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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

Projetos de estruturas lineares: o transporte e suas trilhas e os caminhos da energia - os limites da sustentabilidade / Linear structures projects: transport roads and energy trails - sustentainability limits

Claudio, Celina Franco Bragança Rosa 08 April 2008 (has links)
O assunto básico da pesquisa, como o titulo selecionado, refere-se às estruturas lineares e às faixas necessárias para sua implantação como as linhas de infra-estrutura de rodovias e demais modais de transporte, bem como a infra-estrutura de energia realizada por meio de dutos e linhas de transmissão. As partes da pesquisa selecionadas para a Tese fazem referência aos módulos que serão desenvolvidos, a saber: Primeiro Módulo: Trata dos antecedentes do projeto de pesquisa e da natureza da tipologia de infra-estrutura das estruturas lineares que estão inseridas nas malhas viárias e nas redes de energia. Segundo Módulo: A Cidade Linear sob o olhar da natureza do percurso das águas e da natureza do percurso da energia. A Ocupação de São Paulo, desde a procura do sítio sustentado, o ambiente natural, até a ocupação metropolitana. O sistema de transportes desenhando o ambiente construído até a esfera regional. Terceiro Módulo: A Avaliação de Impacto Ambiental AIA na implantação de projetos de estruturas lineares, com base no conceito de impacto ambiental e as metodologias adotadas para sua quali e quantificação. Quarto Módulo: As Formas de Participação Pública são discutidas visando apontar os benefícios de seu procedimento. A participação pública no Processo de Avaliação do Projeto por meio de Técnicas de Comunicação e Audiências Públicas entre outras. Quinto Módulo: Como considerações finais os casos de empreendimentos lineares apresentados na Região Metropolitana de São Paulo são classificados de forma a buscar alternativas para futuros empreendimentos de mesma natureza. O modelo proposto para avaliação de projeto é objeto de analise. O desenvolvimento da infra-estrutura, de rodovias, ferrovias, linhas de transmissão e dutovias, estão inseridos em segmentos de redes ou malhas de energia ou transportes, as quais deverão se apropriar de corredores de grandes extensões em território que deverá ser avaliado de forma sustentável. / The research´s main subject, as seen in the title, Linear Structure Projects: Transport roads and energy trails sustentainable limits, refers to the linear structures and the lanes that are needed to its implantation like the roads structure lanes and also different kinds of transportation, transmission energy lines and pipelines. The researchs extracts selected to the Thesis, make references to the chapters that are going to be developed they are: Chapter one: Research projects previous considerations were analyzed as well as the linear structures types that are inside of all transportation and energy net. Chapter two: The linear city under the eyes of the water and energy nature course. São Paulo`s territorial occupation, since the search of sustainable place, the natural environment, until metropolitan occupation.The transport system drawing the built environment until the regional boundary. Chapter three: The Environmental Impact Assessment EIA on the implantation of linear structures projects, with basis on environmental impact concepts and suitable methodologies for quality and quantity evaluation. Chapter four: The ways of public participation are discussed aiming the benefits of its procedure. Public participation on the projects analysis process through communication techniques and public hearings among others. Chapter five: Come to conclusion after analyzing the select cases on São Paulo`s metropolitan area, alternatives were brought to discussion for a new future construction with same typologies of linear structures. A new model of project evaluation is presented. The segments of transport and energy nets must be evaluated with sustainable basis.
162

As primeiras concessões ferroviárias na Argentina e no Brasil: análise comparativa da evolução e desempenho de quantro empresas, 1850-1888 / The first railway concessions in Argentina and Brazil: a comparative analysis of the evolution and performance of four companies, 1850-1888

