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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.
101

Essays on Women's Empowerment and Economic Development in Iran

Taghvatalab, Sara 31 August 2015 (has links)
This dissertation consists of three essays on women empowerment in Iran. In the first two chapters, we examine the impact of the rapid expansion of electricity to rural areas of Iran after the 1979 revolution on two important determinants of women's empowerment, fertility and female literacy. We use the timing of provision of electricity to villages to identify its impact on the child-woman ratio and the literacy rate of adult women and men. We use difference-in-differences (DID) method as well as instrumental variables (IV) to account for the potential endogeneity of electrification. Our findings for the impact of electricity on fertility is highly sensitive to the method of identification. The DID results imply that electrification lowers fertility whereas the IV estimates suggest the opposite. The results on literacy are consistent across estimation methods, both showing that electrification increases female literacy. In the third chapter, we focus on the role of education in the empowerment of women. The positive effects of education on female empowerment through lower fertility and greater labor force participation are well known. Female empowerment is also closely identified with greater participation in market work and access to an independent source of income. In the past two decades Iranian women have increased their education, lowered their fertility, but their labor force participation remains low. In this chapter we examine the role of education in the empowerment of Iranian women through their allocation of time between domestic work, child education, and market work. We find evidence that more educated women spend more time in market related activities and child education, but less in domestic work. The behavior of women in time allocation to market work and childcare exhibits similar patterns and both are quite different from house or domestic work. These findings are consistent with the hypothesis that education empowers women by increasing their ability to earn more income as well as through their ability to invest in the education of their children. / Ph. D.
102

Non-Uniform Copper Corrosion in Potable Water: Theory and Practice

Lattyak, Rebecca Marie 03 September 2007 (has links)
While it has long been known that water flow can influence non-uniform corrosion of copper pipe (Rushing 2002, Marshall 2004), it has never previously been considered a primary contributor to the problem. This work is the first to describe a fundamentally important phenomenon in aqueous non-uniform corrosion: flow electrification. A conceptual framework for flow electrification was developed from prior work on non-aqueous fluid flow in pipes, where the primary concern was prevention of electrical explosions. Thereafter, a series of experiments was aimed at monitoring flow electrification, quantifying its practical effects, and examining aspects of non-uniform copper corrosion in real situations. Under conditions with little or no flow, in a high pH and high chlorine water known to cause pinholes in copper pipes, while water chemistry influenced corrosion, non-uniform corrosion was not sustained. But when flowrates were higher, flow electrification contributed to severe and sustained non-uniform corrosion, with the most serious attack manifested in the first section of pipe that encountered the flowing water. The magnitude of flow electrification increased with chlorine concentration, pH and flowrate. Containers dosed with inhibitors such as zinc or phosphate experienced lower electrification, current, voltage, scale resistance, and corrosion potential measurements when compared to a control without an inhibitor. Additionally, systems dosed with inhibitors had reduced rate of chlorine decay, weight loss, pit density and/or maximum depth. Zinc orthophosphate had the largest positive impact on electrochemical measures of pitting. However, experimental studies suggested that if zinc orthophosphate was dosed to a system for a period of time, and dosing was then stopped, very serious pitting could occur. A practical case study seemed to strongly confirm this hypothesis in one system. The presence of sulfides caused the separation of anode and cathode along a pipe section, from electrification, to reverse relative to what was observed in the system with high chlorine and high pH. Below a certain level of sulfides, electrification ceased. It seems likely, based on measurement of electrochemical potential (Ecorr) in waters of this type as a function of sulfide concentration, that the onset of pitting would be associated with decreasing Ecorr with time. If so, the fundamental basis of tracking Ecorr rise with time to predict pitting propensity would be invalidated. Electrochemical noise programs were applied to try to differentiate between systems of low and high pitting propensity. Amplitudes of potential noise and current noise measurements drastically increased with the presence of sulfides or chlorine, confirming that tracking electrochemical noise may indicate the presence of a pitting agent. However, the electrochemical noise measurements are at best, an indirect indicator of copper pitting, and their interpretation is complicated by the co-occurrence of flow electrification. Attempts were made to apply these insights to a case study examining pitting in two real waters in Maryland and to examine the effects of orthophosphate, chlorination, chloramination and enhanced coagulation on copper pitting propensity. Tracking of Ecorr suggested that the control water (without phosphate) had the greatest pitting propensity. The free chlorine system with orthophosphate maintained Ecorr values below the control signifying that the presence of phosphate lowered the corrosion propensity. Waters with chloramine and phosphate had the lowest Ecorr values and also had the least variability in Ecorr due to the stability of the disinfectant. There is considerable ambiguity in the results, since the copper pipes exposed to the waters in question did not develop serious pitting over the several months of the study. / Master of Science
103

Développement méthodologique pour l'évaluation des performances et de la durabilité des systèmes de production d'électricité par gazéification de biomasse en milieu rural : Etude de cas au Burkina-Faso / Methodological development for performance and sustainability assessment of power generation systems based on biomass gasification in rural areas : case study in Burkina Faso.

