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Design and implementation of vehicle routing problem software library
Drobný, Michal ; Gála, Libor (advisor) ; Melechovský, Jan (referee)
Various types of transportation issues are a common practice. The issue may be approached mainly as the distribution of products from suppliers to consumers while minimising distribution costs. The difference of real transportation issues predominantly relates to the considered restrictions, such as capacities of vehicles and orders, time windows and other special distribution restrictions. There are some specialized commercial products for optimizing distribution costs presented on the market. These are often part of larger frameworks, which also provides other services such as vehicle tracking, warehouse location, ride statements etc. These products provide cloud services fully customized according to the customer. This work aims to design and construct an open source software library for solving vehicle routing problem, which will be able to reflect requirements of simplicity, scalability and portability. The constructed library can serve not only as an open source solution for vehicle routing problems, but also as a tool for testing new methods studied on university premises. The work is divided into several parts. In the first part we define the goals of this work, we define the vehicle routing problem and we describe the principles of the solution. In the next section, we propose the structure of the software, we discuss the choice of aids and document a design phase. The last part deals with the implementation phase, validation phase and real use of the software.
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Milkrun optimization in automotive industry
Václavů, Tomáš ; Fábry, Jan (advisor) ; Pelikán, Jan (referee)
At the basic there is a connection between operation research and automotive logistics. The supply chain in this type of industry is hard to coordinate and flexibility is considered as a main key indicator. Companies increase their competitiveness through the optimization of supply chain and try to take control of every flow or a process. This idea goes throughout the departments. The main concept, which is about a connection of whole supply chain with information flow means, that there isn't need of stock and every input is highly available on time and in requested quantity and quality. This thesis describes inbound logistics and introduces some of the methods used for planning vehicle routes. In our situation which is based on car maker data set was chosen a group of a suppliers for the analysis. We used vehicle routing problem with some modifications, heuristics based on the covering problem. Founded solution was compared with the present state.
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Use of savings algorithm in messenger problem
Gőtz, Ondřej ; Fábry, Jan (advisor) ; Kobzareva, Maria (referee)
The diploma thesis deals with the use of heuristic methods for solving messenger problems. The first part focuses on the proposed vehicle routing problems, especially on travelling salesman problems and the messenger problems. For individual problems are theoretically discussed mathematical models for variants with one or more vehicles and the expansion of the use of time windows and capacity constraints. The second part introduces heuristic algorithms for the method of nearest neighbour, savings method, insertion method and the exchange method on the travelling salesman problems. Then all of the mentioned algorithms are modified for use in three variants of messenger problem. First, the disposition of one vehicle, the second allows more messengers in the same starting point and the last option is more messengers at different starting points. The last part describes computational experiments and comparison of results provided by different methods. The diploma thesis includes application for solving messenger problems using savings methods programmed in Visual Basic for Application in MS Excel.
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Optimization of distribution of bakery goods
Gebauerová, Monika ; Fábry, Jan (advisor) ; Pelikán, Jan (referee)
This thesis deals with the optimization of distribution of bakery products. Firstly there are the fundamental types of vehicle routing problems and their optimization models introduced. Next part is dedicated to heuristic algorithms. The heuristic methods are introduced in general, then there are the chosen methods described. Later there are two chosen algorithms formulated. First one based on the nearest neighbour method and another one based on the savings algorithm. Both of algorithms were programmed in the Visual Basic of Applications MS Excel 2010. These algorithms were applied for the solution of the real problem dealing with the distribution of goods. The bakery company has provided the data about its customers for this purpose. The last part of this thesis is dedicated to the summary and comparison of the solution of the assigned problem that was gained by the proposed algorithms with the solution that the bakery company has put into practice.
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Optimalization of the beer distribution in Jesenicko
Krčmář, Pavel ; Fábry, Jan (advisor) ; Suchánková, Tereza (referee)
The thesis deals with application of models of routing problems on a real problem, beer distribution in Jesenicko region provided by Viden plus, a.s. The goal of the thesis is to optimize daily distributional routes for two vehicles with different capacities. Total distance has to be minimized respecting time and capacity limits. In case the optimal solution is not found, sub-optimal solution will be accepted. Solutions are calculated with use of the optimization software LINGO and some heuristic methods. Models of travelling salesman problem and vehicle routing problem are used to find the solutions. Results are compared to the current state of distributional routes in conclusion of the thesis.
