{"title":"Data-driven flocking behavior of multi-agent systems under uncertain environments","authors":"Shuaiming Yan , Lei Shi , Panpan Zhu , Yi Zhou","doi":"10.1016/j.apm.2025.116449","DOIUrl":"10.1016/j.apm.2025.116449","url":null,"abstract":"<div><div>In numerous practical application scenarios, the collaborative control tasks of multi-agent systems are challenged by the fact that the dynamic characteristics and environmental conditions of agents (such as robots, drones, and autonomous vehicles, etc.) are often unknown. In this paper, an approach based on data-driven learning control barrier functions is proposed to investigate the flocking control issue of multi-agent systems with unknown dynamics under uncertain environments. The verification of the flocking behavior in multi-agent systems is facilitated by flocking error system, upon which a data-driven flocking controller employing pseudo partial derivatives is constructed. Secondly, a data-driven learning control barrier functions scheme based on the idea of Gaussian process is established for multi-agent systems under uncertain environment, which can ensure the safety of agents and eliminate the dependence of traditional control barrier functions method on the system model. Moreover, two zeroing control barrier functions are provided to ensure the safety and low uncertainty of the agents, respectively, so as to achieve system convergence. Finally, the effectiveness of theoretical results is verified through numerical simulation and experiments.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116449"},"PeriodicalIF":4.4,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159574","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":"Towards interval analysis of large-scale uncertainty in spatially varied interval field","authors":"Yi Wu , Zi-Yang Wang , Han Hu , Bo Liu","doi":"10.1016/j.apm.2025.116453","DOIUrl":"10.1016/j.apm.2025.116453","url":null,"abstract":"<div><div>In this work, we investigate the large-scale interval analysis for structures with spatially varied interval uncertainty. Our motivations come from the fact that sample data of uncertainties in practical engineering problems are often limited, and the lack of an interval analysis approach for large-scale uncertain-but-bounded field problems. To quantify uncertain material properties, geometries, and external loads that may vary spatially, we employ the B-spline Interval Field Decomposition (BIFD) method to reduce the complexity and dimensionality of uncertainty modeling. Unlike the available method, we introduce the Chebyshev polynomials of the first kind to approximate the original function with interval fields, thereby establishing an interval envelope function with interval parameters that is suitable for large-scale uncertainty problems. We then suggest utilizing an optimization-based approach to find combinations that make the approximate function reach extreme values within a given interval, thereby determining the boundaries of the above interval envelope. Finally, the Chebyshev Interval Polynomials Approximation (CIPA) framework is summarized and extended to jointly apply the Finite Element Method (FEM). Several numerical examples are presented to illustrate the effectiveness of the proposed approach, in which the uncertain material properties, geometry and loading are investigated. Compared with the conventional Interval Perturbation Analysis (IPA) and Monte Carlo Simulation (MCS), the suggested approach shows good potential in balancing the accuracy and efficiency of uncertainty propagation analysis, especially for large-scale uncertainties. This work also reveals that a midpoint offset phenomenon of the IPA when dealing with large-scale uncertainties is one of the reasons for its inaccuracy in interval analysis.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116453"},"PeriodicalIF":4.4,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119742","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}
Juan Camilo Molina-Villegas , Carlos Alberto Vega-Posada
{"title":"The Green’s functions differential transform element method: A new semi-analytical approach for the analysis of framed structures","authors":"Juan Camilo Molina-Villegas , Carlos Alberto Vega-Posada","doi":"10.1016/j.apm.2025.116451","DOIUrl":"10.1016/j.apm.2025.116451","url":null,"abstract":"<div><div>This paper presents the Green’s Functions Differential Transform Element Method (GFDTEM), a novel semi-analytical technique for analyzing linearly elastic framed structures subjected to arbitrary loads. As a powerful mesh reduction strategy, the GFDTEM uniquely integrates fundamental principles from the Finite Element Method (FEM), the Differential Transform Method (DTM), and the Green’s Functions Stiffness Method (GFSM). This synergistic combination yields a highly efficient and accurate modeling approach for complex structural systems. The method discretizes the structure into elements connected at nodes, following the FEM scheme, and characterizes each element by means of stiffness matrices, shape functions, and fixed-end forces. Within each element, the local