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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

Reconstructing streamflow in the Upper Rio Grande River Basin

Correa, Karina Elena, January 2007 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
22

Remote monitoring and evaluation of a photovoltaic (PV) groundwater pumping system

Makhomo, Selbourne Rapoone January 2005 (has links)
Thesis (MTech (Technology))--Cape Peninsula University of Technology, 2005 / Potable water, and especially the accessibility to it, is an essential part of everyday life. Of particular note, is the challenge that residents of remote rural African villages face in order to gain access to this basic requirement. Specifically, the rural areas in the Northern Cape (Province north of Cape Town) region in South Africa is one such example that illustrates this problem very well. In order to address the requirements for drinkable water, various types of water pumping technologies have been used. Up to now, the two competing water pumping systems, diesel and photovoltaic (PV), have been the primary technologies deployed in selected sites in the Northern Cape. The manual data collection of water pumping system data in the Northern Cape is fraught with impracticalities such as travel costs and requirements for skilled personnel. Therefore, as a preliminary step to accelerate development and testing, a local experimental laboratory PV water pumping rig was set-up within the Department of Mechanical Engineering at the Cape University of Technology. A short-term analysis was performed over a period of three weeks on the rig and the experimental results indicated the following: array efficiency of 16.3%, system efficiency of 15.0% and an average system efficiency of 1.47%. However, the results do indicate that long-term monitoring of PV water pumping systems can be suitable in serving to determine dynamic system performance and system life cycle costs. The purpose of this project is two-fold - firstly, to present the results on the work done on the experimental PV system.
23

Adapting selected soil and water engineering technology to Thailand conditions

Weerasopone, Kraisorn January 1973 (has links)
Techniques were developed for the purpose of applying soil and water conservation structure designs utilized in the United States for use in Thailand. Design parameters currently being used in the United States were first studied and evaluated as to their development and application. The range of application of the various soil and water conservation structures were determined. This process included an evaluation of the soil types, land use, topography, and climatic factors in terms of their effect on the types of soil and water conservation structure designs to be utilized. Since the parameters may act separately or in various combinations, design limits are essential for each one. In the second step of the study, all available survey data applicable in characterizing these same parameters in Thailand were assembled and analyzed for each region. From this analysis, design ranges and the limits for each factor were estimated, based on the research and experience in the United States. Particular attention focused on the research of Beasley and the research compiled in the Engineering Field Manual. Finally, these estimated design values for Thailand's conditions were substituted in United States formulae. From these substitutions, other design procedures for model designs of several major engineering soil and water conservation structures were developed. / Master of Science
24

Defluoridation Of Drinking Water Using Activated Alumina

Kanwar, Lalita 08 1900 (has links) (PDF)
Excess fluoride (F-) in drinking water poses a health threat to millions of people around the world. In the present work, activated alumina (AA) has been used as an adsorbent. Data obtained from batch experiments were fitted to the (i) pseudo-first order, (ii) pseudo-second order, and (iii) Langmuir kinetic model. Model (ii) performed better than model (i), and fitted the data well. However, the rate constant for adsorption ka had to be varied as a function of the initial concentration of F- in the liquid phase c0. A more satisfactory approach is provided by Langmuir model, which fitted the data reasonably even though ka was independent of c0. Shreyas (2008) developed a model for the batch adsorption of F- onto porous pellets of AA. Some errors were detected in his computer program were corrected. The parameters of the model were estimated by fitting predictions to data. The parameter values suggest that the adsorption process is likely to be diffusion limited. Column experiments were conducted as follows. The pellets were soaked in deionized water for a time ts before they were loaded into columns. A feed solution having a fluoride concentration cf = 3 mg/L was fed to column and the concentration of F- in the exit stream ce was measured at regular intervals. Breakthrough was deemed to have occurred when ce exceeded the permissible limit (= 1 mg/L). Constant values of the bed height H, and the empty bed contact time tc were used in the experiments. The volume of treated water V, scaled by the volume of the bed Vb, varied strongly with the soaking time ts, with a maximum at ts = 24 h. To understand the possible reasons for this behaviour, XRD, FESEM, and FTIR were used to characterize the surface of AA. Though the concentrations of the surface hydroxyl groups may influence the adsorption of F-, FTIR studies show there is no direct correlation between V/Vb and the concentrations of these groups. The FESEM and XRD studies indicate that fresh AA consists mainly of boehmite, which gradually converted to gibbsite during soaking. For fixed values of H and tc, the dimensionless volume of treated water V/Vb was a maximum at D = 45 mm. This behaviour may be caused by wall effects for small values of D and by occurrence of quasi-static regions near the wall for large values of D. The cost of treated of water was Rs. 0.42/L. It decreased slightly to Rs. 0.37/L after one regeneration cycle, but increased to Rs. 0.41/L after two cycles. The volume of treated water after two regeneration cycles was 595 L/kg. The concentration of Al3+ ions ca in the treated water increased and exceeded the permissible limit of 0.2 mg/L as the number of regeneration cycles increased. The concentration of F- in regeneration effluent cre was in the range 32-70 mg/L. The effluent was subjected to solar distillation, leading to a distillate whose fluoride concentration F- was in the range 9-12 mg/L. The distillate can be discharged into the public sewers, as the permissible limit is 15 mg/L.
25

