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- A experiência industrial de Afonso Lopes VieiraPublication . Nobre, CristinaHá indícios de que, por volta de 1914, Afonso Lopes Vieira e um primo tenham feito parte de um grupo de pessoas com vontade de estabelecer uma nova fábrica de vidros, dirigida por António de Magalhães Júnior. A I Guerra não deve ter facilitado as coisas, mas tudo parece indicar que em 1917 a fábrica produzia alguma coisa.
- The mediator role of leadership in the relationship between knowledge management and the relationship between employeesPublication . Ferreira, Vítor; Santo, Lídia Espírito; Santo, Pedro EspíritoAccording to Nonaka, companies must innovate through knowledge. Nevertheless, knowledge acquisition, application and sharing often require a reorganization of the company as well as all the people who constitute it. There is some empiric proof that good employee relations in developments that give rise to high levels of job satisfaction positively influences organisational performance. Thus, it is of utmost importance to study the influence of knowledge management practices in employee relations and on the company work environment. At the same time, leadership also may play an important role by enabling knowledge transfer and assuring a good human resource quality, thus fostering competitiveness. This study tries to identify the influence of knowledge (acquisition and application) and its sharing in “human resource quality relations” in SMEs. Thus, applying a questionnaire to 187 companies considered “SMEs leaders” in Portugal, this study, through a structural equation model, shows that knowledge management has a positive effect on Employee Relations Quality and Leadership has a mediating and positive effect in this relation. This paper, through a significant sample of SMEs, allows has to study the impact of KM practices in the quality of employee relations. This paper further investigates the relation between knowledge sharing and the ability to create a high level of quality of human resources.
- Structural conservation and vernacular constructionPublication . Lourenço, P.B.; Varum, H.; Vasconcelos, G.; Rodrigues, H.Modern societies understand built cultural heritage, including vernacular construction, as a landmark of culture and diversity, which needs to be protected and brought to the next generations in suitable condition. Still, a large part of this heritage is affected by structural problems that menace the safety of buildings and people. In the case of vernacular construction, deterioration due to abandonment is often present, making the phenomena of urbanization one of the most important menaces to this built heritage. The developments in the areas of inspection, non-destructive testing, monitoring and structural analysis of historical constructions, together with recent guidelines for reuse and conservation, allow for safer, economical and adequate remedial measures, as discussed in this paper.
- Different Design Criteria for District Metered Areas in Water Distribution NetworksPublication . Gomes, Ricardo; Sousa, Joaquim; Muranho, João; Marques, Alfeu SáIn this paper the influence of several factors to establish a suitable DMA design is considered using an adaptation of the methodology previously developed by Gomes [1]. This methodology is based on graph theory concepts (Floyd-Warshall algorithm) and some user-defined criteria to establish the number and size of DMAs and uses a Simulated Annealing algorithm to identify the most appropriate number and location of metering stations, boundary valves and network reinforcement/replacement needs along the project plan. Different design criteria are applied to a case study and the results obtained by the methodology are used to draw some conclusions. © 2015 The Authors.
- Systematic liquidity: commonality and inter-temporal variation in the Portuguese stock marketPublication . Miralles-Marcelo, José Luis; Miralles Quirós, María Del Mar; Oliveira, CéliaThe aim of this paper is to study systematic liquidity at the Euronext Lisbon Stock Exchange. The motivation for this research is provided by the growing interest in financial literature about stock liquidity and the implications of commonality in liquidity for asset pricing since it could represent a source of non-diversifiable risk. Namely, it is analysed whether there exist common factors that drive the variation in individual stock liquidity and the causes of the inter-temporal variation of aggregate liquidity. Monthly data for the period between January 1988 and December 2011 is used to compute some of the most used proxies for liquidity: bid-ask spreads, turnover rate, trading volume, proportion of zero returns and the illiquidity ratio. Following Chordia et al. (2000) methodology, some evidence of commonality in liquidity is found in the Portuguese stock market when the proportion of zero returns is used as a measure of liquidity. In relation to the factors that drive the inter-temporal variation of the Portuguese stock market liquidity, the results obtained within a VAR framework suggest that changes in real economy activity, monetary policy (proxied by changes in monetary aggregate M1) and stock market returns play an important role as determinants of commonality in liquidity.
- Self Similarity of Sousa Ramos’s Trees and Mira’s Boxes Within the BoxesPublication . Baptista, Diogo; Fournier-Prunaret, Daniele; Grácio, Clara; Fernandes, SaraThis work consists on the theory of embedded boxes structure [7], from the point of view of the theory of symbolic dynamics [6], tree structure Ramos [8], [9], [10] and star product [1] . This merger allowed the outcome-applications defined on the real line and a better understanding of the structure of the bifurcation, which allows us to characterize and understand the dynamics behind an application within the chaotic dynamical systems.
