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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.
41

Combining interventions: improved chimney stoves, kitchen sinks and solar disinfection of drinking water and kitchen clothes to improve home hygiene in rural Peru.

Hartinger, Stella M., Lanata, Claudio F., Gil, Ana I., Hattendorf, Jan, Verastegui, Hector, Mäusezahl, Daniel 25 March 2014 (has links)
Home based interventions are advocated in rural areas against a variety of diseases. The combination of different interventions might have synergistic effects in terms of health improvement and cost effectiveness. However, it is crucial to ensure cultural acceptance. The aim of the study was to develop an effective and culturally accepted home-based intervention package to reduce diarrhoea and lower respiratory illnesses in children. In two rural Peruvian communities we evaluated the performance and acceptance of cooking devices, household water treatments (HWT) and home–hygiene interventions, with qualitative and quantitative methods. New ventilated stove designs reduced wood consumption by 16%. The majority of participants selected solar water disinfection as HWT in a blind tasting. In-depth interviews on hygiene improvement further revealed a high demand for kitchen sinks. After one year of installation the improved chimney stoves and kitchen sinks were all in use. The intervention package was successfully adapted to local customs, kitchen-, home–and hygiene management. High user satisfaction was primarily driven by convenience gains due to the technical improvements and only secondarily by perceived health benefits. / Revisión por pares.
42

Análise da relação entre o faturamento do consumo de energia elétrica e demanda de potência ativa e reativa utilizando hiperbolóides de carga e potência

Guelfi, Rangel [UNESP] 31 May 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-05-31Bitstream added on 2014-06-13T20:09:50Z : No. of bitstreams: 1 guelfi_r_me_ilha.pdf: 667745 bytes, checksum: 4cf02e10ba92af5e81fd3f18fda6f6cd (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / No presente trabalho é apresentado um método para o cálculo de volumes determinados por K-Hiperbolóides de Carga e Potência, de modo a reduzir os gastos de empresas consideradas, em relação ao fator de potência. A redução de gastos é obtida alterando-se o valor máximo do fator potência que se pretende chegar, do fator de potência ideal 1, para o fator de potência de referência 0,92, ou mantendo-o quando já estiver acima de 0,92. Quando o fator de potência é maior ou igual a 0,92 ele já está eficiente, assim, não há necessidade de se chegar ao fator de potência ideal. É realizada uma comparação entre um método existente na literatura e o método proposto no presente trabalho, para determinar os pontos em que estes métodos diferem no cálculo dos volumes determinados pelos K-Hiperbolóides de Carga e Potência e mostrar a eficácia do método proposto. Estes métodos são equiparados, com relação a redução obtida no faturamento da conta de energia elétrica. A redução no faturamento da conta de energia elétrica que deve ser pago à concessionária é obtida por meio da diminuição da demanda contratada pela empresa; por sua vez a diminuição desta demanda é alcançada através da fórmula do fator de carga. Considerando-se a demanda média e o maior fator de carga obtido no período em estudo, encontra-se assim, uma nova demanda máxima menor que a demanda atual utilizada pela empresa. Logo, esta demanda máxima passa a ser a demanda que será contratada pela empresa, assim, esta nova demanda resulta em uma nova fatura que deve ser paga a concessionária de energia elétrica, menor que a fatura atual. / The present work presents a method for the calculation of volumes determined for K- Load and Power Hyperboloid, in order to reduce the expenses of considered companies, in relation to the power factor. The reduction of expenses is gotten by changing the maximum value of the wished power factor, of the ideal power factor1, to the reference power factor 0,92,or keeping it when it s above 0,92. When the power factor is higher or equal 0,92, it s already efficient, thus, it is not necessary to achieve the ideal power factor. A comparison is carried between an existing method in the literature and the considered method in the present work, to determine the points where these methods differ from each other in the calculation of the volumes determined for the K-Load and Power Hyperboloid and to show the effectiveness of the considered method. These methods are equalized, regarding the reduction gotten in the invoicing of the electric energy account. The reduction in the invoicing of the account of electric energy that must be paid to the concessionaire is gotten through the reduction of the contracted demand by the company; in turn the reduction of this demand is reached through the formula of the load factor. Considering the average demand and the highest load factor gotten in the period in study, this way a new demand, lower than the current demand used by the company, is gotten. Therefore, this maximum demand starts to be the demand that will be contracted by the company, thus, this new demand results in a new invoice which must be paid to the concessionaire of electric energy, lower than the current invoice.
43

