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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Generátor síťového provozu pro testování klasifikačních algoritmů / Network Traffic Generator for Testing of Packet Classification Algorithms

Janeček, David January 2020 (has links)
Pokrok při zdokonalování klasifikačních algoritmů je zpomalován nedostatkem dat potřebných pro testování. Reálná data je obtížné získat z důvodu bezpečnosti a ochrany citlivých informací. Existují však generátory syntetických sad pravidel, jako například ClassBench-ng. K vyhodnocení správného fungování, propustnosti, spotřeby energie a dalších vlastností klasifikačních algoritmů je zapotřebí také vhodný síťový provoz. Tématem této práce je tvorba takového generátoru síťového provozu, který by umožnil testování těchto vlastností v kombinaci s IPv4, IPv6 a OpenFlow1.0 pravidly vygenerovanými ClassBench-ng. Práce se zabývá různými způsoby, jak toho dosáhnout, které vedly k vytvoření několika verzí generátoru. Vlastnosti jednotlivých verzí byly zkoumány řadou experimentů. Implementace byla provedena pomocí jazyku Python. Nejvýznamnějším výsledkem je generátor, který využívá principů několika zkoumaných přístupů k dosažení co nejlepších vlastností. Dalším přínosem je nástroj, který bylo nutné vytvořit pro analýzu užitých sad klasifikačních pravidel a vyhodnocení vlastností vygenerovaného síťového provozu.
12

A model for simulation and generation of surrounding vehicles in driving simulators

Olstam, Johan January 2005 (has links)
Driving simulators are used to conduct experiments on for example driver behavior, road design, and vehicle characteristics. The results of the experiments often depend on the traffic conditions. One example is the evaluation of cellular phones and how they affect driving behavior. It is clear that the ability to use phones when driving depends on traffic intensity and composition, and that realistic experiments in driving simulators therefore has to include surrounding traffic. This thesis describes a model that generates and simulates surrounding vehicles for a driving simulator. The proposed model generates a traffic stream, corresponding to a given target flow and simulates realistic interactions between vehicles. The model is built on established techniques for time-driven microscopic simulation of traffic and uses an approach of only simulating the closest neighborhood of the driving simulator vehicle. In our model this closest neighborhood is divided into one inner region and two outer regions. Vehicles in the inner region are simulated according to advanced behavioral models while vehicles in the outer regions are updated according to a less time-consuming model. The presented work includes a new framework for generating and simulating vehicles within a moving area. It also includes the development of enhanced models for car-following and overtaking and a simple mesoscopic traffic model. The developed model has been integrated and tested within the VTI Driving simulator III. A driving simulator experiment has been performed in order to check if the participants observe the behavior of the simulated vehicles as realistic or not. The results were promising but they also indicated that enhancements could be made. The model has also been validated on the number of vehicles that catches up with the driving simulator vehicle and vice versa. The agreement is good for active and passive catch-ups on rural roads and for passive catch-ups on freeways, but less good for active catch-ups on freeways.
13

Accurate Traffic Generation in the CheesePi Network

Sharma, Sagar January 2016 (has links)
Generating traffic to characterize large capacity network links with high accuracy in transport backbones is important for Internet service providers. Using a network application (Iperf) to measure throughput (and indirectly congestion) on links within a network can be used to perform traffic engineering. Using short bursts at high utilisation can ascertain whether a connection can support capacity sensitive applications, such as video streaming. Repeating the process to capture day-night effects can categorise links for management decisions. CheesePi is an Internet quality monitoring system that aims to characterise the services obtained from the home Internet connections of the users and establish an open measurement infrastructure in Sweden. The thesis evaluates a study of performance and characterization of network links within the CheesePi network at high data rates (Gbits/sec) and will extend the work done in the CheesePi software base. / Att kunna generera trafik för karakterisering av stora nätförbindensler med hög noggrannhet är en mycket viktigt faktor för internetleverantörer. Med hjälp av en nätverksapplikation (Iperf) så kan man mäta bithastigheten samt den indirekta överbelastningen på länkar i ett nätverk. Man kan även mäta performansen av nätet för ytterligare analys. Genom att ha intensiv trafik i korta perioder så kan man få ett hum om en uppkoppling kan stödja kapacitets känsliga applikationer så som videouppspelning. I och med att internet användningen varierar så kan man även kategorisera länkarna ytterligare så som dag och natt performansen. CheesePi är ett övervakningssystem som försäkrar kvaliteten och karakteriserarde tjänster som erhållits för hemanslutningar samt infrastrukturs mätningar i Sverige. Examensarbetet utvärderar prestandan och karakteriseringen av nätförbindelser med hög datahastighet (Gigabit/sec) igenom att använda CheesePi programvaran.
14

Contribuições à geração de tráfego fractal por meio da transformada wavelet. / Constributions for fractal traffic generation by wavelest transform.