Chidikofan, Grâce 21 December 2017 (has links)
Le but de cette thèse est de développer une méthodologie permettant d’évaluer les performances et la durabilité des systèmes de production d’électricité par gazéification de biomasse en milieu rural en pays en développement. Cette thèse propose un cadre méthodologique général qui décrit les démarches visant: (1) à définir les critères d’évaluation de performance, (2) à choisir les méthodes ou modèles d’évaluation des critères et (3) à choisir la méthode permettant d’analyser la fiabilité de l’évaluation. A partir de ce cadre méthodologique, une méthodologie d’évaluation des systèmes de production d’électricité par gazéification de biomasse en Afrique de l’Ouest est développée. Quatorze (14) critères d’évaluation sont définis en prenant en compte les quatre dimensions de la durabilité (technique, économique, environnemental, social). Des modèles sont élaborés pour l’estimation de chacun des critères considérés. Le modèle d’évaluation global est appliqué sur un projet de système de production d’électricité par gazéification de biomasse au Burkina Faso. Douze (12) configurations de système sont évaluées pour satisfaire les mêmes profils de charge. Les résultats de simulation ont permis d’identifier d’un point de vue de l’opérateur et des consommateurs, la configuration qui permet de valoriser au mieux la ressource en biomasse locale disponible avec un coût d’électricité abordable et qui offre à l’opérateur une flexibilité relative pour s’adapter aux évolutions de la demande en énergie électrique / This thesis aims to develop a performance assessment methodology of power generation systems based on biomass gasification in a rural area case in developing countries. The general methodological framework of this thesis is described in the approaches as follow: (i) defining performance assessment criteria, (ii) selecting methods or models for assessing the criteria, and (iii) choosing the method of analyzing the reliability of the assessment. Based on this methodological framework, a methodology for the assessment of electricity generation by biomass gasification systems in West Africa is developed. Fourteen assessment criteria are defined by taking in account technical, economic, environmental and social aspects. Models are developed for the calculation of each criterion considered. The models are then applied to carry out a performance assessment of the electricity generation by biomass gasification project in Burkina Faso. Twelve (12) system configurations are studied to satisfy the same load profiles. Simulation results allowed identifying from the point of view of the operator and the consumers the configurations which give better valorization of biomass available with an affordable electricity cost and which offer to operator a relative flexibility to adapt to changes in electricity demand.
104

The use of small scale hydroelectric power in South Africa, hydro and economic potential for rural electrification.

Reddy, Devan. 01 November 2013 (has links)
Small hydro generation refers to generating capacity of less than 10 MW with the most common being Run-of-River. In South Africa, the level of rural electrification is approximately 50 percent with most of the energy needs being met with biomass fuels. The purpose of this study was to investigate the hydropotential regions that were identified by Eskom and the Department of Minerals and Energy in 2002 and determine sites for small scale development for rural electrification purposes. Technical and feasible analyses were carried out in order to assess the applicability of this kind of energy generating system. The aim of this study was to consider the Free Basic Electrification policy and Solar Home Systems to assess the electrical demand of rural households and possible funding transfer scheme respectively. Furthermore, to formulate an appropriate methodology that can be used given the available data and resources currently available in South Africa. In total, six sites were identified and analysed in this paper, namely: (1) Berg River at gauge G1H013, (2) Mzimvubu River at gauge T3H008, (3) Orange River at gauge D1H003, (4) Mlambonja River at gauge V1H041, (5) Thukela River at gauge V1H002 and (6) Mkomazi River at gauge U1H005 which are in the Eastern Cape, Western Cape and KwaZulu-Natal Provinces. Flow gauge data were analysed in order to develop monthly mean Flow Duration Curves which were used to determine the design flow, power generation (through Power Duration Curve construction) and renewable energy potentially produced from each scheme. Costing functions were utilised in order to determine the initial capital cost of the system which was used to assess the project’s feasibility. In order to predict potential power output of the schemes, the streamflow and hydraulic head of the six rivers were assessed. The potential renewable energy production ranged from about 240 to 6060 MWh/year. Through this energy production, it was found between 165 and 10100 houses could be electrified depending on the electrical allowance provided. This significantly exceeds existing housing numbers. Costing bands ranged from 3 – 7 R/kWh which was high but within reason based on the community income and the transfer of the Solar Home Systems pricing policy. The results of this study provide a good foundation for future work in the estimation of hydropower potential in South Africa and will hopefully be a stepping stone to better estimation of both technical and exploitable hydropower potential for South Africa. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2012.
105

