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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.
1

Reduced water consumption and related greenhouse gas emissions : A study of the effects of Uppsalahem’s watersavings campaign in 2013

Zisimopoulos, Dimitrios, Thor, Linnéa, Frisk, Malin January 2014 (has links)
The purpose of this project is to evaluate the effects of a campaign that Uppsalahem implemented in February 2013, in order to make their tenants consume less water. The result of the campaign is evaluated in terms of reduced water usage and reduced emissions of greenhouse gas related to the heating of the water through district heating. Four different residential areas in urban Uppsala, where Uppsalahem implemented their water saving campaign have been studied. All calculations are done in MATLAB. The results regarding water usage is presented in cubic meters and the greenhouse gas emissions are presented in terms of carbon dioxide equivalents. A sensitivity analysis of the data is performed in order to study natural occurring variances of water consumption over time. In order to determine which parameter has the greatest impact on reducing carbon dioxide emissions, a sensitivity analysis of the fuel mix used at the district heating power plant is made. The results show that there has been a reduction of water usage since after the campaign was implemented and the sensitivity analysis of the data indicates that there has been an especially large decrease in water consumption between the years 2012 and 2013. Further though, the results contain monthly irregularities in water usage in the different areas. This shows that the reduction of water consumption has not been temporally associated to the campaign, which indicates that the reduction might not be an effect of the campaign. Regarding carbon dioxide emissions, the sensitivity analysis indicates that the kind of fuel mix Vattenfall use at their district heating plant has a much greater impact than the individual water usage behaviors of the tenants.
2

THREE ESSAYS ON WATER POLICY DESIGN

Dawoon Jeong (15354697) 27 April 2023 (has links)
<p>  </p> <p>Irrigation water is crucial for agricultural production and farmers’ livelihoods in many regions of the world. Water scarcity, however, due in part to extended droughts and groundwater depletion, is putting ever-increasing pressure on regulatory agencies to implement water conservation policies, possibly hampering farmers’ livelihoods and food supply. It is therefore imperative to implement policies that allocate scarce water resources in the most efficient way, while allowing water buyers and sellers to benefit from trading. In this dissertation, I study the design of water policies that are in use for agricultural water management in many dry regions: markets, quotas, and water pricing. A key distinction among them is that water markets constitute a decentralized allocation mechanism, while the other policies are centralized. </p> <p>In my first two essays, I compare two prominent market designs, namely once-a-year trading (i.e., non-recursive design) and year-round trading (i.e., recursive design). I examine the effect of these competing market designs on efficiency and distributional outcomes. I do so by accounting for two unique characteristics of irrigation water markets: 1) farmers differ in the marginal valuation of water, and 2) water is thinly traded. In my first essay, I theoretically develop a 3-seller and 3-buyer trading model and show that a recursive design can hinder efficiency when traders differ substantially in their water valuations. This is because sellers greatly increase markups, which strengthens trading frictions. </p> <p>Theoretical predictions from essay 1 rest on rather strong behavioral assumptions – sellers and buyers are able to identify and play a rather complicated subgame perfect Nash equilibrium. But human subjects may deviate from these due to many reasons, including bounded rationality and off-equilibrium beliefs, among others. In my second essay, I conduct a laboratory experiment with human subjects to examine the extent to which they follow theoretical predictions, and the effects of their behavior on the relative performance of competing market designs. Experimental evidence shows that subjects do deviate from predicted equilibrium, particularly when agents are highly heterogeneous. As a result, I find that some of my theoretical predictions are reversed in the laboratory. In particular, the recursive design outperforms the non-recursive design because experimental agents behave much more competitively under the recursive design than predicted by my subgame perfect Nash equilibrium.</p> <p>In my third essay, I empirically compare the performance of quantity and price policies, as well as a hybrid to conserve water, using observational data from Mexican farmers. A fixed cap (the policy chosen by Mexican regulators) effectively limits water consumption, but the rigidity of the cap results in substantial welfare losses due to volatile weather patterns that induce drastic fluctuations in water demand. Consequently, I study two counterfactual policies, a price policy and a hybrid that combines quantity and price policies. I find that the hybrid policy performs very well relative to its pure counterparts because it provides an intermediate level of flexibility in water consumption, preventing large losses under anomalous weather. </p>
3

