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Journal articles on the topic 'Transportation Management Mathematical models'
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1
Müller, Sven. "Advanced spatial analytics and management: models, methods and applications." Problems and Perspectives in Management 14, no. 2 (May 11, 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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Бурмистрова, Olga Burmistrova, Пильник, and Yuliya Pilnik. "Development of methodology bases of the network mathematical models transportation and technological flows timber." Forestry Engineering Journal 6, no. 2 (April 28, 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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Chen, Zhang, Liyuan Liu, Li Li, and Hui Li. "A Two-Stage Model for Project Optimization in Transportation Infrastructure Management System." Mathematical Problems in Engineering 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/914515.
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Mathematical optimization is very important for project decision in the Transportation Infrastructure Management System (TIMS). However, it has not been widely employed in TIMS due to poor performance of conventional optimization models in calculation speed and practical application. Therefore, it is necessary to improve the performance of optimization models. According to the process of decision-making in transportation management, a novel two-stage project optimization model, including budget allocation and project distribution, was proposed in this paper. Moreover, the methods of dynamic programming (DP) and genetic algorithm (GA) were applied to obtain an effective solution. The findings indicate that the new optimization method can provide a satisfactory and reasonable maintenance schedule for transportation infrastructure maintenance agencies whose routine management will benefit from the newly proposed model.
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Kyrychenko, Hanna, Yurii Statyvka, Oleh Strelko, Yulia Berdnychenko, and KHalyna Nesterenko. "Assessment of Cargo Delivery Quality Using Fuzzy Set Apparatus." International Journal of Engineering & Technology 7, no. 4.3 (September 15, 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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Samanta, Bablu, and Kumar Majumder. "Entropy based transportation model: A geometric programming approach." Yugoslav Journal of Operations Research 17, no. 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, and 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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Belokurov, Sergey, Vladimir Belokurov, Vladimir Zolnikov, Valery Lavlinsky, and Alexei Shtepa. "Models and Algorithms of Formation of Route Transport Network of a City." MATEC Web of Conferences 334 (2021): 01033. http://dx.doi.org/10.1051/matecconf/202133401033.
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Mathematical modeling in optimization problems of management of urban passenger transport in large cities is considered. The simulation of route of transportation network of large cities is determined by a relatively large number of their specific and individual properties which, in the process of their functioning, become more complex and interdependent ones. Algorithm of rational route network taking into account annular and circular routes in the schemes of organization of urban passenger transport is proposed.
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Amirov, Lochinbek F., Javlonbek S. Fayzullaev, Hasan Sh Rahimov, and Nargiza T. Shayusupova. "EMM of effective management of the integrated transportation and logistics system." E3S Web of Conferences 244 (2021): 08022. http://dx.doi.org/10.1051/e3sconf/202124408022.
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The authors chose the topic of an economic and mathematical model of effective management of an integrated transport and logical system, due to the relevance of the topic throughout the world and in all areas of activity. Effective integration is possible if it is based on the methodological principles of the concept of integrated logistics, when the economic interests of subjects and objects of the transport-logical system are coordinated while ensuring the implementation of the strategy and goals of the functioning of the system as a whole. The object of the research is the JSC “Uzbek Railways” of the Republic of Uzbekistan. The research priority is transport and logistics management. During the research, difficulties emerged that have created multivariance. The article presents modern methods of managing the transport and logistics system, the classification of modern methods of management concepts that make up the theoretical and methodological foundations of the integrated management of the transport and logistics system, the efficiency of delivery times for options A, B, C, D and the economic efficiency of managing the transport and logistics system. Transport and logistics models are considered in economics as a business concept, having calculated the best option, you can optimize the economic process. In the conclusion, recommendations are given on the use of a mathematical model, short-term and long-term strategies for effective management of the transport and logistics system are given.
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Raskin, Lev, Oksana Sira, and Viacheslav Karpenko. "TRANSPORTATION MANAGEMENT IN A DISTRIBUTED LOGISTIC CONSUMPTION SYSTEM UNDER UNCERTAINTY CONDITIONS." EUREKA: Physics and Engineering 4 (July 31, 2019): 82–90. http://dx.doi.org/10.21303/2461-4262.2019.00936.
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The problem of supply management in the supplier-to-consumer logistics transport system has been formed and solved. The novelty of the formulation of the problem consists in the integrated accounting of costs in the logistic system, which takes into account at the same time the cost of transporting products from suppliers to consumers, as well as the costs for each of the consumers to store the unsold product and losses due to possible shortages. The resulting optimization problem is no longer a standard linear programming problem. In addition, the work assumes that the solution of the problem should be sought taking into account the fact that the initial data of the problem are not deterministic. The analysis of traditional methods of describing the uncertainty of the source data. It is concluded that, given the rapidly changing conditions for the implementation of the delivery process in a distributed supplier-to-consumer system, it is advisable to move from a theoretical probability representation of the source data to their description in terms of fuzzy mathematics. At the same time, in particular, the fuzzy values of the demand for the delivered product for each consumer are determined by their membership functions. Distribution of supplies in the system is described by solving a mathematical programming problem with a nonlinear objective function and a set of linear constraints of the transport type. In forming the criterion, a technology is used to transform the membership functions of fuzzy parameters of the problem to its theoretical probabilistic counterparts – density distribution of demand values. The task is reduced to finding for each consumer the value of the ordered product, minimizing the average total cost of storing the unrealized product and losses from the deficit. The initial problem is reduced to solving a set of integral equations solved, in general, numerically. It is shown that in particular, important for practice, particular cases, this solution is achieved analytically. The paper states the insufficient adequacy of the traditionally used mathematical models for describing fuzzy parameters of the problem, in particular, the demand. Statistical processing of real data on demand shows that the parameters of the membership functions of the corresponding fuzzy numbers are themselves fuzzy numbers. Acceptable mathematical models of the corresponding fuzzy numbers are formulated in terms of bifuzzy mathematics. The relations describing the membership functions of the bifuzzy numbers are given. A formula is obtained for calculating the total losses to storage and from the deficit, taking into account the bifuzzy of demand. In this case, the initial task is reduced to finding the distribution of supplies, at which the maximum value of the total losses does not exceed the permissible value.
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Adhikari, Purnima, and Gyan Bahadur Thapa. "A Note on Feasibility and Optimality of Transportation Problem." Journal of the Institute of Engineering 10, no. 1 (July 31, 2014): 59–68. http://dx.doi.org/10.3126/jie.v10i1.10879.
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Transportation problem is one of the predominant areas of operations research, widely used as a decision making tool in engineering, business management and many other fields. In this paper, we present a brief literature review of transportation problem with its mathematical models in balanced and unbalanced cases. We report the basic feasible solution and hence the methods to attain optimal solution of the balanced transportation problem. Finally, we describe the primal-dual case of the problem with counter examples. DOI: http://dx.doi.org/10.3126/jie.v10i1.10879Journal of the Institute of Engineering, Vol. 10, No. 1, 2014, pp. 59–68
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Hamzaee, Reza G., and Bijan Vasigh. "An Applied Model of Airline Revenue Management." Journal of Travel Research 35, no. 4 (April 1997): 64–68. http://dx.doi.org/10.1177/004728759703500410.
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Demand and revenue management are critical to achieving financial success in the competitive airline industry. This article examines the optimal allocation of available seats to different classes of airfare and provides hypothetical and numerical examples that illustrate the mathematical models.
