Applied Mathematical Modelling最新文献

{"title":"Integrated motion control for autonomous vehicles operating under nonlinear disturbances","authors":"Siyuan Jia ,&nbsp;Minhao Liu ,&nbsp;Huiyuan Xiong ,&nbsp;Kuongkun Sio ,&nbsp;Zhineng Long ,&nbsp;Xiangwei Bu","doi":"10.1016/j.apm.2025.116264","DOIUrl":"10.1016/j.apm.2025.116264","url":null,"abstract":"<div><div>This paper focuses on the stability control problem of autonomous vehicles operating under nonlinear disturbances. A hierarchical control framework is proposed to achieve both robustness and fast convergence of tracking errors, ensuring the asymptotic stability of the closed-loop system. Specifically, an upper-layer velocity planner is designed to constrain the kinematic behavior of the vehicle and enhance state stability under strong external disturbances. In the lower-layer controller, a control framework based on the robust integral of sign error with a robust prescribed performance function is developed to eliminate the chattering effect of sliding mode control and guarantee the continuity of control inputs. The proposed robust prescribed performance function ensures rapid tracking error convergence while effectively suppressing overshoot. Furthermore, to handle the uncertainties in vehicle dynamics, a multilayer neural network disturbance estimator based on a minimal parameter learning approach is constructed, enabling real-time compensation of uncertainties within the control loop. The stability of the overall hierarchical control framework is rigorously proved using Lyapunov theory. Finally, extensive comparative experiments are carried out in a high-fidelity CarSim-Simulink co-simulation platform under two typical nonlinear disturbance scenarios. The results demonstrate that the proposed control scheme outperforms existing methods in terms of robustness while achieving superior steady-state performance.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116264"},"PeriodicalIF":4.4,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144489894","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":"Spherical indentation over multilayered gels","authors":"Ernian Pan ,&nbsp;Zhijie Jin ,&nbsp;Zhiqing Zhang ,&nbsp;Guozhan Xia ,&nbsp;Kaifu Liu","doi":"10.1016/j.apm.2025.116279","DOIUrl":"10.1016/j.apm.2025.116279","url":null,"abstract":"<div><div>Functionally multilayered/graded gels have been extensively developed and applied across various fields, particularly in biomedical and environmental engineering. In this paper, we present novel semi-analytical solutions for the time-dependent response of a rigid sphere on a multilayered anisotropic gel, a reduced Biot poroelastic material, with the indentation force determined by the time-varying penetration. We first eliminate the time variable by using the Laplace transform, and then combine the Fourier-Bessel series (FBS) system of vector functions with the dual-variable and position (DVP) method to derive the Green’s function in terms of ring load over the Biot poroelastic media. The time-domain solution is finally obtained by employing the integral least-square method and the inverse Laplace transform. The proposed method is first validated by comparing with existing solutions for a uniform gel under spherical indentation. Numerical analyses are then conducted to further demonstrate the influence of material anisotropy, permeability, layering, gradient index, and surface permeability condition on the indentation responses, e.g., the indentation force, effective stress, and pore pressure distributions. This advanced and novel semi-analytical solution provides a robust computational framework. It enables precise optimization of layering configurations for multilayered gels and even identification of optimal gradient factors for functionally graded distributions. As such, it serves as a fundamental model for the indentation characterization and material parameter inversion of kindred advanced soft materials.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116279"},"PeriodicalIF":4.4,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144515637","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":"State-space formulations to understand the nonlinear viscoelastic mechanical behavior of tricuspid valve chordae tendineae","authors":"Li-Wei Liu ,&nbsp;Yuan-Jyun Shih ,&nbsp;Chih-Ming Chao ,&nbsp;Michael J. Burkhart ,&nbsp;Colton J. Ross ,&nbsp;Chung-Hao Lee","doi":"10.1016/j.apm.2025.116262","DOIUrl":"10.1016/j.apm.2025.116262","url":null,"abstract":"<div><div>The state-space representation is an alternative description of a dynamical system to the input-output representation in systems theory. In this paper, we used the state-space representation to study the mechanical behavior of the tricuspid valve (TV) chordae tendineae. The TV chordae behave viscoelastic features under the loading; hence, we cast the generalized Kelvin model with an additional nonlinear spring into the state-space description to develop the solution under different loading conditions. With the aid of the state-space representation, the closed-form solution of the displacement response of TV tissue can be