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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.
301

Previsão de longo prazo de níveis no sistema hidrológico do TAIM

Galdino, Carlos Henrique Pereira Assunção January 2015 (has links)
O crescimento populacional e a degradação dos corpos d’água vêm exercendo pressão à agricultura moderna, a proporcionar respostas mais eficientes quanto ao uso racional da água. Para uma melhor utilização dos recursos hídricos, faz-se necessário compreender o movimento da água na natureza, onde o conhecimento prévio dos fenômenos atmosféricos constitui uma importante ferramenta no planejamento de atividades que utilizam os recursos hídricos como fonte primária de abastecimento. Nesse trabalho foram realizadas previsões de longo prazo com antecedência de sete meses e intervalo de tempo mensal de níveis no Sistema Hidrológico do Taim, utilizando previsões de precipitação geradas por um modelo de circulação global. Para realizar as previsões foi elaborado um modelo hidrológico empírico de regressão, onde foram utilizadas técnicas estatísticas de análise e manipulação de séries históricas para correlacionar os dados disponíveis aos níveis (volumes) de água no banhado. Partindo do pressuposto que as previsões meteorológicas são a maior fonte de incerteza na previsão hidrológica, foi utilizada a técnica de previsão por conjunto (ensemble) e dados do modelo COLA, com 30 membros, para quantificar as incertezas envolvidas. Foi elaborado um algoritmo para gerar todas as possibilidades de regressão linear múltipla com os dados disponíveis, onde oito equações candidatas foram selecionadas para realizar as previsões. Numa análise preliminar dos dados de entrada de precipitações previstas foi observado que o modelo de circulação global não representou os extremos observados de forma satisfatória, sendo executado um processo de remoção do viés. O modelo de empírico de simulação foi posteriormente executado em modo continuo, gerando previsões de longo prazo de níveis para os próximos sete meses, para cada mês no período de junho/2004 a dezembro/2011. Os resultados obtidos mostraram que a metodologia utilizada obteve bons resultados, com desempenho satisfatórios até o terceiro mês, decaindo seu desempenho nos meses posteriores, mas configurando-se em uma ferramenta para auxílio à gestão dos recursos hídricos do local de estudo. / Population growth and degradation of water bodies have been pressuring modern agriculture, to provide more efficient responses about the rational use of water. For a better use of water resources, it is necessary to understand the movement of water in nature, where prior knowledge of atmospheric phenomena is an important tool in planning activities that use water as the primary source of supply. In this study were performed long-term forecasts of water levels (seven months of horizon, monthly time-step) in the Hydrological System Taim, using rainfall forecasts generated by a global circulation model as input. To perform predictions was developed an empirical hydrological regression model. This model was developed based on statistical techniques of analysis and manipulation of historical data to correlate the input data available to the levels (volume) of water in a wetland. Assuming that weather forecasts are a major source of uncertainty in hydrological forecasting, we used an ensemble forecast from COLA 2.2 with 30 members to quantify the uncertainties involved. An algorithm was developed to generate all the multiple linear regression models with the available data, where eight candidates equations were selected for hydrological forecasting. In a preliminary analysis of the precipitation forecast was observed that the global circulation model did not achieve a good representation of extremes values, thus a process of bias removal was carried out. Then the empirical model was used to generate water levels forecast for the next seven months, in each month of the period june/2004 to december/2011. The results showed that the methodology used has a satisfactory performance until the lead time three (third month in the future) where the performance starts to show lower values. Beside the sharply lost of performance in the last lead times, the model is a support tool that can help the decision making in the management of water resources for the study case.
302

An Analysis of the Differences between Unit and Integration Tests

Trautsch, Fabian 08 April 2019 (has links)
No description available.
303

Liminality of NHS research ethics committees : navigating participant protection and research promotion across regulatory spaces

