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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.
161

Lecture acoustique de la voie ferrée / Acoustic reading of railway track

Chartrain, Pierre-Emile 17 October 2013 (has links)
Le bruit de roulement est la principale source de bruit des transports ferroviaires pour des vitesses conventionnelles. Il est produit par les vibrations puis le rayonnement acoustique du matériel roulant et de la voie provoqués par le déplacement de la roue et du rail. Ce déplacement est imposé par les défauts microscopiques de surface présents sur les bandes de roulement appelés rugosité.La directive Européenne 2002/49/CE exige la réalisation la cartographies du bruit des infrastructures de transport. Le bruit dans l’environnement peut être prédit par des modèles dont les paramètres d’entrées sont notamment le comportement dynamique de la voie et la rugosité des rails. Ces données sont généralement évaluées par des systèmes de mesures statiques, ce qui limite la caractérisation de la voie à quelques dizaines ou centaines de mètres.Cette thèse a pour objectif de proposer et de valider une méthodologie de mesure de l'état acoustique de la voie sur l’ensemble du réseau. La solution proposée est un système de mesure en situation embarquée nommé LECAV pour « LECture Acoustique de la Voie », qui utilise le bruit rayonné par la voir et par la roue. Leurs gammes de fréquences de rayonnement distinctes permettent de traiter le problème inverse séparément pour la roue et pour le rail, et ceux à partir de l’impédance acoustique.Un modèle vibroacoustique basé sur la méthode des éléments finis et la formulation intégrale de Rayleigh est proposé afin d’estimer l’impédance acoustique de la roue. Pour le rail, les théories des poutres épaisses et des sources ponctuelles élémentaires sont utilisées dans le but de modéliser son impédance acoustique. / The rolling noise is the main source of noise in the railway transport sector at conventional speed. It is produced by the vibration and the acoustic radiation of the vehicle and the railway track, caused by the movement of at the wheel and the rail. These movements are imposed by microscopic irregularities on the rolling surface called roughness.The 2002/49/EC European directive imposes to build noise maps of transport infrastructure. The noise propagating in the environment can be assessed from models whose input parameters are particularly the dynamic behavior of railway tracks and the roughness of rails. These data are generally measured thanks to static systems, which narrow down to the analysis of railway tracks to a few meters.The aim of this Phd is to propose and validate a measurement methodology for the acoustic characterization of tracks for the whole railway network. It is an on-board measurement system named LECAV for "LECture Acoustique de la Voie" in French ("Acoustic reading of railway track") that uses the noise radiated from the wheel and the rail. The respective frequencies ranges of noise emission allow solving the invers problem separately for the wheel and for the rail, and this with the acoustic impedance.
162

Vysokorychlostní a rychlá železniční přeprava osob v Evropě se zaměřením na středoevropský region / High-speed passenger rail transport in Europe with a focus on the Central European region

Bartoňová, Lucie January 2012 (has links)
Diploma thesis focuses on the development of high-speed passenger rail in Europe and studies possible geographic expansion of these lines and their feasibility. The theoretical part deals with the development of high-speed rail transport in Europe-especially in France, Italy, Germany and the Iberian Peninsula. In the practical part the thesis analyzes the present spatial expansion possibilities of high speed rail (HSR) with regard to international routes. In the conclusion is in the diploma thesis drafted HSR network for the Central European region.
163

Kombinovaná přeprava v podmínkách společnosti PELMI s.r.o. / Combined Transport in conditions of PELMI, Ltd.

Kuncová, Andrea January 2013 (has links)
The thesis is divided into two parts. The first theoretical part defines the basic concepts related to combined transport and its current trends and supporting projects. It is focused on the structure of the European transport networks, with emphasis on road and rail transport. The practical part was developed in collaboration with the company PELMI, Ltd. and is focused on the analysis of the current situation of combined transport and price comparison of straight road and combined transport of containers. There is evaluation and definition of the conditions in which is advantageous / disadvantageous to move the containers road carriage to continental combined transport involving rail in conclusion.
164

