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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.
21

Performance-based payments for conservation experience from a water quality field experiment /

Maille, Peter J. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains ix, 169 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 122-132).
22

Water conservation planning : developing a strategic plan for socially acceptable demand control programs /

Helmle, Samuel F. January 2005 (has links)
Thesis (M. P. A.)--Texas State University-San Marcos, 2005. / "Spring 2005." Includes bibliographical references (leaves 70-73).
23

An assessment of public participation in the South Central Texas Water Planning Group /

Barron, Wendy. January 2006 (has links)
Thesis (M. P. A.)--Texas State University-San Marcos, 2006. / "Summer 2006." Includes bibliographical references (leaves 84-86).
24

Water conservation through energy conservation

Nyathi, Nongezile Sibhekile 28 August 2007 (has links)
South Africa is one of the driest countries in the world and rivers and dams are the main source of water. The continuous pollution of the rivers and streams as well as the growing demand for water has led to stringent environmental regulations to limit the consumption of water as well as to set the acceptable contamination levels of water before it is discharged to the main water cycle. Various techniques have been used to address the issue of the usage and contamination of water in industry. In recent years, Pinch Analysis has been extended to cooling water systems design following its success in heat exchanger networks (HENs) and mass exchanger networks (MENs). The most significant work on cooling water network design was developed by Kim and Smith (2001) where a graphical methodology for designing cooling water systems was developed. Research on cooling water networks was necessitated by the need to optimize the amount of cooling water used in process industries. It is always important to conserve water as well as reduce the amount of contaminated water that is discharged to the main sources of water. In this study, the consumption of water and effluent reduction opportunities in a nitric acid production plant at African Explosives Limited (AEL), Modderfontein, South Africa, was investigated. This investigation led to the development of a cooling water network design technique for systems with multiple cooling water sources. The results from this analysis have shown that there is potential to reduce the blowdown by 47%. Moreover, the cooling water used in the cooling water network could be reduced by 23% and freshwater makeup by 10%. / Dissertation (MEng (Chemical Engineering))--University of Pretoria, 2007. / Chemical Engineering / MEng / unrestricted
25

Land use planning using geographic information systems

China, Samuel Soita January 1993 (has links)
No description available.
26

Water and fertility management for crop production in semi-arid Zimbabwe

Nyamudeza, Phibion January 1998 (has links)
No description available.
27

Design guidelines for habitat reintroduction within agricultural landscapes: A demonstration study

Grant, David B. 13 December 2016 (has links)
In southern Manitoba, there is a significant need to reintroduce diverse, ecologically sound environments to redress serious events of watershed habitat loss and accompanying landscape deterioration. Soil erosion, water pollution, and declining wildlife populations are the results of current agricultural practices and policy. The adoption of ecologically sound farming and water management practices compatible with the environmental requirements of native plant and animal communities will restore stability to the local ecosystem, diversity and interest to the landscape and a stronger sense of place for people of the region. This study describes the methods for effectively reintroducing habitat as part of a farms drainage network and the positive effect this has on soil and water conservation, both of which ultimately stimulate increased agricultural production.
28

Estimating the Annual Water and Energy Savings in Texas A & M University Cafeterias using Low Flow Pre-Rinse Spray Valves

Rebello, Harsh Varun 2010 May 1900 (has links)
Improving the efficiency of a Pre- Rinse Spray Valve (PRSV) is one of the most cost effective water conservation methods in the Food Services Industry. A significant contributor to this cost efficiency is the reduction in the energy costs required to provide the mandatory hot water. This research paper estimates the potential quantity and dollar value of the water and energy that can be saved annually in Texas A&M University's dining services with the installation of low flow pre-rinse spray valves. The data collection was obtained from four of Texas A&M University's Dining Services facilities. The annual savings were estimated by contrasting the water consumption of the existing T & S Brass B 0107-M PRSVs with the latest and most advanced available low flow T and S Brass B 0107-C PRSV. The annual water consumption of the existing and new PRSVs were predicted by measuring an individual average flow rate for each and observing the number of hours per day the PRSV would be used. The observed and measured values were extrapolated to amount rates to determine cost savings. The dollar value was ascertained using the utility cost data recorded over a semester by the Facilities Coordinator of the Department of Dining Services. The findings of this study show that the water savings from a single PRSV could lead to an estimated annual saving ranging between 46% and 78% of the current operation cost. The T & S Brass B 0107-C PRSV is currently priced between $52- $60 per valve resulting in a payback period ranging between 1.5-6 months per valve. If every valve on campus was replaced, the University could reap a savings in the range of $ 5,400- $22,590 over the 5 year useful life of the valve, having initially invested less than $550.
29

Analytical methods and strategies for using the energy-water nexus to achieve cross-cutting efficiency gains

Sanders, Kelly Twomey 17 February 2014 (has links)
Energy and water resources share an important interdependency. Large quantities of energy are required to move, purify, heat, and pressurize water, while large volumes of water are necessary to extract primary energy, refine fuels, and generate electricity. This relationship, commonly referred to as the energy-water nexus, can introduce vulnerabilities to energy and water services when insufficient access to either resource inhibits access to the other. It also creates areas of opportunity, since water conservation can lead to energy conservation and energy conservation can reduce water demand. This dissertation analyzes both sides of the energy-water nexus by (1) quantifying the extent of the relationship between these two resources and (2) identifying strategies for synergistic conservation. It is organized into two prevailing themes: the energy consumed for water services and the water used in the power sector. In Chapter 2, a national assessment of United States' energy consumption for water services is described. This assessment is the first to quantify energy embedded in water at the national scale with a methodology that differentiates consistently between primary and secondary uses of energy for water. The analysis indicates that energy use in the residential, commercial, industrial, and power sectors for direct water and steam services was approximately 12.3 quadrillion BTU or 12.6% of 2010 annual primary energy consumption in the United States. Additional energy was used to generate steam for indirect process heating, space heating, and electricity generation. Chapter 3 explores the potential energy and emissions reductions that might follow regional shifts in residential water heating technologies. Results suggest that the scale of energy and emissions benefits derived from shifts in water heating technologies depends on regional characteristics such as climate, electricity generation mix, water use trends, and population demographics. The largest opportunities for energy and emissions reductions through changes in water heating approaches are in locations with carbon dioxide intensive electricity mixes; however, these are generally areas that are least likely to shift toward more environmentally advantageous devices. In Chapter 4, water withdrawal and consumption rates for 310 electric generation units in Texas are incorporated into a unit commitment and dispatch model of ERCOT to simulate water use at the grid scale for a baseline 2011 case. Then, the potential for water conservation in the power generation sector is explored. Results suggest that the power sector might be a viable target for cost-effective reductions in water withdrawals, but reductions in water consumption are more difficult and more expensive to target. / text
30

Water Management

Middleton, James E. 10 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

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