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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.
61

Southern Taiwan industries study at Taiwan High Speed Rail Era

Wu, Chih-Shih 20 January 2009 (has links)
Just like Eurotunnel link England & France, by the time Taiwan high speed rail arrive at Kaohsiung and Taipei , the passengers and people at platform welcoming the train, both feel exciting of this tremendous improvement of Taiwan. Taiwan have two highways and a railway for connecting Kaohsiung and Taipei despite many roads that have constructed long before. Even there also has plane to catch if you need time. Therefore, Taiwan high speed rail is a high-tech spine for new era of Taiwan. The distance between Taipei and Kaohsiung is merely 300 kilometer . Unfortunately Southern Taiwan and Kaohsiung didn¡¦t get sources from government fairly the old days. Now through this high ¡Vtech spine Kaohsiung and southern Taiwan can step forward proudly embracing future. Southern Taiwan had Kaohsiung Export Processing Zone and many industrial zones by local government , are not enough for use. Recently Southern Taiwan Science Park and Kaohsiung Software Park and Pingtung Agricultural Biotechnology Park all are built to meet future need. Enterprise can run business in these parks at lower cost than Northern Taiwan. Also , there are many solutions offer by government to help company and enterprise to improve and move in southern Taiwan. This study interview southern Taiwan companies and enterprises. From their point of view to see Taiwan high Speed Rail this modern technologic transportation create new opportunities for southern Taiwan. And bring lesson and suggestion for the future.
62

High speed rail : a study of international best practices and identification of opportunities in the U.S.

Rutzen, Beatriz 20 December 2010 (has links)
In the United States, passenger rail has always been less competitive than in other parts of the world due to a number of factors. Many argue that in order for a passenger rail network to be successful major changes in service improvement have to be implemented to make it more desirable to the user. High-speed rail can offer such service improvement. With the current administration’s allocation of $8 billion in its stimulus package for the development of high-speed rail corridors and a number of regions being interested in venturing into such projects it is important that we understand the factors and regulatory structure that needs to exist in order for passenger railroad to be successful. This study aims to review how foreign countries have developed and their railroad systems to identify key factors that have contributed to its successful implementation. An evaluation of the factors, such as organization structure, operation, administration, development and type of funding, that are common to each of these projects will used as performance measures to identify potential locations and opportunities for high speed rail projects in the U.S. Southwest region. / text
63

Opportunities and challenges for high-speed rail corridors in Texas

Carroll, Todd Davis 15 November 2011 (has links)
Texas features a growing economy and population. The state boasts a large and well-developed network of roads, freight railroads, and air facilities, which make the state a vital link in the movement of people and goods. However, as the state continues to grow in population and economic significance, these systems are straining to meet state, national, and even global needs. It is increasingly obvious to residents and state officials that Texas should consider implementing alternative modes of transport, including development of passenger rail, for which Texas currently lags behind many of its peer states. Passenger rail provides quantifiable benefits in displacing less energy-efficient and higher pollutant-emitting air and automobile modes while generating potential positive economic impacts and enhancing consumer choice and multimodalism. Conveniently, renewed national interest in rail has invigorated research measuring the applicability of passenger rail services to many different regions of the United States, with the possibility that future national transportation visions will include passenger rail as an essential element. This thesis seeks to clarify the potential for passenger rail specifically in Texas through comparison and contrast with other regions and nations in the midst of new national-level knowledge and the changing transportation opportunities and challenges facing the state. Some of the ideal characteristics of successful international passenger systems exist in Texas, including optimal city spacing and a well-established rail network, which have fuelled ongoing interest demonstrated by various system proposals for high-speed intercity transportation in Texas over the last four decades. Despite these characteristics, the state presents a number of barriers to rail transport rooted in low transit use coupled with generally lower density and ambivalent support from politicians and residents when officials present realities of eminent domain and land use changes. However, with revitalized national rail interest and new federal rail planning requirements, the state may yet be able to work through these challenges to exploit the opportunities the state possesses. / text
64

Geležinkelio vėžės geometrinių parametrų įtaka bėgių ilgaamžiškumui kreivėse / Influence of geometrical parameters of railway gauge upon rail durability on curves

