|
|
Distributed Tool for Extraction of Information from Network Flows
Sedlák, Michal ; Grégr, Matěj (referee) ; Žádník, Martin (advisor)
This work deals with the extraction of information from flow records that are the result of network monitoring by the IPFIX system. The goal of the work is to design a tool that allows querying stored network flows created by the open-source collector IPFIXcol2. Querying is performed with the highest possible efficiency and performance in mind, which is achieved by using appropriate data structures and thread-level parallelization, as well as by using multiple machines.
|
|
|
Advanced Optimization of Network Flows
Cabalka, Matouš ; Hrabec, Dušan (referee) ; Popela, Pavel (advisor)
The master’s thesis focuses on the optimization models in logistics with emphasis on the network interdiction problem. The brief introduction is followed by two overview chapters - graph theory and mathematical programming. Important definitions strongly related to network interdiction problems are introduced in the chapter named Basic concepts of graph theory. Necessary theorems used for solving problems are following the definitions. Next chapter named Introduction to mathematical programming firstly contains concepts from linear programming. Definitions and theorems are chosen with respect to the following maximum flow problem and the derived dual problem. Concepts of stochastic optimization follow. In the fifth chapter, we discuss deterministic models of the network interdiction. Stochastic models of the network interdiction follow in the next chapter. All models are implemented in programmes written in the programming language GAMS, the codes are attached.
|
|
|
Network flows and their modifications
Bitara, Matúš ; Hošek, Jaromír (referee) ; Popela, Pavel (advisor)
The thesis deals with optimization models in transportation problems. Brief introduction to graph theory and linear programming is followed by transportation problem of waste transport. Then there is a part with real data applied to the territory of the Czech Republic. After that the user interface created in Visual Basic programming language is explained. In conclusion computational results are discussed as well as their possible improvement.
|
|
|
Selected Advanced Stochastic Programming Models
Brzobohatý, Jan ; Hrabec, Dušan (referee) ; Popela, Pavel (advisor)
This diploma thesis deals with stochastic dominance. The goal is to lay the foundations for defining stochastic dominance, to describe its properties and to explain this concept on simple examples. Another goal is to apply this concept to network problems with random price. Examples in this thesis also contain solutions and python code how to find them.
|
|
|
IP Flow Filter
Štoffa, Imrich ; Krobot, Pavel (referee) ; Wrona, Jan (advisor)
This thesis is focused on unification of filtering languages used by IP flow collecting program and library for their analysis. At the moment these implementations use different filtering modules and file formats. Because of this, inconsistencies in results arise and as a response to this, creation of one filtering module was proposed as part of effort to better integrate collection and analysis of IP flows using these programs. The one filtering module aims to provide one implementation and support for popular filtering language for use in the programs. Thesis contains theoretical introduction to flow monitoring in networks, describes algorithms useful for evaluation of conditions on flow records and packets. The core of authors work is design and implementation of the filtering module and its wrappers for the collector and analysis library. Results of performance tests and evaluation of features can be found in the thesis's conclusion.
|
|
|
Optimization of rail waste transportation
Ambrozková, Anna ; Hrabec, Dušan (referee) ; Pavlas, Martin (advisor)
The bachelor thesis focuses on optimization of rail waste transportation. Theoretical part is about graph theory and optimization, where is introduced for example representation of graphs, network flows or linear programming. Practical part deals with comparison of road and rail networks, motivational example and at least with the application on real data of whole Czech Republic.
|
|
|
Traffic assignment optimization models
Holešovský, Jan ; Mrázková, Eva (referee) ; Popela, Pavel (advisor)
Optimalizace toku v síti je klasickou aplikací matematického programování. Tyto modely mají, mimo jiné, široké uplatnění také v logistice, kde se tak snažíme docílit optimálního rozdělení dopravy, např. vzhledem k maximalizaci zisku, či minimalizaci nákladů. Toto pojetí ovšem často problém idealizuje, poněvadž předpokládá existenci jediného rozhodovatele. Takový přístup je možný ve striktně organizovaných sítích jako např. v logistických sítích přepravních společností, železničních sítích či armádním zásobování. Úloha ''Traffic Assignment Problem'' (TAP) se zaměřuje na dopady teorie her na optimalizaci toku, tj. zkoumá vliv více rozhodovatelů na celkové využití sítě. V práci se zaobíráme úlohou TAP s působením náhodných vlivů, k čemuž využíváme metod stochastické a vícestupňové optimalizace. Dále zkoumáme možnosti zlepšení stávajícího využití sítě za rozhodnutí autoritativního rozhodovatele, kterému je umožněn zásah do samotné struktury sítě, k čemuž využíváme víceúrovňové programování.
|
|
|
Selected optimization models in logistics
Málek, Martin ; Pavlas, Martin (referee) ; Popela, Pavel (advisor)
The bachelor thesis focuses on optimization models in logistics, which are solved by linear programming. Theoretical part introduces basic terms of graph theory, optimization, linear programming and network flows. Practical part contains mathematical models, their implementation, and obtained results. Furthermore, real-world application is solved at the end.
|
|
|
Stochastic Optimization of Network Flows
Málek, Martin ; Holešovský, Jan (referee) ; Popela, Pavel (advisor)
Magisterská práce se zabývá stochastickou optimalizací síťových úloh. Teoretická část pokrývá tři témata - teorii grafů, optimalizaci a progressive hedging algoritmus. V rámci optimalizace je hlavní část věnována stochastickému programování a dvoustupňovému programování. Progressing hedging algoritmus zahrnuje také metodu přiřazování scénářů a modifikaci obecného algoritmu na dvou stupňové úlohy. Praktická část je věnována modelům na reálných datech z oblasti svozu odpadu v rámci České republiky. Data poskytl Ústav procesního inženýrství.
|
|
|
Analysis of Captured DNS Traffic
Hmeľár, Jozef ; Kekely, Lukáš (referee) ; Kováčik, Michal (advisor)
This thesis is focused on the analysis of captured DNS traffic. Introduction of this thesis is focused of basic desciption of computer networks , DNS and description of network flows. Then, the work focused on analysis Netflow format, IPFIX and PCAP, the analysis and implementation of tool for analyzing DNS traffic in C++ programming language. The conclusion is devoted to the results of the implemented tools.
|
guest ::
