3,837 research outputs found

    Does Visual Spatial Awareness Require the Visual Awareness of Space?

    Get PDF
    Many philosophers have held that it is not possible to experience a spatial object, property, or relation except against the background of an intact awareness of a space that is somehow ‘absolute’. This paper challenges that claim, by analyzing in detail the case of a brain-damaged subject whose visual experiences seem to have violated this condition: spatial objects and properties were present in his visual experience, but space itself was not. I go on to suggest that phenomenological argumentation can give us a kind of evidence about the nature of the mind even if this evidence is not absolutely incorrigible

    The Digital Anatomist Spatial Abstraction: A Scheme for the Spatial Description of Anatomical Features

    Get PDF
    In this paper, we propose a generalized scheme for the symbolic description of the spatial attributes of anatomical entities. The power of the scheme lies in the ability to model the spatial objects at the highest level of granularity: information can be obtained at the desired level of detail needed for a given application. This scheme uses the topological classes of point, line, surface, and volume to represent zero-D, one- D, two-D and three-D objects. A spatial object participates as a node in three complementary networks; the topology network, the part-of network, and the spatial associations network. The topology network describes a spatial object in terms of its boundaries, the part-of network describes a spatial object in terms of its parts, and the spatial associations network describes the spatial object in terms of its relationships to other spatial objects. All three of the networks can be used in combination or alone to answer queries to the spatial information system. The Digital Anatomist Structural Abstraction together with the other components of the Digital Anatomist Foundational Model1 will provide the information for describing and reasoning about anatomical entities

    Spatial object recognition memory formation under acute stress

    Get PDF
    Stress is known to have a critical impact on memory processes. In the present work, we focus on the effects of an acute stress event closely associated to an unrelated learning task. Here, we show that acute stress (elevated platform [EP] session) experienced 1 hr after a weak spatial object recognition (SOR) training, which only induces a short-term memory (STM), promoted the formation of SOR-long term memory (SOR-LTM) in rats. The effect induced by stress was dependent on the activation of glucocorticoid- and mineralocorticoid-receptors, brain-derived neurotrophic factor (BDNF) and protein synthesis in the dorsal hippocampus. In contrast, EP after a strong SOR impaired SOR-LTM probably by interfering with the use of necessary resources. Moreover, we show that the EP session before training induced anterograde interference, which it was not reversed by a subsequent exposure to an open field. Our findings provide novel insights into the impact of stress on LTM formation in rodents and they are discussed under the behavioral analogue of the synaptic tagging and capture hypothesis.Fil: Lopes Da Cunha, Pamela Johanna. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂ­a Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂ­a Celular y Neurociencia; ArgentinaFil: Villar, MarĂ­a Eugenia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂ­a Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂ­a Celular y Neurociencia; ArgentinaFil: Ballarini, Fabricio Matias. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂ­a Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂ­a Celular y Neurociencia; ArgentinaFil: Tintorelli, Ramiro GastĂłn. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂ­a Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂ­a Celular y Neurociencia; ArgentinaFil: Viola, Haydee Ana Maria. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂ­a Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂ­a Celular y Neurociencia; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentin

    Spatial Object Recommendation with Hints: When Spatial Granularity Matters

    Full text link
    Existing spatial object recommendation algorithms generally treat objects identically when ranking them. However, spatial objects often cover different levels of spatial granularity and thereby are heterogeneous. For example, one user may prefer to be recommended a region (say Manhattan), while another user might prefer a venue (say a restaurant). Even for the same user, preferences can change at different stages of data exploration. In this paper, we study how to support top-k spatial object recommendations at varying levels of spatial granularity, enabling spatial objects at varying granularity, such as a city, suburb, or building, as a Point of Interest (POI). To solve this problem, we propose the use of a POI tree, which captures spatial containment relationships between POIs. We design a novel multi-task learning model called MPR (short for Multi-level POI Recommendation), where each task aims to return the top-k POIs at a certain spatial granularity level. Each task consists of two subtasks: (i) attribute-based representation learning; (ii) interaction-based representation learning. The first subtask learns the feature representations for both users and POIs, capturing attributes directly from their profiles. The second subtask incorporates user-POI interactions into the model. Additionally, MPR can provide insights into why certain recommendations are being made to a user based on three types of hints: user-aspect, POI-aspect, and interaction-aspect. We empirically validate our approach using two real-life datasets, and show promising performance improvements over several state-of-the-art methods

    A multi-scale method to assess pesticide contamination risks in agricultural watersheds

    Get PDF
    The protection of water is now a major priority for environmental managers, especially around drinkingpumping stations. In view of the new challenges facing water agencies, we developed a method designedto support their public policy decision-making, at a variety of different spatial scales. In this paper, wepresent this new spatial method, using remote sensing and a GIS, designed to determine the contami-nation risk due to agricultural inputs, such as pesticides. The originality of this method lies in the useof a very detailed spatial object, the RSO (Reference Spatial Object), which can be aggregated to manyworking and managing scales. This has been achieved thanks to the pixel size of the remote sensing, witha grid resolution of 30 m × 30 m in our application.The method – called PHYTOPIXAL – is based on a combination of indicators relating to the environmen-tal vulnerability of the surface water environment (slope, soil type and distance to the stream) and theagricultural pressure (land use and practices of the farmers). The combination of these indicators for eachpixel provides the contamination risk. The scoring of variables was implemented according knowledgein literature and of experts.This method is used to target specific agricultural input transfer risks. The risk values are first calculatedfor each pixel. After this initial calculation, the data are then aggregated for decision makers, accordingto the most suitable levels of organisation. These data are based on an average value for the watershedareas.In this paper we detail an application of the method to an area in the hills of Southwest France. Weshow the pesticide contamination risk by in areas with different sized watersheds, ranging from 2 km2to 7000 km2, in which stream water is collected for consumption by humans and animals. The resultswere recently used by the regional water agency to determine the protection zoning for a large pumpingstation. Measures were then proposed to farmers with a view to improving their practices.The method can be extrapolated to different other areas to preserve or restore the surface water

    Analysis of Gothic Architectural Details by Spatial Object Reconstruction Techniques

    Get PDF
    The paper focuses on the 3D data acquisition technologiesthat support capturing the geometry of medieval architecturalfragmented stones. High-resolution models of such fragmentsenable the analysis of profile shapes as well as the markinglines and curves left by the instruments of stonemasons, andtherefore, indirectly, identifying connections between severalmaster builders could become possible. Considering therequirements of historical analysis and the fact that the investigatedstones are under monument protection, the authorsdecided to use remote sensing technologies, such as structuredlight scanning, terrestrial laser scanning, depth camera andimage-based reconstruction.The paper evaluates the discussed technologies based on theaccuracy and geometric resolution of the obtained 3D models.Besides technical parameters, time and cost requirements alsohave been investigated. The paper gives an overview on theadvantages and shortcomings of the applied data acquisitiontechnologies and of the provided end-products

    Cyclical Flow: Spatial Synthesis Sound Toy as Multichannel Composition Tool

    Get PDF
    This paper outlines and discusses an interactive system designed as a playful ‘sound toy’ for spatial composition. Proposed models of composition and design in this context are discussed. The design, functionality and application of the software system is then outlined and summarised. The paper concludes with observations from use, and discussion of future developments
    • 

    corecore