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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.
241

Evaluating mega urban transport project: planning implications of West Rail

鄭沛勤, Cheng, Pui-kan. January 2008 (has links)
published_or_final_version / Urban Planning and Environmental Management / Master / Master of Science in Urban Planning
242

A station-level analysis of rail transit ridership in Austin

Yang, Qiqian 30 September 2014 (has links)
Community and Regional Planning / In the past two decades, Austin has tremendous population growth, job opportunity in the downtown core and transportation challenges associated with that. Public transit, and particularly rail, often is regarded as a strategy to help reduce urban traffic congestion. The Urban Rail, which combines features of streetcars and light rail, is introduced into Austin as a new transit rail. The City of Austin, Capital Metro and Lone Star Rail are actively studying routing, financial, environmental and community elements associated with a first phase of Urban Rail. This thesis collected 2010 Origin and Destination Rail Transit Survey data from Capital Metropolitan Transportation Authority. The research focuses on the rail transit ridership. Two regression models are applied to analyze the factors influencing Austin rail transit ridership. One model is focusing on the socioeconomic characteristics. One model is focusing on the spatial factors. Our model shows that demographic factors have more significant effect than spatial factors. In addition, this work also tries to analyze the correlations between those factors and make recommendations based on the analysis result. / text
243

On the Influence of Rail Vehicle Parameters on the Derailment Process and its Consequences

Brabie, Dan January 2005 (has links)
No description available.
244

R65 tipo bėgio termitinio suvirinimo mechaninių savybių tyrimas / The investigation of machanical properties of welding quality of R65 type

Rauduvė, Mindaugas 15 June 2010 (has links)
Baigiamajame magistro darbe nagrinėjama termitiniu būdu skirtingais parametrais suvirintų bėgių jungčių kokybė. Analizuojama termitinio suvirinimo mišinio kiekio bei pakaitinimo laiko įtaka suvirintų jungčių kokybei. Tam, kad būtų nustatytos suvirintų jungčių mechaninės savybės, buvo atlikti šie bandymai: viršutinės bėgio dalies kiečio bandymas, lėtojo lenkimo bandymas, termiškai suminkštintos zonos kiečio pasiskirstymo matavimas, ilgalaikiai bandymai. Tyrimais nustatyta kokią įtaką, turi suvirinus bėgių jungtis be pakaitinimo, esant skirtingiems pakaitinimo laikams ir skirtingam termito kiekiui. Remiantis gautais rezultatais pateiktos išvados. / In the final masters degree thesis examines the quality of using different parameters Aluminothermicaly welded rail joints. Influence of the quantity of Aluminothermic welding mixture for quality of welded joints, and heating time is analyzing. In order to determine the mechanical properties of welded joints following tests had been made: hardness test of upper part of the rail, long term bending test, hardness test of the distribution of heat-softened area, other long-term tests. Results of research have determined the influence of different heating time and different quanity of thermites content for welded joints without using heating. Based on this results the final conclusion was presented .
245

