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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.
31

Técnica, modernização e produção do espaço: um estudo sobre o papel da estrada de ferro nas transformações sócio-espaciais da zona alta sorocabana / Technique, modernization and production of space: a study on the role of the railroad in the socio-spatial transformations of the Sorocabana High Zone

Paulo Passini Marques 17 December 2009 (has links)
Com a chegada da estrada de ferro no Estado de São Paulo na segunda metade do século XIX, começam a se romper as barreiras espaciais que encarceravam a produção cafeeira e impediam a economia de avançar por outras áreas do estado. No começo do século XX a ferrovia se transforma em ponta de lança do avanço das frentes pioneiras rumo às áreas desconhecidas do sertão paulista. Através da sincronia do avanço ferroviário, do crescimento demográfico e da inserção de uma economia de mercado, novas regiões vão surgindo na forma de faixas territoriais, que desarticuladas entre si, aglutinam sua economia em torno de seu eixo ferroviário. Com a crise da economia agro-exportadora, e o avanço da industrialização, o caminhão assumiu o papel de elemento de integração regional, função que a ferrovia se mostrou incapaz de cumprir. Começa aí um longo processo de desestruturação do setor, que vai resultar, no final da década de 1980, no intenso estado de abandono e sucateamento da malha ferroviária paulista. Com os governos neoliberais e de estado mínimo de Fernando Collor e Fernando Henrique, as ferrovias passam a integrar o Programa Nacional de Desestatização, sob o argumento de que só a iniciativa privada poderia trazer investimentos e recuperar a malha ferroviária nacional. Passados quase quinze anos das concessões ferroviárias, o que se observa é que, apesar de alguns avanços (impulsionados pelo dinheiro público), a tão sonhada mudança na matriz de transportes está longe de acontecer. Ao mesmo tempo, devido às desativações de trechos considerados antieconômicos pelas concessionárias, economias regionais são inviabilizadas, refletindose em grandes prejuízos sociais. Este trabalho tem como objetivo trazer a questão da importância da ferrovia para as economias regionais, utilizando como estudo de caso a Região da Alta Sorocabana, no oeste paulista. A presente dissertação procura também analisar o papel da ferrovia nas transformações sócio-econômicas da região, e sua atual importância na economia regional, fato que tem levado grande parte da sociedade e de diversos setores da região, ao discurso unânime de que uma possível retomada do crescimento regional passa necessariamente pela revitalização da malha ferroviária e sua integração a outros modais de transportes. / With the arrival of the railroad in the state of São Paulo in the second half of the nineteenth century, begins to break down the spatial barriers that incarcerated the coffee production and prevented the economy to move forward in other areas of the state. In the early twentieth century the railroad becomes the spearhead of the advance of pioneer towards the unknown areas of the interior of São Paulo. By timing advance rail, population growth and the inclusion of a market economy, new regions are emerging in the form of regional bands that were broken up between themselves, they come closer together their economy around their axis rail. With the crisis of the agro-export economy and the advance of industrialization, the truck starts to play the role of element of regional integration , function that the railroad was unable to meet. It starts there a long process of disintegration of the sector, which will result, in the end of 1980s, in the intense state of abandonment and scrapping of the paulista railway . With the neoliberal governments and Fernando Collor and Fernando Cardoso s minimum state, the railroads have moved into the National Program of Privatization, arguing that only the private sector could bring investments and recover the national rail. After nearly fifteen years of railway concessions, which is observed is that , despite of some progress (driven by public money), the long awaited change in the matrix of transport is far from happening. At the same time, due to the deactivation of passages considered \"uneconomical\" by utilities, regional economies are made impossible, reflecting in large social losses. This work will analyze the importance of the railroad in socio-spatial transformations of the various regions of São Paulo under its influence, using as a case study of Upper Sorocabana region. It also seeks to show the current situation of the rail passage in question, leading to a reflection about the unanimous discourse of society and different sectors of the region, that a possible resumption of regional growth , requires necessarily the revitalization of the railroads and their integration to other modes of transport.
32

Comparação do desempenho de materiais de sapatas ferroviárias em ensaios dinamométricos e maquinas krauss / Comparison of performance of materials for railroad brake shoes using full-scale dinamometer and krauss machine