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An optimization of lunch distribution
Václavů, Tomáš ; Fábry, Jan (advisor) ; Borovička, Adam (referee)
The purpose of this bachelor thesis is optimization of lunch distribution. At first the company and the task for optimization will be introduced. Then real are modified to be used for optimization. A distance matrix is created with suitable reduction of requests to easier the problem. In the theoretical part the suitable models of vehicle routing problem will be introduced with an extension to vehicle routing problem with time windows. Chosen model is fitted to our problem to count the solution. There is a real data software optimization. To find the best feasible solution we use different software products. Usable solution will be tested in probationary distribution after check. Finally there is a request of feedback.
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Heineken Beer Distribution Optimalisation
Vršecká, Renáta ; Fábry, Jan (advisor) ; Pelikán, Jan (referee)
This thesis deals with real logistic problem of the Heineken CZ Company. The company sets down an itinerary for each vehicle to distribute its goods to particular customers on daily basis. These itineraries are created manually, only with the skill of experienced driver. The goal of this thesis is to find a solution with an algorithm, which will be able to set optimal itineraries of all vehicles, so the total distance and therefore operating costs are minimized, with only the knowledge of distances between each two nodes.
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Optimalization of distribution process in trading company
Scigel, Pavel ; Jablonský, Josef (advisor) ; Kořenář, Václav (referee)
The thesis deals with distribution problems and their methods for their solution. They belong to one of the most often used optimization models in practice. The thesis describes background for using modelling support systems LINGO and MPL for Windows. The modelling languages allow solving all problems described in the theoretical part including the travelling salesman problem and the vehicle routing problem. There are described basic heuristic methods for problems with higher number of variables in this work as well. The thesis includes the description of a real situation for which it is possible to apply travelling salesman problem or vehicle routing problem models. It is a complex problem which cannot be solved by exact methods but heuristic methods must be used. The problem is going to be solved by means of MS Excel together with Visual Basic for Applications using the heuristic method of nearest neighbour.
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Application of Heuristics on Vehicle Routing Problem
Gerlich, Michal ; Fábry, Jan (advisor) ; Pelikán, Jan (referee)
This thesis deals with solving a real case from one specific part of Operations Research -- Discrete Models. The case can be classified as Vehicle Routing Problem (VRP) which is a subset of classical Travelling Salesman Problem (TSP). The VRP is modified TSP when requirements of customers and capacities of trucks play role. The data needed for calculations were taken from the real situation of Pivovar Svijany a.s. The problem can be defined as VRP with cars with different capacities and split delivery. Even though the mathematic model of the problem is known and described in the thesis, the size of the problem is too big to be optimized. Therefore heuristic was used to solve it. Because of the good computational results in the past the savings algorithm was chosen. Its model was set using Visual Basic for Applications (VBA). The thesis (among others) analyses the sensitivity of the output on the values of the factors that can be chosen by the analyst. At the end of the thesis the best found solution is presented and the initial and the new scheme of the circles are compared.
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Optimization of Business Trips Schedule -Vehicle Routing Problem Application
Dvořáčková, Tereza ; Šindelářová, Irena (advisor) ; Skočdopolová, Veronika (referee)
My bachelor thesis deals with the special linear programming problems, so called distribution problems. Special attention is paid to the travelling salesman problem (TSP) and the vehicle routing problem (VRP). The introductory theoretical chapters explain mathematical models of selected distribution problems, as well the description of some heuristic methods for solving the TSP problem. The modifications of these heuristics are then applied to the real vehicle routing problem. In that real task (included in the last part of this thesis) the daily schedule for a sales representative of one unnamed Czech company is optimized. That sales representative regularly attends customers in his assigned territory and my optimization is focused on saving his time. The results obtained by means of heuristics as well by LINGO software are compared in the thesis conclusion. In chapter 3.5 the real task was modified by means of introducing new limitations, so-called time windows. The results of my thesis will be present to the company.
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