219 research outputs found

    Nidificación de Gorrión Común (Passer domesticus) en una grúa móvil

    Get PDF
    Es va trobar un niu de pardal comú situat a una grua d'una nau industrial el qual es movia contínuament distàncies de fins a 75 m. El moviment del niu no va afectar l'èxit reproductor dels pardals, els quals van alimentar els polls amb tota normalitat. Aquest lloc tan inusual d'ubicació del niu i d'altres casos publicats són exemples de l'alta adaptabilitat de l'espècie cap a indrets força humanitzats

    Nest Site Selection by Kentish Plover Suggests a Trade-Off between Nest-Crypsis and Predator Detection Strategies

    Get PDF
    Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator) decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of coastal regression and increase of recreational activities.Our work received partial funding only during the years 2000 and 2001 by the Conselleria de Infraestructuras, Territorio y Medio Ambiente (Generalitat Valenciana; www.citma.gva.es). PLL is supported by a “Juan de la Cierva” postdoctoral grant of the Spanish Ministry of Economy and Competitiveness (http://www.mineco.gob.es/) (reference JCI-2011-09588)

    Characterizing visual asymmetries in contrast perception using shaded stimuli.

    Get PDF
    Previous research has shown a visual asymmetry in shaded stimuli where the perceived contrast depended on the polarity of their dark and light areas (Chacón, 2004). In particular, circles filled out with a top-dark luminance ramp were perceived with higher contrast than top-light ones although both types of stimuli had the same physical contrast. Here, using shaded stimuli, we conducted four experiments in order to find out if the perceived contrast depends on: (a) the contrast level, (b) the type of shading (continuous vs. discrete) and its degree of perceived three-dimensionality, (c) the orientation of the shading, and (d) the sign of the perceived contrast alterations. In all experiments the observers' tasks were to equate the perceived contrast of two sets of elements (usually shaded with opposite luminance polarity), in order to determine the subjective equality point. Results showed that (a) there is a strong difference in perceived contrast between circles filled out with luminance ramp top-dark and top-light that is similar for different contrast levels; (b) we also found asymmetries in contrast perception with different shaded stimuli, and this asymmetry was not related with the perceived three-dimensionality but with the type of shading, being greater for continuous-shading stimuli

    A Practical Approach to the Development of Ontology-Based Information Fusion Systems

    Get PDF
    Proceedings of: NATO Advanced Study Institute (ASI) on Prediction and Recognition of Piracy Efforts Using Collaborative Human-Centric Information Systems, Salamanca, 19-30 September, 2011Ontology-based representations are gaining momentum among other alternatives to implement the knowledge model of high-level fusion applications. In this paper, we provide an introduction to the theoretical foundations of ontology-based knowledge representation and reasoning, with a particular focus on the issues that appear in maritime security –where heterogeneous regulations, information sources, users, and systems are involved. We also present some current approaches and existing technologies for high-level fusion based on ontological representations. Unfortunately, current tools for the practical implementation of ontology-based systems are not fully standardized, or even prepared to work together in medium-scale systems. Accordingly, we discuss different alternatives to face problems such as spatial and temporal knowledge representation or uncertainty management. To illustrate the conclusions drawn from this research, an ontology-based semantic tracking system is briefly presented. Results and latent capabilities of this framework are shown at the end of the paper, where we also envision future opportunities for this kind of applications.This research activity is supported in part by Projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008-06732-C02-02/TEC, CAM CONTEXTS (S2009/TIC-1485) and DPS 2008-07029-C02-02.Publicad

    ABP gamificado en la asignatura de tecnología con Arduino

    Get PDF
    El presente TFM titulado "ABP gamificado en la asignatura de tecnología con Arduino" responde a la necesidad del desarrollo de competencias en las aulas y de adecuar el aprendizaje a las nuevas exigencias sociales (emprendimiento, innovación y trabajo en equipo) y al alumno, entendiendo la motivación de éste como motor principal del proceso enseñanza-aprendizaje. En este TFM se propondrá un ABP (aprendizaje basado en proyectos) para alumnos de la asignatura de Tecnología de 4º de la ESO utilizando una placa Arduino. En la realización del proyecto los alumnos deberán dividir un problema complejo en partes más simples para poder llevar a cabo su resolución, de una forma muy parecida a como se desarrollan los proyectos en la realidad, y de esta manera lograr alcanzar un aprendizaje significativo. Para mantener un alto nivel de motivación frente a los momentos de frustración que se puedan dar y favorecer un entorno de trabajo inclusivo para todos los alumnos, se propondrá el añadir una capa de gamificación, destacando los siguientes elementos; una historia/contexto adecuado a los gustos del alumnado, identificación del alumno con un personaje y con su grupo, un sistema de recompensas por logros y una forma de trabajo inclusiva basada también en recompensas.<br /

