As estações de tratamento de água - ETAs são fundamentais para a melhoria do saneamento ambiental de um país. No Brasil, a avaliação dos impactos ambientais negativos em ETAs se limita normalmente aos resíduos gerados no tratamento da água. As alterações ambientais decorrentes da construção e operação são desconsideradas na escolha das tecnologias, fato que podem prejudicar o alcance da sustentabilidade ambiental. O trabalho desenvolveu um método baseado na adaptação do Método Battelle-Columbus visando a seleção das tecnologias de tratamento de água e dos seus resíduos conforme o critério de impacto ambiental mínimo. O método é válido para comunidades brasileiras de pequeno e médio porte, as quais podem ser beneficiadas com vazões de projeto das ETAs entre 10 L/s e 100 L/s. As combinações dos processos e operações de tratamento nas ETAs e estações de tratamento dos resíduos- ETRs- para cinco diferentes vazões de projeto (10, 20, 40, 70 e 100 L/s) possibilitaram a avaliação de 205 projetos - 180 projetos extraídos de Sabogal Paz (2007; 2010) e 25 elaborados nesta pesquisa com o filtro ascendente em areia grossa na ETA de dupla filtração (DF2). Apenas os impactos ambientais negativos foram considerados na avaliação ambiental. A estimativa da magnitude de cada aspecto ambiental foi baseada nos quantitativos referentes à construção (requerimentos de área, concreto, chapa de aço, meio filtrante e camada suporte) e operação (consumo de energia elétrica e produtos químicos, geração de resíduos líquidos e sólidos) das ETAs e ETRs. Os resultados foram condizentes com a literatura, pois as ETAs menos robustas apresentaram um menor potencial de degradação e as tecnologias com maior área de implantação e consumo de energia elétrica foram mais impactantes. De fácil interpretação, o método é uma ferramenta que auxilia na tomada de decisão das ETAs a serem instaladas nos municípios brasileiros e que contribui para a mudança na abordagem normalmente adotada na seleção das tecnologias de tratamento de água. Com a questão ambiental como parte integrante do processo de escolha, uma visão mais abrangente e sustentável é alcançada para o setor de saneamento no país. / The water treatment plants (WTPs) are fundamental for the improvement of the environmental sanitation in a country. In Brazil, the negative environmental impacts assessment is usually limited in to the sludge produced in water treatment processes. Environmental impacts that occur during construction and operation of water treatment plants are not considered in the selection of technologies, what might prejudice the achievement of environmental sustainability. This research has developed a method based on the adaptation of the Method Battelle-Columbus to select the technologies for water treatment and sludge, according to the minimum environmental impact criteria. The method is effective for small and medium Brazilian communities of the country that can benefit with project flows that uses project flows of WTP between 10 and 100 L/s. Combinations of treatment processes and operations in WTPs and in waste treatment plants, for five different project flows (10, 20, 40, 70 and 100 L/s) enabled the evaluation of 205 projects- 180 projects according to Sabogal Paz (2007, 2010) and 25 projects were elaborated in this research with coarse sand upflow filter on the WTP of double filtration (DF2). Only the negative environmental impacts have been considered in the environmental assessment. The estimation of the magnitude of each environmental aspect was based on quantitative concerning the construction (area requirements, concrete, steel, filter media and support layer) and operation (electric energy consumption and chemicals, liquid and solid residue generation) of WTPs and waste treatment plants. The results were consistent with the literature because the less robust WTPs had a lower potential of degradation and the technologies with greater implantation area and electric energy consumption were more impactful. Easy to be interpreted, the method is a tool that can assist in decision making of WTPs to be installed in Brazilian municipalities and contributes to the change in the approach usually adopted in the technologies selection. On the integration of environmental issues as part of the selection process, a more comprehensive and sustainable solution is achieved to the sanitation sector in the country.