Estudo das propriedades químicas dos rejeitos de dragagemas para utilização como solo fabricado para fins agrícolas

Teixeira, Laurita dos Santos January 2009 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia Oceânica, Escola de Engenharia, 2009. / Submitted by Lilian M. Silva (lilianmadeirasilva@hotmail.com) on 2013-04-20T19:57:52Z No. of bitstreams: 1 Estudo das propriedades químicas dos rejeitos de dragagem para utilização como solo fabricado para fins agrícolas.pdf: 3400808 bytes, checksum: ee6262b434d2d3a9593672ab06f9c86b (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-06-04T19:12:49Z (GMT) No. of bitstreams: 1 Estudo das propriedades químicas dos rejeitos de dragagem para utilização como solo fabricado para fins agrícolas.pdf: 3400808 bytes, checksum: ee6262b434d2d3a9593672ab06f9c86b (MD5) / Made available in DSpace on 2013-06-04T19:12:49Z (GMT). No. of bitstreams: 1 Estudo das propriedades químicas dos rejeitos de dragagem para utilização como solo fabricado para fins agrícolas.pdf: 3400808 bytes, checksum: ee6262b434d2d3a9593672ab06f9c86b (MD5) Previous issue date: 2009 / A dragagem pode ser considerada como o ato de retirada de material do leito dos corpos de água, principalmente para o aprofundamento e alargamento de canais em rios, portos e baías,construção de diques, fundações para pontes e outras estruturas. Devido à necessidade de navegação de grandes embarcações no Porto do Rio Grande, periodicamente é necessária a realização de dragagens. A pesquisa com material dragado é feita devido ao potencial econômico do rejeito gerado e ao problema ambiental gerado por ele. É importante desde o projeto da obra, o conhecimento das características físico-químicas dos sedimentos. A natureza de contaminantes em materiais dragados varia muito, dificultando as considerações sobre usos benéficos do rejeito, e embora algumas vias navegáveis estejam localizadas próximas a áreas industrializadas ou centros urbanos, a maior parte do material dragado é considerada não contaminada. A caracterização do material dragado para uso como fertilizante é feita pela determinação de matéria orgânica, pH, salinidade, N, P, K, Ca, Mg,metais pesados e Capacidade de Troca Catiônica (CTC), que depende do pH e diretamente proporcional a concentração de argila, conteúdo de matéria orgânica e sua granulometria.Foram feitas análises químicas para a determinação de contaminantes na lama (segundo o CONAMA), e análise de fertilidade do solo (Comissão de Química e Fertilidade do Solo RS/SC) para o estudo da sua utilização. Assim, o estudo do resíduo do material dragado é de suma importância tanto para os custos da operação, quanto para o aproveitamento desse material e cuidado com o meio ambiente. O resíduo estudado foi depositado em bacias de sedimentação em 2001, onde em 2006 mostrou um grande desenvolvimento de vegetação na área que a lama foi depositada, indicando o potencial do resíduo, que foi comprovado pelas análises. / Dredging may be considered as the act of removal of material from the bed of the water bodies, mainly to the deepening and widening of channels in rivers, harbors and bays, construction of dams, foundations for bridges and other structures. Due to the need for navigation of large vessels in the Port of Rio Grande, it is periodically necessary to carry out dredging. The research with dredged material is carried out due to the economic potential of the waste generated and the environmental problem created by it. It is important since the project, the knowledge of the physicochemical characteristics of sediments. The nature of contaminants in dredged material varies widely, making it difficult the comments on the beneficial uses of waste, and although some waterways are located close to industrial areas or urban centers, most of the dredged material is not considered contaminated. The characterization of dredged material for use as fertilizer is made by the determination of organic matter, pH, salinity, N, P, K, Ca, Mg, heavy metals and cation exchange capacity (CEC), which depends on the pH and is directly proportional to concentration of clay, content of organic matter and its granular size. Chemical analyses were performed for the determination of chemical contaminants in the mud (according to CONAMA), and analysis of soil fertility (Commission of Chemistry and Soil Fertility RS / SC) for the study of its use. Thus, the study of the residue of the dredged material is of great importance for the costs of operation, for the use of this material and for care with environment. The waste studied was deposited in basins of sedimentation in 2001. In 2006 this area showed a great development of vegetation where that the mud was deposited, indicating the potential of the residue, which was proven by analyses.
44

Development of an algorithm for estimating Lead-Acid Battery State of Charge and State of Health / Utveckling av en algoritm för beräkning av blybatteri laddningstillstånd och hälsotillstånd

