilization, producing higher uniformity of strain. Code-based predictions (AISC 360-16 EN 1993-1-1) provided conservative agreement with experiments and FE. A mechanics-based model clarified that rim bearing controls global capacity, while yield-line mechanisms explain local deformation. Parametric studies highlighted the strong influence of node thickness and adverse effects of large openings or excessive column height. Supplementary FE analyses under combined axial–moment loading indicated a stable numerical response of the connector and suggested robustness under service-level eccentricities. A nonlinear pushover analysis of a corner subassembly suggested a ductility ratio of 7.5 with drift ratios below the ASCE 7 and Eurocode 8 near-collapse limits in the numerical model; these seismic-related findings are preliminary and require future experimental validation.

钢模块结构在速度、成本和可持续性方面具有优势，但其采用受到连接效率的限制。本研究介绍了三星连接节点（S-CN），这是一种使用3d打印砂模制造的新型铸钢连接器。在有限元（FE）和分析研究的支持下，对屋顶节点、地板节点、连接器和轴向压缩下的梁柱组件进行了全尺寸测试。顶节点承受的荷载比底板节点高10%，接头强度受拉板变形和局部屈曲的影响。梁约束提高了载荷利用率，产生更高的均匀应变。基于代码的预测（AISC 360-16 EN 1993-1-1）与实验和有限元结果保守一致。基于力学的模型表明，轮辋轴承控制全局能力，而屈服线机制解释局部变形。参数研究强调了节点厚度的强烈影响和大开口或过高柱高的不利影响。在联合轴矩载荷下的补充有限元分析表明，连接器的数值响应稳定，并且在服务级偏心下具有鲁棒性。对角部组件的非线性推覆分析表明，其塑性比为7.5，漂移比低于ASCE 7和欧洲规范8的接近崩溃极限；这些与地震有关的发现是初步的，需要未来的实验验证。

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引用次数: 0

Design, simulation, and experimental validation of metamaterials with direction-dependent stiffness 具有方向相关刚度的超材料的设计、模拟和实验验证

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-20 DOI: 10.1016/j.aej.2025.12.031

Hossein Rahimi , Mahdi Khajepour , Davood Rahmatabadi , Ghader Faraji , Mostafa Baghani , Daniel George , Majid Baniassadi

Mechanical metamaterials derive their functionality from geometry rather than composition, yet achieving experimentally validated three-dimensional direction-dependent stiffness (DDS) has remained challenging. This work introduces a 3D metamaterial unit cell with strong, tunable DDS, developed through a heuristic, gradient-free optimization framework that iteratively generated and refined geometries using finite element analysis. The final design features asymmetric internal struts and orientation-specific contact surfaces that activate bending- or stretching-dominated modes depending on loading direction. The unit cell and corresponding lattices were fabricated using high-resolution digital light processing (DLP) additive manufacturing and tested under compression along all three orthogonal axes. Simulations and experiments show excellent agreement (<1 % deviation), confirming distinct mechanical responses in the X, Y, and Z directions. The structure exhibits a stiffness increase above 350 % across deformation regions and up to 80 % contrast between its stiffest and most compliant orientations, while maintaining smooth force–displacement behavior with negligible stress concentrations. It also demonstrates substantial direction-dependent energy absorption, reaching several hundred joules in the stiffest orientation. These results establish a practical and manufacturable pathway toward architected materials with true 3D DDS, offering strong potential for exoskeletons, crash-protection systems, biomedical implants, and seismic-resistant components.