Lund, Isabelle Reis 26 June 2008 (has links)
Estudos mostraram que o tráfego nas redes de dados tanto locais quanto de grande área, possui propriedades fractais como dependência de longa duração - Long-Range Dependence (LRD) e auto-similaridade. Devido à heterogeneidade de aplicações nessas redes, os traces de tráfego podem apresentar dependência de longa duração - Long Range Dependence (LRD), dependência de curta duração - Short Range Dependence (SRD) ou uma mistura de LRD com SRD. Sendo assim, este trabalho tem como objetivo sintetizar séries temporais gaussianas com flexibilidade de processamento no plano tempo-frequência a serem inseridas num gerador de tráfego com as características estatísticas específicas do tráfego encontrado em redes por comutação de pacotes reais, como autossimilaridade, LRD e SRD. Para isto foram desenvolvidos dois métodos para síntese de séries temporais gaussianas com LRD e simultânea introdução de SRD em diferentes faixas de frequência: Discrete Wavelet Tansform (DWT) com mapa de variâncias e Discrete Wavelet Packet Tansform (DWPT). Estes métodos utilizaram o mapa de variâncias cujo conceito foi desenvolvido neste trabalho. A validação dos métodos foi feita através de análise estatística e comparação com resultados de séries geradas pelo método Discrete Wavelet Transfom (DWT) de Backar utilizado em [1]. Além disso, também foi validada a ideia de que a DWPT é mais interessante que a DWT por ser mais flexível e prover uma maior flexibilidade de processamento no plano tempo-frequência. / Studies demonstrated that the data network traffic of Local Area Network (LAN) and Wide Area Network has fractal properties as long range dependence (LRD) and self-similarity. The traffic traces can show long range dependence, short range dependence or the both behaviors because of applications heterogeneity in these networks. This work objective is to synthetisize gaussian time series with processor flexibility in the time-frequency plan to be inserted in a traffic generator with the specific statistical traffic characteristics of real packet networks such as selfsimilarity, long range dependence (LRD) and short range dependence (SRD). Two methods were developed for the gaussian time series with LRD and SRD synthesis: Discrete Wavelet Tansform (DWT) with variance map and Discrete Wavelet Packet Tansform (DWPT). These methods used the variance map which concept was developed in this work. The methods validation was done by statistic analysis and comparison with the time series generated by the B¨ackar Discrete Wavelet Transfom (DWT) used by [1]. Besides of this, the idea that the DWPT is more because of its processing flexibility in the time-frequency plan was validated.
15

Contribuições à geração de tráfego fractal por meio da transformada wavelet. / Constributions for fractal traffic generation by wavelest transform.

