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  • Database Marketing Process Supported by Ontologies
    Publication . Mota Pinto, Filipe; Marques, Alzira; Santos, Manuel Filipe
    The dramatic explosion of data and the growing number of different data sources are exposing researchers to a new challenge - how to acquire, maintain, and share knowledge from large databases in the context of rapidly applied and evolving research. This paper describes research on an ontological approach for leveraging the semantic content of ontologies to improve knowledge discovery in databases. We analyze how ontologies and knowledge discovery process may interoperate and present our efforts to bridge the two fields, knowledge discovery in databases and ontology learning for successful database usage projects.
  • Hybrid model for the energy efficiency of building services
    Publication . Galvão, João; Leitão, Sérgio; Malheiro, Salvador; Gaio, Tiago
    Energy is used in multiple activities and represents a fundamental good for the planet and well being of populations. From this stems a steady increase in energy consumption worldwide through the last decade, and it is well known that growing population usually accelerates its consumption.The primary energy consumed on the planet currently has origin in fossil fuels, once responsible for GHG (greenhouse gas) emission source, contributing to the global warming and climate change.In this context to meeting the commitments of the Kyoto Protocol and European standards, it is urgent that there is an increasing integration of all forms of renewable energy, in industrial and economic areas.Consequently, there should be an adaptation to environmental factors and sustainability of the processes of energy production and consumptions, associated with measures that encourage energy efficiency and educate people to the good energy practices, reducing waste also increasing the quality of life of humanity. © 2012 by Nova Science Publishers, Inc. All rights reserved.
  • Procedural Virtual Worlds
    Publication . Rodrigues, Nuno; Magalhães, Luís; Moura, João Paulo; Chalmers, Alan; Santos, Filipe; Morgado, Leonel
    With the increasing demand for more complex and larger models in different fields, such as the design of virtual worlds, video games, and computer animated movies, the need to generate them automatically has become more necessary than ever. Manual tools are no longer sufficient to match this rising need, and the impact that automatic tools may have within these fields is essential and may lead to an adoption of virtual worlds in a growing number of applications. Indeed, it is possible to eliminate most of the effort associated with the creation of such environments, by providing tools that may generate “massive” 3D content automatically. In consequence these tools may lead to an exponential growth of virtual environments and represent an important turn into the design of realistic virtual cities, which may have a huge impact on virtual world users. This chapter discusses the very complex issue of where and when procedural modelling may be used and presents some solutions and methods that have been successfully used in the aforementioned fields of application.
  • A Parallel Niched Pareto Evolutionary Algorithm for Multiple Sequence Alignment
    Publication . Silva, Fernando José Mateus da; Sánchez Pérez, Juan Manuel; Gómez Pulido, Juan Antonio; Vega Rodríguez, Miguel A.
    Multiple sequence alignment is one of the most common tasks in Bioinformatics. However, there are not biologically accurate methods for performing sequence alignment. Genetic Algorithms are adaptive search methods which perform well in large and complex spaces, such as the ones present when aligning a set of sequences. Parallel Genetic Algorithms, not only increase the speed up of the search, but also improve its efficiency, presenting results that are better than those provided by the sum of several sequential Genetic Algorithms. Although these methods are often used to optimize a single objective, they can also be used in multidimensional domains, finding all possible tradeoffs among multiple conflicting objectives. Parallel AlineaGA is an evolutionary algorithm which makes use of a Parallel Genetic Algorithm for performing multiple sequence alignment. We present a multiple objective approach of Parallel AlineaGA that uses a Parallel Niched Pareto Genetic Algorithm. We compare the performance of both versions using eight BAliBASE datasets. We also measure up the quality of the obtained solutions with the ones achieved by T-Coffee and ClustalW2, allowing us to observe that our algorithm reaches for better solutions in the majority of the datasets.
  • Chapter 8: Structure Development in Electrospun Fibres
    Publication . Mitchell, Geoffrey R.; Mohan, Saeed D.; Davis, Fred J.; Ahn, Kyung-Hwa; Al-Azab, Mohamed; El Hadi, Ahmed; Elliott, Delyth; Kariduraganavar, Mahadevappa Y.; Nagarajan, Anitha; Nazhipkyzy, Meruyert; Geoffrey R Mitchell
    Electrospinning is a process which transforms polymer solutions in to solid fibres in ∼25 ms. In the case of an amorphous polymer, the resultant molecular organisation may not be so different from that of the solution. However, polymers are rich in different types of ordering processes and these may be encountered during electrospinning. In many areas of polymer processing, the processing procedures can have a significant impact on the structure and hence properties of the final product as the selection of the chemical configuration
  • Dynamics and Biological Thresholds
    Publication . Burroughs, N. J.; Ferreira, M.; Martins, J.; Oliveira, B. M. P. M.; Pinto, Alberto A.; Stollenwerk, N.
    Our main interest is to study the relevant biological thresholds that appear in epidemic and immunological dynamical models. We compute the thresholds, of the SIRI epidemic models, that determine the appearance of an epidemic disease. We compute the thresholds, of a Tregs immunological model, that determine the appearance of an immune response.