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Patidar, Rakesh, and Sunil Agrawal. "A mathematical model formulation to design a traditional Indian agri-fresh food supply chain: a case study problem." Benchmarking: An International Journal 27, no. 8 (July 3, 2020): 2341–63. http://dx.doi.org/10.1108/bij-01-2020-0013.
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PurposeThe purpose of this paper is to study and develop supply chain structure of traditional Indian agri-fresh food supply chain (AFSC). This paper proposes a mathematical model to design a traditional Indian AFSC to minimize total distribution cost and post-harvest losses in the chain.Design/methodology/approachThis paper formulates two mathematical models to structure and represent the flow of products in the existing chain. First, a three-echelon, multi-period, multi-product, mixed-integer linear programming (MILP) model is formulated to minimize the total distribution cost incurred in the chain. Further, the developed formulation is extended by considering the perishability of products in the second model.FindingsA real case study problem of Mandsaur district (India) is solved in LINGO 17.0 package to check the validity of the formulated models. The perishable (second) model of AFSC reports better results in terms of costs and post-harvest losses minimization. The results revealed that 92% of the total distribution cost incurred in the transportation of products from farmers to the hubs.Research limitations/implicationsThis paper includes implications for redesigning an existing supply chain network by incorporating an appropriate transportation strategy from farmers to hubs to minimize transportation inefficiency and enhance the profitability of farmers.Practical implicationsThe formulated AFSC model would help managers and policymakers to identify optimal locations for hubs where required infrastructure would be developed.Originality/valueAccording to the author's best knowledge, this paper is the first to design traditional Indian AFSC by considering the perishability of products.
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Zambon, Ivan, Anja Vidović, and Alfred Strauss. "Reliability of Existing Concrete Structures Determined with Physical Models - Carbonation Induced Corrosion." Solid State Phenomena 259 (May 2017): 255–60. http://dx.doi.org/10.4028/www.scientific.net/ssp.259.255.
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The main goal of transportation infrastructure management is to optimize the use of infrastructure in the most beneficiary way while respecting the predefined requirements. One of the crucial parts in management strategy is the prediction of behaviour of vital transportation elements. Used prediction models should accurately describe the process of degradation and allow forecasting of structural condition by considering environment, usage and maintenance actions. Deterioration models can be divided into mathematical (statistical), physical and empirical models. Statistical models are based on data that describe condition of structure, such as for example condition rating. Physical models describe damage-causing processes and empirical models are experience based. The focus of this paper is to present the physical model of carbonation in assessment of performance of existing reinforced concrete structures in transportation networks. Assessment is done through determining the probability of limit state of depassivation. In order to determine the carbonation without testing, a special attention has to be given to environmental and material parameter identification. Herein, the identification takes into account weather specifics and construction practice in Austria. Finally, the reliability of existing reinforced concrete structures for combination of different exposure classes and material characteristics is analysed. Based on the analysis of reliability, the carbonation nomogram for engineering use is presented, showing the reliability indices β for the service life of 50 years.
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Oleg Fyodorovich Danilov, Victor Ivanovich Kolesov, Denis Alexandrovich Sorokin, and Maxim Leonidovich Gulaev. "Study on the Vehicle Linear Dynamic Interval in a Traffic Flow." Communications - Scientific letters of the University of Zilina 23, no. 1 (January 4, 2021): E11—E22. http://dx.doi.org/10.26552/com.c.2021.1.e11-e22.
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The transportation industry of a modern city involves the effective systems for the road traffic management. To manage any object is impossible without understanding its specifics. The tasks of road traffic management are based on mathematical models of traffic flows. The “following the leader” model based on the linear dynamic interval of vehicles has become widely accepted in the model analysis. The paper discusses the mathematical model of the linear dynamic interval of vehicles; the model is identified structurally and parametrically. Coefficients of the model are analyzed in detail; a generalized assessment of the dynamic performance of the traffic flow, evolved in various road conditions, is given. The study has resulted in the proposed basic models for traffic flows that can be used for algorithmic support of the model analysis of traffic flows and the road traffic management.
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Валеева, Альфия, Al'fiya Valeeva, Ольга Семичева, Ol'ga Semicheva, Диляра Валеева, and Dilyara Valeeva. "OPTIMIZATION OF TRANSPORT FLOWS IN SUPPLY CHAIN MANAGEMENT OF THE FOOD COMPANY." Vestnik of Kazan State Agrarian University 12, no. 2 (October 3, 2017): 126–32. http://dx.doi.org/10.12737/article_59ad0be3b6a5e3.39150729.
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Transportation is an important part of the logistics process and supply chain management, so it requires effective management, which is especially true when the organization seeks to meet the needs of its customers and achieve acceptable rates of return on its investments. Shippers should know the opportunities and bottlenecks of the company in terms of transportation at the entrance and exit, be able to choose the mode of transport and the carrier, conclude contracts with the right conditions, analyze the activities of transport brokers, understand the options for transportation by own forces, evaluate the performance of carriers, etc. The methods of optimization of operational planning problems that use linear programming models (LP), the analysis of the transport component in supply chain management, the characteristics of the basic methods of modeling transport problems and the problems of transport routing are considered in the article. The most promising direction in solving the problem of optimizing transport flows is the development of technologies that would combine the advantages of geoinformation systems, mathematical programming and heuristics.
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Barykin, Sergey Evgenievich, Larisa Nikolaevna Borisoglebskaya, Vyacheslav Vasilyevich Provotorov, Irina Vasilievna Kapustina, Sergey Mikhailovich Sergeev, Elena De La Poza Plaza, and Lilya Saychenko. "Sustainability of Management Decisions in a Digital Logistics Network." Sustainability 13, no. 16 (August 18, 2021): 9289. http://dx.doi.org/10.3390/su13169289.
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Globalization has given a powerful impetus to the development of international commercial activity and logistics management systems taking full advantage of cross-border networking. The solution lies at the intersection of information technologies, technical means of machine-to-machine (M2M) interaction, mobile high-speed networks, geolocation, cloud services, and a number of international standards. The current trend towards creating digital logistics platforms has set a number of serious challenges for developers. The most important requirement is the condition of sustainability of the obtained solutions with respect to disturbances in the conditions of logistics activities caused not only by market uncertainty but also by a whole set of unfavorable factors accompanying the transportation process. Within the framework of the presented research, the problem of obtaining the conditions for the stability of solutions obtained on the basis of mathematical models is set. At the same time, the processes of transferring not only discrete but also continuous material flows through complex structured networks are taken into account. This study contains the results of the analysis of the stability of solutions of differential systems of various types that simulate the transfer processes in network media. Initial boundary value problems for evolutionary equations and differential-difference systems are relevant in logistics, both for the discrete transportation of a wide range of goods and for the quasi-continuous transportation of, for example, liquid hydrocarbons. The criterion for the work of a logistics operator is the integral functional. For the mathematical description of the transport process of continuous and discrete media, a wide class of integrable functions are used, which adequately describe the transport of media with a complex internal rheological structure.
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Mirheli, Amir, Mehrdad Tajalli, Rasool Mohebifard, Leila Hajibabai, and Ali Hajbabaie. "Utilization Management of Highway Operations Equipment." Transportation Research Record: Journal of the Transportation Research Board 2674, no. 9 (June 19, 2020): 202–15. http://dx.doi.org/10.1177/0361198120927400.
