1000 resultados para mudança climática


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Versão com menu acessível para leitores de tela e vídeo com audiodescrição.

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Nesta tese apresento um estudo detalhado sobre vários aspectos relacionados com a optimização de sistemas híbridos fotovoltaicos-eólicos em zonas insulares de diversidade climática-arquipélago da Madeira que foi desenvolvido no Laboratório Regional de Engenharia Civil e com algumas deslocações no Laboratório de Energia Solar da Universidade de Vigo entre 2002 e 2007. Foi baseado nos conhecimentos adquiridos ao longode 25 anos de prática profissional de estudo, projecto, montagem e monitorização de tecnologias solares e eólicas, para produção de electricidade em locais isolados, bem como pesquisa e análise climatológica. Como resultado final e após a criação de uma base de dados climáticos para fins energéticos, determinámos os dias característicos de radiação solar e temperatura para cada um dos doze meses do ano, nas seis estações meteorológicas estudadas. Estes dias são de grande utilidade também para a elaboração de outros estudos. Após o tratamento dos dados constatou-se que a evolução das temperaturas ao longo do ano, tanto no caso das médias como nas médias dos valores máximos e nas médias dos valores mínimos,segue uma tendência similar em todas as estações. Concluimos que, a altitude é o factor determinante nestas diferenças, de tal maneira que quanto maior for a altitude menor são, em geral, as temperaturas médias. No estudo da irradiação global constatámos que na ilha do Porto Santo há mais 4% de radiação solar que na ilha da Madeira. Já na costa norte da Madeira, mais precisamente em São Jorge a média diária mensal e anual é inferior em cerca de 16.5 % em relação ao Porto Santo. Contudo, a costa sul da Madeira apresenta valores de radiação interessantes para o aproveitamento energético. Na abordagem à produção fotovoltaica e eólica, desenvolvemos um novo conceito que relaciona a produção eléctrica por metro quadrado de terreno horizontal, referente à área dos módulos fotovoltaicos e à área de afectação dos aerogeradores. Este novo conceito permite facilmente comparar sistemas energéticos diferentes utilizando diferentes recursos energéticos, permitindo também comparar a energia eléctrica produzida com a energia solar recebida e, deste modo, extrapolar os resultados para a toda a superfície do arquipélago. Finalmente, no que diz respeito à optimização de sistemas híbridos fotovoltaicos-eólicos nas seis zonas climáticas do arquipélago da Madeira, calculámos a produção eólica diária e a produção média diária para cada um dos doze meses do ano, bem como a média anual, isto por metro quadrado de área varrida pelo rótor do aerogerador, para que os resultados se pudessem comparar com os resultados anteriormente obtidos na produção fotovoltaica, reportados também a metro quadrado de área de módulo. No que concerne à produção máxima e comparativa de sistemas (100% fotovoltaicos e 100% eólicos), estudámos várias hipóteses para que os resultados fossem os mais gerais possíveis, tendo-se chegado à conclusão de que se se relacionar a procura de energia/consumo com a produção anual do sistema híbrido, não é necessário fazer a simulação dos sub-sistemas fotovoltaicos-eólicos em tamanho real, bastando apenas conhecer a proporção exacta destes, e extrapolar os resultados obtidos em percentagem para qualquer dimensão. Da análise comparativa dos resultados da produção energética das diferentes composições percentuais fotovoltaico-eólico, podemos avaliar facilmente o grau de cobertura de energia renovável. Conhecidas as percentagens de cobertura da procura que se obtêm com energias renováveis, é possível definir com segurança as percentagens solar-eólica que oferecem as melhores opções técnicas. Em termos de optimização técnica, concluímos que o único factor que diferencia um sistema híbrido de outro, nos 6 locais estudados, é a área do módulo fotovoltaico e a área varrida pelo rótor do aerogerador. Finalmente, concluímos que os custos das instalações híbridas e do kWh renovável produzido nos locais estudados, diminuem em todos os locais ao diminuir a percentagem do sub-sistema eólico no sistema híbrido fotovoltaico-eólico, sendo o custo mais baixo reportado sempre à Instalação toda solar (100% fotovoltaica).

