Applied Mathematical Modelling最新文献_第8页

Time-varying uncertain oil film pressure identification for journal bearing in wind turbine gearbox 风电齿轮箱滑动轴承时变不确定油膜压力辨识

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-14 DOI: 10.1016/j.apm.2026.116762

Wengui Mao , Wei Feng , jie Wang , Kai Li , Houjing Li , Zhao Xiao

In view of the fact that the oil film pressure of sliding bearing is repeatedly propagated by time-varying uncertain information, resulting in irregular fluctuations, which is difficult to meet the accuracy requirements of the health assessment of sliding bearing, A time-varying uncertain oil film pressure identification method based on the measured axis trajectory with small sample size is proposed. Firstly, the interval process model is used to describe the time-varying uncertainty information to reduce the dependence on the sample size of the axis trajectory, and the orthogonal series expansion method of the interval process is used to decouple the time-varying uncertainty problem into the linear superposition of the median and radius of the oil film pressure. The traditional distributed dynamic load identification method is used to calculate the median oil film pressure. The oil film pressure radius is obtained according to the covariance matrix mapping relation between the the axis trajectory and the oil film pressure. The effectiveness and economy of the proposed method are demonstrated by numerical example and experimental application.

针对滑动轴承油膜压力受时变不确定信息反复传播，产生不规则波动，难以满足滑动轴承健康评估精度要求的问题，提出了一种基于实测轴向轨迹的小样本量时变不确定油膜压力识别方法。首先，利用区间过程模型对时变不确定性信息进行描述，减少对轴向轨迹样本量的依赖，并利用区间过程的正交级数展开方法将时变不确定性问题解耦为油膜压力中值和半径的线性叠加；采用传统的分布式动载荷识别方法计算中位油膜压力。根据轴向轨迹与油膜压力的协方差矩阵映射关系，得到油膜压力半径。数值算例和实验应用验证了该方法的有效性和经济性。

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引用次数: 0

The evolution of fairness induced by marginal loss in ultimatum games within the networked population 网络群体中最后通牒博弈中边际损失诱导的公平演化

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-14 DOI: 10.1016/j.apm.2026.116753

Haojie Xu , Changwei Huang , Chengyi Xia

Fairness stands as a foundational principle in social and economic interactions, whereas in classical ultimatum game models it is generally grounded in linear, lossless payoffs that neglect the real-world costs of resource transfers. In this study, we extend the spatial ultimatum game by introducing a nonlinear loss function with two interpretable parameters: the loss intensity coefficient and the marginal loss sensitivity, which together capture diminishing marginal losses. Comprehensive numerical simulations reveal a pronounced optimization pattern: peak fairness appears when the loss intensity is large and the marginal loss sensitivity is moderate, a regime that simultaneously elevates average proposals and acceptance thresholds while damping long-term fluctuations. Mechanistically, the marginal loss effect imposes evolutionary pressure on unfair strategies, raising acceptance thresholds and compelling proposers to offer more equitable splits. Notably, the location of this high-fairness region remains robust across diverse network topologies, underscoring the generality of the marginal loss mechanism in fostering fairness. These findings contribute insights into the role of loss effects in promoting fairness, with potential applications in economic modeling, multi-agent systems, and the design of platforms that optimize social resource allocation.

公平是社会和经济互动的基本原则，而在经典的最后通牒博弈模型中，它通常建立在线性、无损失的回报基础上，忽略了资源转移的现实成本。本文通过引入具有两个可解释参数的非线性损失函数来扩展空间最后通牒博弈：损失强度系数和边际损失灵敏度，它们共同捕获边际损失递减。综合数值模拟揭示了一个明显的优化模式：峰值公平性出现在损失强度大而边际损失敏感性适中的情况下，这种制度同时提高了平均建议和接受阈值，同时抑制了长期波动。从机制上讲，边际损失效应对不公平策略施加了进化压力，提高了接受门槛，迫使提议者提供更公平的分配。值得注意的是，这种高公平区域的位置在不同的网络拓扑结构中保持稳健，强调了边际损失机制在促进公平方面的普遍性。这些发现有助于深入了解损失效应在促进公平中的作用，并在经济建模、多智能体系统和优化社会资源配置的平台设计中具有潜在的应用前景。

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引用次数: 0

A Levenberg-Marquardt-based optimization algorithm for multi-UAV path planning in complex media 基于levenberg - marquardt的复杂介质中多无人机路径规划优化算法