  • Chapter 13. Future Perspectives on Electrospinning
    Publication . Mitchell, Geoffrey R.; Sperrin, Malcolm
    Although the origins of electrospinning date back over 100 years, it is intense activity in the last 21 years which has led to considerable improvements in our knowledge of electrospinning and the broad-ranging opportunities for commercial application. The recent development of melt electrospinning provides a new additive manufacturing tool, providing routes to structures from nanometres to millimetres. Here, we consider where this rollercoaster of a topic is heading and its future prospects.
  • Seismic behaviour analysis and retrofitting of a row building
    Publication . Barros, R.S.; Costa, A.; Varum, H.; Rodrigues, H.; Lourenço, P.B.; Vasconcelos, G.
    Rammed earth is one of the oldest building materials in the world, and it is present in Portugal with a particular focus in the South of the country. The mechanical properties and the structural behaviour of rammed earth constructions have been the subject of study of many researchers in the recent years. This study is part of a broader research on vernacular seismic culture in Portugal. Numerical analyses were carried out to assess the influence of different retrofitting solutions in the behaviour and seismic performance of a rammed earth building, representative of the vernacular heritage of Alentejo region. Understating the structural fragilities of this type of constructions allowed determining the most appropriate retrofitting solutions.
  • Smart Remote Control Design for Seniors
    Publication . Pereira, António; Silva, Fernando; Ribeiro, José; Marcelino, Isabel; Barroso, João
    Technology is present in almost all aspects of our modern lives, and technological advances have been more and more prevalent. One would expect this to facilitate everybody’s life, rendering common tasks more practical and easier to perform, but that is often not the case - at least not for the elderly. Older people have significant difficulties in using technological equipment due to the visual, physical, cognitive and hearing limitations associated with the natural aging process; these aspects must be taken into account if the intention is that of integrating technology in the lives of the elderly. In order to improve the quality of life of the elderly, as well as to prevent their social isolation, a mobile device application was developed to act as an intelligent remote control. This mobile application deals with data from two different platforms that were previously developed for improving the quality of life of the senior population: HbbTV and +Social. The features built into this virtual remote control include the integration with the +Social platform, as well as a speech recognition mechanism, and the possibility of making and receiving video calls with an integrated contacts list. A comprehensive study was carried out, focusing on recommendations and rules for graphical interfaces for the elderly, so as to allow equipping the application with adequate usability standards. The most relevant result was the definition of a list of guidelines used to steer the development of the interface. An investigation of mechanisms and technologies for enabling the implementation of the required functionalities was also carried out in order to define methodologies for freeing the user from the need of possessing any level of computer literacy. A series of usability tests was also performed to validate the viability of the remote control application. These tests allowed assessing the quality of the application, especially concerning the Graphical User Interface, as well as to receive feedback from potential end users. Based on the data collected during the test phase we conclude that this product is useful and that it responds to a current need.
  • An integrated quantitative framework for supporting product design in the mold sector
    Publication . Ferreira, Irene; Cabral, J. A.; Saraiva, P.; Oliveira, M. C.
    The injection mold is a high precision tool responsible for the production of most plastic parts used everywhere. Its design is considered critically important for the quality of the product and efficient processing, as well as determinant for the economics of the entire injection molding process. However, typically, no formal engineering analysis is carried out during the mold design stage. In fact, traditionally, designers rely on their skills and intuition, following a set of general guidelines. This does not ensure that the final mold design is acceptable or the best option. At the same time, mold makers are now highly pressured to shorten both leading times and cost, as well as to accomplish higher levels of mold performance. For these reasons, it is imperative to adopt new methods and tools that allow for faster and higher integrated mold design. To that end, a new global approach, based on the integration of well-known quantitative techniques, such as Design for Six Sigma (DFSS), Structural Equation Modeling (SEM), Axiomatic Design (AD) and Multidisciplinary Design Optimization (MDO) is presented. Although some of these methods have been largely explored, individually or in combination with other methodologies, a quantitative integration of all aspects of design, in such a way that the whole process becomes logical and comprehensible, has not yet been considered. To that end, the DFSS methodology, through its IDOV roadmap, was adopted. It is based on the ICOV Yang and El-Haik proposal, establishing four stages for the design process: Identify, which aims to define customers' requirements/expectations; Design, where the creation of a product concept, and its system-level design, is performed; Optimization, in which all the detailed design, through product optimization, is handled; and finally, Validation, where all product design decisions are validated, in order to verify if the new designed entity indeed meets customer and other requirements. As a result, this approach tackles the design of an injection mold in a global and quantitative approach, starting with a full understanding of customer requirements and converting them into optimal mold solutions. In order to validate it, an integrated platform was developed, where all different analysis modules were inserted and optimized through an overseeing code system. The results attained highlight the great potential of the proposed framework to achieve mold design improvements, with consequent reduction of rework and time savings for the entire mold design process.