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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.
151

Food demand in rural China a study of rural household models /

Yan, Wenye. January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 134-138).
152

Pro-poor growth in Mozambique an exploration of its income and non-income dimensions /

Calder, Jason S. January 2005 (has links)
Thesis (M.A.)--Georgia State University, 2005. / Title from title screen. Sally Wallace, committee chair; L.F. Jameson Boex , James R. Alm, committee members. Electronic text (72 p.) : digital, PDF file. Description based on contents viewed June 26, 2007. Includes bibliographical references (p. 67-70).
153

Modelagem teórico-experimental de sistemas suspensos de secagem doméstica de vestuários /

Ribeiro, Jefferson Almeida. January 2002 (has links)
Orientador: Paulo Magalhães Filho / Banca: João Andrade de carvalho Júnior / Banca: José Nedilo carrinho de Castro / Banca: Pedro teixeira Lacava / Banca: Marco Aurélio Ferreira / Resumo: Com a evolução tecnológica e maior competitividade entre as empresas, aliadas as maiores exigências do mercado consumidor, tornou-se imprescindível, na avaliação e aceitação de secadoras, a necessidade de se fabricar equipamentos que operem com maior rendimento e menor consumo de energia. Tais fatos motivam a estudar e analisar o desempenho de sistemas suspensos de secagem de uso doméstico, com relação às características de funcionamento e eficiência no processo de desumidificação de tecidos, pois os parâmetros que influenciam o desempenho dos secadores e os mecanismos de secagem devem ser conhecidos nos graus de precisão requeridos para cada aplicação. Os parâmetros avaliados neste trabalho foram os seguintes: conteúdos de umidade do tecido na entrada e na saída do secador, condições de transferência de calor, temperatura, a velocidade, a direção e a umidade absoluta do fluxo do meio de fornecimento de calor, e a distribuição de temperatura superficial do tecido. As previsões teóricas são comparadas com os resultados experimentais obtidos em uma bancada de testes onde, conforme configurações apresentadas, simularam-se as condições reais de trabalho do sistema. Foram selecionados os tecidos mais utilizados para manufatura de vestuário: Jeans índigo, Flanela, Cotton-Lycra, Brim, Tergal, Viscose e Linho. / Abstract: Due to the technologic evolution and a higher competition among the companies, with the bigger requirements of the consuming market, it turned out necessary the manufacturing of equipment with higher performance and lower energy consumption. These aspects are motivation for studying and analyzing the performance of suspended household drying systems, regarding to their functioning features and efficiency on the cloth dehumidification process, since the parameters which influence the dryer performance and the drying mechanisms must be well known on the required accuracy degrees for each application. The parameters evaluated by this thesis were: cloth moisture contents at the dryer input and output; heat transfer conditions; speed, direction and absolute humidity of the heat supplying mean; and the cloth surface temperature distribution. The theoretical predictions are compared to the experimental results obtained from a test bench, where real system work conditions were simulated. The most utilized kinds of cloth for clothing manufacturing were selected, such as: blue-jeans, flannel, cotton-spandex, canvas, polyester, viscose rayon and linen. / Doutor
154

Fuel consumption of vehicles in urban areas, with particular reference to junction design

Gardiner, P. F. January 1984 (has links)
The purpose of this work was to examine vehicle fuel consumption in urban areas and provide a means by which consumption in various situations could be expressed. A review of previous work has been made, including details of the models used for overall consumption in urban areas. The models used are examined and compared with a simple model based on journey distance, journey time, and number of stops. The value of kinetic energy change as a predictive variable is also examined. An explanation of commercial vehicle consumption is provided, but there are difficulties in generalising this to include the whole vehicle fleet. Minimum estimates of consumption related to gross vehicle weight and functions of journey speed are therefore given for overall consumption and for urban conditions. The effect on fuel consumption of changing the area traffic signal control regime from TRANSYT to SCOOT is examined. The method used is to compare complete journeys of several kilometres rather than short lengths of road near each signal. Significant improvements are found for those routes which are mainly inside the control areas. Consumption at roundabouts, in queues, at simple curves and at part stops are considered in detail. The roundabout data and queueing data were collected on street, and the test track results for part stops and simple curves are compared with limited on street data. Predictive equations are given for the consumption of a 2. 2 litre car.
155