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-14 DOI: 10.1016/j.apm.2026.116761

Quancheng Pu, Lu Yang, Tieshan Li

Achieving effective 3D path planning for multi-UAV in complex media poses a significant challenge for current methods. To address this challenge, this paper proposes a novel approach. First, a cylindrical coordinate system is adopted for node representation, reducing the spatial complexity of the optimization variables and enhancing the algorithm’s solvability. Second, the UAV path planning cost function is improved by decoupling costs from environmental parameters, thereby enhancing adaptability to various tasks. Drawing inspiration from the Levenberg-Marquardt algorithm, a new meta-heuristic optimization algorithm is developed, which integrates global search, local exploitation, and mutation strategies. This algorithm offers rapid optimization and robust global search capabilities, making it well-suited for complex problems such as multi-UAV path planning. To validate the method, comprehensive comparative experiments were conducted: (1) an analysis of node representations across three coordinate systems demonstrated that cylindrical coordinates reduce the search space, improve performance, and shorten computation time; (2) tests on CEC 2005 benchmark functions against advanced algorithms showed superior global optimization accuracy and convergence speed; and (3) simulations of single- and multi-UAV path planning in large-scale complex environments confirmed the method’s effectiveness and robustness. The proposed method holds promising potential for application in other practical optimization domains.

实现复杂介质中多无人机的有效三维路径规划对现有方法提出了重大挑战。为了解决这一挑战，本文提出了一种新的方法。首先，采用圆柱坐标系进行节点表示，降低了优化变量的空间复杂度，提高了算法的可解性；其次，通过将成本与环境参数解耦，改进了无人机路径规划成本函数，增强了对各种任务的适应性；在Levenberg-Marquardt算法的启发下，提出了一种集全局搜索、局部开发和突变策略于一体的元启发式优化算法。该算法具有快速优化和鲁棒的全局搜索能力，适用于多无人机路径规划等复杂问题。为了验证该方法，进行了全面的对比实验：(1)通过对三种坐标系下节点表示的分析表明，柱坐标减少了搜索空间，提高了性能，缩短了计算时间；(2)在CEC 2005基准函数上对先进算法的全局优化精度和收敛速度进行了测试；(3)对大尺度复杂环境下的单无人机和多无人机路径规划进行仿真，验证了该方法的有效性和鲁棒性。该方法在其他实际优化领域具有广阔的应用前景。

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引用次数: 0

Applicability of Shear Horizontal guided waves in non-classical continuum theory and calibration of higher-order mode scale parameters 剪切水平导波在非经典连续介质理论中的适用性及高阶模态尺度参数的标定

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-14 DOI: 10.1016/j.apm.2026.116763

Chuang Yang, Jiangong Yu, Zhi Li, Xiaoming Zhang

As core theories of non-classical continuum theory, the nonlocal, nonlocal strain gradient theory, and Gurtin-Murdoch surface elasticity theories have yet to resolve how to determine the high-order modal scale parameters and applicability in wave propagation. In this study, molecular dynamics simulations combined with a GA-BP neural network were used to calibrate the scale parameters of higher-order Shear Horizontal (SH) modes and investigate the applicability of these theories. The results show the nonlocal and nonlocal strain gradient theories exhibit good applicability, whereas the Gurtin-Murdoch surface elasticity theory alone is inapplicable to higher-order modes. However, when combined with the nonlocal theory, it can accurately describe them. Moreover, the scale parameters exhibit clear differences between higher- and lower-order modes, with the scale parameters of higher-order modes being smaller than those of lower-order modes. Theoretical predictions based on the calibrated parameters agree well with MD simulations, with errors below 2%. These findings provide a basis for evaluating the applicability of non-classical continuum theories and guiding the design of sensitive nanodevices.

作为非经典连续介质理论的核心理论，非局部应变梯度理论、非局部应变梯度理论和Gurtin-Murdoch表面弹性理论如何确定高阶模态尺度参数及其在波传播中的适用性还有待解决。本研究采用分子动力学模拟与GA-BP神经网络相结合的方法，对高阶剪切水平（SH）模态的尺度参数进行了标定，并探讨了这些理论的适用性。结果表明，非局部应变梯度理论和非局部应变梯度理论具有较好的适用性，而单独的Gurtin-Murdoch表面弹性理论不适用于高阶模态。然而，当与非定域理论相结合时，它可以准确地描述它们。高阶模态和低阶模态的尺度参数差异明显，高阶模态的尺度参数小于低阶模态的尺度参数。基于校准参数的理论预测与MD模拟吻合良好，误差低于2%。这些发现为评价非经典连续介质理论的适用性和指导敏感纳米器件的设计提供了依据。