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This paper presents fleet utilization management processes for highway operations equipment based on actual tracked and reported usage data obtained from transportation agencies. The objective is to minimize total fleet utilization costs, including operational, purchase, and relocation expenses that yield the optimal utilization values and fleet composition of specific equipment types within each region in a year. The framework includes utilization prediction and optimization models, rather than relying on pre-determined utilization thresholds in existing strategies, to avoid under-utilization, over-utilization, or both. The prediction models are structured using equipment explanatory variables with their significant contributing factors, for example, annual equipment usage, annual fuel cost, downtime hours, age, and class code, to predict operational costs. The optimization model is formulated as a set of mathematical formulations, with embedded predictive models, that minimizes the total costs of (i) keeping an asset in-service using predictive annual operational cost functions, (ii) purchasing new assets in a region in the following year, and (iii) relocating assets by capturing the distance between regions. The costs include equipment purchase, operation, maintenance, and transportation expenses. The proposed framework captures the remedial actions to balance under-/over-utilized assets in the fleet in a cost-efficient manner. The proposed methodology is applied to utilization management of a set of operations equipment, and the findings of the dump trucks are presented. Several scenarios are designed to analyze the sensitivity of the costs to various decisions and parameters. The numerical experiments reveal that the proposed framework can facilitate the utilization prediction and management of highway operations equipment and save up to 16.6% in operational costs considering different demand scenarios.
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Zhang, Liye, and W. M. Kim Roddis. "Machine Learning in Updating Predictive Models of Planning and Scheduling Transportation Projects." Transportation Research Record: Journal of the Transportation Research Board 1588, no. 1 (January 1997): 86–94. http://dx.doi.org/10.3141/1588-11.
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A method combining machine learning and regression analysis to automatically and intelligently update predictive models used in the Kansas Department of Transportation’s (KDOT’s) internal management system is presented. The predictive models used by KDOT consist of planning factors (mathematical functions) and base quantities (constants). The duration of a functional unit (defined as a subactivity) is determined by the product of a planning factor and its base quantity. The availability of a large data base on projects executed over the past decade provided the opportunity to develop an automated process updating predictive models based on extracting information from historical data through machine learning. To perform the entire task of updating the predictive models, the learning process consists of three stages. The first stage derives the numerical relationship between the duration of a functional unit and the project attributes recorded in the data base. The second stage finds the functional units with similar behavior—that is, identifies functional units that can be described by the same shared planning factor scaled in terms of their own base quantities. The third stage generates new planning factors and base quantities. A system called PFactor built on the basis of the three-stage learning process shows good performance in updating KDOT’s predictive models.
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Baranov, Georgyi, and Tetyana Danylova. "FORMING THE CONCEPT OF INFORMATION TECHNOLOGY MANAGEMENT OF THE CITIZENS ‘INTELLECTUAL TRANSPORTATION SYSTEM." Avtoshliakhovyk Ukrayiny, no. 1 (257)’ 2019 (March 29, 2020): 12–19. http://dx.doi.org/10.33868/0365-8392-2019-1-257-12-19.
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This article is devoted to the process of modeling dynamic systems of city intelligent transport systems (CITS) with the help of information technologies. The proposed means of fundamentally new integrated subsystems CITS, simultaneously covers arrays of heterogeneous data and use modern neural network technologies to provide information support for the management of transport systems. The safety of the ecological state as a result of the influence of urban traffic in the conditions of industrial centers was formalized for information technologies. Descriptions are executed as mathematical models of complex particles of objects of the city intellectual transport network with the use of heterogeneous fragments. Strategies and methods of systematic management are analyzed for solving complex problems of reducing the ecological load of the city. Ontological descriptions in basic model forms that are focused on ensuring the safety and ecology of urban applications to overcome contamination, risks and threats. This direction involves the creation of systems for automated management of transport infrastructure, which at the moment requires the solution of a range of scientific and technical tasks.The built-in neural network models of dependence will effectively solve planning problems with controlling influences on the infrastructure of urban intelligent transport systems, which will improve the characteristics of the traffic flow and reduce the environmental burden on the environment. The analysis of transport infrastructure and the activities of organizations that have a direct influence on it, has allowed us to propose a scheme for the use of heterogeneous information in the information support of the management of environmental safety and the throughput of the street-road network of urban intelligent transport systems. Keywords: information technology, transport system, situational management, risks, models of the situation.
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Malyshev, M. I. "Research review on improving the efficiency of multimodal transportation based on technological solutions." Civil Aviation High Technologies 23, no. 4 (September 4, 2020): 58–71. http://dx.doi.org/10.26467/2079-0619-2020-23-4-58-71.
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During the process of analyzing Russian and foreign studies in the field of multimodal cargo transportation, existing methods for improving the efficiency of the multimodal transport system are considered. Improving efficiency of multimodal transportation today is possible due to the optimization of the interaction system between the used modes of transport and transportation of goods. Cost reduction, optimization of cargo terminals, the formation and development of the transport corridors network also play an important role in improving this type of transportation. The use of the new capabilities of satellite navigation, as well as the importance of reducing the environmental load and fuel economy should not be underestimated. The minimization of risks throughout the field of multimodal transportation, the improvement of the legislative framework and document management processes are important. To solve these problems, experts propose methods for the operational management of cargo delivery and expedited transportation. Based on these methods, the place of transport logistics in the process of bringing goods to the consumer during multimodal transportation is determined. A methodology for designing a multimodal transport network has been developed, this methodology involves the formation and development of transport corridors, taking into account new conditions for the globalization of transportation. Researches on the organization of transportation using multimodal transport units and technologies (containers, contrailers, "running highway") have been conducted. Based on the theory of controlled networks and integer linear programming methods, the experts developed mathematical models for the distribution of cargo flows, the choice of the most favorable transportation routes, ideal loading of rolling stock, and transportation of goods using the best forwarding algorithm. Methods are proposed for assessing the maximum capacity of the transport network and predicting the interference of weather conditions in the process of goods transportation, based on the Ford-Fulkerson theorem on the maximum flow and minimum cross section and the use of the mathematical apparatus of Markov chains. As a result of the analysis, it was concluded that the lack of a universal methodology for managing multimodal transportation processes on the basis of a telecommunication platform requires the formulation and solution of the important scientific and practical problem - the development of popular organizational and management methods, technological solutions to ensure the effectiveness of multimodal transportation. The totality of the tasks to be solved in this case has important socio-economic significance for the Russian Federation.
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Sivakova, Lenka, Anna Zubkova, and Witalis Pellowski. "Application of a Priori and a Posteriori Estimate on Risk Assessment." Communications - Scientific letters of the University of Zilina 20, no. 2 (June 30, 2018): 56–61. http://dx.doi.org/10.26552/com.c.2018.2.56-61.
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The problem of setting the values and interconnections between elements of the models in the safety, protection and security field, appears as the biggest obstacle in taking crisis management decisions. The article attempts to represent a mathematical approach to modify the expected values and interconnections that can occur in the models describing the protected system in order to minimize errors caused by subjectivity. Here presented procedures are described in the examples of their potential use. The main idea is to focus on improving estimates for better response to reality, then to find new estimates, since those would still be weighed down by the subjectivity caused errors. Based on this premise this article attempts to characterize application of mathematical methods on minimizing the subjectivity caused errors in the models in risk assessment.
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Goncharenko, Andriy Viktorovich. "Airworthiness Support Measures Analogy to the Prospective Roundabouts Alternatives: Theoretical Aspects." Journal of Advanced Transportation 2018 (November 6, 2018): 1–7. http://dx.doi.org/10.1155/2018/9370597.
