Griegos en el laberinto: el caldero Mediterráneo

Estamos habituados a la idea de que las raíces de nuestra cultura arrancan de Grecia. La insistencia en este punto trae consigo que en ocasiones no se mire más allá del siglo VI aC, como si a partir de ese punto se extendiese un insondable abismo. Pero quizá esas raíces griegas provengan, a su vez, de amalgamar elementos e influencias de tradiciones muy distintas. Veamos lo que podemos descubrir.We are used to consider that the origins of our culture are in Greece. Insistence on that point brings that we usually don’t look further on the VI century (BC), as if an unfathomable abyss would extend from there on. But maybe those Greek roots came, in turn, from amalgamating elements and influences from very different traditions. Let’s see what we can discover about that

A game-based approach to the teaching of object-oriented programming languages

Students often have difficulties when trying to understand the concepts of object-oriented programming (OOP). This paper presents a contribution to the teaching of OOP languages through a game-oriented approach based on the interaction with tangible user interfaces (TUIs). The use of a specific type of commercial distributed TUI (Sifteo cubes), in which several small physical devices have sensing, wireless communication and user-directed output capabilities, is applied to the teaching of the C# programming language, since the operation of these devices can be controlled by user programs written in C#. For our experiment, we selected a sample of students with a sufficient knowledge about procedural programming, which was divided into two groups: The first one had a standard introductory C# course, whereas the second one had an experimental C# course that included, in addition to the contents of the previous one, two demonstration programs that illustrated some OOP basic concepts using the TUI features. Finally, both groups completed two tests: a multiple-choice exam for evaluating the acquisition of basic OOP concepts and a C# programming exercise. The analysis of the results from the tests indicates that the group of students that attended the course including the TUI demos showed a higher interest level (i.e. they felt more motivated) during the course exposition than the one that attended the standard introductory C# course. Furthermore, the students from the experimental group achieved an overall better mark. Therefore, we can conclude that the technological contribution of Sifteo cubes – used as a distributed TUI by which OOP basic concepts are represented in a tangible and a visible way – to the teaching of the C# language has a positive influence on the learning of this language and such basic concepts

Sediment transport models in Shallow Water equations and numerical approach by high order finite volume methods.

This paper is concerned with the numerical approximation of bedload sediment transport due to water evolution. For the hydrodynamical component we consider Shallow Water equations. The morphodynamical component is defined by a continuity equation, which is defined in function of the solid transport discharge. We present several deterministic models, such as Meyer-Peter & Müller, Van Rijn or Grass model. We also present an unified definition for the solid transport discharge, and we compare with Grass model. Both components define a coupled system of equations that can be rewrite as a non-conservative hyperbolic system. To discretize it, we consider finite volume methods with or without flux limiters and high order state reconstructions. Finally we present several tests, where we observe numerically the order of the numerical schemes. Comparisons with analytical solutions and experimental data are also presented

Optimización matemática en problemas de la Física

In this work, Spin Glasses with Ising Sping model are studied. The objetive is the computation of the magnetic partition function and the search of the groung state. When we consider a two-dimensional lattice the problems can be solved in polynomial time depending on the size of the lattice. Nevertheless, we find a NP-hard problem in the two-dimensional within a magnetic field or the three-dimensional Spin Glass model. We’ll finally solve the two-dimensional problem with optimization algorithms.Universidad de Sevilla. Doble Grado en Física y Matemática

Esquemas 2D de alto orden basados en reconstrucciones de estado, para sistemas hiperbólicos no conservativos. Aplicación a problemas de transporte de sedimentos

En este trabajo se aborda la aproximación numérica del problema de arrastre de sedimentos causada por la evolución del agua. Para la componente hidrodinámica se consideran las ecuaciones de aguas poco profundas. La componente morfodinámica se define mediante una ecuación de continuidad, dada en función del caudal sólido. Ambas componentes constituyen un sistema acoplado que puede reescribirse como un sistema hiperbólico no conservativo (ver [4] A.M. Ferreiro Ferreiro. Desarrollo de técnicas de post-proceso de flujos hidrodinámicos, modelización de problemas de transporte de sedimentos y simulación numérica mediante técnicas de volúmenes finitos. Tesis Doctoral. Universidad de Sevilla. 2006). Se propone un esquema 2D generalizado de Roe con reconstrucciones de estado para sistemas hiperbólicos no conservativos (ver [4]), mediante esquemas de volúmenes finitos y el método de líneas (ver [5] J.A. García Rodríguez. Paralelización de esquemas de vol´umenes finitos: aplicación a la resolución de sistemas de tipo aguas someras. Tesis Doctoral. Universidad de Málaga. 2005), extendiendo los esquemas de alto orden para el caso 1D propuesto en [2] M.J. Castro, J.M. Gallardo and C. Parés. High order finite volume schemes based on reconstruction of states for solving hyperbolic systems with nonconservative products. Applications to shallow water systems. Math. Comp., 75: 1103-1134. 2006. La reconstrucción de estado empleada es de tipo MUSCL (ver [1] B. Van Leer. MUSCL. A new approach to numerical gas dynamics. Computing in plasma physics and astrophysics, Max-Planck-Institut fur plama physik.. Carchung, Germany, April 1976), que proporciona orden dos para mallas no estructuradas de volúmenes finitos de tipo arista. Finalmente se presenta un test num´erico en el que se estudia la evolución del ángulo de expansi´on de una monta˜na de arena (ver [4])