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Neste estudo aborda-se, de forma descritiva, o processo de mudança de práticas de um professor do ensino secundário, decorrente de uma relação de supervisão gerida pelo investigador. Essa mudança foi no sentido de um processo de ensino informado pela perspectiva construtivista, mais concretamente pela concepção de aprendizagem significativa tal como perspectivada por Ausubel. A elaboração do estudo envolveu várias fases que incluem a formação, a recolha e a análise de dados, a supervisão. A recolha de dados foi feita, por um lado, através de quatro inquéritos, dois para os alunos e dois para o professor, aplicados em dois momentos distintos: antes da mudança do processo de ensino/aprendizagem e após essa mudança e, por outro lado, através da gravação dos relatos do professor durante o processo de mudança. Antes do bloco de aulas relativo ao processo de mudança, professor e supervisor (investigador) abordaram conjuntamente a perspectiva construtivista e a aprendizagem significativa, e planificaram, também juntos, o bloco de aulas. O processo de supervisão foi enquadrado pelo modelo reflexivo. Os dados (dos inquéritos e das gravações) foram sujeitos a análise de conteúdo, tal como perspectivada por Bardin (1979). Verifica-se a existência de mudanças efectivas relacionadas com a melhoria da preparação das aulas, que tornou o professor mais reflexivo, e com a melhoria da relação pedagógica, que proporcionou aos alunos um papel mais activo no processo de ensino e aprendizagem. Conclui-se sobre a pertinência de repensar a formação contínua dos professores, de forma a incluir supervisores nas escolas que acompanhem os professores no sentido de melhorarem as suas práticas.

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Companies have always been organized by processes, often imperceptible to its employees. With the advancement of technology, organizational processes currently run an organization through computers, and thus generate immediate information that is available to each sector. With the objective of seeking business information in real time, the government created the SPED - Public System of Digital, which involves three subsystems, which are the Electronic Invoice, Digital Accounting Bookkeeping and Digital Tax Bookkeeping. This system is revolutionizing the business structures when gathering, in an innovative way, all information and interlinked business processes. For the implementation of SPED, a revision in the organizational processes is required, since the information is generated and is sent online to the government, without mistakes. Thus the study aimed to analyze the change brought about by the implementation of the Public System of Digital SPED in the main business processes. In order to do so, we have performed a multiple case study involving three companies in the state of Para, two operate in wholesale and one explores agribusiness. The Data collection was performed by accounting professionals, IT and managers. According to the results obtained, it was found that in two companies, the IT infrastructure was capable of deploying the new system without major problems, while one company had more difficulties to cope with the new system. However, all companies had to examine its processes to make the customizations needed to fit. It was also observed that there is no IT Governance in two companies. Therefore, we recommend the use of an appropriate model, not only for the implementation of SPED, but as a way to manage and extract better results from investment in information technology

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This research focuses on the fishery activity, aligned to knowledge of past generations, and the transformation to those who depend on this activity for their livelihood, at the seashore community of Pitangui in Extremoz municipality, which lies 40 km away from Natal, seat of the state of Rio Grande do Norte. The intense modernization which has taking place during the last few years may be considered the result of a number of economic, social and cultural factors, as the introduction of new fishery technology. On the other hand, the present study seeks to show how this changing process happened, and to what extent those affected understand and evaluate this transformation. The methodology to carry out the ethnographic work was mainly adopted by qualitative methods and techniques - by participant observation, oral history, photography and the audiovisual records besides reference to data extracted under quantitative methods, as an important instrument of analyses. This induces a conclusion that the transformation of the community is a consequence of the globalized market, though still tied up to specific local relations. The emerging results are: the use of new fishery technology, and new ways of orientation and navigation; the opening to new jobs and occupational activity, the re-order of space s appropriation; changing sociability, larger access to consumer goods, besides bringing on some new conflicts land appropriation and the fishery and the protection of the environment. All this comprehended as a result of the movement of the local relations participating in the global spaces

