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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.
221

Estimation of E. coli Concentrations from Non Point Sources Using GIS

Mckee, Kyna 2011 August 1900 (has links)
When developing a Watershed Protection Plan (WPP) or a Total Maximum Daily Load (TMDL), it is often difficult to accurately assess the pollutant load for a watershed because not enough water quality monitoring data are available. According to the Texas Commission on Environmental Quality (TCEQ), there are 274 bacteria impairments in Texas water bodies out of 386 impaired water bodies. Bacteria water quality data are often more sparse than other types of water quality data, which hinders the development of WPPs or TMDLs. The Spatially Explicit Load Enrichment Calculation Tool (SELECT) was used to develop watershed protection plans for four rural watersheds in Texas that are impaired due to E. coli bacteria. SELECT is an automated Geographical Information System (GIS) tool that can assess pathogen loads in watersheds using spatial factors such as land use, population density, and soil type. WPPs were developed for four rural Texas watersheds: Buck Creek, Lampasas River, five sub watersheds of the Little Brazos River, and Geronimo Creek. A spatial watershed model was developed to simulate bacteria concentrations in streams resulting from non point sources using SELECT combined with a simple rainfall-runoff model and applied to the Geronimo Creek watershed. The watershed model applies a rainfall-driven loading function to the potential E. coli loads calculated by the output of SELECT. The simulated runoff volumes and E. coli concentrations from the model were compared to actual monthly E. coli data collected at two sampling sites near the outlet of a subwatershed. The results show how SELECT methodology was applied to each watershed and adapted based on stakeholder concerns and data availability. The highest potential contributors were identified and areas of concern were highlighted to more effectively apply best management practices (BMPs). The runoff volumes were predicted with very good agreement (E = 0.95, RSR = 0.21 to 0.22) for both sampling sites. The predicted E. coli concentrations did not agree with measured concentrations for both sites using eight different methods. The results indicate that the model does not include significant factors contributing to the transport of E. coli bacteria but can be modified to include these factors.
222

Stochastic modelling of rainfall and generation of synthetic rainfall data at Mawson Lakes /

Rosenberg, Kathrine Joan. Unknown Date (has links)
Mawson Lakes is a new suburban housing development, situated 12 kms from the city of Adelaide in South Australia. The developers, the Mawson Lakes Joint Venture (MLJV), and the local council, the City of Salisbury, intend to capture all stormwater entering the site and recondition all wastewater. The water will then be supplied to residents and businesses for non-potable usage. Modelling the behaviour of the Mawson Lakes catchment under extreme conditions such as drought and prolonged periods of high rainfall will allow the project team to determine optimal water management strategies for the catchment. -- abstract / Thesis (PhDMathematics)--University of South Australia, 2004.
223

Modelling the flow regime of arid zone, floodplain rivers

Costelloe, Justin Francis Unknown Date (has links) (PDF)
The requirements of ecological studies and water resource management plans are driving demand for hydrological models of the rivers of the arid zone. Knowledge of the hydrology of Australia’s arid zone is poor, yet is critical in understanding the ecology of the region. The research presented in this thesis seeks to address some shortcomings in our understanding of the hydrology of the Australian arid zone. In particular, the research examines the requirements for modelling the flow regime of arid zone rivers, concentrating on the rivers of the Lake Eyre Basin (LEB). The LEB has exceptionally low annual runoff of 3.5 mm, its major rivers develop over extremely low gradients and are characterised by very wide floodplains and complex anastomosing flow paths in their mid to lower reaches. This research was driven by both a practical and theoretical impetus. Practically, hydrological data were required at the water body scale for a large number of sites across three river systems of the LEB, for use in a study, known as ARIDFLO, of the ecological responses to hydrological conditions. Because of the remoteness of these sites and the paucity of gauging stations on these rivers, modelling of the rivers was the only method for delivering the required discharge data. Theoretically, the challenge was set for creating hydrological models for some extraordinarily complex river systems, in terms of their size, catchment characteristics and flow regime variability. (For complete abstract open document)
224

Application and verification of several rainfall-runoff models in Hawaii

Murashige, Jo Ann Emi. January 1983 (has links) (PDF)
Thesis (M.S. - Hydrology)--University of Arizona, 1983. / Includes bibliographical references (leaves 113-115).
225

Variations in low altitude circulation and rainfall over Australasia during the southern hemisphere summer monsoon regime /

Allan, Robert J. January 1983 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, 1983. / Includes bibliographical references (leaves 320-343).
226

A compendium of Virginia hydrololgy /

Yang, Yung-Chi, January 1962 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute, 1962. / Vita. Abstract. Includes bibliographical references (leaf 82). Also available via the Internet.
227

Geochemical characterization of coastal precipitation: Natural versus anthropogenic sources.

Wadleigh, Moire Anne. Kramer, J. R. Schwarcz, H. P. Unknown Date (has links)
Thesis (Ph. D.)--McMaster University (Canada), 1989. / Source: Dissertation Abstracts International, Volume: 62-13, Section: A, page: 0000.
228

Stochastic generation of daily rainfall for catchment water management studies /

Harrold, Timothy Ives. January 2002 (has links)
Thesis (Ph. D.)--University of New South Wales, 2002. / Also available online.
229

Spatio-temporal hidden Markov models for incorporating inter-annual variability in rainfall

Frost, Andrew James. January 2004 (has links)
Thesis (Ph. D.) -- University of Newcastle, 2004. / School of Engineering. Discipline of Civil, Surveying and Environmental Engineering. Includes bibliographical references (leaves 205 - 217). Also available online.
230

Stochastic modeling of rainfall processes a Markov chain-mixed exponential model for rainfalls in different climatic conditions /

Hussain, Arshad, January 1900 (has links)
Thesis (M.Eng.). / Written for the Dept. of Civil Engineering and Applied Mechanics. Title from title page of PDF (viewed 2008/05/13). Includes bibliographical references.

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