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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.
331

Vývoj maziva pro temeno kolejnice / Top of rail lubricant development

Skurka, Šimon January 2021 (has links)
Friction modification within the wheel-rail interface is an important way of achieving ecologically friendly transportation of both persons and goods. This thesis aims to develop a new TOR lubricant, which will be able to maintain suitable frictional conditions while securing minimal adhesion required for traction. All measurements were carried out on tribometer MTM in the ball-on-disc configuration. In the first step, individual components were examined. More complex compositions were measured after that and the three best of them were compared with commercial TOR lubricants. The results show a good ability of developed compositions to maintain required adhesion, reduce wear, and all of them had resistivity against over-lubrication. Lastly, the process of lubricant verification before its application in real traffic was discussed.
332

Accessibility of Bay Area Rail Transit Stations: An Evaluation of Opportunities for Transit Oriented Development

Fang, Kevin M 01 September 2009 (has links)
Many groups have been pushing for a shift from automotive oriented transportation and land use, to transit-oriented transportation and land use. These groups have many valid reasons. However, just as it is fair to point out issues about auto travel, so too is it fair to see how transit performs at meeting certain goals. This paper examines the important characteristic of accessibility afforded to travelers. This is quantified through the calculation of accessibility indexes for stations, for the specific case of two existing rail systems and four proposed rail extensions in the San Francisco Bay Area. As a whole, the four extensions investigated increase regionwide rail accessibility by 18.5 percent, not an insignificant increase. However, the new stations are on average less accessible than their existing counterparts. Two of the four extensions perform well on accessibility measures, either their stations have high accessibility, or jobs around them contribute to high accessibility for nearby stations. The other two extensions however perform poorly on accessibility measures. In a time of limited resources, the accessibility results clearly indicate how the four extensions should be prioritized. The more successful extensions have good access to activity centers. Extensions having good connectivity with other lines can also enhance accessibility if providing significant travel time savings.
333

Analýza a návrh uložení pojezdu výtahu v lakovně karoserií / Analysis and design of elevator storage drive in the paint car bodies

Polášek, Lukáš January 2012 (has links)
The aim of this diploma thesis is making a degradation analysis of guide track for car body elevator and creating a new design of storage drive according to acquired knowledge. In the first part of this thesis is written research dealing with the issue of lifting equipment. Afrer this part follows load calculation with consideration of dynamic effects. Based of this calculation are created four different variants of the new travel lift with the use of various types of rollers (metal and plastic) moving through different types of rails (elevator and square profil). For most appropriate selected variant are created two differend designs of the new travel lift. Design variants are described in detail and check by finite element method, giving rise to the final selection of variants. For the selected variant is produced complete drawings.
334

Návrh zakřivení rámu dveřního křídla / Design of Door Frame Curvature

Merkl, Martin January 2015 (has links)
This diploma thesis deals with the design of door frame curvature, meant for rail vehicle. Flat glass is adhesively bonded onto the curved door frame and due to the elastic deformation the door frame bends backwards. Hence the door frame must be bend with reserve so that the elastic deformation is covered. Finite element analysis of currently manufactured door with constant curvatere has been carried out, with this analysis it has been checked that the chosen problem approach is suitable. Design of door frame curvature is then made for door frame with combined curvature (different for lower and upper part of door frame). The aim of this thesis was to design the curvature so that after glass is bonded onto it, the door frame will have the right dimensions.
335

Robotická manipulace s vysokotlakým zásobníkem paliva Common Rail při procesu svařování laserem / Robotic manipulation with Laser Welded Common Rail during the laser welding process

Bužga, Petr January 2015 (has links)
This master’s thesis deals with a description of Laser Welded Common Rail, which is produced by the company Bosch Diesel, s. r. o. in Jihlava. The theoretical part is focused primarily on a proposal for an industrial robot which would be manipulated with Common Rail during the laser welding process. The practical section is concerned with changes in the current paths of the robot to reduce production times, and to avoid using the same parts of the robot for the whole duration it is being manipulated with the Common Rail. At the end of this master's thesis is a techno-economic evaluation of previous alternatives, and it determines the appropriate option for robotic manipulation with the Common Rail during the laser welding process.
336