Samolyk, Mateusz, Sobczak, Jakub January 2013 (has links)
In this paper, a state of charge (SOC) and a state of health (SOH) estimation method for lead-acid batteries are presented. In the algorithm the measurements of battery’s terminal voltage, current and temperature are used in the process of SOC calculation. The thesis was written in cooperation with Micropower AB. The algorithm was designed to fulfill the specific requirements of the electric vehicles application: an error below 5% of SOC, computational simplicity and the possibility of being implemented in a basic programming languages. The current used method at Micropower, Coulomb counting, is compared with a method presented by Chiasson and Vairamohan 2005 based on modified Thevein circuit during charging and discharging of the battery. The Thevenin based method gave better result compared to Coulomb counting but seems not to fulfill Micropowers requirements. A correction method based on periods of no charging or discharging, possible to be used together with Coulomb counting as well as with the Thevenin method was developed. The evaluation method indicates that when using also the correction method the Micropowers requirements are fulfilled. / I detta papper, är ett laddningstillstånd (SOC) och hälsotillstånd (SOH) skattningsmetod för blybatterier presenteras. I algoritmen mätningarna av batteriets polspänning, ström och temperatur används i processen för SOC beräkning. Avhandlingen är skriven i samarbete med Micropower AB. Algoritmen har utformats för att uppfylla de särskilda kraven för elektriska fordon: ett fel under 5% av SOC, computational enkelhet och möjligheten att genomföras i ett grundläggande programmeringsspråk. Den nuvarande metoden vid Micropower, Coulomb räkning, jämförs med en metod som presenteras av Chiasson och Vairamohan 2005 baserad på modifierad Thevein kretsen under laddning och urladdning av batteriet.
45

Vem för de törstigas talan? : En studie av debatten kring vattensektorn

Stenholm, Moa January 2008 (has links)
1.1 billion people are today living without sustainable access to improved water. The debate over the water sector has been dominated by the discussion over whether public or private actors are the most competent to manage it. In this paper the arguments pro and contra the two positions are presented to try to overview the debate and to try to find new ways to approach the question of the people living without clean water. By examining possible alternatives towards the discussion of public and private actors, it might result in some new approaches on how to move closer towards a solution. One alternative is local, small- scale projects which focus on the situation of the targetgroup in most need. I have in this paper tried to find signs of that the debate is changing in a way that would bring positive outcomes for the people living without access to improved water. The debate is changing, both the private as well as the public sector is changing their ways of working and the alternative approach is increasing its influence. Hopefully the debate can move away from the discussion of ideology and acknowledge the strengths of each other to result in possible solutions of the water problems. With the increasing interest and concern for the question of water there is thus an opportunity for a change in the debate that would benefit the ones living without sustainable access to improved water.
46

Electrical power energy optimization at hydrocarbon industrial plant using intelligent algorithms

Al-Hajri, Muhammad T. January 2016 (has links)
In this work, the potential of intelligent algorithms for optimizing the real power loss and enhancing the grid connection power factor in a real hydrocarbon facility electrical system is assessed. Namely, genetic algorithm (GA), improve strength Pareto evolutionary algorithm (SPEA2) and differential evolutionary algorithm (DEA) are developed and implemented. The economic impact associated with these objectives optimization is highlighted. The optimization of the subject objectives is addressed as single and multi-objective constrained nonlinear problems. Different generation modes and system injected reactive power cases are evaluated. The studied electrical system constraints and parameters are all real values. The uniqueness of this thesis is that none of the previous literature studies addressed the technical and economic impacts of optimizing the aforementioned objectives for real hydrocarbon facility electrical system. All the economic analyses in this thesis are performed based on real subsidized cost of energy for the kingdom of Saudi Arabia. The obtained results demonstrate the high potential of optimizing the studied system objectives and enhancing the economics of the utilized generation fuel via the application of intelligent algorithms.
47