Albuquerque, Caio Junqueira de Souza 28 April 2015 (has links)
As ferrovias desempenharam um papel fundamental na transformação econômica pela qual passaram a Argentina e o Brasil, na segunda metade do século XIX. Estes países adotaram um modelo agroexportador, a fim de se inserirem na economia internacional que se desenvolvia à época. Milhares de quilômetro de trilhos foram construídos em cada país, boa parte deles por particulares, que recebiam concessões dos governos argentino e brasileiro tanto nacionais quanto provinciais. Para promover a construção de trilhos em países que, até meados do século XIX, se encontravam praticamente às margens da economia mundial e que não tinham qualquer tradição ferroviária, os governos precisaram outorgar uma série de benefícios a particulares, de modo a tornar as concessões atrativas. O objetivo deste trabalho é investigar os contratos e as condições das primeiras concessões ferroviárias de quatro estradas de ferro construídas na Argentina e no Brasil: o Ferrocarril Central Argentino, o Ferrocarril del Sud, a Companhia Paulista de Estradas de Ferro e a Companhia Mogiana de Estradas de Ferro. Essas ferrovias se instalaram em regiões importantes para o complexo agroexportador que se desenvolveu em ambos os países. Além do estudo de suas concessões, também se analisou o desempenho das companhias em apreço, entre 1880 e 1888. As principais fontes deste trabalho são (i) as próprias concessões ferroviárias, (ii) documentos normativos argentinos e brasileiros sobre estradas de ferro, (iii) os relatórios dos diretores aos acionistas das empresas estudadas e (iv) revistas do século XIX sobre ferrovias. Os benefícios outorgados a investidores foram importantes para a promoção das primeiras estradas de ferro na Argentina e no Brasil. A garantia de juros foi o principal deles e ajudou a tornar as concessões desses dois países atrativas, visto que tal benefício era utilizado por diversos países. Contudo, a garantia de juros foi, frequentemente, concedida de maneira não criteriosa assim como outros benefícios outorgados pelos governos. Muitas das críticas que podem ser feitas à outorga de benefícios nas concessões questionam não os benefícios per se, mas o modo com que eles foram concedidos e, posteriormente, regulados. Se, por um lado, sustentou algumas estradas de ferro que não se revelaram lucrativas, a garantia de juros também conseguiu promover ferrovias rentáveis, que se tornaram independentes desse subsídio e ajudaram a desenvolver a economia do país em que se inseriam. É o caso das quatro companhias estudadas: todas elas se revelaram lucrativas na década de 1880, apesar das diferenças existentes entre elas em diversos aspectos como extensão, diferenças na colonização da região em / Railways have performed a significant role on the Argentine and Brazilian economic development during the second half of nineteenth century. These countries have adopted an agro-export economic model, with the purpose of deepening their ties with the international economy that was being developed. Thousands of kilometers of rails were built in each country. A good amount of them by privates, who were granted a concession from Argentine and Brazilian Governments both national and provincial. In order to build rails in countries that were, during mid-nineteenth century, loosely linked with the worlds economy and lacking railways, the governments had to bestow benefits to privates, to make concessions more attractive. This study aims to investigate the conditions and the contracts of the first railway concessions of four Argentine and Brazilian companies: the Central Argentine Railway Company, the Buenos Aires Great Southern Railway Company, the Companhia Paulista de Estradas de Ferro and the Companhia Mogiana de Estradas de Ferro. These companies were established in regions in which the agro-export model has developed. In addition to the study of the concessions, the companies performance was also analyzed. The main sources of this work are: (i) the railways concessions; (ii) normative documents about railways in Argentina and Brazil; (iii) report of the directors to shareholders of the analyzed companies; and (iv) railway magazines from the nineteenth century. The privileges conceded to investors were important to promote the first railways in Argentina and Brazil. A guarantee of interest was the main privilege given in order to render the concessions attractive, as this benefit was also bestowed by different countries. However, the guarantee of interest was, oftenly, given in a non careful manner as other benefits conceded by the government. Many of the criticisms related to the grant of benefits in concessions question not the benefits per se, but the way they were bestowed and, afterwards, regulated. If, on one hand, the guarantee of interest has sustained unprofitable railways, it has also had the ability to promote lucrative railways, that have become free of this subsidy and have developed their own national economy. It is the case of the four investigated companies: they have revealed themselves profitable during the 1880s, despite the differences that distinguished them: extension, differences at the colonization of the regions in which they were built, gauge, passenger and good carried, among others.
163