Santos, Valdecir José dos 23 August 2018 (has links)
Orientador: Auteliano Antunes dos Santos Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-23T01:53:22Z (GMT). No. of bitstreams: 1 Santos_ValdecirJosedos_M.pdf: 11167855 bytes, checksum: 4602f2d43f51266597072a259e482e7f (MD5) Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
33

Estimace determinant poptávky po příměstské vlakové dopravě v České republice / Estimation of Suburban Railway Demand in the Czech Republic

Mlčkovský, Petr January 2011 (has links)
This thesis analyzes railway demand and its determinants in the context of regional railway passenger transport in the Czech Republic and Prague suburban railway system. Special attention is devoted to examining the impact of new trains on the demand for the selected route of Jizerskohorské Railway. In particular models, I utilize as estimation procedure and difference-in-differences estimator. Panel data analysis found, in line with other published studies, short-run inelastic nature of demand. In order to increase revenue to railway operator, one must distinguish between a group of dependent and discretionary riders whose elasticity is different. Effect of buying new trains can be substantial, especially on less frequented routes with a greater proportion of private car holders.
34

RELIABILITY ANALYSIS OF REPAIRABLE SYSTEMS WITH COVARIATES: A CASE STUDY OF RAILWAY TRACK

Rincon Franco, Alvaro Andres January 2021 (has links)
Linear assets are complex industrial systems that extend from one geographical region to another. Given the criticality of the industrial activities linked to them, it is vital to accurately estimate the systems' reliability. However, this task can be complex as the operational, maintenance and design conditions vary largely along linear asset thereby causing heterogeneity thus complicating the reliability analysis. This leads to inadequacy of the traditional single-parameter reliability approach that uses time as the only predictor variable. This thesis job reviews the existing methods to include explanatory factors into the analysis as covariates. Then, a workflow process is proposed to describe the sequence of steps and decisions needed to carry out the appropriate analysis. The presented flowcharts show how to deal with challenges that are often present in the industrial field. Approaches for dealing with multicollinearity, categorical and continuous covariates, time-dependent covariates, and repairable systems are treated in this work. Subsequently, a case study of railway track is presented as a repairable system with several covariates and failure times as provided by the Swedish Transport Administration. Two different models based on proportional hazard models i.e. the AG (Andersen-Gill) and the PWP(Prentice–Williams–Peterson) methods were run to estimate the regression parameters. Some other functions associated with reliability are obtained from the models such as the cumulative hazard rate and the probability of non-occurrence of the next recurrent event.  In addition, to check the goodness of fit from the obtained models, the Cox-Snell residuals are estimated and used to verify if the estimated parameters fit the data. This procedure is done using a graphical method. From the goodness of fit test, it can be concluded that the PWP model performs better than the AG model. However, the fit is not good enough thus other model validation residual-based techniques are suggested as future work to investigate the reason for the discrepancy. Finally, some actions to deal with multicollinearity are recommended, including using a frailty model and the possibility of reformulating the covariates.
35

Without motion there cannot be any life : the rise & fall of the 1889 Railway Commissioners : railway management & colonial politics in nineteenth century New Zealand

Smith, Bruce H, n/a January 2007 (has links)
In the nineteenth century, the steam railway became, for many people, the superior conduit for the inland translocation of people and freight. Once devised, steam railways offered such a huge improvement on previous modes and made such a dramatic change to the unity, organisation and commerce of most countries that almost everyone wanted one. New Zealand proved no different, but was faced with not only the twin problems of low population and often rugged geography, but also serious economic problems from difficult world trading conditions and a debt greatly increased by railway construction costs. In the later 1880s, a conservative government decided to vest the Government Railways in independent Commissioners to try to improve productivity and cut out political influence, corruption and jobbery in the huge commercial presence the colony�s railways represented. While this move was successful, a change to one-man-one-vote, together with the pivotal 1890 Maritime Strike, saw the country move left in the elections of 1890, bringing to power a Liberal Government. This new Ministry then set out to reduce the autonomy of the Railway Commissioners, taking four years to return the management of Railways to the direct control of the Government. While interesting in itself, this is part of the story of the process of the democratic development of New Zealand. This was a community struggling with the often conflicting demands of using railways to not only service the railway debt but also fulfil public transit requirements, including encouraging settlement and economic growth. The organisation�s monopolistic nature and great economic presence, however, offered multiple, including corrupt, opportunities to support the political aspirations of those in power, while offering a less than wonderful service to its customers. Taking place against a backdrop of agitation for railway reform, particularly orchestrated by railway activist Samuel Vaile, the outcome can be seen to have been less than completely desirable for the economic development of the country or its people. This was despite huge support for the principal activist against the Railway Commissioners, Liberal Premier Richard Seddon.
36