An investigation into using GIS in electrification and network planning in rural KwaZulu-Natal.

Barnard, Jennifer B. January 2006 (has links)
The South African Government has set a target of universal access to basic electricity by the year 2012. Free basic electricity is defined as the amount of electricity sufficient to provide basic lighting, media access, water heating and ironing with on-grid electricity; or basic lighting and media access for a non-grid system. Eskom Distribution, in conjunction with local municipalities, is responsible for the outstanding electrification predominantly in rural areas. In KwaZulu-Natal, mountainous terrain and scattered settlement patterns of communities complicate the achievement of this goal. This study was aimed at using GIS to address the urgent need to plan electrification, firstly by identifying areas that need electrification and secondly by prioritising those areas according to set principles. Electrification areas were effectively identified and prioritised from both a need and capability of supply aspect. The study then aimed at designing the shortest networks from the grid to those identified electrification areas. To determine electrification areas spatially, electoral areas (EAs) demarcated as rural during the run up to the 1994 elections were used to identify rural areas; and Ethekwini Metropolitan Municipality, current electrification projects, reserves and a buffer zone around existing transformers excluded. Household point data was used to polygonize the remaining area, and those polygons were aggregated on their calculated area to create future rural electrification areas (FREA). A points and weighting system; based on one initially used in Namibia and further developed in an electrification planning model by RAPS Consulting, CSIR and DME to prioritise villages for electrification; was applied to calculate point scores for each FREA and other criteria such as distance from a network with capacity considered to determine a prioritised list of FREA that can be electrified immediately. Roads, land cover, household positions and slope were used to design the shortest path from the grid to the three highest scoring FREA. Each layer was reclassified, ratings applied and the layers combined to successfully determine the final path in terms of the criteria used. Interest in using GIS for spatial planning has led to a GIS Initiative Group (GISIG) being formed at Eskom Distribution in Eastern Region to address data collection, co-ordination of planning, tools written previously but never implemented being re-evaluated and, more recently, new tools being designed. However, much is still needed in terms of research, resolving of data quality issues, testing of points and weighting systems, and for functionally independent sections to work together on making changes to age-old system structures and processes before any of the recommendations resulting from this study can be effectively implemented. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
106

Avaliação do programa "luz para todos", implantado na cooperativa de eletrificação rural de Itaí, Paranapanema e Avaré - Ceripa /