Modelagem teórico-experimental de sistemas suspensos de secagem doméstica de vestuários

Ribeiro, Jefferson Almeida [UNESP] January 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2002Bitstream added on 2014-06-13T20:46:45Z : No. of bitstreams: 1 ribeiro_ja_dr_guara.pdf: 976132 bytes, checksum: 3d4e175f5aca733de9311c6483ffc385 (MD5) / Com a evolução tecnológica e maior competitividade entre as empresas, aliadas as maiores exigências do mercado consumidor, tornou-se imprescindível, na avaliação e aceitação de secadoras, a necessidade de se fabricar equipamentos que operem com maior rendimento e menor consumo de energia. Tais fatos motivam a estudar e analisar o desempenho de sistemas suspensos de secagem de uso doméstico, com relação às características de funcionamento e eficiência no processo de desumidificação de tecidos, pois os parâmetros que influenciam o desempenho dos secadores e os mecanismos de secagem devem ser conhecidos nos graus de precisão requeridos para cada aplicação. Os parâmetros avaliados neste trabalho foram os seguintes: conteúdos de umidade do tecido na entrada e na saída do secador, condições de transferência de calor, temperatura, a velocidade, a direção e a umidade absoluta do fluxo do meio de fornecimento de calor, e a distribuição de temperatura superficial do tecido. As previsões teóricas são comparadas com os resultados experimentais obtidos em uma bancada de testes onde, conforme configurações apresentadas, simularam-se as condições reais de trabalho do sistema. Foram selecionados os tecidos mais utilizados para manufatura de vestuário: Jeans índigo, Flanela, Cotton-Lycra, Brim, Tergal, Viscose e Linho. / Due to the technologic evolution and a higher competition among the companies, with the bigger requirements of the consuming market, it turned out necessary the manufacturing of equipment with higher performance and lower energy consumption. These aspects are motivation for studying and analyzing the performance of suspended household drying systems, regarding to their functioning features and efficiency on the cloth dehumidification process, since the parameters which influence the dryer performance and the drying mechanisms must be well known on the required accuracy degrees for each application. The parameters evaluated by this thesis were: cloth moisture contents at the dryer input and output; heat transfer conditions; speed, direction and absolute humidity of the heat supplying mean; and the cloth surface temperature distribution. The theoretical predictions are compared to the experimental results obtained from a test bench, where real system work conditions were simulated. The most utilized kinds of cloth for clothing manufacturing were selected, such as: blue-jeans, flannel, cotton-spandex, canvas, polyester, viscose rayon and linen.
156

Factors affecting the energy consumption of data centres in South Africa

Young, Daleela 17 March 2010 (has links)
Companies in the US and the UK are frantically looking for ways to prevent future exorbitant data centre costs. South Africa does not have the space shortages, nor the high energy costs that companies in the US and UK experience. Hence, data centre energy efficiency is currently not a priority for South African businesses. However, things are about to change. Rising electricity costs and high growth rates in electricity consumption will motivate companies to consider implementing energy efficiency initiatives in their data centres. The purpose of the research begins at an assessment of the level of awareness of the energy consumption of data centres. This report looks at what the perceptions are of the factors that could cause fluctuations in energy usage at the data centre. The report further explores how South African companies are addressing potential fluctuations in usage, and what the motivation is for action taken. The methodology was a series of telephonic, semi-structured interviews with available and relevant stakeholders in data centre energy management. The interviewees were sourced from ICT companies in South Africa identified by the Market Research Foundation in the publication “Top ICT companies in South Africa 2005/6”, attendees of the ITWEB Green IT Summit 2008, and further referrals from these interviews. / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted
157

Wind tunnel investigation of road vehicle wakes

Davis, John P. January 1983 (has links)
No description available.
158

Status Consumption in High Tech Products Upgrading Purchase: A Study of the Extended Theory of Planned Behaviour Model.

