Estimation of 3D shapes using active surface models

This paper addresses the estimation of surfaces from a set of 3D points using the unified framework described in [1]. This framework proposes the use of competitive learning for curve estimation, i.e., a set of points is defined on a deformable curve and they all compete to represent the available data. This paper extends the use of the unified framework to surface estimation. It o shown that competitive learning performes better than snakes, improving the model performance in the presence of concavities and allowing to desciminate close surfaces. The proposed model is evaluated in this paper using syntheticdata and medical images (MRI and ultrasound images).

Virtual Communities of Practice: Design and Development of Support Platforms and Participation Fostering

Mestrado em Engenharia Informática - Área de Especialização em Sistemas Gráficos e Multimédia

Estratégia de dinamização da comunicação interna num operador de cabo em ambiente virtual

Relatório de Estágio apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Novos Media e Práticas Web.

Interface multitoque para exploração de colecção de arte

Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia Informática

Estudo de avaliação e quantificação de parâmetros associados à rigidez em patologias do tecido hepático com recurso à aplicação Virtual Touch

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Biomédica

Gestão de produto PREMFIRE – sistema de informação geográfica 3D para apoio ao combate a incêndios.

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação Geográfica.

Realidade Imersiva Aplicada a Espaços Culturais

Informação é o conceito genérico de tudo que possa representar, conhecimento ou comunicação. Trata-se de conhecimento registado de forma impressa ou digital, oral ou audiovisual, mas ainda pode ser registada em suporte físico. Desde o início da civilização que o Ser Humano tenta criar novas formas de transmitir informação, antes da invenção da forma escrita era utilizado o método do desenho para descrever a realidade, este método ao longo do tempo foi evoluindo, ganhando mais qualidade, pormenor e suportes mais evoluídos. Mas sempre com a mesma intenção, a de conseguir transmitir de forma mais direta e percetível informação a qualquer individuo. Dado isto, o Ser Humano sempre produziu arte e a foi preservando para mostrar aos vindouros. Neste processo, os museus em conjunto com espaços culturais e artísticos, foram assumindo um papel de relevo na sociedade. Mas inicialmente o objetivo principal dos museus era o de preservar e expor artefactos históricos e culturais. A grande evolução tecnológica dos últimos anos veio dotar o Ser Humano com formas de aceder à informação tão simples e diversificadas, que no passado eram completamente impensáveis e certamente que no futuro irão ser descobertas ainda mais formas de registar e propagar a informação. Assim o presente trabalho descreve a investigação realizada, através de uma recolha de bibliografia, levantamento do estado-da-arte, que pretende descobrir se a construção de visitas virtuais imersivas é uma boa forma para mostrar um espaço cultural ao público, que está cada vez mais exigente e disperso geograficamente. Além do levantamento são estudados alguns exemplos de visitas virtuais existentes, de modo a detetar boas praticas e formas mais usuais para a criação de uma visita. Finalmente foi descrito todo o processo desde a recolha de informação até à própria implementação, construção de um protótipo para apresentar ao utilizador o espaço de uma fundação, a do escultor José Rodrigues. Este protótipo tem por objetivo mostrar ao utilizador a fundação o mais aproximado do real possível.

Living and growing within a museum: re-creating video art for conservation

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Conservação e Restauro

Profissões : sinergias entre o video interactivo e o 3D estereoscópico

Trabalho de Projecto apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Novos Media e Práticas Web

O serviço de referência - do tradicional ao virtual: o caso da Biblioteca do tribunal de Contas

Relatório de Estágio apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ciências da Informação e da Documentação

Uranium glass in museum collections

Journal of Cultural Heritage, nº 9 (2008), p. 64-68

Virtual Power Player Using Demand Response to Deal with Unexpected Low Wind Power Generation

Demand response is assumed as an essential resource to fully achieve the smart grids operating benefits, namely in the context of competitive markets and of the increasing use of renewable-based energy sources. Some advantages of Demand Response (DR) programs and of smart grids can only be achieved through the implementation of Real Time Pricing (RTP). The integration of the expected increasing amounts of distributed energy resources, as well as new players, requires new approaches for the changing operation of power systems. The methodology proposed in this paper aims the minimization of the operation costs in a distribution network operated by a virtual power player that manages the available energy resources focusing on hour ahead re-scheduling. When facing lower wind power generation than expected from day ahead forecast, demand response is used in order to minimize the impacts of such wind availability change. In this way, consumers actively participate in regulation up and spinning reserve ancillary services through demand response programs. Real time pricing is also applied. The proposed model is especially useful when actual and day ahead wind forecast differ significantly. Its application is illustrated in this paper implementing the characteristics of a real resources conditions scenario in a 33 bus distribution network with 32 consumers and 66 distributed generators.

Short-term Wind Forecasting to Support Virtual Power Player Operation

This paper proposes a wind speed forecasting model that contributes to the development and implementation of adequate methodologies for Energy Resource Man-agement in a distribution power network, with intensive use of wind based power generation. The proposed fore-casting methodology aims to support the operation in the scope of the intraday resources scheduling model, name-ly with a time horizon of 10 minutes. A case study using a real database from the meteoro-logical station installed in the GECAD renewable energy lab was used. A new wind speed forecasting model has been implemented and it estimated accuracy was evalu-ated and compared with a previous developed forecast-ing model. Using as input attributes the information of the wind speed concerning the previous 3 hours enables to obtain results with high accuracy for the wind short-term forecasting.

Maximizing the Social Welfare of Virtual Power Players Operation in Case of Excessive Wind Power

The integration of growing amounts of distributed generation in power systems, namely at distribution networks level, has been fostered by energy policies in several countries around the world, including in Europe. This intensive integration of distributed, non-dispatchable, and natural sources based generation (including wind power) has caused several changes in the operation and planning of power systems and of electricity markets. Sometimes the available non-dispatchable generation is higher than the demand. This generation must be used; otherwise it is wasted if not stored or used to supply additional demand. New policies and market rules, as well as new players, are needed in order to competitively integrate all the resources. The methodology proposed in this paper aims at the maximization of the social welfare in a distribution network operated by a virtual power player that aggregates and manages the available energy resources. When facing a situation of excessive non-dispatchable generation, including wind power, real time pricing is applied in order to induce the increase of consumption so that wind curtailment is minimized. This method is especially useful when actual and day-ahead resources forecast differ significantly. The distribution network characteristics and concerns are addressed by including the network constraints in the optimization model. The proposed methodology has been implemented in GAMS optimization tool and its application is illustrated in this paper using a real 937-bus distribution network with 20.310 consumers and 548 distributed generators, some of them non-dispatchable and with must take contracts. The implemented scenario corresponds to a real day in Portuguese power system.

Intelligent Remuneration and Tariffs for Virtual Power Players

Power systems have been through deep changes in recent years, namely due to the operation of competitive electricity markets in the scope the increasingly intensive use of renewable energy sources and distributed generation. This requires new business models able to cope with the new opportunities that have emerged. Virtual Power Players (VPPs) are a new type of player that allows aggregating a diversity of players (Distributed Generation (DG), Storage Agents (SA), Electrical Vehicles (V2G) and consumers) to facilitate their participation in the electricity markets and to provide a set of new services promoting generation and consumption efficiency, while improving players’ benefits. A major task of VPPs is the remuneration of generation and services (maintenance, market operation costs and energy reserves), as well as charging energy consumption. This paper proposes a model to implement fair and strategic remuneration and tariff methodologies, able to allow efficient VPP operation and VPP goals accomplishment in the scope of electricity markets.