Oscar Bardi De Fourtou (1836-1897) : un ministre contre la République / Oscar Bardi de Fourtou (1836-1897) : a minister against the Republic

Truel, Thierry 08 February 2014 (has links)
Oscar Bardi de Fourtou est entré dans l’histoire de la vie politique française comme l’Homme du Seize-Mai, ministre de l’Intérieur à poigne, qui ne laisse pas de place à la contestation de ses décisions que l’urgence d’une crise commande. Chargé par le maréchal de Mac-Mahon de mener une lutte contre les républicains, il procède à d’importants mouvements de fonctionnaires afin que l’action gouvernementale soit soutenue localement par des agents fidèles et dévoués. Avec la dissolution de la Chambre des députés en juin 1877, il est chargé de préparer les élections législatives et empêcher les républicains de les gagner. Tous les moyens légaux sont utilisés mais soumis à la pression des différentes composantes de l’alliance conservatrice qui soutiennent l’initiative présidentielle. L’échec électoral provoque la responsabilité évidente d’un ministre trop exposé pendant la crise. Cette condamnation des vainqueurs est aussi perceptible dans les rangs de la droite conservatrice, déçue que Fourtou n’ait pris de résolutions plus radicales. Sa carrière politique est fulgurante. Avocat au barreau de Ribérac, puis maire de la ville, il est élu député de la Dordogne à trente-six ans en février 1871. Inscrit au centre-droit, il se fait remarquer par Thiers qui le nomme ministre des Travaux Publics. Après la chute du président de la République, il se rapproche de la droite dynastique et obtient la confiance de Mac-Mahon qui lui confie le ministère de l’Instruction publique, des Cultes et des Beaux-Arts. Il incarne alors une expression autoritaire du pouvoir qui est en partie la raison de sa nomination place Beauvau en juin 1874 et à nouveau en mai 1877. Parallèlement à cette carrière ministérielle, il poursuit son ancrage local (président de comice agricole, conseiller général) et devient administrateur de la Compagnie de chemin de fer d’Orléans. Fourtou est alors l’une des figures importantes de la droite conservatrice, proche de l’Elysée. Après le Seize-Mai, il poursuit sa carrière politique, malgré la flétrissure et l’invalidation de son élection qui le conduit à se représenter immédiatement et obtenir la confiance de la population. Devenu sénateur, il continue la lutte contre les réformes des opportunistes mais échoue aux différents scrutins nationaux de 1885. A la faveur du boulangisme, il redevient député en 1889 mais propose de jouer la carte de l’apaisement, signe d’une évolution idéologique de l’homme politique. Parlementaire au parcours singulier, il représente, avec d’autres, les interrogations et la recherche identitaire d’une droite française en pleine transformation dans les premières années de la Troisième République. La postérité ne retient, finalement, que la légende noire de l’ancien ministre de l’Intérieur du Seize-Mai. / Oscar Bardi de Fourtou is involved in french political life as the Man of the Seize-Mai, the Home minister with a very special manner leading with authority and his decisions don’t accept any protest. Commissioned by the marechal Mac-Mahon to lead the fight against republicans, he organized a lot of changes inside the civil servant corps, to help the government restore its power in local position. With the dissolution of the Parliament, he had to prepare the next legislative elections in October 1877 to prevent the victory of republicans. All the legal means were used but under the political pressure of the different components of the Conservative forces which maintain the President policy. The electoral failure of the Conservative forces involved the political responsibility of the former Home minister. His bad reputation came from the winner and also in the Conservative camp, disappointed by his attitude during the crisis not taking strong solutions to resolve it. His political career is lightning. As a lawyer in Riberac, and mayor of his home town, he was elected as Member of Parliament on February 1871. Registered as a member of Right Center, he was chosen by Thiers to be the new Public Work of his government. After the of the President, he was closer to the dynastic Right, and got confidence of the new President Mac-Mahon who decided to give him the Public Education ministry. Therefore, Fourtou represents the authoritarian position of one part of the Conservatives and that’s the reason he changed to the Home ministry in June 1874 and of course, in May 1877.At the same time, he continues his local work and became the Orleans railways Company manager. One of the most important politicians of the French Right, he was closely linked to the Elysee palace. After the Seize-Mai, he carried on his political business, despite the stigmatization of the Parliament, and his invalidation, he was elected again. As senator, he fought against the opportunist reforms but didn’t succeed in the different national elections in 1885. Thanks to the Boulanger crisis, he again became a Member of Parliament in 1889 but wants to promote appeasement, as underlined in evidence in his ideological evolution. As a singular Member of Parliament, he represented a new position, with other colleagues, into the Right movement., especially the search for a new French Right identity during important changes in the first years of the Third Republic. In front of the posterity, with hindsight, he remains a dark legend as the Home minister of the Seize-Mai.
164