Povilaitienė, Inesa 07 July 2004 (has links)
The aim of the research is to analyse the impact of geometrical parameters of gauge and displacement upon rail head side wearing on curves and present proposals to increase durability of rails on curves.
65

Two-dimensional separate-sided surface height profiling of lumber

Vadeboncoeur, Natalie Ivonne 11 1900 (has links)
Raw material accounts for a large proportion (approximately 75 percent) of a sawmill’s operating costs. However, about 15 percent of raw material ends up as low valued sawdust and planer shavings due to inaccurate cutting. Sizable financial benefits can be realized through maximizing conversion of raw material into valuable solid wood. Advanced process control in a sawmill can help achieve straighter cuts closer to final product dimensions and reduce loss of valuable raw material. A novel and practical method for enhanced process control in a sawmill is presented. A laser arrangement consisting of industrial point and line scanners is used to obtain a surface profile of the entire (two-dimensional) top and bottom surfaces of a lumber board. Each surface profile is independent of the other and free of data contamination caused by relative motions between the measured surface and sensors. Point scanners and line scanners simultaneously record 1-D and 2-D height data, respectively, along the length of the board. One-dimensional height data are used to identify relative motions through a mathematical technique based on linear inverse theory. Subtracting relative motion information from raw line scanner data provides an accurate 2-D surface profile. A second line scanner placed below the board can be used to obtain a separate 2-D profile of the bottom lumber surface. Separate-sided profiling is advantageous because typically a different saw or machine mills each side of a board. Thus, knowing the surface profile of each side of a board is crucial not only in diagnosing a deficiency in the milling process but also in determining the location of this deficiency. Results demonstrate that two-dimensional surface profiling can identify common surface defects such as step, washboard and knot tear-out with an accuracy of 0.3mm. Reproduction of each surface is rapid (approximately 0.2 seconds) and stable.
66

The Mechanical Pathway: Reactivating a Derelict Rail Corridor in Edmonton

Nally, Michael 25 November 2010 (has links)
This architectural thesis addresses a derelict urban rail corridor and the possibility of combining architecture and landscape to reactivate its latent potential as a dynamic seam in the urban fabric. Edmonton is a city built on a foundation of interconnectedness with the nation. Rail access has established the city as a staging hub for various industrial practices since the mid 19th century: import and export, agriculture, oil and gas, etc. As inner city rail access as been discontinued, parcels of rail land have been left as relics; nostalgic reminders of a formerly expansive arterial mechanical network, in turn connecting the city to a mechanical backbone spanning the nation. This architectural intervention will reactivate a piece of rail land in the northwestern part of downtown Edmonton by establishing a dynamic activity corridor around an energy-harnessing machine. / Apart from in-depth studies in renewable resource harvesting and climate, the thesis is driven by studies in rail and agricultural mechanisms, as well as existing post-industrial park typologies.
67

Geležinkelio vėžės geometrinių parametrų įtaka bėgių ilgaamžiškumui kreivėse / Influence uf geometrical parameters of railway gauge upon rail durability on curves

Povilaitienė, Inesa 09 July 2004 (has links)
The aim of the research is to analyse the impact of geometrical parameters of gauge and displacement upon rail head side wearing on curves and present proposals to increase durability of rails on curves.
68

Rail Platform Obstacle Detection Using LabVIEW Simulation

Tang, Shengjie January 2015 (has links)
As the rapid development of the rail transportation industry, rail transportation becomes more popular as a component of urban public transport systems, but the fallen obstacle(s) from the rail platform becomes the terrible hidden danger for the rail transportation. As an enclosed public transport systems, rail transportation creates gathered crowd both on board and on the platform. Although railway is the safest form of land transportation, it is capable of producing lots of casualties, when there is an accident.There are several conventional systems of obstacles detection in platform monitoring systems like stereo visions, thermal scanning, and vision metric scanning, etc. As the traditional detection systems could not achieve the demand of detecting the obstacles on the rail within the platform. In this thesis, the author designs a system within the platform based on laser sensors, virtual instruments technology, and image processing technology (machine vision) to increase the efficiency of detection system. The system is useful for guarantying the safety of rail vehicle when coming into the platform and avoid obstacle(s) on the rail fallen from the platform, having a positive impact on traffic safety to protect lives of people.The author used LabVIEW software to create a simulation environment where the input blocks represent the functionalities of the system, in which simulated train detection and fallen object detection. In this thesis, the author mainly focuses on fallen object detection. For fallen object detection, the author used 2D image processing method to detect obstacle(s), so the function is, before the rail vehicle comes into the platform, the system could detect whether there is fallen obstacle(s) on the rail within the platform, simultaneously categorize size of the obstacle(s), and then alarm for delivering the results.
69