Isabelle Reis Lund 26 June 2008 (has links)
Estudos mostraram que o tráfego nas redes de dados tanto locais quanto de grande área, possui propriedades fractais como dependência de longa duração - Long-Range Dependence (LRD) e auto-similaridade. Devido à heterogeneidade de aplicações nessas redes, os traces de tráfego podem apresentar dependência de longa duração - Long Range Dependence (LRD), dependência de curta duração - Short Range Dependence (SRD) ou uma mistura de LRD com SRD. Sendo assim, este trabalho tem como objetivo sintetizar séries temporais gaussianas com flexibilidade de processamento no plano tempo-frequência a serem inseridas num gerador de tráfego com as características estatísticas específicas do tráfego encontrado em redes por comutação de pacotes reais, como autossimilaridade, LRD e SRD. Para isto foram desenvolvidos dois métodos para síntese de séries temporais gaussianas com LRD e simultânea introdução de SRD em diferentes faixas de frequência: Discrete Wavelet Tansform (DWT) com mapa de variâncias e Discrete Wavelet Packet Tansform (DWPT). Estes métodos utilizaram o mapa de variâncias cujo conceito foi desenvolvido neste trabalho. A validação dos métodos foi feita através de análise estatística e comparação com resultados de séries geradas pelo método Discrete Wavelet Transfom (DWT) de Backar utilizado em [1]. Além disso, também foi validada a ideia de que a DWPT é mais interessante que a DWT por ser mais flexível e prover uma maior flexibilidade de processamento no plano tempo-frequência. / Studies demonstrated that the data network traffic of Local Area Network (LAN) and Wide Area Network has fractal properties as long range dependence (LRD) and self-similarity. The traffic traces can show long range dependence, short range dependence or the both behaviors because of applications heterogeneity in these networks. This work objective is to synthetisize gaussian time series with processor flexibility in the time-frequency plan to be inserted in a traffic generator with the specific statistical traffic characteristics of real packet networks such as selfsimilarity, long range dependence (LRD) and short range dependence (SRD). Two methods were developed for the gaussian time series with LRD and SRD synthesis: Discrete Wavelet Tansform (DWT) with variance map and Discrete Wavelet Packet Tansform (DWPT). These methods used the variance map which concept was developed in this work. The methods validation was done by statistic analysis and comparison with the time series generated by the B¨ackar Discrete Wavelet Transfom (DWT) used by [1]. Besides of this, the idea that the DWPT is more because of its processing flexibility in the time-frequency plan was validated.
16

Verkehrsnachfragemodellierung am Beispiel der Stadt Brandenburg an der Havel

Schwarz, Matthias 26 March 2018 (has links) (PDF)
Das Thema der vorliegenden Bachelorarbeit ist, das Vier-Stufen-Modell der Verkehrsnachfrage nach Lohse, auch als Kennwertmodell bekannt, auf die Stadt Brandenburg an der Havel anzuwenden, um die Verkehrserzeugung, die Verkehrsverteilung und die Verkehrsmittelwahl zu berechnen. Dies ist für alle Leser interessant, die damit beginnen, sich mit der integrierten Verkehrsplanung zu beschäftigen, denn diese Arbeit stellt das theoretische, rechnerische und praktische Vorgehen formal vor. Die Berechnungen wurden mit dem Programm „Excel 2013“ realisiert. Zudem ist der Arbeit ein USB-Stick beigelegt, aus dem Sie die formalen Rechnungen aus der Bachelorarbeit besser nachvollziehen können, da auf dem USB-Stick alle Rechnungen hinterlegt sind, die dem Verfahren zugrunde liegen. Zusätzlich enthält der USB-Stick einige Grafiken, welche die Verteilung der Verkehrsmittel in der Stadt Brandenburg an der Havel darstellen.
17

Verkehrsnachfragemodellierung am Beispiel der Stadt Brandenburg an der Havel

Schwarz, Matthias 12 February 2018 (has links)
Das Thema der vorliegenden Bachelorarbeit ist, das Vier-Stufen-Modell der Verkehrsnachfrage nach Lohse, auch als Kennwertmodell bekannt, auf die Stadt Brandenburg an der Havel anzuwenden, um die Verkehrserzeugung, die Verkehrsverteilung und die Verkehrsmittelwahl zu berechnen. Dies ist für alle Leser interessant, die damit beginnen, sich mit der integrierten Verkehrsplanung zu beschäftigen, denn diese Arbeit stellt das theoretische, rechnerische und praktische Vorgehen formal vor. Die Berechnungen wurden mit dem Programm „Excel 2013“ realisiert. Zudem ist der Arbeit ein USB-Stick beigelegt, aus dem Sie die formalen Rechnungen aus der Bachelorarbeit besser nachvollziehen können, da auf dem USB-Stick alle Rechnungen hinterlegt sind, die dem Verfahren zugrunde liegen. Zusätzlich enthält der USB-Stick einige Grafiken, welche die Verteilung der Verkehrsmittel in der Stadt Brandenburg an der Havel darstellen.
18

Shopping center e seus impactos na circulação urbana. Estudo de caso: Center Shopping em Uberlândia, MG / Shopping center and its impacts in the urban circulation. Study of case: Center shopping, Uberlândia, MG

