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Calibration of mirror position and extrinsic parameters in axial non-central catadioptric systems
Publication . Perdigoto, Luís; Araujo, Helder
We propose a novel calibration method for catadioptric systems made up of an axial symmetrical mirror and a pinhole camera with its optical center located at the mirror axis. The calibration estimates the relative camera/mirror position and the extrinsic rotation and translation w.r.t. the world frame. The procedure requires a single image of a (possibly planar) calibration object. We show how most of the calibration parameters can be estimated using linear methods (Direct-Linear-Transformation algorithm) and cross-ratio. Two remaining parameters are obtained by using non-linear optimization. We present experimental results on simulated and real images.
A cloud‐based integration platform for enterprise application integration: A Model‐Driven Engineering approach
Publication . Frantz, Rafael Z.; Corchuelo, Rafael; Basto‐Fernandes, Vitor; Rosa-Sequeira, Fernando; Roos‐Frantz, Fabricia; Arjona, José L.
This article addresses major information systems integration problems, approaches, technologies, and tools within the context of Model-Driven Software Engineering. The Guaraná integration platform is introduced as an innovative platform amongst state-of-the-art technologies available for enterprises to design and implement integration solutions. In this article, we present its domain-specific modeling language and its industrial cloud-based web development platform, which supports the design and implementation of integration solutions. A real-world case study is described and analyzed; then, we delve into its design and implementation, to finally disclose ten measures that empirically help estimating the amount of effort involved in the development of integration solutions.
Multi-material NiTi-PEEK hybrid cellular structures by Selective Laser Melting and Hot Pressing: Tribological characterization
Publication . Costa, M. M.; Bartolomeu, F.; Palmeiro, J.; Guimarães, B.; Alves, N.; Miranda, G.; Silva, F. S.
In this study, a multi-material NiTi-PEEK cellular structured solution was designed, produced and characterized targeting orthopedic applications. For that purpose, Selective Laser Melting (SLM) technique was used to produce NiTi cellular structures with different open-cell sizes and wall thicknesses. Hot Pressing (HP) technique was used to introduce PEEK in the open-cells of NiTi structures to obtain multi-material components. Morphological characterization showed that the selected SLM processing parameters were suited to achieve high-quality parts without significant defects. Tribological characterization proved an enhanced wear resistance to the multi-material specimens when compared with the mono-material NiTi structures. These multi-material structures are a promising solution for providing a customized stiffness and superior wear resistance to NiTi structures to be integrated in innovative orthopedic designs.
12. Conclusion
Publication . Gkonou, Christina; Dewaele, Jean-Marc; Daubney, Mark; Gkonou; Daubney; Dewaele
In this final chapter we would like to bring together the main themes emerging from all contributions to this volume in terms of recent developments in theorising about language anxiety, empirically investigating it and suggesting practical ideas for addressing it. As many authors in this anthology have acknowledged, research into language anxiety is not new to the field of second language acquisition (SLA) (cf. Horwitz, 2010). In this sense, the present volume could be viewed as a compilation of new insights into language anxiety which, taken together, are indicative of a need to broaden the agenda on three fronts: theory, research and practice. In what follows we discuss what we feel are the most salient themes with regard to language anxiety and these three aspects.
Computational technologies in tissue engineering
Publication . Almeida, H. A.; Bártolo, P. J.
In last decades, many advances have been made in order to aid the medical community. Numerous computational technologies have been developed and improved the efficiency in diagnostic and treatment of many diseases. Many of the technologies were developed with the main goal of aiding in the research of genetic and viral diseases. Tissue engineering is a multidisciplinary field that requires the combined effort of cell biologists, engineers, material scientists, mathematicians, geneticists, and clinicians toward the development of biological substitutes that restore, maintain, or improve tissue function. The success of this emerging medical domain relies on the current technological advances. This paper presents an overview of the existing computational technologies that have been implemented in tissue engineering and the design of scaffolds for tissue engineering applications. These computational technologies contemplate medical imaging processing, numerical calculations (structural, vascular and topological) and biofabrication techniques necessary for the scaffolds optimum design and production.