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  • Modelling and Simulation of Several Interacting Cellular Automata

    Pla Castells, M.; García Fernández, I.; Martínez Durá, R. J.

    (2010). Article

    PROC. OF ISC. 2010. Cellular Automata are used for modelling and simulation of many systems. In some applications, the system is formed by a set of subsystems that can be modelled separately, but, in such cases, the existence of interactions between these subsystems requires additional modelling and computer programming. In this paper we propose a modelling methodology for the simulation of a set of Cellular Automata models that interact with each other. The modelling methodology is described, together with an insight on implementation details. Also, it is applied to a particular Cellular Automata model, the Sanpile Model, to illustrate its use and to obtain some example simulations.

  • Accelerating consensus gossip algorithms: Sparsifying networks can be good for you

    Asensio, C.; Beferull-Lozano, B.

    (2010). Article

    In this paper, we consider the problem of improving the convergence speed of an average consensus gossip algorithm by sparsifying a sufficiently dense network graph. Thus, instead of adding links, as usually proposed in the literature, or globally optimizing the mixing matrix of the gossip algorithm for a given network, which requires global knowledge at every node, we find a sparser network that has better spectral properties and faster convergence than the original denser one. This allows to reduce simultaneously both the convergence time and the communication cost involved in the execution of the gossip algorithm. We first show why it is possible to sparsify a network while increasing...

    In this paper, we consider the problem of improving the convergence speed of an average consensus gossip algorithm by sparsifying a sufficiently dense network graph. Thus, instead of adding links, as usually proposed in the literature, or globally optimizing the mixing matrix of the gossip algorithm for a given network, which requires global knowledge at every node, we find a sparser network that has better spectral properties and faster convergence than the original denser one. This allows to reduce simultaneously both the convergence time and the communication cost involved in the execution of the gossip algorithm. We first show why it is possible to sparsify a network while increasing its convergence rate and also that there exists an optimal fraction of links to be removed. As a benchmark, we devise a centralized method that selects in an optimal way the set of links to be removed from the original network. Then, we propose a low complexity and scalable decentralized protocol requiring only local information at each node, which also generates a sparser network having a substantially better convergence rate. Simulation results are presented to verify and show clearly the efficiency of our approach.

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  • Finding Sparse Connectivity Patterns in Power-Constrained Ad-hoc Networks for accelerating consensus algorithms

    Asensio, C.; Beferull-Lozano, B.

    (2010). Article

    In this paper, we show how to critically sparsify a given network while improving the convergence rate of the associated average consensus algorithm. Thus, instead of adding new links or reallocating them, we propose novel distributed methods to nd much sparser networks with better convergence results than the original denser ones. We propose two distributed algorithms; a) in the first one, each node solves a local optimization problem using only its two-hop neighborhood, b) the second one is a distributed algorithm based on using, at each node, the power method. As compared with previous work, the reduction in the number of active links is doubled while improving the convergence rate and...

    In this paper, we show how to critically sparsify a given network while improving the convergence rate of the associated average consensus algorithm. Thus, instead of adding new links or reallocating them, we propose novel distributed methods to nd much sparser networks with better convergence results than the original denser ones. We propose two distributed algorithms; a) in the first one, each node solves a local optimization problem using only its two-hop neighborhood, b) the second one is a distributed algorithm based on using, at each node, the power method. As compared with previous work, the reduction in the number of active links is doubled while improving the convergence rate and having a much lower power consumption. Simulation results are presented to verify and show clearly the eciency of our approach.

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  • On Multiterminal source coding for temperature sensing

    Beferull-Lozano, B.; Konsbruck, R.

    (2010). Article

    We study the source coding problem in sensor networks deployed to monitor the evolution of spatio-temporal temperature distributions. The sensors sample the temperature field, quantize the samples and transmit the encoded samples through digital channels to some central unit, which computes an estimate of the original temperature field. Our analysis is based on the heat kernel's spectral properties, which are induced by the physics of heat diffusion. We determine rate distortion functions for various source coding schemes. In particular, we compare centralized coding, independent coding, Berger-Tung coding, and predictive quantization.