response is systematically approximated by high-order polynomials derived via the DTM, while the challenging treatment of arbitrary loads is elegantly accomplished analytically using Green’s functions, a hallmark of its semi-analytical power. A defining feature of the GFDTEM is that its formulation relies solely on the solution of the homogeneous form of the governing differential equations -namely, the shape functions and stiffness matrix coefficients- leading to a compact, general and streamlined representation. Its versatility, efficiency and FEM-based formulation allows the GFDTEM to be seamlessly embedded within incremental-iterative linearisation schemes, granting considerable potential for extension to geometrically and materially nonlinear problems. The effectiveness and accuracy afforded by the GFDTEM are validated with illustrative examples for axially non-uniform rods, Euler-Bernoulli beams and frames.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116451"},"PeriodicalIF":4.4,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159575","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}
Yun Zhao , Dandan Liu , Daosheng Ling , Chaowei Wang , Zhanglong Chen , Changnv Zeng
{"title":"Theoretical analysis on soil deformation and pore pressure subjected to shield tunneling in unsaturated soil","authors":"Yun Zhao , Dandan Liu , Daosheng Ling , Chaowei Wang , Zhanglong Chen , Changnv Zeng","doi":"10.1016/j.apm.2025.116448","DOIUrl":"10.1016/j.apm.2025.116448","url":null,"abstract":"<div><div>The precise forecasting of soil displacement and pore pressure resulting from shield tunneling is crucial for evaluating construction quality and impacts on neighboring structures. Current research rarely accounts for soil unsaturation. This paper introduces an analytical initial-solution, distinct from the Mindlin solution, and a modified three-dimensional displacement solution to predict soil displacement and pore pressure due to work load and ground loss. Based on continuum mechanics, three-dimensional consolidation equations of unsaturated soil are established firstly. By assuming no volume change at the initial time, the initial solution for the half-space to a buried concentrated force is derived using the Hankel integral transform method. Thereafter, the displacement and pore pressure caused by work load are computed through the superposition method. The accuracy of the proposed solution is confirmed by comparing analytical findings with three field results and the Mindlin solution. The analysis indicates that as soil saturation increases, the displacement shows a decrease trend while pore water pressure initially increases then decreases. Compared to saturated condition, displacement and pore pressure can vary by 38% and 45%, respectively, under unsaturated conditions. Results based on the Mindlin solution underestimate shield tunneling displacement, potentially posing significant safety risks to shield construction and adjacent structures.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116448"},"PeriodicalIF":4.4,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158929","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}
Bo Dou , Zhengbo Luo , Tianchang Deng , Xiaoye Mao , Hu Ding
{"title":"A vibration-reduction pipe clamp with piecewise stiffness","authors":"Bo Dou , Zhengbo Luo , Tianchang Deng , Xiaoye Mao , Hu Ding","doi":"10.1016/j.apm.2025.116452","DOIUrl":"10.1016/j.apm.2025.116452","url":null,"abstract":"<div><div>Pipe clamps are used widely for constraining pipes with relatively large sizes in aircraft. However, traditional clamps have large linear restraint stiffness and unsatisfactory vibration control effect. A pipe clamp model with piecewise-linear stiffness is proposed for the first time to improve vibration reduction ability. The mathematical model for the vibration of an aircraft fluid-conveying pipe constrained by two novel piecewise clamps is established. The left end of this pipe is subjected to a harmonic displacement excitation. The governing equations of the forced and natural vibrations are discretized by the Galerkin truncation method. The dynamics responses of the pipe are numerically calculated via the Runge-Kutta method and verified via the harmonic balance method. The effects of the parameters of the piecewise clamp on the dynamics responses of the pipe are explored. The vibration control performance of the piecewise clamp is compared with that of the traditional clamp and the linear clamp without piecewise stiffness. The new clamp with piecewise stiffness has a significantly higher vibration attenuation efficiency than the other two kinds of clamps. The piecewise stiffness characteristics of the novel clamp enable it to effectively control pipe vibrations even under strong excitation. At last, the forced vibration experiments are conducted. The superior vibration attenuation ability of the piecewise clamp is testified. This research can guide the design and mathematical modelling of the new pipe clamp with piecewise stiffness. It also provides novel insights into nonlinear vibration control for pipes.