Artigos de revistas: "Transportation Mathematical models"

1

Barceló, Jaume. "A survey of some mathematical programming models in transportation". Top 5, n.º 1 (junho de 1997): 1–40. http://dx.doi.org/10.1007/bf02568528.

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Wang, Yishan, Yushu Cui, Zihan Kong, Xingxin Liao e Weiran Wang. "Design of Public Transportation System Scheduling and Optimization in the Internet of Things (IoT) Environment". Advances in Engineering Technology Research 9, n.º 1 (25 de dezembro de 2023): 89. http://dx.doi.org/10.56028/aetr.9.1.89.2024.

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This study aims to explore the scheduling and optimization of public transportation systems in the Internet of Things (IoT) environment. By establishing mathematical models, this research analyzes the current state of public transportation systems, proposes scheduling and optimization strategies based on mathematical models, and validates the effectiveness of these strategies through case studies. The research findings indicate that mathematical models have significant potential in improving public transportation efficiency, reducing costs, promoting environmental sustainability, and enhancing passenger experiences. Future research directions include real-time data integration, the application of machine learning, multi-modal transportation integration, sustainable practices, and the development of user-centric solutions.

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Makhova, Larisa, Mark Haykin, Irina Glazkova e Olga Domnina. "Development of Mathematical Models for Trucks and Cargo". Infrastructures 8, n.º 2 (28 de janeiro de 2023): 17. http://dx.doi.org/10.3390/infrastructures8020017.

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International trade allows countries to expand their markets and access goods and services that otherwise may not have been domestically available. As a result of international trade, the market is more competitive. This ultimately results in more competitive pricing and brings a cheaper product home to the consumer. The development of mathematical models to optimize the delivery of goods using a limited number of trucks is an urgent task for researchers around the world. The research goal was to use a developed mathematical model that allows one to optimize the performance of transportation tasks based on the selected parameters, both in terms of a particular truck and a fleet of trucks in the Russian region. The parameters (function, condition, cost, time, and quality) were set and an algorithm for the process of matching a specific truck and cargo was developed as part of the unit transportation task. A mathematical model has been developed for performing multiple freight tasks and operating a fleet of trucks, which considering such factors as cost, time, quality, and reputation, allows one to find an acceptable solution for a specific transportation task. A mathematical model was developed that considers such factors as cost, time, quality, and reputation, allowing one to find an acceptable solution for a particular transportation task. The simulation was performed in MATLAB 2018. The parameters of the simulations were a population size of 300, a maximum number of iterations of 2000, and a probability of selection of 0.85. From the 30 runs, the optional value was chosen as the best solution. The developed mathematical models have been tested for solving single and multiple transport problems under truck fleet simulation conditions. The results of the work can be used to optimize the operation of truck fleets in the Russian Federation and other countries.

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4

Cao, Junfang. "Mathematical Model and Algorithm of Multi-Index Transportation Problem in the Background of Artificial Intelligence". Journal of Advanced Transportation 2022 (26 de abril de 2022): 1–11. http://dx.doi.org/10.1155/2022/3664105.

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The development of artificial intelligence has brought rapid changes to human life and brought great convenience to human activities. The development of various modes of transportation has also brought convenience to people’s travel and commodity transactions, but it has also added more issues that need to be carefully considered. Because of the diversification of transportation methods, transportation problems also arise many fields, such as air transportation, water transportation, and land transportation. The development of mathematical models and algorithms for transportation problems is also in full swing, and it is a major trend to introduce mathematical models and algorithms into the solution of transportation problems. This paper deals with the multi-index transportation problem by establishing a multi-index mathematical model and algorithm to find a scientific transportation method for the goods to be transported, so as to save the cost and time of transportation. Experiments show that the mathematical model established in this paper has high efficiency for solving the multi-index transportation problem. At the same time, the most suitable transportation method can also be selected for the transportation of goods, and the route planned by the mathematical model and algorithm can reduce the risk to 12.34%.

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Cao, Junfang. "Mathematical Model and Algorithm of Multi-Index Transportation Problem in the Background of Artificial Intelligence". Journal of Advanced Transportation 2022 (26 de abril de 2022): 1–11. http://dx.doi.org/10.1155/2022/3664105.

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The development of artificial intelligence has brought rapid changes to human life and brought great convenience to human activities. The development of various modes of transportation has also brought convenience to people’s travel and commodity transactions, but it has also added more issues that need to be carefully considered. Because of the diversification of transportation methods, transportation problems also arise many fields, such as air transportation, water transportation, and land transportation. The development of mathematical models and algorithms for transportation problems is also in full swing, and it is a major trend to introduce mathematical models and algorithms into the solution of transportation problems. This paper deals with the multi-index transportation problem by establishing a multi-index mathematical model and algorithm to find a scientific transportation method for the goods to be transported, so as to save the cost and time of transportation. Experiments show that the mathematical model established in this paper has high efficiency for solving the multi-index transportation problem. At the same time, the most suitable transportation method can also be selected for the transportation of goods, and the route planned by the mathematical model and algorithm can reduce the risk to 12.34%.

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Jacob, C., F. Charras, X. Trosseille, J. Hamon, M. Pajon e J. Y. Lecoz. "Mathematical models integral rating". International Journal of Crashworthiness 5, n.º 4 (janeiro de 2000): 417–32. http://dx.doi.org/10.1533/cras.2000.0152.

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Zuo, Li. "Study on Mathematical Model of Freight Transportation Logistic Control". Applied Mechanics and Materials 178-181 (maio de 2012): 2573–76. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.2573.