Dove, Edward Stellwagen January 2018 (has links)
NHS research ethics committees (RECs) serve as the gatekeepers of health research involving human participants. They have the power to decide, through a regulatory 'event licensing' system, whether or not any given proposed research study is ethical and therefore appropriate to undertake. RECs have several regulatory functions. Their primary function has been to protect the interests of research participants and minimise risk of harm to them. Yet RECs, and other actors connected to them, also provide stewardship for the promotion of ethical and socially valuable research. While this latter function traditionally has been seen as secondary, the 'function hierarchy' is increasingly blurred in regulation. Regulatory bodies charged with managing RECs now emphasise that the functions of RECs are to both protect the interests of research participants, and also promote ethical research that is of potential benefit to participants, science, and society. Though the UK has held in some of its previous regulations (broadly defined) that RECs equally function to facilitate (ethical) health research, I argue that the 'research promotionist' ideology has moved 'up the ladder' in the regulation of RECs and in the regulation of health research, all the way to implementation in law, specifically in the Care Act 2014, and in the regulatory bodies charged with overseeing health research, namely the Health Research Authority. This thesis therefore asks: what impact does this ostensibly twinned regulatory objective then have on the substantive and procedural workings of RECs? I invoke a novel 'anthropology of regulation' as an original methodological contribution, which enables me to study empirically the nature of regulation and the experiences of actors within a regulatory space (or spaces), and the ways in which they themselves are affected by regulation. Anthropology of regulation structures my overall empirical inquiry to query how RECs, with a classic primary mandate to protect research participants, now interact with regulatory bodies charged with promoting health research and reducing perceived regulatory barriers. I further query what this changing environment might do to the bond of research and ethics as seen through REC processes of ethical deliberation and decision-making, by invoking the original concept of 'regulatory stewardship'. I argue that regulatory stewardship is a critical, but hitherto invisible, component of health research regulation, and requires fuller recognition and better integration into the effective functioning of regulatory oversight of research involving human participants.
304

A Bayesian approach for modeling stochastic deterioration

SILVA, Rodrigo Bernardo da 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T17:40:37Z (GMT). No. of bitstreams: 2 arquivo720_1.pdf: 2087569 bytes, checksum: 4e440439e51674690e086dbc501c7a58 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / A modelagem de deterioracão tem estado na vanguarda das analises Bayesianas de confiabilidade. As abordagens mais conhecidas encontradas na literatura para este proposito avaliam o comportamento da medida de confiabilidade ao longo do tempo a luz dos dados empiricos, apenas. No contexto de engenharia de confiabilidade, essas abordagens têm aplicabilidade limitada uma vez que frequentemente lida-se com situacões caracterizadas pela escassez de dados empiricos. Inspirado em estrategias Bayesianas que agregam dados empiricos e opiniões de especialistas na modelagem de medidas de confiabilidade não-dependentes do tempo, este trabalho propõe uma metodologia para lidar com confiabilidade dependente do tempo. A metodologia proposta encapsula conhecidas abordagens Bayesianas, como metodos Bayesianos para combinar dados empiricos e opiniões de especialistas e modelos Bayesianos indexados no tempo, promovendo melhorias sobre eles a fim de encontrar um modelo mais realista para descrever o processo de deterioracão de um determinado componente ou sistema. Os casos a serem discutidos são os tipicamente encontrados na pratica de confiabilidade (por meio de simulacão): avaliacão dos dados sobre tempo de execucão para taxas de falha e a quantidade de deterioracão, dados com base na demanda para probabilidade de falha; e opiniões de especialistas para analise da taxa de falha, quantidade de deterioracão e probabilidade de falha. Estes estudos de caso mostram que o uso de informacões especializadas pode levar a uma reducão da incerteza sobre distribuicões de medidas de confiabilidade, especialmente em situacões em que poucas ou nenhuma falha e observada.
305

Psychologické a sociální aspekty působení cestovní kanceláře / Psychological and social aspects of tour operator's activity

Kaplina, Olesya January 2010 (has links)
This graduation thesis focuses on analyzing a tour operator's supply and it's comparison with the results of empirical research. Trends of demand in tourism industry, preferences and expectations of clients will be compared with the vision of the tour operator on the base of theoretical knowledge and the results of empirical research. To reach improvement of the supply the needed measures will be advised in the end of the thesis. The thesis is divided into two parts, the theoretical base and the empirical research.
306

Requirements engineering in software startups: a qualitative investigation / Engenharia de requisitos em startups de software: uma investigação qualitativa