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引用次数: 0

A hybrid bayesian calibrated grey model for robust lubricant wear debris forecasting 基于混合贝叶斯校正灰色模型的润滑油磨损磨损预测

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-14 DOI: 10.1016/j.apm.2026.116776

Xiaoyu Yang , Zhigeng Fang

To address the challenges of data fluctuations and sparse sampling in prognostic and health management, this paper proposes a hybrid Bayesian-calibrated grey model that enhances prediction robustness and accuracy by systematically integrating prior evolution knowledge from homogeneous historical samples into the grey modeling framework. The model incorporates a Bayesian calibration mechanism implemented through three key steps: first, constructing a prior distribution for the development coefficient based on historically similar samples; second, deriving a posterior estimate of the development coefficient via Bayesian inference to mitigate the impact of sampling data fluctuations; third, obtaining the prediction results from the general solution of the grey differential equation. The model’s performance is evaluated through numerical experiments and a practical task of predicting lubricant iron content in wind turbine gearboxes. Experimental results demonstrate that the proposed model exhibits excellent anti-interference capability, significantly improves prediction accuracy and robustness compared to conventional grey models, while also providing reliable interval forecasts. This framework offers a novel and robust solution for forecasting under data-sparse conditions, advancing the application of grey models in engineering prognostics.

为了解决预测和健康管理中数据波动和稀疏采样的挑战，本文提出了一种混合贝叶斯校准灰色模型，该模型通过系统地将来自同质历史样本的先验进化知识集成到灰色建模框架中，提高了预测的鲁棒性和准确性。该模型采用贝叶斯校准机制，通过三个关键步骤实现：首先，基于历史相似样本构建发展系数的先验分布；其次，通过贝叶斯推理得到发展系数的后验估计，以减轻抽样数据波动的影响；第三，由灰色微分方程的通解得到预测结果。通过数值实验和风电齿轮箱润滑油铁含量预测的实际任务，对该模型的性能进行了评价。实验结果表明，该模型具有良好的抗干扰能力，与传统灰色模型相比，预测精度和鲁棒性显著提高，同时提供了可靠的区间预测。该框架为数据稀疏条件下的预测提供了一种新颖、鲁棒的解决方案，促进了灰色模型在工程预测中的应用。

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引用次数: 0

Fractal invariance-constrained deep learning for spatial-temporal prediction of turbulent flows 湍流时空预测的分形不变性约束深度学习

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-13 DOI: 10.1016/j.apm.2026.116754

Min Luo , Jiaxin Wu

Spatial-temporal prediction of turbulence remains an important and challenging task in fluid dynamics. This study proposes a fractal invariance-constrained deep learning model, which is characterized by two novel components: (1) a main network equipped with a multi-scale feature reuse mechanism for reduced-order modelling and flow state prediction; and (2) a physical constraint derived from the fractal theory to quantify and regularize scale-invariant self-similarities of fluid dynamic systems. The proposed physical constraint is then embedded into the main network, leading to the proposed model that integrates the efficiency of a deep learning network and the accuracy of physical constraints for flow state prediction. Moreover, a novel learning strategy is proposed to learn turbulence fluctuations at high frequencies and improve the training efficiency of the proposed model. Results on five self-affine fractal images and two turbulence cases demonstrate that the proposed model has achieved a threefold higher efficiency and 40 times improvement in prediction accuracy compared to the purely data-driven methods. Particularly in reconstructing physical quantities, such as the energy spectra and probability density functions of flow fields, the proposed model achieves up to a hundredfold improvement in accuracy. These results highlight the role of constraint in guiding the main network to accurately capture scale invariances and predict kinetic energy within high-frequency subranges.