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116452"},"PeriodicalIF":4.4,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145103920","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":"Modeling and solving production planning in a two-factories symbiotic network with uncertain demands","authors":"Ch. Chamani , E.-H. Aghezzaf , A. Khatab","doi":"10.1016/j.apm.2025.116443","DOIUrl":"10.1016/j.apm.2025.116443","url":null,"abstract":"<div><div>Industrial Symbiosis (IS) refers to an eco-collaboration between factories, where the waste (<em>i.e.,</em> byproduct) generated by one factory is repurposed as an alternative raw material for another. This study investigates the integrated production planning problem within a symbiotic network of two factories operating under uncertain demand in an IS setting. The problem is modeled as an integrated capacitated lot-sizing problem, for which two mathematical formulations are proposed: a natural formulation and a plant-location reformulation. To address uncertain demand with known probability distributions, a two-stage stochastic programming model is developed based on the plant-location reformulation and solved using the Sample Average Approximation (SAA) method. Subsequently, a distributionally robust optimization (DRO) model–with a polynomial number of constraints–is developed to handle demand characterized by unknown distributions with infinite support. Computational experiments demonstrate that, in terms of robustness and cost variability, DRO solutions consistently outperform those obtained via the SAA method. Although DRO yields more conservative plans than SAA, it offers enhanced robustness and reduced variability, with superior worst-case performance–particularly in complex scenarios arising from multi-modal distributions. From a practical perspective, cost segmentation reveals that DRO-based solutions significantly reduce cost variability by minimizing reliance on expensive outsourcing in extreme scenarios. Overall, the results show that symbiotic collaboration reduces network costs by eliminating disposal charges and lowering expenses for purchased raw materials. These findings highlight the potential of robust planning to enhance cost efficiency for industrial organizations engaged in IS and operating in volatile markets.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116443"},"PeriodicalIF":4.4,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222047","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}
Jiawen Hu , Min Li , Shirong Zhou , Xinze Lian , Yiguan Shi
{"title":"A Wiener process with generalized heterogeneity and volatility-rate dependence for degradation analysis","authors":"Jiawen Hu , Min Li , Shirong Zhou , Xinze Lian , Yiguan Shi","doi":"10.1016/j.apm.2025.116432","DOIUrl":"10.1016/j.apm.2025.116432","url":null,"abstract":"<div><div>Unit-to-unit variability is commonly observed in the degradation of a population due to unobservable factors, such as variations in raw materials, usage patterns, and other influences. In the literature, this heterogeneity in degradation rates or volatility is often treated as a random effect. However, in practice, degradation rate and volatility may be interdependent. This study develops a Wiener degradation model in which degradation volatility is modeled as a function of the degradation rate. Additionally, a generalized inverse Gaussian distribution is employed to describe unit-specific heterogeneity, effectively capturing potential skewness and heavy-tailed characteristics. We derive a generalized closed-form expression for the lifetime distribution of the proposed model, incorporating different combinations of time-scale transformation functions. A statistical inference scheme based on the expectation-maximization algorithm, along with an interval estimation strategy, is presented. The effectiveness and applicability of the proposed model and corresponding algorithm are validated through comprehensive numerical simulations and two real-world datasets.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116432"},"PeriodicalIF":4.4,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145103919","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}
Nafiu Hussaini , Abdullahi Ahmed Yusuf , Adamu Ishaku
{"title":"Mathematical assessment of co-dynamics of deformed wing virus variants A and B infections in honeybees","authors":"Nafiu Hussaini , Abdullahi Ahmed Yusuf , Adamu Ishaku","doi":"10.1016/j.apm.2025.116431","DOIUrl":"10.1016/j.apm.2025.116431","url":null,"abstract":"<div><div>This study presents a mathematical model to assess the co-dynamics of infections with Deformed Wing Virus (DWV) Variants A and B within a honeybee hive. The model is analyzed via submodels, DWV A only and DWV B only. Our qualitative analysis results demonstrate that the disease-free equilibrium of each submodel is locally asymptotically stable when the corresponding reproduction number is below one. In addition, the submodels exhibit backward bifurcation. A numerical simulation shows that breeding bees for resistance reduces the number of infected brood and adults. The simulation further suggests that enhancing