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The goal of this paper is to investigate theoretically the possible directions of some specified methods for the alternative roundabouts effectiveness modeling and optimization. The out-coming criteria have an economical interpretation. Those are the objective functionals of the alternative roundabouts effectiveness as the profit gained in the course of the traffic flow changes in the view of the integral form. This is modeled taking into consideration the transport infrastructure functioning elements such as the traffic flow of a capacity model. It takes into account two major components of the transportation services which are the alternative roundabouts business’ incomes and expenses relating to the roundabouts transportation worthiness support. The prototypic approach is that one from the aircraft airworthiness support measures models. Corresponding managerial influences with respect to environmental, safety, utility, and other issues, as well as probable impacts, are modeled with the construction of the relevant under-integral expressions, equations, and appropriate coefficients and parameters of the mathematical models. The achieved theoretical results, on the basis of the Euler-Lagrange equation and accepted assumptions, have been checked for the sufficiency of the objective functional maximum presence at the “point” with the use of the conducted computer simulation. The necessary diagrams are plotted in order to illustrate the theoretical contemplations and speculations, as well as to check the correctness of the applied mathematical derivations and visualize the models’ preciseness and abilities. The theoretically constructed mathematical models have a significance of the prognostic values applicability required at the alternative roundabouts effectiveness modeling and optimization ensuring their design progress and evolutions.
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Petridis, Konstantinos, Evangelos Grigoroudis, and Garyfallos Arabatzis. "A goal programming model for a sustainable biomass supply chain network." International Journal of Energy Sector Management 12, no. 1 (April 3, 2018): 79–102. http://dx.doi.org/10.1108/ijesm-09-2017-0002.
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Purpose The design of a biomass supply chain is a problem where multiple stakeholders with often conflicting objectives are involved. To accommodate the aspects stakeholder, the supply chain design should incorporate multiple objectives. In addition to the supply chain design, the management of energy from biomass is a demanding task, as the operation of production of biomass products needs to be aligned with the rest of the operations of the biomass supply chain. The purpose of the paper is to propose a mathematical framework for the optimal design of biomass supply chain. Design/methodology/approach An integrated mathematical framework that models biomass production, transportation and warehousing throughout the nodes of a biomass supply chain is presented. Owing to conflicting objectives, weights are imposed on each aspect, and a 0-1 weighted goal programming mixed-integer linear programming (WGP MILP) programming model is formulated and used for all possible weight representations under environmental, economic and social criteria. Findings The results of the study show that emphasis on the environmental aspect, expressed with high values in the environmental criterion, significantly reduces the level of CO2 emissions derived from the transportation of biomass through the various nodes of the supply chain. Environmental and economic criteria seem to be moving in the same direction for high weight values in the corresponding aspect. From the results, social criterion seems to move to the opposite direction from environmental and economic criteria. Originality/value An integrated mathematical framework is presented modeling biomass production, transportation and warehousing. To the best of the authors’ knowledge, such a model that integrates multiple objectives with supply chain design has not yet been published.
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Novaes, Antonio G. N., Samantha F. Silveira, and Helena C. Medeiros. "Efficiency and productivity analysis of the interstate bus transportation industry in Brazil." Pesquisa Operacional 30, no. 2 (August 2010): 465–85. http://dx.doi.org/10.1590/s0101-74382010000200012.
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Productivity analysis is an important policy making and managerial control tool for assessing the degree to which inputs are utilized in the process of obtaining desired outputs. Data Envelopment Analysis (DEA) is a non-parametric method based on piecewise linear frontiers estimated with the aid of mathematical programming techniques and used, in this paper, to investigate technical, scale and managerial efficiencies associated with interstate bus companies in Brazil (ISBT). Data has been obtained from the web-site of the Brazilian National Agency of Land Transportation (ANTT). Since production factors in the application are constrained by technical and operational reasons, weight restrictions were introduced into the DEA models. The analysis has shown three groups of non-efficient bus firms, with clear differences in productivity. The relative managerial efficiencies of the firms in the non-efficient groups were also computed and analyzed. Finally, an example of benchmarking a non-efficient firm with DEA is presented.
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Riaventin, Veterina Nosadila, Sofyan Dwi Cahyo, and Ivan Kristianto Singgih. "A Model for Developing Existing Ports Considering Economic Impact and Network Connectivity." Sustainability 13, no. 7 (March 26, 2021): 3705. http://dx.doi.org/10.3390/su13073705.
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This study discusses the problem of determining which container port should be developed within an existing network and when this should be carried out. A case study of Indonesia’s port network is presented, where several new ports are to be improved to ensure smooth interisland transportation flows of goods. The effects of the investment on economic consequences and increased network connectivity are assessed. When improving the ports, we consider that the available budget limits the investment. The network connectivity is evaluated by considering the number of reachable ports from the developed ports or transportation time required from other ports within the same port cluster. Based on our knowledge, our study is the first one that discusses the investment problem in multiple container ports under single management, as well as its effects regarding the increase in container flows. The problem is introduced and three mathematical models are proposed and used to solve a real problem. The results show that different models have different improved aspects of container transportation flows—e.g., a balanced improvement of the whole port network (Model 2) and appropriate investment priority for port clusters (Model 3).
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Mamunts, D., S. Sokolov, A. Nyrkov, S. Chernyi, M. Bukhurmetov, and V. Kuznetsov. "Models and Algorithms for Estimation and Minimization of the Risks Associated with Dredging." Transport and Telecommunication Journal 18, no. 2 (June 1, 2017): 139–45. http://dx.doi.org/10.1515/ttj-2017-0013.
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Abstract There are a lot of models and algorithms to minimize risks during dredging operations and they are not without drawbacks. The paper describes the authors’ approach to solving this problem. Mathematical models are proposed and on their basis software is developed. Methods of the risk theory are used to minimize the risks. In this paper a consequence of influence refers to the deviation from the goal expressed in the expected results and the deviation of certain criterion factors. In this case, we mean any measure of quality. In its turn, risk factors reduce criterion factors. These factors are divided into categories - general transportation risks and risks of transporting ground. In these categories, one may derive the following risks - incidents at transport resulting from the impact of a set of random factors including the human one. For risk analysis and management, in addition to identifying critical chains of risk situations, the stochastic model for evaluating the chains is set forth. In order to implement this algorithm, the mathematical package Maple is used, which allows for conducting the required calculations with a software package including the Graph Theory. The paper presents fragments of the code listing.
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Zheng, Yu. "Estimation of Disease Transmission in Multimodal Transportation Networks." Journal of Advanced Transportation 2020 (August 1, 2020): 1–16. http://dx.doi.org/10.1155/2020/8898923.
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Mathematical models are important methods in estimating epidemiological patterns of diseases and predicting the consequences of the spread of diseases. Investigation of risk factors of transportation modes and control of transportation exposures will help prevent disease transmission in the transportation system and protect people’s health. In this paper, a multimodal traffic distribution model is established to estimate the spreading of virus. The analysis is based on the empirical evidence learned from the real transportation network which connects Wuhan with other cities. We consider five mainstream travel modes, namely, auto mode, high-speed railway mode, common railway mode, coach mode, and flight mode. Logit model of economics is used to predict the distribution of trips and the corresponding diseases. The effectiveness of the model is verified with big data of the distribution of COVID-19 virus. We also conduct model-based tests to analyze the role of lockdown on different travel modes. Furthermore, sensitivity analysis is implemented, the results of which assist in policy-making for containing infection transmission through traffic.