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Freight transportation activities in the present circumstances are closely related to a larger context of logistics decision-making, but logistic requirement is not relevant to all types of goods. Most existing freight transport demand models used for mode and route selection still focus only on the direct factors. This paper discusses the taxonomy of logistic and transport models, and the factors can be incorporated into freight transport demand models in order to improve the forecasting capability of the model.

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Zandieh, M., e S. Molla-Alizadeh-Zavardehi. "Synchronizing production and air transportation scheduling using mathematical programming models". Journal of Computational and Applied Mathematics 230, n.º 2 (agosto de 2009): 546–58. http://dx.doi.org/10.1016/j.cam.2008.12.022.

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Naderi, B., A. Ahmadi Javid e F. Jolai. "Permutation flowshops with transportation times: mathematical models and solution methods". International Journal of Advanced Manufacturing Technology 46, n.º 5-8 (2 de julho de 2009): 631–47. http://dx.doi.org/10.1007/s00170-009-2122-8.

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Patriksson, Michael. "Robust bi-level optimization models in transportation science". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 366, n.º 1872 (10 de março de 2008): 1989–2004. http://dx.doi.org/10.1098/rsta.2008.0007.

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Mathematical programmes with equilibrium constraints (MPECs) constitute important modelling tools for network flow problems, as they place ‘what-if’ analyses in a proper mathematical framework. We consider a class of stochastic MPEC traffic models that explicitly incorporate possible uncertainties in travel costs and demands. In stochastic programming terminology, we consider ‘here-and-now’ models where decisions must be made before observing the uncertain parameter values and the responses of the network users; the objective is to minimize the expectation of the upper-level objective function. Such a model could, for example, be used to derive a fixed toll pricing scheme that provides the best revenue for a given network over a time period, where variations in traffic conditions and demand elasticities are described by distributions of parameters in the travel time and demand functions. We present new results on the stability of globally optimal solutions to perturbations in the probability distribution, establishing the robustness of the model. We also discuss penalization and discretization algorithms, the latter enabling the use of standard MPEC algorithms, and provide many future research avenues.

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Minaev, V. A., V. M. Pizengolts, A. O. Faddeev, A. Y. Bystryakov, E. V. Savenkova e E. V. Kruglikova. "Modern information and mathematical models in construction industry". E3S Web of Conferences 116 (2019): 00051. http://dx.doi.org/10.1051/e3sconf/201911600051.

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Building information modelling (BIM) – new technology of construction object information maintenance. It allows specifying influence of changes and risks made in it (including geodynamic) at all stages of lifecycle. Objects include products, building equipment, technological platform, the building, engineering, transportation networks and systems of building communication. The model expands possibilities of innovative technologies implementation, allowing creating reasoned economic decisions.

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Wang, Haoqing, Wen Yi e Yannick Liu. "Optimal Route Design for Construction Waste Transportation Systems: Mathematical Models and Solution Algorithms". Mathematics 10, n.º 22 (18 de novembro de 2022): 4340. http://dx.doi.org/10.3390/math10224340.

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A huge amount of construction waste is generated in construction sites every day that needs to be transported by vehicle to disposal facilities for processing. Unlike in most typical transportation problems, once these vehicles are loaded with construction waste, they must travel directly to the disposal facility. Moreover, there are different types of construction waste that may require handling by different disposal facilities. In this paper, we develop a model and algorithm for identifying the optimal transportation routes specific to construction waste transportation. Our results can not only minimize the overall costs for both the logistics company and the contractor but also minimize the distance traveled, thus reducing urban traffic emissions.

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SUZUKI, YOSHINORI. "Finding the Proper Fleet-Downsizing Strategies for U.S. Agricultural Cooperatives: A Case of GROWMARK, Inc." Transportation Journal 48, n.º 2 (2009): 24–39. http://dx.doi.org/10.5325/transportationj.48.2.0024.

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Abstract U.S. agricultural cooperatives (coops) are facing the need to reduce their fleet sizes, and are interested in knowing the extent to which they should downsize their fleets. The standard fleet-sizing models (mathematical models) that determine the optimal fleet sizes may not be useful for coops, as these models do not consider the performance metric that is deemed most important by coops; i.e., the customer service quality. This article reports a case study in which we empirically examined the optimal fleet size of an agricultural coop by using customer service quality as the performance metric. We show the method of determining the fleet size and provide managerial implications regarding the extent to which coops may wish to downsize their fleets.

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Aleksejevs, Ruslans, Raufs Guseinovs, Alexander N. Medvedev e Sharif E. Guseynov. "Groupage Cargo Transportation Model". Transport and Telecommunication Journal 17, n.º 1 (1 de março de 2016): 60–72. http://dx.doi.org/10.1515/ttj-2016-0007.

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Abstract In this work we consider a specific problem of optimal planning of maritime transportation of multiproduct cargo by ships of one (corporate strategy) or several (partially corporate strategy) companies: the core of the problem consists of the existence of the network of intermediate seaports (i.e. transitional seaports), where for every ship arrived the cargo handling is done, and which are situated between the starting and the finishing seaports. In this work, there are mathematical models built from scratch in the form of multicriteria optimization problem; then the goal attainment method of Gembicki is used for reducing the built models to a one-criterion problem of linear programming.

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Hockicko, Peter, Peter Bury, Peter Sidor, Stanislav Jurecka e Igor Jamnicky. "Mathematical Models for Acoustic Spectra Simulation". Communications - Scientific letters of the University of Zilina 12, n.º 1 (31 de março de 2010): 44–49. http://dx.doi.org/10.26552/com.c.2010.1.44-49.

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Müller, Sven. "Advanced spatial analytics and management: models, methods and applications". Problems and Perspectives in Management 14, n.º 2 (11 de maio de 2016): 67–73. http://dx.doi.org/10.21511/ppm.14(2).2016.07.