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Based on climate data and occurrence records, ecological niche models (ENM) are an important opportunity to identify areas at risk or vulnerable to biological invasion. These models are based on the assumption that there is a match between the climatic characteristic of native and invaded regions predicting the potential distribution of exotic species. Using new methods to measure niche overlap, we chose two exotic species fairly common in semi-arid regions of South America, Prosopis juliflora (Sw.) D.C. and Prosopis pallida (H. ; B. ex. Willd) HBK, to test the climate matching hypothesis. Our results indicate that both species occur with little niche overlap in the native region while the inverse pattern is observed in the invaded region on South America, where both species occur with high climatic overlap. Maybe some non-climate factor act limiting the spread of P. pallida on the native range. We believe that a founder effect can explain these similarities between species niche in the invaded region once the seeds planted in Brazil came from a small region on the Native range (Piura in Peru), where both species occur sympatric. Our hypothesis of a founder effect may be evident when we look at the differences between the predictions of the models built in the native and invaded ranges. Furthermore, our results indicate that P. juliflora shows high levels of climate matching between native and invaded ranges. However, conclusions about climate matching of P. pallida should be taken with caution. Our models based on climatic variables provide multiple locations suitable for occurrence of both species in regions where they still don t have occurrence records, including places of high interest for conservation.

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The purpose of this study is to analyze, from the point of view of nurses, changes that took place in the process of providing health services after the introduction of the Family Health Program (FHP). It is na investigation of qualitative nature that uses semi-structured interviews as a main empirical approach tool. Six nurses from the city of Caicó, Rio Grande do Norte, who were working with basic care before the introduction of the FHP, within basic care, were: adscription and ties with the community; hospitality and the humanizacion of care-giving; decrease in cases of inpatient treatment; strengthening of the prevention of injuries and health promotion; improvemente of health indicatiors, finally, actions that point towads meeting the principles of wholeness, equity and universality as a declaration of the Brazilian National Health Care System (SUS). Nevertheless, in spite of all recognizable positive aspects, the FHP has some weaknesses, such as: the difficulty posed by colletive work; the mismatch between professional education and the demands of the current health standard; a poor physical infrastructure of the Basic Health Units; a high heath staff turnover and precarious work conditions. In addition to this, some strategies that can be used to help improve the process of providing health services have been pointed out, such as, coordination between sectors, continuous education, making work conditions less precarious and improving the means whereby heathy service management is conveyed,Tthus, finally, we understand that the FHP does bring forward meaningful changes to the process of provinding health services to strengthen the Brasilian National Health Care System (SUS), in spite of the fact that it lies within a scenario of adversities that can be overcome through the collective endeavor of the several social actors

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This is an exploratory and descriptive study that aimed to investigate the actions of professionals in the context of breastfeeding, on the assumption that the actions taken by employees working together to postpartum and newborn are not competing to effect the distribution of pasteurized human milk so that it meets the needs of infants who depend on it. Thus, the study aimed to analyze the actions of medical and nursing staff of the distribution of pasteurized human milk to the newly born. The investigation was developed by action research in a federal hospital, located in the capital the state of Rio Grande do Norte, Brazil, reference assistance to women during pregnancy, childbirth and postpartum high risk in 2010. Study participants were fifty-five professionals chosen from the following inclusion criteria: to act in the NICU or rooming, being a pediatrician and / or neonatologists, nurses and technical nursing. According to the methodology of action research a questionnaire was applied, techniques in focus groups and courses were developed, and, finally, action evaluation. The project was submitted to the Ethics Committee at the Federal University of Rio Grande do Norte and approved with no protocol 448/2009. The problems identified in the responses issued by the social research were grouped into categories according to the similarity between them. The answer to the question of the survey - How is the need for pasteurized human milk for the newborns in neonatal intensive care unit and rooming identified? - Brought subsidies for action planning and implementation of strategies for change in the practice of professionals working in rooming and ICU. Thus, the study has relevance in social care and, when at the local level, will compete for the distribution pasteurized human milk to take effect as best as possible, as recommended by the Ministry of Health. It is also conceived that, in a macro view of society, it could contribute to minimizing the health problem that involves the child population