Projetos de estruturas lineares: o transporte e suas trilhas e os caminhos da energia - os limites da sustentabilidade / Linear structures projects: transport roads and energy trails - sustentainability limits

Celina Franco Bragança Rosa Claudio 08 April 2008 (has links)
O assunto básico da pesquisa, como o titulo selecionado, refere-se às estruturas lineares e às faixas necessárias para sua implantação como as linhas de infra-estrutura de rodovias e demais modais de transporte, bem como a infra-estrutura de energia realizada por meio de dutos e linhas de transmissão. As partes da pesquisa selecionadas para a Tese fazem referência aos módulos que serão desenvolvidos, a saber: Primeiro Módulo: Trata dos antecedentes do projeto de pesquisa e da natureza da tipologia de infra-estrutura das estruturas lineares que estão inseridas nas malhas viárias e nas redes de energia. Segundo Módulo: A Cidade Linear sob o olhar da natureza do percurso das águas e da natureza do percurso da energia. A Ocupação de São Paulo, desde a procura do sítio sustentado, o ambiente natural, até a ocupação metropolitana. O sistema de transportes desenhando o ambiente construído até a esfera regional. Terceiro Módulo: A Avaliação de Impacto Ambiental AIA na implantação de projetos de estruturas lineares, com base no conceito de impacto ambiental e as metodologias adotadas para sua quali e quantificação. Quarto Módulo: As Formas de Participação Pública são discutidas visando apontar os benefícios de seu procedimento. A participação pública no Processo de Avaliação do Projeto por meio de Técnicas de Comunicação e Audiências Públicas entre outras. Quinto Módulo: Como considerações finais os casos de empreendimentos lineares apresentados na Região Metropolitana de São Paulo são classificados de forma a buscar alternativas para futuros empreendimentos de mesma natureza. O modelo proposto para avaliação de projeto é objeto de analise. O desenvolvimento da infra-estrutura, de rodovias, ferrovias, linhas de transmissão e dutovias, estão inseridos em segmentos de redes ou malhas de energia ou transportes, as quais deverão se apropriar de corredores de grandes extensões em território que deverá ser avaliado de forma sustentável. / The research´s main subject, as seen in the title, Linear Structure Projects: Transport roads and energy trails sustentainable limits, refers to the linear structures and the lanes that are needed to its implantation like the roads structure lanes and also different kinds of transportation, transmission energy lines and pipelines. The researchs extracts selected to the Thesis, make references to the chapters that are going to be developed they are: Chapter one: Research projects previous considerations were analyzed as well as the linear structures types that are inside of all transportation and energy net. Chapter two: The linear city under the eyes of the water and energy nature course. São Paulo`s territorial occupation, since the search of sustainable place, the natural environment, until metropolitan occupation.The transport system drawing the built environment until the regional boundary. Chapter three: The Environmental Impact Assessment EIA on the implantation of linear structures projects, with basis on environmental impact concepts and suitable methodologies for quality and quantity evaluation. Chapter four: The ways of public participation are discussed aiming the benefits of its procedure. Public participation on the projects analysis process through communication techniques and public hearings among others. Chapter five: Come to conclusion after analyzing the select cases on São Paulo`s metropolitan area, alternatives were brought to discussion for a new future construction with same typologies of linear structures. A new model of project evaluation is presented. The segments of transport and energy nets must be evaluated with sustainable basis.
165