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Kravchenko, Olga, Elena Danchenko, and Sergii Martynenko. "APPLICATION OF INFORMATION TECHNOLOGIES FOR MANAGEMENT OF LOGISTIC FLOWS." EUREKA: Physics and Engineering 5 (September 28, 2018): 55–63. http://dx.doi.org/10.21303/2461-4262.2018.00719.
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The process of managing logistics flows is one of the main factors influencing the increase of economic efficiency of production and sales. The development of logistics information systems is a broad niche in the IT field. Application of logistic information systems in the process of management allows you to save money both on wages by the number of employees, and to accelerate the management process in a time interval. Ukraine is the leading country for grain exports. Issues of grain transportation management are considered as an alternative to manual control. The article will discuss issues related to the application of the designed information system "Logistics transportation" to develop an optimal plan for transportation of grain, which clarifies existing models of logistics flows management. To solve the problem, the authors analyzed the existing methods of managing logistic flows: direct methods (northwest method, least cost method, potential method) and methods based on additional calculations. A mathematical model of the problem of logistic flow management is constructed. The initiation solution is executed on the basis of the potentials method with additional conditions implemented in the network representation. The advantage of the used method is that the resulting reference plan is close to optimal computing. Although direct methods get the initial reference plan very quickly, but it is far from optimal. The clarification of the solution of the problem occurs through a block of logical rules. Practical verification of data is carried out on the example of Agrarian firm "Zernotreyd". During the verification, it was found that the chosen management method leads to an increase in efficiency by 4 %.
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İlker Birbil, Ş., Kerem Bülbül, J. B. G. Frenk, and H. M. Mulder. "On EOQ cost models with arbitrary purchase and transportation costs." Journal of Industrial & Management Optimization 11, no. 4 (2015): 1211–45. http://dx.doi.org/10.3934/jimo.2015.11.1211.
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Sun, Binbin, Tiezhu Zhang, Wenqing Ge, Cao Tan, and Song Gao. "Driving energy management of front-and-rear-motor-drive electric vehicle based on hybrid radial basis function." Archives of Transport 49, no. 1 (March 31, 2019): 47–58. http://dx.doi.org/10.5604/01.3001.0013.2775.
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This paper presents mathematical methods to develop a high-efficiency and real-time driving energy management for a front-and-rear-motor-drive electric vehicle (FRMDEV), which is equipped with an induction motor (IM) and a permanent magnet synchronous motor (PMSM). First of all, in order to develop motor-loss models for energy optimization, database of with three factors, which are speed, torque and temperature, was created to characterize motor operation based on HALTON sequence method. The response surface model of motor loss, as the function of the motor-operation database, was developed with the use of Gauss radial basis function (RBF). The accuracy of the motor-loss model was verified according to statistical analysis. Then, in order to create a two-factor energy management strategy, the modification models of the torque required by driver (Td) and the torque distribution coefficient (β) were constructed based on the state of charge (SOC) of battery and the motor temperature, respectively. According to the motor-loss models, the fitness function for optimization was designed, where the influence of the non-work on system consumption was analyzed and calculated. The optimal β was confirmed with the use of the off-line particle swarm optimization (PSO). Moreover, to achieve both high accuracy and real-time performance under random vehicle operation, the predictive model of the optimal β was developed based on the hybrid RBF. The modeling and predictive accuracies of the predictive model were analyzed and verified. Finally, a hardware-in-loop (HIL) test platform was developed and the predictive model was tested. Test results show that, the developed predictive model of β based on hybrid RBF can achieve both real-time and economic performances, which is applicable to engineering application. More importantly, in comparison with the original torque distribution based on rule algorithm, the torque distribution based on hybrid RBF is able to reduce driving energy consumption by 9.51% under urban cycle.
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Gilotra, Manavi, Sarla Pareek, Mandeep Mittal, and Vinti Dhaka. "Effect of Carbon Emission and Human Errors on a Two-Echelon Supply Chain under Permissible Delay in Payments." International Journal of Mathematical, Engineering and Management Sciences 5, no. 2 (April 1, 2020): 225–36. http://dx.doi.org/10.33889/ijmems.2020.5.2.018.
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Environmental worries in production and inventory models have received large attention in inventory management literature. In this paper, an economic production model is proposed with two-echelon supply chain when trade credit is offered by the supplier. This paper proposes human errors of Type I and Type II due to fatigue and inexperience of the inspector during screening. It considers the use of energy for production along with greenhouse gases (GHG) emission from production and transportation operations. The developed model optimizes the environmental and economic performances of the supply chain. Our aim is to explore the effects of human errors during inspection on the emission cost, transportation cost and delay in payment on the replenishment of order sizes and the expected total profit of the retailer. A mathematical model is developed and numerical examples are provided to illustrate the solution procedure.
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Hayat, Mubashir, Bashir Salah, Misbah Ullah, Iftikhar Hussain, and Razaullah Khan. "Shipment Policy for an Economic Production Quantity Model Considering Imperfection and Transportation Cost." Sustainability 12, no. 21 (October 28, 2020): 8964. http://dx.doi.org/10.3390/su12218964.
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Determining replenishment lot size and number of shipments in a traditional production setup has been of great interest among researchers during the last decades. In order to survive modern competition, the manufacturer has to make good decisions about the lot size that is to be shipped to the retailer. Recently, several researchers have developed mathematical models for modelling different real-world situations; however, these models are lacking due to a combination of imperfection in process and shipment lot sizing. Therefore, in the proposed research, shipment policy for an imperfect production setup has been developed with transportation costs taken into consideration. The model analyzed lot sizing for manufacturers and retailers with imperfections in terms of equally sized shipments. Furthermore, an all-unit-discount policy for shipment is considered in the proposed research, and at the end, numerical computation and sensitivity analyses are carried out to gain more insight into the specifications of the model.
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Vos, Bart, and Edwin van den Berg. "Assessing International Allocation Strategies." International Journal of Logistics Management 7, no. 2 (July 1, 1996): 69–84. http://dx.doi.org/10.1108/09574099610805539.
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Allocating the operations of multinational enterprises to geographic locations where performance can be optimized has become an important strategic issue. In view of the continuing growth of international trade and foreign direct investment, managers need systematic procedures to determine global allocation strategies. Available frameworks on global business strategy are typically abstract and generalized, making them less suited for the development of tailor‐made allocation strategies. Quantitative allocation models in operations research tend to be biased towards optimizing mathematical algorithms, making them less suited to support managerial decision making. This paper bridges the gap between generic strategy frameworks and highly quantitative operations research models by presenting a scanning tool to support decision making on strategic allocation issues. An important feature of this tool is to systematically filter available data, intended to quality and quantify critical product, process and market characteristics for specific product classes. The scanning tool has been applied in two cases, involving allocation decisions of a European multinational in the fast moving consumer goods industry.
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Acharya, Ambarish M., Daniela S. Gonzales, Sandra D. Eksioglu, and Sumesh Arora. "An Excel-Based Decision Support System for Supply Chain Design and Management of Biofuels." International Journal of Operations Research and Information Systems 5, no. 4 (October 2014): 26–43. http://dx.doi.org/10.4018/ijoris.2014100102.
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This article presents a Decision Support System (DSS) to aid managers with supply chain (SC) design and logistics management of biomass-for-biofuel production. These tools play a very important role in efficiently managing biomass-for-biofuel SCs and have the potential to reduce the cost of biofuels. The proposed model coordinates the long-term decisions of designing a SC with the medium term decisions of logistics management. This system has the ability to (a) identify locations and capacities for biorefineries, given the availability of biomass and costs; (b) estimate the minimum cost of delivering biofuels, which include transportation, investment, and processing costs; and (c) perform sensitivity analyses with respect to a number of parameters. Visual Basic for Applications (VBA) is used to create the interface of the DSS, and Excel's CPLEX Add-In is used to solve the mathematical models.