Without motion there cannot be any life : the rise & fall of the 1889 Railway Commissioners : railway management & colonial politics in nineteenth century New Zealand

Smith, Bruce H, n/a January 2007 (has links)
In the nineteenth century, the steam railway became, for many people, the superior conduit for the inland translocation of people and freight. Once devised, steam railways offered such a huge improvement on previous modes and made such a dramatic change to the unity, organisation and commerce of most countries that almost everyone wanted one. New Zealand proved no different, but was faced with not only the twin problems of low population and often rugged geography, but also serious economic problems from difficult world trading conditions and a debt greatly increased by railway construction costs. In the later 1880s, a conservative government decided to vest the Government Railways in independent Commissioners to try to improve productivity and cut out political influence, corruption and jobbery in the huge commercial presence the colony�s railways represented. While this move was successful, a change to one-man-one-vote, together with the pivotal 1890 Maritime Strike, saw the country move left in the elections of 1890, bringing to power a Liberal Government. This new Ministry then set out to reduce the autonomy of the Railway Commissioners, taking four years to return the management of Railways to the direct control of the Government. While interesting in itself, this is part of the story of the process of the democratic development of New Zealand. This was a community struggling with the often conflicting demands of using railways to not only service the railway debt but also fulfil public transit requirements, including encouraging settlement and economic growth. The organisation�s monopolistic nature and great economic presence, however, offered multiple, including corrupt, opportunities to support the political aspirations of those in power, while offering a less than wonderful service to its customers. Taking place against a backdrop of agitation for railway reform, particularly orchestrated by railway activist Samuel Vaile, the outcome can be seen to have been less than completely desirable for the economic development of the country or its people. This was despite huge support for the principal activist against the Railway Commissioners, Liberal Premier Richard Seddon.
37

An investigation of employee motivation at Botswana railways / John Latolang

Latolang, John January 2011 (has links)
Botswana Railways has been facing low employee motivation and productivity for some time. Companies such as Air Botswana which had been experiencing similar issues decided to privatise to increase its efficiency and, as a result, turned things around. Hence, using both quantitative and qualitative investigation at the Headquarters of the Botswana Railways, this study sought to determine the extent of employee motivation and how to enhance it in order to increase employee productivity. The study revealed that employees' main grievances included poor remuneration and lack of opportunities for growth and promotion. It is recommended that Botswana Railways implements policies and strategies which could uplift employees' morale to increase employee productivity and company output. / Thesis (MBA) North-West University, Mafikeng Campus, 2011
38

Přeprava osob po železnici v českém a německém právním řádu / Rail transport of people in the Czech and German legal system

Ambrož, Jiří January 2015 (has links)
The aim of this thesis is to describe and evaluate the legal system of the public transport of passengers on railways in legal systems of the Czech Republic and Germany, including the influence of European and international law. A comparison of the both of the legislations will be made, alternatively some of de lege ferenda proposals for the Czech legislator will be draft. This thesis deals with the both of domestic and international transport. The thesis is divided into six chapters including the introduction as a chapter one and conclusion as a chapter six. In the second chapter some of the legal terms form the field of transport theory such as transport or carriage are defined. The third chapter describes the historical development of the legal regulations of transport starting at the times of the Roman Empire. The fourth chapter deals with the today`s legislation of the transport. It`s subheads describe the influence of the public law, the sources of transport law, the legal systems of transportation, the contract of carriage and the rights of the parties to the contract. Each subhead describes the Czech legal system following by the description of the German one. When it`s suitable, the comparison of both of the legislations is made. The fifth chapter deals with the international law...
39

Principy vyrovnávání výkonů hnacích vozidel zahraničních železničních dopravců / Principles of Equalizing the Tractions-Engines Power Output of Foreign Provider of Railway Services

