Mathematical and Computer Modelling of Dynamical Systems最新文献

{"title":"Dynamic system optimal performances of shared autonomous and human vehicle system for heterogeneous travellers","authors":"Yao Li","doi":"10.1080/13873954.2020.1792509","DOIUrl":"https://doi.org/10.1080/13873954.2020.1792509","url":null,"abstract":"ABSTRACT Autonomous vehicles (AV) can solve vehicle relocation problems faced by traditional one-way vehicle-sharing systems. This paper explores the deterministic time-dependent system optimum of mixed shared AVs (SAV) and human vehicles (SHV) system to provide the benchmark for the situation of mixed vehicle flows. In such a system, the system planner determines vehicle-traveller assignment and optimal vehicle routing in transportation networks to serve predetermined travel demand of heterogeneous travellers. Due to large number of vehicles involved, travel time is considered endogenous with congestion. Using link transmission model (LTM) as a traffic flow model, the deterministic time-dependent system optimum is formulated as linear programming (LP) model to minimize the comprehensive cost including travellers’ travel time cost, waiting time cost and empty vehicle repositioning time cost. Numerical examples are conducted to show system performances and model effectiveness.","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1792509","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41397809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling and analysis of the nonlinear string-mass structure of the vibration absorber","authors":"L. Cvetićanin, M. Zukovic, Z. Rakaric, D. Cveticanin","doi":"10.1080/13873954.2020.1792510","DOIUrl":"https://doi.org/10.1080/13873954.2020.1792510","url":null,"abstract":"ABSTRACT In this paper a nonlinear string-mass structure of the vibration absorber is analyzed. This structure is convenient to be installed in vibration damping systems of high buildings for their protection in the case of earthquake. The considered string-mass structure contains a translator movable mass connected with two strings. Due to nonlinear geometric properties of the system the motion of the mass is described with a strong nonlinear second order differential equation. In the paper the approximate procedure for solving of the nonlinear equation of motion is developed. Based on the solution the influence of the string preloading force, slider mass and friction force on the vibration property of the string-mass system is investigated. It is concluded that variation of the preloading string force may be applied as a control parameter for vibration absorption and as the regulator of vibration decay time.","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1792510","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48417431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First principles versus artificial neural network modelling of a solar desalination system with experimental validation","authors":"A. Bagheri, N. Esfandiari, B. Honarvar, A. Azdarpour","doi":"10.1080/13873954.2020.1788609","DOIUrl":"https://doi.org/10.1080/13873954.2020.1788609","url":null,"abstract":"ABSTRACT The present study mainly focuses on enhancing the performance of solar still unit using solar energy through cylindrical parabolic collector and solar panels. A 300 W solar panel is used to heat saline water by thermal elements outside the solar still unit. Solar panels are cooled during the hot hours of the day; thus, reducing their temperature may lead to an increase in solar panel efficiency followed by an increase in the efficiency of the solar still unit. The maximum amount of freshwater used in the experiment was 2.132 kg/day. The experiments were modelled using ANNs. Based on neural network simulation results, there is a significant correlation between experimental data and neural network modelling. This paper compares experimental data with data obtained from mathematical modelling and ANNs. As a conclusion, the artificial neural network prediction has been more accurate than the simplified first principles model presented.","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1788609","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42217630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editor’s note","authors":"Wolfgang Kemmetmüller","doi":"10.1080/13873954.2020.1788808","DOIUrl":"https://doi.org/10.1080/13873954.2020.1788808","url":null,"abstract":"This is my first editorial since taking over as the editor-in-chief (EiC) of Mathematical and Computer Modelling of Dynamical Systems (MCMDS). First of all, I would like to express my deep appreciation to my predecessor Inge Troch, for her outstanding work for this journal. Not only did she act as the EiC of the journal for the last 25 years, she also was the key persons when the idea of initiating a journal dedicated to the mathematical modelling of dynamical systems came up. Moreover, I am very thankful for her support during the transition phase and I hope that I can count on her invaluable experience as EiC also in the future. MCMDS is a popular journal for authors who want to publish their high-quality scientific work related to theoretical concepts for the derivation, simulation, simplification, analysis, calibration, and validation of mathematical models for dynamical systems and their application to demanding real-world problems. This is evidenced by the large number of papers submitted to the journal. I am convinced that in view of the increasing computer power available and the development of new powerful algorithms the relevance of modelling and simulation of dynamical systems will become even more important in all disciplines. Thus, there is no doubt that the journal has the potential to further improve its position on the market in the next years. During my tenure as EiC of the journal, I want to make MCMDS one of the journals which is among the first choice for authors who want to publish high-quality scientific