Determinants of consumer willingness to pay for organic food in South Africa

Engel, Wendy Elaine 24 November 2008 (has links)
The growing South African domestic organic food industry is a new feature of the recent structural shifts in food demand in the country. Consumer demand preferences for organic food impact on agricultural production methods due to the unintended positive consequences of improved soil fertilisation, increased productivity and increased use of indigenous knowledge. Understanding consumer demand for food, specifically organic food, in South Africa is becoming increasingly important as consumers’ attitudes and preferences strongly influence the direction of food retailers’ strategies. This study used a single bound dichotomous choice contingent valuation method (CVM) to analyse the determinants of organic food in SA, specifically organic fruit juice and wine. Data was collected from a CVM questionnaire administered to 550 respondents in a food retail store over 3 days. Findings from this study indicate consumers believe organic food is more nutritious and tastier than conventional food, organic agriculture benefits both small-scale and local farmers and that consumers require a guarantee of the organic origin of organic products. Emphasising these benefits and directly referring to the small-scale and local farmers from whom organic products have been procured in advertisement campaigns may improve retail marketing strategies for organic food. It also highlights that South African policy makers urgently have to finalise the promulgation of the draft legislation on organic standards to provide certainty to local consumers and hence a positive signal to current and prospective investors in the local organic industry. Empirical results from this study show that socio-demographic factors do influence consumer demand and supports the need for disaggregated food demand analysis in South Africa. Socio-demographic factors do influence South African consumers’ decision to purchase organic food and younger age increases the probability of the decision to purchase organic food; whereas being married and being in possession of non-formal training qualifications decreases this probability. Organic consumer awareness and education programmes should therefore be targeted at older, unmarried consumers with high levels of formal education. The domestic market may provide a niche for South African wine producers as this study showed that the majority of respondents interviewed are prepared to pay higher premiums for organic wine. A limitation of this study is that these results may reflect consumers’ demand for wine as a luxury good as no separate analysis and questions were included on consumer demand for wine. Policy makers should support small-scale producers and black vintners in the Western Cape to exploit growing organic wine industry by conducting further research for a organic wine marketing campaign that brands organic wine highlighting procurement from small-scale producers, local farmers and positive contribution to environment, providing extension services to small-scale producers on organic wine production, investing in research and development in organic wine production facilitating mentorship between small-scale farmers and existing organic wine producers and lobbying national department of agriculture to finalise the draft South African organic standard given that South African consumers require guarantee of organic origin. Agents in the private sector may exploit opportunities in the organic wine industry by targeting consumers that are younger and old age of Christian faith, lobby the South African government to finalise the draft organic standard, highlight attitudes that organic wine contribute positively to the environment, local and small-scale farmers in organic wine marketing campaigns and procure more organic wine from small-scale and local organic wine producers. Local and small-scale fruit producers and fruit processors in the Western Cape are well positioned to exploit growth forecasted in the domestic organic fruit juice sector given its global reputation for producing high quality fruit, proven manufacturing capabilities and expertise in fruit juice production. Both younger and older age positively influences willingness to pay for organic fruit juice but younger consumers are willing to pay higher prices than older consumers for organic fruit juice. Consumers that are the head of households, by being in the position of food purchaser, are also willing to pay higher prices for organic fruit juice. Afrikaans speaking consumers, 77 percent belonging to the coloured population group of which 69 percent earn less than an average monthly income of R3500 are less likely to pay higher prices for organic fruit juice due to lower disposal incomes. South African citizens that represent almost 90 percent of the Western Cape population are concerned about environmental issues confirmed by beliefs that organic food contributes to the environment, small-scale and local farmers. This concern is expressed in the higher prices that South African citizens are willing to pay for organic fruit juice. These empirical findings indicate the target consumers that organic fruit juice marketing campaigns should focus on. Specific policy interventions to promote the industry include public investment in research and development in organic production methods, extension service provision on organic production methods to small-scale farmers and development of mentorship programmes between existing small-scale and existing organic producers. Copyright / Dissertation (MInstAgrar)--University of Pretoria, 2009. / Agricultural Economics, Extension and Rural Development / unrestricted
48

Sustainability Analysis of Domestic Rainwater Harvesting Systems for Current and Future Water Security in Rural Mexico

Neibaur, Elena E 24 June 2015 (has links)
Rainwater harvesting, the act of capturing and storing rain, is an ancient practice that is increasingly utilized today by communities to address water supply needs. This thesis examines whether domestic rainwater harvesting systems (DRWHS) can be a sustainable solution as defined by social, water quality, and technical feasibility for water security in semi-arid, rural environments. For this study, 50 surveys and 17 stored rainwater analyses were conducted in San Jose Xacxamayo, Mexico, in conjunction with my Peace Corps work of implementing 82 DRWHS. Results showed that all DRWHS were socially feasible because of cultural acceptance and local capacity. Water quality analyses showed that four DRWHS contained coliform bacteria; deeming water unfit for human consumption. Technical feasibility, examined through climate analyses, showed an average year-round reliability of 20-30% under current and future rainfall regime. The DRWHS can be a sustainable water supply option with roof expansion and treatment prior to consumption.
49

