5 resultados para Refined nonlinear non-conforming triangular plate element
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Resumo:
Este relatório descreve as atividades desenvolvidas durante o estágio curricular do curso de Mestrado Integrado em Medicina Veterinária no âmbito da inspeção sanitária e saúde pública, realizado tanto nos PIF de Lisboa, como na Divisão de Riscos Alimentares (DRA) da Autoridade de Segurança Alimentar e Económica (ASAE). Existe uma grande variedade de produtos e animais que chegam diariamente à União Europeia provenientes de diferentes países terceiros, como por exemplo a China, África do Sul, Brasil, Índia, Canadá e Senegal. Durante o período de estágio a categoria dos produtos mais inspecionada nos PIF foi o pescado representando 57,5% da totalidade das remessas inspecionadas nos portos de Lisboa e 98% no aeroporto. No âmbito do plano de fiscalização da ASAE em 2015, a aluna analisou 365 amostras de géneros alimentícios e constatou-se que o número de amostras não conformes foi 254. O grupo das bebidas alcoólicas destacou-se com 159 amostras não conformes; Abstract: National Control Plans of Food This essay describes the activities developed throughout the curricular internship of the Integrated Master of Veterinary Medicine within sanitary inspection and public health, both at border control of Lisbon as well as in the Divisão de Riscos Alimentares (DRA) of the Autoridade de Segurança Alimentar e Económica (ASAE). There is a wide variety of products and animals that arrive daily to the European Union from third countries, such as China, South Africa, Brazil, India, Canada and Senegal. During the internship the largest category of inspected food was fish representing 57.5% of the inspected remittances in the port of Lisbon and 98% in the airport. As part of the fiscalization plan of ASAE in 2015 the student analysed 365 food samples and it was found that the number of samples non-conforming was 254. The ardent spirits was the category that stood out with 159 non-conforming samples (63%).
Resumo:
With the theme of fracture of finite-strain plates and shells based on a phase-field model of crack regularization, we introduce a new staggered algorithm for elastic and elasto-plastic materials. To account for correct fracture behavior in bending, two independent phase-fields are used, corresponding to the lower and upper faces of the shell. This is shown to provide a realistic behavior in bending-dominated problems, here illustrated in classical beam and plate problems. Finite strain behavior for both elastic and elasto-plastic constitutive laws is made compatible with the phase-field model by use of a consistent updated-Lagrangian algorithm. To guarantee sufficient resolution in the definition of the crack paths, a local remeshing algorithm based on the phase- field values at the lower and upper shell faces is introduced. In this local remeshing algorithm, two stages are used: edge-based element subdivision and node repositioning. Five representative numerical examples are shown, consisting of a bi-clamped beam, two versions of a square plate, the Keesecker pressurized cylinder problem, the Hexcan problem and the Muscat-Fenech and Atkins plate. All problems were successfully solved and the proposed solution was found to be robust and efficient.
Resumo:
We propose an alternative crack propagation algo- rithm which effectively circumvents the variable transfer procedure adopted with classical mesh adaptation algo- rithms. The present alternative consists of two stages: a mesh-creation stage where a local damage model is employed with the objective of defining a crack-conforming mesh and a subsequent analysis stage with a localization limiter in the form of a modified screened Poisson equation which is exempt of crack path calculations. In the second stage, the crack naturally occurs within the refined region. A staggered scheme for standard equilibrium and screened Poisson equa- tions is used in this second stage. Element subdivision is based on edge split operations using a constitutive quantity (damage). To assess the robustness and accuracy of this algo- rithm, we use five quasi-brittle benchmarks, all successfully solved.
Resumo:
In this study, a finite element (FE) framework for the analysis of the interplay between buckling and delamination of thin layers bonded to soft substrates is proposed. The current framework incorporates the following modeling features: (i) geometrically nonlinear solid shell elements, (ii) geometrically nonlinear cohesive interface elements, and (iii) hyperelastic material constitutive response for the bodies that compose the system. A fully implicit Newton–Raphson solution strategy is adopted to deal with the complex simultaneous presence of geometrical and material nonlinearities through the derivation of the consistent FE formulation. Applications to a rubber-like bi-material system under finite bending and to patterned stiff islands resting on soft substrate for stretchable solar cells subjected to tensile loading are proposed. The results obtained are in good agreement with benchmark results available in the literature, confirming the accuracy and the capabilities of the proposed numerical method for the analysis of complex three-dimensional fracture mechanics problems under finite deformations.
Resumo:
This paper deals with the phase control for Neurospora circadian rhythm. The nonlinear control, given by tuning the parameters (considered as controlled variables) in Neurospora dynamical model, allows the circadian rhythms tracking a reference one. When there are many parameters (e.g. 3 parameters in this paper) and their values are unknown, the adaptive control law reveals its weakness since the parameters converging and control objective must be guaranteed at the same time. We show that this problem can be solved using the genetic algorithm for parameters estimation. Once the unknown parameters are known, the phase control is performed by chaos synchronization technique.