- Collaborative Vehicle Self-Localization Using Multi-GNSS Receivers and V2V/V2I CommunicationsPublication . Conde Bento, Luis; Chelim, Rafael; Nunes, UrbanoThis paper presents a collaborative self-localization approach using a multi-GNSS receiver setup and V2V/V2I communications. The purpose is to develop a low-cost alternative (equipment and installation), without compromising the process of localization estimation. The proposed method uses two GPS-receivers installed on the vehicle, disposed longitudinally on the cover (to maximize the distance among receivers) in order to estimate the Yaw and Pitch angles. To estimate the Roll angle, the proposed approach uses information from a receiver on the road infrastructure or on a nearby vehicle using V2V and/or V2I communication (compliant with 802.11p standard). Experimental results revealed that the performance on both absolute positioning and Pitch angle estimation is very high. The method is accurate in Yaw angle estimation enabling acceptable results in heading computation. Therefore the use of this algorithm in risk assessment on crossroads approaching scenarios, is achievable with an affordable setup. The Roll angle estimation can reach satisfactory results if there is a third receiver in the vicinity and in a non-collinear position with respect to the installed onboard receivers.
- Augmented Reality and 3D Technologies: Mapping Case Studies in EducationPublication . Cardoso, Teresa; Coimbra, Teresa; Mateus, ArturLearning anywhere, anytime is becoming ever more a daily routine, due to the increasing and recent growth of information and communication technologies. In the last 5 years, their key characteristic and specifically in the use of mobile equipment and software have been their portability, mobility, and network access. The technological development, including software applications available for the implementation of three-dimensional contents, has been following this trend. Hence, it is important to know whether and how these threedimensional contents are being integrated in educational situations, namely, regarding augmented reality and mobile learning. Thus, a synthesis of Portuguese and international research works and case studies on the use of threedimensional augmented reality is chronologically presented along with the evolution of information and communication technologies. The main goal of this knowledge mapping is to contribute to the state of the art in threedimensional augmented reality technologies in education. In addition, it is aimed at framing the creation and implementation of three-dimensional content in higher education, specifically in the field of mathematics. © Springer-Verlag Berlin Heidelberg 2015.
- A real-time platform for collaborative research on Visible Light CommunicationPublication . Ribeiro, Carlos; Figueiredo, Mónica; Alves, Luis NeroThis paper reports the implementation and performance results of a real-time Visible Light Communication platform. The platform uses a high-level software abstraction architecture where the algorithms are developed and tested in MATLAB, using a modular architecture. With this modular approach it is very easy to add/remove blocks, making it amenable to collaboration with other groups with interest in this field, offering a real-time test bed to evaluate the performance of different modules, algorithms and optical front-ends, which is currently not available. The physical layer is based on DCO-OFDM and is implemented in a Xilinx Virtex-6 FPGA. We explore the optical front-end out-of-band bandwidth to transmit, showing the usefulness of adopting OFDM-based modulations schemes for VLC. Our system transmits at 2m over an indoor free space channel with 12MHz bandwidth, with more than 23dB gain difference, using QPSK, thus achieving 24Mbit/s with a BER smaller than the usual 3.8×10-3 limit.
- Persistence of measles antibodies, following changes in the recommended age for the second dose of MMR-vaccine in PortugalPublication . Gonçalves, Guilherme; Frade, João; Nunes, Carla; Mesquita, João Rodrigo; Nascimento, Maria São JoséIn populations vaccinated with two doses of combined measles–mumps–rubella vaccine (MMR), the serum levels of antibodies against measles depend on the vaccination schedule, time elapsed from the last dose and the area-specific epidemiological situation. Variables measuring “schedule” are age at first and second doses of MMR and intervals derived from that. Changes in vaccination schedules have been made in Portugal. The specific objectives of this study were to measure the association between those potential determinants and the concentration of measles-specific IgG antibodies, after the second dose of MMR. Convenience samples of three Portuguese birth cohorts were selected for this study (41, 66 and 60 born, respectively, in 2001–2003, 1990–1993 and 1994–1995). Geometric mean concentrations (GMC) for measles IgG were, respectively, 934, 251 and 144 mIU/ml; p < 0.001). Anti-measles-IgG serum concentration decreased with time since last vaccination (waning immunity) and was not influenced by any other component of vaccination schedule, namely age at vaccination with the second dose of MMR. Waning levels of measles antibodies have been observed elsewhere but not as fast as it was observed in Portuguese birth cohorts in this study. Changes in the vaccination schedules might have to be considered in the future.
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