analytically obtained, for the case of force control. Taking into account the in-resistance of compression of biological soft tissue, the exact response to a non-negative sinusoidal cyclic force was <em>for the first time</em> derived. In contrast, under displacement input, the state-space representation resulted in a nonlinear dynamical system and made the analytical solution of the force response unreachable. Thus, we developed a numerical scheme to solve the corresponding force response under the state-space representation framework. Based on the analytical solution, we further demonstrated that the conventional dynamic mechanical analysis (DMA), which has been widely used in modeling <em>linear</em> viscoelastic materials, is not suitable for the identification of the nonlinear, viscoelastic mechanical features of the TV chordae.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"149 ","pages":"Article 116262"},"PeriodicalIF":4.4,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144515640","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":"Anti-plane waves in a layered cylindrical piezo-composite structure considering interface model","authors":"Xuan Wang,&nbsp;Feng Jin","doi":"10.1016/j.apm.2025.116275","DOIUrl":"10.1016/j.apm.2025.116275","url":null,"abstract":"<div><div>The interface model mainly includes interface effects and a spring model. The bond of surface acoustic wave sensors at the joint between a guide wave layer and a thicker substrate always undergoes the gigantic stress that may result in slipping at the interface. Furthermore, the interface stress and the interfacial imperfection are increasingly vital for analyzing the nanosensors. Thus, it is of significant importance for us to further explore the dynamic and electromechanical behaviors of SH waves in a layered cylindrical piezocomposite nanostructure with the interface model. Thus, this paper aims to gain fresh insight into how interface piezoelectricity and the interfacial imperfection simultaneously affect the physical attributes of the anti-plane wave in a composite structure consisting of a piezoelectric nanoshell and an elastic nanocylinder. To intuitively seek out the unique properties of anti-plane waves in a nanoscale cylindrical piezo-composite structure, the bulk waves’ velocity in the piezoelectric nanoshell is roughly determined by the governing equations. Moreover, the phase velocity equations of SH waves in a piezoelectric nanoshell covered on a thicker elastic cylinder are derived employing interface piezoelectricity and a spring model. The consequences show that the waves’ velocity increases with the enhancement of the piezoelectric shell thickness <em>h</em> to the elastic cylinder radius <em>r</em>_i. Besides, the waves’ velocity becomes slower or quicker resulting from an increasing interface density or interface modulus. The imperfect parameter slows down the waves. Additionally, the influences of interface piezoelectricity on the waves’ velocity, energy conversion efficiency, and mass loading sensitivity are further discussed individually. The results showcase that the optimal wavenumber, (<em>kh</em>)₁, corresponds to the maximum value of ∆<em>c</em>/<em>c</em>_SH unaffected by the interface modulus. The electric conditions play a decisive role in determining (<em>kh</em>)₁. As for the lower frequency, the electromechanical coupling efficiency benefits profoundly from the interface modulus. Excitingly, the optimal wavenumber (<em>kh</em>)₂ corresponds to the greatest electromechanical coupling efficiency, which tends to (<em>kh</em>)₁ when the interface modulus increases. Essentially, the mass loading sensitivity could be enhanced with the help of the interface modulus, as the sensory response to mass loading corresponds to the electrically shorted cases and is superior to that corresponding to the electrically opened cases. These results offer an exemplary platform for examining the performance of cylindrical SAW nanosensors with the consideration of interface piezoelectricity.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116275"},"PeriodicalIF":4.4,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144502160","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":"Nonlinear flutter suppression of marine risers exposed to internal and external annular flows by nonlinear energy sink","authors":"Yao Chen ,&nbsp;Xiao-Dong Yang ,&nbsp;Feng Liang","doi":"10.1016/j.apm.2025.116272","DOIUrl":"10.1016/j.apm.2025.116272","url":null,"abstract":"<div><div>This paper focuses on a class of marine riser supported by retaining clips and subjected to internal and external annular flows, and a nonlinear energy sink (NES) is strategically integrated to suppress its nonlinear flutter triggered by fluid-structure interaction (FSI) and geometric nonlinearity. The nonlinear governing equation is formulated using the Hamilton principle and discretized via the Galerkin method. Following stability analysis, the Runge-Kutta (R-K) time-domain simulation is conducted to explore the suppression mechanisms of nonlinear flutter. The results indicate flutter and buckling instabilities in the riser system, and further reveal three flutter suppression mechanisms of the NES, where the NES interacts with different riser modes via transient resonance capture (TRC), effectively mitigating nonlinear flutter. Complex modal coupling and energy transfer between the NES and the riser significantly affect the dynamic behaviour of the riser. The mass ratio, damping, stiffness, and installation position of the NES play a crucial role in determining the flutter suppression region, vibration amplitude, and critical flow velocity of the system. Moreover, the study examines the vibration reduction performance of the NES under various initial conditions, and further quantifies the parameter range ensuring strong robustness for nonlinear flutter suppression in the riser.