La Compagnie des chemins de fer de l'Est : contribution à l'histoire juridique des transports ferroviaires / The French East Railway Company : contribution to the legal history of the rail transport

Rohrbacher, Michel 15 February 2014 (has links)
La Compagnie des chemins de fer de l’Est est une société anonyme ferroviaire créée en 1854. Elle résulte de fusions entre plusieurs compagnies concessionnaires de lignes dans le Nord-Est de la France. La Compagnie de l’Est perd une partie de son réseau à la suite de la guerre franco-allemande de 1870-1871. Elle poursuit néanmoins son existence, jusqu’à la nationalisation des chemins de fer en 1937. La Compagnie des chemins de fer de l’Est se transforme alors en Société d’Investissement de l’Est, détentrice de 17,9% du capital de la Société Nationale des Chemins de fer Français et représentée au conseil d’administration de cette dernière. Cette thèse, axée sur la notion de service public, se propose d’étudier dans un premier temps la Compagnie de l’Est en tant que société commerciale. Ses composantes, son fonctionnement et le statut de son personnel font l’objet d’une attention particulière. Dans un second temps, l’établissement du réseau de l’Est, tout comme son exploitation, sont développés. Les notions de concession, d’expropriation pour cause d’utilité publique, de contrat de transport et de responsabilité sont ici précisées. / The French East Railway Company is a railway public limited company which was founded in 1854. Several statutory railway companies in the North East of France merged into one to create it. The East Company lost a part of its network after the Franco-Prussian war of 1870-1871. However, it continued to exist until the railway nationalization in 1937. The East Railway Company then became the East Investment Trust, with representation on the board of directors of the French National Railway Company, and with shares up to 17,9% of its capital.This thesis, which focuses on the public service, will first examine the East Railway Company as a business firm. Its elements, its working and the status of its workforce will be analyzed. Secondly the creation of the Eastern network and its development will be presented. The concepts of concession, compulsory purchase order, carriage transport contract and liability will be underlined.
166

As primeiras concessões ferroviárias na Argentina e no Brasil: análise comparativa da evolução e desempenho de quantro empresas, 1850-1888 / The first railway concessions in Argentina and Brazil: a comparative analysis of the evolution and performance of four companies, 1850-1888