Jorge Augusto Melegati Gonçalves 06 March 2017 (has links)
Software startups face a very demanding market: they must deliver high innovative solutions in the shortest possible period of time. Resources are limited and time to reach market is short. Then, it is extremely important to gather the right requirements and that they are precise. Nevertheless, software requirements are usually not clear and startups struggle to identify what they should build. This context affects how requirements engineering activities are performed in these organizations. This work seeks to characterize the state-of-practice of requirements engineering in software startups. Using an iterative approach, seventeen interviews were conducted during three stages with founders and/or managers of different Brazilian software startups operating in different market sectors and with different maturity levels. Data was analyzed using grounded theory techniques such open and axial coding through continuous comparison. As a result, a conceptual model of requirements engineering state-of-practice in software startups was developed consisting of its context influences (founders, software development manager, developers, business model, market and ecosystem) and activities description (product team; elicitation; analysis, validation and prioritization; product validation and documentation). Software development and startup development techniques are also presented and their use in the startup context is analyzed. Finally, using a bad smell analogy borrowed from software development literature, some bad practices and behaviors identified in software startups are presented and solutions to avoid them proposed. / Startups de software enfrentam um mercado muito exigente: elas devem entregar soluções altamente inovativas no menor período de tempo possível. Recursos são limitados e tempo para alcançar o mercado é pequeno. Então, é extremamente importante coletar os requisitos certos e que eles sejam precisos. Entretanto, os requisitos de software geralmente não são claros e as startups fazem um grande esforço para identificar quais serão implementados. Esse contexto afeta como as atividades de engenharia de requisitos são executadas nessas organizações. Este trabalho procura compreender o estado-da-prática da engenharia de requisitos em startups de software. Usando uma abordagem iterativa, dezessete entrevistas foram realizados em três diferentes estágios com fundadores e/ou gestores de diferentes startups de software brasileiras operando em diferentes setores e com diferentes estágios de maturidade. Os dados foram analisados usando técnicas de teoria fundamentada como codificação aberta e axial através da comparação contínua. Como resultado, um modelo conceitual do estado-da-prática da engenharia de requisitos em startups de software foi desenvolvido consistindo da suas influências do contexto (fundadores, gerente de desenvolvimento de software, desenvolvedores, modelo de negócio, mercado e ecossistema) e descrição das atividades (time de produto; levantamento; análise, validação e priorização; e documentação). Técnicas oriundas de metodologias de desenvolvimento de software e desenvolvimento de startups também são apresentadas e seu uso em no contexto de startups é analisado. Finalmente, a partir de uma analogia de maus cheiros presente na literatura de desenvolvimento de software, algumas más práticas e maus comportamentos identificados em startups de software são apresentados e algumas sugestões de solução são propostas.
307

The effects of regulation and competition on the housing market from a structural model / Os efeitos da regulação e competição no mercado imobiliário a partir de um modelo estrutural

Silva, Rômullo Carvalho da 03 October 2017 (has links)
Real estate activity is notably influenced by local land use regulation. By acting as redtape costs or explicitly through compensatory payments, such rules typically increase construction costs by reducing supply and increasing demand in the housing market, which leads to higher prices. This is the first study to model the decision-making process of housing supply using a game theoretic approach. To shed light on the roleof regulation and competition in this industry, I employ a static-entry model that incorporates the demand, cost and strategic factors common to the activity. I built aunique data set forthe city of São Paulo, Brazil, with information on the universe ofnew residential buildings launched in the city, along with a history of all licenses requested by the developers tothe government for each project. My empirical results show that the regulation play akey role in developer activity. For the areas with the most intense activity of the city,the bureaucracy in the residential approval process cost annually R$ 47 millions (US$ 14millions) by entrant firm. / A atividade imobiliária é particularmente influenciada pela regulação do uso da terra. Ao agir como \"custos burocráticos\" ou explicitamente por meio de pagamentos compensatórios,essas regras normalmente aumentam os custos de construção ao reduzir a oferta e aumentara demanda de novas residências, o que leva a preços mais altos. Este é o primeiro estudo amodelar o processo de decisão de oferta de residências usando uma abordagem de teoria dos jogos. Para mostrar os efeitos da regulação e da competição nesse setor, eu emprego um modelo de entrada estático que incorpora os fatores de demanda, custo e estratégicos comuns a essa atividade. Eu construí uma base de dados única para a cidade de São Paulo, Brasil, com informações sobre o universo de novos empreendimentos residenciais na cidade, juntamente comum histórico de todas as licenças e alvarás requeridos pelas incorporadoras à Prefeitura para cada projeto. Meus resultados mostram que a regulação tem um papel chave na atividade imobiliária. Para as áreas com atividade mais intensa da cidade, a burocracia no processo de aprovação de novas residências tem um custo média anual de R$ 47 milhões por firma entrante no mercado.
308

