A Formal Method for Modeling, Verification and Synthesis of Embedded Reactive Systems

Embedded reactive systems are now invisible and everywhere, and are adopted, for instance, to monitor and control critical tasks in cars, airplanes, traffic, and industrial plants. However, the increasing amount of new functionalities being moved to software leads to difficulties in verifying the design correctness. In this context, we propose a novel design method called BARE Model, which is a formal abstraction to design, verify and synthesize software in embedded reactive applications. The method consists in designing the application using an extension of the well-known finite state machine, called X-machine. We thus propose to translate this model to a tabular data structure, which is a kind of state transition table augmented with memory input, memory output, and condition (or guard). This tabular structure may be automatically translated to the input of the NuSMV model checker in order to verify the system’s properties. We also propose a runtime environment to execute the system (expressed as a tabular data structure) in a specific platform. In this way, we can convert the high-level specification into executable code that runs on a target platform. To show the practical usability of our proposed method, we experimented it with the Envirotrack case study. The experiment shows that the proposed method is able to not only model the system, but also to verify safety and liveness properties, and synthesize executable code of real-world applications

Testing the use of radial basis function augmented with polynomials as basis functions in the boundary element method for heat transfer problems

The accuracy of the numerical solution obtained by the Boundary Element Method (BEM) is directly affected by the type of interpolation function used. Meanwhile, interpolation by radial basis function augmented with polynomials has been shown to be more accurate than Lagrange interpolation for a range of different functions. Therefore, this paper is concerned with the application of such functions as the interpolation functions for all boundary values in the boundary element method for the numerical solution of two-dimensional heat transfer problems. Numerical examples with different geometries and temperature distributions are presented and comparisons with both isogeometric and classical formulation are made to demonstrate the accuracy of the proposed method

A abordagem de ligaçao química numa perspectiva de ensino por situação-problema

Esta investigação retrata um estudo realizado junto a estudantes do primeiro período do Curso de Licenciatura Plena em Química da Universidade Federal Rural de Pernambuco. Foi realizada uma intervenção didática utilizando uma situação-problema vinculada a instrumentos didáticos sobre ligação iônica e metálica. Ficou evidenciado que a utilização da situação-problema e dos instrumentos didáticos contribuiu para aprendizagem dos estudantes em relação aos aspectos conceituais relativos às ligações químicas

Physics of Brain Folding

The human brain is characterized by its folded structure, being the most folded brain among all primates. The process by which these folds emerge, called gyrogenesis, is still not fully understood. The brain is divided into an outer region, called gray matter, which grows at a faster rate than the inner region, called white matter. It is hypothesized that this imbalance in growth -- and the mechanical stress thereby generated -- drives gyrogenesis, which is the focus of this thesis. Finite element simulations are performed where the brain is modeled as a non-linear elastic and growth is introduced via a multiplicative decomposition. A small section of the brain, represented by a rectangular slab, is analyzed. This slab is divided into a thin hard upper layer mimicking the gray matter, and a soft substrate, mimicking the white matter. The top layer is then grown tangentially, while the underlying substrate does not grow. JuFold, the software developed to perform these simulations, is introduced, and its design is explained. An overview of its capabilities, and examples of simulation possibilities are shown. Additionally, one patent-leading application of JuFold in the realm of material science showcases its flexibility. Simulations are first performed by minimizing the elastic energy, corresponding to the slow growth regime. Systems with homogeneous cortices are studied, where growth initially compresses, and then buckles the cortical region, which generates wavy patterns with wavelength proportional to cortical thickness. After buckling, the sulcal regions (i.e. the valleys of the system) are thinner than the gyral regions (i.e. the hills). Introducing thickness inhomogeneities along the cortex lead to new and localized configurations, which are strongly dependent not only on the thickness of the region, but also on its gradient. Furthermore, cortical landmarks appear sequentially, consistent with the hierarchical folding observed during gestation. A linear stability theory is developed based on thin plate theory and is compared with homogeneous and inhomogeneous systems. Next, we turn to more physically stringent dynamic simulations. For slow growth rate and time-constant thickness, the results obtained through energy minimization are recovered, justifying previous literature. For faster growth, an overshoot of the wavenumber and a broad wavenumber spectrum are observed immediately after buckling. After a relaxation period, where the average wavenumber decreases and the wavenumber spectrum narrows, it is observed that the system stabilizes into a finite spectrum, whose average wavelength is smaller than that expected from energy minimization arguments. Cortical inhomogeneities are further explored in this new regime. Systems with inhomogeneous cortical thickness are revisited, with effects similar to the homogeneous cortex (i.e., results are consistent between the slow growth and the quasistatic regimes, and overshoot is observed in the fast growth regimes). Systems with inhomogeneous cortical growth are simulated, with this new type of inhomogeneity inducing fissuration and localized folding. The interplay between these two inhomogeneities is studied, and their interaction is shown to be nonlinear, with each inhomogeneity type inhibiting the folding effects of the other. That is, the folding profile of each individual region emerges as a result of the local inhomogeneity, and the system does not display an intermediate behavior. Finally, these results are compared with an extended linear stability theory. Taken together, our simulations and analytical theory expose new phenomena predicted by an incremented buckling hypothesis for folding and show a series of new avenues which could give rise to the important cortical features in the mammalian brain, especially those related to higher-order folding