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In this contribution, a concept of the integration of spatial predictive analytics and mathematical programs for spatial decision making – namely, advanced spatial analytics and management – is outlined. In particular, selected methods for spatial predictive analytics are discussed, including spatial econometrics and discrete choice analysis. Then, the integration of spatial predictive models in mathematical programs (prescriptive analytics) for facility location and districting is demonstrated. The paper includes illustrative applications which stem from health care, retail, marketing, logistics, and transportation. Based on the discussion, future research perspectives are developed

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Kyrychenko, Hanna, Yurii Statyvka, Oleh Strelko, Yulia Berdnychenko e KHalyna Nesterenko. "Assessment of Cargo Delivery Quality Using Fuzzy Set Apparatus". International Journal of Engineering & Technology 7, n.º 4.3 (15 de setembro de 2018): 262. http://dx.doi.org/10.14419/ijet.v7i4.3.19800.

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The influence of the existing operation conditions for the time of cargo transportation, i.e. ferrous metals to the port station, was investigated. It was proposed to carry out the management of cargo delivery on the basis of determining the values of cargo handling duration while implementing the stages of the schedule. It was proposed to carry out assessment of the delivery process, including transportation using the fuzzy set apparatus. To determine the quality of transportation, an ordered categorized scale of values of the duration of cargo's staying in certain conditions at delivery stages was proposed. The assessment of deviations at all the stages of transportation with the use of linguistic definitions of conditions allows quantifying such an indicator as the transportation quality. The characteristics of deviations during transportation are provided in the linguistic form to the dispatching unit for making a decision. The revealed regularities in deviations from the standard schedules of trains during delivery of cargos are an objective basis for taking into account them in the mathematical models of the forecast of time of cargo delivery at each of the defined stages of transportation. The data on the forecasted and actual transportations are accumulated in the existing information base, forming data files for assessing the quality of the transportation process, the adequacy of the mathematical model and correcting of the model in case of significant organizational or technical changes.

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Zhuraev, Mukhiddin, Jamshid Togaev e Zokirkhon Yusufkhonov. "Management of consumers needs for volume of transportation, taking into account the probable nature". E3S Web of Conferences 401 (2023): 01066. http://dx.doi.org/10.1051/e3sconf/202340101066.

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The article investigates the issue of continuous provision of consumers' needs for transportation, which is formed by chance. At the same time, the indicators of elementary random processes aimed at satisfying the needs of consumers in transportation were investigated, and corresponding mathematical models were formed for them; methodological properties and aspects of this approach were also substantiated. Based on the cost of transporting raw cotton materials from the Nuriston cotton station to the Nishan cotton ginnery, the reliability of the results of operational planning of transportation and transportation management is considered. Based on the mathematical models presented in the article, it becomes possible to continuously meet the production needs of an enterprise at any random cost of consumed and transported goods.

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Бурмистрова, Olga Burmistrova, Пильник e Yuliya Pilnik. "Development of methodology bases of the network mathematical models transportation and technological flows timber." Forestry Engineering Journal 6, n.º 2 (28 de abril de 2017): 63–68. http://dx.doi.org/10.12737/19955.

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The mathematical-mechanical modeling - is the study of complex transport systems (processes) through on-the structure and the research object model. Mathematical models allow a pre-selection of optimal solutions according to specific criteria. These scientifically based and are designed to help leaders in the development, validation and acceptance of efficient, high-quality management decisions in the forest complex. But it must be a pony-mother, that any solution obtained by calculating the mathematical model, optimal only for one or more criteria.

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Malovetskaya, Ekaterina V., e Anna K. Mozalevskaya. "Possibilities of application of ARIMA models in building forecast values of car-flows". T-Comm 17, n.º 1 (2023): 33–41. http://dx.doi.org/10.36724/2072-8735-2023-17-1-33-41.

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The current condition of developments in the field of estimating the unevenness of railway transportation in the field of solving the problems of efficiency of the organization of the transportation process with the use of landfill technologies is considered. Studying the problems of irregularities in the flow of cars, identifying the differences between unavoidable fluctuations from congestion or interruptions initiated by improper modes of movement with the need to eliminate, the creation of appropriate mechanisms to reduce unevenness can significantly optimize infrastructure use. The use of mathematical models of various kinds for formation of models of the forecast of change of car flows on railways is estimated. In particular, the method of time series allows you to build predictive models based on an array of data on car traffic. A comparative review of methods and means of forming forecast models of changes in car flows at the junctions of railways operating in a single technological space. The use of time series as a mathematical apparatus for constructing simulation models for forecasting wagon fluctuations and loading is estimated. Prospects for the use of simulation modeling as a tool for estimating the fluctuations of wagon flows at the junctions of railways with a single control center are considered. On the basis of the conducted analysis a number of directions of expansion of the existing methodological base of construction of simulation models of railway transportations is offered.

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Kuznetsov, V. H., e O. M. Lisohurskyi. "THE USE OF DYNAMIC MODELS OF CAR TRAFFIC VOLUME PROMOTION IN TECHNICAL REGULATION". Science and Transport Progress, n.º 20 (25 de fevereiro de 2008): 188–92. http://dx.doi.org/10.15802/stp2008/17390.

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Modern lines in the field of transport management are directed on transition from analytical systems of processing of information to the information-operating systems providing support of decision-making in management by transportations. New conditions of managing, on the one hand, and development of the automated systems of gathering and processing of information in transport industry, on the other hand, allows to reach essentially new level of planning the parameters of transport operation with development of new methodology of solution of the given problems. The creation of dynamic model of promotion of traffic volumes is one of the new methods that allows solving a number of operational problems.. In the paper the mathematical description of range of a network and dynamic model is given. The concept of individual transportation is presented, classification of dynamic models depending on the initial information is given. Mathematical study and algorithm of construction of dynamic models enables their applications for solution of wide range of problems on transport.