PPP模式是推动电子政务平台健康发展的良药吗? --来自华东地区50个城市政务App的面板数据分析

January 2019 (has links)
abstract: 当前各个城市都在努力推动“互联网+政务”的公共服务新模式,打造政府公共服务平台,提供“一站式”的服务资源,以民众需求为中心,解决民众信息查询、政府办事预约、政策咨询等公共活动的需要。可以看出,政务平台给民众的生活带来极大的便利,是当前各地政府响应中央建立“智慧城市”“数字中国”的重要举措。 本课题发现当前的政务平台逐步引入PPP模式,借助社会资源开发政务平台。但是,PPP模式是否有利于政务平台的建设,受到哪些因素的制约,如何更好地利用PPP模式进行开发工作,这些问题在现前的研究中没有得到很好地探索。带着这些问题,本课题对PPP模式在政务平台建设中的作用进行了深入剖析。主要研究内容如下: 在第一部分中,本课题政府公共服务和政务相关理论进行了全面整理,发现政务平台要想走出一条健康发展之路,需要借助社会资源进行市场化,而PPP模式符合当前政务平台建设的需要。本文对PPP模式在国内外电子政务的应用进行了分析,提出了本文的研究主题。 在第二部分中,本文对华东地区50座城市的政务平台进行了调研,对常见问题进行了整理,发现PPP模式已经广泛应用于政务平台建设中,且主要有四种模式,本文对50座城市的政务平台建设情况进行了数据采集,并进行了深入分析。 在第三部分中,结合调研现状和文献研究成果,提出了PPP模式影响政务平台建设的相关假设,并构建了计量模型。通过短面板分析验证假设,并进行了Robust分析,证实结论的普适性。 在第四部分中,本文分析了研究结果,认为政务平台采用PPP模式能够有效促进政务平台的建设水平,提高用户满意度;并且PPP模式与合作企业的估摸、信息的透明程度和平台的交互能力存在显著的交互作用,共同影响用户对政务平台的评价。政府引入PPP模式,充分对接可利用资源,并加强盈利控制,对当前政务平台的建设是具有积极意义的。 / Dissertation/Thesis / Doctoral Dissertation Business Administration 2019
309

The Economics of Information and Spatial Price Behavior: An Empirical Assessment of Producer's Cattle Prices in the Western Region of the USA: 1973-1981

Juan, Maria Lourdes del Rosario 01 May 1983 (has links)
This study is an empirical verification of the theories of the economics of information at the cattle producer's market in the U.S. Western Region. Weekly data on producer's price quotations were obtained from CATTLEFAX for 1973 through 1981. The three major objectives of the research are: first, to determine whether price dispersion exists in the cattle producer's market in the Western Region: second, if significant price dispersion are shown to exist, to determine the nature of the regional price distribution; and third, if price dispersion do exist, to determine the implications of the dispersion relative to competitive structure, efficient informational flows, and relative informational content of said distribution. Price dispersion exists in the cattle producer's market of the Western Region. It is the buyers who "establish" prices and sellers act as price takers. Where heavy trading occurs, information of prices is more efficiently transmitted resulting in a more symmetrical distribution. The composition of the market is relatively stable. however, imperfect information results in splitting the market into high price and low price favoring the better informed. Utah producers are rational in their pricing decisions. Price dispersion can be attributed to the lag in obtaining price information and asymmetry in efficiency of information gathering.
310

Racial Discrimination in Home Ownership: Impact of the 2008 Economic Crisis

Severtson, John 01 January 2019 (has links)
This paper uses regression analysis on a national data set from the United States from 2001-2016 to analyze racial or ethnic group disparities in home ownership between whites and blacks, Asian and Pacific Islanders, Puerto Ricans, Cubans, Mexicans, other Hispanics and American Indians. I employ Integrated Public Use Microdata combined with Bureau of Labor Statistics data and Federal Reserve Economic Data from the Federal Reserve Bank of St. Louis. Controlling for demographic, educational, income and wealth, employment and housing characteristics, I find no significant differences between whites and Asian and Pacific Islanders, Mexicans and American Indians. However, blacks, Puerto Ricans, Cubans and other Hispanics face racial disadvantages in regard to home ownership. All minority racial or ethnic groups, except American Indians, lost home ownership parity to whites from 2007-2011, the years primarily affected by the economic crisis.

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