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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.
441

Integrating railway track maintenance and train timetables

Albrecht, Amie January 2009 (has links)
Rail track operators have traditionally used manual methods to construct train timetables. Creating a timetable can take several weeks, and so the process usually stops once the first feasible timetable has been found. It is suspected that this timetable is often far from optimal. Existing methods schedule track maintenance once the best train timetable has been determined and allow little or no adjustments to the timetable. This approach almost certainly produces suboptimal integrated solutions since the track maintenance schedule is developed with the imposition of the previously constructed train timetable. The research in this thesis considers operationally feasible methods to produce integrated train timetables and track maintenance schedules so that, when evaluated according to key performance criteria, the overall schedule is the best possible. This research was carried out as part of the Cooperative Research Centre for Railway Engineering and Technologies. We developed a method that uses a local search meta-heuristic called 'problem space search'. A fast dispatch heuristic repeatedly selects and moves a track possessor (train or maintenance task) through the network; this results in a single integrated schedule. This technique generates a collection of alternative feasible schedules by applying the dispatch heuristic to different sets of randomly perturbed data. The quality of the schedules is then evaluated. Thousands of feasible solutions can be found within minutes. We also formulated an integer programming model that selects a path for each train and maintenance task from a set of alternatives. If all possible paths are considered, then the best schedule found is guaranteed to be optimal. To reduce the size of the model, we explored a reduction technique called 'branch and price'. The method works on small example problems where paths are selected from a predetermined set, but the computation time and memory requirements mean that the method is not suitable for realistic problems. The main advantages of the problem space search method are generality and speed. We are able to model the operations of a variety of rail networks due to the representation of the problem. The generated schedules can be ranked with a user-defined objective measure. The speed at which we produce a range of feasible integrated schedules allows the method to be used in an operational setting, both to create schedules and to test different scenarios. A comparison with simulated current practice on a range of test data sets reveals improvements in total delay of up to 22%.
442

Corporatization and privatization in Hong Kong : a case study of the highways department /

Lee, Wai-bun. January 1996 (has links)
Thesis (M.P.A.)--University of Hong Kong, 1996. / Includes bibliographical references.
443

Property development as a means of project finance for infrastructure project /

Chan, Chi-wah. January 1998 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1998. / Includes bibliographical references.
444

Harmonic simulation of traction system /

Lai, Tsz-ming, Terence. January 2000 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2000. / Includes bibliographical references.
445

Decomposed network and heuristic approach for rail transport crew scheduling system /

Chan, Cheuk-ho. January 1997 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 91-95).
446

The Taff Vale Desicion in British labor history

Moore, Joel Dayton, January 1965 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 129-133.
447

Congestion theory and railway traffic /

Lerz, Stefan. January 1996 (has links)
Thesis (doctoral)--Rijksuniversiteit Groningen), 1996. / In English, with summary in Dutch.
448

Decomposed network and heuristic approach for rail transport crew scheduling system

Chan, Cheuk-ho. January 1997 (has links)
Thesis (M.Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 91-95) Also available in print.
449

The competition between buses and the MTR in Hong Kong

Chan, Tat-tai. January 2002 (has links)
Thesis (M.A.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 73-74). Also available in print.
450

Qualitative assessment of a community college/business partnership BNSF railroad dispatcher training program at Tarrant County College /

Krueger, Beth Ann, Roueche, John E., January 2005 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: John E. Roueche. Vita. Includes bibliographical references.

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