• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 316
  • 27
  • 14
  • 10
  • 5
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 439
  • 439
  • 439
  • 102
  • 92
  • 88
  • 71
  • 56
  • 55
  • 44
  • 41
  • 38
  • 37
  • 37
  • 31
  • 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.
111

Water management in China: the quantitative and qualitative approaches in the eastern route of the south to northwater diversion project

Chan, Che-san, Teresa., 陳芷珊. January 2013 (has links)
published_or_final_version / Architecture / Master / Master of Landscape Architecture
112

Prototype geographic information system for agricultural water quality management

Didan, Kamel. January 1999 (has links)
A prototype raster geographic information system (GIS) for agricultural water quality analysis was developed considering the farm as an aggregation of spatial units with homogeneous physical and management characteristics. A crop model that simulates the farm and environment response to different management scenarios was integrated with the GIS. The integrated GIS-model is then run on each homogeneous area. The results of crop yield and chemical leaching are geographically referenced for further display and analysis, and to serve as an input to the decision model. A decision model based on maximization of expected utility (MEU) was also integrated to help assess and evaluate the impacts of fertilizer application on the faun system and the environment. By using utilities for both crop yield and chemical leaching the model circumvents the issue of assigning a monetary value to the environment. Accommodating both the farmers' goals, in terms of higher yield and the well being of the environment, in terms of lower chemical leaching, the model computes the expected utility of each management scenario. The management practice with the maximum expected utility is then recommended. The integrated model was tested with an example of lettuce production in Arizona. Results were compared to published field reports, the model recommendation matched well with the field results. The prototype model was simple to use, and very well integrated, which makes it an alternative to the more complex and expensive coupling of commercial GIS and simulation models.
113

Evaluation of Ground-Water Monitoring Plan (WETS): Volume II - Appendices

Wilson, L. G., Martin, P., Lonergan, E. D. 01 November 1977 (has links)
Completion Report / Contract No. 26-235-816-40-2-050-0735 / Arizona Department of Health Services / Bureau of Water Quality Control
114

Modeling of Hydrologic Processes and Water Salvage Procedures in Semiarid Regions

Resnick, S. D. 12 1900 (has links)
Partial Technical Completion Report, Office of Water Resources Research, Project A-020-ARIZ / Grant Agreement No. 14-31-0001-3203 / Period of Investigation: 7/69-6/71 / Potential uses or reuses of salvageable waters in the Tucson region were examined, and costs and benefits related to such uses were evaluated. The quality of salvageable waters as determined in exploratory sampling was compared with water quality standards and criteria appropriate for agricultural, recreational and selected industrial uses. A tableau was then constructed which showed the type and estimated cost of conventional water treatment that would be required for each source-to-use combination. Finally, an estimate was made of unit net benefits to be anticipated from salvageable water input to these uses, and the net benefits were applied in several test calculations to illustrate mixed allocations of the various salvaged waters to the selected uses.
115

Removal of reactive dyes from dye liquor using activated carbon for the reuse of water, salt and energy.

Mbolekwa, Z. January 2007 (has links)
The removal of colour from effluent after dyeing of cellulosic fibres is a major problem due to the difficulty in treating such effluents by conventional treatment methods. Cellulosic fibres of a specific shade (colour) are produced by reacting the fibres with a mixture of reactive dyestuffs, salt and auxiliary chemicals. Reactive dye exhaustion to the fibre is about 80% i.e. 20% remains in the effluent; this is hydrolysed dye which cannot be reused for dyeing. The exhausted reactive dye bath together with first rinse represents 6 to 30 L effluent/kg of fabric and most of the colour and salt. The total water consumption for reactive dyeing ranges from 25 to 100 L effluent/kg fabric while the water consumption from total textile finishing ranges from 30 to 150 L effluent/kg fabric. Thus the concentration of the dye and salts are 5 times more concentrated when obtained at source. The use of activated carbon adsorption for the removal of colour from exhausted dyebath for the re-use of water, salt and energy has been studied. Four different commercial reactive dye chemistries and associated auxiliaries were tested and commercial activated carbon was used as an adsorbent. Different temperatures (20°C to 100°C), pH values (acidic, neutral, basic) and salt concentrations (50 g/L to 100 g/L) were evaluated and the high adsorption results were achieved when using high temperature, low pH (acidic) and high salt concentrations. The Freundlich adsorption parameters were obtained for activated carbon adsorption capacity and adsorption bond strength between reactive dyes and activated carbon. The overall removal of the reactive dye shades was 36% to 53% (based on colour in the effluent), salt recovery was about 94% to 97%, the water recovery ranged from 14% to 25% and energy savings of 17% to 32% could be achieved. Column adsorption test were performed at different temperatures and flowrates. The saturated activated carbon was regenerated and repeatedly used by elution with 1.0 M NaOH. The regenerated carbon was found to be effective up to 3 cycles of operations. A column system for treatment of reactive dyes using activated carbon was designed. The outcome of this study showed that treatment of reactive dyebath with activated carbon adsorption technique can allow re-use of water, salt and energy, thus enabling environmental improvements with a savings in salt, energy, water and treatment costs. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2007.
116

The effect of government regulation on planning costs in the federal water pollution control program of Public Law 92-500

Shaver, Michael R. January 1979 (has links)
The thesis explored the effect of government regulation on the cost of developing Facility Plans for pollution abatement facilities in Indiana. The study used cost data from nearly 300 sewage works projects across Indiana from 1968 to 1976. The cost of professional services for these projects was computed on a per capita basis for each fiscal year and fluctuations in cost were analyzed in light of regulatory changes.It was found that the effect of these regulatory changes was to escalate costs, especially in fees for projects in municipalities with less than 2,000 population. / Department of Urban Planning
117