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Miyoba, Fines, Egbert Mujuni, Musa Ndiaye, Hastings M. Libati e Adnan M. Abu-Mahfouz. "Sustainable Rail/Road Unimodal Transportation of Bulk Cargo in Zambia: A Review of Algorithm-Based Optimization Techniques". Mathematics 12, n.º 2 (21 de janeiro de 2024): 348. http://dx.doi.org/10.3390/math12020348.

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Modern rail/road transportation systems are critical to global travel and commercial transportation. The improvement of transport systems that are needed for efficient cargo movements possesses further challenges. For instance, diesel-powered trucks and goods trains are widely used in long-haul unimodal transportation of heavy cargo in most landlocked and developing countries, a situation that leads to concerns of greenhouse gases (GHGs) such as carbon dioxide coming from diesel fuel combustion. In this context, it is critical to understand aspects such as the use of some parameters, variables and constraints in the formulation of mathematical models, optimization techniques and algorithms that directly contribute to sustainable transportation solutions. In seeking sustainable solutions to the bulk cargo long-haul transportation problems in Zambia, we conduct a systematic review of various transportation modes and related mathematical models, and optimization approaches. In this paper, we provide an updated survey of various transport models for bulk cargo and their associated optimized combinations. We identify key research challenges and notable issues to be considered for further studies in transport system optimization, especially when dealing with long-haul unimodal or single-mode heavy cargo movement in countries that are yet to implement intermodal and multimodal systems.

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Peng, Liangrong, e Liu Hong. "Recent Advances in Conservation–Dissipation Formalism for Irreversible Processes". Entropy 23, n.º 11 (31 de outubro de 2021): 1447. http://dx.doi.org/10.3390/e23111447.

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The main purpose of this review is to summarize the recent advances of the Conservation–Dissipation Formalism (CDF), a new way for constructing both thermodynamically compatible and mathematically stable and well-posed models for irreversible processes. The contents include but are not restricted to the CDF’s physical motivations, mathematical foundations, formulations of several classical models in mathematical physics from master equations and Fokker–Planck equations to Boltzmann equations and quasi-linear Maxwell equations, as well as novel applications in the fields of non-Fourier heat conduction, non-Newtonian viscoelastic fluids, wave propagation/transportation in geophysics and neural science, soft matter physics, etc. Connections with other popular theories in the field of non-equilibrium thermodynamics are examined too.

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Kolbachev, Evgeniy, Natalya Napkhonenko, Maryna Karayeva e Dmytro Maloshtan. "Development of specialized models of urban passenger transportation". SHS Web of Conferences 67 (2019): 03005. http://dx.doi.org/10.1051/shsconf/20196703005.

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Peculiarities of transport services for the transportation of passengers, which must be taken into account when creating logistics models for organizing and managing passenger flows, are considered. Need of cost reduction of time of passengers for transport service is proved. The conclusion is drawn on need of the effective transport system creation, for the purpose of observance of intervals of the movement of buses on routes. The possibility of use of architectural approximations classes for the solution of transport logistics problems is analysed. The methods used for solving transport problems where the most widespread is modeling and algorithmization of the determined task formulation strategy with use of a classical algorithm of mathematical programming are considered. The prospects of a meta-heuristic method use is a genetic algorithm for the solution of tasks of the control of city passenger transport adapted to objective conditions are proved. The main features of genetic algorithms consisting in an opportunity by optimization to use criterion function and to consider the necessary number of restrictions are defined. The structure of a chromosome which represents the coded option of the movement of the bus in real time depending on a road situation is received.

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Bogachev, Viktor, Petr Kurenkov, Evgeniya Chebotareva, Aleksandra Kravec e Taras Bogachev. "Computational Experiment in Optimization Modeling of Multimodal Cargo Transportation Process Based on Egalitarian Principles". Bulletin of scientific research results 2022, n.º 3 (22 de setembro de 2022): 151–62. http://dx.doi.org/10.20295/2223-9987-2022-3-151-162.

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Purpose: To build an optimization model of multimodal cargo transportations in a port-side transport and technological system with the participation of rail and sea kinds of transport based on egalitarian principles, the model allows manipulating the values of parameters characterizing a transportation process and taking into account interests of transportation process participants within the frames of being considered cost indicators. Methods: An algorithm has been developed for planning the shipment and delivery of cargo flows to port station address in view of routing, time and cost parameters of transportation process which under, cost optimal values of being transported cargo and complex time indicators of transportation process are provided. One of the limitations in the optimization task is the volume of a ship batch that’s expected at any port unloading stations. The built mathematical model is a multi-criteria and multi-extreme task of nonlinear stochastic integer programming. The research theoretical and economic basis is the synthesis of the classical concepts of utilitarian and egalitarian approaches in a welfare theory that makes it possible to build sounded theoretically and demanded in practice the optimization models of multimodal freight transportation railway component. Results: Developed in analytical computing system environment the optimization algorithm provides opportunities along with Pareto optimal transportation plans for to find plans embodying “just in time” logistic concept, so at these plans, it is also achieved the balance of interests of transportation considered participants. Practical importance: An approach is proposed for to study freight transportation organization on a railway landfill wherein transportations are pursued within the framework of multimodal port-side transport and technological system. The developed models and algorithms can be recommended for practical use during the formation and analysis of logistic supply chains with rail and sea transport kind participation.

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Mazūra, Mindaugas. "PREDICTION OF MAJOR TRENDS OF TRANSPORTATION DEVELOPMENT". TRANSPORT 17, n.º 2 (30 de abril de 2002): 57–59. http://dx.doi.org/10.3846/16483480.2002.10414012.