results on mathematical modelling. In order to achieve this goal, there are a few steps to be taken: The time to first decision and the time to final acceptance of a paper are important numbers from the authors’ point of view. Thus, it is my goal to keep these times as short as possible and I aim at having the first decision three month after submission at latest. Of course, it shall be understood that reducing these times does not mean that any compromises on the thorough peer-review process will be made. To broaden the field of expertise I plan to extend the editorial board. This will also help to balance the work load for the review process among more people. This should also help to decrease the time to first decision of a paper. Therefore, one of the first measures will be to form an editorial board which is constituted of both well-experienced researchers and researchers who are at an earlier stage of their scientific career. Special Issues have always been an important part of MCMDS. Therefore, in consultation with the editorial board we will motivate researchers or research groups to organize special issues dedicated to topical subjects in the field of mathematical modelling of dynamical systems. Many different aspects determine the quality and reputation of a journal. I am well aware that the impact factor is one of the most visible number. Thus, it is a goal to keep the impact factor of the journal at a reasonably ","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1788808","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43040602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid-Structure Port-Hamiltonian Model for Incompressible Flows in Tubes with Time Varying Geometries","authors":"Luis A. Mora, Ledoux. Yann, Héctor Ramírez, J. Yuz","doi":"10.1080/13873954.2020.1786841","DOIUrl":"https://doi.org/10.1080/13873954.2020.1786841","url":null,"abstract":"ABSTRACT A simple and scalable finite-dimensional model based on the port-Hamiltonian framework is proposed to describe the fluid–structure interaction in tubes with time-varying geometries. For this purpose, the moving tube wall is described by a set of mass-spring-damper systems while the fluid is considered as a one-dimensional incompressible flow described by the average momentum dynamics in a set of incompressible flow sections. To couple these flow sections small compressible volumes are defined to describe the pressure between two adjacent fluid sections. The fluid-structure coupling is done through a power-preserving interconnection between velocities and forces. The resultant model includes external inputs for the fluid and inputs for external forces over the mechanical part that can be used for control or interconnection purposes. Numerical examples show the accordance of this simplified model with finite-element models reported in the literature.","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1786841","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43355290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adieu and welcome","authors":"I. Troch","doi":"10.1080/13873954.2020.1788809","DOIUrl":"https://doi.org/10.1080/13873954.2020.1788809","url":null,"abstract":"During the 1980s, development of trains running safely without driver or of cars with ABS and ESC confronted many industries, especially automotive and aerospace industries, with the need for trustworthy simulation tools to improve their products quickly and at relatively low costs. Already in 1986 an IFAC symposium on Simulation in Control and in 1994 the first MATHMOD conference on Mathematical Modelling gathered each some 200 engineers and scientists to exchange ideas on how to establish trustworthy and easy-to-handle models for research and development. Moreover, very active working groups on simulation and modelling existed – primarily in Germany, the Benelux and in Scandinavia – with close relations to the industries of the respective countries. Therefore, it was not really astonishing for me when in 1993 a letter reached me from the Publishing House Swets & Zeitlinger telling that well-known experts from German Universities of Technology had made the suggestion to launch a new journal on Mathematical Modelling of Engineering Systems and, asking for my thoughts on that idea. After intensive discussions on the scope, the way of reviewing and the possibility of special issues, the idea became concrete. An Editorial Board was formed with S. MarsiliLibelli (Italy), P. C. Müller (Germany), D. J. Murray-Smith (UK) and R. E. Skelton (USA) as Associate Editors and with 25 further members from Austria, Belgium, Finland, France, Germany, Greece, Italy, Japan, Netherlands, Norway, Russia, Slowenia, Sweden and USA. After intensive discussions, the title of the journal could be fixed to be ‘Mathematical Modelling of Systems’ with the subtitle ‘Methods, Tools and Applications in Engineering and Related Sciences’. In June 1995 the first issue was published with papers dealing with modelling of an activated sludge process, of marine vehicles, of magnetic bearings, of a propeller-driven type aircraft and of electromagnetic losses in electric machinery with authors from Sweden, Norway, Switzerland, Germany and Belgium. These papers demonstrated quite well the original main focus of the journal. It was understood right from the beginning that all papers submitted to the journal must be peer-reviewed by at least two experts. At the beginning, this was not as easy as it is now. In the 1990s authors had to submit three paper copies via ordinary mail and these copies were sent in the same way to the reviewers – how comfortable can this be done now due to email and websites. There was also the agreement that papers dealing with an application must define not only the purpose of the model and the assumptions made in its development but that also model validation must be discussed carefully as models without validation, i.e. without comparison of model behaviour with