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Development of an integrated tool for numerical modelling of OWC-WECs in vertical breakwaters
No full textThis paper describes the advances on the research project DITOWEC – “Development of
an Integrated Tool for Numerical Modelling of Oscillating Water Column Wave Energy Converters
Integrated in Vertical Breakwaters", whose main objective is developing an innovative integrated tool for
numerical modelling of wave propagation from offshore to nearshore, of wave-structure interaction and
of the complex nonlinear hydrodynamic and aerodynamic phenomena that occur in an OWC-WEC. Its
development is supported by experimental data from physical model tests carried out at LNEC. The tool
will directly allow the simulation of the OWC-WEC of Pico, Azores (Portugal), at prototype scale, with
real bathymetry and offshore wave climate, eliminating any problem related to scale effects that may
occur in physical modelling. This application allows the comparison of numerical results and prototype
measurements for different incident wave conditions, given that this structure has been monitored since
2005. Methodologies of the DITOWEC project and accomplishments achieved so far are herein
described, with the focus on its more relevant results.186-195ppDHA/NP
Sustainable use of timber in construction - specification, detailing, maintenance and repair for extended life
No full textTimber is highly interesting from the point of view of sustainable construction and, besides most traditional uses it has received increasing attention in modern building industry. However, both the timber material and timber structures require particular attention, care and adequate strategies concern in materials specification, design, detailing, maintenance and repair for extended life.
Specific to timber as a raw material are its great variability, anisotropy, hygroscopic nature and the risk of biological degradation in adverse exposure conditions. Highly important or the performance and safety of timber structures are also the detailing of timber joints, dimensional variations and tensile stresses perpendicular to the wood grain, that often converge to cause malfunctions.146-155ppDE/NC
Caniçada dam complementary spillway. Design, hydraulic model and ongoing works
No full textIn order to meet the updated requirements of the Portuguese Dam Safety Legislation,
Caniçada dam (double-curvature arch dam, concluded in 1955 and located in the Cávado River) hydraulicoperational
safety assessment has been developed by EDP, including the review of the design flood and the
evaluation of safety devices capacity. Thereafter some corrective measures were implemented, including
the construction of a new complementary spillway. The paper summarizes the main features of the new
spillway design, developed by AQUALOGUS. The selected solution is a gate-controlled ogee crest,
followed by a 200 m long tunnel scoped in the slope of the left bank, designed for a discharge of 2062 m3/s.
The hydraulic performance of the designed structure was analysed by a study developed on a hydraulic
physical model, built at LNEC on a scale of 1/62. Results and conclusions that allowed improving the
design structure shapes are described, with particular emphasis on the use of the reduced physical model.
Some aspects of interesting and nowadays challenging ongoing works of this new spillway are also
presented.10ppDHA/NR
Introduction of the COST FP 1303 cooperative performance test
No full textCOST Action FP 1303 “Performance of bio-based building materials” successfully started in October 2013 and an ambitious program was set up for the four year programme. COST Actions provide an excellent opportunity for collaborative research, e.g. in the frame of Round Robin tests.
The idea of this respective test was to distribute a fairly simple test set up to as many places in Europe as possible in order to collect performance data reflecting the range of climatic exposure conditions. Furthermore we wanted to consider performance in its manifold meaning, i.e. optical, aesthetical, moisture and functional performance and durability. In contrast to traditional Round Robin tests aiming on comparative evaluation and validation of results from different test laboratories, this initiative aims on collecting performance data under climatically different exposure conditions. Therefore it was required to provide weather data from the respective test sites to allow establishing relationships between climate conditions and the following measured, which shall be evaluated regularly: decay, discolouration, development of mould and other staining fungi, corrosion, formation of cracks and moisture performance (if data logging device is included). Further details about the test and the first outcomes are presented in this paper.22pThe authors acknowledge support of COST Action FP1303, financial support from the Slovenian Research Agency within the framework of project L4-5517 and programme P4-0015 and support from Silvaprodukt d.o.o. in the frame of the Research voucher. Special thanks are given to all of the participants.DE/NC
Synergistic outdoor interactions between public spaces, users and locative technologies