Gu, Cheng January 2017 (has links)
The smartphones’ market is characterized by its fast evolving environment. In such an environment, the key concern for each company is how to continually encourage consumers to upgrade to the latest version before their existing model expires, which also highlights the importance of continual product enhancement. Consumers choose high-tech products not only for their functional values, but also for their symbolic values. This phenomenon is even more prevalent among products that tend to be conspicuously consumed. The high portability and multi-functional capabilities of smartphones make their use highly visible to users’ social surroundings, and consumers may choose to upgrade their existing smartphones for the perceived symbolic values provided by newer and enhanced models. The great success of the iPhone inspired the current research to further investigate the antecedents of upgrade intention and to uncover the symbolic value that smartphones provide to consumers. Reference group conformity is not the only way to fulfill symbolic values of selected products. Consumers also have the tendency to actively express their ideal self-image through acquiring and displaying material symbols and an ideal self-image sometimes also refers to a self-image with higher social status. Building upon the Theory of Planned Behavior (Ajzen, 1991), the proposed research model also explores the possible moderating effect of status consumption on the TPB model. A survey will be administered to university students (smartphone users) to collect primary data to measure the effectiveness of the new proposed research model. The results of this study provided a better understanding of consumers’ upgrading purchase intentions toward smartphones. Additionally, this study finds that status consumption is partially related to smartphone purchases, which could also be extended to other technological products categories.
159

Percepção gustativa, consumo e preferencias alimentares de mulheres da 3ª idade : um estudo de caso / Perception taste, consumption and food preferences of women from age 3 rd : a case study

