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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

Termisk Vattenpump / Thermal waterpump

Klingberg, Hans, Stendal, Marcus January 2009 (has links)
<p> </p><p>This degree project aims at developing a concept for how to use solar energy to pump up water. The target audience is people living in areas where the functioning of the electricity and water network is absent. In these areas, the hand-powered water pump is the most common technology. The degree project's goal is to find an economically viable alternative to the time consuming hand-powered water pumps. The power comes from solar energy. Studies have shown that 90% of the hand pumps that have been installed have broken down within the first three years. This is because of an incorrect basic design that severely shortens lifetime.</p><p>How would a simple and robust design look like? An information seeking phase about the conditions and techniques that exist in these areas, were the basis for the requirements of the concept. Because of this the authors chose a concept similar to a simple steam engine. The pump uses vaporized water, by means of concentrating sunlight to pump up water. In total, 33 different concepts were created. The concepts were filtered in three stages that resulted in a final concept. The final concept contains a reflective dish that concentrates the sunlight to a receiver where the water evaporates. The built up pressure forces up water towards the surface from a tank located below the groundwater. The system is designed to supply 25 families with 2.5 cubic meters of water a day. The pump is working during the daily 8 hours of sunshine. The system will have an expected low efficiency <5.3% which is the theoretical maximum efficiency. Further development of the system requires a detailed analysis of the situation on the ground. Tests should be performed to examine how well the technology works and how sensitive the system is to disturbances.</p><p> </p>
2

Termisk Vattenpump / Thermal waterpump

Klingberg, Hans, Stendal, Marcus January 2009 (has links)
This degree project aims at developing a concept for how to use solar energy to pump up water. The target audience is people living in areas where the functioning of the electricity and water network is absent. In these areas, the hand-powered water pump is the most common technology. The degree project's goal is to find an economically viable alternative to the time consuming hand-powered water pumps. The power comes from solar energy. Studies have shown that 90% of the hand pumps that have been installed have broken down within the first three years. This is because of an incorrect basic design that severely shortens lifetime. How would a simple and robust design look like? An information seeking phase about the conditions and techniques that exist in these areas, were the basis for the requirements of the concept. Because of this the authors chose a concept similar to a simple steam engine. The pump uses vaporized water, by means of concentrating sunlight to pump up water. In total, 33 different concepts were created. The concepts were filtered in three stages that resulted in a final concept. The final concept contains a reflective dish that concentrates the sunlight to a receiver where the water evaporates. The built up pressure forces up water towards the surface from a tank located below the groundwater. The system is designed to supply 25 families with 2.5 cubic meters of water a day. The pump is working during the daily 8 hours of sunshine. The system will have an expected low efficiency &lt;5.3% which is the theoretical maximum efficiency. Further development of the system requires a detailed analysis of the situation on the ground. Tests should be performed to examine how well the technology works and how sensitive the system is to disturbances.
3

Demanda e capacidade resolutiva do setor de retina e vitreo de um hospital terciario / Problem solving capacity and demand for vitreoretinal diseases in university health center

Soares, Paulo Henrique Limeira 26 September 2007 (has links)
Orientadores: Newton Kara-Jose, Rodrigo Pessoa Cavalcanti Lira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-09T11:04:58Z (GMT). No. of bitstreams: 1 Soares_PauloHenriqueLimeira_D.pdf: 4979795 bytes, checksum: a3e56d06c84ca0781142bae68e8cc1ef (MD5) Previous issue date: 2007 / Resumo: Os objetivos deste estudo foram caracterizar a demanda e a capacidade resolutiva de um serviço oftalmológico terciário para pacientes com doenças vitreorretinianas em uma população urbana definida no sudeste brasileiro. Os dados foram coletados dos pacientes consecutivos atendidos pela primeira vez no Departamento de Oftalmologia, Universidade Estadual de Campinas, São Paulo, Brasil, de 1º. de junho de 2003 a 31 de julho de 2004. A capacidade resolutiva e a incidência da demanda foram calculadas para cirurgia de retina e fotocoagulação. Os dados foram analisados com os programas EpiInfo¿ 2000 (Centers for Disease Control and Prevention, Atlanta, Georgia, USA) e Statistical Package for the Social Sciences® (version 11.0). A estimativa populacional da área de abrangência é de 3.389.294 de pessoas. Dos 7500 pacientes referidos para o Departamento no período do estudo, 641 foram incluídos no estudo. Os diagnósticos considerados para análise foram descolamento de retina (26,0%), retinopatia diabética (21,0%) e hemorragia vítrea (7,7%) com medianas das idades de 52, 59 e 57,5, respectivamente. A capacidade resolutiva para descolamento de retina, hemorragia vítrea e retinopatia diabética foram, respectivamente, 38,1%, 33,0% e 93,5%. O principal motivo para a não realização de cirurgia de retina ou fotocoagulação foi horário não disponível (87,1%). A incidência da demanda global para descolamento de retina foi 9,2:100.000. Descolamentos em fácicos não traumáticos apresentaram a mais alta incidência da demanda com 7,1:100.000. 26,5% dos pacientes apresentaram descolamentos de retina inoperáveis. A incidência da demanda idade-específica aumenta com a idade. Descolamentos de retina não traumáticos em fácicos foram o tipo mais comum. A incidência de descolamentos traumáticos foi maior no gênero masculino. O estudo revelou que condições que ameaçam a visão como descolamento de retina e retinopatia diabética não são totalmente cobertos pelo Serviço nesta área. Alternativas para solução do problema são consideradas. O estudo fornece informações para planejamento de serviços oftalmológicos de alta complexidade na população estudada / Abstract: The aims of the study were to evaluate either the characteristics of the demand and the performance of the tertiary care delivered to patients with vitreoretinal diseases in a defined urban population in the Southeast of Brazil. Data were collected from consecutive first time patients between June 1 2003 and July 31 2004 in the Department of Ophthalmology, State University of Campinas, São Paulo, Brazil. Problem-solving capacity rates as well as demand incidence were calculated for vitreoretinal surgery and photocoagulation. Data were entered into the Statistical Package for the Social Sciences (version 11.0). There were a total population of 3 389 294 in the cities of Campinas catchment area. Of the 7500 patients referred to the Department, 641 were deemed to analysis. Diagnoses analyzed were retinal detachment (26.0%), diabetic retinopathy (21.0%), and vitreous hemorrhage (7.7%). Median ages were 52, 59, 57.5, respectively. The problem-solving capacity rates showed that 38.1%, 33.0%, and 93.5% of those eligible for ophthalmic intervention (retinal detachment, vitreous hemorrhage and diabetic retinopathy) have obtained the treatment. The main reason for not performing the treatment was lack of available intervention time (87.1%). The overall demand incidence of retinal detachment was 9.2:100 000. Nontraumatic phakic detachments had the highest demand incidence of 7.1:100 000. 26,5% of all patients seeking treatment presented inoperable cases of retinal detachments. The age specific demand incidence increases with age. Nontraumatic phakic detachments were the most common type of detachment. The incidence of the traumatic types of detachment was higher in males than that in females. Sight threatening conditions are not thoroughly covered by the health system in this area. Some alternatives to reduce the problem are considered. It provides valuable information on planning high complexity eye services in the population likely to be served. / Doutorado / Oftalmologia / Doutor em Ciências Médicas

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