Adhesion in the wheel-rail contact

Zhu, Yi January 2013 (has links)
To attract more customers and compete with other modes of transportation, railway transport needs to ensure safety, punctuality, high comfort, and low cost; wheel–rail adhesion, i.e., the transmitted tangential force in the longitudinal direction during driving and braking, plays an important role in all these aspects. Adhesion needs to be kept at a certain level for railway operation and maintenance. However, wheel−rail contact is an open system contact. Different contaminants can present between the wheel and rail surfaces, forming a third-body layer that affects the adhesion. Prediction of wheel–rail adhesion is important for railway operations and research into vehicle dynamics; however, this prediction is difficult because of the presence of contaminants. This thesis deals with wheel–rail adhesion from a tribological perspective. The five appended papers discuss wheel–rail adhesion in terms of dry conditions, lubricated conditions, leaf contamination, iron oxides, and environmental conditions. The research methodologies used are numerical modelling, scaled laboratory experiments, and field tests. The research objective is to understand the mechanisms of the adhesion loss phenomenon.  A numerical model was developed to predict wheel–rail adhesion based on real measured 3D surfaces. Computer simulation indicates that surface topography has a larger impact on lubricated than on dry contacts. Plastic deformation in asperities is found to be very important in the model. Ball-on-disc tests indicate that water can give an extremely low adhesion coefficient on smooth surfaces, possibly due to surface oxidation. Investigation of lubricated contacts at low speed indicates that oil reduces the adhesion coefficient by carrying a normal load, while adhesion loss due to water depends on the surface topography, water temperature, and surface oxidation. A field investigation indicates that leaves reduce the friction coefficient because of the chemical reaction between leaves and bulk materials. The thickness of the surface oxide layer was found to be an essential factor determining adhesion reduction. Pin-on-disc experiments found a transition in the friction coefficient with regard to the relative humidity, due to a trade-off between the water molecule film and the hematite on the surface. / <p>QC 20131031</p>
70

Two-dimensional separate-sided surface height profiling of lumber

Vadeboncoeur, Natalie Ivonne 11 1900 (has links)
Raw material accounts for a large proportion (approximately 75 percent) of a sawmill’s operating costs. However, about 15 percent of raw material ends up as low valued sawdust and planer shavings due to inaccurate cutting. Sizable financial benefits can be realized through maximizing conversion of raw material into valuable solid wood. Advanced process control in a sawmill can help achieve straighter cuts closer to final product dimensions and reduce loss of valuable raw material. A novel and practical method for enhanced process control in a sawmill is presented. A laser arrangement consisting of industrial point and line scanners is used to obtain a surface profile of the entire (two-dimensional) top and bottom surfaces of a lumber board. Each surface profile is independent of the other and free of data contamination caused by relative motions between the measured surface and sensors. Point scanners and line scanners simultaneously record 1-D and 2-D height data, respectively, along the length of the board. One-dimensional height data are used to identify relative motions through a mathematical technique based on linear inverse theory. Subtracting relative motion information from raw line scanner data provides an accurate 2-D surface profile. A second line scanner placed below the board can be used to obtain a separate 2-D profile of the bottom lumber surface. Separate-sided profiling is advantageous because typically a different saw or machine mills each side of a board. Thus, knowing the surface profile of each side of a board is crucial not only in diagnosing a deficiency in the milling process but also in determining the location of this deficiency. Results demonstrate that two-dimensional surface profiling can identify common surface defects such as step, washboard and knot tear-out with an accuracy of 0.3mm. Reproduction of each surface is rapid (approximately 0.2 seconds) and stable.

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