Modelo generalista de páginas Web para motores de pesquisa com interface 3D

Web tornou-se uma ferramenta indispensável para a sociedade moderna. A capacidade de aceder a enormes quantidades de informação, disponível em praticamente todo o mundo, é uma grande vantagem para as nossas vidas. No entanto, a quantidade avassaladora de informação disponível torna-se um problema, que é o de encontrar a informação que precisamos no meio de muita informação irrelevante. Para nos ajudar nesta tarefa, foram criados poderosos motores de pesquisa online, que esquadrinham a Web à procura dos melhores resultados, segundo os seus critérios, para os dados que precisamos. Actualmente, os motores de pesquisa em voga, usam um formato de apresentação de resultados simples, que consiste apenas numa caixa de texto para o utilizador inserir as palavras-chave sobre o tema que quer pesquisar e os resultados são dispostos sobre uma lista de hiperligações ordenada pela relevância que o motor atribui a cada resultado. Porém, existem outras formas de apresentar resultados. Uma das alternativas é apresentar os resultados sobre interfaces em 3 dimensões. É nestes tipos de sistemas que este trabalho vai incidir, os motores de pesquisa com interfaces em 3 dimensões. O problema é que as páginas Web não estão preparadas para serem consumidas por este tipo de motores de pesquisa. Para resolver este problema foi construído um modelo generalista para páginas Web, que consegue alimentar os requisitos das diversas variantes destes motores de pesquisa. Foi também desenvolvido um protótipo de instanciação automático, que recolhe as informações necessárias das páginas Web e preenche o modelo.

Projecto de pré-dimensionamento de uma ETAR em Luanda - Angola

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Hidráulica

Edifícios altos – problemas associados e análise estrutural de um caso prático

Com a presente dissertação pretende-se analisar alguns dos problemas associados aos edifícios altos, na fase de projeto, bem como compilar um conjunto de informações e conhecimentos científicos sobre a área abordada. São descritas algumas soluções de sistemas estruturais possíveis de idealizar para edifícios altos. Posteriormente, tendo por base um projeto de estruturas de um edifício com 25 pisos localizado em Luanda, capital de Angola, o objetivo consistiu em analisar estática e dinamicamente o seu comportamento quando solicitado fundamentalmente pelas ações do vento e dos sismos. A análise estrutural foi realizada com recurso a dois softwares de cálculo automático, nomeadamente, o Cypecad e o Robot Structural Analysis Professional e pelos métodos preconizados no Regulamento de Segurança e Ações para estruturas de edifícios e pontes e o Eurocódigo 8 – “Projeto de estruturas para resistência aos sismos”. Aborda-se a temática do faseamento construtivo, assunto que revela algumas limitações dos programas de cálculo utilizados, sendo descrito um método simplificado para prever os seus efeitos em termos de dimensionamento final. Os resultados obtidos permitiram avaliar o bom comportamento da estrutura no que respeita ao cumprimento dos estados limites últimos e de serviço. Conclui-se que o sistema estrutural adotado no modelo em estudo se encontra bem dimensionado relativamente ao colapso e à limitação de danos.

Towards the detection of deception in interactive multimedia environments

A classical application of biosignal analysis has been the psychophysiological detection of deception, also known as the polygraph test, which is currently a part of standard practices of law enforcement agencies and several other institutions worldwide. Although its validity is far from gathering consensus, the underlying psychophysiological principles are still an interesting add-on for more informal applications. In this paper we present an experimental off-the-person hardware setup, propose a set of feature extraction criteria and provide a comparison of two classification approaches, targeting the detection of deception in the context of a role-playing interactive multimedia environment. Our work is primarily targeted at recreational use in the context of a science exhibition, where the main goal is to present basic concepts related with knowledge discovery, biosignal analysis and psychophysiology in an educational way, using techniques that are simple enough to be understood by children of different ages. Nonetheless, this setting will also allow us to build a significant data corpus, annotated with ground-truth information, and collected with non-intrusive sensors, enabling more advanced research on the topic. Experimental results have shown interesting findings and provided useful guidelines for future work. Pattern Recognition

Multi-criteria design optimization study of solvent extraction in mixer–settler units

Solvent extraction is considered as a multi-criteria optimization problem, since several chemical species with similar extraction kinetic properties are frequently present in the aqueous phase and the selective extraction is not practicable. This optimization, applied to mixer–settler units, considers the best parameters and operating conditions, as well as the best structure or process flow-sheet. Global process optimization is performed for a specific flow-sheet and a comparison of Pareto curves for different flow-sheets is made. The positive weight sum approach linked to the sequential quadratic programming method is used to obtain the Pareto set. In all investigated structures, recovery increases with hold-up, residence time and agitation speed, while the purity has an opposite behaviour. For the same treatment capacity, counter-current arrangements are shown to promote recovery without significant impairment in purity. Recycling the aqueous phase is shown to be irrelevant, but organic recycling with as many stages as economically feasible clearly improves the design criteria and reduces the most efficient organic flow-rate.

Analysis and visualization of seismic data using mutual information

Seismic data is difficult to analyze and classical mathematical tools reveal strong limitations in exposing hidden relationships between earthquakes. In this paper, we study earthquake phenomena in the perspective of complex systems. Global seismic data, covering the period from 1962 up to 2011 is analyzed. The events, characterized by their magnitude, geographic location and time of occurrence, are divided into groups, either according to the Flinn-Engdahl (F-E) seismic regions of Earth or using a rectangular grid based in latitude and longitude coordinates. Two methods of analysis are considered and compared in this study. In a first method, the distributions of magnitudes are approximated by Gutenberg-Richter (G-R) distributions and the parameters used to reveal the relationships among regions. In the second method, the mutual information is calculated and adopted as a measure of similarity between regions. In both cases, using clustering analysis, visualization maps are generated, providing an intuitive and useful representation of the complex relationships that are present among seismic data. Such relationships might not be perceived on classical geographic maps. Therefore, the generated charts are a valid alternative to other visualization tools, for understanding the global behavior of earthquakes.