Discharge Estimations With Regression Analysis Using Basin Parameters And Gis Techniques

Pekpinarli, Hakan 01 June 2005 (has links) (PDF)
Discharge estimations at certain cross sections of streams are very important for hydrologic studies especially for designs. In this study, it is aimed to determine regional mathematical equations that represent annual and monthly average discharges at desired locations using basin characteristics obtained with Geographical Information Systems (GIS) techniques and regression analysis. Study area covers three river basins, which are Gediz, K&uuml / &ccedil / &uuml / k Menderes and B&uuml / y&uuml / k Menderes. The data used are Digital Elevation Model (DEM), monthly average discharges observed at stream gauging stations and monthly total precipitation data from the precipitation observation stations in the study area. Stream networks are delineated from DEM using a GIS software. The basin parameters obtained from DEM are drainage area, total river length, main channel slope, main channel length and mean basin slope. Precipitation amount is also included in the analyses as the sixth parameter to improve the results. Using these parameters annual and monthly average discharge equations are determined and the best equation for each month is found based on the adjusted coefficient of determination values and stepwise regression analysis. Three models, each representing a different basin and a general model that represents the whole study area are developed. The verification of the models is made using the discharges at the additionally chosen stations that are not included in the model development. An interface that acquires the drainage area for a certain cross section and estimates the discharge according to the desired regression equation is written using arc objects and visual basic programming language. At the end, regression analysis results of the models are assessed and interpreted.
26

Application Of The Map Correlation Method To The Western Blacksea Basin

Ergen, Mehmet Kayra 01 June 2012 (has links) (PDF)
Turkey is a developing country and its energy demand is increasing due to its growing population and industry. As a result, to fulfill this growing energy demand, Turkey is currently developing its unused hydropower potential, especially through small hydroelectric power plants (SHPPs). Estimation of annual electricity generation of a small hydropower plant strongly depends on streamflow data. In Turkey, there are a limited number of streamgaging stations so the estimation of streamflow at a potential SHPP location requires transferring streamflow time series from a reference streamgaging station to the ungaged basin. In order to determine daily streamflow time series for ungaged catchments, typically the nearest streamgaging station is chosen as the reference streamgaging station. However the distance between a reference streamgaging station and an ungaged catchment may not always be the most appropriate reference streamgaging station selection criterion. Archfield and Vogel (2010) proposed a new method called the Map Correlation Method (MCM) to select a reference streamgaging station to donate its observations to an ungaged catchment. MCM aims to identify the most correlated streamgaging station with the ungaged catchment. This new method is used at the Western Blacksea Basin in Turkey to select the best among possible reference streamgaging stations. The method proved to be promising / the most correlated streamgaging station for approximately one third of the study streamgaging stations are identified correctly by the MCM.
27

Analysis of the water distribution main replacement conundrum in Durban.