real-world observation are of little use. Equally, comparison with already existing models must be provided whenever appropriate. MATHEMATICAL AND COMPUTER MODELLING OF DYNAMICAL SYSTEMS 2020, VOL. 26, ","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1788809","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47777508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiphysics finite element model for the computation of the electro-mechanical dynamics of a hybrid reluctance actuator","authors":"F. Cigarini, E. Csencsics, J. Schlarp, S. Ito, G. Schitter","doi":"10.1080/13873954.2020.1766509","DOIUrl":"https://doi.org/10.1080/13873954.2020.1766509","url":null,"abstract":"ABSTRACT In hybrid reluctance actuators, the achievable closed-loop system bandwidth is affected by the eddy currents and hysteresis in the ferromagnetic components and the mechanical resonance modes. Such effects must be accurately predicted to achieve high performance via feedback control. Therefore, a multiphysics electro-mechanical finite element model is proposed in this paper to compute the dynamics of a 2-DoF hybrid reluctance actuator. An electromagnetic simulation is adopted to compute the electromagnetic dynamics and the actuation torque, which is employed as input for a structural dynamic simulation computing the electro-mechanical frequency response function. For model validation, the simulated and measured frequency response plots are compared for two actuators with solid and laminated outer yoke, respectively. In both cases, the model accurately predicts the measurement results, with a maximum relative phase error of 1.7% between the first resonance frequency and 1 kHz and a relative error of 1.5% for the second resonance frequency..","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1766509","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48260987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cattaneo–Christov heat flux model for three-dimensional flow of a viscoelastic fluid on an exponentially stretching surface","authors":"Sehrish Malik, M. Ashraf, A. Jahangir","doi":"10.1080/13873954.2020.1777566","DOIUrl":"https://doi.org/10.1080/13873954.2020.1777566","url":null,"abstract":"ABSTRACT In this article, we explore the three-dimensional boundary-layer flow over an exponentially stretching surface in two parallel ways. Constitutive equations of a second-grade fluid are used. Instead of classical Fourier’s law, Cattaneo–Christov heat flux model is employed for the formulation of the energy equation. This model can predict the effects of thermal relaxation time on the boundary layer. The resulting partial differential equations are reduced into ordinary differential equations by similarity transformations. Homotopy Analysis Method (HAM) is employed to solve the non-linear problem. Physical impact of emerging parameters on the momentum and thermal boundary-layer thickness are studied.","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1777566","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47910941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Production and payment policies for an imperfect manufacturing system with discount cash flows analysis in fuzzy random environments","authors":"Puspita Mahata, G. C. Mahata","doi":"10.1080/13873954.2020.1771380","DOIUrl":"https://doi.org/10.1080/13873954.2020.1771380","url":null,"abstract":"ABSTRACT This paper considers an imperfect manufacturing system with credit policies in fuzzy random environments. The supplier simultaneously offers the retailer either a permissible delay in payments or a cash discount and retailer in turn provides its customer a permissible delay period. We used an alternate approach – discount cash flow analysis to establish an inventory problem. It is assumed that the elapsed time until the machine shifts from ‘in-control’ state to ‘out-of-control’ state is characterized as a fuzzy random variable. As a function of this parameter, the profit function is also a random fuzzy variable. Based on the credibility measure of fuzzy event, the model with fuzzy random elapsed time can be transformed into a crisp model . We establish several theoretical results to obtain the solution that provides the largest present value of all future cash flows. Finally, numerical example is given to illustrate the results and obtain some managerial insights.","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1771380","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43331010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Master-slave synchronization of neural networks with time-varying delays via the event-triggered control","authors":"Jun Zhou, Dongbing Tong, Qiaoyu Chen, Wuneng Zhou","doi":"10.1080/13873954.2020.1777567","DOIUrl":"https://doi.org/10.1080/13873954.2020.1777567","url":null,"abstract":"ABSTRACT This paper investigates the problem of master-slave synchronization of neural networks with time-varying delays via the event-triggered control (ETC). First, the proposed ETC can effectively reduce the total amount of data transmitted to the controller in the synchronization process and avoid communication channel congestion. Second, a master-slave synchronization of neural networks with time-varying delays is constructed, where delays within neural networks and the ETC are simultaneous existence. The controller is updated by the ETC. By the Lyapunov stability theory, some sufficient criteria are obtained to ensure master-slave synchronization of neural networks. Finally, a numerical example and a tunnel diode circuit example are used to verify the validity of results obtained.","PeriodicalId":49871,"journal":{"name":"Mathematical and Computer Modelling of Dynamical Systems","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2020-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/13873954.2020.1777567","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43575855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}