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Due to the large amount of television content, which emerged from the Digital TV, viewers are facing a new challenge, how to find interesting content intuitively and efficiently. The Personalized Electronic Programming Guides (pEPG) arise as an answer to this complex challenge. We propose TrendTV a layered architecture that allows the formation of social networks among viewers of Interactive Digital TV based on online microblogging. Associated with a pEPG, this social network allows the viewer to perform content filtering on a particular subject from the indications made by other viewers of his network. Allowing the viewer to create his own indications for a particular content when it is displayed, or to analyze the importance of a particular program online, based on these indications. This allows any user to perform filtering on content and generate or exchange information with other users in a flexible and transparent way, using several different devices (TVs, Smartphones, Tablets or PCs). Moreover, this architecture defines a mechanism to perform the automatic exchange of channels based on the best program that is showing at the moment, suggesting new components to be added to the middleware of the Brazilian Digital TV System (Ginga). The result is a constructed and dynamic database containing the classification of several TV programs as well as an application to automatically switch to the best channel of the moment

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This work presents a proposal of a methodological change to the teaching and learning of the complex numbers in the Secondary education. It is based on the inquiries and difficulties of students detected in the classrooms about the teaching of complex numbers and a questioning of the context of the mathematics teaching - that is the reason of the inquiry of this dissertation. In the searching for an efficient learning and placing the work as a research, it is presented a historical reflection of the evolution of the concept of complex numbers pointing out their more relevant focuses, such as: symbolic, numeric, geometrical and algebraic ones. Then, it shows the description of the ways of the research based on the methodology of the didactic engineering. This one is developed from the utilization of its four stages, where in the preliminary analysis stage, two data surveys are presented: the first one is concerning with the way of presenting the contents of the complex numbers in math textbooks, and the second one is concerning to the interview carried out with High school teachers who work with complex numbers in the practice of their professions. At first, in the analysis stage, it is presented the prepared and organized material to be used in the following stage. In the experimentation one, it is presented the carrying out process that was made with the second year High school students in the Centro Federal de Educação tecnológica do Rio Grande do Norte CEFET-RN. At the end, it presents, in the subsequent and validation stages, the revelation of the obtained results from the observations made in classrooms in the carrying out of the didactic sequence, the students talking and the data collection

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In this work, we analyze the variation and change phenomenon involving the possessive pronouns da gente and nosso(a)(s) in the light of the theoretical referentials of the North-american linguistic functionalism and of the variationist sociolinguistics. At first we present the phenomenon itself, highlighting the fact that few studies have considered it as an object, gap which we will try to fill in with our contribution. In the following chapter, we emphasize concepts and principles of the functionalism and the sociolinguistics that are used as our background for the data analysis. In the third chapter, we present what the normative grammars inform about our object of study, besides synthesizing some works on variation and change involving the personal pronouns nós and a gente. In the following chapter, we analyze the data. We used data from the Discurso & Gramática a língua falada e escrita na cidade do Natal (FURTADO DA CUNHA, 1998) corpus. In this chapter we present the results for the groups of social and linguistic factors which we can control. Grounded on these results, we specify the preferential contexts for employing the pronouns da gente and nosso(a)(s) and we observe that the social motivations, the valorization credited to the forms and the identity marks underly the restrictions exercised in their use by social factor groups, besides obtaining signs of ongoing changes in apparent time (from the age factor groups) and possible use specializations of each form, what helped us verify the course of the grammaticalization process of the referred pronouns in the community of Natal. In the sixth chapter, we make some considerations on the teaching of grammar and propose activities which can be carried on in the classroom involving the possessive pronouns da gente and nosso(a)(s) considering the variation and change issue