Scruton, Simon Robert. 15 September 2014 (has links)
The optimisation of the decision of when to replace water distribution mains is a complex task. There are numerous drivers in the decision making process (informed by financial data, performance data and water quality data) and hundreds of variables and performance indicators that can be considered when trying to reach an optimised decision. Most of the assets under consideration are buried and the internal and external pipe conditions are not easily assessable, forcing the Utility to rely on the available direct and indirect variables from which conclusions on the reliability of the mains are to be inferred. The cost of mains replacement is relatively low but the assessment cost, if carried out can be relatively high. The total value of a metropolitan distribution network typically runs into billions of rands but the impact of an individual pipe failure is generally low. The distribution network is comprised of many different pipe materials and components, of different pressure classes, made by different manufacturers, installed by numerous contractors with different skill levels under differing quality control regimens over many years. To add to this complexity, various parts of the network are operated at different static pressures and varying velocities. Some sections of the network are isolated more often than others and at times there can be large pressure surges that the network is subjected to by either the Utility or Consumer. These pressure surges are known to have a marked detrimental effect on the network. False markers also exist that can give rise to totally incorrect decisions and therefore performance data cannot be accepted at face value and needs to be scrutinised and cleansed to increase its reliability prior to being utilised in decision making process. This important step has been missed by much of the research carried out to date. In the Durban context, a further complication is caused by consumers tampering with the water mains and also not reporting leaks. This has a negative effect on the performance of the water main that can cause it to be flagged for replacement, but its replacement will not result in an increase in performance if the social issues are not resolved first. The aim of this research is to make recommendations on the methodology to be employed to improve network performance and thereby delay the point at which the water mains are to be replaced for as long as possible. These recommended activities will be carried out to remove false markers and improve upon the quality and reliability of the data available on the network performance. A further output is to make recommendations regarding the minimum data that can be reasonably collected and analysed in order to determine an optimised result. The recommendation of which mains should be targeted for replacement should result in the highest benefit for the utility as well as the consumers. By implication, this will result lowest long term capital and operational expenditure and thus the lowest long term tariffs charged to the consumers whilst complying with the water quality criteria and service level targets. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2012.
28

A hydroinformatic approach to basin/coastal water management /

Naoum, Sherif. Tsanis, Ioannis K., January 2003 (has links)
Thesis (Ph.D.)--McMaster University, 2003. / Advisor: Ioannis Tsanis. CD-ROM contains Appendices A-H (51 p.). Includes bibliographical references (leaves 297-307). Also available via World Wide Web.
29

Sustainable urban water systems : policy and professional praxis /

Mouritz, Mike January 1996 (has links)
Thesis (Ph. D.)--Murdoch University, 1996. / Thesis submitted to the School of Social Sciences. Includes bibliographical references.
30

Stochastic analysis of water supply systems including system hydraulics

Kretzmann, Hayley Ann 27 August 2012 (has links)
M.Ing. / Stochastic analysis of water distribution systems allow the performance of systems to be evaluated under more realistic conditions that involve both deterministic and probabilistic factors. A software package called Mocasim II has been developed to perform stochastic analysis on water supply systems. This allows the relationship between the reliability of the supply system and the capacity of its service reservoir(s) to be quantified using Monte Carlo analysis. In a Monte Carlo analysis the factors which influence the reliability of the system such as water demand, fires, and pipe failures are simulated stochastically over a long period of time. A reliability-capacity relationship is quantified by analysing the failure behaviour of different service reservoir sizes. A previous version of Mocasim used a simple mass balance model for calculating the flows in simple, linear distribution networks. Mocasim II extends the functionality of its predecessor by enabling the probabilistic modelling of more complex water distribution models. This was achieved by integrating the stochastic modelling technique into the Epanet hydraulic analysis software package. Mocasim II was designed using an object-oriented model which has various advantages such as ease of programme testing, upgrading and maintaining as well as minimum repetitive code and a logical structure. Additional capabilities of Mocasim II include the determination of probability distributions for network properties such as flow rate, pressure and water quality at any node in the network. This will assist in estimating the levels of service of a water supply system. This project focussed on developing sections of Mocasim II to be integrated with existing software such as Mocasim I, the Epanet hydraulic engine, OOTEN, and a random number generator. The software was tested thoroughly. This involved testing each class separately as well as applying it to a test case which is a simple network consisting of a source, reservoir and demand node. The theoretical background of the stochastic model has been investigated and various aspects discussed. Various case studies in Windhoek-Namibia, Mabeskraal-South Africa and an Epanet design example demonstrate the capabilities of the software and benefits of a stochastic analysis. A workbook to be used in addition to the software's help facility has been developed.

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