24 resultados para Virtual elements


Relevância:

20.00% 20.00%

Publicador:

Resumo:

[ES] Los modelos virtuales de edificios hist??ricos u otros elementos patrimoniales cuentan con una gran variedad de aplicaciones relacionadas, sobre todo, con la difusi??n y multimedia. Aunque en muchas ocasiones se trata de productos eminentemente inform??ticos en los que la componente geom??trica y, por lo tanto topogr??fica, es muy limitada, existen aplicaciones, como los estudios hist??ricos, en los cuales, es necesario que estos modelos representen fielmente la geometr??a y las texturas. En estos casos, los modelos pueden considerarse como productos cartogr??ficos. A continuaci??n se hace una recapitulaci??n de las conclusiones a las que hemos llegado durante los ??ltimos dos a??os despu??s de haber desarrollado una veintena de proyectos en este campo.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

[ES] Ribera es un pueblo abandonado dentro del parque natural de Valderejo, el único edificio que queda en pie es la antigua iglesia. La razón por la que este edificio no fue derribado es la presencia de un conjunto de pinturas murales de época medieval. Por lo demás, el edificio (de unos 25 x 12 metros en planta) se encontraba en un mal estado de conservación (de hecho, un par de años más tarde de la realización de este trabajo se derrumbó la sacristía).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

El tramo litoral entre Deba y Zumaia constituye una de las zonas más conocidas y mejor estudiadas de todo el ámbito geológico de los Pirineos y, más particularmente, de su porción más occidental: la denominada cuenca o Región Vasco Cantábrica. Tal circunstancia deriva de los atributos particulares de su registro geológico: un potente conjunto de rocas sedimentarias de persistente estratificación, formadas en un antiguo fondo marino que, a pesar de grandes semejanzas, era muy distinto a los fondos marinos actuales. A este potente conjunto de rocas sedimentarias se le conoce bajo la denominación genérica de “flysch”, término de amplia raigambre geológica, cuya concepción y uso han cambiado considerablemente con el tiempo y el avance del conocimiento.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work presents the basic elements for the analysis of decision under uncertainty: Expected Utility Theory and its citicisms and risk aversion and its measurement. The concepts of certainty equivalent, risk premium, absolute risk aversion and relative risk aversion, and the "more risk averse than" relation are discussed. The work is completed with several applications of decision making under uncertainty to different economic problems: investment in risky assets and portfolio selection, risk sharing, investment to reduce risk, insurance, taxes and income underreporting, deposit insurance and the value of information.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

[ES]Este proyecto tiene como objeto aumentar el conocimiento concerniente a mecanismos robóticos reconfigurables, así como ponerlo en práctica. Estos mecanismos pueden lograr rápidas transiciones y son capaces de adaptarse a sí mismos a muchos entornos diferentes, conduciendo a una reducción de costes y requerimientos de espacio. Para ello, se estudia el estado del arte, de manera que se pueda reunir información sobre las principales aplicaciones y oportunidades que este campo ofrece en diferentes áreas. A continuación, se requiere llevar a cabo un análisis cinemático de un robot específico, y junto a métodos de planificación de trayectorias, su implementación en un software gráfico para simular su movimiento. La herramienta de software “Matlab” va a ser la que permitirá llevar a cabo toda la programación y representación a lo largo de todo el proyecto.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Grinding is an advanced machining process for the manufacturing of valuable complex and accurate parts for high added value sectors such as aerospace, wind generation, etc. Due to the extremely severe conditions inside grinding machines, critical process variables such as part surface finish or grinding wheel wear cannot be easily and cheaply measured on-line. In this paper a virtual sensor for on-line monitoring of those variables is presented. The sensor is based on the modelling ability of Artificial Neural Networks (ANNs) for stochastic and non-linear processes such as grinding; the selected architecture is the Layer-Recurrent neural network. The sensor makes use of the relation between the variables to be measured and power consumption in the wheel spindle, which can be easily measured. A sensor calibration methodology is presented, and the levels of error that can be expected are discussed. Validation of the new sensor is carried out by comparing the sensor's results with actual measurements carried out in an industrial grinding machine. Results show excellent estimation performance for both wheel wear and surface roughness. In the case of wheel wear, the absolute error is within the range of microns (average value 32 mu m). In the case of surface finish, the absolute error is well below R-a 1 mu m (average value 0.32 mu m). The present approach can be easily generalized to other grinding operations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In nickel-based superalloys, substitutional solute species have a strong impact on in service mechanical properties as well as on oxidation and corrosion resistances. In alloy 718, recent studies carried out by tensile tests highlighted the fact that refractory solute species are able to interact strongly with mobile dislocations during plastic deformation, generating dynamic strain ageing, and, in wide ranges of tests temperatures and strain rates, Portevin-Le Chatelier effect. The precise nature of the substitutional element responsible for such a dynamic interaction is still subject to debate. We addressed this question by means of mechanical spectroscopy studies of alloy 718 and various related alloys corresponding to monitored changes in the chemical composition. Only a single internal friction relaxation peak has been observed for all the studied alloys. By analyzing the damping behavior of these alloys at different imposed solicitation frequencies by sweeping a large temperatures range, the activation energies of the relaxation process and the type of mechanism involved have been determined. The process is a "Zener relaxation" in the alloys, i.e. a substitutional atoms dipole reorientation under applied stress. The results tend to prove that Niobium is not involved in the relaxation process whereas Molybdenum content seems to play an important role in the relaxation intensity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To achieve the apparently simple Periodic Table of the Elements has implied tremendous efforts over thousands of years. In this paper we present a brief history of the discovery of the chemical elements from prehistory to the present day, revealing the controversies that arose on the way and claiming the important work performed by alchemists in the advancement of knowledge. This is especially important if we consider that alchemy had a period of existence of many thousands of years, while the "Chemistry", officially established as a science in the eighteenth century, has operated as such for only a few hundred years. Even so, if we consider the progress of discovery and isolation of chemical elements throughout history, it can be observed that the number of elements identified is achieved mainly in the nineteenth and twentieth centuries, reflecting the development of instrumental techniques, that facilitated this task.