湍流的时空预测仍然是流体动力学中一项重要而富有挑战性的任务。本文提出了一种分形不变性约束深度学习模型，该模型具有两个新的组成部分：(1)主网络具有多尺度特征重用机制，用于降阶建模和流状态预测；(2)由分形理论导出的物理约束，用于量化和正则化流体动力系统的尺度不变自相似。然后将所提出的物理约束嵌入到主网络中，从而产生将深度学习网络的效率和流状态预测物理约束的准确性集成在一起的所提出的模型。此外，提出了一种新的学习策略来学习高频湍流波动，提高了模型的训练效率。在5张自仿射分形图像和2个湍流情况下的实验结果表明，该模型的预测效率比纯数据驱动的方法提高了3倍，预测精度提高了40倍。特别是在重建物理量时，如流场的能谱和概率密度函数，该模型的精度提高了一百倍。这些结果突出了约束在指导主网络准确捕获尺度不变性和预测高频子范围内动能方面的作用。

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引用次数: 0

Autonomous drone model: A mathematical study 自主无人机模型：一个数学研究

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-12 DOI: 10.1016/j.apm.2026.116750

Agata Lonc, Barbara Domżała, Monika J. Piotrowska

In this paper, we propose a novel model that describes the movement of a group of n drones in an air corridor, where overtaking is allowed. The model combines main ideas from car-following traffic models with macroscopic concepts, such as the congestion of the air corridor. Furthermore, it incorporates the heterogeneity of drones through varying parameters, such as size, maximum velocity, and maximum acceleration. Apart from interactions between drones, the model allows for the wind compound to be taken into account. We prove the essential mathematical properties of the proposed model. Moreover, we derive the necessary conditions for all drones to move at the same constant speed and analyse the stability of such a situation. The process of overtaking is examined in two examples. In particular, we present all possible long-term scenarios for a special case of two drones. Then, we analyse the model with non-zero wind force, showing that wind strongly affects the dynamics of the whole system. Finally, we perform numerical simulations to illustrate the theoretical properties of the model.

在本文中，我们提出了一个新的模型来描述一组n架无人机在允许超车的空中走廊中的运动。该模型结合了汽车跟随交通模型的主要思想和宏观概念，如空中走廊的拥堵。此外，它通过不同的参数，如尺寸、最大速度和最大加速度，结合了无人机的异质性。除了无人机之间的相互作用外，该模型还考虑了风的化合物。我们证明了所提模型的基本数学性质。此外，我们推导了所有无人机以相同恒定速度移动的必要条件，并分析了这种情况的稳定性。通过两个实例分析了超车过程。特别是，我们提出了所有可能的长期情况下，两个无人机的特殊情况。然后，我们分析了非零风力的模型，表明风对整个系统的动力学影响很大。最后，我们进行了数值模拟来说明模型的理论性质。

引用次数: 0

Adaptive finite-time second-order sliding mode attitude control for fixed-wing UAVs 固定翼无人机自适应有限时间二阶滑模姿态控制

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-11 DOI: 10.1016/j.apm.2026.116745

MohammadReza Ebrahimpour , Mihai Lungu , Saleh Mobayen , Rui Wang

Fixed-wing unmanned aerial vehicles are widely used in applications such as environmental monitoring, surveillance, and aerial mapping, where accurate attitude control is essential for flight stability and mission success. However, external disturbances, parametric uncertainties, and actuator dynamics with saturation and faults pose significant challenges to control performance and reliability. This paper proposes a robust and adaptive attitude-control strategy that addresses these challenges while maintaining low computational complexity. A fast finite-time second-order sliding-mode control method is designed by combining backstepping and sliding mode control techniques, providing enhanced robustness and effective suppression of chattering. The method is further augmented with an adaptive radial basis function neural network law and an auxiliary compensation system: the adaptive law updates only a single learning parameter, reducing computational load by approximately 53 % compared with conventional neural network–based adaptive methods, while the auxiliary system mitigates actuator saturation. Numerical simulations demonstrate that the proposed methods reduce tracking errors by up to 77 % relative to conventional approaches, maintain performance under severe disturbances and uncertainties, and achieve low computational overhead, highlighting their practical applicability in real-world unmanned aerial vehicle operations.

固定翼无人机广泛应用于环境监测、监视和航空测绘等领域，精确的姿态控制对飞行稳定和任务成功至关重要。然而，外部干扰、参数不确定性以及执行器的饱和和故障动力学对控制性能和可靠性提出了重大挑战。本文提出了一种鲁棒的自适应姿态控制策略，以解决这些挑战，同时保持较低的计算复杂度。将反步控制技术与滑模控制技术相结合，设计了一种快速有限时间二阶滑模控制方法，增强了鲁棒性，有效抑制了抖振。该方法进一步增强了自适应径向基函数神经网络律和辅助补偿系统：自适应律只更新单个学习参数，与传统的基于神经网络的自适应方法相比，计算负荷减少了约53%，而辅助系统减轻了执行器的饱和。数值模拟表明，与传统方法相比，所提出的方法将跟踪误差降低了77%，在严重干扰和不确定性下保持性能，并且实现了较低的计算开销，突出了其在实际无人机操作中的实用性。

