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- Independent Component Analysis for Extended Time Series in Climate DataPublication . Sebastião, Fernando; Oliveira, IreneVarious techniques of multivariate data analysis have been proposed to study time series, including the Multi-channel Singular Spectrum Analysis (MSSA). This technique is a Principal Component Analysis (PCA) of the extended matrix of initial lagged series, also called Extended Empirical Orthogonal Function (EEOF) Analysis in a climatological context. This work uses Independent Component Analysis (ICA) as an alternative to the MSSA method, when studying the extended time series matrix. Often, ICA is more appropriate than PCA to analyse time series, since the extraction of Independent Components (ICs) involves higher-order statistics whereas PCA only uses the second-order statistics to obtain the Principal Components (PCs), which are not correlated and are not necessarily independent. An example of time series for meteorological data and some comparative results between the techniques under study are given. Different methods of ordering ICs are also presented, including a new one, which may influence the quality of the reconstruction of the original data.
- A bibliometric study of John Dunning’s contribution to international business researchPublication . Ferreira, Manuel Portugal; Pinto, Cláudia Sofia Frias; Serra, Fernando Antonio Ribeiro; Santos, João CarvalhoThis article offers a review of John Dunning’s contribution to international business (IB) research, so as to assess the impact of Dunning and of the Eclectic paradigm on this discipline. The contribution of Dunning and of the Eclectic paradigm – usually referred to as OLI – are a core reference to current international business research, namely for studying location decisions, foreign investment, entry modes and internationalization, and for the multinational enterprise theory. First, we review the conceptual foundations of Dunning’s academic contribution. Second, methodologically, we carry out a bibliometric study of articles published in 14 respected academic business magazines over a period of 31 years, between 1980 and 2010. A sample of 697 published articles that refer to Dunning’s work supports the analysis of citations and co-citations matrixes and of relevant themes, allowing us to verify the influence of Dunning’s work on the international business and Management disciplines. This study allowed us to identify the network of connections between Dunning’s Eclectic paradigm and a variety of international business theories, concepts and authors, as well as with the main subjects studied in the discipline. We observed the connections to the transaction costs theory, resource-based view, industrial organization and evolutionary theory. This study also contributes to scholars’ better understanding of the development of the discipline and of the structure of knowledge within connections between theories and authors. Through their contributions, scholars such as John Dunning leave their imprint on the way in which disciplines and knowledge evolve. Dunning’s work, in the Eclectic paradigm, systematized three conditions that guide the internationalization of companies – and is now a reference for entrepreneurial activities, scholars and research.
- Una construcción teórico-prática del paisaje en el campo escultóricoPublication . Rama, Samuel José Travassos; Tatay, Amparo CarbonellEl presente trabajo de investigación intenta dar cuerpo a una posibilidad de articulación teórico-práctica del paisaje en el campo de lo escultórico. De esta forma, se ha pretendido construir un itinerario reflexivo en torno a una serie de cuestiones –enunciadas por nuestras palabras clave–, que fueron suscitadas por un conjunto de propuestas plásticas realizadas antes del inicio de este trabajo de investigación.
- A casa de S. Pedro na literatura, memória e cultura de Portugal e do MundoPublication . Nobre, CristinaQuais as várias etapas pelas quais a Casa de S. pedro, do poeta Afonso Lopes Vieira se foi transformando num lugar literário, guardando memórias de artistas, livros e objetos vários, até à fundação em 2005 da Casa-museu Afonso Lopes Vieira.
- Lugar literário: fios tecidos no inventário temáticoPublication . Nobre, CristinaVisou o estudo aprofundado do acervo da Casa-Museu, desde o espólio documental ao mobiliário, passando pelas pinturas, desenhos, gravuras, esculturas, têxteis, fotografias e diversos instrumentos científicos, metais, equipamentos e utensílios, chegando ao espólio de malacologia da casa, com especial enfoque para a varanda, entendida como lugar privilegiado da criação literária.
- O lugar da investigação participada de base comunitária na promoção da saúde mentalPublication . Gomes, José Carlos Rodrigues; Loureiro, Maria Isabel GuedesA saúde mental é imprescindível ao desenvolvimento social e económico das comunidades. Envolver as comunidades no desenho e desenvolvimento de planos locais de promoção da saúde mental é um importante desafio para garantir mais e melhor saúde mental a cada comunidade. De 2009 a 2012 desenvolveu-se um estudo de caso baseado nos pressupostos de uma investigação participada de base comunitária numa comunidade urbana da região metropolitana de Lisboa, com o objetivo de fundamentar o desenho de um plano local de promoção da saúde mental local. O resultado deste trabalho de parceria, que envolveu habitantes e organizações governamentais e não-governamentais da comunidade urbana, fundamentado na capacitação individual e comunitária da comunidade e dos seus membros, confirmou a necessidade de uma participação ativa e efetiva da comunidade no desenvolvimento de políticas locais de promoção da saúde e concluiu pela definição de 6 eixos estratégicos de intervenção pelo período temporal 2012/2015: uma escola com saúde mental; uma comunidade ativa e segura; uma comunidade solidária e inclusiva; uma comunidade atenta; uma organização económico-laboral promotora de saúde mental; uma senioridade mentalmente saudável.