Maňák, Ondřej January 2010 (has links)
This diploma thesis "Principles of Equalizing the Tractions-engines Power Output of Foreign Provider of Railway Services" aims to delineate how inequalities in power output emerge and how they are later equalized by provider of railway services. This is one of the crucial topics for operating and putting together international trains. The theoretical basis is then used in the applied part of this thesis to describe and evaluate tractions-engines power output of selected foreign provider of railway services on Czech railway network. For better description there is also a balance of tractions-engines of power output enclose at the end of this thesis to illustrate the position of Czech Railways abroad. The analysis made in the applied part put stress on differentiating the long distance transport from cross-border international transport of passengers. Furthermore, this thesis deals with the implementation of the European Rail Traffic Management System (ERTMS) in the connection with compatibility of the Czech railway network to neighbouring rail networks with emphasis on train safety appliances and the project European Train Control System (ETCS).
40

Mecanismos de desgaste de rodas ferroviárias. / Railroad wheels wear mechanisms.

Alves, Luiz Henrique Dias 26 September 2000 (has links)
Descreve-se os principais tipos de desgaste atuantes em rodas ferroviárias tais como desgaste abrasivo e desgaste por deslizamento. No desgaste por deslizamento os principais mecanismos são deformação plástica, fadiga de contato, fadiga termomecânica, oxidação e escorregamento. Avalia-se o efeito de variáveis como dureza, microestrutura, composição química da liga e escorregamento no desgaste e em seus mecanismos. Compara-se os tipos e mecanismos de desgaste verificados em rodas ferroviárias utilizadas em trens para transporte de minérios, com os obtidos em laboratório através de ensaio de desgaste disco-contra-disco de materiais de roda e trilho. No ensaio, o desgaste foi medido por pesagem dos corpos-de-prova verificando após distâncias predeterminadas a perda de massa. Avaliou-se a influência da carga, dureza, composição química e escorregamento no desgaste. Verificou-se que o desgaste aumenta com a carga e diminui com o aumento da dureza. Aços de rodas com adição de Cromo e Vanádio apresentam um melhor desempenho em desgaste se comparados com aços AAR M 107/208 Classe B ou C. Análise microscópica dos corpos-de-prova após ensaio, mostrou que tal como nas rodas em serviço, os tipos de desgaste atuantes foram desgaste abrasivo e por deslizamento com mecanismos diversos como deformação plástica, delaminação e oxidação. Mecanismo semelhante a delaminação é a formação de escamas ou shelling em rodas. Verificou-se também a formação de camada branca na superfície desgastada, característico de transformação martensítica em aço. Mecanismo similar a este é o de formação de \"spalling\" em rodas. Apresenta-se uma metodologia para desenvolvimento de materiais de rodas, compreendendo ensaios de desgaste em laboratório, produção de rodas e acompanhamento de desempenho em campo, onde se confirma o melhor desempenho de materiais AAR M 107/208 classe C com adição de Cromo e Vanádio se comparado com aços convencionais conforme ) conforme normas AAR M 107/208. / The main types of railroad wheels wear, such as abrasive wear and sliding wear are describe. The main mechanisms of sliding wear are the plastic deformation, the contact fatigue, termomechanical fatigue, oxidation and ship wear. The variables such as hardness, microstructure, chemical composition of alloy and effects of the sliding on wear mechanisms are evaluated. The wear types and mechanisms detected on wheels and rail materials from the real railroad cars tracks, from mining company, are compared with those observed at laboratory testing on disc-against-disc wear testing. The wear rate was measured by mass loss after predefined testing distances. The influence of the load, the hardness and the sliding on the wear rate were also evaluated. It was observed that the wear of the Wheel materials increases with the load increasing and decreases with the material hardness increasing. A better performance was observed for steels AAR M 107/208 class C with Chromium and Vanadium additions when compared to AAR M 107/2088 grade B or C steels. The microscopic examination of the test specimens, as well as on the wheels removed from service, showed occurrence of the abrasive wear and sliding wear with various mechanisms such as plastic deformation, delamination and oxidation wear. A similar mechanism to the delamination is the shelling on wheels. It was observed the formation of White layer on worn surface typical to the martensitic transformation of steel. A similar mechanism is the spalling of wheels material, It is also proposed a methodology for Wheel materials development, including laboratory wear tests, the manufacturing of wheels and the use and attendance of the wheels in service. AAR M 208 grade C steels with Chromium and Vanadium additions presented a better performance when compared the standard AAR M 107/208 steels.

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