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The importance of forecasting the economic characteristics of transportation (i.e. the amount of freight and passengers carried, the turnover rate of freight and passengers, etc. in transportation as a whole and in particular areas using various transport facilities) is demonstrated. Methods for predicting the development of transportation based on multidimensional regression and correlation analysis and realizing mathematical models for finding linear and non-linear multidimensional regression equations as well as a mathematical model for choosing linear and non-linear regression equations, more accurately approximating the empirical data, are presented. The techniques aimed to obtain and apply the linear correlation coefficient and correlative relationship in determining the forecast accuracy is also given. The efficiency of methods, determining the linear correlation coefficient and correlative relationship, used in achieving higher accuracy of forecasts is shown.

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Bondarev, E. A., A. F. Voevodin, K. K. Argunova e I. I. Rozhin. "Equations of State in Mathematical Models of Natural Gas Production and Transportation Systems". Numerical Analysis and Applications 13, n.º 3 (julho de 2020): 258–61. http://dx.doi.org/10.1134/s1995423920030052.

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Matsukura, Hiroshi, Maytouch Udommahuntisuk, Hiroyuki Yamato e A. A. B. Dinariyana. "Estimation of CO2 reduction for Japanese domestic container transportation based on mathematical models". Journal of Marine Science and Technology 15, n.º 1 (14 de outubro de 2009): 34–43. http://dx.doi.org/10.1007/s00773-009-0069-y.

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Chung, Ki Ho, Chang Seong Ko, Jae Young Shin, Hark Hwang e Kap Hwan Kim. "Development of mathematical models for the container road transportation in Korean trucking industries". Computers & Industrial Engineering 53, n.º 2 (setembro de 2007): 252–62. http://dx.doi.org/10.1016/j.cie.2007.06.017.

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Jia, Guo-Ling, Rong-Guo Ma e Zhi-Hua Hu. "Review of Urban Transportation Network Design Problems Based on CiteSpace". Mathematical Problems in Engineering 2019 (20 de junho de 2019): 1–22. http://dx.doi.org/10.1155/2019/5735702.

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This paper provides a comprehensive review of urban transportation network design problems according to CiteSpace, including main problem classifications, mathematical models, and solution methods obtained from CiteSpace clusters. The review attempts to present the systematic picture of urban transportation network design and show the future directions of it.

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Olenkowicz-Trempała, Paulina, Aleksander Sobota, Jacek Chmielewski, Jan Kempa, Bertha Santos e Jorge Gonçalves. "Mobility in Transportation Surveys". IOP Conference Series: Materials Science and Engineering 1203, n.º 3 (1 de novembro de 2021): 032007. http://dx.doi.org/10.1088/1757-899x/1203/3/032007.

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Abstract An attempt to identify key factors impacting trip generation in different size cities is presented in this paper. Mobility is the fundamental factor in transport demand models, both for the present state and those for forecast scenarios. Moreover, research on inhabitants' mobility plays an important role in the process of urban and rural traffic modelling. It comes from the fact, regular transport surveys make it easier to determine factors impacting the number of trips taken by inhabitants in any selected study area, and to determine trends in these factors. Presentation of example results of mobility rate based on transportation surveys taken in various areas of Poland is the main goal of this paper. Results of analyses of selected macro-economic factors in transportation systems shaping are presented either. The trends in the number of inhabitants and their age composition, and motorization rates are those factors. They impact mobility ratios in the study area. Values of mobility ratio were developed based on the results of surveys which have been done in Poland till now, and on the authors' research. Mathematical regression models in estimating mobility ratio versus the selected independent factors are the results of this research either.

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Rusinov, Igor, Irina Gavrilova e Aleksandr Bersenev. "Cargo handling processes during containerized shipments: mathematical modeling, optimality criteria". MATEC Web of Conferences 239 (2018): 03011. http://dx.doi.org/10.1051/matecconf/201823903011.

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Containerized shipment is the most convenient and cost-saving method for transportation of goods. In this article the processes of containerized cargo handling based on a queuing model is formalized. Different cargo handling models are described, and the process modeling based on local mutual assistance is considered. Analytical models for process performance indicators in steady-state conditions are defined. Optimization issues in designing and operating transshipment terminals are identified and the ways of resolving these issues are offered. Analytical models of process performance indicators, helping to optimize cargo handling processes in special conditions, are defined.

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Samanta, Bablu, e Kumar Majumder. "Entropy based transportation model: A geometric programming approach". Yugoslav Journal of Operations Research 17, n.º 1 (2007): 43–54. http://dx.doi.org/10.2298/yjor0701043s.

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The entropy model has attached a good deal of attention in transportation analysis, urban and regional planning as well as in other areas. This paper shows the equivalence of entropy maximization models to geometric programs. To provide a better understanding of this entropy based transportation model they are analyzed by geometric programming. Dual mathematical programs and algorithms are also obtained and are supported by an illustrative example. .

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Díaz-Parra, Ocotlán, Jorge A. Ruiz-Vanoye, Beatriz Bernábe Loranca, Alejandro Fuentes-Penna e Ricardo A. Barrera-Cámara. "A Survey of Transportation Problems". Journal of Applied Mathematics 2014 (2014): 1–17. http://dx.doi.org/10.1155/2014/848129.

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This paper aims at being a guide to understand the different types of transportation problems by presenting a survey of mathematical models and algorithms used to solve different types of transportation modes (ship, plane, train, bus, truck, Motorcycle, Cars, and others) by air, water, space, cables, tubes, and road. Some problems are as follows: bus scheduling problem, delivery problem, combining truck trip problem, open vehicle routing problem, helicopter routing problem, truck loading problem, truck dispatching problem, truck routing problem, truck transportation problem, vehicle routing problem and variants, convoy routing problem, railroad blocking problem (RBP), inventory routing problem (IRP), air traffic flow management problem (TFMP), cash transportation vehicle routing problem, and so forth.

