|
|
Walks in time-dymanic graph model
Beliš, Marek ; Pangrác, Ondřej (advisor) ; Böhm, Martin (referee)
Orienteering with moving control points can be represented as a graph model with ranked vertices and oriented edges. The rank of vertex depends on the actual time. Searching for the most optimised walk through this graph is exponentially difficult problem which can be in real-time solved only with limiting conditions and using of heuristics. SMIK solver software provides implemented heuristics for searching the best walk in several ways. In the thesis we can find description of the problem and algorithms, programming documentation with description of used methods and comparation of results to the real competition. Powered by TCPDF (www.tcpdf.org)
|
|
|
Optimization of ditribution of products
Bílek, Jan ; Pangrác, Ondřej (advisor) ; Šámal, Robert (referee)
The thesis deals with the Vehicle Routing problem with vehicles having limited capacity. We mainly focus on the variant with heterogeneous fleet of vehicles each having its variable and fixed costs. Algorithm designed to solve the problem first finds an feasible initial solution by probabilistically modified Clarke-Wright savings method and then improves it by techniques based on local search. Obtained results are compared with state-of-the-art algorithms on well- known benchmarks. The implementation of the algorithm in Java is part of the work. 1
|
|
|
Vehicle Routing Problem
Kafka, Ondřej ; Branda, Martin (advisor) ; Hanzák, Tomáš (referee)
The thesis deals with optimization problems which arise at distribution planning. These problems can often be easily formulated as integer programming problems, but rarely can be solved using mixed integer programming techniques. Therefore, it is necessary to study the efficiency of heuristic algorithms. The main focus of the thesis is on the vehicle routing problem with time windows. A tabu search algorithm for this problem was developed and implemented. It uses integer programming to solve the set partitioning problem in order to find optimal distribution of all customers into feasible routes found during the search. The results of the classical integer programming approach, basic insertion heuristic and presented tabu search algorithm are compared in a numerical study.
|
|
|
Operation optimization in wholesale warehouses
Kolárik, Jan ; Pangrác, Ondřej (advisor) ; Hladík, Milan (referee)
The goal of this work is to choose a strategy for given warehouse that will increase the efficiency of its operation. This is primarily about reducing customer downtime and minimizing the distance travelled by handling machines. The final program can generate warehouse structure according to given parameters and then evaluate monitored variables from simulated operations based on optimization techniques used. There is also a planar and spatial warehouse model available, which helps to visualize what is actually happening in the warehouse. The program could serve as an auxiliary tool in the organizing of wholesale warehouse operations and reduce costs required for its operation.
|
|
| |
|
|
Comparison of Methods for Travelling Salesman Problem
Šušová, Lucia ; Janoušek, Vladimír (referee) ; Rozman, Jaroslav (advisor)
This work is about comparison of methods for solving the traveling salesman problem. There are many algorithms for finding solution of this NP complete problem but it is not easy to choose the right one. Main goal of this thesis is experimental methods comparison between each other. Reader is going to learn what result she can expect if she chooses certain algorithm for finding the path. First part is focused on theoretical basics where is described all needed information for understanding the problem. Second part describes single heuristics and methods for solving these problems. The methods are divided into groups by principle of working. Next part contains experimental comparison of methods. This comparison was done based on own implementation of single heuristics. The following part of this work contains information about this implementation and also describes comparison application. Next possible steps of this project are described in conclusion.
|
|
|
Mathematical models for transportation problems
Votavová, Helena ; Novotný, Jan (referee) ; Popela, Pavel (advisor)
The thesis deals with modelling and solution techniques for the selected transportation problems. Firstly, historical remarks and application-related comments are introduced. Then the selected transportation problems are defined and mathematical programming and graph theory concepts are utilised to model them. The travelling salesman problem and suitable algorithms are under focus. The original implementation in GAMS and Python is discussed. Algorithms have been tested for the instance based on the set of 73 towns in the Czech Republic. Finally, the test results are evaluated and compared.
|
|
|
Heuristics for capacitated messenger problem
Přibylová, Lenka ; Fábry, Jan (advisor) ; Pelikán, Jan (referee)
This diploma thesis deals with static and dynamic capacitated messenger problem and its solving with heuristic algorithms. Different variations of the capacitated messenger problem were considered, with a single messenger or multiple messengers, with one depot or multiple depots in case of multiple messengers. Limited time for route realization was another modification that was considered. Modified nearest neighbour method, modified insertion method and modified exchange method were used to solve the problem. The main contribution of the thesis is deriving heuristics for described types of messenger problem and programming the algorithms in VBA (Visual Basic for Applications) in MS Excel. The results of computational experiments indicate that modified nearest neighbour method leads to better outcomes in static multiple messenger problems with a single depot, while modified insertion method is associated with lower values of objective function in static multiple messenger problem with multiple depots. Modified exchange method improves original solutions. Modified insertion method was approved for solving dynamic multiple messenger problems.
|
|
|
Psychological principles in techniques of social engineering
Pohorelec, Pavel ; Sigmund, Tomáš (advisor) ; Kašparová, Eva (referee)
Social engineering is type of attack, usable against an organization or individual. It focuses on weaknesses of human factor. In recent times, characterized by anonymity, fast pace and focus on technologies presents this way of attack a dangerous threat. Human factor tends to be underestimated in defense, into which organizations invest large amounts of money. Even though social engineering has been written about many times, most of work has been focused more on technical part, and explaining techniques of social engineering has been left out. The goal of this paper is explaining these techniques from psychological point of view, and using that as a basis for defense for organizations, threaten by social engineering attack. In first part, this work describes two main themes -- social engineering and social psychology. Afterwards, it describes principles, which are used in social engineering attack, and ways in which social engineering uses them. In second part are these information used to analyze several practical examples of social engineering attack. Then, they are used to formulate practical advices to defend against social engineering attack.
|
|
|
Application of heuristic methods in real vehicle routing problem
Slavíková, Monika ; Fábry, Jan (advisor) ; Kobzareva, Maria (referee)
This thesis is continuation of the bachelor thesis "Model of delivery routes and placement logistics centers with opportunities of their optimization". It is about distribution problems and specifically a vehicle routing problem. The aim of this thesis is finding a solution of the vehicle routing problem which will be used repeatedly in the firm. The main task is achieving the lowest costs (total kilometers) with maximum utilization of vehicle capacity; in such conditions that all requirements of logistics centers will be satisfied and maximal capacity of vehicle will be tolerated. For calculation was used a solver Gurobi 6.0.3 in system MPL for Windows 4.2, which won't, however, provide the optimal solution and problem solving takes too long time. Next for calculation was used heuristics insert method and is written by VBA (Visual Basic for Applications) in MS Excel. Finally, there is a comparison of these methods with the original solution of the vehicle routing plan and solution of the bachelor thesis. Then the computational experiment was done, which tested effect to result, if other distribution center (starting point) will be bulit. The computational experiment was consist from heuristic insert method, solver Gurobi and heuristic saving algorithm from bachelor thesis.
|
guest ::