Thermal comfort on train journeys

Kelly, Lisa K. January 2011 (has links)
This thesis presents a body of work conducted to determine thermal comfort on train journeys. Relatively little research has been conducted on trains in comparison with the vast body of work conducted within building environments. This thesis aimed to expand our knowledge of rail passenger thermal comfort throughout the journey; platform to destination. The train journey was separated into its component parts and analysed by conducting both laboratory and field experiments that either simulated or measured aspects of a train journey. Laboratory experiment 1 examined appropriate methods of data collection during train journeys. Participants (9 males and 9 females) were exposed to a simulated train environment three times and used a different data collection method on each occasion; a paper-based method, a voice recorder or a Personal Digital Assistant (PDA). Results concluded that the three methods can be used interchangeably when recording thermal comfort data. Participants preferred the PDA over the other two methods because they felt it afforded them a level of privacy in addition to blending in with other rail passengers using similar technologies. The second laboratory experiment measured thermal comfort following a change of environment. Participants (12 males and 12 females) were exposed to three environmental conditions (warm, neutral and slightly cool) in a thermal chamber on three separate occasions. The exposure lasted 30 minutes, after which, participants entered a new environment that was the same on each occasion (slightly cool). Results showed that overshoots in sensation (beyond those predicted by the Predicted Mean Vote thermal comfort index PMV) are observed following downward steps (warmer to cooler) in environmental conditions. No overshoots were observed following the upward step (cooler to warmer) in environment, with sensations immediately reflecting the predicted steady-state values. Laboratory experiment 3 (22 males and 26 females) expanded the research conducted in laboratory experiment 2 by exposing participants to greater magnitudes of environmental change. In addition, sensation was measured after this change until steady-state was reached. Participants were exposed to four environmental conditions (cool to warm to neutral to cool or cool to cold to warm to cool) consecutively over a 2 hour period with 30 minutes spent in each location. Results demonstrated similar effects to those observed during laboratory experiment 2 with overshoots observed following downward steps in environmental conditions and none observed in the opposite direction. Sensations demonstrating overshoots gradually increased until steady-state was achieved after approximately 25 minutes. Field experiment 1 (12 males and 32 females) measured thermal comfort while boarding trains. Participants were taken on a short train journey and recorded sensations whilst on the platform and during boarding. Results showed that overshoots may also be observed following step up and step down in environments. It is hypothesised that change in air velocity is influential in this effect. Thermal comfort throughout a train journey was measured in field experiment 2. Participants (16 males and 16 females) reported on thermal comfort on the platform, during boarding and throughout a return train journey from Loughborough to London St Pancras. Results also demonstrated overshoots following upward transients indicating that there are factors in the field that do not occur in laboratory conditions. Subjective parameters reach steady-state after approximately 20 minutes and PMV accurately predicted sensations during the journey. Again, air velocities may have interacted with other variables resulting in the overshoots following upward steps in environmental conditions. Laboratory experiments 2 and 3 resulted in the creation of a model predicting sensation following a change of environment, PMVTRANS. When the model was compared with the field data, it could not accurately predict sensations observed during transients. It also could not predict the sensation overshoots observed following upward transients. A new model is now proposed, NEW PMVTRANS. This model shows greater correlation with actual sensation than PMV; however it does require further validation from field data. Research has shown that PMV is an accurate estimator of sensation within a train carriage and should be used by train designers to optimise the environmental conditions for passengers.
246

The wear of bainitic and pearlitic steels

Garnham, John Ernest January 1995 (has links)
The rolling-sliding dry-wear behaviour of a series of bainitic steels and a standard pearlitic rail steel have been compared over a range of contact stress and creepage conditions applicable to the British Rail network. A rolling-sliding wear machine has been constructed - LEROS - which allows very high contact stresses to be combined with high creepages under well controlled conditions. Materials were tested on LEROS and on an Amsler machine. Limited vibration analyses were carried out on both machines and compared with the frequencies of disc surface periodic undulations. No direct linkage was determined. Despite better standard mechanical properties, the wear resistance of lower carbon bainitic steels was inferior to that of the pearlitic steel. A bainitic steel with the same carbon content as the pearlitic steel wore a little less, but at considerable expense to the pearlitic wheel steel counter-material in the wear couple. The wear resistance of bainitic steels depends upon the volume fraction of hard phase, such as carbide and martensite-austenite phase, for rolling-sliding as well as other types of dry wear loading. Pearlitic steel performs exceptionally well under certain rolling-sliding conditions, such as the majority seen in these tests, since the lamellar microstructure is modified so as to present a greater area fraction of carbide hard phase at the wear surface, a fraction in excess of bulk volume fraction. Recommendations are made for the dry wear applicability of the steels.
247

Analýza difenciace cenové, časové a vzdálenostní akcesibility v rámci sítě ČD / Analysis of price, time and distance accessibility diferentitation in the Czech railroad system

Hanes, Zuzana January 2010 (has links)
Analysis of differences in price, time and distinct measures of accessibility for eské dráhy Abstract The main aim of this thesis is to resolve the issue of accessibility in the passenger rail network of eské dráhy in the Czech Republic. Secondary objectives are the analysis of distance, time availability, and price of passenger rail service. The main sources are the Railway Timetable 2009 and the geographic database Arc R 500. Basic tool for the processing is geographic information system (GIS) with extension Network Analyst. The main aim of the thesis is to provide a database with the values of distance, time availability and price. Secondary aims are to produce partial maps which present various types of accessibility. Part of the results are also the methodology for establishing different kinds of accessibility, the evaluation of methods used, and quality assessment models used in relation to the database and partial results of comparison with the literature. Keywords: transport accessibility, rail transport, network analysis, accessibility, availability of models, Network Analyst
248

Souvislosti rozmístění socioekonomických charakteristik obyvatelstva a hospodářství ve vztahu k železniční síti v Československu v letech 1921 a 1930 / Connection between distribution of socio-economic characteristics of population and economy in relation to railway network in Czechoslovakia in 1921 and 1930

