ENIDH - EMM - Artigo Científico
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- MediBot: An Ontology-Based Chatbot to Retrieve Drug Information and Compare its PricesPublication . Avila, Caio Viktor S.; Franco, Wellington; Venceslau, A. D. P.; Rolim, Tulio Vidal; Vidal, Vania M. P.; Pequeno, Valéria M.In this article, we present the MediBot. MediBot is a chatbot for querying drugs information. The presented system acted as a single access point for natural and simplified information retrieval of drugs, prices, and its risks. The chatbot has two modes of operation: Quick Response and Interactive modes. The first answers questions asked in natural language, while the second has three interactive tasks, namely Browser, Query, and Price Comparison. We present here the system architecture, the Linked Data Mashup’s construction process, and Chatbot MediBot’s activities modes, focusing on the new Price Comparison’s task. This task presents the best prices for medicines and their best potential substitutes extracted in real-time from the Web with the help of the information obtained from a linked data mashup.
- Assessment of Replacement of Metal Parts by BFRP Composites into a Highly Efficient Electrical PrototypePublication . Marat-Mendes, R.; Ribeira, D.; Reis, L.This work intends to evaluate the use of epoxy composite materials reinforced with basalt fibers as replacement to metallic mechanical parts of a highly efficient electrical prototype. The analysis of the behavior of the original metallic bracket was made and an optimization process was carried out in order to achieve the most suitable geometry and stacking sequence if produced in composite material. Finite element analysis using Siemens NX12 and experimental tests to the produced composite part were performed in order to access it. It was verified that the total weight of the composite part shows a 45% reduction. The composite part shows a higher deformation than the metallic one due to basalt fiber’s higher flexibility. However, the advantages added by the new component largely compensate for the disadvantages that may have been added without compromising its performance. Obtained results show that the use of basalt fiber reinforced composites as the material of mechanical parts of a highly efficient electrical prototype that is a good alternative.
- Mechanical and thermal buckling of functionally graded axisymmetric shellsPublication . Moita, J. S.; Araújo, A. L.; Soares, C. M. M.; Correia, V. F.The buckling analysis of functionally graded materials (FGM) axisymmetric plate-shell type structures under mechanical and termal loading is presented in this work. A numerical solution is obtained by expanding the variables in Fourier series in the circumferential direction and using conical frustum finite elements in the meridional direction. The finite element model, having two nodal circles and ten degrees of freedom per node, is based in the Kirchhoff-Love theory that includes the transverse shear deformations by introducing a penalty function, which corresponds to the first order shear deformation theory (FSDT), is suitable for both thin and thick axisymmetric plate/shell structures. The reduced number of finite elements, which are required to model even complex structures, combined with the use of a small number of discrete layers to model the continuous variation of the mechanical properties through the thickness of the structure, results in an extremely low computational time required for FGM buckling applications. An in-house program has been developed, and applications in a variety of axisymmetric shells are solved, including circular plates. The solutions obtained in mechanical and thermal buckling are discussed and compared with alternative models.
- Boundaries and profiles in the Wigner formalismoPublication . Dias, N. C.; Prata, J. N.We consider a quantum device contained in an interval in the context of the Weyl–Wigner formalism. This approach was originally suggested by Frensley and is known to be plagued with several problems, such as non-physical and non-unique solutions. We show that some of these problems may be avoided if one writes the correct dynamical equation. This requires the (non-local) infuence of the potential outside of the device and the inclusion of singular boundary potentials. We also discuss the problem of imposing boundary conditions on the Wigner function that mimic the efect of the external environment. We argue that these conditions have to be chosen with extreme care, as they may otherwise lead to non-physical solutions
- Partial Traces and the Geometry of Entanglement; Sufficient Conditions for the Separability of Gaussian States.Publication . Dias, N. C.; Gossan, M. de; Prata, J. N.The notion of partial trace of a density operator is essential for the understanding of the entanglement and separability properties of quantum states. In this paper, we investigate these notions putting an emphasis on the geometrical properties of the covariance ellipsoids of the reduced states. We thereafter focus on Gaussian states and we give new and easily numerically implementable sufficient conditions for the separability of all Gaussian states. Unlike the positive partial transposition criterion, none of these conditions is however necessary.