As estações de tratamento de água - ETAs são fundamentais para a melhoria do saneamento ambiental de um país. No Brasil, a avaliação dos impactos ambientais negativos em ETAs se limita normalmente aos resíduos gerados no tratamento da água. As alterações ambientais decorrentes da construção e operação são desconsideradas na escolha das tecnologias, fato que podem prejudicar o alcance da sustentabilidade ambiental. O trabalho desenvolveu um método baseado na adaptação do Método Battelle-Columbus visando a seleção das tecnologias de tratamento de água e dos seus resíduos conforme o critério de impacto ambiental mínimo. O método é válido para comunidades brasileiras de pequeno e médio porte, as quais podem ser beneficiadas com vazões de projeto das ETAs entre 10 L/s e 100 L/s. As combinações dos processos e operações de tratamento nas ETAs e estações de tratamento dos resíduos- ETRs- para cinco diferentes vazões de projeto (10, 20, 40, 70 e 100 L/s) possibilitaram a avaliação de 205 projetos - 180 projetos extraídos de Sabogal Paz (2007; 2010) e 25 elaborados nesta pesquisa com o filtro ascendente em areia grossa na ETA de dupla filtração (DF2). Apenas os impactos ambientais negativos foram considerados na avaliação ambiental. A estimativa da magnitude de cada aspecto ambiental foi baseada nos quantitativos referentes à construção (requerimentos de área, concreto, chapa de aço, meio filtrante e camada suporte) e operação (consumo de energia elétrica e produtos químicos, geração de resíduos líquidos e sólidos) das ETAs e ETRs. Os resultados foram condizentes com a literatura, pois as ETAs menos robustas apresentaram um menor potencial de degradação e as tecnologias com maior área de implantação e consumo de energia elétrica foram mais impactantes. De fácil interpretação, o método é uma ferramenta que auxilia na tomada de decisão das ETAs a serem instaladas nos municípios brasileiros e que contribui para a mudança na abordagem normalmente adotada na seleção das tecnologias de tratamento de água. Com a questão ambiental como parte integrante do processo de escolha, uma visão mais abrangente e sustentável é alcançada para o setor de saneamento no país. / The water treatment plants (WTPs) are fundamental for the improvement of the environmental sanitation in a country. In Brazil, the negative environmental impacts assessment is usually limited in to the sludge produced in water treatment processes. Environmental impacts that occur during construction and operation of water treatment plants are not considered in the selection of technologies, what might prejudice the achievement of environmental sustainability. This research has developed a method based on the adaptation of the Method Battelle-Columbus to select the technologies for water treatment and sludge, according to the minimum environmental impact criteria. The method is effective for small and medium Brazilian communities of the country that can benefit with project flows that uses project flows of WTP between 10 and 100 L/s. Combinations of treatment processes and operations in WTPs and in waste treatment plants, for five different project flows (10, 20, 40, 70 and 100 L/s) enabled the evaluation of 205 projects- 180 projects according to Sabogal Paz (2007, 2010) and 25 projects were elaborated in this research with coarse sand upflow filter on the WTP of double filtration (DF2). Only the negative environmental impacts have been considered in the environmental assessment. The estimation of the magnitude of each environmental aspect was based on quantitative concerning the construction (area requirements, concrete, steel, filter media and support layer) and operation (electric energy consumption and chemicals, liquid and solid residue generation) of WTPs and waste treatment plants. The results were consistent with the literature because the less robust WTPs had a lower potential of degradation and the technologies with greater implantation area and electric energy consumption were more impactful. Easy to be interpreted, the method is a tool that can assist in decision making of WTPs to be installed in Brazilian municipalities and contributes to the change in the approach usually adopted in the technologies selection. On the integration of environmental issues as part of the selection process, a more comprehensive and sustainable solution is achieved to the sanitation sector in the country.

Made available in DSpace on 2015-04-11T14:02:44Z (GMT). No. of bitstreams: 1 aurelio.pdf: 7052556 bytes, checksum: 209649285da9d7e9789f5576368e72c7 (MD5) Previous issue date: 2013-03-26 / The quality of software design is directly related to the decisions taken during its execution, because wrong decisions may cause significant damage in a software project. Among the decisions to be performed by a software engineer, an important one would be the selection of technologies to be applied to software projects. Usually, these decisions are made taking into account the experience of the professionals involved in the task. Thus, we limit the exploration of other possibilities that could be most appropriate for such scenario, what could be offered by a scientific approach to support this decision making. This thesis presents a framework for instantiation of software technologies selection techniques by using search-based strategies. For this, the Software Technologies Selection Problem (STSP) was modeled as a combinatorial optimization problem (Minimum Dominanting Set) with the purpose of to attend