No full textThis paper highlights the emerging concept of the CyberPark - the hybridized relationship between open public places and technologically mediated urban activity patterns. The concept questions whether urban space can keep binding people and their outdoor practices in new meaningful ways, but in fact, what is being asked is whether the relationship between ICT, open public spaces and urban activities can open up creative pathways for a multidisciplinary field. Projecting the transformative shifts not only in the way people choose, move and experience open spaces in cities but also from the impacts of the extensive outdoor use of digital media technologies such as wireless sensor networks, GNSS or cellular networks enabled by mobile devices, into the same coordinate space can transform the oppositional conditions in our understanding of the stroller/machine relationship. This paper introduces a synergistic user-centred methodology for deriving effective strategies for the appropriation and use of wireless urban spaces. To achieve this, it unfolds the first results from the CyberParks Project to help us locate its concept into the possibility of an enhanced form of open urban space that exceeds the “any space”.272-281pp.Trabalho realizado no âmbito do Projeto Action COST Ciberparks - TU 1306DM/NBP
Analysis of federated enterprise architecture models
No full textEnterprise architecture models support decision-making as they help organizations to understand, communicate and analyse how business processes are performed, the goals they achieve, the information they use, as well as the applications that realize the business, and the supporting technological infrastructure. The integrated analysis of these models is not straightforward because it cross-cuts different domains that are described using heterogeneous concepts. This paper explores the application of ontologies to analyse enterprise architecture models. Ontologies represent knowledge that can be analysed using computational inference. The contributions of this paper are (1) the specification of multiple enterprise architecture models as ontological schemas, (2) the integration of ontological schemas, and (3) the analysis of the integrated models. The solution artefact consists of a federated model specified as a set of ontological
schemas described in OWL-DL that integrates multiple enterprise models and assists their analysis using
computational inference. The paper demonstrates the application of the federated model to the ArchiMate
language as a means to assess the compliance of business requirements in a civil engineering scenario.1-14ppCD/NTIE
Estratégia de I&D&I 2013-2020 do Departamento de Estruturas do LNEC
No full textEste registo pertence ao Repositório Científico do LNECEste relatório apresenta a estratégia de I&D&I adotada pela Comissão Científica Departamental (CCD) do Departamento de Estruturas do LNEC (DE), em coerência com a estratégia de investigação e inovação (E2I) estabelecida pelo LNEC para o período 2013-2020 e respondendo ao Plano de Ação da E2I sobre o aprofundamento da E2I nas unidades departamentais do LNEC. Esta estratégia do DE enquadra nove linhas prioritárias de investigação, caracterizando-as em termos de conteúdos e de previsões de projetos, de participação de investigadores do DE, de outras unidades departamentais do LNEC e de parceiros externos.NÃO CONFIDENCIALDE/CHEFI
Reconstrução acústica da igreja São Miguel Arcanjo das Missões Jesuítas
No full textThe “Redução de São Miguel Arcanjo” is a part of the “Sete Povos das Missões” ruins, being a
strong evidence of the Jesuit missions and the European Baroque from the Iberian Peninsula,
also integrated into the southern Brazil indigenous culture. In this paper, the acoustic
reconstruction of “Igreja de São Miguel Arcanjo” was done. This church had the beginning of its
construction in 1735 and an interruption in 1745, due to the wars between Spanish and
Portuguese for territory control and possession. Within the frame of the study, a comparison was
done. For that, several possibilities for positioning the choir and changes in the parameters EDT,
D50, C80 and STI have been analyzed, considering the liturgical organization reported in
historical records.9 pDED/NAIC
A função da luz natural no edificado
No full textNo contexto do ano internacional da luz, o artigo descreve as principais funções da luz no edificado44-45pp.Artigo publicado na sequência de convite da revista no âmbito das comemorações do ano internacional da luzNº 147DED/NAICIIngeniun
Monitoring structure and regional-level displacements for Lisbon using multitemporal InSAR techniques
No full textThe city of Lisbon is the capital of Portugal and has been devastated by catastrophic events in the past, such as earthquakes and tsunamis. This study provides a regional analysis of displacements for the city and its neighbourhoods, between 2008 and 2010, through the application of mutitemporal InSAR techniques on Envisat ASAR images. Smaller areas with identified problems were subjected to a more refined processing. Besides, the behaviour of some key infrastructures, such as important buildings or railways, was carefully analysed in order to evaluate their safety. Subsidence was detected at the regional and small areas, in which the highest subsidence rates were verified on industrial parks or on landfills close to the river. Seasonal trends were found for the small areas, mainly related with structure thermal expansion or variations in underground water.7pDBB/NG