Caio Junqueira de Souza Albuquerque 28 April 2015 (has links)
As ferrovias desempenharam um papel fundamental na transformação econômica pela qual passaram a Argentina e o Brasil, na segunda metade do século XIX. Estes países adotaram um modelo agroexportador, a fim de se inserirem na economia internacional que se desenvolvia à época. Milhares de quilômetro de trilhos foram construídos em cada país, boa parte deles por particulares, que recebiam concessões dos governos argentino e brasileiro tanto nacionais quanto provinciais. Para promover a construção de trilhos em países que, até meados do século XIX, se encontravam praticamente às margens da economia mundial e que não tinham qualquer tradição ferroviária, os governos precisaram outorgar uma série de benefícios a particulares, de modo a tornar as concessões atrativas. O objetivo deste trabalho é investigar os contratos e as condições das primeiras concessões ferroviárias de quatro estradas de ferro construídas na Argentina e no Brasil: o Ferrocarril Central Argentino, o Ferrocarril del Sud, a Companhia Paulista de Estradas de Ferro e a Companhia Mogiana de Estradas de Ferro. Essas ferrovias se instalaram em regiões importantes para o complexo agroexportador que se desenvolveu em ambos os países. Além do estudo de suas concessões, também se analisou o desempenho das companhias em apreço, entre 1880 e 1888. As principais fontes deste trabalho são (i) as próprias concessões ferroviárias, (ii) documentos normativos argentinos e brasileiros sobre estradas de ferro, (iii) os relatórios dos diretores aos acionistas das empresas estudadas e (iv) revistas do século XIX sobre ferrovias. Os benefícios outorgados a investidores foram importantes para a promoção das primeiras estradas de ferro na Argentina e no Brasil. A garantia de juros foi o principal deles e ajudou a tornar as concessões desses dois países atrativas, visto que tal benefício era utilizado por diversos países. Contudo, a garantia de juros foi, frequentemente, concedida de maneira não criteriosa assim como outros benefícios outorgados pelos governos. Muitas das críticas que podem ser feitas à outorga de benefícios nas concessões questionam não os benefícios per se, mas o modo com que eles foram concedidos e, posteriormente, regulados. Se, por um lado, sustentou algumas estradas de ferro que não se revelaram lucrativas, a garantia de juros também conseguiu promover ferrovias rentáveis, que se tornaram independentes desse subsídio e ajudaram a desenvolver a economia do país em que se inseriam. É o caso das quatro companhias estudadas: todas elas se revelaram lucrativas na década de 1880, apesar das diferenças existentes entre elas em diversos aspectos como extensão, diferenças na colonização da região em / Railways have performed a significant role on the Argentine and Brazilian economic development during the second half of nineteenth century. These countries have adopted an agro-export economic model, with the purpose of deepening their ties with the international economy that was being developed. Thousands of kilometers of rails were built in each country. A good amount of them by privates, who were granted a concession from Argentine and Brazilian Governments both national and provincial. In order to build rails in countries that were, during mid-nineteenth century, loosely linked with the worlds economy and lacking railways, the governments had to bestow benefits to privates, to make concessions more attractive. This study aims to investigate the conditions and the contracts of the first railway concessions of four Argentine and Brazilian companies: the Central Argentine Railway Company, the Buenos Aires Great Southern Railway Company, the Companhia Paulista de Estradas de Ferro and the Companhia Mogiana de Estradas de Ferro. These companies were established in regions in which the agro-export model has developed. In addition to the study of the concessions, the companies performance was also analyzed. The main sources of this work are: (i) the railways concessions; (ii) normative documents about railways in Argentina and Brazil; (iii) report of the directors to shareholders of the analyzed companies; and (iv) railway magazines from the nineteenth century. The privileges conceded to investors were important to promote the first railways in Argentina and Brazil. A guarantee of interest was the main privilege given in order to render the concessions attractive, as this benefit was also bestowed by different countries. However, the guarantee of interest was, oftenly, given in a non careful manner as other benefits conceded by the government. Many of the criticisms related to the grant of benefits in concessions question not the benefits per se, but the way they were bestowed and, afterwards, regulated. If, on one hand, the guarantee of interest has sustained unprofitable railways, it has also had the ability to promote lucrative railways, that have become free of this subsidy and have developed their own national economy. It is the case of the four investigated companies: they have revealed themselves profitable during the 1880s, despite the differences that distinguished them: extension, differences at the colonization of the regions in which they were built, gauge, passenger and good carried, among others.
167

Estudo de vibrações induzidas por linhas férreas / Study of railway-induced vibrations