different and real scenarios of Software Engineering. The proposed framework for the STSP was idealized as a mechanism to support software engineers who are not able to use other generic optimization frameworks in a software project due to tight deadlines and limited resources. It was designed to be integrated with the main meta-heuristic optimization frameworks, such as JMetal and Opt4J, that implement a large number of meta-heuristics. To analyze the feasibility of the proposed modeling and the developed framework, two case studies were conducted in complex and real optimization problems: (i) selection of model-based testing techniques; (ii) selection of requirements elicitation technique for critical embedded systems. The studies were performed using different meta-heuristics and their results indicate their feasibility to support the selection of software technologies. / A qualidade de um projeto de software está diretamente relacionada com as decisões tomadas durante suas diversas fases, pois decisões equivocadas podem causar danos significativos no projeto. Entre as decisões de um engenheiro de software, pode ser citada a escolha de tecnologias a serem aplicadas em um projeto de software. Geralmente estas decisões são tomadas levando-se em conta a experiência dos profissionais envolvidos nas tarefas. Assim, deixa-se de explorar outras soluções mais adequadas para tal cenário, algo que uma abordagem científica de apoio a tal seleção poderia oferecer. O trabalho apresenta um framework para instanciação de técnicas de seleção de tecnologias de software baseado em estratégias de busca. Para isso, o Problema de Seleção de Tecnologias de Software, do inglês Software Technologies Selection Problem (STSP) foi modelado como um problema de otimização combinatória (Conjunto Dominante Mínimo) com o objetivo de atender diferentes cenários reais de Engenharia de Software. O framework proposto para STSP foi idealizado como um mecanismo de apoio aos engenheiros de software que possuiriam dificuldades em usar outros frameworks de otimização genéricos durante um projeto de software, devido a prazos curtos e recursos limitados. Tal framework foi desenvolvido para ser integrado com os principais frameworks de meta-heurística de otimização identificados na literatura técnica, como JMetal e Opt4J, que implementam um grande número de meta-heurísticas. Para analisar a viabilidade da modelagem proposta para o STSP e do framework desenvolvido, foram realizados dois estudos de casos em problemas de otimização do mundo real: (i) seleção de técnicas de teste baseado em modelos; (ii) seleção de técnicas de elicitação de requisitos para sistemas embarcados. Os estudos foram realizados utilizando diferentes meta-heurísticas. Os resultados indicam sua viabilidade de apoio à seleção de tecnologias de software.

Web development is receiving increasing attention among all kinds and sizes of companies. Web presentation has become a hygiene factor for companies nowadays. Fortunately, nowadays web developers can choose from a great number of ready-made technologies instead of developing everything from scratch. However, web development technologies have evolved much in the past 20 years. Due to the increased complexity and diversity of the alternatives, it is getting more and more difficult for companies to make an overall good choice of technologies, especially small and medium-sized enterprises (SMEs) that usually do not have resources to make a thorough research before choosing. This thesis creates WeTS - Web Technology Stack Guidelines, which contains three parts: process, algorithm and software quality characteristics. By following WeTS, inexperienced web developers, especially in SMEs, can select web technology stacks in an optimal way. Meanwhile, WeTS could be used for experienced practitioners and researchers as a reference to have an overview about modern web development technologies. Based on WeTS Guidelines, this thesis evaluated a number of technology stacks. Then a case study was performed with a startup company named Sqore. By comparing WeTS with Sqore’s technology selection process step by step, this thesis evaluated WeTS Guidelines.

Energy is essential for economic development in Africa. The current electrification figures show that countries in sub-Saharan Africa are facing major challenges in reaching positive economic growth and supplying basic energy services to rural communities. Sustainable energy technologies are available and can be used to great effect in Africa to alleviate this problem. Sustainable energy technologies can contribute to job creation and economic development. The implementation of renewable energy technologies in sub-Saharan Africa to date however has not always been successful due to both technical and non-technical factors. Prior to this study a comprehensive framework of factors to select renewable energy technologies did not exist. The purpose of this research was to develop such a framework and to validate it by means of empirical research. Triangulation of methodologies was used to determine the framework of factors. The analysis of the literature investigated renewable energy technologies and their application, the challenges in renewable energy technologies for implementation in Africa and the selection methods in the fields of project, portfolio, programme and technology management. This was followed by a focus group with three experts in which thirty eight factors that need to be taken into account during the selection