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- Data compression algorithms for biomedical imagesPublication . Faria, Sérgio; Cunha, Francisco; Parracho, João; Thomaz, Lucas; Assunção, PedroThe design of more efficient data structures, as well as the adoption of good information management practices applied to bioimage data, constitute very relevant initiatives. One such intervention is data compression and this text provides an overview and description of the main image compression methods, as well as an exposition of the potential of certain image formats according to specific application requirements, while ensuring the preservation of the data integrity.
- FSplines: A Software for Linear Stability Analysis of Thin-Walled Structures, Version 2.0Publication . Chicaiza, Ángel; Prola, Luis; Gala, Pedro; Chicaiza, Cristhian; Ortiz, MarciaFSplines is a (geometrically) linear stability analysis tool of thin-walled structures with open section (useful for cold-formed steel profiles), that enables obtaining the bifurcation stresses (critical stress, load and moment) and the respective buckling modes by the Finite Strip Method (FSM). The Finite Strip Method: (i) allows analyzing prismatic steel members (commercial structural profiles), (ii) is an alternative to the Finite Element Method (FEM), and (iii) has some important advantages over FEM. In the present article, two variants of the FSM are presented: (i) the Semi-Analytical Finite Strip Method (SAFSM), where use is made of trigonometric functions and (ii) the Splines Finite Strip Method (SFSM), employing spline functions. The SAFSM has the advantage of being less time consuming. Its main restriction is the fact that it only allows modelling simple supported members (pinned restrained). The SFSM most important advantage is the ability to model members with all kinds of boundary conditions. This method is, however, more time consuming. It is worth noting that the bifurcation analysis, performed by the computer application FSplines, is required for the design of cold formed members according to the specifications of international standards. FSplines 2.0 is the second version of the computer application here presented. In this second improved version more cross-sections are available, and more section properties are presented.
- Assessment of Seismic Behavior of an RC Precast BuildingPublication . Vitorino, Hugo; Batalha, Nadia; Sousa, Romain; Fernandes, Paulo; Varum, Humberto; Rodrigues, HugoPast earthquakes brought attention to the poor performance of precast reinforced concrete structures. One of the problems observed in those structures is related to the beam-to-column connections. The evaluation of different methodologies for the analysis of beam-to-column connections in industrial buildings is an important aspect that should be studied. The numerical analyses developed allowed the study of the effect that different connection properties have on the frequencies of vibration, members drifts, and seismic coefficients. The connection properties were modeled through a macro-element that considers the friction (between concrete–concrete and concrete–neoprene) and the steel dowels. The results showed that the friction between concrete elements and the consideration of the neoprene in the connection has a small impact on the drifts demands in the columns and seismic coefficient of the analyzed structure; on the other hand, the effect of the steel dowel on the drift demand and seismic coefficient is significant. The comparison of the models with different properties and connections allowed a better understanding of the factors with a higher impact on the results.
- IntroductionPublication . Gaspar, Florindo; Rodrigues, Hugo; Fernandes, Paulo; Mateus, Artur; Artur MateusThis first Conference on Automation and Innovation in Construction (CIA2019) aimed to be a reference forum for scientific discussion of technological developments in the field of innovation on automation in the construction industry. The conference started with several examples of BIM applications to different uses in the construction sector, from design to rehabilitation and maintenance, examples of robotics applied to constructions inspection have been shown, new methodologies and approaches to support decisions or the use of augmented reality and additive manufacturing in construction have been presented, namely, an example of application to space construction.
- Optimizing regions for characterization of thermal images in medical applicationsPublication . Duarte, A.; Carrão, L.; Espanha, M.; Viana, T.; Freitas, D.; Bártolo, P.; Faria, P.; Almeida, H.Biomedical techniques and applications are being developed and placed at the service of clinicians. An example is medical thermography which is being used more often in the detection of certain diseases and also in pain distribution. Current thermography processing software has some limitations mainly because it is developed for general applications and doesn't allow the identification of a Region Of Interest (ROI) with a specific anatomic shape. In this research, a computational application was developed in order to aid in the characterization of thermal images. The limitations of existing software applications was overcome by designing an application that allows choosing any ROI, independently of its geometric shape, making the analysis, processing and comparison of different thermal images, easier to be used by the medical community.
- Extensions of Dorfman’s TheoryPublication . Santos, Rui; Pestana, Dinis; Martins, João PauloEconomic impact of composite sampling is investigated in the realistic framework of tests with positive probability of false positive and of false negative results. Sensitivity and specificity when pooling samples are also discussed, using rarefaction as a framework.
- Conducting Polymer‐Based Flexible Supercapacitor DevicesPublication . Torvi, Anand I.; Naik, Satishkumar R.; Hegde, Sachin N.; Mulla, Mohemmedumar; Kamble, Ravindra R.; Mitchell, Geoffrey R.; Kariduraganavar, Mahadevappa Y.Flexible supercapacitors are gaining considerable attention because of their wide range of applications in the area of flexible electronics. Significant opportunities exist and will continue to exist for the development of flexible energy storage devices through intensive research. The level of R&D activity in the general field of energy storage technology has been rising considerably all over the world during the last two decades, because of the growing recognition of the commercial potentialities of energy storage technology. This chapter focuses on the different types of conducting polymer-based supercapacitors, incorporating polymers such as polyaniline, polypyrrole, polythiophene, and the derivatives of polythiophene. Emphasis is given to the methods of fabricating flexible supercapacitor devices. The different electrolytes employed for the development of flexible supercapacitors are discussed. In the beginning, a brief account of the principles and classification of supercapacitors is described. The chapter concludes with a consideration of the prospects for flexible supercapacitor. To compile this chapter and to provide adequate information to the readers, we have explored all the possible materials available in the literature.
- Distribution of the Number of Losses in Busy-Periods of Mx/G/1/n SystemsPublication . Ferreira, Fátima; Pacheco, António; Ribeiro, HelenaThis chapter addresses MX=G=1=n queues, i.e., single server batch Markovian arrival queues with finite customer waiting space of size n. Taking profit of the Markov regenerative structure of these systems, we develop an efficient recursive procedure to compute the probability mass function of the number of losses in busy-periods starting with an arbitrary number of customers in the system. The derived computational procedure is easy to implement and leads to a fast numerical computation of the loss probabilities. To illustrate the effectiveness of the procedure, loss probabilities are computed for a wide variety of queues, with different capacities, batch size distributions, and arrival and service parameters.
- Pareto Scale MixturesPublication . Felgueiras, Miguel MartinsPareto scale mixtures are very effective for modelling heavy-tailed data. A new class of models is described, generalizing commonly used slash distributions. Mixture properties and possible applications are discussed.
- Operation of Multi-MicrogridsPublication . Lopes, João Abel Peças; Madureira, André; Gil, Nuno; Resende, Fernanda; Nikos HatziargyriouThis chapter aims at studying the management of distribution networks with an increased Microgrid penetration, i.e. corresponding to a situation where most of the Low Voltage (LV) networks turn into active Microgrids. It is therefore assumed that the Microgrid concept is extended, leading to the development of a new concept – the Multi-Microgrid [1]. A full exploitation of this concept involves the design of new control architecture as well as the development of new management tools or the adaptation of existing Distribution Management Systems (DMS) tools.