Development of a sustainability index for South African dwellings incorporating green roofs, rainwater harvesting and greywater re-use

Van Der Walt, Johannes Tinus 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: South African water service providers experience major problems with providing adequate water services to consumers. Water service providers in South African urban areas rely on traditional centralised infrastructure, such as bulk supply networks, to provide water services. Alternative supply and stormwater drainage methods should be encouraged to help mitigate these problems. The researcher thus aims to quantify the potential impact that three alternative methods may have on a given dwelling in terms of its dependence on traditional bulk water services. The three alternatives considered in this thesis are the construction of green roofs, rainwater harvesting and greywater re-use. An efficiency of dwelling water use index (EDWI) was developed during this research project. It was designed in such a way as to show what portion of municipal water services could be replaced within the given dwelling by using the proposed techniques. The final EDWI-rating is obtained by using the EDWI-software tool developed as a part of this research. The derived EDWI-rating ranges from 0 to 100, with a rating of 100 indicating a dwelling requiring only the removal of a portion of sewage by a municipality, but no external water supply. Such a dwelling would also not require any water from a municipal network to meet domestic demand and all stormwater from its roof would be utilised within the plot boundaries. Results presented in this thesis illustrate how different geographical regions require different system specifications to obtain optimal EDWI-ratings, thereby lowering their dependence on the respective municipal water services. Validation of the EDWI-system proved difficult as no similar index could be found during the literature review. It was therefore decided to benchmark the EDWI-system using three model dwellings with nine configurations producing a total of 27 analyses. The EDWI-system provides a conceptual foundation for sustainable water services to South African households in serviced urban areas. Future work could further improve the EDWI-system by testing its practical application so that it may be extended to act as a national barometer, used to compare decentralised water services in terms of sustainability. / AFRIKAANSE OPSOMMING:Suid-Afrikaanse waterdiensverskaffers ondervind groot probleme met die voorsiening van voldoende waterdienste aan verbruikers. Waterdiensverskaffers in Suid-Afrikaanse stedelike gebiede maak staat op tradisionele gesentraliseerde infrastruktuur, soos grootmaatvoorsienings netwerke, om waterdienste te verskaf. Alternatiewe voorsienings- en stormwater dreineringsmetodes moet aangemoedig word om hierdie probleme aan te spreek. Die studie poog dus om die potensiële impak wat drie alternatiewe moontlikhede kan hê op 'n gegewe woning in terme van sy afhanklikheid van die tradisionele waterdienste te kwantifiseer. Die drie alternatiewe moontlikhede wat in hierdie studie ingesluit word is die konstruksie van groendakke, reënwater oes en grys water hergebruik. 'n Huishoudelike water gebruik doeltreffendheids indeks (EDWI) is ontwikkel gedurende hierdie navorsingsprojek. Die indeks is ontwerp om aan te dui watter gedeelte van munisipale waterdienste deur die voorgestelde tegnieke vervang kan word. Die finale EDWI-gradering is verkry deur gebruik te maak van die EDWI-programmatuur wat ontwikkel is gedurende die navorsing. Die afgeleide EDWI- gradering wissel tussen 0 en 100, met 'n telling van 100 wat ‘n woning voorstel wat slegs die verwydering van 'n gedeelte van die riool deur die munisipaliteit vereis, maar wat geen eksterne watervoorsiening benodig nie. So 'n woning vereis dus geen water van ‗n munisipale netwerk nie, en alle stormwater van die dak word binne die erf gebruik. Resultate wat in hierdie studie voorgelê word illustreer hoe verskillende geografiese streke ander stelsel spesifikasies vereis om optimale EDWI-gradering te verkry. Die navorser kon geen indeks kry wat soortgelyk is aan die EDWI-stelsel om dit mee te vergelyk nie. Dit was gevolglik besluit om die indeks te standardiseer deur gebruik te maak van drie model huise met nege samestellings van alternatiewe, waardeur 27 ontledings ontwikkel was. Die EDWI-stelsel bied 'n konseptuele grondslag vir volhoubare waterdienste vir Suid-Afrikaanse huishoudings in gedienste stedelike gebiede. Toekomstige navorsing kan die EDWI-stelsel verder verbeter deur die praktiese toepassing te toets. Die stelsel kan uitgebrei word om ‗n nationale barometer vorm wat gebruik kan word om desentralisasie van waterdienste te meet in konteks van volhoubaarheid.
4