of renewable energy technologies in Africa were identified. The factors identified by the focus group were confirmed and the eleven most applicable factors were selected during a two-round Delphi study. Finally case studies on the implementation of renewable energy technologies were undertaken in three countries. These case studies confirmed the eleven factors identified during the Delphi study and identified a further two factors which needed to be added to the framework. The final framework proposed in this study consists of thirteen factors that need to be considered before deciding on the technology appropriate for a specific implementation. For the implementation of the technology to succeed, it must be ensured that the technology can be maintained and supported on site over the life cycle of the technology, and that sufficient skills and resources exist to implement and maintain the technology. Sites for implementation of the technology must be selected in places where local champions exist to continue supporting the technology after the implementing agency has left, the community has the will to adopt the technology in the long term, sites are available for implementing pilot sites and sufficient sites with the correct characteristics are available for long term implementation. The technology must also contribute to economic development by creating jobs or improving the economic situation of households, and financing must be made available to ensure large scale adoption. Local businesses which aid with implementation need to have business management and technical skills as well as the financial capacity to implement the technology. Government support of the implementation of the technology is essential and the environmental benefits of the technology must be clear from the outset. This report presents a framework that includes both the criteria and measures to be used for the selection of renewable energy technologies in Africa. Further work is required to implement these criteria and measures in a selection methodology. / Thesis (PhD)--University of Pretoria, 2011. / Graduate School of Technology Management (GSTM) / unrestricted

The application of new technologies into products allows manufacturers to differentiate their products and fulfil customer requirements. A method to assess the impact of technologies on the fulfilment of customer requirements has been investigated in this research. The main focus is the application of advanced technologies, which may be still in the concept phase, to complex systems using automotive engines as case studies. In these systems the customer will not directly interact with the technologies but the technologies are applied to deliver the range of customer requirements individually or collectively. A standard tool, Quality Functional Deployment (QFD) has been adopted to capture the customer requirements. As all the technology combinations cannot be assessed experimentally due to resource limitations, expert opinion has been employed. A questionnaire has been developed to capture the experts’ opinions of the performance of the technologies in a non-linear Likert-type scale. The combination of expert opinion, where the experts are specialists in a range of engineering disciplines, has been considered and analysis methods incorporating opinion weighting have been developed that parallel established expert opinion analysis methods used for subjective probability risk analysis. The analysis methods enabled different technology combinations to be assessed and customer requirements for different target products to be incorporated to provide a route for optimum technology selection to fulfil customer requirements. A pilot study and two case studies were used to investigate the methodology with Customer feedback used to validate the output in one of the case studies. The research has shown that the Customer Focussed Technology Selection framework and methodology developed in this thesis is a new approach to selecting technologies. The case studies have demonstrated it is an effective framework for evaluating the impact of low technology-readiness-level technologies in complex systems on the Customer. The methodology is suitable for application in technology development processes such as the Jaguar Land Rover TCDS process to support the initial technology selection. / Jaguar Land Rover

A publicação da Norma de Desempenho (ABNT NBR 15.575:2013) e a intensificação das discussões sobre o meio ambiente têm trazido ainda mais destaque para as demandas de desempenho, sustentabilidade e construtibilidade nos projetos de edifícios. Se a inserção dessas demandas em projeto é um desafio, sua obtenção durante a execução do edifício é ainda mais difícil, sobretudo ao se considerar o processo tradicional que ainda domina a produção. Por outro lado, a industrialização do processo construtivo, facilitada pela utilização de tecnologias pré-fabricadas, tem potencial de atender às exigências de desempenho, sustentabilidade e construtibilidade. O arquiteto, enquanto profissional atuante desde o início do processo de projeto, é protagonista da seleção tecnológica, com capacidade de influenciar na adoção de um processo produtivo mais industrializado. Para discutir como o arquiteto pode melhorar sua postura frente às demandas de desempenho, sustentabilidade e construtibilidade, ocupando seu papel de agente integrador no processo de projeto, este trabalho aborda as tecnologias construtivas pré-fabricadas para vedações