Andrade, Caroline Pongitori Soares de 24 August 2005 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The work, however displayed, comes to present a reflection about spaces of the city in the scope of the planning of the urban areas, specifically in the existing relation between the use of the land and the road system and of transports. The objective is to evaluate the reciprocity between these planning instances that they search to organize the city in its peculiarities, but that they must present a mutuality relation. The target of the work consists of the evaluation of an enterprise of great size, situated in the city of Uberlândia, Minas Gerais, with potential to generate interferences of great impact in its area of insertion as much in environmental terms as in the urban circulation that, in turn, also intervenes in the urban environment. It is reality of the great and medium urban centers the problems with congestion, traffic accidents, sonorous, visual and urban pollution what it generates, loses of time, energy, productivity and human resources. Of this form, great enterprises cause impacts in the transport system, in the immediate road system and in the neighborhoods it relative to its demand and, consequently, how much it offers of these infrastructures. The amplitude of the subject allows that it is opened to some questionings, being able to be explored by several meanings. Here, it will be argue, in specific, about the urban circulation and the systems of transport. One adopted methodologies proposals for Goldner, in 1994, exclusively, treating to shopping centers; of the Company of Engineering of Traffic CET, in 1983, and the National Department of Transports DENATRAN, 2001. For elaboration of the work and confirmation of the hypothesis above, it had been necessary data that characterize study area, about the city, the place of implantation of the enterprise and to the systems of transport and legislation about traffic generation and studies of impacts. It carried research in the place that allowed the characterization of the public of shopping and the attracted trips. The study of the variables that had contributed for the attraction of trips, the distribution of these displacements and the capacity of the road system, this last one, before and after implantation of shopping, they had also been analysis objects. The quantitative studies had been carried through by statistical calculation and of the software aaSidra 2.0. Of this form, one searched to contribute for the reflection about the necessity of studies of the use of the ground in the perspective of the urban circulation during the intervention in the city and the elaboration and quantification of interferences by studies of environmental and neighborhood impact. / O trabalho, ora exposto, vem apresentar uma reflexão sobre os espaços da cidade no âmbito do planejamento de áreas urbanas, especificamente na relação existente entre o uso do solo e o sistema viário e de transportes. O objetivo é avaliar a reciprocidade entre estas instâncias de planejamento que visam organizar a cidade em suas especificidades, mas que devem apresentar uma relação de mutualidade. O escopo do trabalho consiste na avaliação de um empreendimento de grande porte, situado na cidade de Uberlândia, Minas Gerais, com potencial de gerar interferências de grande impacto na sua área de inserção, tanto em termos ambientais como na circulação urbana que, por sua vez, também interfere no ambiente urbano. É realidade dos grandes e médios centros urbanos os problemas com congestionamento, acidentes de trânsito, poluição sonora, visual e do ar o que gera, perdas de tempo, energia, produtividade e recursos humanos. Assim, grandes empreendimentos são potenciais causadores de impactos no sistema de transporte, no sistema viário imediato e nas proximidades devido à sua demanda frente à oferta dessas infra-estruturas. A amplitude do assunto é passível de vários questionamentos, podendo ser explorado por meio de diversos vieses. Aqui foi avaliado, em específico, a circulação urbana e o sistema de transporte. Adotou-se metodologia proposta por Goldner, em 1994, tratando exclusivament e de shopping centers; da Companhia de Engenharia de Tráfego CET, de 1983 e do Departamento Nacional de Trânsito DENATRAN, em 2001. Para a elaboração do trabalho e confirmação da hipótese levantada, foram necessários dados que caracterizassem a área de estudo, no que se refere à cidade, ao local de implantação do empreendimento e aos sistemas de transporte, bem como legislação referente a Pólos Geradores de Tráfego e Estudos de Impacto. Realizou se pesquisa no local que permitiu a caracterização do púb lico do shopping e das viagens atraídas. O estudo das variáveis que contribuem para a geração de viagens ; a distribuição dos deslocamentos e a capacidade do sistema viário; essa última, antes e após implantação do shopping, também foram objetos de análise. Os estudos quantitativos foram realizados por meio de cálculo estatístico e do programa de avaliação aaSidra 2.0. Desta forma, buscou-se contribuir para a reflexão sobre a necessidade de estudos sobre o uso do solo na perspectiva da circulação urbana quando da intervenção na cidade e da avaliação e quantificação de interferências por meio de estudos de impacto ambiental e de vizinhança. / Mestre em Engenharia Civil

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