Soil Temperature Influence on Water Use and Yield Under Variable Irrigation

Wraith, Jon M. 01 May 1989 (has links)
The need for efficient use of water resources has increased the importance of optimum soil water usage in agricultural systems. Soil temperature has been shown to be important in influencing the early development of many plant species. Many agricultural regions have suboptimal soil temperature regimes for plant growth, and some cultural practices have been shown to reduce near-surface soil temperatures. The seasonal influence of soil temperature on soil water extraction and aboveground and belowground plant growth under variable irrigation was investigated at the USU Greenville Farm in Logan, UT. Soil surface mulches and buried heat cables were used to modify soil temperature. A line-source sprinkler system provided a gradient of water application. During 1987 yields were mainly influenced by irrigation. During 1988 greater soil temperature differences resulted in significant plant growth and yield responses. Soil water depletion corresponded to soil temperature treatments during the early part of the growing seasons. Depth of maximum soil water depletion was about 20 cm deeper for warm treatments. Water uptake rates of earlier-maturing plants in warm treatments were reduced later in the season, so that cumulative seasonal soil water depletion was similar for all temperature treatments. Although depth of rooting was somewhat greater under high than low irrigation during 1988, low irrigation treatments depleted soil water to greater depth. There was no interactive response of plant growth and yield or of soil water depletion to soil temperature and irrigation treatments. Modifications were made to a computer simulation model of the soil-plant-atmosphere system in order to more mechanistically simulate plant water uptake and to include influences of soil temperature on seasonal rooting growth and soil water extraction. The model adequately simulated both the pattern and magnitude of soil temperature influences on soil water depletion, and conclusions drawn from model simulations agreed with field observations during 1987 and 1988.
5

Combating Budgetary Complications from the Marcellus Shale: The Case for a Pennsylvania Gas Fund

Thompson, Daniel Ray 19 May 2013 (has links)
The relationship between shale gas development and budgetary and microeconomic externalities was studied. The extraction activity in the Barnett shaleformation provided a case study for assessing per-well highway infrastructure damage and water usage. The creation of a predictive model based upon the Barnett was applied to the Marcellus formation. The results showed support for the hypothesis that shale gas development creates negative externalities that amount to unfunded mandates and freerider problems for states and localities. Implications and policy solutions, including the case for a Pennsylvania natural gas fund, are discussed. / McAnulty College and Graduate School of Liberal Arts; / Graduate Center for Social and Public Policy / MA; / Thesis;
6

Minimering av resursanvändning för ett CIP-system : Undersökning med faktorförsök

