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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.
311

Monitoring toxicity in raw water of the Cache la Poudre River and Sheldon Lake, Colorado, USA using biomarkers and molecular marker technology

Oberholster, Paul Johan. January 2005 (has links)
Thesis (Ph. D. (Microbiology)--University of Pretoria, 2005. / Includes bibliographical references. Available on the Internet via the World Wide Web.
312

An analysis of water resource conflict and cooperation in Oregon between 1990 and 2004 /

Fesler, Kristel J. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 94-99). Also available on the World Wide Web.
313

New Methods for Identifying Robust Long-Term Water Resources Management Strategies for California /

Groves, Donald G. January 2006 (has links)
Thesis (Ph.D.)--RAND Graduate School, 2005. / Includes bibliographical references. Also available on the internet via WWW in PDF format.
314

The Effects of the 2001-2002 Drought on Maine Surface Water Supplies

Schmitt, Catherine January 2003 (has links) (PDF)
No description available.
315

Simulation of post-earthquake water supply restoration calibration and application /

Brink, Susan A. January 2009 (has links)
Thesis (M.A.S.)--University of Delaware, 2009. / Principal faculty advisor: Rachel A. Davidson, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
316

Implicações da dinâmica de ocupação territorial nos recursos hídricos da bacia do Rio Corumbiara

Dal Magro, Eleonice de Fátima [UNESP] 08 April 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-08Bitstream added on 2014-06-13T19:21:51Z : No. of bitstreams: 1 dalmagro_ef_dr_rcla.pdf: 2332961 bytes, checksum: 2bc9db8e3a814c2c4165903b84ed2b89 (MD5) / A presente pesquisa propõe-se a contextualizar a dinâmica de ocupação territorial da Bacia do Rio Corumbiara no intuito de entender seus reflexos nas águas superficiais da bacia. Procedeu-se ainda a abordagem de outros componentes do meio físico local como o solo, cobertura vegetal, clima e geologia, uma vez que integrantes do meio e como tal devem ser considerados em processos que envolvam perspectivas de manutenção dos recursos hídricos mediante adoção de medidas mitigadoras de impactos ambientais, como ocorre na gestão participativa / This research propose to contextualize the dynamics of land-use of Corumbiara River Basin in order to understand its effects on surface water of the basin. There was also the approach of other components of the environment such as soil, vegetation cover, climate and geology, as members of the media and as such it should be considered in cases involving prospects for maintenance of water resources through adoption measures for mitigating environmental impacts, as in participatory management
317

Effective geyser management through intelligent hot water usage profiling

Catherine, Quinton Shaun January 2009 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009 / This study presents an intelligent Hot Water Cylinder (HWC) usage profiling system to provide peak demand side management and improve HWC efficiency in a typical household. In this research HWCs will be referred to as geysers. Research was done into various techniques available to improve energy efficiency in South Africa, as well as the different sectors South Africa's electricity supplier, Eskom, has highlighted where improvements in energy efficiency can be made. From this it was decided to refine the scope of the project to the residential sector, and more importantly geyser. A typical geysers operation and power consumption was researched and analysed to determine where efficiency improvements could be made. A system was required that would reduce the amount of energy consumed by the geyser, and provide the consumer with hot water at the same time. Based on the research it was decided to design a profile based geyser controller. The profiling system comprised of a PIC microcontroller, four digital temperature sensors and a time keeper used to determine individually based hot water usage profiles for the home. The profile was based on three parameters, namely the frequency (repetitiveness) of hot water being drawn, the length of the draw period, and the time of day when the water was drawn. Once the profile had reached a 90% accuracy, the profile implemented itself. Based on the profile, the controller then regulated the temperature of the geyser according to the demand of the household, without manual intervention. If the household's routine were changed, the profile would adapt itself accordingly. The controller is therefore fully intelligent and continues to refine the profile on a day to day basis. By introducing the profile based controller, the monthly average geyser temperature was reduced, reducing the amount of standing losses, which in torn reduced the total amount of energy consumed by the geyser. The profile controller was designed to aid in the reduction of the energy demand of geysers on the power grid. This will benefit both the consumer as well as Eskom, as Eskom will have a reduced power load, and the consumer will have a reduced electricity bill. The results of the experiments are shown, as well as a comparison between calculated versus measured results, to justify the accuracy of the calculations.
318

