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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

Estimation of area and income elasticities of water demand in a number of cities and towns in Gauteng

Husselmann, M.L. 24 January 2012 (has links)
M.Ing. / Water demand prediction can be useful for future planning and has a significant economic effect on a city, town or suburb. There are numerous factors influencing water demand and therefore influencing the prediction thereof. The effect of each of these factors on the water demand is called the elasticity of that factor. The main aim of this study is to determine area and income elasticities of demand. This will enable the reader to predict water demand by taking stand size (area) and income into account. The stand value of each user was used as a surrogate for the income of that user. Another aim of this study is to compare average water demands for different cities and towns in Gauteng, South Africa with each other. Over 190 000 users' data were used for this study.
22

Optimalizace nákladů vodního hospodářství při výstavbě / Optimization of water management costs during construction

Kramárová, Annamária January 2019 (has links)
In the theoretical part, I mentioned the project management of buildings and the construction of prices in construction. In the next section I have described the building site and its water supply requirements. Finally, I have dealt with the cost of water and its consumption. The aim of the thesis was to analyze the influence of water prices on the cost of construction. I transferred this analysis to the model building in the practical part of the thesis. I determined the water consumption during construction, and then I analyzed the impact of the change in water prices on the construction cost.
23

Consumptive Use of Water by Major Farm Crops in the Milford District of Utah

Calder, Glen H. 01 May 1953 (has links)
Irrigation water supplies in the arid West have become limited, yet the area of irrigable land is still extensive. To realize the more efficient use of the available supply, or for planning new irrigation projects, studies are needed to determine how much water is consumptively used by farm crops and native vegetation.
24

Socio-economic and physical development influences on water use in Barbados

Suchorski, Alicia. January 2009 (has links)
No description available.
25

Assessment of Selected Sustainability Aspects of Biodiesel Production: Water and Waste Conservation

