Integridad estructural

¿Cómo garantizar que nuestras estructuras son seguras y fiables? El conocimiento preciso del comportamiento de un elemento estructural cuando contiene defectos resulta imprescindible para la correcta predicción de su funcionamiento y su vida útil.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Driving Cars by Means of Genetic Algorithms

Proceedings of: 10th International Conference on Parallel Problem Solving From Nature, PPSN 2008. Dortmund, Germany, September 13-17, 2008The techniques and the technologies supporting Automatic Vehicle Guidance are an important issue. Automobile manufacturers view automatic driving as a very interesting product with motivating key features which allow improvement of the safety of the car, reducing emission or fuel consumption or optimizing driver comfort during long journeys. Car racing is an active research field where new advances in aerodynamics, consumption and engine power are critical each season. Our proposal is to research how evolutionary computation techniques can help in this field. As a first goal we want to automatically learn to drive, by means of genetic algorithms, optimizing lap times while driving through three different circuits.Publicad

Motion-Based Design of Passive Damping Devices to Mitigate Wind-Induced Vibrations in Stay Cables

Wind action can induce large amplitude vibrations in the stay cables of bridges. To reduce the vibration level of these structural elements, different types of passive damping devices are usually installed. In this paper, a motion-based design method is proposed and implemented in order to achieve the optimum design of different passive damping devices for stay cables under wind action. According to this method, the design problem is transformed into an optimization problem. Thus, its main aim is to minimize the different terms of a multi-objective function, considering as design variables the characteristic parameters of each considered passive damping device. The multi-objective function is defined in terms of the scaled characteristic parameters, one single-function for each parameter, and an additional function that checks the compliance of the considered design criterion. Genetic algorithms are considered as a global optimization method. Three passive damping devices have been studied herein: viscous, elastomeric and friction dampers. As a benchmark structure, the Alamillo bridge (Seville, Spain), is considered in order to validate the performance of the proposed method. Finally, the parameters of the damping devices designed according to this proposal are successfully compared with the results provided by a conventional design method

Effect of Vinyl Flooring on the Modal Properties of a Steel Footbridge

Damping ratios associated with non structural elements play an important role in mitigating the pedestrian-induced vibrations of slender footbridges. In particular, this paper analyses the effect of vinyl flooring on the modal parameters of steel footbridges. Motivated by the unexpected high experimental damping ratios of the first vibration modes of a real footbridge, whose deck was covered by a vinyl flooring, this paper aims at assessing more accurately the experimental damping ratios generated by this non-structural element on steel footbridges. For this purpose, a laboratory footbridge was built and vinyl flooring was installed on it. Its numerical and experimental modal parameters without and with the vinyl flooring were determined. The operational modal analysis method was used to estimate experimentally the modal parameters of the structure. The damping ratios associated with the vinyl flooring were obtained via the substraction between the experimental damping ratios of the laboratory footbridge with and without the vinyl flooring. An average increase of the damping ratios of 2.069% was observed due to the vinyl flooring installed. According to this result, this type of pavement may be a useful tool to significantly increase the damping ratios of steel footbridges in order to reduce pedestrian-induced vibrationsMinisterio de Economía y Competitividad DPI2014-53947-RFondo Europeo de Desarrollo Regional DPI2014-53947-

Evolving a rule system controller for automatic driving in a car racing competition

IEEE Symposium on Computational Intelligence and Games. Perth, Australia, 15-18 December 2008.The techniques and the technologies supporting Automatic Vehicle Guidance are important issues. Automobile manufacturers view automatic driving as a very interesting product with motivating key features which allow improvement of the car safety, reduction in emission or fuel consumption or optimization of driver comfort during long journeys. Car racing is an active research field where new advances in aerodynamics, consumption and engine power are critical each season. Our proposal is to research how evolutionary computation techniques can help in this field. For this work we have designed an automatic controller that learns rules with a genetic algorithm. This paper is a report of the results obtained by this controller during the car racing competition held in Hong Kong during the IEEE World Congress on Computational Intelligence (WCCI 2008).Publicad

Mejora de competencias en másteres universitarios: Nuevas experiencias con profesionales y empresas de artesanía

Acknowledgment This work was supported by Teaching Innovation Project “Laboratorio de estudios previos e informes sobre patrimonio histórico edificado” of the Master in Science and Technology in Heritage Architectural (CiTPA-Ugr) and University Master’s Degree in Architectural Rehabilitation (MARA-Ugr) was carried out under the auspices of Research Groups RNM 0179 and HUM 629 of the Junta de Andalucía. Also the author want to thank to the Unidad de Calidad, Innovación y Prospectiva de la Universidad de Granada, WARMEST and RRRMAKER Projects H2020-MSCA-RISE (Marie Skłodowska-Curie Research and Innovation Staff Exchange).This research evaluates the improvements that the use of Active Teaching and Learning Methodologies entails regarding the acquisition of professional skills of future graduates of the Masters dealing with intervention in Architectural Heritage, including product and resource improvements. The objectives address students’ training, oriented toward professional activity, determining the effectiveness of innovation. The real problems were exposed to be faced at a professional level and were solved through different parts, which were developed in different phases. The results obtained allowed us to conclude that teaching and performing practical tasks related to professional competencies are verified as an advance in the subject.Esta investigación evalúa las mejoras que supone el uso de Metodologías Activas de Enseñanza y Aprendizaje en la adquisición de competencias profesionales de los futuros egresados de los Másteres que aborden la intervención en el Patrimonio Arquitectónico, las cuales incluyen la mejora de productos y recursos. Los objetivos se centran en la formación del alumno, orientado a la actividad profesional, el cual determina la eficacia de la innovación. Se expusieron los problemas reales a afrontar y se desarrollaron en diferentes fases. Los resultados obtenidos permiten concluir que enseñar y realizar tareas prácticas relacionadas con las competencias profesionales ofrece buenos avances.Teaching Innovation Project “Laboratorio de estudios previos e informes sobre patrimonio histórico edificado” of the Master in Science and Technology in Heritage Architectural (CiTPA-Ugr)University Master’s Degree in Architectural Rehabilitation (MARA-Ugr)Research Groups RNM 0179 and HUM 629 of the Junta de AndalucíaUnidad de Calidad, Innovación y Prospectiva de la Universidad de GranadaWARMEST and RRRMAKER Projects H2020-MSCA-RISE (Marie Skłodowska-Curie Research and Innovation Staff Exchange

