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- 3D shape prior active contours for an automatic segmentation of a patient specific femur from a CT scanPublication . Almeida, D.; Folgado, J.; Fernandes, P.R.; Ruben, RuiThe following paper describes a novel approach to a medical image segmentation problem. The fully automated computational procedure receives as input images from CT scan exams of the human femur and returns a three dimensional representation of the bone. This patient specific iterative approach is based in 3D active contours without edges, implemented over a level set framework, on which the evolution of the contour depends on local image parameters which can easily be defined by the user but also on a priori information about the volume to segment. This joint approach will lead to an optimal solution convergence of the iterative method. The resulting point cloud can be an excellent starting point for a Finite Element mesh generation and analysis or the basis for a stereolitography for example.
- Análise da Motivação Autodeterminada dos Praticantes de Trail RunningPublication . Coelho, Luís; Amaro, Nuno; Matos, Rui; Dias, Pedro; Morouço, Pedro
- 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.
- Biofabrication Strategies for Tissue EngineeringPublication . Bártolo, Paulo Jorge; Domingos, Marco; Patrício, Tatiana; Cometa, Stefania; Mironov, Vladimir; Bártolo, Paulo JorgeThe success of Tissue Engineering (TE) strongly relies on the capability of designing biomimetic scaffolds closely resembling the host tissue environment. Due to the functional multitude of the native tissues, the considerations are complex and include chemical, morphological, mechanical and biological factors and their mutability with time. Nonetheless, to trigger and/or assist the “natural healing mechanism’’ of the human body it seems essential to provide an appropriate biomechanical environment and biomolecular signalling to the cells. Novel biomanufacturing processes are increasingly being recognized as ideal techniques to produce 3D biodegradable structures with optimal pore size and spatial distribution, providing an adequate mechanical support for tissue regeneration while shaping in-growing tissues. In this chapter, we discuss in detail the most recent advances in the field of biofabrication, providing and updated overview of processes and materials employed in the production of tissue engineering constructs. Bioprinting or ‘’scaffold-less’’ strategies are also presented in this work. They are based on the precise deposition of high-density tissue spheroids or cell aggregates being advantageous alternatives to the current scaffold-based tissue engineering approach.
- Building insulation materials based on agricultural wastesPublication . Gaspar, Florindo; Bakatovich, Aliaksandr; Davydenko, Nadezhda; Joshi, ArpanEcological insulation materials of vegetable raw materials are increasingly widespread. The agricultural wastes can have an interesting role because their use allows the revaluation of agricultural wastes, whose disposal is a serious issue. This chapter gives an overview about the use of agricultural wastes on insulating materials. The source and characteristics of various types of wastes are described. The manufacturing processes considering the types of binders, including the main parameters involved, are explained. An overview is given about the properties of the insulation materials, including thermal conductibility, density, mechanical strength , hygroscopic behavior, acoustic and fire performances, and environmental performance. Suggestions regarding the future research needs are also presented.
- Chapter 8: Structure Development in Electrospun FibresPublication . 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 MitchellElectrospinning 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
- Comprehensive review on full bone regeneration through 3D printing approachesPublication . Fernandes, Cristiana; Moura, Carla; Ascenso, Rita M.T.; Amado, Sandra; Alves, Nuno; Pascoal-Faria, PaulaOver the last decades, the number of work accidents associated with bone fractures has increased leading to a growing concern worldwide. Currently, autografts, allografts, and xenografts are used for bone regeneration. However, their application has associated risks. Tissue engineering (TE) has brought solutions to address these problems, through the production of temporary supports, providing mechanical support to the formation of new bone tissue and biocompatible and biodegradable scaffolds, which allow cell adhesion and proliferation to ensure bone formation. The combination of materials and structure with the technique to be used will directly influence their physical and chemical properties and, consequently, their action in contributing to bone regeneration. Thus, the focus of this chapter is to perform an exhaustive literature review and a critical analysis of the state of the art in bone TE and present a proposal of an optimized temporary support geometry for bone regeneration in case of large bone defects. For this, it was listed and identified the best choice of biomaterials, fabrication method, cell type and their culture conditions (static vs. dynamic), and/or the inclusion of growth factors for the repair of large bone defects.
- 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.
- Controlling Morphology Using Low Molar Mass NucleatorsPublication . Mitchell, Geoffrey; Wangsoub, Supatra; Nogales, Aurora; Davis, Fred J.; Olley, Robert H.Crystallisation is a hugely important process in physical sciences and is crucial to many areas of, for example, chemistry, physics, biochemistry, metallurgy and geology. The process is typically associated with solidification, for example in the purification of solids from a heated saturated solution familiar to all chemistry undergraduates. Crystalline solids are also often the end result of cooling liquids, or in some cases gases, but in order to form require nucleation, in the absence of nucleation supercoiling of liquids well below the melting point is possible (Cava-gna, 2009). The quality of crystals, as gauged by size and levels of order is highly variable, and may depend on factors such as material purity and the rate of cool-ing; rapid cooling may result in poor crystallisation, or even the formation of amorphous materials with no long range order. In geological systems rates of cooling may vary over many orders of magnitude, for example obsidian is a large-ly amorphous material produced when lava is rapidly cooled (Tuffen, 2003), while the gypsum crystals found in the Cueva de los Cristales in Chihuahua, Mexico can reach 10 metres in length (Figure 1) and are formed over hundreds of thousands of years. In this latter case the formation of such large spectacular structures as shown in Figure 1 can only be explained by a low nucleation rate (García-Ruiz, 2007; Van Driessche, 2011).
- Design of Pyrolysis System to Convert Waste Plastic to FuelsPublication . Oliveira, Nelson S.; Pardo, Michael; Capela, Carlos; Gaspar, Marcelo; Vasco, Joel; Heleno, LizeteThe conventional recycling technology to process waste plastic, mechanical recycling, is not suitable to recycle waste thermoplastic with high content of contamination. Pyrolysis is a promising technology since it can convert into valuable products, such as fuels and monomers. This study focused on the design of the pyrolysis equipment for waste plastic based on polyolefins. The feeder of waste plastic is a worm screw conveyor that will be in a pre-heating system. The batch reactor has support for catalyzer and can operate between 300 up to 600 ºC with attached induction system for heating. The output flows into condenser in series to separate two liquid phases and gases, depending on its boiling point. The 3D model was done with SolidWorks, control system modelled in CADe SIMU and particle simulation with FloXpress.