Application of Spatial and Descriptive Analysis Methods to Determine Relationship Between Hardware Subsidies and the Sanitation Marketplace

Devuyst, Danielle 25 March 2016 (has links)
Sanitation marketing is an emerging approach of strengthening the local private sector to implement scalable and sustainable improved sanitation coverage in developing countries, specifically among the poor. It encourages the enhancement of sanitation market supply and demand by developing distribution infrastructure and stimulating consumer interest. Unlike interventions that provide hardware subsidies to initiate sanitation demand, financial support for sanitation marketing is used exclusively for the research and development of the market; this encourages the private sector to become independent and self-sufficient. Qualitative data suggests that while sanitation marketing projects have been successful at implementing replicable and sustainable sanitation coverage, they are not effective in close proximity to other programs that provide hardware subsidies. The aim of this study is to determine how hardware subsidies impacted iDE’s (formerly International Development Enterprise) Cambodia Sanitation Marketing Scale-Up (SMSU) project using quantitative data collected between 2010 and 2014, and to develop an approach that best illustrates this relationship. Using their project database of 48,844 transactions in 9 provinces, QGIS 2.8.1 and MS Excel were used to determine the correlations between the NGO (subsidized) and customer sales. QGIS maps and time-lapse animations were effective in spatially juxtaposing the quantity and location of both NGO and customer sales, and MS Excel charts quantified the relationship as a function of time, identifying opposing correlational patterns. Within the Cambodia SMSU project, the provision of hardware subsidies (represented by NGO sales) resulted in the attrition of the sanitation marketplace (represented by customer sales) when the NGO sales landed between 71 and 889 in a single month, averaging 400 NGO sales in a month. Overall, 14 districts showed decreased customer sales in the presence of subsidies, and 36 districts showed increased customer sales in the presence of subsidies. Within this study, any district with over 395 sales in one month showed a decline in customer sales. There were 106 months within this project that the NGO and customer sales had a positive correlation and 110 months showing a negative correlation.
50

Transports et désenclavement dans la problématique du développement local à Téra au Niger / Transport and improved acces the issue of the local development Tera in Niger

Abdou Yonlihinza, Issa 05 December 2011 (has links)
Les difficultés dans la mobilité des personnes et des biens constituent l’un des obstacles majeurs à l’amélioration des conditions de vie des populations des pays sous-développés en général et celles de l’Afrique en particulier. Cette situation est particulièrement vraie pour la république du Niger. En observant la carte de l’Afrique on peut déjà imaginer les contraintes que peuvent induire la position géographique du pays pour ses échanges avec l’extérieur. Aussi, autant son isolement externe est criant, autant à l’intérieur du territoire national, l’enclavement est réel et pose un véritable problème de développement. L’étendue du territoire, son enclavement et une situation de fragilité économique constituent les éléments fondamentaux du contexte dans lequel évolue le secteur des transports au Niger. À l’échelle du territoire nigérien, le département de Téra permet d’appréhender les difficultés que pose le dysfonctionnement d’un système de transport et de voir comment la mobilité s’inscrit dans le processus du développement local. La faiblesse de l’offre des services de transport, la vétusté des infrastructures et le difficile accès aux moyens de transport sont des problèmes récurrents pour les populations. Les stratégies des acteurs n’ont eu qu’un impact limité sur l’amélioration de la mobilité dans l’espace départemental. Cet important dysfonctionnement dans la mobilité des personnes et des biens devra être résolu. / Difficulties in people’s mobility and in the flow of goods are one of the major obstacles to better the living conditions of populations in less-developed countries generally speaking, and particularly in Africa. That is true indeed for the Republic of Niger. As far as foreign trade is concerned, one can easily notice the constraints linked to the geographical location of the country, just by looking at the map of Africa. Not only its striking external isolation, but also its land-locked situation focuses a serious development issue. The size of this land-locked state and its economic weakness are the basic context for transportation in Niger. The department of Téra, which represents Niger well, allows understanding malfunctions in the transportation system and how mobility is part of the local development process. The low level of the services of transportation, the ageing infrastructures and the difficult access to means of transport are recurring problems for populations. The different stakeholders’ strategies have had limited impact on the improvement of mobility within the department. Those important malfunctions concerning people’s mobility and the flow of goods must be solved.

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