  • CGVR'09: Integrating Virtual Environments with Multimedia contents in a Web Application

    Vera, Lucía; Coma, Inmaculada; Talón, Rubén; Fernández, Marcos

    (2009). Article

    Full article.

    In the present paper a system architecture for the combination, interaction and synchronization between different technologies is presented. Our system integrates 3D interactive virtual environments, 2D animations and games, avatars, form applications and documents, videos based in Chroma Key technology and other multimedia components. All of this inside a unique web application with a special objective, developing an interactive game for people who would like to become a self-employed worker. As the legal procedure (focused in the Spanish model) to start to be a sole trader is difficult and hard, we have developed a very intuitive, easy to use and enjoyable game to cover all information...

    In the present paper a system architecture for the combination, interaction and synchronization between different technologies is presented. Our system integrates 3D interactive virtual environments, 2D animations and games, avatars, form applications and documents, videos based in Chroma Key technology and other multimedia components. All of this inside a unique web application with a special objective, developing an interactive game for people who would like to become a self-employed worker. As the legal procedure (focused in the Spanish model) to start to be a sole trader is difficult and hard, we have developed a very intuitive, easy to use and enjoyable game to cover all information needed by these collective of people. The authors describe all the components of the architecture, the technologies used for developing each module and the combination and interaction between them to finally obtain this interactive game integrated inside a web application.

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  • JOREVIR'09: Interacción con Entornos Virtuales en Teléfonos Móviles

    Gimeno, Jesús; Coma, Inmaculada; Fernández, Marcos; Morillo, Pedro; Vera, Lucía

    (2009). Article

    Articulo completo.

    En este trabajo presentamos un sistema para la navegación en entornos virtuales 3D sobre teléfonos móviles. Tradicionalmente la interacción con el teléfono móvil se ha realizado utilizando el teclado como dispositivo de interacción. Sin embargo, gracias a las capacidades de los nuevos terminales es posible aprovechar dispositivos como la cámara incorporada o los acelerómetros para implementar interacciones basadas en movimientos naturales del usuario. En el presente trabajo hemos tratado de crear un mecanismo de interacción con entornos virtuales que sea adaptable a las tecnologías incorporadas en el teléfono, de forma que se pueda interaccionar bien interacción mediante las teclas, o bien...

    En este trabajo presentamos un sistema para la navegación en entornos virtuales 3D sobre teléfonos móviles. Tradicionalmente la interacción con el teléfono móvil se ha realizado utilizando el teclado como dispositivo de interacción. Sin embargo, gracias a las capacidades de los nuevos terminales es posible aprovechar dispositivos como la cámara incorporada o los acelerómetros para implementar interacciones basadas en movimientos naturales del usuario. En el presente trabajo hemos tratado de crear un mecanismo de interacción con entornos virtuales que sea adaptable a las tecnologías incorporadas en el teléfono, de forma que se pueda interaccionar bien interacción mediante las teclas, o bien capturar los movimientos del usuario haciendo uso de los acelerómetros o las imágenes capturadas por la cámara de vídeo. Para estimar el movimiento a partir de las imágenes capturadas se ha utilizado un algoritmo diferencial. Por último se ha diseñado un entorno 3D que permite el acceso a contenidos Web y multimedia.

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  • IPCV'09: A Device-Independent 3D User Interface for Mobile Phones Based on Motion and Tracking Techniques

    Gimeno, Jesús; Morillo, Pedro; Coma, Inmaculada; Fernández, Marcos

    (2009). Article

    Full article.

    The user interaction in mobile phones has been traditionally based on key behaviors that users have adapted around their mobile devices. Although this type of interaction could be suitable for some contents, it could be improved from the point of view of the usability. In this paper we present a new user interface based on 3D navigation oriented to mobile phones. To enhance the user experience, we have developed a new interface based on 3D real-time graphics where users interact by means of natural movements of their devices. The goals of this development consist in enhancing the user interaction and accessibility to web content or interactive multimedia applications by means of avoiding a...