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SCHAFFNER, DONALD W. "Utilization of Mathematical Models To Manage Risk of Holding Cold Food without Temperature Control." Journal of Food Protection 76, no. 6 (June 1, 2013): 1085–94. http://dx.doi.org/10.4315/0362-028x.jfp-12-424.
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This document describes the development of a tool to manage the risk of the transportation of cold food without temperature control. The tool uses predictions from ComBase predictor and builds on the 2009 U.S. Food and Drug Administration Model Food Code and supporting scientific data in the Food Code annex. I selected Salmonella spp. and Listeria monocytogenes as the organisms for risk management. Salmonella spp. were selected because they are associated with a wide variety of foods and grow rapidly at temperatures >17°C. L. monocytogenes was selected because it is frequently present in the food processing environment, it was used in the original analysis contained in the Food Code Annex, and it grows relatively rapidly at temperatures <17°C. The suitability of a variety of growth models under changing temperature conditions is largely supported by the published literature. The ComBase predictions under static temperature conditions were validated using 148 ComBase database observations for Salmonella spp. and L. monocytogenes in real foods. The times and temperature changes encompassed by ComBase Predictor models for Salmonella spp. and L. monocytogenes are consistent with published data on consumer food transport to the home from the grocery store and on representative foods from a wholesale cash and carry food service supplier collected as part of this project. The resulting model-based tool will be a useful aid to risk managers and customers of wholesale cash and carry food service suppliers, as well as to anyone interested in assessing and managing the risks posed by holding cold foods out of temperature control in supermarkets, delis, restaurants, cafeterias, and homes.
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Csonka, Bálint, Márton Havas, Csaba Csiszár, and Dávid Földes. "Operational Methods for Charging of Electric Vehicles." Periodica Polytechnica Transportation Engineering 48, no. 4 (July 29, 2020): 369–76. http://dx.doi.org/10.3311/pptr.15853.
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The increasing number of electric vehicles induces a new relationship between the electric vehicles, transportation network and electric network. The deployment of the charging infrastructure is a prerequisite of the widespread of electric vehicles. Furthermore, the charging process and energy management have a significant influence on the operation of both the transportation and electric networks. Therefore, we have elaborated novel operational methods that support the deployment of charging infrastructure for electric cars and buses operating in public bus service, and the energy management. Weighted sum-models were developed to assess candidate sites for public charging stations. The mathematical model of public bus services was elaborated that supports the optimization of static charging infrastructure at bus stops and terminals without schedule adjustments. The flexibility and predictability of charging sessions were identified as the main differences between charging infrastructure deployment for cars and buses. Furthermore, the flows of energy, information and value have been revealed among the components of charging with a focus on commercial locations, which is the basis of energy flow optimization on the smart grid.
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Zissis, Dimitris, Emel Aktas, and Michael Bourlakis. "Collaboration in urban distribution of online grocery orders." International Journal of Logistics Management 29, no. 4 (November 12, 2018): 1196–214. http://dx.doi.org/10.1108/ijlm-11-2017-0303.
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Purpose Population growth, urbanisation and the increased use of online shopping are some of the key challenges affecting the traditional logistics model. The purpose of this paper is to focus on the distribution of grocery products ordered online and the subsequent home delivery and click and collect services offered by online retailers to fulfil these orders. These services are unsustainable due to increased operational costs, carbon emissions, traffic and noise. The main objective of the research is to propose sustainable logistics models to reduce economic, environmental and social costs whilst maintaining service levels. Design/methodology/approach The authors have a mixed methodology based on simulation and mathematical modelling to evaluate the proposed shared logistics model using: primary data from a major UK retailer, secondary data from online retailers and primary data from a consumer survey on preferences for receiving groceries purchased online. Integration of these three data sets serves as input to vehicle routing models that reveal the benefits from collaboration by solving individual distribution problems of two retailers first, followed by the joint distribution problem under single decision maker assumption. Findings The benefits from collaboration could be more than 10 per cent in the distance travelled and 16 per cent in the time required to deliver the orders when two online grocery retailers collaborate in distribution activities. Originality/value The collaborative model developed for the online grocery market incentivises retailers to switch from current unsustainable logistics models to the proposed collaborative models.
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Rushton, Alan, and Richard Saw. "A Methodology For Logistics Strategy Planning." International Journal of Logistics Management 3, no. 1 (January 1, 1992): 46–62. http://dx.doi.org/10.1108/09574099210804804.
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Logistics strategy planning has often been undertaken either as a qualitative overview or as a self‐contained mathematical exercise, considering facility location, facility size and mode of transport. Here, the importance of evaluating the logistics alternatives in parallel with all other business considerations is developed as a standard approach. The role of computerized models for optimization and simulation is shown to be still an important part of the process. The use of the approach is illustrated by a case study considering the logistics of sourcing, manufacture, storage and supply of bulk chemical products throughout the whole of Europe. The alignment of logistics strategy with the business objectives is stressed as a key factor for success.
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Borowska, Maria. "Quantitative methods in the field of economic sciences." VUZF Review 5, no. 2 (June 29, 2020): 22–37. http://dx.doi.org/10.38188/2534-9228.20.2.03.
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The usage of quantitative tools for creating the mathematical models of functioning different economic facilities abounds the opportunity for better understanding and acquaintance of the surrounding reality. A lot of thinkers identify even universality of the particular branch of knowledge with the extent of its ‘mathematization’. Applying mathematical methods so called quantitative provide great and not to overestimate services not only in the science research of technique, physics, astronomy, biology and medicine, but also – within the qualitative methods- in the field of social science in the sphere of the control of the quality of production or in the process of service management or decision making. Complex nature of the social and economic phenomena requires making the usage of the most modern means and the ubiquitous computerization significantly confirms the usefulness of these methods. Progressing ‘mathematization’ and computerization of the science forces creating and applying quantitative (mathematical) models including economic science. The model of operating of studied system was considered in two variants. I. when the process of the product delivery to the store represents inclusively the subsystem of production and the subsystem of the transportation – it could be then said that the level of filling the store up is controlled by the aggregated process of the delivery of the product.
when the process of the product delivery to the store takes into account explicate both the production process and also the operating of transportation subsystem, so it is then the structural process of the product delivery. Both in the aggregated and structural version, the analyses of the functioning of the system was made in three variants of the store filling: intermediate state of the store filling; zero state of the store filling that is lower barrier; the state of full storage of the store, that is the upper barrier. The result of my analyses are two proprietary probabilistic models of system operation which are presented through the system of differential equations both in the aggregated and structural variant. Probabilistic models of functioning of the system in both variants presented throughout the probabilistic model also enable determining sizing prognosis which are characteristic for the functioning of this system. These prognoses are transferred to the unit of the management system and they provide the premises to the streamline of its functioning.
These tools create the basics of theoretical and methodological constructed computer programmes of the informative systems of decision-making support.
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Alyokhina, S., I. Nevliudov, and Yu Romashov. "Safe Transportation of Nuclear Fuel Assemblies by Means of Wheeled Robotic Platforms." Nuclear and Radiation Safety, no. 3(91) (September 17, 2021): 43–50. http://dx.doi.org/10.32918/nrs.2021.3(91).05.