- Swarm optimisation algorithms applied to large balanced communication networksPublication . Bernardino, Eugénia Moreira; Bernardino, Anabela Moreira; Sánchez-Pérez, Juan Manuel; Pulido, Juan Antonio Gómez; Rodríguez, Miguel A. VegaIn the last years, several combinatorial optimisation problems have arisen in the computer communications networking field. In many cases, for solving these problems it is necessary the use of metaheuristics. An important problem in communication networks is the Terminal Assignment Problem (TAP). Our goal is to minimise the link cost of large balanced communication networks. TAP is a NP-Hard problem. The intractability of this problem is the motivation for the pursuits of Swarm Intelligence (SI) algorithms that produce approximate, rather than exact, solutions. This paper makes a comparison among the effectiveness of three SI algorithms: Ant Colony Optimisation, Discrete Particle Swarm Optimisation and Artificial Bee Colony. We also compare the SI algorithms with several algorithms from literature. Simulation results verify the effectiveness of the proposed algorithms. The results show that SI algorithms provide good solutions in a better running time.
- Analysis of vehicle exhaust waste heat recovery potential using a Rankine cyclePublication . Domingues, António; Santos, Helder; Costa, MárioThis study evaluates the vehicle exhaust WHR (waste heat recovery) potential using a RC (Rankine cycle ). To this end, both a RC thermodynamic model and a heat exchanger model have been developed. Both models use as input, experimental data obtained from a vehicle tested on a chassis dynamometer. The thermodynamic analysis was performed for water, R123 and R245fa and revealed the advantage of using water as the working fluid in applications of thermal recovery from exhaust gases of vehicles equipped with a spark-ignition engine. Moreover, the heat exchanger effectiveness for the organic working fluids R123 and R245fa is higher than that for the water and, consequently, they can also be considered appropriate for use in vehicle WHR applications through RCs when the exhaust gas temperatures are relatively low. For an ideal heat exchanger, the simulations revealed increases in the internal combustion engine thermal and vehicle mechanical efficiencies of 1.4%-3.52% and 10.16%-15.95%, respectively, while for a shell and tube heat exchanger, the simulations showed an increase of 0.85%-1.2% in the thermal efficiency and an increase of 2.64%-6.96% in the mechanical efficiency for an evaporating pressure of 2 MPa. The results confirm the advantages of using the thermal energy contained in the vehicle exhaust gases through RCs. Furthermore, the present analysis demonstrates that improved evaporator designs and appropriate expander devices allowing for higher evaporating pressures are required to obtain the maximum WHR potential from vehicle RC systems.
- A state-of-the-art review on roughness quantification methods for concrete surfacesPublication . Santos, Pedro M. D.; Júlio, Eduardo N.B.S.Surface roughness plays an important role in the behavior of concrete-to-concrete interfaces. Methods like sand-blasting and hydrodemolition are usually adopted to improve the surface roughness of the concrete substrate. Before placing the new concrete layer it is common to verify the roughness level by visual inspection. However, this procedure can lead to inaccurate conclusions since it is influenced by the technician’s opinion and, therefore, it is subjective. Current design codes of concrete structures implicitly propose this type of assessment since there is not a specified method or device to verify the conditions of the substrate surface. To overcome the drawbacks of this qualitative methodology, a quantitative approach should be adopted instead. Thus, it is necessary to measure the surface roughness and, from this, to compute roughness parameters. This paper presents a review on roughness quantification methods that can be adopted for concrete surfaces.
- Perceptual images of Conimbriga using High Dynamic RangePublication . Gonçalves, Alexandrino; Moura, João Paulo; Magalhães, Luís; Chalmers, AlanIt is widely recognized that new technologies can play an important role in the interpretation of our cultural heritage legacy. This has become a powerful tool providing a better understanding of our past, and thereby, allowing us to attain a glimpse of the environments in which our ancestors lived. In this domain, the way we see such reconstructed environments is particularly important in order to establish an accurate interpretation of that historical setting. However, the desired visual accuracy in the representation of any archaeological scenario is strictly related to the technology used to visualize it. High Dynamic Range (HDR) technology encompasses the capacity to produce visual results similar to the visual acuity of the human eye, particularly in extreme lighting conditions, such as bright light or dim environments. In this paper we present an ancient flame light simulation method and a perceptual visual user study with HDR images of Roman mosaics and frescoes, illuminated by luminaries of that period, located in one of the most impressive monuments in the ruins of Conimbriga, Portugal. With this work we intend to demonstrate how the use of this particular low intensity Roman light, when compared to other modern illumination, affects the subjects’ perception of ancient artefacts and influences the scenario viewing pattern.