    The user interaction in mobile phones has been traditionally based on key behaviors that users have adapted around their mobile devices. Although this type of interaction could be suitable for some contents, it could be improved from the point of view of the usability. In this paper we present a new user interface based on 3D navigation oriented to mobile phones. To enhance the user experience, we have developed a new interface based on 3D real-time graphics where users interact by means of natural movements of their devices. The goals of this development consist in enhancing the user interaction and accessibility to web content or interactive multimedia applications by means of avoiding a key-based, or a mouse-based, navigation and proposing a software solution adaptable to multiple and different mobile devices. In this sense, the user inputs can be detected by different input devices such as accelerometers or cameras, as well as the traditional keypads. Since mobile phones with on-board digital cameras are now widely available at low cost, the proposed 3D user interface exploits the acquisition capabilities of these input devices. In this sense, a differential algorithm has been applied in order to estimate phone movements from video images. The results of the performance evaluation of the 3D user interface shows that the proposed algorithm not only obtains a motion and tracking under extreme lighting conditions, but also adds an insignificant overhead to the system performance. Finally, a 3D environment has been designed to evaluate the performance of the presented approach, which has been successfully tested in actual users.

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  • CEIG'09: BIOMIMO, Estudio Ergonómico Aumentado Utilizando un Sistema de Captura de Movimiento Infrarrojo de Alta Precisión y Realidad Aumentada.

    Gimeno, Jesús; Gorosable, Maite; Sanchez, Fernando M.;Pujana-Arrese, Aron; Fernández, Marcos; Landaluze, Joseba

    (2009). Article

    Utilizando el Software desarrollado, llamado BIOMIMO estudio ergonómico aumentado, un experto puede observar al usuario durante el estudio, obteniendo una visualización aumentada del mismo. Para aumentar la visión del experto, el sistema de captura infrarrojo de alta precisión envía la información que se representan en forma de un esqueleto tridimensional superpuesto a la imagen del sujeto evaluado, y valores calculados en tiempo real (ángulos de estudio, posiciones relativas, etc.). Como resultado, el análisis del experto ya no solo se basa en su percepción, sino que en tiempo real tiene información exacta de los movimientos del brazo.

    Poster

  • Semantic traffic applications based on DatexII

    Samper, J. Javier; Adell, F. Javier; García, Jose Fco.;Martinez, J.José;Vidal,José

    (2009). Article

    EATIS2009 THE FOURTH EUROAMERICAN CONFERENCE ON TELEMATICS AND INFORMATION SYSTEMS .ACM-DL-Proceedings

    ISBN: 978-1-60558-398-3
  • Desarrollo y evaluación de un sistema tipo mesa interactiva basado en tecnología multi-touch.

    Sánchez Monserrat, Fernando Manuel

    (2009). Projecte fi de màster

    Proyecto completo.

    El propósito de este trabajo consiste en el análisis, diseño, construcción y evaluación de un sistema tipo mesa interactiva basado en tecnología de pantalla “Multi-Táctil”. Concretamente, este trabajo se centra tanto en el diseño y construcción del subsistema hardware del sistema (la propia mesa en sí), como en el análisis, diseño e implementación del subsistema software del mismo. Además de esto, se crearan algunas aplicaciones de prueba donde se comprobará si el sistema desarrollado realmente funciona. Estas aplicaciones comprobarán el funcionamiento tanto en Single-Touch como en Multi-Táctil. Esta tecnología está siendo utilizada cada vez más por industrias debido a que se están...

    El propósito de este trabajo consiste en el análisis, diseño, construcción y evaluación de un sistema tipo mesa interactiva basado en tecnología de pantalla “Multi-Táctil”. Concretamente, este trabajo se centra tanto en el diseño y construcción del subsistema hardware del sistema (la propia mesa en sí), como en el análisis, diseño e implementación del subsistema software del mismo. Además de esto, se crearan algunas aplicaciones de prueba donde se comprobará si el sistema desarrollado realmente funciona. Estas aplicaciones comprobarán el funcionamiento tanto en Single-Touch como en Multi-Táctil. Esta tecnología está siendo utilizada cada vez más por industrias debido a que se están produciendo grandes avances en ella, lo que le permite ser un perfecto complemento a los demás periféricos (ratón, teclado, botones, etc..) en los casos donde estos no cumplen con las expectativas que en un principio se espera de ellos. Todo esto hace que cada vez sea más aconsejable su implantación en sistemas de uso cotidiano.

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     Tutor proyecto: Pedro Morillo Tena