Management and reuse of local water resources in residential developments in Adelaide /

Barton, Annette Unknown Date (has links)
This thesis reports on research undertaken into the integration of water reuse systems into medium to high density residential developments in the semi-arid climate environment of metropolitan Adelaide. The research has focused on maximising the reuse of local water resources for residential lifestyle purposes, through the incorporation of relatively simple water sensitive systems into subdivision type developments, where allotments are less than 500 sq.m. / The quantities and qualities of the local water resources- roof runoff, surface runoff and wastewater- are considered and a paradigm for their reuse presented in which each local water resource is linked with a residential use sector- in-house, ex-house and public space- in order to minimise treatment requirements. On the basis of this paradigm a water sensitive residential model (WSRM) is developed. This model constitutes a subdivision layout which incorporates reuse systems while endeavouring to keep water systems infrastructure to a minimum. / Following on from this, the feasibility of the WSRM has been investigated by applying it to three conventional residential developments within metropolitan Adelaide. These are located in the suburbs of Mawson Lakes, Taperoo and Aldinga Beach. The specific physical, topographic and hydrogeological conditions associated with each site have required a flexible approach to the application of the model; and while a unique arrangement has been found for each site, the basic elements of the WSRM have provided an underlying consistent theme across them all. / Water balance modelling using the WaterCress program has been undertaken for each site to gain an understanding of the level of 'water-self-sufficiency' that might be achieved with the WSRM. Modelling results have indicated that between 50-70% of domestic water needs can be satisfied using local water resources. / An economic assessment has been undertaken of the WSRM from the point of view of development costs. The water reuse systems have been designed and costed for each site. Development fees and charges have also been ascertained. This has enabled a comparison to be made with the costs and development charges of conventional type developments. It is concluded that while the costs of the WSRM developments were consistently greater than for conventional developments, the increasing need for developers to contribute to external works relating to infrastructure and the environment is altering the balance. When account is given to these external costs, 'reuse' developments are at least as equally viable as conventional developments. / The research has produced a practical model to build reuse systems into the fabric of the residential development, significantly reducing reliance on the mains water supply and creating more sustainable developments. It has also shown that the economics of such developments are changing for the better. / Adelaide, like other Australian capital cities, is presently beset with complex issues relating to water supply, wastewater and stormwater management. Better management and more sustainable use of the available water resources is needed; maximisation of water reuse and more efficient use of local water resources are becoming increasingly important. / The trend in Australia today is for medium to high density housing for inner city infill or redevelopment sites and for outer suburb greenfield sites. Water sensitive residential developments within Australia, which have incorporated water reuse, have generally been located in high rainfall areas (average rainfall above 1200mm/year) and/or where the average allotment size is greater than 600 sq.m.. Two exceptions to this are the New Haven village and Mawson Lakes developments in the greater Adelaide region, where the average rainfall is around 500mm/year. In these two cases, however, reuse accounts mainly for ex-house water uses; in-house water uses are essentially serviced by the mains supply with toilets being the only exception. / Thesis (PhD)--University of South Australia, 2005.
118

An exploratory study of industrial customers' perceptions of service quality of a privatized water company in Malaysia /

Ching, Lee Yow Unknown Date (has links)
Malaysia embarked on a privatization program in 1983. The overall aim was to relieve the financial and administrative burden of the government and to improve the efficiency and productivity of government enterprises. One of the sectors privatized was the water supply in Penang with the major objective of ensuring that the privatized water company, known as Penang Water Supply Corporation (PWSC), provides better quality services to its customers. The PWSC must attempt to satisfy its customers who must perceive that their needs are being met and to capture the voices of the customers in order to provide improved services. / This study assessed the suitability of the SERVQUAL instrument for measuring service quality in Malaysian water supply sector. It attemped to evaluate the quality of services provided by PWSC through the use of the SERVQUAL instrument to measure industrial customers' expectations and perceptions of the quality of service. SERVQUAL measures five service dimensions: tangibles, reliability, responsiveness, assurance and empathy. Expectations, perceptions and service quality scores were assessed and their significance interpreted. The research was conducted via a questionnaire survey. The results indicated that SERVQUAL to be an appropriate instrument to measure water supply service in Malaysia and three factors appear as dimensions of service quality. Analysis of the results revealed that industrial customers rated the service quality provided by PWSC as above average. Higher expectation than perception scores were recorded on all features of service quality indicating that customers expected a better quality of service from PWSC. An Extended Gaps Model of Service Quality was used to identify the factors contributing the service quality shortfalls. Strategies to improve service quality of PWSC were proposed. / Thesis (DBA(DoctorateofBusinessAdministration))--University of South Australia, 2004.
119

Laboratory and field evaluation of a lead smelter effluent in the upper Spencer Gulf, South Australia /

Ross, Kirstin. Unknown Date (has links)
Thesis (PhD)--University of South Australia, 2001.
120

Salinity and nutrients : growth and water use of aquatic macrophytes under controlled and natural conditions / by Kay Morris.

Morris, Kay January 1998 (has links)
Bibliography: leaves 217-229 / xvi, 229 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Salinity and eutrophication are regarded as significant threats to freshwater habitats - Addresses issues related to these problems. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1998?

Page generated in 0.1242 seconds