On the asymptotic behaviour of the characteristics in the codiffusion of radioactive isotopes with general initial data

The large-time behaviour of the solution of a hyperbolic- parabolic problem in an isolated domain, which models the diffusion of n species of radiative isotopes of the same element, is studied, assuming general hypotheses on the initial data. Depending on the radiative law and on the distribution of the initial concentration, either a uniform distribution for the concentration of each isotope or the presence of oscillations may be possible when t → ∞

Polymer Crystallization Waves

We prove the existence of travelling wave solutions for a polymer crystallization model. The mathematical problem governing the process consists in a system of two coupled first order PDE, the heat equation with a source term for the temperature and the isokinetic law, involving an order parameter $\psi \in$ [0, 1], whose extreme values correspond to pure phases

La consommation des algues alimentaires en France. Synthèse de résultats. Cellule Etude et Transfert

La consommation des algues alimentaires en France, a été appréhendée grâce à deux méthodes complémentaires : des enquêtes en face à face et des groupes de discussion (focus groups) . Les enquêtes ont été réalisées en 2013 auprès de plus de 800 enquêtés, dans 7 grandes villes : Bordeaux, Lille, Lyon, Montpellier, Paris, Rennes et Strasbourg. Elles permettent d’obtenir des résultats quantifiables, à partir des entretiens individuels directifs. Les focus groups ont été réalisés en 2014 dans 5 grandes villes : Bordeaux, Lille, Montpellier, Paris et Rennes, avec la participation de plus de 80 personnes (consommateurs ou non d’algues alimentaires). Ces entretiens de groupe semi-directif permettent de recueillir des données qualitatives sur la perception des algues ainsi que sur les comportements et les motivations des consommateurs. N.B. : Les travaux du Pôle halieutique concernent uniquement les macro - algues, utilisées dans l’alimentation pour leurs propriétés organoleptiques. Les gélifiants et compléments alimentaires sont donc exclus de l’étude

On a Quasilinear Parabolic System Modelling the Diffusion of Radioactive Isotopes

We consider a model for the diffusion of N species of isotopes of the same element in a medium, consisting in a parabolic quasilinear system, with Dirichlet boundary condition, in the general hypothesis that the diffusion coefficients possibly are all different. We prove existence and uniqueness of classical solution in the physically relevant assumption that the total concentration of the element is positive and bounded

Ku & C Band solid state switch matrix for satellite payloads using LTCC multilayer substrate

This paper describes the design and development of Ku and C band solid state switch matrix for multimedia satellite payloads. The design, through the use of advanced packaging techniques, allows significant savings on mass and volume with respect to traditional electromechanical switches while guaranteeing a comparable reliability

Suspension Flows in a Pipeline with Partial Phase Separation

The formulation of a model for the evolution of the flow of a solid-liquid mixture (coal-water) in a horizontal pipeline with partial phase separation is the aim of this work. Problems of instabilities due to complex eigenvalues, observed in previous models, seem to be completely solved in the present model, in which we give the genesis of the different terms written in the equations, coming from the natural definition of mass and momentum balance, and the consequent proof of well-posedness of the obtained PDE system with boundary-Cauchy data. The model describes a three-layer flow. Most of the material is carried by the upper layer, while the bottom layer consists of an immobile sediment. The intermediate layer grows to a maximum thickness and has the role of regulating the mass exchange between the extreme layers. In the last section we present some simulations for a particular choice of flow regime, and boundary-Cauchy data, that were suggested by experimental results provided by Snamprogetti (Fano, Italy).Comment: 29 pages, 7 figure

Regional related variety and companies' productivity in Brazil

There is a discussion in the literature about the benefits that the regional diversity can result in the companies' productivity due to knowledge recombination, which allows greater opportunities to imitate, share and recombine ideas. However, few studies have been conducted in developing economies. This study aims to analyze the effects of the regional related variety (an indicator that captures the complementarity between sectors) on the companies' productivity. Also, we intend to verify whether the absorptive capacity is a significant moderator in this process and its thresholds. For the empirical study, a database containing data on 80 Brazilian municipalities and 194 companies was used, with data between 2010 and 2014. By calculating the related variety indicator to measure regional diversity and threshold regressions to measure absorptive capacity, this research contributes to the literature, given that empirical studies on this subject in Brazil are still limited. Besides, as the country has a diversified economy, we believe in recombination as an option for economic growth. The results indicate that the related variety has no significant effect on productivity when analyzed alone, but when moderated by the absorptive capacity it has a positive effect.Não recebi financiamentoHá uma discussão na literatura sobre os benefícios que a diversidade regional pode resultar na produtividade das empresas devido à recombinação do conhecimento, que permite maiores oportunidades de imitar, compartilhar e recombinar ideias. No entanto, poucos estudos foram realizados em economias em desenvolvimento. Este estudo tem como objetivo analisar os efeitos da variedade relacionada da região (indicador que capta a complementaridade entre setores) na produtividade das empresas. Além disso, pretendemos verificar se a capacidade de absorção é um moderador significativo neste processo e quais são seus limiares. Para o estudo empírico, uma base de dados contendo dados sobre 80 municípios brasileiros foi utilizada, com dados entre 2010 e 2014. Ao calcular o indicador de variedade relacionada para calcular a diversidade regional e regressões por limiar para medir a capacidade de absorção, esta pesquisa contribui com a literatura, dado que estudos empíricos sobre esse assunto no Brasil ainda são limitados. Além disso, como o país possui uma economia diversificada, acreditamos na recombinação como opção de crescimento econômico. Os resultados indicam que a variedade relacionada não tem efeito significativo na produtividade quando analisada isoladamente, mas quando moderada pela capacidade de absorção possui efeito positivo

Yi-Ping Ong, The Art of Being: Poetics of the Novel and Existentialists Philosophy

Review of Yi-Ping Ong's The Art of Being: Poetics of the Novel and Existentialists PhilosophyRecensione di The Art of Being: Poetics of the Novel and Existentialists Philosophy di Yi-Ping Ong