机械超材料的功能来源于几何形状，而不是成分，但实现实验验证的三维方向相关刚度（DDS）仍然具有挑战性。这项工作介绍了一种具有强大可调DDS的3D超材料单元格，该单元格通过启发式、无梯度优化框架开发，该框架使用有限元分析迭代生成和改进几何形状。最终设计的特点是不对称的内部支柱和方向特定的接触面，根据加载方向激活弯曲或拉伸主导模式。采用高分辨率数字光处理（DLP）增材制造技术制作了单元胞和相应的晶格，并沿着所有三个正交轴进行了压缩测试。模拟和实验显示了极好的一致性（<；1 %偏差），证实了X， Y和Z方向上不同的机械响应。结构在变形区域的刚度增加超过350 %，在其最刚度和最柔顺方向之间的对比高达80 %，同时保持平滑的力-位移行为，应力集中可以忽略不计。它还显示了大量的方向依赖的能量吸收，在最硬的方向上达到几百焦耳。这些结果为具有真正3D DDS的建筑材料建立了实用和可制造的途径，为外骨骼，碰撞保护系统，生物医学植入物和抗震组件提供了强大的潜力。

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引用次数: 0

Assessment of groundwater quantity and quality indexes and WQI determination for drinking and agricultural uses: Alborz Plain, Iran case study 用于饮用和农业用途的地下水数量和质量指标评价及WQI的确定：伊朗Alborz平原案例研究

IF 6.8 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

alexandria engineering journal

Pub Date : 2025-12-19 DOI: 10.1016/j.aej.2025.12.025

Mehdi Hedayatpour , Hamidreza Rabieifar , Hossein Hassanpour Darvishi , Reza Shirinabadi , Saeid Farokhizadeh

This study evaluates groundwater quantity and quality variations in Alborz Plain and assesses suitability for drinking and agriculture using the Water Quality Index (WQI). Data from 19 aquifers (2002–2023) were analyzed for key parameters: K⁺, Na⁺, Mg²⁺, Ca²⁺, SO₄²⁻, Cl⁻, HCO₃⁻, NO₃⁻, pH, EC, and TDS. Piper, Scholler, and Wilcox diagrams were prepared using Aq.QA and MATLAB to identify dominant facies and evaluate agricultural and drinking suitability. WQI results indicate “very good” quality in northwest and central regions, declining to “good” in east and improving in southeast. Dominant facies include Ca-HCO₃ or Mg-HCO₃ in northwest, center, and southeast, and Na-HCO₃ in east, with three aquifers exhibiting Na-SO₄, Na-Cl, and Ca-SO₄ facies. W1 and W3 aquifers are suitable for drinking despite high EC but show agricultural limitations in salt-sensitive areas. Long-term quality trends were assessed using Mann-Kendall test and Sen’s slope, while PCA and K-means clustering identified seven stable aquifer groups. SVR and Random Forest models accurately predicted TDS trends. Salinity is mainly influenced by regional geology, including evaporitic and dolomitic rocks, rather than proximity to sea. This integrated approach provides a practical framework for understanding groundwater dynamics and supporting sustainable management at regional and national levels.

本研究利用水质指数（WQI）评价了阿尔博斯平原地下水的数量和质量变化，并对饮用和农业适宜性进行了评价。对来自19个含水层（2002-2023年）的数据进行了关键参数分析：K⁺、Na⁺、Mg⁺、Ca⁺、SO₄²⁻、Cl⁻、HCO₃⁻、NO₃⁻、pH、EC和TDS。利用Aq.QA和MATLAB编制Piper、Scholler和Wilcox图，确定优势相，评价农业和饮用适宜性。WQI结果显示，西北和中部地区为“非常好”，东部地区为“好”，东南部地区为“好”。主要相为西北部、中部和东南部的Ca-HCO₃或Mg-HCO₃，东部的Na-HCO₃，3个含水层表现为Na-SO₄、Na-Cl和Ca-SO₄相。W1和W3含水层适合饮用，尽管高EC，但在盐敏感地区显示出农业限制。采用Mann-Kendall检验和Sen’s slope对含水层的长期质量趋势进行了评价，而PCA和K-means聚类则确定了7个稳定的含水层组。SVR和随机森林模型准确地预测了TDS的趋势。盐度主要受区域地质影响，包括蒸发岩和白云岩，而不是靠近海洋。这种综合方法为了解地下水动态和支持区域和国家一级的可持续管理提供了一个实用框架。

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引用次数: 0