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Certain engineering problems concerning safety of the technological operations of the horizontal transportation of nuclear fuel within the enterprises’ sites were considered. Taking into account current trends in the introduction of robotic systems to reduce the impact of hazardous nuclear materials on personnel, the issue of automated control of the movement of the wheeled robotic platform, which can be used for horizontal transportation of nuclear fuel was studied. The major attention was paid to minimizing the transportation loads on nuclear fuel by means of decreasing the accelerations under its horizontal movement on the robotic wheeled transportation platform, which is a separate issue of the comprehensive safety problem of nuclear materials management.
The research of horizontal movement safety of nuclear fuel by means of the robotic wheeled platforms was limited to defining transportation accelerations and was performed by computer simulations using mathematical models of dynamics and electro-mechanics. The mathematical model of the robotic transport wheeled platform loaded with nuclear fuel with the on-board accelerometer ensuring the required measurements necessary for an automated safe movement control system was built in the form of the Lagrange equations of the second kind and the electro-mechanics equations of the direct current electric motors. The issue of ensuring smooth running during the displacement of a wheeled platform loaded with nuclear fuel was investigated, since especially in this mode the maximum accelerations are observed, which can lead to nuclear fuel damage. Computer simulation was performed using free Scilab software with open program code. It was demonstrated that due to the proper choice of the time algorithm of the voltage of electric motors, it is possible to ensure a small acceleration during the displacement of a robotic wheeled transport platform loaded with nuclear fuel. The obtained result substantiated the possibility of safe horizontal transportation of nuclear fuel on robotic wheeled platforms within the territories of enterprises, which will significantly reduce the harmful impact of hazardous nuclear materials on industrial personnel.
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Yang, Chih-Te, Chia-Huei Ho, Hsiu-Mei Lee, and Liang-Yuh Ouyang. "Supplier-retailer production and inventory models with defective items and inspection errors in non-cooperative and cooperative environments." RAIRO - Operations Research 52, no. 2 (April 2018): 453–71. http://dx.doi.org/10.1051/ro/2017020.
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This paper proposes single-supplier single-retailer production and inventory models for maximizing the supplier and retailer’s profits in non-cooperative and cooperative environments. The effect of defective items and inspection errors are considered in the proposed models. In addition, we consider that the supplier offers the retailer a quantity threshold to absorb transportation costs for promoting the economies of scale of transport. Mathematical analyses are conducted, and optimal equilibrium production and replenishment strategies for the supplier and retailer are derived under non-cooperative and cooperative situations. Subsequently, we establish two algorithms to explain the optimal equilibrium solutions for these cases. Finally, several numerical examples and a sensitivity analysis with respect to major parameters are presented to demonstrate the theoretical results, compare the distinct solutions, and derive managerial insights.
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Aleksander Stasiuk, Valeriy Kuznetsov, Lidia Goncharova, and Petro Hubskyi. "Models of the Computer Intellectualization Optimal Strategy of the Power Supply Fast-Flowing Technological Processes of the Railways Traction Substations." Communications - Scientific letters of the University of Zilina 23, no. 2 (April 1, 2021): C30—C36. http://dx.doi.org/10.26552/com.c.2021.2.c30-c36.
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Based on analysis of the problem of the power supply networks of railways innovative transformation, the direction of research is substantiated related to organization of the optimal strategy of computerized intellectualization of the power supply processes to the railways traction substations. The logical structure of a distributed computer environment developed in the form of graph, which adequately reflects the topology of the organization of the power supply system. A differential mathematical model of the computer architecture of the power supply control is proposed. An intelligent method for finding the optimal strategy for the intellectualization of the power supply processes was proposed to guarantee the specified indicators of the optimal functioning of individual nodes and segments of the power supply management computer network.
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Grabchak, E. P., E. L. Loginov, and V. U. Chinaliev. "Digital transformation of Russia’s thermal power industry management system for optimization of consumers’ expenditures determined by tariffs and prices." Safety and Reliability of Power Industry 13, no. 2 (July 31, 2020): 84–90. http://dx.doi.org/10.24223/1999-5555-2020-13-2-84-90.
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The development and implementation of a strategy for organizational reconfiguration of a digital heat and power super system to streamline the processes of providing structured technological zones with heat makes the basis for creating a coordinated system for optimizing the tariff and price load on heat and electricity consumers in the Russian economy. Providing the industry with a mechanism for regulating the processes of rendering heat energy services based on the transition to the system of Unified Heat-Supply Organizations (ETOs) and ensuring a return on price trend investment in the heat market with the possibility of transferring departmental reporting and analytics to a single regulatory legal basis enables regulating the operation of the power system as a subsystem of the Russian energy sector with a common information technology platform. It is proposed to develop a methodology for constructing mathematical estimates of reliability indicators of provided heat and power services in the form of analytical relationships and simulation models, taking into account the complex nature of the operation of electric power transmission and heat transportation networks as well as information systems that provide processing, storage and distribution of digital data and documents. The key activities are: development of a methodology for constructing mathematical estimates of reliability indicators of provided heat and power services in the form of analytical relationships and simulation models; development of digital methods for detecting hazardous effects; development of algorithms for storing information in the presence of natural and artificial interference; development of digital methods for optimization, modernization and transformation of production chains and processes, control models and planning procedures to neutralize threats to the reliability of provided heat and power services. The result should be the creation of a computer-based information system for modeling impacts on the electric and heat grid facilities.
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MacKenzie, Cameron A., and Aruna Apte. "Modeling disruption in a fresh produce supply chain." International Journal of Logistics Management 28, no. 2 (May 8, 2017): 656–79. http://dx.doi.org/10.1108/ijlm-04-2016-0097.
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Purpose The purpose of this paper is to quantify elements that make fresh produce supply chains (FPSCs) vulnerable to disruptions and to quantify the benefits of different disruption-management strategies. Design/methodology/approach This paper develops a mathematical model of a disruption in a FPSC and analyzes the relationships among variables. Findings The model determines the optimal safety stock as a function of the perishability of the produce, the length of time it takes to find the contamination, the level of demand during the disruption, and the amount of produce that can be rerouted. Applying the model to the 2006 E. coli spinach contamination reveals that the drop in customer demand for fresh spinach plays the largest role in Dole losing sales. Research limitations/implications The model includes several parameters that may be difficult to estimate. Future models can incorporate uncertainty that is inherent in supply chain disruptions. Practical implications The model in this paper can help a supply chain (SC) manager explore the trade-offs of different disruption-management strategies. For example, a SC manager can determine the value of holding additional safety stock vs trying to improve traceability in the SC. Originality/value This paper quantifies and models insights delivered in the qualitative analyses of FPSC disruptions. The theoretical contributions include an analysis of the interaction among safety stock, levels of demand, communication, and traceability parameters in order to help SC managers evaluate different strategies to mitigate the effects of contaminated produce.
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HWANG, Taesung, Minho LEE, Chungwon LEE, and Seungmo KANG. "META-HEURISTIC APPROACH FOR HIGH-DEMAND FACILITY LOCATIONS CONSIDERING TRAFFIC CONGESTION AND GREENHOUSE GAS EMISSION." JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 24, no. 4 (December 16, 2016): 233–44. http://dx.doi.org/10.3846/16486897.2016.1198261.