verticais externas (VVE) de edifícios em estrutura metálica. O objetivo principal deste trabalho é propor diretrizes para seleção tecnológica de VVE de edifícios em estrutura metálica, para o desenvolvimento do projeto de arquitetura, considerando os objetivos do empreendimento e as exigências relacionadas a desempenho, sustentabilidade e construtibilidade. A realização deste trabalho adota duas estratégias de pesquisa: revisão bibliográfica e entrevistas com projetistas de arquitetura e incorporador, com experiência na adoção de estrutura metálica e tecnologias pré-fabricadas de VVE em seus projetos. Como resultado, são propostas: diretrizes voltadas para o processo de projeto de arquitetura, incluindo recomendações para a organização da empresa de projeto que busca tomar decisões sobre tecnologias de VVE pautada em requisitos técnicos; diretrizes para identificar se o empreendimento está inserido em \"nichos estratégicos\" e se o \"ambiente\" para sua realização é favorável à adoção de tecnologias construtivas pré-fabricadas; e diretrizes para atendimento às exigências de desempenho, sustentabilidade, construtibilidade e legislação e normas técnicas a serem seguidas pelos projetistas de arquitetura. Conclui-se que, para responder às demandas de desempenho, sustentabilidade e construtibilidade, buscando adotar tecnologias construtivas pré-fabricadas de VVE, são necessários ao projetista de arquitetura: participação, de fato, na etapa de execução do edifício; estabelecimento de parcerias com agentes envolvidos no processo do empreendimento; manter-se atualizado quanto à legislação e normas técnicas (que têm revelado a tendência de não restringir ao uso de tecnologias construtivas tradicionais); especificar por desempenho as tecnologias de VVE adotadas em projeto; acompanhar a evolução das informações sobre o impacto ambiental gerado pelas tecnologias de VVE; e adotar os princípios de Coordenação Modular nos projetos. / The publication of NBR 15575: 2013 and the growing discussion about environment have brought even more emphasis on some specific demands, such as performance, sustainability and constructability in building projects. Considering that including these demands on design is a challenge, during the building construction is even more difficult, especially regarding the traditional process, which still dominates the production. On the other hand, the industrialization of construction, facilitated by usage of prefabricated technology, has potential to meet performance, sustainability and constructability requirements. The architect, an active professional since the beginning of design process, is the protagonist of technology selection and able to influence the choice for a more industrialized construction process. In order to discuss how an architect could improve his job when it comes to performance, sustainability and constructability demands, assuming an integrating agent role on design process, this research approaches the prefabricated technologies for external walls of steel structural buildings. The main purpose of the research is to propose guidelines for technology selection of external walls of steel structural buildings, aiming the architectural design development, considering the project goals and requirements related to performance, sustainability and constructability. Therefore, two research strategies have been chosen: literature review and interviews with architectural designers and developer, experienced in adopting steel structure and prefabricated technologies for external walls on their projects. As a result of this, it is proposed: guidelines oriented for the architectural design process, including recommendations to organize the design company which seeks for selecting technologies for external walls driven by technical requirements; guidelines to identify if the project is included on \"strategic segments\" and if the \"environment\" for its execution is advantageous to the adoption of prefabricated building technologies; and guidelines to meet performance, sustainability, constructability, legislation and technical standards requirements to be followed by architectural designers. In conclusion, to meet performance, sustainability and constructability demands, aiming the adoption of prefabricated building technologies for external walls, there are some specific needs for architectural designers: active participation on building execution phase; establishing partnerships with stakeholders during the development process; be up to date on the legislation and technical standards (which have been showing a trend to do not restrict the usage of traditional building technologies); to specify by performance the technologies for outside walls chosen on the project; follow the information development about environmental impact generated by outside wall technologies; and adopt the principles of Modular Coordination on the projects.