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Zhai, Ziyi. "A study of the application of linear programming to material transportation problems". Theoretical and Natural Science 9, n.º 1 (13 de novembro de 2023): 255–61. http://dx.doi.org/10.54254/2753-8818/9/20240769.

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With the quick development of the world logistics industry, the transportation cost of Chinese enterprises is still very high. There is still a lot of room for development compared with other developed countries. Reducing transportation costs, especially transportation costs, is one of the effective ways for enterprises to improve their income. Due to the rapid development of China's industry, the demand for various materials is increasing day by day. Therefore, China's material transportation is also getting more and more attention. Operations Research is a subject of establishing mathematical models to solve practical problems. It is very necessary to use the relevant theories of operations research to solve material transportation problems. By reading the related literature at home and abroad and analysing the characteristics of material transportation problems and the application of operations research in this field, it is found that the on-table operation method is unable to effectively solve the complex material transportation problems. In order to reduce the transportation cost of enterprises, by conducting theoretical and practical research on the material transportation problem in the field of logistics management, this paper aims to simulate and calculate it by establishing a mathematical model and using Lingo software.

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Aksentev, A. A. "Market-based pricing for road freight transportation". Vestnik Universiteta, n.º 11 (7 de janeiro de 2022): 94–102. http://dx.doi.org/10.26425/1816-4277-2021-11-94-102.

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The specifics of market pricing in the Russian road freight transport market by means of correlation and regression analysis have been studied. Statistically significant factors have been highlighted, and mathematical models have been constructed. The influence of fictitious variables (body type) that improve the quality of the calculated values has been noted. Regression equations useful for determining the average market value of tariffs have been drawn up, which, when compared to actual tariffs, may indicate the adequacy of freight transactions. The results of transport companies registered in the Krasnodar region have been considered. A differentiated approach has been justified, requiring enterprises to be divided into revenue growth groups in order to identify differences in profitability and its sustainability. The limitations and shortcomings of the mathematical model, which do not allow us to make an unambiguous conclusion about the unprofitable and low-margin nature of the industry, have been considered. Areas for future research have been suggested.

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Fomin, Oleksij, Juraj Gerlici, Alyona Lovskaya, Kateryna Kravchenko, Oleksii Burlutski e Vladimír Hauser. "Peculiarities of the mathematical modelling of dynamic loading on containers in flat wagons transportation". MATEC Web of Conferences 254 (2019): 02039. http://dx.doi.org/10.1051/matecconf/201925402039.

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The study deals with a shunting impact of 13-4085 wagon platform to a TK25 tank container. In order to define the loads acting on the container frame, 3D computer models of the 1СС size container is designed, both version – for liquid and dry material transport. The virtual model consider a longitudinal force from the wagon automatic coupling, vertical and horizontal forces from the wagon – containers interaction and also vertical forces of the container fittings. For checking adequacy of the created models, the container acceleration values was obtained in two scenarios. In the first case, when fittings are aligned relative to the fitting spots of a wagon, thus without possibility of relative movement. In the second case, movement within clearance of fitting spots is possible. Mathematical models of dynamic loads on these structures were solved by MathCad. Differential equations were solved by the Runge – Kutta method. Adequacy of the created models was checked with an F-test. On the basis of conducted calculation can be conclude that the hypothesis on the adequacy of the models was not rejected.

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Zhuravleva, Natalia, e Liana Chechenova. "Analytical model of reliability of the freight rail transportation forecasting system". BIO Web of Conferences 84 (2024): 05046. http://dx.doi.org/10.1051/bioconf/20248405046.

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The purpose of the study: to develop an analytical model of the reliability of the freight transportation forecasting system by railway transport. Methods: economic and mathematical methods and models of transportation forecasting adapted to the peculiarities of railway freight transportation –models based on “Bottom/Top” approaches, methods of predictive adjustment by types of cargo, methods of scenario forecasting. Results: an analytical model of the reliability of the freight rail transportation forecasting system has been developed, the distinctive feature of which is the integration of cargo transportation evaluation indicators, characteristics of scenario methods and parameters of the forecasting process, a forecast has been formed for the volume and structure of freight traffic following through the Oktyabrskaya railway landfill for the future up to 2030 in the category of main types of cargo.

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Zhuravleva, Natalia, e Liana Chechenova. "Analytical model of reliability of the freight rail transportation forecasting system". E3S Web of Conferences 460 (2023): 06043. http://dx.doi.org/10.1051/e3sconf/202346006043.

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The purpose of the study: to develop an analytical model of the reliability of the freight transportation forecasting system by railway transport. Methods: economic and mathematical methods and models of transportation forecasting adapted to the peculiarities of railway freight transportation – models based on “Bottom/Top” approaches, methods of predictive adjustment by types of cargo, methods of scenario forecasting. Results: an analytical model of the reliability of the freight rail transportation forecasting system has been developed, the distinctive feature of which is the integration of cargo transportation evaluation indicators, characteristics of scenario methods and parameters of the forecasting process, a forecast has been formed for the volume and structure of freight traffic following through the Oktyabrskaya railway landfill for the future up to 2030 in the category of main types of cargo.

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Stetsyuk, P., O. Lykhovyd e A. Suprun. "On Linear and Quadratic Two-Stage Transportation Problem". Cybernetics and Computer Technologies, n.º 4 (31 de dezembro de 2020): 5–14. http://dx.doi.org/10.34229/2707-451x.20.4.1.