Una propuesta de desarrollo de la economía política constitucional: aplicación a un proceso constituyente internacional

El profesor Herber (1994), en este mismo foro, el año pasado en la conferencia inaugural, presentaba la hacienda pública internacional como una línea de investigación innovadora y precisa. Su justificación resultaba inmediata a partir de la constatación de la existencia de unos graves fallos de mercado que trascienden las fronteras estatales. Sin embargo, la consistencia con que se sostenía el componente teórico normativo de la nueva perspectiva chocaba con la dificultad de desarrollar la intervención política efectiva tendente a la superación de tales insuficiencias. Y es que en el plano supranacional, la imposición y el gasto público quedan muy mediatizados por la actitud recelosa de los Estados nacionales, que sólo delegan parcial y condicionadamente su soberanía en las instituciones diseñadas al efecto. Esta discontinuidad tiene su origen principal, según el propio Herber (1994, p.l), en que "el ámbito geográfico de la actividad económica internacional (supranacional) y el ámbito geográfico de la actividad política soberana (nacional) para afrontar esa actividad no se corresponden entre sí". En consecuencia, la virtualidad de una hacienda pública internacional queda a expensas de la sustanciación política de las medidas intervencionistas derivadas del primer análisis normativo. [...] Y como argumente Petersmann (1993), la libertad de mercado internacional requiere la misma protección constitucional garantizada al libre comercio interno. Luego, incluso asumiendo la hipótesis más radical de que los intercambios internacionales puedan llegar a ser plenamente satisfactorios en sus dimensiones asignativa y redistributiva, también es precisa una institución política soberana que explicite las reglas de juego básicas de ese mercado y medie en los posibles conflictos de intereses que surjan debido a interpretaciones divergentes. Del repaso de ambas vertientes podemos derivar que para hacer más eficiente la actividad económica mundial, en el sentido propuesto por North (1991, p.97) de "crear orden y reducir la incertidumbre en el intercambio", es necesario un componente político en las instituciones que la enmarcan para contribuir a la acción colectiva cooperativa, algo que, según Elster (1985, p.50), "es el problema más importante en las ciencias sociales, y el más difícil [...] debido a su inestabilidad e inaccesibilidad"

A crowd-structure interaction model to analyze the lateral lock-in phenomenon on footbridges

In this paper a simplified biomechanical crowd-structure interaction model is proposed and validated in order to analyse the lateral lock-in phenomenon on real footbridges. The proposed crowd-structure interaction model is organized in three levels: (i) pedestrian-structure interaction; (ii) interaction among pedestrians in the crowd; and (iii) interaction between the crowd and the structure. To this end, first, the human-structure interaction of each pedestrian is modelled via a simplified two degrees of freedom system. Second, the interaction among pedestrians inside the crowd is simulated using a multi-agent model. The considered model simulates the movement of each pedestrian from the dynamic equilibrium of the different social forces that act on him/her. Finally, the crowd-structure interaction is achieved modifying the behaviour of the pedestrians depending on the comfort level experienced. For this purpose, the recommendations established by the French standards have been considered. The integration of the three levels in an overall model is achieved by the implementation of a predictive– corrective method. The performance of the proposed model is validated correlating the numerical and experimental dynamic response of the Pedro e Inês footbridge during the development of a lateral lock-in pedestrian test. As the first lateral natural frequency of the footbridge is inside the range that characterizes the walking pedestrian step frequency in lateral direction, numerical and experimental studies were performed to analyse its behaviour under pedestrian action. The agreement between the numerical and experimental results is adequate. However, further studies are recommended in order to generalize the proposed approach and facilitate its use during the design project of future footbridges.Ministerio de Ciencia DPI2014-53947-

Comportamiento dinámico de sólidos transversalmente isótropos

XII Congreso Nacional de Ingeniería Mecánica, celebrado en Bilbao en 1997La formulación del problema dinámico en medios homogéneos y elásticolineales se reduce a un conjunto de Ecuaciones Integrales de Contorno. & t a s ecuaciones se resuelven numéricamente, en el dominio de la frecuencia, mediante el Método de los Elementos de Contorno. Para ello resulta necesario el conocimiento de una solución fundamental (i.e., respuesta de un medio infinito a la aplicación de una carga concentrada armónica) que pueda ser eficientemente implementada en un programa de Elementos de Contorno. En este trabajo se presentan resultados, correspondientes a la difracción de ondas por una cavidad irunersa en un sólido transversalmente isótropo, obtenidos empleando la solución fundamental de Wang y Achenb.lch (1995) y las expresiones asintóticas de Buchwald (1959) para campo lejano