The historical archaeology of post-medieval water supply in Oxfordshire

Hind, Jill January 2014 (has links)
Surprisingly, clean mains water has only been universally available to the population of Oxfordshire since the second half of the 20th century. This thesis explores the different methods by which water was obtained between the end of the medieval period and the establishment of the contemporary water companies; it shows how archaeological remains can inform understanding of how different groups lived and interacted during that period. It attempts for the first time to catalogue water supply features within the county, having 910 entries to date. Patterns emerging from the data have been used to suggest themes for further study. Statistics and GIS mapping have demonstrated that the availability and quality of water, including the incidence of early holy and healing wells, are dominated firstly by geology and then by differences between the social classes and between urban and rural areas. Themes explored include the relationship between water and disease, whether water supplies differ between ‘open’ and ‘closed’ parishes, the evolution of holy wells into spas, water in leisure activities, its association with memorials and changing attitudes to hygiene. The thesis also examines the various designation systems in place for protecting historic monuments, the level of recording of water features on local and national lists of monuments and how appropriate this framework is for helping the conservation of a valuable resource.
319

A case-control study of bloody diarrhoea transmission in the Morifi, Holy Cross, Mohalinyane and Liphiring health centers catchment areas in Lesotho, 2003

Nkonyana, John Pontia 13 June 2005 (has links)
Lesotho is experiencing a problem of seasonal bloody diarrhoea outbreaks that occur in the southern districts of the country. Usually large proportions of the meagre resources are used to combat such outbreaks. Measures have been taken to provide water and improve sanitation for the commonly affected communities. However, the problem has continued unabated. There was therefore, a need to isolate factors that are associated with the transmission of bloody diarrhoea among the communities in the Moriti, Holy Cross, Liphiring and Mohalinyane health centres where bloody diarrhoea is prevalent. In this study, 145 cases of bloody diarrhoea and 269 controls were selected from the four health centres. Cases and controls were selected from subjects who were seen in the health centres during the period of December 2002 to February 2003. All available cases were selected whereas controls were selected by systematic sampling. The study examined environmental factors such as water source, waste and refuse disposal and hygiene practices. Binary logistic regression was used to estimate the effects of several exposures on bloody diarrhoea. The model showed maintenance of the boreholes to be the most important variable. The Odds ratio among people who experienced unavailability of water was 3.88 greater, among children who do not wash hands the odds ratio was 4.66 higher. Among subjects who ate bread in January the Odds ratio was 1.45 more and among subjects who had someone with bloody diarrhoea in the household the Odds ratio was 2.60 greater. / Dissertation (MSc)--University of Pretoria, 2005. / School of Health Systems and Public Health (SHSPH) / MSc / Unrestricted
320

The economics of seemingly abundant resource : efficient water pricing in Vancouver, Canada

Renzetti, Steven January 1990 (has links)
Current North American water pricing practices are inefficient because they are based on average utility expenditures rather than marginal costs and because they typically neglect factors such as the cyclicity of demands, the time of consumption and the value of the water resource. Despite strong criticisms of these practices (Hirshleifer, DeHaven and Milliman, 1960; Pearse, 1985) and the presence of well articulated theoretical models of efficient pricing alternatives (eg., peak-load pricing) no empirical study has been done to document the magnitude of the efficiency gains from altering water prices. A simulation program computes the impact upon a representative water utility's output and deficit and upon aggregate consumer surplus of a move from current practice to efficient prices. The program is based on the estimated costs of supply and demand for water for the city of Vancouver, Canada. A time series of quarterly observations for the period 1975-1986 is used to estimate short and long run marginal costs. The estimated cost structure of the utility is also used to test for optimal employment of its fixed factors: water in storage and capital. Cross-sectional data sets are used to estimate market demands for residential and industrial users. The estimation results indicate that long run marginal cost exceeds short run costs by a large margin and that there is some evidence of over-capitalization by the utility. Water demands are seen to be inelastic for indoor and outdoor residential consumption but are elastic for industrial consumption. Simulation results show that a move to seasonally differentiated pricing (with an annual charge calculated to recoup the resulting deficit) raises aggregate surplus by approximately 4%. Conversely, a move from current practice to Ramsey prices leads to a decrease in aggregate consumer surplus of approximately 13%. / Arts, Faculty of / Vancouver School of Economics / Graduate

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