Tu, Qingshi 11 October 2012 (has links)
No description available.
26

Estimating domestic outdoor water demand for residential estates

Du Plessis, Jacobus Lodewikus 04 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The outdoor water consumption of residential properties is a major contributor to the seasonal fluctuation of the overall water consumption of these properties. The estimation of the relating outdoor water demand has become valuable to property developers and planners alike. This could enable designers to optimise designs of water distribution networks and assist in water resource planning and gaining legislative approvals. For the purposes of this study the outdoor water-use components were mathematically defined and combined to develop an outdoor water-demand model. In order to evaluate the results of an outdoor water demand model on a monthly temporal scale it was necessary to develop a proxy outdoor water consumption evaluation method based on the metered monthly consumption of residential properties. The method entailed verifying that the generally non-seasonal indoor water consumption as a function of the winter water consumption. This entailed analysis of the total monthly, indoor and outdoor water consumption data adopted from a noteworthy North American water end-use project. The indoor water consumption estimated in this manner could then be subtracted from the overall monthly water consumption to obtain estimated monthly outdoor water consumption data. The estimated outdoor consumption could be compared with the simulated outdoor water demand, as described by the model. The parameters that formed part of the mathematical outdoor water demand model were formulated from data available for residential estates, where conditions such as types of vegetation, irrigated area and size of pool could be prescribed in a constitution, usually instituted by a home owners association. The data was derived from one estate located in the Western Cape Province of South Africa. The mathematical model was simulated using the Monte Carlo method and the @Risk software. Three residential estates located in South Africa were subsequently modelled. Additionally, the model was employed to estimate outdoor water demand for houses located in Northern America for verification purposes. The Monte Carlo simulations of the outdoor water demand model presented in this study yielded realistic results when compared with the proxy outdoor consumption figures as well as the metered actual outdoor water consumption data analysed. The peak monthly outdoor water demand estimation results were particularly close to the consumption data. This study serves as a baseline for further research into outdoor water demand. Research into the effects of water restriction and conservation potential could follow from this work, especially in today’s environmentally conscious society. / AFRIKAANSE OPSOMMING: Die buite waterverbruik van residensiëel eiendomme dra grootliks by tot die seisoenale fluktuasie van die algehele water verbruik van hierdie eiendomme. Die beraming van die dienooreenkomstige buite wateraanvraag kan waarde toevoeg vir eiendomsontwikkelaars and beplanners, indien dit ontwerpers kan instaat stel om water verspreindingsnetwerke te optimeer en te help met water hulpbron beplanning en wetlikke goedkeurings. Vir die doeleindes van hierdie studie is die buite waterverbruik komponente wiskundig gedefinieër en gekombineer om ‘n buite wateraanvraag model te ontwikkel. Ten einde die resultate van ‘n buite water aanvraag model op ‘n maandelikse tydskaal te evalueer, was dit nodig om ‘n benaderingsmetode te ontwikkel, gebaseer of die gemeterde maandelikse water verbruike gebruik. Die metode behels dat die data, verkry van ‘n bekende Noord-Amerikaanse water eindverbruikprojek, van die algmeen nie-seisoenale binneshuise water verbruik vergelyk word met die maandelikse winter water verbruik. Derhalwe kon die binneshuise waterverbruik wat op hierdie manier beraam is afgetrek word van die algehel maandelikse waterverbruik om die maandelikse buitewater verbruik te beraam. Die beraamde buitewater verbruik kon sodoende vergelyk kan word met ‘n gesimuleerde buite wateraanvraag soos beskryf deur die gesimuleerde model. Die parameters wat deel uitgemaak het van die wiskundige buite waterverbuik model was gedefinieër uit data wat beskikbaar was vir residensiële ontwikkelings, waar voorwaardes soos plantegroei, besproeiingsarea of swembad grote dikwels voorgeskryf kan word in ‘n grondwet ingestel deur ‘n huiseienaarsvereniging. Die data wat in hierdie model gebuik word is hoofsaaklik afskomstig van ‘n landgoed geleë in die Weskaap provinsie, Suid-Afrika. Die wiskundige model was gesimuleer met behulp van die Monte Carlo metode en die @Risk sagteware. Drie residensiële landgoede geleë in Suid-Afrika was daaropvolgend gemodelleer. Daarbenewens is die model gebruik die buite watergebruik van groepe huise geleë in Noord-Amerika te beraam vir verifikasie doeleindes. Die Monte Carlo simulasies van die buite water aanvraag model van hierdie studie het realistiese resultate in vergelyking met die beraamde buite verbruike sowel as die werklike gemeterde buite water verbruiksdata opgelewer. Die piek maandelikse buite water aanvraag beramings resultate was veral vergelykbaar met die piek maandeliks waterverbruik data. Hierdie studie dien as 'n basis vir verdere navorsing in buite waterverbruik. Navorsing gefokus op die gevolge van water beperkings en bewaring potensiaal kan as aanvullende voordele van hierdie studie ontstaan, veral in vandag se omgewingsbewuste samelewing.
27

Geriamojo vandens poreikio pokyčių tendencijos / The tendencies in variations of water demand

Šukaitytė, Renata 29 May 2006 (has links)
The tendencies of changes in water consumption are discussed in this final master’s studies research during different periods. The object of the research was chosen the biggest Lithuanian cities such as Vilnius, Kaunas, Klaipeda, Panevezys and Siauliai, also the lower reaches of the Nemunas, the basins of the Venta-Lielupe and the Neris. The purpose of the research is to collect and to analyze the data about the water consumption and its tendencies of changes and to do the analysis of factors, which influence water consumption. This research paper analyses factors, which could influence the increase or decrease of water consumption. These factors might be the decrease of production amount, increasing water tariffs, the establishment of water-meters, low incomes of citizens, old water-supply systems, which influence bad water quality for consumers. Whereas designed water-supply do not match current standards of water consumption, water is held there for too long and this could influence connecting new water consumers. However at present land’s economy revives, the GDP is increasing and so the incomes of citizens increase too, which influence the increasing standards of water consumption, although they have not reached the level of the standards in 1989-1990. Analyzing statistical data about water consumption there was looked for a connection between the amount of consumed water and unemployment. Also analyzing the dependence on middle income and the level of water... [to full text]
28