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引用次数: 0

Recursive modeling and trajectory optimization of space manipulator mounted on flexible structure 柔性结构空间机械臂递归建模与轨迹优化

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-11 DOI: 10.1016/j.apm.2026.116741

Yixing Gong, Hao Wen

Manipulators mounted on flexible bases are widely used in space missions. However, their control is complicated by the dynamic coupling between the manipulator and the flexible base. The control objective of such a system is to simultaneously suppress the base’s vibrations and control the manipulator to move to its target configuration. Most existing approaches either use simplified mass-spring models that fail to capture complex dynamics or high-fidelity methods that are computationally expensive. This study focuses on manipulators mounted on large slender truss structures and presents a trajectory optimization scheme to accomplish the control task. To simplify analysis, the large slender truss is modeled as an Euler-Bernoulli beam with dynamics derived via the finite element method. For efficiency, the manipulator-truss dynamics is derived using recursive modeling. Subsequently, a trajectory optimization problem is formulated, in which the system’s implicit dynamics are employed as constraints. Afterwards, The trajectory optimization problem is subsequently transcribed into a nonlinear programming formulation and solved to generate optimal trajectories for feedback-based online tracking. Finally, numerical simulations using an Absolute Nodal Coordinate Formulation beam as reference demonstrate the effectiveness of the proposed trajectory optimization scheme, achieving the control tasks in both Absolute Nodal Coordinate Formulation- and Euler-Bernoulli-based models.

安装在柔性基座上的机械臂在航天任务中有着广泛的应用。然而，由于机械臂与柔性基座之间的动态耦合，使其控制变得复杂。该系统的控制目标是在抑制基座振动的同时控制机械手运动到目标位形。大多数现有的方法要么使用简化的质量-弹簧模型，无法捕获复杂的动力学，要么使用计算成本高的高保真方法。针对安装在大型细长桁架结构上的机械臂，提出了一种轨迹优化方案来完成控制任务。为了简化分析，将大型细长桁架建模为欧拉-伯努利梁，并通过有限元法推导其动力学。为提高效率，采用递归建模方法推导了机械臂桁架动力学。在此基础上，提出了以系统隐式动力学为约束条件的轨迹优化问题。然后，将轨迹优化问题转化为非线性规划公式求解，生成基于反馈的在线跟踪的最优轨迹。最后，以绝对节点坐标公式光束为参考的数值仿真验证了所提出的轨迹优化方案的有效性，实现了绝对节点坐标公式和基于euler - bernoulli模型的控制任务。

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引用次数: 0

Hodograph transformation and cuspon localized wave solutions for the modified complex short pulse equation 修正复短脉冲方程的矢状变换与cuson局域波解

IF 4.4 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Applied Mathematical Modelling

Pub Date : 2026-01-10 DOI: 10.1016/j.apm.2026.116747

Jian-Yu Liu, Xiao-Yong Wen

This work employs the modified complex short pulse equation to model the nonlinear propagation of ultrashort optical pulses in fibers. Based on the hodograph transformation and the generalized Darboux transformation, four types of position-controlled cuspon localized wave solutions are constructed, comprising cuspon semi-rational soliton, cuspon rogue wave, cuspon periodic wave, and their cuspon hybrid interaction solutions, all of which are illustrated graphically. Unlike traditional single-valued smooth structures, we demonstrate single-valued, non-smooth cuspon-type localized wave structures with sharp peaks. Furthermore, by adjusting specific parameters, we can effectively control the spatial positions and shapes of these localized wave solutions. These results not only enrich the understanding of cuspon localized wave structures but also offer valuable tools for interpreting ultrashort optical pulse propagation under nonlinear conditions.

本文采用修正的复短脉冲方程来模拟超短光脉冲在光纤中的非线性传播。基于hodograph变换和广义Darboux变换，构造了四种位置控制的cuspon局域波解，包括cuspon半有理孤子、cuspon流氓波、cuspon周期波及其cuspon混合相互作用解，并给出了图解。与传统的单值光滑结构不同，我们展示了具有尖峰的单值非光滑cuscustype局域波结构。此外，通过调整特定参数，我们可以有效地控制这些局部波解的空间位置和形状。这些结果不仅丰富了对cuspon局域波结构的理解，而且为解释非线性条件下的超短光脉冲传播提供了有价值的工具。

引用次数: 0