A resolução de problemas no química no ix congreso internacional sobre investigación en didáctica de las ciencias

Este estudo analisou os trabalhos sobre a resolução de problemas em Química apresentados no IX Congreso Internacional sobre Investigación en Didáctica de las Ciencias. Nos anais desse evento foram identificadas dez (10) pesquisas sobre esse tema. Essas pesquisas foram analisadas a partir de quatro aspectos: (i)- linha de pesquisa; (ii)- método; (iii)- sujeitos; (iv)- conteúdos. De acordo com os resultados, a linha de pesquisa predominante foi a investigativa. Além disso, a maioria dos estudos utilizou o método qualitativo e apresentou como sujeitos de pesquisa alunos do Ensino Médio. Em relação aos conteúdos, observou-se a diversidade de conhecimentos químicos. A análise permitiu esboçar um perfil das pesquisas sobre a resolução de problemas em Química e verificar como esses estudos vêm se desenvolvend

Aplicação filosófica da tradução do grego – versões e interpretações

O objetivo dessa comunicação é mostrar a importância do trabalho de tradução, de comparação e de refacção de versões em vista da melhor interpretação filosófica, especialmente em passagens complexas dos antigos filósofos gregos. Por meio do estudo sistemático dos trechos e de suas versões, nas oficinas se constrói uma maior aproximação e compreensão dos textos originais. Essa apresentação procura exemplificar alguns desses casos. Assim, ficará manifesta a importância desse exercício de tradução especializada para o trabalho da pesquisa em filosofia antiga ou qualquer disciplina que resgate esses textos clássicos

Análise experimental de vigas em concreto armado com furo na alma próximo ao apoio utilizando armadura de reforço

Artigo submetido ao Curso de Engenharia Civil da UNESC - como requisito parcial para obtenção do Título de Engenheiro Civil.Na construção civil os furos e aberturas em vigas de concreto armado são muito utilizados, resultado muitas vezes da falta de compatibilização dos projetos complementares. O presente trabalho apresenta uma análise experimental de vigas em concreto armado com furo próximo ao apoio. Para isso foram moldadas três vigas de alma cheia como referência e seis vigas com furo na região de apoio, sendo que dessas seis, três receberam uma armadura de reforço. O modelo de ensaio foi de uma viga bi-apoiada, com uma única força concentrada, aplicada de forma lenta e crescente até a ruptura a uma distância de 2,5h (altura da viga) do apoio conforme norma européia EN:1168 (2005). Após o carregamento foram coletadas informações relacionadas à fissuração e deformação no ELU e a carga de ruptura das vigas. De posse dos resultados, observou-se que as vigas com armadura de reforço tiveram um melhor desempenho no aparecimento e abertura de fissuras e uma maior capacidade de carga quando comparadas as vigas sem armadura de reforço e até mesmo com as vigas de alma cheia

Litíase sintomática em vesícula biliar residual

Sintomas pós-colecistectomia muitas vezes têm causas extra-biliares. As causas biliares mais comuns são presença de cálculos ou cirurgia incompleta. O uso da colangiorressonância magnética pode evitar complicações intraoperatórias decorrentes anatomia biliar pouco usual facilitando o acesso cirúrgico. No presente trabalho é relatado caso de paciente com litíase sintomática em vesícula residual.Most post cholecystectomy symptoms have extrabiliary causes. The most common biliary causes are calculi and incomplete surgery. The use of magnetic resonance cholangiography (MRC) seems to avoid intraoperative complications due to a possible unusual biliary anatomy and to facilitate surgical access. Here in is reported a case of patient with symptomatic lithiasis in residual gallbladder

Orofacial Esthetic Scale and Psychosocial Impact of Dental Aesthetics Questionnaire: Development and psychometric properties of the Finnish version

To develop the Finnish version of the Orofacial Esthetic Scale (OES-Fi) and the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ-Fi) and estimate the psychometric properties of these instruments applied to adult Finns.info:eu-repo/semantics/publishedVersio