- Artemia salina model: An important tool to screen general toxicity samplesPublication . Ntungwe, Epole; Isca, Vera M. S.; Pereira, Paula; Cebola, Maria-João; Rijo, PatriciaMedicinal plants are a good source of novel therapeutic drugs, due to the phytochemicals present. Artemia, commonly known as brine shrimp, is a tiny halophilic invertebrate belonging to class Crustacean, which plays an important role in saline aquatic and marine eco-systems. Besides its usage in aquaculture, it is also highly valued for its application in toxicity detection and it is used in areas such as Ecology, Physiology, Ecotoxicology, Aquaculture and Genetics. Furthermore, Artemia based lethality assay (brine shrimp lethality assay, BSLA) is rapid, convenient and low cost. Presently, brine shrimp lethality assays are enormously employed in research and applied toxicology. It has been used in the study of natural products as a preliminary toxicity assay to screen a large number of extracts and compounds for drug discovery in medicinal plants. The aim of this review paper is to collect, organize, select and discuss the existing knowledge about the different uses of Artemia salina as a bench-top bioassay for the discovery and purification of bioactive natural products.
- Buckling behavior of composite and functionally graded material plates.Publication . Moita, José S.; Araújo, Aurélio L.; Correia, Victor Franco; Soares, C. M. Mota; Herskovits, JoséIn this work the formulation for linear buckling and for geometrically nonlinear analysis of laminated composite and functionally graded material (FGM) plates under mechanical uniaxial in-plane uniform loads, and thermal loads, is presented. An implemented finite element model based on a non-conforming triangular flat plate/shell element with three nodes and eight degrees of freedom per node, associated with a higher order shear deformation theory is used. The through the thickness variation of the material properties, discrete for laminated composite plates or continuous for FGM plates, as well as the through the thickness temperature distribution, originate a non-symmetry with respect to the middle-surface. Thus, in general, the occurrence of bifurcation-type buckling should be studied, and the transverse deflection at the centre of the plate could be a good indicator to anticipate this occurrence. The solutions of some illustrative examples involving different boundary conditions, composite lay-up, FGM variation of volume fractions, temperature distributions, material combinations, and boundary conditions are presented for benchmarking purposes, with emphasis for the plate transverse deflections. Linear solutions are compared with numerical alternative models. The occurrence of bifurcation-type buckling is discussed for several representative cases, the validity of the linear buckling solutions is addressed and nonlinear analyses have been performed for confirmation purposes.
- Vibrations of functionally graded material axisymmetric shells.Publication . Moita, J. S.; Araújo, A. L.; Correia, V. F.; Soares, C. M. M.The free-vibration analysis of functionally graded materials (FGM) axisymmetric plate-shell type structures are presented in this work. A numerical solution is obtained by expanding the variables in Fourier series in the circumferential direction and using conical frustum finite elements in the meridional direction. The finite element model, having two nodal circles and ten degrees of freedom per node, is based in the Kirchhoff-Love theory that include the transverse shear deformations by introducing a penalty function, and using one Gauss point integration scheme which gave excellent results for both thin and thick axisymmetric plate/shells structures. The reduced number of finite elements, which are required to model even complex structures, combined with the use of a small number of discrete layers to model the continuous variation of the mechanical properties through the thickness of the structure, result in an extremely low computational time required for FGM applications. An in-house program has been developed, and applications in a variety of axysimetric shells are solved, including circular plates. The solutions obtained are discussed and compared with solutions obtained by alternative models.
- Optimization of Metal–Ceramic Functionally Graded Plates Using the Simulated Annealing Algorithm.Publication . Franco Correia, Victor; S. Moita, J.; Moleiro, F.; M. Mota Soares, C.This work involves the design optimization of metal–ceramic through the thickness of functionally graded material (FGM) plates subjected to thermomechanical loadings. Constrained optimization was performed for minimum mass and minimum material cost of the FGM plates. The design process of FGM plate structures requires a good choice of metal and ceramic materials and the adequate definition of the components volume fractions through the thickness direction in order to accomplish a certain structural behavior, while optimizing the material costs and/or the plate mass. Here, the optimization problems are solved with the simulated annealing (SA) algorithm, not requiring the calculation of the derivatives of the objective or constraint functions. Constrained single objective optimization cases are studied, and validated with alternative solutions, considering the p-index and the FGM plate thickness as design variables. New optimization cases, involving additionally the metal and ceramic materials as design variables, are presented both for benchmark purposes and to demonstrate the suitability of the SA algorithm to solve those optimization problems.
- ENIDH desenvolve Projeto de I&DPublication . Assunção, M.; Franco, V.; Marat, R.; Fazenda, P.