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Introduction. When formulating the classical two-stage transportation problem, it is assumed that the product is transported from suppliers to consumers through intermediate points. Intermediary firms and various kinds of storage facilities (warehouses) can act as intermediate points. The article discusses two mathematical models for two-stage transportation problem (linear programming problem and quadratic programming problem) and a fairly universal way to solve them using modern software. It uses the description of the problem in the modeling language AMPL (A Mathematical Programming Language) and depends on which of the known programs is chosen to solve the problem of linear or quadratic programming. The purpose of the article is to propose the use of AMPL code for solving a linear programming two-stage transportation problem using modern software for linear programming problems, to formulate a mathematical model of a quadratic programming two-stage transportation problem and to investigate its properties. Results. The properties of two variants of a two-stage transportation problem are described: a linear programming problem and a quadratic programming problem. An AMPL code for solving a linear programming two-stage transportation problem using modern software for linear programming problems is given. The results of the calculation using Gurobi program for a linear programming two-stage transportation problem, which has many solutions, are presented and analyzed. A quadratic programming two-stage transportation problem was formulated and conditions were found under which it has unique solution. Conclusions. The developed AMPL-code for a linear programming two-stage transportation problem and its modification for a quadratic programming two-stage transportation problem can be used to solve various logistics transportation problems using modern software for solving mathematical programming problems. The developed AMPL code can be easily adapted to take into account the lower and upper bounds for the quantity of products transported from suppliers to intermediate points and from intermediate points to consumers. Keywords: transportation problem, linear programming problem, AMPL modeling language, Gurobi program, quadratic programming problem.

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Чермошенцева, А. А., e А. Н. Шулюпин. "Development of mathematical models for calculating parameters during transportation of a steam-water mixture". Вестник КРАУНЦ. Физико-математические науки, n.º 3 (22 de novembro de 2021): 94–109. http://dx.doi.org/10.26117/2079-6641-2021-36-3-94-109.

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В практике освоения геотермальных месторождений возникает необходимость нахождение взаимосвязи между параметрами потока. При транспортировке пароводяной смеси требуется определение условий, обеспечивающих стабильную работу трубопровода. На отечественных объектах геотермальной энергетики гидравлический расчет трубопроводов пароводяной смеси проводился с использованием компьютерной программы MODEL, разработанной авторами данной работы. Новые вызовы и появление теории устойчивости привели к созданию математической модели SWIP (Steam-Water Inclining Pipeline). В данной статье представлены этапы разработки авторами новой модели, отвечающей современным требованиям In the practice of developing geothermal fields, there is a need to find the dependence between the flow parameters. When transporting a steam-water mixture, it is necessary to determine the conditions that ensure the stability in the pipeline. At domestic geothermal energy, the hydraulic calculation of steam-water mixture pipelines was carried out using the computer program MODEL created by the authors of this work. New challenges and the emergence of the theory of stability led to the creation of a mathematical model SWIP (Stream-Water Inclining Pipeline). This article presents the stages of creating a new model by the authors that meets modern requirements.

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Bondarev, E. A., A. F. Voevodin, K. K. Argunova e I. I. Rozhin. "Choosing an equation of state in mathematical models of pipeline transportation of natural gases". Numerical Analysis and Applications 10, n.º 3 (julho de 2017): 198–206. http://dx.doi.org/10.1134/s1995423917030028.

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Göçmen, Elifcan, e Rızvan Erol. "Transportation problems for intermodal networks: Mathematical models, exact and heuristic algorithms, and machine learning". Expert Systems with Applications 135 (novembro de 2019): 374–87. http://dx.doi.org/10.1016/j.eswa.2019.06.023.

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Tukimun. "Traffic Stream Models on Road Section in Samarinda City (Case Study on AW. Syahranie Street)". International Journal of Advanced Technology and Social Sciences 2, n.º 1 (25 de janeiro de 2024): 11–20. http://dx.doi.org/10.59890/ijatss.v2i1.1149.

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The interaction of loads in the transportation system is called traffic flow. Traffic flow interactions are used in transportation facility planning, design, and operation. This quantitative study focuses on Jalan Abdul Wahab Syahranie in Samarinda City. It employs the Greenshield method, which analyzes numerical data generated by the linear equation method, to find a mathematical relationship between vehicle speed and density, volume and density, and volume and velocity. According to the analysis findings, the higher the vehicle volume, the slower the vehicle speed, and the higher the density value

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Mazūra, Mindaugas, e Olga Fadina. "THE RELIABILITY OF FORECASTS IN TRANSPORTATION". TRANSPORT 17, n.º 6 (31 de dezembro de 2002): 219–22. http://dx.doi.org/10.3846/16483840.2002.10414046.

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Major problems of forecasting the economic characteristics of transportation (i.e. the amount of freight and passengers carried, the turnover rate of freight and passengers, etc. in transportation as a whole and in particular areas using various transport facilities) are demonstrated. Methods for predicting the development of transportation based on multidimensional regression and correlation analysis and realizing mathematical models for choosing linear and nonlinear regression equations, more accurately approximating the empirical data, are presented. The research conducted has demonstrated that the most reliable forecasts may be made when the methods of choosing the proper non-linear regression equation described in Section 2 of the present paper are used.

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Ghorbani, Amir, Vahid Ghorbani, Morteza Nazari-Heris e Somayeh Asadi. "Data Assimilation for Agent-Based Models". Mathematics 11, n.º 20 (15 de outubro de 2023): 4296. http://dx.doi.org/10.3390/math11204296.

