scholarly journals A MATHEMATICAL MODEL OF SELECTING TRANSPORT FACILITIES FOR MULTIMODAL FREIGHT TRANSPORTATION

Transport ◽  
2008 ◽  
Vol 23 (1) ◽  
pp. 10-15 ◽  
Author(s):  
Olga Lingaitienė

A system of functional relationships between speed, traffic safety and costs, based on a set of criteria describing transportation quality is presented. The overall technological costs of transportation can be determined, when the costs of using road, rail and sea transport are calculated. For this purpose, a case study of creating a mathematical model for choosing the optimal route, taking into account time, costs and safety of transportation, is considered. The model evaluates the time of freight loading and storage at terminals. The total time of transportation, loading and storage differs for particular routes, depending on route structure and terminal operation. Freight safety is calculated in terms of insurance payments, depending on the type of goods, route and time of transportation. The model may be used for calculating any route, when applying the data on particular parks of vehicles.

Author(s):  
O. Borovyk ◽  
V. Kupelskiy

The rapid response border commandant's office is a structural unit of the border detachment, designed to protect and strengthen the protection of a certain section of the state border, and must quickly redeploy its forces and assets. The success of the tasks assigned to the unit depends largely on the timeliness of arrival at the destination. Operational transportation of a significant amount of weapons, personnel and dissimilar cargoes on land is carried out using equipment. At the preparatory stage of the organization of transportation, the problem of forming the optimal composition of the convoy of equipment is solved. The existing road network provides a sufficiently large number of traffic routes between the starting and ending points. Moreover, this takes place even for insignificant distances between points of departure and destination. The specified conditions for multivariance in the selection. In addition, the choice of the route of movement depends on many auxiliary conditions: driver training, technical characteristics and reliability of vehicles, traffic safety, road and environmental conditions, distance and timing of transportation, and the like. Poor accounting of these factors in the aggregate may lead to the choice of an irrational route of movement, will not ensure the timely arrival of the unit at the destination, and may lead to the failure to fulfill certain tasks. Therefore, the task of choosing the optimal route of movement of the column of equipment is relevant. At the substantive level, the task looks like the justification of the mathematical model for choosing the optimal route for the column of equipment, if the criterion of optimality is minimizing the time it takes to move from the starting point to the destination. The authors formed a mathematical model of the given problem, proposed an algorithm for its solution for three cases: discrete-stochastic, discretely-determined and continuously-indefinite, and the corresponding software was developed. The choice of routes is carried out for three options, taking into account the fact that the change in the weights of the ribs can be carried out: at times when the column is at a certain vertex of the graph, and the update of the matrix of weights is carried out precisely at these moments. This is the case when a decision on the further route of movement is formed at the road branching points, taking into account the situation, the status of individual sections changes dynamically and data for which appears periodically; at times when the column is at a certain vertex of the graph, and for these moments, the matrix of weights that will occur when the column hits the vertex are known in advance. This is the case when a decision on the route of movement can be formed at the beginning of the movement, taking into account the known situation on the state of the roads, dynamically change, but data on which can be taken into account in advance; randomly depending on the speed of the column at a fixed point in time for which the column speed function is known.


2018 ◽  
Vol 13 (Number 1) ◽  
pp. 21-29
Author(s):  
Zakiah Hashim ◽  
Wan Laailatul Hanim Mat Desa ◽  
Hurul Ain Aziz ◽  
Nur Mariana Zaimah Mohd Zaki

This paper presents a real case study to determine the optimal tourist route at Langkawi Island. The Langkawi Island was selected as thecase study because normally, tourist travel to this island will drive the rented car as the primary mode of transport. Thus, the aim of this paper is to develop a mathematical model to find an optimal route for tourist to travel to their interesting places around Langkawi Island. In order to solve the problem, Greedy method was applied in this study and MATLAB version 7.8 has been used to get the solution. The result obtained shows that Nearest Greedy Insertion method gives better result compared to the Nearest Greedy method. The minimum value of the route selection gives effect to the cost of travelling. Therefore, from this study, the best route that connect from one interesting place to others place can be suggested to the tourist as guidance. In addition, tourist can save their time and money to visit all interesting places in this study.


2008 ◽  
Vol 59 (10) ◽  
Author(s):  
Delia Perju ◽  
Harieta Pirlea ◽  
Gabriela-Alina Brusturean ◽  
Dana Silaghi-Perju ◽  
Sorin Marinescu

The European laws and recently the Romanian ones impose more and more strict norms to the large nitrogen dioxide polluters. They are obligated to continuously improve the installations and products so that they limit and reduce the nitrogen dioxide pollution, because it has negative effects on the human health and environment. In this paper are presented these researches made within a case study for the Timi�oara municipality, regarding the modeling and simulation of the nitrogen dioxide dispersion phenomenon coming from various sources in atmosphere with the help of analytical-experimental methods. The mathematical model resulting from these researches is accurately enough to describe the real situation. This was confirmed by comparing the results obtained based on the model with real experimental values.


2019 ◽  
Author(s):  
Michael Petronis ◽  
◽  
Vincent Twomey ◽  
William McCarthy ◽  
Craig MaGee
Keyword(s):  

2021 ◽  
Vol 57 ◽  
pp. 126939
Author(s):  
Mari Ariluoma ◽  
Juudit Ottelin ◽  
Ranja Hautamäki ◽  
Eeva-Maria Tuhkanen ◽  
Miia Mänttäri

2011 ◽  
Vol 261-263 ◽  
pp. 1709-1713
Author(s):  
Meng Yang ◽  
Xiao Min Liu

This paper introduces a new failure mode pattern of soil slope – the logarithmic spiral slippery fracture. A mathematical model for the logarithmic spiral slippery fracture is established, taking the anti-shear function of the soil-nailing into consideration. The shear of soil-nailing, axial force, and the safety coefficients based on the limiting equilibrium method are derived, leading to an accurate stability analysis of the strengthening of soil slope. A case study shows that the anti-shear function of the soil-nailing can be significant and should not be ignored in engineering design.


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