Calibragem e manutenção de dispositivos laser de baixa potência: estudo descritivo

Introduction: The low-power laser is a technique used in several areas of health: physiotherapy, dentistry, otorhinolaryngology and dermatology, among others. To achieve therapeutic effects, the dosage is essential and depends on the energy levels emitted by the device. Objective: To know the status of calibration and maintenance of low power laser therapy devices, in physiotherapy services or counterparts of institutions in Montevideo - Uruguay. Method: A descriptive, cross-sectional study was conducted in physiotherapy services in Montevideo, Uruguay. 20 low-power laser devices were analyzed. Results: 7 of the devices evaluated remained within the appropriate emission limits. Of the 13 lasers outside the limits to deliver adequate emission, 6 had a slight mismatch, 1 had a moderate mismatch, and 6 presented a severe mismatch. Among the total devices evaluated, only 6 had performed a previous calibration and only 2 of these were within the recommended times frames. Conclusion: A large number of low-power laser devices with imbalances in their emission was observed. In most cases, low-power laser devices are not properly maintained. Equipment should be timely calibrated in order to offer safe and effective therapy to users.Introducción: El láser de baja potencia es una técnica utilizada en varias áreas de la salud: fisioterapia, odontología, otorrinolaringología y dermatología, entre otras. Para lograr los efectos terapéuticos la dosificación es fundamental y depende de los niveles de energía emitidos por los equipos. Objetivo: Conocer el estado de calibración y mantenimiento de los equipos de laserterapia de baja potencia, en servicios de fisioterapia u homólogos de instituciones de Montevideo, Uruguay. Método: Se realizó un estudio descriptivo, transversal en servicios de fisioterapia de Montevideo. Se analizaron 20 equipos de láser de baja potencia. Resultados: 7 de los aparatos evaluados se mantuvieron dentro de los límites adecuados de emisión. De los 13 láser fuera de los límites para entregar una emisión adecuada, 6 tenían un desajuste leve, 1 presentaba un desajuste moderado y 6 presentaban un desajuste severo con dosis nulas o que no generaban emisión. Del total de equipos evaluados solo 6 habían realizado una calibración previa y solo 2 de estos se encontraban dentro de los tiempos recomendados. Conclusión: Se observó un gran número de equipos de láser de baja potencia con desajustes en su emisión. En la mayoría de los casos no se lleva un correcto mantenimiento de los aparatos de láser de baja potencia. Se entiende relevante que los equipos sean calibrados para poder ofrecer una terapéutica segura y efectiva a los usuarios.Introdução: O laser de baixa potência é uma técnica utilizada em diversas áreas da saúde: fisioterapia, odontologia, otorrinolaringologia, dermatologia, dentre outras. Para obter efeitos terapêuticos, a dosagem é essencial e depende dos níveis de energia emitidos pelo equipamento. Objetivo: conhecer o estado de calibração e manutenção de equipamentos de laserterapia de baixa potência, em serviços de fisioterapia ou congêneres de instituições em Montevideu - Uruguai. Método: estudo descritivo, transversal, realizado em serviços de fisioterapia em Montevideo, Uruguai. 20 equipamentos de laser de baixa potência foram analisados. Resultados: 7 dos aparelhos avaliados permaneceram dentro dos limites de emissão adequados. Dos 13 lasers fora dos limites para entregar a emissão adequada, 6 tiveram uma leve incompatibilidade, 1 teve uma incompatibilidade moderada e 6 apresentaram uma incompatibilidade grave. Do total de equipamentos avaliados, apenas 6 haviam realizado uma calibragem prévia e apenas 2 destes estavam dentro do prazo recomendado (1 ano). Conclusão: observou-se um grande número de equipamentos de laser de baixa potência com desequilíbrios em sua emissão. Na maioria dos casos, os dispositivos a laser de baixa potência não recebem manutenção adequada. Acredita-se importante que os equipamentos sejam calibrados para oferecer uma terapia segura e eficaz aos usuários