Influence of network effects on the diffusion of information systems: the case of open source

Doutoramento em Gestão

Need for, demand for, and use of European Union information

The discussion and analysis of the diverse outreach activities in this article provide guidance and suggestions for academic librarians who are interested in outreach and community engagement of any scale and nature. Cases are draw from a wide spectrum and are particularly strong in the setting of large academic libraries, special collections and programming for multicultural populations. The aim of this study is to present the results of research carried out regarding the needs, demand and consumption of European Union information by users in European Documentation Centres (EDC). A quantitative methodology was chosen based on a questionnaire with 24 items. This questionnaire was distributed within the EDC of Salamanca, Spain, and the EDC of Porto, Portugal, during specific time intervals between 2010 and 2011. We examined the level of EU information that EDC users possess, and identified the factors that facilitate or hinder access to EU information, the topics most demanded, and the types of documents consulted. Analysis was made of the use that the consumer of European information makes of databases and their behaviour during the consultation. Although the sample used was not very significant owing to its small size, it is a faithful reflection of the scarce visits made to EDCs. This study can be of use to managers of EDCs, providing them with better knowledge of the information needs and demands of their users. Ultimately this should lead to improvements in the services offered. The study lies within a frame of research scarcely addressed in specialized scholarly literature: European Union information.

James W. Carey as critical theorist of the information age

This paper suggests that the thought of the North-American critical theorist James W. Carey provides a relevant perspective on communication and technology. Having as background American social pragmatism and progressive thinkers of the beginning of the 20th century (as Dewey, Mead, Cooley, and Park), Carey built a perspective that brought together the political economy of Harold A. Innis, the social criticism of David Riesman and Charles W. Mills and incorporated Marxist topics such as commodification and sociocultural domination. The main goal of this paper is to explore the connection established by Carey between modern technological communication and what he called the “transmissive model”, a model which not only reduces the symbolic process of communication to instrumentalization and to information delivery, but also politically converges with capitalism as well as power, control and expansionist goals. Conceiving communication as a process that creates symbolic and cultural systems, in which and through which social life takes place, Carey gives equal emphasis to the incorporation processes of communication.If symbolic forms and culture are ways of conditioning action, they are also influenced by technological and economic materializations of symbolic systems, and by other conditioning structures. In Carey’s view, communication is never a disembodied force; rather, it is a set of practices in which co-exist conceptions, techniques and social relations. These practices configure reality or, alternatively, can refute, transform and celebrate it. Exhibiting sensitiveness favourable to the historical understanding of communication, media and information technologies, one of the issues Carey explored most was the history of the telegraph as an harbinger of the Internet, of its problems and contradictions. For Carey, Internet was seen as the contemporary heir of the communications revolution triggered by the prototype of transmission technologies, namely the telegraph in the 19th century. In the telegraph Carey saw the prototype of many subsequent commercial empires based on science and technology, a pioneer model for complex business management; an example of conflict of interest for the control over patents; an inducer of changes both in language and in structures of knowledge; and a promoter of a futurist and utopian thought of information technologies. After a brief approach to Carey’s communication theory, this paper focuses on his seminal essay "Technology and ideology. The case of the telegraph", bearing in mind the prospect of the communication revolution introduced by Internet. We maintain that this essay has seminal relevance for critically studying the information society. Our reading of it highlights the reach, as well as the problems, of an approach which conceives the innovation of the telegraph as a metaphor for all innovations, announcing the modern stage of history and determining to this day the major lines of development in modern communication systems.

Projecto de uma passagem superior à autoestrada 10

Trabalho de Projecto para obtenção do grau de Mestre em Engenharia Civil

Criação de valor - O Cash Value Added como métrica de avaliação da Performance empresarial

Mestrado em Contabilidade e Gestão das Instituições Financeiras

Níveis de referência em diagnóstico em tomografia computorizada para planeamento em radioterapia

Mestrado em Radiações Aplicadas às Tecnologias da Saúde- Ramo de especialização: Terapia com Radiações

Risk criteria in occupational environments: critical overview and discussion

The current work can be seen as a starting point for the discussion of the problematic on risk acceptance criteria in occupational environments. Some obstacles to the quantitative acceptance criteria formulation and use were analyzed. A look to the long tradition of major hazards accidents was also performed. This work shows that organizations can have several difficulties in acceptance criteria formulation and that the use of pre-defined acceptance criteria in risk assessment methodologies can be inadequate in some cases. It is urgent to define guidelines that can help organizations in the formulation of risk acceptance criteria for occupational environments.

Water quality in lakes and reservoirs in China

Dissertation elaborated for the partial fulfilment of the requirements of the Master Degree in Civil Engineering in the Speciality Area of Hydarulics

Use of negative information in positioning and tracking algorithms

To avoid additional hardware deployment, indoor localization systems have to be designed in such a way that they rely on existing infrastructure only. Besides the processing of measurements between nodes, localization procedure can include the information of all available environment information. In order to enhance the performance of Wi-Fi based localization systems, the innovative solution presented in this paper considers also the negative information. An indoor tracking method inspired by Kalman filtering is also proposed.