Söderling, Linnea January 2018 (has links)
Syftet med detta examensarbete är att utforska möjligheten att minska resurssvinnet vid utförande av en så kallad clean-in-place-rengöring. Arbetet svarar på frågor gällande de möjligheter som finns att effektivisera rengöringsprocessen alternativt att minska medieförbrukningen genom att förkorta sköljtider. Den huvudsakliga metoden som arbetet baseras på är faktorförsök genom försökplanering. Detta är en metod för att strukturera försök med flera korrelerande faktorer. De faktorer som har förändrats med mål att göra resurseffektiviseringar är en minskning av lutlösningstemperatur för rengöring, prov av olika mängd tillsatsmedel i lutlösningen och en förkortad tid för avslutande kallvattensköljning. Analysen visar att godkända resultat för rengöring erhålls även efter genomförda förändringar. En stor del av arbetet fokuserar på förståelse av systemets uppbyggnad och funktion. Att återvinna spolvatten i högre grad och att använda en lägre lutkoncentration skulle vid vidare arbete kunna ge möjlighet att ytterligare minska resursförbrukningen. / The purpose of this degree project is to explore the possibility of reducing the use of resources in performing a so-called clean-in-place cleaning. The work answers questions about the possibilities that are available to streamline the process or to reduce media consumption by shortening rinse times in the cleaning process. The main method on which the work is based is factor attempts through trial planning. This is a method of structuring trials with several correlating factors. The factors that have been altered, with the goal of making resources use more efficient, are a reduction of the caustic temperature for cleaning, using different amounts of additives in the caustic solution and a shortened time for the last cold water rinse in the cleaning process. The analysis shows that approved results for cleaning are also obtained after changes have been made. A large part of the work has been focused on understanding the system's structure and function. Recycling waste water to a greater extent and using a lower caustic concentration could possibly allow to further reduce resource consumption.
7

"Eat cooked, drink boiled" - A study on Vietnamese household usage behaviour

Nghiem, Anna January 2018 (has links)
Vietnam is a country that is characterized by a dense river network, experiencing a rapid economic growth, and still faces challenges with supplying enough water for the residents due to increased pollution levels. With water being perceived as one of the most stressed resources today, there is a need of understanding water usage behaviour. To fill in the gap in knowledge and provide a better understanding of the attitudes and the perceptions of household consumption behaviour could be a key to water savings on local and global levels. This field study was carried out in Hai Phong, the third largest city in Vietnam, as the potential of generalizing the result to other fast-growing cities and urban areas of the country was identified. In order to reach an improved understanding of water usage behaviour, the field study was of multi-design nature and was conducted by combining semi-structured interviews, water-diaries and observations. The results show that water usage behaviour is strongly determined by interpersonal trust issues which in most cases lead to an excess water consumption. The lack of trust did however also generate a cautiousness in water treatment routines, which could turn into a water savings behaviour. Other factors that affect water usage behaviour were seasonal aspects and cultural traditions perceptions. Despite the interpersonal trust issues, the institutional trust proved to be greater than expected while the role of marketing and information-based messages proved to influence behaviour. Based on this, water authorities have the potential of encouraging behaviour changes in upcoming challenges.
8

Soil-water use and irrigation scheduling under fruit tree-turf alley cropping system in Hawkesbury Area

Hasnat, Abul, University of Western Sydney, College of Science, Technology and Environment, School of Environment and Agriculture January 2003 (has links)
Efficient use of irrigation and nutrients are becoming increasingly important in commercial orchards in the Hawkesbury area. Proper irrigation scheduling practices can help in the better use of irrigation water and reduce environmental impacts. Field experiments were conducted during February 1999 to June 2000 to understand soil-water use, and to evaluate farmer’s irrigation practice under an alley cropping system consisting of turf and stone fruits. The study was carried out at Atlas Farm, 3.5 km from the University of Western Sydney, Hawkesbury campus. The experimental site is a floodplain of the Hawkesbury River. The river flows within 1 km of the farm boundaries. The study was conducted under the farmer’s existing irrigation water and nutrient management practices. The main aims of the thesis were to study the movement and redistribution of soil-water and soil-moisture dynamics in the turf and stone fruit alley cropping system and to understand deep percolation losses and nitrogen leaching using the water balance approach. The study indicated that drainage occurred mainly after heavy rainfall and when there was rainfall for a few consecutive days. Thus irrigation application should be delayed if there is a likelihood of rain in a few consecutive days to prevent loss of water due to deep drainage. Furthermore, the study showed irrigation scheduling was essential to reduce nitrate leaching in the field; that irrigation depths should be varied according to the stage of crop growth, and the proper timing of irrigation application could help reduce deep percolation and runoff losses. / Master of Science (Hons) (Agriculture)
9