Vysokorychlostní železniční doprava v Asii / High-speed rail system in Asia

Švarc, Michal January 2015 (has links)
The Master Thesis focuses on comprehensive evaluation of high-speed rail in Japan. The theoretical part describes the history of the Shinkansen systém, which is currently the standard of the high-speed rail. It also discusses the analysis of the key technologies, support systems and respect for nature. Within the technology part also represents a MAGLEV technology, currently being developer as a succesor to the high-speed traffic. In the analytical part analyzes in detail the different tracks and trains used on them. Finally the author compares the Shinkansen system compared to other modes of public transport and passenger transport in three different length routes.
165

Vysokorychlostní železnice ve Francii se zaměřením na nízkonákladové společnosti / High-speed rail in France within the scope of low cost railway companies

Musil, Jaroslav January 2015 (has links)
The Master Thesis focuses on development of high-speed rail in France within the scope of low-cost rail companies. The theoretical part describes the process of formation and development of French railways since the beginning of 19th century. It also discusses reasons leading to the creation of high-speed rail and different rail routes and also organizational structure of the company SNCF. Within analytical part, it describes researched types of transport and different groups of passengers. In the last part of the paper, with a help of multicriterial analyses, the most suitable type of transport on a certain route for each group of passengers is chosen.
166

Železničná doprava v USA / Rail transport in the United States

Bódi, Andrej January 2012 (has links)
This Master Thesis focuses on the American railroads as a whole. It describes the evolution of the railroads and the on-going transformation of its importance in comparison with other means of transport. Further, there are described 5 major railway companies and the state owned company Amtrak, which focuses on passenger transport. The analysis elaborates on the topic of competitivness of Amtrak in various corridors. The author is seeking the answer to the question: Is there a possible gap in the passenger transport market that Amtrak can fill?
167

Liberalizace železniční dopravy v České republice, srovnání železničních dopravců v relaci Praha - Ostrava / Liberalization of rail transport in the Czech Republic and comparison of the railway carriers in the transport session Prague - Ostrava

Šafránek, Radek January 2014 (has links)
The aim of this diploma thesis is a summary of current knowledge and experience and analysis of the development of liberalization of the rail passenger transport in the Czech Republic and a detailed description of the current situation and comparison with the transport session Prague - Ostrava, where 3 railway carriers are competing for the favour of passengers. In the first part of the thesis is described historical development of the railways in the world and in the Czech Republic. The following section discusses the legislation relating to rail transport and its liberalization, both from the perspective European as well as from the Czech. The widest third part shows efforts, which have already taken place for tenders for the operation of railway transport and the steps that led to this state. The final part deals with the situation of the rail transport in the transport session Prague - Ostrava, where, as a single line in the Czech Republic, competition among rail carriers was launched.
168

Konstrukce podvozku pro dvounápravový motorový železniční vůz / Two Axle Railcar Suspension Design

Polcer, Pavel January 2018 (has links)
This thesis contains a design for two axle railcar suspension. Functionality of the design was verified using analytical and numerical calculations.
169

Dopady rozhodnutí vlády o zásahu do cenové tvorby jízdného v rámci osobní železniční dopravy, komparace ČR a SR / Impacts of the government´s decision to intervene in fare pricing policies within passenger railway transportation. Comparison between Czech and Slovak markets.

Lofaj, Jakub January 2019 (has links)
The subject of the diploma´s thesis is the comparison of the particular private rail transport policies in the Czech Republic and Slovakia. There are specific, both economic and non-economic impacts of a free fare in Slovakia and slightly different policy of fare discounts in the Czech Republic, identified and consequently analyzed in the thesis. Comparative analysis between both policies is conducted right after. All the impacts are measured and evaluated in the context of particular government budgets, both national and private railway transporters and different segments of users, who are mostly affected by the movement. The analysis of these extraordinary government policies is conducted based on selected publicly available indicators and data from several different sources (official statistics, agreements, annual reports, tariffs comparison, financial statements, granted subsidies etc.).
170

Optimalizace rozhraní svařovaného zásobníku paliva systému common rail / Interface Optimization of Welded Fuel Accumulator of Common Rail System

Hurt, Libor January 2009 (has links)
This master’s thesis is aimed to sphere of injection system for diesel engines. The main task of thesis was to invent new concept for high pressure interface of laser welded fuel accumulator, that would able to endure pressure 2000 bars and higher. Also, it would be applicable to serial production. Thesis includes description of diesel system by Bosch, making of design proposals in ProEngineer program and making of stress analyses for some particular elements in Ansys. Whole the work was passed in conjunction with Bosch Diesel development department.

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