the efficiency of breeding bees for hygienic and grooming behavior in bees could be an effective strategy for controlling the spread of both DWV variants and mite populations. The sensitivity analysis results show that the most important parameters that contribute to the generation of more DWV infections are the transmission rate of DWV-B, the rate of maturation to infected adult bees, and the egg-laying rate. Furthermore, the uncertainty analysis result highlights that focusing on interventions like breeding bees for resistance, hygienic, and grooming behavior could lead to a relatively lower reproduction number. Finally, the result obtained from cost-effectiveness analysis suggests that implementing all interventions concurrently (the universal strategy) is the most cost-effective when resources are available. Otherwise, breeding bees for hygiene and grooming behavior is the most cost-effective strategy. However, the choice of which strategy to implement depends on policymakers’ budget constraints.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116431"},"PeriodicalIF":4.4,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145103924","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":"Modeling of Love-type wave propagation in a fractional poro-viscoelastic layer over a viscoelastic-to-elastic half-space, induced by a Gaussian source","authors":"Subhajyoti Sarkar, Santimoy Kundu","doi":"10.1016/j.apm.2025.116441","DOIUrl":"10.1016/j.apm.2025.116441","url":null,"abstract":"<div><div>This study presents a mathematical model for the propagation of Love-type surface waves generated by a Gaussian distributed source in a poro-viscoelastic layer that lies above a viscoelastic-to-elastic half-space. The model incorporates memory-dependent fractional viscoelasticity using Riemann–Liouville derivatives to more accurately represent time-dependent mechanical behavior. The governing equations for wave motion are derived for both the layered and half-space media, taking into account poroelastic interactions and spatial variations in material properties. Using Fourier and Green’s function techniques, dispersion relations are derived and analyzed. Numerical simulations examine the influence of various parameters, including heterogeneity factors, fractional memory indices and the characteristics of the Gaussian source, on the dispersion characteristics of the Love-type waves. To extend these findings to structural implications, a single-degree-of-freedom oscillator model is employed and Monte Carlo simulations are carried out to compare oscillator responses excited by Gaussian versus point sources. The combined analysis of dispersion phenomenon and oscillator response highlights the dominant role of the fractional memory parameters of the top poro-viscoelastic layer in controlling the maximum amplitude and the vibration duration of the oscillator. By linking wave dispersion with oscillator dynamics, this framework bridges source–medium characterization and structural response, underscoring that explicit inclusion of fractional viscoelasticity is essential for accurate seismic hazard modeling and reliable estimation of structural demands.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116441"},"PeriodicalIF":4.4,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107855","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":"Nonlocal micropolar elastic Rayleigh waves","authors":"Nguyen Thi Kieu , Pham Chi Vinh","doi":"10.1016/j.apm.2025.116433","DOIUrl":"10.1016/j.apm.2025.116433","url":null,"abstract":"<div><div>The problem of Rayleigh waves propagating in nonlocal micropolar isotropic elastic half-spaces modeled by Eringen’s (integral) nonlocal micropolar elasticity theory has been investigated (Ultrasonics 73 (2017) 162–168). However, since the authors employed the non-equivalent differential nonlocal model and the Eringen method which does not satisfy the original equations of motion, the obtained solution is incorrect. In this paper, we reconsider this problem. The problem is reformulated based on the equivalent differential nonlocal micropolar elasticity model and its solution is found by a novel method introduced recently (Proc. R. Soc. A 480 (2293) 20230814, 2024) which satisfies the original equations of motion. The solution of the Rayleigh wave problem has been obtained including explicit expressions of displacements, microrotation, nonlocal stresses and couple stresses along with explicit dispersion equation. The paper also provides a well-posedness criterion of Eringen’s nonlocal micropolar elasticity theory for harmonic plane wave problems. From the well-posedness criterion, it implies that it is impossible for a Rayleigh wave to propagate in nonlocal micropolar elastic half-spaces characterized by the kernel <span><math><msub><mi>K</mi><mn>0</mn></msub></math></span> (the modified cylindrical Bessel function of the second kind of order zero).</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"151 ","pages":"Article 116433"},"PeriodicalIF":4.4,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119740","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}