Marek, Martin Václav January 2015 (has links)
Connection between distribution of socio-economic characteristics of population and economy in relation to railway network in Czechoslovakia in 1921 and 1930 Abstract Transport is closely related with social and economic processes in space and they affect each other. History of transport, and economy and history of the population are themes quite well covered. Attempts to synthetically cover history of transport and society and its activities in the space have not been numerous, if any they only referred to certain examples, although the transport, especially rail, is mentioned as an important factor of development. The diploma thesis analyzes statistical dependece of selected demographic and socioeconomic characteristics of national censuses in 1921 and 1930 and economic characteristics and agriculural units in 1930 on rail infrastructure in the Czechoslovak Republic. The key statistical data are selected census results (eg. age of population, literacy and inhabitans in the sector of the national economy), results of census of economic and agricultural units (for example units equipment) at the level of administrative units in Czechoslovakia. Spatial data (maps) are an important source, too. These allow statistical and visualization operations in the GIS. They had to be digitized in order to create map...
249

Barrel wear reduction in rail guns: the effects of known and controlled rail spacing on low voltage electrical contact and the hard chrome plating of copper-tungsten rail and pure copper rails

McNeal, Cedric J. 06 1900 (has links)
Approved for public release, distribution is unlimited / 100 m/s). Low voltage electrical contact was not maintained for some experimental shots and non-parallel rails were the suspected cause. In this thesis, we used a non-contact capacitive sensor to determine rail spacing to within 2/kAcm10mael, so that the rails will be parallel within small tolerances. Several rails were used in these experiments: 75-25 copper-tungsten, chromium-plated 75-25 Cu-W, and chromium-plated pure copper rails. Improving the control of rail spacing and parallelity did not ensure low-voltage electrical contact for our configurations. The largest damage was observed for chromium-plated copper rails and the least damage occurred for chromium-plated 75-25 Cu-W rails. / Lieutenant, United States Navy
250

Service advancement strategy in analyzing the future of LTE-R for next-generation smart trains

Ligwa, Mario January 2018 (has links)
Thesis (Master of Engineering in Electrical Engineering)--Cape Peninsula University of Technology, 2018. / This research investigates and presents selected issues and aspects related to the railway mobile network (GSM-R) analysis and its shortcomings. Research studies show that millions of South Africans commuters are dependent on trains for daily movement activities, which significate contribute towards economic growth. Over the two decades, the exponential growth in wireless broadband service indicates the need for GSM-R improvement so that it can support the modern IP based protocol. The principle of implementing the digital network in railway already demonstrated significate improvement in the railway environment, especially in communication and signalling. Train traffic and train communications are the most critical aspects of railway scenarios due to safety and reliability. Both features form fundamental content to this research thesis. The exponential increase in Internet protocol (IP) based services and higher bandwidth requirements in modern technology applications have pushed the current Global system mobile for railway (GSM-R) technology to its maximum capacity as such the (GSM-R) platform is going to obsolete soon. There is a great need for the development of improved IP based networks for the future of the next generation network for fast smart trains to meet desired higher data low latency while improving quality of service (QoS). The focus of the research study is on modelling of an effective sharing method between public LTE and LTE-R without addition mobile infrastructure by utilizing train access unit (TAU), the main purpose is for public network (LTE) to handle railway emergency service including drop calls to improve quality of service (QoS). The second focus is an improvement of signal reception by spreading signals over wide spectrum range by utilizing Orthogonal variable spreading factor (OVSF) technique where LTE-R is not deployed as noted that this technique is deployed in the 3G network. The proposed scheme has adopted features in modern evolution communication and both scenarios were investigated modelled and simulated with comparison results showing better improvement in proposed conditions, there are many challenges in high-speed railway such as handover procedure and Doppler shift due to the velocity of the moving train.LTE-R has provided many solutions such as seamless handover, capacity availability as well as enhanced performance in both uplink and downlink. Digital evolution for railway GSM-R has been deployed in most developed countries in Europe and also expanded into Africa, there is a greater need for the seamless network to be developed due to an increased number of packet based services. Urban rail is the backbone of public transport in South Africa which is the Passenger Rail Agency of South Africa (PRASA). PRASA, and is the parent operator. Currently, PRASA has implemented digital railway network (GSM-R) to meet a high standard in railway. Modem demand and challenges require a cost-effective system to support IP orientated systems due to an increased number of packet-based services in the railway sectors.

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