Higuchi, Cristiane Aparecida Pelegrin, 1977. January 2008 (has links)
Orientador: Odivaldo José Seraphim / Banca: Elias José Simon / Banca: José Francisco Rodrigues / Resumo: A eletrificação rural constitui elemento de fundamental importância para o aumento da produção e aprimoramento do produto agrícola que conseqüentemente resulta num melhor nível de vida para o agricultor. Com novas e modernas tecnologias à disposição, o produtor rural tem a propriedade valorizada e pode buscar alternativas agrícolas para aumentar sua renda liquida e gerar empregos, além de estimular o mercado de produtos industrializados. O objetivo deste trabalho é avaliar a evolução do Programa de Eletrificação Rural "Luz para Todos", e apresentar os principais aspectos técnicos e sociais do programa, como veículo no desenvolvimento, referente aos pequenos produtores rurais na área de atuação da cooperativa de Eletrificação Rural de Itaí, Paranapanema e Avaré (CERIPA). Para tanto, foram analisados dados técnicos, financeiros e sociais, através de cadastros e planilhas, com o devido acompanhamento da implantação do Programa. Através destes dados, foi possível determinar índices técnicos e econômicos referentes à implantação do Programa e verificar a evolução do número de consumidores, a potência instalada, a energia faturada e receita bruta da cooperativa. Para a cooperativa, a implantação do programa promoveu um vetor de desenvolvimento, pois todos os consumidores atendidos, englobaram na massa de consumidores da cooperativa, tornando-a mais sólida e mais competitiva no mercado energético. Em apenas sete anos, no período de 2000 a 2006, a cooperativa teve um aumento de mais de 50% no número de ligações, dado este que se refletiu na carga instalada, triplicando o faturamento bruto. Pode-se notar no desenvolvimento deste trabalho uma forte omissão do governo com relação às metas estabelecidas e não cumpridas, onde se aplica simplesmente uma multa simbólica sobre o investimento não utilizado no programa. Não são levantados problemas...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Rural electrification is an outstanding element for production increase and agricultural product improvement which, consequently, results in better life quality for the small farmer. With new and modern technologies available, the rural producer has his property valorized and is able to search for agricultural alternatives to rise his net income and generate employment, besides stimulating the industrialized products market. This work aims to evaluate the evolution of the "Electric Lighting for All" Program and present main technical and social aspects of the program, as a vehicle of development, referring to the rural small farmers at CERIPA Rural Electrification Cooperative of Itaí, Paranapanema and Avaré. It was analyzed technical, financial and social data through registers and sheets with the proper following of the Program implantation. From the data, it was possible to determine the technical and economic indexes related to the Program settlement and verify the increase in number of consumers, installed power, the invoiced electrical energy and gross income of the Cooperative. For the Cooperative, this Program settlement promoted a vector of development, since all the attended small farmers entered the cooperative, making it more solid and competitive in the market. From 2000 to 2006, the cooperative enhanced over 50% reflecting in the installed power, triplicating the gross income.It can be noticed in this work development high omission of the government concerning the established targets not accomplished, where a symbolic tip is simply applied over the investment not used in the program. Problems are not raised, targets are not questioned; the allowance is distributed only to justify a "political willing" with the citizen. / Mestre
107

Investigating the socio economic impact of electrification in Mnquma Municipality

Jobela, Sonwabo January 2011 (has links)
The aim of this research was to investigate the socio economic impact of electrification in Mnquma Municipality in the province of Eastern Cape. Mnquma Municipality has a backlog of about 25475 households that have not yet been electrified. There is a high demand of electricity in villages that have not yet been electrified. Eskom Southern Region has about 5 Million electrified households. The year 2012 was declared as year of universal access of electricity in South Africa. In the last three years amount of electrified households has been coming down at alarming rate. It is against this background that the study sought to investigate the socio economic impact of electrification of households. This study is a comparative study where two villages are compared. One village is electrified whilst the other village is not electrified. The study is based on the questionnaire opinion survey where respondents‟ views and opinion are solicited to test if electricity improves the socio economic conditions of Mnquma households. The study confirmed the findings of the research if electrification has improved the socio economic condition and if electricity is a preferred source of energy. The study proposed recommendations encompasses strategic responses to check if Government is achieving the desired goal through electrification of households.
108

Approches technico-économiques d’optimisation des systèmes énergétiques décentralisés / cas des systèmes hybrides PV/Diesel