Abreu, Glaucia Maria Navarro de 03 August 2018 (has links)
Orientador : Maria Aparecida Azevedo Pereira da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-03T15:39:04Z (GMT). No. of bitstreams: 1 Abreu_GlauciaMariaNavarrode_M.pdf: 35475994 bytes, checksum: 328339449eb7cfcd19f6fe0868849369 (MD5) Previous issue date: 2003 / Resumo: Indivíduos da terceira idade representam um dos segmentos da população brasileira que mais tem aumentado nos últimos anos. No período entre 2000 e 2050 deverá ocorrer o mais rápido aumento da proporção de idosos brasileiros, a qual passará de 5,1% para 14,2% (Carvalho, 1993). Por este motivo, o envelhecimento passou a ser objeto de cuidado e atenção especiais, que nos dois últimos séculos eram inexistentes. Sabe-se que a qualidade de vida de indivíduos idosos depende de forma marcante de seu estado nutricional. Infelizmente, no Brasil, muitos idosos encontram-se em miséria, impossibilitados de comprar alimentos que permitam uma alimentação de boa qualidade nutricional. Outros moram sozinhos e sofrem isolamento social, o que predispõe o idoso à depressão, problema psicológico comum nesses indivíduos e que traz como conseqüência, significativa perda de apetite (Blaum et aI, 1995). Assim, ocorrências freqüentemente associadas à 33 idade, como perda de cônjuge, isolamento ou falta de integração social, pobreza e depressão são também fatores importantes que concorrem à nutrição inadequada do idoso. Possivelmente, o impacto desses fatores seja ainda maior sobre a população feminina, dado que tradicionalmente mulheres recebem salários inferiores aos homens e, por possuírem maior expectativa de vida, sofrem com mais freqüência os danos psicológicos da perda do cônjuge. Outro motivo freqüentemente associado a problemas nutricionais em idosos são perdas graduais na percepção sensorial que ocorrem durante o processo de envelhecimento, as quais são citadas com freqüência, como responsáveis da diminuição da ingestão de alimentos pelo idoso, o qual passa também a praticar uma dieta monótona já que ele / ela não conseguem perceber adequadamente diferença de sabor entre alimentos (Corwm, 1995). No Brasil ainda são poucas as pesquisas que abordam consumo, preferência e percepção sensorial de idosas com relação a alimentos.Por este motivo, o presente estudo teve como objetivo: i) verificar a adequação nutricional da dieta de mulheres brasileiras da terceira idade e, ii) verificar a perda sensorial de percepção dessas mulheres com relação ao gosto doce, salgado e ácido. Para isto, em um primeiro estudo, inquérito recordatório de 24 horas e um questionário de freqüência de consumo foram aplicados em 94 universitárias da Universidade da 33 Idade da Fundação de Ensino Octávio Bastos, interior de SP, Brasil. Os dados obtidos pela aplicação do inquérito recordatório 24 horas foram analisados utilizando-se o software Virtual Nutri, desenvolvido pela Universidade de São Paulo - Departamento de Saúde Pública - o qual avalia a adequação do consumo energértica e de nutrientes, seguindo as recomendações da RDA (1989). Os dados obtidos através do questionário de freqüência de consumo alimentar foram analisados através de média e frequência de consumo. De um modo geral, os resultados deste estudo indicaram inadequação energética, de vitamina B6, cálcio, magnésio e zinco. As idosas mostraram para esses nutrientes, uma média de adequação inferior a 60% das recomendações para a população em estudo (RDA, 1989). Os nutrientes: proteínas, retinol, vitamina E, tiamina, vitamina C e vitamina B12 obtiveram média de adequação superior a 100% nesta população. Para o estudo sobre a perda de percepção sensorial da terceira idade, testes sensoriais de detecção dos gostos básicos e de potência é (dulcorante, acidulante e de gosto salgado, dos compostos sacarose, ácido cítrico e c1oreto de sódio, respectivamente, foram aplicados tanto em mulheres da 33 idade como em jovens adultas universitárias. Testes sensoriais para se verificar níveis ideais de açúcar em chá mate e suco de laranja, sal em polenta foram realizados de forma comparativa: grupo de mulheres da 33idade x grupo de mulheres jovens adultas. Os resultados obtidos pela equipe de mulheres da 33idade dão suporte ao pressuposto de uma diminuição (P<0,05)da percepção sensorial dos gostos doce e salgado quando concentrações desses compostos encontram-se próximas aos seus limiares de detecção, confmnando outros estudos realizados em indivíduos da 33 idade (Schiffman,1993). Entretanto, em condições suprathreshold, não foram observadas diferenças significativas (PS 0,05)entre o grupo da 3a idade e de jovens adultas. Da mesma forma, em relação à concentração ideal de açúcar em chá marte e suco de laranja, e à concentração ideal de sal em polenta, a análise dos dados obtidos sugeriu não haver diferença (P<0,05)entre jovens adultas e mulheres da 3a idade. Os resultados indicaram entretanto, haver uma menor capacidade das mulheres da 3a idade em gerarem modelos preditivos significativos (P<0,05) envolvendo a concentração do composto no alimento e a percepção sensorial por ele provocada / Abstract: IndividuaIs of the third generation represent the segment of the Brazilian population which has most increased in recent years. Between 2000 and 2003 a rapid increase in the proportion of aged Brazilians is expected to occur, from 5.1% to 14.2% (Carvalho, 1993). Thus aging has become an object of concem and special attention, which was inexistent in the last two centuries. lt is known that the quality of life of the aged is markedly dependent on their nutritional state. Unfortunately many of the aged live in abject misery in Brazil, unable to buy foods permitting good quality nutritional feeding. Others live alone and suffer from social isolation, predisposing them to depression, a common psychological problem in such individuaIs, bringing, as a consequence, a significant loss in appetite (Blaum et al, 1995). Thus occurrences commonly associated with the aged, such as loss of spouse, isolation or lack of social integration, poverty and depression, are factors which contribute to the inadequate nutrition of the aged. The impact of these factors is possibly greater amongst women, who traditionally receive lower salaries than men, and, since they have a longer life expectancy, suffer the psychological damage of losing their spouse with greater frequency. Another motive frequent1yassociated with the nutritional problems of the aged are the gradual losses in sensory perception which occur during the aging process, and which are frequent1y cited as responsible for a decrease in food ingestion by the aged, who start to follow a monotonous diet since he/she can no longer sense much difference in flavor between the foods (Corwin, 1995). In Brazil there are few surveys dealing with consumption, preference and sensory perception amongst the aged with respect to their food. Thus the objective of the present study was: i) veri:tYthe nutritional adequacy of the diet of aged Brazilian women and ii) veri:tYthe loss of sensOl)' perception in these women with respect to sweet, savory and acid flavors. Thus first1y a 24 hour recorded enquiry and a questionnaire on the frequency of consumption were applied to 94 university students of the University for the Third Generation of the Fundação de Ensino Octávio Bastos, in inland São Paulo State, Brazil. The data obtained fTom the 24 hour recorded enquiry were analyzed using the software Virtual Nutri, developed by the Department of Public Health of the University of São Paulo, which evaluates the adequacy of calorie and nutrient consumption according to the RDA recommendations (1989). The data obtained fTomthe questionnaire on the fTequency of food consumption were analyzed according to the means and fTequency of consumption. In general the results of this survey indicated a lack of calories, vitamin B6, calcium, magnesium and zinco For these nutrients, the aged showed a mean consumption 60% below the recommended values for their age group (RDA, 1989). The nutrients protein, retinol, and vitamins E, Bt, C and B12showeded means greater than 100%for this population. To study the loss in sensory perception of the aged, sensory tests were applied for the detection of basic flavors for the sweet, acid and savory potency of the compounds sucrose, citric acid and sodium chloride, applying the test to young adult university students and to aging women. Sensory tests to determine the ideal levels of sugar and salt in matte tea, orange juice and com cake were applied in a comparative form: group of aging women x group ofyoung adults. The results obtained fTomthe panel of aging women support the idea of a decrease (p<0.05) in sensory perception of the flavors sweet and savory when the concentrations of these compounds were near their threshold values, confmning other studies with aging individuaIs (Schiffinan, 1993). However in supra-threshold conditions, no significant (p<0.05) differences were found between the two groups. In the same way, with respect to the ideal concentration of sugar in marte tea and in orange juice, and the ideal salt concentration in com cake, the data analysis suggested no difference (p<0.05) between the two groups. However the results indicate a decrease in the capacity of aging women to create significant predictive models (p<0.05) involving the concentration of a food compound and the sensory perception aroused.Key words: food consumption, sensory perception / Mestrado / Mestre em Alimentos e Nutrição
160