Design tramvaje / Design of Tram

Řihánek, Šimon January 2015 (has links)
The content of this diploma thesis is design of a low-floor tram, primarily intended for inner-city use. The thesis includes a brief summary of the historical development, analysis of current trends in tram design and analysis of currently used technical solutions. The main part is devoted to the design process, resulting in shape and graphical solution of the exterior and interior arrangement while respecting the structural and ergonomic requirements in respect of passengers and the driver of the vehicle.
337

Design elektrické lokomotivy / Design of Electric Locomotive

Chropovský, Jiří January 2016 (has links)
The topic of this master’s thesis is design of electric locomotive, more specifically universal independent machine made for pull of personal trains and industrial trains as well. The main aim of this design is to create compact design which follows current estetical trends and fulfill technical and ergonomic needs.
338

Hamba-kahle : an interior intervention to long-distance rail travel in South Africa

Jacobs, Anneli January 2014 (has links)
Public rail transport interiors must be adaptable and cater to a wide target market to address the diverse needs of the South African public. Local rail transport competes directly with air travel for market share. Currently, local rail transport fails on both accounts. The failure to invest in and update rail infrastructure has resulted in a desperate need to play catch up with decades of international railway evolution – a need especially visible in the interiors of local long-haul trains. The design and aesthetic identity of transport interiors are generic, dated and fail to address the functional and aesthetic needs of contemporary South African travellers. As a result, these interiors fail to establish an identity synonymous with our unique demographic makeup. The current state of local long-haul passenger rail interiors was investigated through the use of a heuristic inquiry. An Electro Star Multiple Unit train structure was then selected in which an interior insertion is made. Hamba-Kahle addresses the physical and psychological discomfort in the train interior, the absence of social spaces, the disregard for wayfinding and the lack of contextual identity. The design challenges the insular train interior layout and divides the interior into different spatial zones. A Budget Sitter car, Premium Sitter car, Budget Sleeper and Universal Car provides seating variation for passengers and in turn integrates a wide target market. Break-away spaces are also incorporated. The programme and the spaces it creates assist the interior in mediating between private and public spaces. It facilitates chance encounters and supports retractable privacy. The interior reinforces adaptability in the use of spaces while adhering to universal design principles. The scenery from the surrounding landscapes is used in the design to enrich the interior spaces and improve the embodied experience of the user. In establishing a contemporary South African identity, a sense of place is created with which passengers can identify and feel physically, psychologically and socially comfortable in. / Dissertation (MInt(Prof))--University of Pretoria, 2014. / Architecture / MInt(Prof) / Unrestricted
339

Geotechnical investigations for the Gautrain Mass Transit Rapid Rail Link over dolomite bedrock in the Centurion area, South Africa

Momubaghan, Glory Adeoye 22 May 2013 (has links)
The Gautrain Rapid Rail Link is a state-of-the-art rail route and one of the ten Spatial Development Initiatives planned in Gauteng Province, South Africa. The route comprises two links, namely a link between Tshwane (Pretoria) and Johannesburg and a link between OR Tambo International Airport and Sandton. A total of 10 stations are linked by approximately 80 kilometres of rail along the proposed route. Between Johannesburg and Pretoria in the southern Tshwane region, the rail alignment is underlain by dolomite bedrock for approximately 15km in the vicinity of Centurion between Nelmapius Drive and The Fountains, including nearly 6km elevated on a viaduct. The stability of the rapid rail link constructed over the dolomitic sections was considered a major project risk due to its proneness to sinkholes and subsidences along this route. Construction on heterogeneous soils, pinnacled bedrock and other geohazards posed major challenges to the construction team. To facilitate detailed design and adapt proper foundation options for the viaducts founded over the dolomitic terrain, rigorous and comprehensive ground investigations were conducted by the Bombela Civils Joint Venture (BCJV). This work presents the different ground investigation methods used and how the results have led to the adoption of five suitable foundation solutions namely: large diameter shafts to rock, piles to rock, floating foundations over grouted ground, spread footings on shallow bedrock and concrete U shaped structures. Additional information available on a CD stored at the Merensky Library on 3rd Floor / Dissertation (MSc)--University of Pretoria, 2012. / Geology / unrestricted
340