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116272"},"PeriodicalIF":4.4,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514214","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":"Finite-time position tracking control for magnetic levitation systems with suspension air-gap constraints","authors":"Qixun Lan ,&nbsp;Pengwei Yue ,&nbsp;Na Liu ,&nbsp;Junwei Sun ,&nbsp;Sheng Liu","doi":"10.1016/j.apm.2025.116258","DOIUrl":"10.1016/j.apm.2025.116258","url":null,"abstract":"<div><div>For magnetic levitation systems, how to quickly and accurately regulate the levitating object position to a predefined space is of paramount significance. In this paper, two finite-time controllers with simple structure, high control accuracy and strong robustness are designed by using finite-time stability theory and homogeneous system theory. Both controllers can successfully solve the finite-time position tracking problem of magnetic levitation systems with suspension air-gap constraints. Specifically, by introducing a new fractional-type barrier Lyapunov function, a continuous finite-time state feedback controller is designed firstly. When only the system output is available, a continuous finite-time output feedback controller based on a non-smooth filter is constructed. The novelty of both control strategies proposed lies in the fact that they unify the finite-time position tracking control design for magnetic levitation systems with symmetric/asymmetric suspension air-gap constraints, without altering the structure of the controllers. Finally, the effectiveness of proposed control schemes is verified by simulation results.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116258"},"PeriodicalIF":4.4,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144489895","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":"General analytical calculation method of mapping relationship between foundation and rail deformation for high-speed railway","authors":"Marui Han ,&nbsp;Zhiping Zeng ,&nbsp;Xiangdong Huang ,&nbsp;Peicheng Li ,&nbsp;Weidong Wang ,&nbsp;Jun Luo ,&nbsp;Abdulmumin Ahmed Shuaibu","doi":"10.1016/j.apm.2025.116268","DOIUrl":"10.1016/j.apm.2025.116268","url":null,"abstract":"<div><div>The evolution of the service state of high-speed railway foundation will reflect the track geometry in varying degrees. To attain mapping relationship between foundation deformation and rail surface geometry, the composite-beam model of CRTS (China Railway Track System) II ballastless track was established first, displacement functions of rail, track slab, and base slab (support layer) were expanded into Fourier series with supplementary terms, and coefficient matrix of displacement functions of each structure layer was solved based on principle of stationary potential energy. Then the method was popularized to other types of ballastless track. The results show that the convergence solution to displacement functions of each track structure layer can be obtained by extracting the finite term of Fourier series. Heaviside function is introduced to describe the contact condition between base boards and foundations, and the amplitude and location of voids can be accurately acquired by fewer iterations, which are consistent with the finite element results. According to the described cases, the largest void of subgrade section occurs in the middle of the model with an amplitude of 7.57 mm and a wavelength of 7.85 m. The largest void of bridge section occurs at the end of the midspan beam with an amplitude of 0.62 mm and a wavelength of 3.28 m. The methods can uniformly analyze the mapping relationship between foundation deformation caused by diverse conditions such as uneven settlement of piers and subgrade, temperature effect of bridge structures and rail deflection of different types of ballastless track, and can significantly improve computational efficiency.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116268"},"PeriodicalIF":4.4,"publicationDate":"2025-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337756","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":"Retraction notice to “Syncretic K-shell algorithm for node importance identification and invulnerability evaluation of urban rail transit network” [Appl. Math. Modell. 