Market Structure and Economic Modeling: A Case Study of the World Zinc Industry

Gupta , Satyadev 08 1900 (has links)
<p> Zinc, a non-ferrous metal, is consumed as an intermediate input in construction and a wide variety of manufacturing industries. Canada, Australia, Peru and Mexico together produce about 55 percent of the total output but absorb only about 8 percent of the total zinc consumed in the free market world. On the other hand, U.S.A., Japan and the E.E.C. countries together share in about 72 percent of the total consumption but produce only 25 percent of the total zinc ores produced in the free market world. These large imbalances in production and consumption of zinc place it in the group of important international primary commodities. The major aims of this study are to provide a systematic understanding of the institutional and behavioral characteristics of the world zinc industry, and to analyse its performance properties in the framework of a formal model of the international market. </p> <p> A detailed study of the organisational structure of the industry reveals that as many as 24 corporate groups (including their multinational operations) share in about 65 percent of the raw zinc produced in the free market world. In the absence of any other information to the contrary, this low degree of concentration in terms of market control is taken as an evidence for the absence of non-competitive behavior on the sellers' side. However, the working of the free market forces has, often, been influenced by the intervention of the U.S. Government through its stockpile program, tariffs, quotas, and other measures for the protection of the domestic industry. This environment, in turn, has enabled the major U.S. producers to exercise some degree of control on the domestic market through the variations in their stocks of zinc and capacity utilisation ratio. However, the world market on the buyers' side consists of a large number of small consumers of zinc providing a competitive environment.</p> <p> A fairly detailed market form of econometric model is built, based on the above institutional framework and relevant technological and behavioral features. An estimated version of the model indicates different systems of lag responses in the structures of demand and supply to the price of zinc, a very poor substitutability on the demand side, free market price as a long-run equilibrator for the U.S. producers' price, and an important influence of the U.S. interventions on the world market. The model meets reasonably well the predictability criterion based on the technique of dynamic simulation. The performance properties of the world zinc industry, analysed through dynamic multiplier simulation technique, show that the industry exhibits a reasonably stable market environment to the exogenous disturbances such as an increase in the activity levels of consumers and variations in the prices of substitutes. It is, however, quite ·sensitive to technological changes in the consumer industries. The stockpile policy of the U.S. Government does not seem to be properly geared to its objectives, and, in general, it seems to have restricted the development of the industry as a whole.</p> <p> Despite the usual limitations of a first systematic study, it is hoped that this work will contribute towards a better understanding of the salient features of the industry, provide a reasonably sufficient scope for broad policy evaluations, and facilitate the forecasting of the behaviour of major market variables.</p> / Thesis / Doctor of Philosophy (PhD)

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