Oh, the Places You'll Move: Urban Mass Transit's Effects on Nearby Housing Markets

Yue Ke (9192656) 31 July 2020 (has links)
The last couple of decades have seen a renewed interest among urban transportation planners in light rail transit (LRT) systems in large cities across the United States (US) as a possible means of addressing negative transportation externalities such as congestion and greenhouse gas emissions while encouraging the use of public transit [1]. LRT infrastructure investments have also gained traction as a means of revitalizing decayed urban centres because transportation infrastructure developments are highly correlated with economic growth in surrounding areas [2]. <div>The primary objective of this dissertation is to examine the externalities associated with LRTs during its the construction and operations phases. In particular, three areas of concern are addressed: (1) The effect that proximity to LRT stations </div><div>have on nearby single family residences (SFRs) throughout the LRT life-cycle; (2) the effect that directional heterogeneity between LRT stations, the central business district (CBD), and the SFR; and (3) the longer term effects on nearby populations due to LRT operations. To answer the first two research objectives, quasi-experimental spatial econometric models are used; to address the last objective, a-spatial fixed effects panel models are developed. The analyses primarily relies on SFR sales data from 2001-2019, publicly available geographical information systems data, as well as demographic data from eight 5-year American Communities Surveys (ACS). Charlotte, NC, a medium-sized US city, is chosen as the site of analysis, both due to the relative novelty factor of its LRT in the region and data availability.</div><div>The results show that SFR values are positively associated with proximity to LRT stations in the announcement and construction phases but negatively associated with proximity to stations once the LRT is operational. Additionally, potential homeowners with prior experience with LRT do not behave any differently than potential homeowners with no prior experience with LRT in terms of willingness to pay to live a certain distance from LRT stations. Further, directional heterogeneity is shown to be a statistically significant source factor in deciding the extent to which house-buyers are willing to pay to be near LRT stations. Lastly, distance from LRT stations are found to have no statistically significant effect on changes in the racial composition of nearby areas but have significant positive effects on educational attainment and average median incomes of residents living in nearby areas over time. </div><div>The contributions of this research are twofold. First, in addition to highlighting the need to use spatial econometric methods when analyzing the effect that LRTs have on surrounding real estate markets, this research provides a framework by which directional heterogeneity can be incorporated into these analyses. Second, this research adds to the existing pool of knowledge on land use externalities of LRT through incorporating the life-cycle of LRT from announcement to operations. Furthermore, this research examines the effects that LRT have on surrounding populations in transit adjacent areas to provide a look at the broader effects of LRT over time. </div><div>A major challenge in the analyses conducted in this dissertation is its reliance on SFR sales data. Urban areas near LRT may contain additional land uses. In order to fully determine LRT’s effects on its surrounding area, one should examine the proximity effects on all land use types. Furthermore, LRT stations and rail lines are assumed exogenous, which may not be the case as public hearings and town halls during the planning phase may influence stations’ locations. Future research should seek to understand how the circumstances surrounding the planning process could indirectly affect the socio-demographic characteristics in transit adjacent areas over time. Finally, additional research is needed to better understand the extent to which LRT affects urban intra- and inter-migration. Knowing the population repulsion and attraction of LRT can help planners design facilities to better serve the public.</div>

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