Os investimentos no setor de água potável no Brasil, apesar de significativos, ainda não apresentam os resultados esperados na melhoria da saúde e da qualidade de vida da população, especialmente nas pequenas comunidades do país. A aplicação de recursos continuará limitada enquanto não forem fortalecidos os aspectos técnicos, econômicos, institucionais, ambientais, sociais e culturais que permitam a seleção de obras sanitárias eficientes e sustentáveis. Neste contexto, foi desenvolvido um modelo conceitual de seleção de tecnologias de tratamento de água constituído por 17 sub-níveis que progressivamente \"filtram\" as opções tecnológicas aplicáveis em comunidades brasileiras inferiores a 20.000 habitantes. Os aspectos envolvidos no modelo se relacionam: i) ao risco presente na fonte de abastecimento superficial; ii) à eficiência das tecnologias para eliminar ou reduzir o risco a valores de acordo à Portaria no 518 (2004); iii) ao tratamento, aproveitamento e disposição dos resíduos gerados e iv) aos custos dos sistemas com vazões de projeto de 10 a 40 L/s. As principais conclusões da pesquisa foram: i) a aplicabilidade do modelo está restrita à estações de tratamento de água - ETAs que cumprem todos seus requisitos de domínio, ii) os valores-limite das variáveis de risco podem conduzir o engenheiro a uma seleção preliminar das possíveis alternativas de tratamento; entretanto, somente a partir de estudos de tratabilidade da água e de testes em instalação piloto será possível definir a ETA mais conveniente, iii) as seleções das tecnologias para tratamento, aproveitamento e disposição do resíduo não devem ser avaliadas de forma independente às empregadas nas ETA; iv) Os custos calculados pelo modelo dificilmente podem ser comparados com sistemas já existentes; v) os resultados do modelo variam em função dos dados de entrada; assim, o usuário deve ter consciência da qualidade da informação fornecida para obter resultados satisfatórios. / Despite being significant the investments in the brazilian drinking water sector still have not presented the expected results regarding the improvement of both health and population\'s life quality, especially in the small communities of the country. The application of resources will continue limited while the technical, economical, institutional, environmental, social and cultural aspects that allow for the selection of efficient and maintainable sanitary works are not strengthened. In this context, a conceptual model to select technologies for water treatment has been developed. It consists of 17 sub-levels that progressively \"filter\" the applicable technological options in brazilian communities of under 20.000 inhabitants. The aspects involved are related to: i) the risk present in the source of superficial supply; ii) the efficiency of the technologies to lither eliminate or reduce the risk to the values according law no 518 (2004); iii) the treatment, use and disposition of the generated residues and iv) the costs of the systems with project flows from 10 L/s to 40L/s. The main conclusions of the research were: i) the applicability of the model is restricted to water treatment plants - WTPs that accomplish all their domain requirements, ii) the limit values of the risk variables can lead the engineer to a preliminary selection of the possible treatment alternatives; however, only from studies of water treatment and tests in pilot installations it will be possible to define the most convenient WTP, iii) the selections of the technologies for treatment, use and disposition of residues should not be appraised in an independent way of the ones employed in WTPs, iv) the costs calculated by the model can hardly be compared with systems already existent; v) the results of the model vary in function of the input data; therefore, the user should be aware of the quality of the information supplied to obtain satisfactory results.

Las redes inal´ambricas actuales exhiben caracter´ısticas heterog´eneas de acceso m´ultiple mediante el despliegue, la coexistencia y la cooperaci´on de varias Tecnolog ´ıas de Acceso Radio (RAT2). En este escenario, la prestaci´on de servicios multimedia garantizando una cierta calidad de servicio (QoS3) es obligatoria. El objetivo global de las redes heterog´eneas de acceso inal´ambrico consiste en sustentar la realizaci´on del concepto ABC (del ingl´es Always Best Connected), en el que un usuario est´a siempre conectado a la RAT que mejor satisface sus necesidades de servicio en cualquier momento, en cualquier lugar, de cualquier modo. En este sentido, las estrat´egias de gesti´on de recursos radio comunes [del ingl´es, Common Radio Resource Management (CRRM)] se dise˜nan para proporcionar una utilizaci´on eficiente de los recursos radio y de espectro radioel´ectrico dentro de la red heterog´enea, ofreciendo un mejor rendimiento en comparaci´on con la realizaci´on independiente de RRM en cada RAT. Adem´as, los recursos de espectro asignados a cada una de las RATs deben ser utilizado de manera eficiente, ya que se trata de un recurso escaso y costoso. En este sentido, conceptos y metodolog´ıas de radio cognitiva (del ingl´es Cognitive Radio o CR) se han aplicado a la gesti´on del espectro, permitiendo una compartici´on dinamico-oportunista del mismo. En estos casos, el espectro sujeto a licencia se abre hacia el acceso de usuarios sin licencia siempre que no perjudiquen y que el funcionamiento libre de interferencias est´e garantizado. Esta tesis analiza estrategias de gesti´on de recursos radio y de espectro para ofrecer un uso mayor y eficiente de los escasos recursos radio y de espectro con el objetivo final de aumentar al m´aximo la capacidad de usuario, garantizando los requerimientos de QoS. En concreto, estas tesis se centra primero en como seleccionar una RAT al inicio de una llamada/sesi´on (en adelante, selecci´on inicial de RAT) en una red de acceso heterog´enea. Un modelo de Markov ha sido desarrollado para definir la asignaci´on de m´ultiples servicios (multi-servicio) en m´ultiples RATs (multi-acceso). En este marco, varias pol´ıticas de