Silva, Gabriel Gomes 13 March 2017 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-05-17T11:44:43Z No. of bitstreams: 2 Dissertação - Gabriel Gomes Silva - 2017.pdf: 4421932 bytes, checksum: 33a250f4d0b7e79decbef522f34aa0e2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-17T11:49:41Z (GMT) No. of bitstreams: 2 Dissertação - Gabriel Gomes Silva - 2017.pdf: 4421932 bytes, checksum: 33a250f4d0b7e79decbef522f34aa0e2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-17T11:49:41Z (GMT). No. of bitstreams: 2 Dissertação - Gabriel Gomes Silva - 2017.pdf: 4421932 bytes, checksum: 33a250f4d0b7e79decbef522f34aa0e2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-13 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Vibrations in the soil, induced by the passage of trains on railways, can cause countless effects in the areas bordering the railroads. In most problems, resort to simplified models of the system of interaction between rails foundation and trains for predicting responses that meet certain expectations, especially in order to avoid damaging nearby structures and also avoid discomfort of the people residing in areas surrounding the railway lines. Several soil-foundation interaction models have been developed seeking to get the answer to a foundation when subjected to static and dynamic actions, however, this response depends on multiple factors such as the nature and the mechanical characteristics of the terrain, the geometry of the elements involved, the rigidity of the foundation and the nature of his own excitement. Also of great importance in this type of analysis is the use of optimization techniques in order to obtain projects that are more realistic and safe from an engineering point of view. In this paper, was proposed a study of the effect of vibrations on railway lines, where it aims to model a system coupled between foundations and rails, subject to dynamic actions, in order to simulate the displacement in the time domain and in the domain of the frequency, using optimization for the construction of an optimum design that can attenuate the amplitudes of vibration of the system. / Vibrações transmitidas no solo, induzidas pela passagem de trens sobre vias férreas podem causar inúmeros efeitos nas áreas próximas às ferrovias. Na maioria dos problemas, recorre-se a modelos simplificados do sistema de interação entre trens, trilhos e fundação para a previsão de respostas que atendam a certas expectativas, principalmente, de modo a não danificar estruturas próximas e também evitar desconforto das pessoas que residem em áreas circunvizinhas a linhas férreas. Vários modelos de interação solo-fundação já foram desenvolvidos buscando-se obter a resposta de uma fundação quando sujeita a ações estáticas e dinâmicas, porém, essa resposta depende de múltiplos fatores, como a natureza e as características mecânicas do terreno, a geometria dos elementos envolvidos, a rigidez da fundação e, ainda, a natureza da própria excitação. Também é de grande importância neste tipo de análise, a utilização de técnicas de otimização visando obter projetos mais realistas e seguros do ponto de vista de engenharia. Neste trabalho, propõe-se um estudo acerca do efeito de vibrações em linhas férreas, onde se tem por objetivo modelar um sistema acoplado entre fundações e trilhos, sujeitos a ações dinâmicas, de maneira a simular o deslocamento no domínio do tempo e no domínio da frequência, utilizando-se de otimização para a construção de um projeto ótimo que possa atenuar as amplitudes de vibração do sistema.
168

Advanced Simulation Methodologies For Crashworthiness And Occupant Safety Assessment Of An Indian Railways Passenger Coach