    Topological Properties in Ontology-based Applications

    Get PDF
    Proceedings of: 11th International Conference on Intelligent Systems Design and Applications, Córdoba, Spain, 22 – 24 November, 2011.Representation and reasoning with spatial properties is essential in several application domains where ontologies are being successfully applied; e.g., Information Fusion systems. This requires a full characterization of the semantics of relations such as adjacent, included, overlapping, etc. Nevertheless, ontologies are not expressive enough to directly support widely-use spatial or topological theories, such as the Region Connection Calculus (RCC). In addition, these properties must be properly instantiated in the ontology, which may require expensive calculations. This paper presents a practical approach to represent and reason with topological properties in ontology-based systems, as well as some optimization techniques that have been applied in a video-based Information Fusion application.This work was supported in part by Projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008-06732-C02-02/TEC,CAM CONTEXTS (S2009/ TIC-1485) and DPS2008-07029-C02-02.Publicad

    Context-based scene recognition from visual data in smart homes: an Information Fusion approach

    Get PDF
    Ambient Intelligence (AmI) aims at the development of computational systems that process data acquired by sensors embedded in the environment to support users in everyday tasks. Visual sensors, however, have been scarcely used in this kind of applications, even though they provide very valuable information about scene objects: position, speed, color, texture, etc. In this paper, we propose a cognitive framework for the implementation of AmI applications based on visual sensor networks. The framework, inspired by the Information Fusion paradigm, combines a priori context knowledge represented with ontologies with real time single camera data to support logic-based high-level local interpretation of the current situation. In addition, the system is able to automatically generate feedback recommendations to adjust data acquisition procedures. Information about recognized situations is eventually collected by a central node to obtain an overall description of the scene and consequently trigger AmI services. We show the extensible and adaptable nature of the approach with a prototype system in a smart home scenario.This research activity is supported in part by Projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008- 06732-C02-02/TEC, CAM CONTEXTS (S2009/TIC-1485) and DPS2008-07029-C02-02.Publicad

    Ontological representation of time-of-flight camera data to support vision-based AmI

    Get PDF
    Proceedings of: 4th International Workshop on Sensor Networks and Ambient Intelligence, 19-23 March 2012, Lugano ( Switzerland)Recent advances in technologies for capturing video data have opened a vast amount of new application areas. Among them, the incorporation of Time-of-Flight (ToF) cameras on Ambient Intelligence (AmI) environments. Although theperformance of tracking algorithms have quickly improved, symbolic models used to represent the resulting knowledge have not yet been adapted for smart environments. This paper presents an extension of a previous system in the area of videobased AmI to incorporate ToF information to enhance sceneinterpretation. The framework is founded on an ontologybased model of the scene, which is extended to incorporate ToF data. The advantages and new features of the model are demonstrated in a Social Signal Processing (SSP) application.This work was supported in part by Projects CICYT TIN2011-28620-C02-01, CICYT TEC2011-28626-C02-02, CAM CONTEXTS (S2009/TIC-1485) and DPS2008-07029- C02-02.Publicad

    Applying the Dynamic Region Connection Calculus to Exploit Geographic Knowledge in Maritime Surveillance

    Get PDF
    Proceedings of: 15th International Conference on Information Fusion (FUSION 2012), Singapore, 9-12 July 2012.Concerns about the protection of the global transport network have risen the need of new security and surveillance systems. Ontology-based and fusion systems represent an attractive alternative for practical applications focused on fast and accurate responses. This paper presents an architecture based on a geometric model to efficiently predict and calculate the topological relationships between spatial objects. This model aims to reduce the number of calculations by relying on a spatial data structure. The goal is the detection of threatening behaviors next to points of interest without a noticeable loss of efficiency. The architecture has been embedded in an ontology-based prototype compliant with the Joint Directors of Laboratories (JDL) model for Information Fusion. The prototype capabilities are illustrated by applying international protection rules in maritime scenarios.This work was supported in part by Projects CICYT TIN2011-28620-C02-01, CICYT TEC2011-28626-C02-02, CAM CONTEXTS (S2009/TIC-1485) and DPS2008-07029- C02-02.Publicad
    corecore