selecci´on de RAT son propuestas y evaluadas, gen´ericamente clasific´andose en pol´ıticas basadas en servicio (SB4) y basadas en balanceo de carga (LB5). Adem´as, el rendimiento de las pol´ıticas de selecci´on de RATs en escenarios de acceso limitado debido a la deficiente cobertura radio, la falta de disponibilidad de terminales multi-modo y la incompatibilidad entre RAT y servicios tambi´en es evaluada. Principios espec´ıficos para la asignaci´on de servicios a RATs ser´an provistos en los escenarios antes mencionados con el objetivo general de aumentar la capacidad de usuarios, garantizando los requisitos m´ınimos de calidad de servicio. Finalmente, la congesti´on en el acceso radio tambi´en se trata en este escenario multi-acceso/multi-servicio y el impacto de la selecci´on de RAT evaluado. Los principios para la asignaci´on inicial de RAT con tal de evitar la congesti´on radio ser´an tambi´en proporcionados. En segundo lugar, esta tesis investiga sobre la forma de maximizar el uso eficiente del espectro sujeto a licencia (o licenciado) por medio del acceso din´amicooportunista de espectro a usuarios sin licencia. En este sentido, se concibe un modelo de Markov para captar el problema del uso compartido de espectro entre usuarios con y sin licencia. Un modelo basado en sensado de espectro se propone con el fin de detectar porciones de espectro no utilizados (en ingl´es white spaces) que pueden ser usados por los usuarios sin licencia mientras este siga libre. En este marco, los beneficios obtenidos de la compartici´on del espectro son investigados y las ventajas que implican evaluadas. En concreto, se eval´ua el rendimiento obtenido al ajustar el punto de funcionamiento (en ingl´es operating point ) del mecanismo de sensado, el cual determina los errores de no-detecci´on y falsa-alarma. Por otra parte, sistemas de canalizaci´on de espectro fijos versus adaptativos ser´an propuestos y analizados bajo dos disciplinas de servicio diferentes, cuya duraci´on (o tiempo de permanencia en el sistema) esta basada en tiempo y en contenido respectivamente. / Current wireless networks exhibit heterogeneous multi-access features by means of the coexisting and cooperative deployment of several Radio Access Technologies (RATs). In this scenario, the provision of multimedia services with ensured Quality of Service (QoS) is mandatory. The overall goal of heterogeneous wireless access networks is to enable the realization of the Always Best Connected concept in which a user is seamlessly connected to the RAT best suiting its service requirements anytime, anywhere, anyhow. In this sense, Common Radio Resource Management (CRRM) strategies are devoted to provide an efficient utilization of radio resources within the heterogeneous network offering improved performances as opposed to performing stand-alone RRM in each RAT. In addition, allocated spectrum resources to each RAT must be efficiently utilized since it is a scarce and expensive resource. In this respect, cognitive radio concepts and methodologies have been applied to spectrum management by enabling dynamic/opportunistic spectrum sharing. In these scenarios, licensed spectrum is opened towards unlicensed access provided a non-harmful operation is guaranteed. This dissertation discusses both radio resource and spectrum management strategies to provide an utmost and efficient use of scarce radio/spectrum resources with the overall goal of maximizing user capacity while guaranteeing QoS constraints.Specifically, the thesis is first focused on how to select an appropriate RAT upon call/session initiation (henceforth, initial RAT selection) in a heterogeneous access network. A Markovian framework is developed to such extent supporting the allocation of multiple service-type users (multi-service) on multiple RATs (multi-access). Under this framework, several RAT selection policies are proposed and evaluated, broadly categorized into service-based (SB) and load-balancing (LB). In addition, the performance of RAT selection policies in access-limited scenarios due to poor radio coverage, non multi-mode terminal availability and RAT-service incompatibility is also evaluated. Specific guiding principles for the allocation of services on several RATs are provided in the abovementioned scenarios with the overall goal of increasing user capacity while guaranteeing minimum QoS requirements. Finally, radio access congestion is also addressed in this multi-access/multi-service scenario and the impact RAT selection assessed. Suitable allocation principles avoiding congestion are also provided.Secondly, this dissertation investigates on how to efficiently maximize the use of licensed spectrum by means of dynamic/opportunistic unlicensed spectrum access. Hereof, a Markovian framework is also devised to capture the problem of licensed spectrum sharing towards unlicensed users. A sensing-based spectrum awareness model is proposed in order to detect unused spectrum (so-called white spaces) which may be accessed by unlicensed users while remaining unused. Under this framework, the benefits of spectrum sharing are investigated and the involved gains assessed. Specifically, the sensing-throughput tradeoff and the adjustment of the sensing mechanism’s operating point, which tradeoffs missed-detection and false-alarm errors, is evaluated. Moreover, fixed vs. adaptive spectrum channelization schemes are proposed and analyzed under two different service disciplines considering time-based and volume-based content delivery.