Prabhune, Prajakta Vinayak 07 1900 (has links) (PDF)
Accidents involving passenger trains happen regularly in India. The reasons for such accidents could be many; such as weather and flooding, faulty tracks, bridge collapse, collisions caused by signaling errors, mechanical failures, driver error, sabotage etc. The annual accident-related deaths as a percentage of the total number of passengers carried by Indian Railway may seem to be negligible, but the aim should be to achieve zero fatality as every single person killed is an irreplaceable loss to his/her family. It needs to be mentioned that in addition to fatalities for which exact numbers are not available, serious injuries and permanent disabilities caused by train accidents in India at present stand completely unaccounted for. In the absence of a large scale renovation and crash avoidance measures coupled with the propensity to increase the number of trains every year, enhancing passive safety is crucial i.e. crashworthiness and occupant safety of passenger coaches of Indian trains. In the current work, crashworthiness and occupant safety of the existing typical three-tier cabin passenger coach of Indian Railway in an event of collision accident are assessed with the aid of a finite element analysis. In the light of the published work on research in railroad equipment crashworthiness, the current work is intended to envisage the methodology to assess the Indian Railway passenger coach from the point of view of the crashworthiness and occupant safety using CAE (Computer aided engineering) based approach. It is involved with an extensive study of the structural crush behavior of an individual passenger coach car and its effect on the interaction between occupants and the coach interior. Here the structural crush behavior of a typical three-tier cabin passenger coach is evaluated for the head-on impact against a fixed and rigid barrier. The occupant response for the same scenario is also studied which can be viewed as a component of the actual occupant response due to the structural crush behavior of the passenger coach. This can give useful estimates of injury severity and fatalities that may occur in actual accidents. An FE model of the passenger coach structure was built and validated using International Railway Union (UIC) specified code OR 567-design requirements in terms of static loads constituting structural proof cases. These proof cases specify the static load values the coach body structure should withstand without any permanent deformation or failure when applied at the specified locations on the structural ends across the longitudinal axis. In addition, a favorable correlation between the simulation and actual experiment for drop impact behavior of the open section specimens, namely C-section and I-section, was obtained to validate the simulation methodology. LS-DYNA a nonlinear dynamic explicit FE solver was used to carry out all the dynamic impact simulations involved in the current work. The material modeling takes into account the strain rate effect which is essential for the material impact behavior study. The contact modeling was done using penalty contact method. The degrading effect of the buffer on the structural crush patterns which induced the undesirable global bending and jackknifing of the whole coach structure was demonstrated with the help of dynamic impact simulations of the coach structure. The quantification of occupant injury was done by occupant safety simulations using the Hybrid III 50th percentile male dummy FE model. The dummy having been designed for simulating automobile accident scenarios, its contacts had to be adapted to suit the excessive mobility conditions in the coach interior. The dummy was revalidated successfully for the head drop test, pendulum chest impact test, neck flexion and extension test and knee impact test. Impact simulations for three different speeds were performed by positioning the dummy close to the impact point. Injury criteria such as Head Injury Criterion, Chest Deceleration, Knee force level and Neck extension-flexion moments were used to estimate the injury severity level and fatality rate.
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Systém pro detekci vlakových náprav a jejich číslování dle Mezinárodní železniční unie / Detection of Train Axles and Their Numbering According to International Union of Railways

Dvořák, Petr January 2015 (has links)
The diploma thesis deals with design and development of the system which detects and numbers train carriages in compliance with International Union of Railways. Firstly, methods for correct detection of passing wheel including time records are analysed. Also, the summary of detection sensors used in railway industry is referred. I analyse meaning of each digit in numbering according to the UIC. The system solution is designed and the interaction and communication with other sub-systems is discussed. I put emphasis on the kind of solution that returns as accurate record as possible under any circumstances. The system operates in real time. Further, the results of measuring program are back-tested in order to verify low-deviation of measuring system component. The following section describes program prototype, which processes the recorded data. The algorithms which I used for the detection of wheel and train carriages are described. In the following chapter I discuss the usage of an external camera detecting the numbers in accordance to the UIC. In the last chapter, I describe the test environment in which the solution has been tested, and summarize the results of tests on a real life railway.
170

Provisioning Johannesburg, 1886-1906

Cripps, Elizabeth Ann 02 1900 (has links)
The rapidity of Johannesburg’s growth after the discovery of payable gold in 1886 created a provisioning challenge. Lacking water transport it was dependent on animal-drawn transport until the railways arrived from coastal ports. The local near-subsistence agricultural economy was supplemented by imported foodstuffs, readily available following the industrialisation of food production, processing and distribution in the Atlantic world and the transformation of transport and communication systems by steam, steel and electricity. Improvements in food preservation techniques: canning, refrigeration and freezing also contributed. From 1895 natural disasters ˗ droughts, locust attacks, rinderpest, East Coast fever ˗ and the man-made disaster of the South African War, reduced local supplies and by the time the ZAR became a British colony in 1902 almost all food had to be imported. By 1906, though still an import economy, meat and grain supplies had recovered, and commercial agriculture was responding to the market. / History / M.A (History)

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