Extra High Voltage (EHV) transmission lines are designed to transfer large amount of power from one location to another. The length exposed to the environment is a major reason for occurrence of faults on the lines. A fault on a high voltage transmission line affects the stability of the overall power system, which sometimes leads to permanent damage of the equipment. Relays are developed and installed to protect the lines. The transmission line protection relays, in the industry, are based on the fundamental frequency components of the voltages and currents. These relays need at least one fundamental frequency cycle for performing the protection operation. Voltage and current traveling waves are generated when a fault occurs on the transmission line. The velocity of propagation of traveling waves is finite and the level of the waves decreases with increase in the distance traveled. Information about the fault can be obtained by analyzing the traveling waves. A few traveling wave techniques, which are based on analog signal processing, to protect transmission lines have been proposed in the past. Two digital techniques, which use traveling waves for protecting EHV transmission lines, are proposed in this thesis. The traveling waves are extracted from the modal voltages and currents at the terminals of the transmission line. The techniques identify and locate the fault by using the information contained in the waves. A power system was modeled in the Electromagnetic Transient Direct Current Analysis (EMTDC) and several cases were created by varying different parameters related to the fault, fault type, fault location, fault resistance and fault inception angle. The techniques were implemented in hardware and their performance was tested on data, generated from the EMTDC simulations. Some cases are discussed in the thesis. The performance of the digital techniques for protecting EHV transmission lines using traveling waves was confirmed to be satisfactory. The proposed techniques provide protection at speed and discriminate well between internal and external faults.

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Surrounded by the ocean, Taiwan is geographically positioned along the rim of the continental shelf and Deep Ocean. Owing to the terrain distribution and geological characteristics of this island, the coastline possesses abundant sand dune resources, which is considered priceless not only as the last natural defense system of the coast but also for the functions it performs in various aspects including tourism attractions, academic contributions, and biological environment. Since the scarcity of ground in Taiwan, high demand of land usage often endangers coastal dunes. Consequently, coastal dunes are facing serious issues regarding rubbish dumping, wastewater accumulation, manmade misuse, development of industrial estate, and barrier flat exploitation. Currently, Taiwanese government has not yet established an ordinance; neither have we advanced policy of coastal dunes protections, nor have we adopted the Seashore Pact. Barely a few enactments scattered in assorted pacts. The argument in this research is primarily centering on Taiwanese coastal dunes, ranging from the functions and values of sand dunes resources to international trends of sand dunes reservations. Furthermore, the purpose of this study is to deliberate real conditions and contemporary management mishaps of coastal dunes in Taiwan, in order to further strategize the sustainability and managerial implications.

Fachhochschule, Diplom-Arbeit des Studiengangs Bibliothekswesen--Köln, 2005. / Literaturverz. S. 87 - 95.

Dissertation--Juristische Fakultät--Ruprecht-Karls-Universität Heidelberg, 2003. / Bibliogr. p. 378-400.

Thèse de doctorat : Sciences de l'information et de la communication : Metz : 2007. / Thèse soutenue sur ensemble de travaux. Bibliogr. p.330-338. 13 Annexes p. 339-398.

Thesis (M.S.)--Wake Forest University. Dept. of Computer Science, 2004. / Includes bibliographical references (leaves 99-100).

Inaug.-Diss.--Jena.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 142-147). Available also in a digital version from Dissertation Abstracts.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 102-107). Also available in electronic version. Access restricted to campus users.