120 (2023) 400419]","authors":"Yanhui Yin ,&nbsp;Wencheng Huang ,&nbsp;Anhao Xie ,&nbsp;Haoran Li ,&nbsp;Wenbing Gong ,&nbsp;Yin Zhang","doi":"10.1016/j.apm.2025.116261","DOIUrl":"10.1016/j.apm.2025.116261","url":null,"abstract":"<div><div>This article has been retracted: please see Elsevier policy on Article Correction, Retraction and Removal (<span><span>https://www.elsevier.com/about/policies-and-standards/article-withdrawal</span><svg><path></path></svg></span>).</div><div>This article has been retracted at the request of the Authors.</div><div>Post-publication the authors found a set of significant coding errors. This impacts correctness of some figures, tables, analysis and discussions. As a result there is a major and important change in the findings. The Editor-in-Chief assessed these issues and decided to retract the paper. Apologies to the readers for the inconvenience that this may have caused. Authors have been offered the opportunity to resubmit the corrected version of the article.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116261"},"PeriodicalIF":4.4,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337757","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 simple and accurate method for quantifying the area effect of unidirectional extreme ocean waves","authors":"Zhao Zhao ,&nbsp;Ying Min Low","doi":"10.1016/j.apm.2025.116267","DOIUrl":"10.1016/j.apm.2025.116267","url":null,"abstract":"<div><div>Prediction of extreme ocean waves is an important engineering problem. One application is the airgap design of an offshore structure, as waves impacting the deck can result in substantial damage. Most studies focus on the extreme wave prediction at one location, but the extreme wave over an area is higher than any single location. This phenomenon is known as the area effect, which is complex as it involves the correlations in space and time. This paper presents a study of the area effect, focusing on unidirectional waves. Criteria are developed for selecting the optimal spatial discretization when applying simulation methods to quantify the area effect. The physical mechanisms of area effect are elucidated based on new insights, and five key influencing parameters are identified. Finally, a simple method is developed for predicting the area effect factor, which allows the space-time extreme to be evaluated by multiplying this factor by the extreme at a point. The method involves only one fitting coefficient, and it can be easily implemented on a spreadsheet and incorporated into design codes. Comparison with numerical simulations show that the method is accurate and accounts for the complex effects of various parameters.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116267"},"PeriodicalIF":4.4,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337759","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":"Non-singular fixed-time sliding mode control for optimization of wind turbine power generation incorporating a type-2 fuzzy disturbance estimator","authors":"Ahmadreza Eskandari,&nbsp;Ramin Vatankhah","doi":"10.1016/j.apm.2025.116260","DOIUrl":"10.1016/j.apm.2025.116260","url":null,"abstract":"<div><div>It is crucial to operate a wind energy conversion system at the most efficient power point. In this context, this paper addresses the challenges involved in optimizing the power extraction capability of variable speed wind turbines. It proposes a novel adaptive terminal sliding mode control approach that incorporates a fuzzy observer. The wind turbine system experiences nonlinear behaviors, unknown actuator faults, parametric uncertainties, and time-varying external disturbances. In the first stage, a nonlinear disturbance observer is developed that utilizes an interval type-2 fuzzy system to estimate time-dependent, uncertain, and bounded system disturbances. Subsequently, an active fault-tolerant robust control structure is adopted based on an innovative continuous high-order non-singular terminal sliding mode control scheme, which uses the nonlinear disturbance observer to cope with unknown disturbances. Meanwhile, according to the stability analysis, the overall closed-loop system can achieve Lyapunov stability, and all the error signals will converge to small arbitrary compact sets within a fixed time. In the end, a hierarchical multi-objective particle swarm optimization is applied to obtain the optimal control settings. A comprehensive study is conducted to evaluate the performance of our control algorithm in comparison to different control strategies, considering the “Controls Advanced Research Turbine” wind turbine as a case study. The validation results obtained using the MATLAB/OpenFAST code demonstrate that the presented integrated controller offers improvements in terms of practical prescribed-time tracking stability, strong robustness, the elimination of the chattering phenomenon (typically associated with the conventional sliding mode control), and the eradication of the singularity problem in the control input (in contrast to the regular terminal sliding mode control).</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116260"},"PeriodicalIF":4.4,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337760","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}