Waterlisensiëring en waterprysbeleid in die nuwe waterwet

Joubert, Gerhardus Francois 14 September 2012 (has links)
M.A. / That South Africa is experiencing a water management crisis, is a fact that cannot be ignored. Although water supply departments and agencies are doing their best under the complex and demanding circumstances and have many examples of successful water projects to show for their efforts, inefficiency, unfairness and unsustainability still characterise much of the use and management of water and resources. This makes satisfying society's growing demand for reliable and legitimate water allocation extremely difficult. Groundwater is usually regarded by consumers as "private" water to be used as they please. Excessive use by such consumers of a borehole may lower the water table and reduce the amount of useable water for other consumers dependant on the same source. Some farms of land use, utilising a larger portion of available rainfall, for example commercial forestry in mountainous areas, reduce runoff into streams lower down, hampering the development potential of downstream areas. Other activities such as agriculture, mining and domestic uses, lower the quality of surface and underground water, making it unsuitable for use. Being such a scarce commodity, water should be used in the most efficient and beneficial way possible for every one in South Africa. In essence this means that all water used must be priced in accordance with its real economic value. The Water Act of 1998 is clearly based on an economic approach to bulk water tariffs. This means allocating water with the aid of water usage rights which are well defined, legitimate and non-discriminatory. The new water Act proposes a water licensing and pricing policy to achieve this goal. In striving for the economic goal, the ideal of sustainability of water management for future generations will become a reality. This study discusses the shortcomings of the previous water legislation as well as the replacement thereof with a more equitable and accessible water act. The study also contains comments on the possible shortcomings with the feasibility of some of the provisions of the new act, such as a conflict of interest that may develop, as well as possible preventive measures that should currently be undertaken to try and eliminate future problems.
29

Household Water Demand and Land Use Context: A Multilevel Approach

Breyer, Elizabeth Yancey 04 April 2014 (has links)
Urban water use arises from a mix of scale-dependent biophysical and socioeconomic factors. In Portland, Oregon, single-family residential water use exhibits a tightly coupled relationship with summertime weather, although this relationship varies with land use patterns across households and neighborhoods. This thesis developed a multilevel regression model to evaluate the relative importance of weather variability, parcel land use characteristics, and neighborhood geographic context in explaining single-family residential water demand patterns in the Portland metropolitan area. The model drew on a high-resolution panel dataset of weekly mean summer water use over five years (2001-2005) for a sample of 460 single-family households spanning an urban-to-suburban gradient. Water use was found to be most elastic with respect to parcel-scale building size. Building age was negatively related to water use at both the parcel and neighborhood scale. Half the variation in water use can be attributed to between-household factors. Between-neighborhood variation exerted a modest but statistically significant effect. The analysis decomposed household temperature sensitivity into four components: a fixed effect common to all households, a household-specific deviation from the fixed effect, a separate extreme heat effect, and a land use effect, where lot size exaggerated the effect of temperature on water use. Results suggested that land use planning may be an effective non-price mechanism for long-range management of peak demand, as land use decisions have water use implications. The combined effects of population growth, urbanization, and climate change expose water providers to risk of water stress. Modeling fine-grain relationships among heat, land use, and water use across scales plays a role in long-range climate change planning and adaptation.
30

Use of Water by Washington Navel Oranges and Marsh Grapefruit Trees in Salt River Valley, Arizona

Harris, Karl, Kinnison, A. F., Albert, D. W. 15 August 1936 (has links)
No description available.

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