Tsuanyo, David 17 June 2015 (has links)
Le développement des systèmes énergétiques renouvelables et/ou conventionnels pour l’alimentation des zones décentralisées est confronté à de multiples barrières techniques, institutionnelles, socioculturelles et surtout financières. La solution défendue dans cette thèse est de rechercher des approches pour concevoir des systèmes durables et rentables, conditions requises pour le développement de l’électrification rurale par le secteur privé. L’analyse des différents critères économiques permet tout d’abord de définir plusieurs types d’équivalence entre critères économiques : équivalence décisionnelle, équivalence pour le dimensionnement optimal et équivalence pour le classement des solutions techniques. Cette première étude permet de démontrer que les 3 critères économiques habituellement utilisés (le LCOE, le taux de rentabilité interne, et le temps de retour sur investissement) aboutiront à des solutions techniques optimales différentes. Un modèle technico-économique est alors développé pour les systèmes hybrides PV/Diesel sans batteries de stockage en site isolé. Une application au site 2iE-K1 (Ouagadougou) permet de valider la conformité des modèles par comparaison au logiciel HOMER. On montre que les critères de taux de rentabilité interne maximum ou de temps de retour sur investissement minimum limitent l’investissement et le montant de la dette maximale. Plusieurs solutions optimales, dépendant du critère économique considéré, sont alors proposées pour un cas d’application réel : l’électrification de la localité rurale de Bilgo. Le travail réalisé au cours de cette thèse se situe donc dans la branche des outils de dimensionnement optimal et d’optimisation technico-économique des systèmes de production décentralisée d’énergie. / The development of renewable and / or conventional energy systems for power supply to decentralized areas faces many technical, institutional, socio-cultural and financial barriers. The solution recommended in this thesis is to look for approaches to design sustainable and cost-effective systems for the development of rural electrification by the private sector. An analysis of various economic criteria allows first to define several types of equivalence inter-linking them: equivalence for investment decision, equivalence for the optimal sizing and equivalence for ranking technical solutions. This first study shows that the three economic criteria usually used (levelized cost of energy, internal rate of return and discounted payback period) lead to different optimal technical solutions. A techno-economic model is then developed for off-grid batteryless PV/Diesel hybrid systems. An application to 2iE-K1 campus (Ouagadougou) has been done to validate the compliance of models compared to HOMER software. It shows that the maximum internal rate of return criteria or minimum discounted payback period criteria reduces the initial investment and the amount of the maximum debt. Several optimal solutions are then obtained, depending on economic criteria under consideration. The electrification of the rural community of Bilgo has been chosen for a real case study. The work carried out, through this thesis, could be classified in the category of optimal design and techno-economic optimization tools for off-grid energy production systems.
109

Le rôle de l'électricité sur le bien-être de la population rurale. Cas de Madagascar / The role of electricity on rural population's well-being. Case of Madagascar

Randriantseheno, Tsilavina maholiarisoa 23 September 2016 (has links)
A Madagascar, la politique d’électrification rurale repose sur le partenariat entre les acteurs public et privé. Le modèle d’électrification y est essentiellement basé sur des systèmes décentralisés. De nos jours, ce secteur n’a pas encore prouvé sa pleine réussite. Le taux d’accès à l’électricité en zone rurale malgache demeure très faible. La plupart des recherches concernant l’efficacité des projets d’électrification porte sur les performances techniques et financières des systèmes de production. Très peu d’études s’intéressent aux questions relatives à l’impact socio-économique. La thèse vise à apporter une meilleure connaissance des mécanismes par lesquels l’électrification rurale joue sur le bien-être humain, dans le cadre d’une évaluation d’impact. L’analyse est abordée du point de vue de l’approche par les capabilités. L’exigence de ce cadre en termes de mesure des réalisations, et des réalisables qui ne sont pas supposés observables directement, demande une démarche méthodologique plus rigoureuse. Aussi, la thèse propose une combinaison d’approches différentes, qualitatives, quantitatives ainsi que de dynamique temporelle sur la base d’événements décrits par des enquêtes biographiques. La thèse met en évidence l’intérêt de resituer l’électrification rurale sur une trajectoire de vie autrement qu’un simple événement ponctuel. Les résultats révèlent que la hausse des capabilités constitue une condition nécessaire pour accéder à l’électricité. Cette source d’énergie renforce les capabilités des ménages ruraux en s’insérant dans une trajectoire de vie préétablie. Dans une moindre mesure, l’électrification rurale permet aux ménages pauvres d’initier une trajectoire ascendante. / In Madagascar, rural electrification policy is focused on the partnership between public and private actors. Decentralized system is mainly the model used to serve rural electricity needs. However, this sector hasn’t shown its full success. The rate of access to electricity remains very low in Malagasy rural area. Most research on the effectiveness of electrification projects concerns the technical and financial performances of production systems. Studies related to socio-economic impact are very few. The thesis aims to provide a better understanding on the mechanisms by which rural electrification influences human well-being, through an impact assessment. Evaluation is based on Sen’s capabilities framework. The empirical applications of this framework should provide more rigorous methodological approach. Therefore, a combination of different approaches, qualitative, quantitative and temporal dynamics is proposed. The thesis highlights the interest to place rural electrification on a life trajectory other than a one-time event. Results reveal that, the rise of capabilities is a condition for access to electricity. This energy enhances households’ capabilities by inserting in a predetermined trajectory. Findings demonstrate, to a lesser extent, that rural electrification allows poor households to initiate an upward trajectory.
110

The History of the Brazos Electric Power Co-operative

Mitchell, Merlin Merton 01 1900 (has links)
A history of the establishment of the Rural Electrification Administration and the Brazos Electric Power Cooperative.

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