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This article presents a comprehensive review of the existing literature on the topic of data assimilation for agent-based models, with a specific emphasis on pedestrians and passengers within the context of transportation systems. This work highlights a plethora of advanced techniques that may have not been previously employed for online pedestrian simulation, and may therefore offer significant value to readers in this domain. Notably, these methods often necessitate a sophisticated understanding of mathematical principles such as linear algebra, probability theory, singular value decomposition, optimization, machine learning, and compressed sensing. Despite this complexity, this article strives to provide a nuanced explanation of these mathematical underpinnings. It is important to acknowledge that the subject matter under study is still in its nascent stages, and as such, it is highly probable that new techniques will emerge in the coming years. One potential avenue for future exploration involves the integration of machine learning with Agent-based Data Assimilation (ABDA, i.e., data assimilation methods used for agent-based models) methods.

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Melnyk, Oleksiy, Oleg Onishchenko, Svitlana Onyshchenko, Andrii Voloshyn, Yevgen Kalinichenko, Olena Rossomakha, Galyna Naleva e Oleh Rossomakha. "Autonomous Ships Concept and Mathematical Models Application in their Steering Process Control". TransNav, the International Journal on Marine Navigation and Safety of Sea Transportation 16, n.º 3 (2022): 553–51. http://dx.doi.org/10.12716/1001.16.03.18.

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Kurganov, V. M., M. V. Gryaznov e K. A. Davydov. "CITY-FORMING ENTERPRISES: RELIABILITY AND REDUCED COSTS OF THE PASSENGERS’ TRANSPORTATION". Russian Automobile and Highway Industry Journal 17, n.º 1 (5 de março de 2020): 98–109. http://dx.doi.org/10.26518/2071-7296-2020-17-1-98-109.

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Introduction. The paper substantiates the relevance of reducing costs for regular passenger traffic and increasing their reliability in relation to cities with city-forming enterprises. The organizational and technological specificity of the regular route network of urban transport in such cities is disclosed. The authors propose a method for organizing regular transportation routes based on a rational combination of basic routes that require boarding and disembarking passengers only at stopping points and backup routes with boarding and disembarking passengers in any place not prohibited by the rules of road traffic. The authors demonstrate route network optimization of the regular passenger transportation using the proposed economic and mathematical model and taking into account the costs of forming the infrastructure for organizing traffic on backup routes, operating costs of transportation, as well as the cost of eliminating failures in urban transport. The developed mathematical model for assessing the reliability of regular passenger transportation differs from the well-known models, which take into account the availability of backup routes in the regular route network. The research proves the practical implementation of the proposed recommendations by the example of public transport routes in Magnitogorsk.Materials and methods. The authors used the analysis of scientific and regulatory literature; economic and mathematical modeling of transport processes; methods for calculating the reliability of technical and transport systems; the statistical, technical and economic system analysis.Results. As a result, the authors revealed the optimization of the economic and mathematical model of the regular passenger transportation in cities with city-forming enterprises and a mathematical model for assessing the reliability of regular passenger transportation. Moreover, the paper presented practical recommendations on the organization of reserve routes for regular passenger transport on the example of Magnitogorsk.Discussion and conclusions. By the implementation of theoretical principles, mathematical models and recommendations developed in the course of the research, the authors show the effect of implementation and the possibility to obtain new scientific results. Moreover, the authors demonstrate the formation of an additional volume of traffic by 178 thousand passengers a year, an increase in the speed of communication by 7 km per hour, a decrease in the cost of transporting one passenger by 7% and an increase in reliability by 1.14.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

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Prytula, N., O. Gryniv e V. Dmytruk. "Simulation of nonstationary regimes of gas transmission systems operation". Mathematical Modeling and Computing 1, n.º 2 (2014): 224–33. http://dx.doi.org/10.23939/mmc2014.02.224.

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A mathematical model of the gas transmission system is studied in this article. Models of gas flows in the main technological objects that are involved in the transportation of gas are represented. The structure of the system is represented in terms of graph theory. Adaptive algorithm of the gas transportation system model implementation is constructed and real-world examples of its work are presented in this paper.

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Zolkiewski, Sławomir, e Leszek Dziczkowski. "Mathematical Model of the Damped Variable Cross Section Beam in Transportation". Advanced Materials Research 837 (novembro de 2013): 517–22. http://dx.doi.org/10.4028/www.scientific.net/amr.837.517.

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The paper concerns the problem of vibrations of beamlike system with variable cross section. The beam is treated as the movable system in transportation. The considered problem focuses on modelling and dynamic analysis of geometrically nonlinear beam systems in rotational motion within the context of damping. The major scientific purpose of the paper is to elaborate the mathematical model of such a system. Additionally, the main motion impact on the local vibrations due to the mathematical sense is determined. Moreover, it is necessary to remember the interactions between damping forces of the above mentioned mechanisms and the transportation effect. The main motion of the system is treated as transportation, whereas the vibrations of the system are treated as relative motion. There are two types of systems considered: simple vibrating longitudinally and simple vibrating transversally in the plane transportation. The most interesting elements of the analysis determine the dynamic state of the system and present the mutual coupling of vibration amplitudes, natural frequency, and transportation velocity. Analysis of systems moving with low velocities or vibrating only locally treats the systems as already known models in literature. There are many scientific articles where the forms of vibrations of these systems have been described. Due to the obtained results it will be possible to confront mathematical models with the known stationary and non-stationary systems. As regards complex and simple systems running at high speed, the resonance phenomenon can be noticed, and depending on the amplitude and frequency of vibrations, we consider the following cases: when the amplitude reaches theoretical infinity leading in practice to permanent damage of the mechanism or when the amplitude of vibration reaches a certain speed which can cause the decrease of durability of the whole system. The adequate practical usage of the above mentioned researches is justified by its wide range of applications. In the majority of technical cases, further analysis of the systems is considered to be far too much simplified when we ignore the elements of flexibility, damping, or the nonlinear geometry of the beam. All the mentioned influences are presented in the derived mathematical model in form of equations of motion.

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