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Large facilities in urban areas, such as storage facilities, distribution centers, schools, department stores, or public service centers, typically generate high volumes of accessing traffic, causing congestion and becoming major sources of greenhouse gas (GHG) emission. In conventional facility-location models, only facility construction costs and fixed transportation costs connecting customers and facilities are included, without consideration of traffic congestion and the subsequent GHG emission costs. This study proposes methods to find high-demand facility locations with incorporation of the traffic congestion and GHG emission costs incurred by both existing roadway traffic and facility users into the total cost. Tabu search and memetic algorithms were developed and tested with a conventional genetic algorithm in a variety of networks to solve the proposed mathematical model. A case study to determine the total number and locations of community service centers under multiple scenarios in Incheon City is then presented. The results demonstrate that the proposed approach can significantly reduce both the transportation and GHG emission costs compared to the conventional facility-location model. This effort will be useful for decision makers and transportation planners in the analysis of network-wise impacts of traffic congestion and vehicle emission when deciding the locations of high demand facilities in urban areas.
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Juškevičius, P. "PROCEDURES OF CITY TRANSPORT SYSTEMS' PLANNING/MIESTŲ SUSISIEKIMO SISTEMŲ PLANAVIMO PROCESO PROCEDŪROS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 1, no. 4 (December 31, 1995): 45–66. http://dx.doi.org/10.3846/13921525.1995.10531533.
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The article starts with looking into a treatment of the objects of city transport systems planning: administrative (determined) and systematic approach, that are of importance for the principles of planning and its quality. The major shortages of the traditional planning are the following: its determination, narrow functional attitude towards the processes of transportation, lack of evaluation of the interrelations between a city structure and its transport system. There are several obstacles to shift to the planning of higher quality, namely poorly arranged information supply, shortage of mathematical models for transport processes and relevant soft ware. Considering the gained experience of transport system planning and professional knowledge on transport systems, a new methodology of planning is presented. A major stress here is put on the complex of transport system functioning, the consequences and the price.
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Suraraksa and Shin. "Urban Transportation Network Design for Fresh Fruit and Vegetables Using GIS–The Case of Bangkok." Applied Sciences 9, no. 23 (November 22, 2019): 5048. http://dx.doi.org/10.3390/app9235048.
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A cold chain for perishable fresh products aims to preserve the quality of the products under the control of a predefined temperature range. To satisfy the delivery conditions within appropriate time windows, the most critical operations in cold chain management is the transportation and distribution of fresh products. Due to rapid population growth and increasing demand for high-quality fresh foods, it becomes critical to develop advanced transportation and distribution networks for fresh products, particularly in urban areas. This research aims to design different scenarios based on mathematical models for fresh products transportation and distribution network in the Bangkok metropolitan area using Geographic Information system (GIS). The proposed methodology integrates location–allocation and vehicle routing problem analysis. The performance of all possible scenarios is evaluated and compared by considering the number of required distribution centers and trucks, total travel time, total travel distance, as well as fairness among drivers. The results of the scenario analysis highlight that the alternative scenarios show a better performance as compared to the current network. In addition, the administrator can make a different decision among several alternatives by considering different aspects, such as investment cost, operating cost, and balance of using available resources. Therefore, it may help a public officer to design the fresh products logistics network considering actual demand and traffic conditions in Bangkok.
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Borysova, T., G. Monastyrskyi, A. Zielinska, and M. Barczak. "Innovation Activity Development of Urban Public Transport Service Providers: Multifactor Economic and Mathematical Model." Marketing and Management of Innovations, no. 4 (2019): 98–109. http://dx.doi.org/10.21272/mmi.2019.4-08.
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Systematization literary sources and approaches for solving the problem of ecologists of «smart» city indicates that among factors that probably can affect the innovativeness of Ukrainian providers of urban public transport services have been used environmental factor, marketing expenses, financial potential, wear rate, level of quality of service, level of management skills, market share, tariff for passenger transportation. The purpose of the study is to identify the ways to improve the innovativeness of urban public transport service providers of the regional centres of Ukraine. The main aim of the research is to estimate the impact of several factor variables on the resulting attribute used multivariate regression analysis, which provided an adequate model. A significant contribution to the development of the theory and methodology of management of urban public transport enterprises were made by Nunes, Krasnyanskiy, Umpleby, Walters, Huang, Morchadze. The results of the evaluation of the innovativeness of Ukrainian providers of urban public transport services carried out based on the mathematical multifactor model are presented in the article. In January-March 2018, the authors initiated a study on the current state of urban public transport in regional Ukrainian cities. Methodological tools of the research were multivariate correlation-regression analysis and survey (the requests for public information were submitted by the Law of Ukraine «On Access to Public Information» to all city councils of Ukraine's regions except temporarily occupied territories). The study included a survey of 20 experts (marketers and experienced managers of transport companies) to determine weighting factors and the level of innovativeness through questionnaires. The expert evaluation was carried out using the marks method. The research has shown that the size of the innovativeness of providers of public transport services can be successfully interpreted through functional and statistical dependencies, which reflect the general and individual laws of the development of such entities using multi-factor mathematical models. The econometric model was tested for the adequacy with the Fisher criterion and the presence of autocorrelation. The research empirically confirms and theoretically proves thatsuch controllable factors are an environmental factor, financial potential, level of quality of service, level of management skills, the tariff for passenger transportation. The model can be used to predict the influence of controllable factors at the level of the innovativeness of providers of urban public transport services. The results of the research can be useful for scientific and practical workers, teachers, students of higher educational establishments. Keywords: econometric model, factors of innovativeness, innovativeness, urban transport, ecologists.
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Arango, Ivan, Carlos Lopez, and Alejandro Ceren. "Improving the Autonomy of a Mid-Drive Motor Electric Bicycle Based on System Efficiency Maps and Its Performance." World Electric Vehicle Journal 12, no. 2 (April 8, 2021): 59. http://dx.doi.org/10.3390/wevj12020059.
Full textAbstract:
Around the world, the e-bike has evolved from a recreational and sports object to an increasingly used means of transportation. Due to this, improving aspects such as range and energy efficiency has become very relevant. This article presents experimental models for the components’ efficiency of a mid-drive motor e-bike (charger; battery; and controller, motor, and reduction gears subsystem), and integrates them with previously elaborated models for the chain transmission system, thus generating an overall efficiency map of the e-bike. The range of the electric bicycle is analyzed by integrating the efficiency map of the system and its performance mathematical model, aiming to determine the per unit of distance battery energy consumption. The above-mentioned calculations are applied to develop a management strategy that can determine the optimal assistance level and chain transmission ratio, maximizing range and leaving speed unaffected. The driving strategy was compared against other driving techniques using computational analysis, this allowed for the observation of the proposed strategy improving the system’s range by reducing the battery energy consumption.
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Piqueira, José R. C., and Felipe Barbosa Cesar. "Dynamical Models for Computer Viruses Propagation." Mathematical Problems in Engineering 2008 (2008): 1–11. http://dx.doi.org/10.1155/2008/940526.
Full textAbstract:
Nowadays, digital computer systems and networks are the main engineering tools, being used in planning, design, operation, and control of all sizes of building, transportation, machinery, business, and life maintaining devices. Consequently, computer viruses became one of the most important sources of uncertainty, contributing to decrease the reliability of vital activities. A lot of antivirus programs have been developed, but they are limited to detecting and removing infections, based on previous knowledge of the virus code. In spite of having good adaptation capability, these programs work just as vaccines against diseases and are not able to prevent new infections based on the network state. Here, a trial on modeling computer viruses propagation dynamics relates it to other notable events occurring in the network permitting to establish preventive policies in the network management. Data from three different viruses are collected in the Internet and two different identification techniques, autoregressive and Fourier analyses, are applied showing that it is possible to forecast the dynamics of a new virus propagation by using the data collected from other viruses that formerly infected the network.