A publicação da Norma de Desempenho (ABNT NBR 15.575:2013) e a intensificação das discussões sobre o meio ambiente têm trazido ainda mais destaque para as demandas de desempenho, sustentabilidade e construtibilidade nos projetos de edifícios. Se a inserção dessas demandas em projeto é um desafio, sua obtenção durante a execução do edifício é ainda mais difícil, sobretudo ao se considerar o processo tradicional que ainda domina a produção. Por outro lado, a industrialização do processo construtivo, facilitada pela utilização de tecnologias pré-fabricadas, tem potencial de atender às exigências de desempenho, sustentabilidade e construtibilidade. O arquiteto, enquanto profissional atuante desde o início do processo de projeto, é protagonista da seleção tecnológica, com capacidade de influenciar na adoção de um processo produtivo mais industrializado. Para discutir como o arquiteto pode melhorar sua postura frente às demandas de desempenho, sustentabilidade e construtibilidade, ocupando seu papel de agente integrador no processo de projeto, este trabalho aborda as tecnologias construtivas pré-fabricadas para vedações verticais externas (VVE) de edifícios em estrutura metálica. O objetivo principal deste trabalho é propor diretrizes para seleção tecnológica de VVE de edifícios em estrutura metálica, para o desenvolvimento do projeto de arquitetura, considerando os objetivos do empreendimento e as exigências relacionadas a desempenho, sustentabilidade e construtibilidade. A realização deste trabalho adota duas estratégias de pesquisa: revisão bibliográfica e entrevistas com projetistas de arquitetura e incorporador, com experiência na adoção de estrutura metálica e tecnologias pré-fabricadas de VVE em seus projetos. Como resultado, são propostas: diretrizes voltadas para o processo de projeto de arquitetura, incluindo recomendações para a organização da empresa de projeto que busca tomar decisões sobre tecnologias de VVE pautada em requisitos técnicos; diretrizes para identificar se o empreendimento está inserido em \"nichos estratégicos\" e se o \"ambiente\" para sua realização é favorável à adoção de tecnologias construtivas pré-fabricadas; e diretrizes para atendimento às exigências de desempenho, sustentabilidade, construtibilidade e legislação e normas técnicas a serem seguidas pelos projetistas de arquitetura. Conclui-se que, para responder às demandas de desempenho, sustentabilidade e construtibilidade, buscando adotar tecnologias construtivas pré-fabricadas de VVE, são necessários ao projetista de arquitetura: participação, de fato, na etapa de execução do edifício; estabelecimento de parcerias com agentes envolvidos no processo do empreendimento; manter-se atualizado quanto à legislação e normas técnicas (que têm revelado a tendência de não restringir ao uso de tecnologias construtivas tradicionais); especificar por desempenho as tecnologias de VVE adotadas em projeto; acompanhar a evolução das informações sobre o impacto ambiental gerado pelas tecnologias de VVE; e adotar os princípios de Coordenação Modular nos projetos. / The publication of NBR 15575: 2013 and the growing discussion about environment have brought even more emphasis on some specific demands, such as performance, sustainability and constructability in building projects. Considering that including these demands on design is a challenge, during the building construction is even more difficult, especially regarding the traditional process, which still dominates the production. On the other hand, the industrialization of construction, facilitated by usage of prefabricated technology, has potential to meet performance, sustainability and constructability requirements. The architect, an active professional since the beginning of design process, is the protagonist of technology selection and able to influence the choice for a more industrialized construction process. In order to discuss how an architect could improve his job when it comes to performance, sustainability and constructability demands, assuming an integrating agent role on design process, this research approaches the prefabricated technologies for external walls of steel structural buildings. The main purpose of the research is to propose guidelines for technology selection of external walls of steel structural buildings, aiming the architectural design development, considering the project goals and requirements related to performance, sustainability and constructability. Therefore, two research strategies have been chosen: literature review and interviews with architectural designers and developer, experienced in adopting steel structure and prefabricated technologies for external walls on their projects. As a result of this, it is proposed: guidelines oriented for the architectural design process, including recommendations to organize the design company which seeks for selecting technologies for external walls driven by technical requirements; guidelines to identify if the project is included on \"strategic segments\" and if the \"environment\" for its execution is advantageous to the adoption of prefabricated building technologies; and guidelines to meet performance, sustainability, constructability, legislation and technical standards requirements to be followed by architectural designers. In conclusion, to meet performance, sustainability and constructability demands, aiming the adoption of prefabricated building technologies for external walls, there are some specific needs for architectural designers: active participation on building execution phase; establishing partnerships with stakeholders during the development process; be up to date on the legislation and technical standards (which have been showing a trend to do not restrict the usage of traditional building technologies); to specify by performance the technologies for outside walls chosen on the project; follow the information development about environmental impact generated by outside wall technologies; and adopt the principles of Modular Coordination on the projects.