Automated reading of high volume water meters

Ulyate, Jessica 03 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Accurate water usage information is very important for municipalities in order to provide accurate billing information for high volume water users. Meter reading are currently obtained by sending a person out to every meter to obtain a manual reading. This is very costly with regards to time and money, and it is also very error prone. In order to improve on this system, an image based telemetry system was developed that can be retrofitted on currently installed bulk water meters. Images of the meter dials are captured and transmitted to a central server where they are further processed and enhanced. Character recognition is performed on the enhanced images in order to extract meter readings. Through tests it was found that characters can be recognised to 100% accuracy for cases which the character recognition software has been trained, and 70% accuracy for cases which is was not trained. Thus, an overall recognition accuracy of 85% was achieved. These results can be improved upon in future work by statistically analysing results and utilizing the inherent heuristic information from the meter dials. Overall the feasibility of the approach was demonstrated and a way forward was indicated. / AFRIKAANSE OPSOMMING: Dit is belangrik vir munisipaliteite om akkurate water verbruikingssyfers te hê sodat hulle akkurate rekeninge aan hoë volume water gebruikers kan stuur. Tans besoek ’n persoon fisies elke meter om meterlesings te verkry. Dit is egter baie oneffektief ten opsigte van tyd en geld. Die metode is ook baie geneig tot foute. Ten einde te verbeter op hierdie stelsel was ’n beeld gebaseerde telemetrie stelsel ontwerp wat geïnstalleer word op huidig geïnstalleerde hoë volume water meters. Beelde van die meters word na ’n sentrale bediener gestuur waar dit verwerk word en die beeld kwaliteit verbeter word. Karakter herkenning sagteware word gebruik om die meter lesings te verkry vanuit die verbeterde beelde. Deur middel van toetse is gevind dat karakters herken kan word tot op 100% graad van akkuraatheid in gevalle waar die karakter herkenning sagteware opgelei is, en 70% akkuraatheid vir gevalle waarvoor dit nie opgelei was nie. Dus was ’n algehele herkennings akkuraatheid van 85% behaal. Hierdie resultate kan verbeter word in die toekoms deur die resultate statisties te analiseer en die inherente heuristieke inligting van die meter syfers te benutting. Ten slotte, in die tesis was die haalbaarheid van die benadering gedemonstreer en ’n weg vorentoe vir toekomstige werk aangedui.
10

Circular economy in the Nordic region – on the right path? : The effect of circular economy business practices on firms’ environmental performance

Horikx, Lotte, Beqiri, Bledar January 2017 (has links)
Over the last couple of decades, sustainability has gained importance in the business world, and a concept that has often been used as a prime example of how to deal with today’s environmental problems is circular economy. Even though the topic is relatively new, there has already been quite some debate about its actual advantages and disadvantages, and while there is as of yet no consensus, the majority argues that the application of circular economy practices will be beneficial for the environment. Which is exactly what this research has attempted to ascertain by looking at 78 firms from a wide range of industries yet all from the Nordic region, since this geographical area has been hailed repeatedly for their sustainability. This was done by performing a hierarchical regression analysis on the data in order to explore a possible relationship between the score of a firm on the benchmark of circular economy practices and its corresponding environmental performance, specifically energy consumption, water usage and greenhouse gas emissions. The hierarchical regression analysis showed a significantly positive relationship between a firm’s score on the benchmark of circular economy practices and its energy consumption, while controlling for firm size, industry, debt ratio,slack resources and country of origin, which was contrary to expectations. No such relationship was found between a firm’s benchmark score and their water usage, the same goes for greenhouse gas emissions. Nevertheless, this research has taken an important step in understanding the relationship between circular economy practices and a firm’s environmental performance, and in doing so has opened up new avenues to explore in terms of future research. While the Nordic region is on the right track, there is still a long road ahead.

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