136 research outputs found

    Learning by doing on the EGEE GRID and first performance analysis of CODESA-3D multirun submission

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    The project TEMA (Training on Environmental Modelling and Applications) is a CRS4 training initiative in the field of computational hydrology and grid computing (Jan-Sept, 2006). The personnel involved were Fabrizio Murgia (trainee) and Giuditta Lecca (tutor). The objectives of the project were: " To aquire specialized skills about grid computing with special emphasis on computational sub-surface hydrology; " To develop and test software procedures to run Monte Carlo simulations on the EGEE production grid; " To produce a technical report and some seminars about grid computing. The aquired competences and skills will be used in the ongoing projects GRIDA3, CyberSAR and DEGREE

    Open CASCADE and rapid prototyping in human carotid lumen reconstruction

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    Image processing algorithms, CAD-CAM tools and rapid prototyping (RP) techniques are able to produce complex lumen artery replicas. This work presents a system for manufacturing the lumen of human carotid from computed tomography acquisition. The pipe-line of manufacturing process of a human carotid lumen replication is presented. Each stage of the pipe-line is briefly discussed. Technical details of the 3D surface reconstruction phase, based on the Open Cascade geometric modelling software, and the RP manufaturing process based on Fused Deposition Modelling are presented

    Audio-based interventions in sport

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    In common practice, sports-perceptual interventions are mainly based on vision. However, research demonstrates that sporting performance can also be improved through the use of sounds, showing the relevance of the auditory channel to convey sports-related information, which can positively affect athletes\u2019 motor outcomes. This review examines the potential of audio-based interventions in sport. The relevant concepts are defined, a brief overview of the techniques based on vision is given and laboratory studies demonstrating the effectiveness of sounds in improving the execution of simple rhythmic motor tasks are reviewed. Subsequently, neurophysiological evidence of the influence of sounds on the motor regions of the brain is provided and different kinds of audio-based interventions, emphasising their methodological details and the effects of their application to specific sporting performances are described. Finally, recommendations for further research in this field, aimed both at maximizing the potential of audio-based interventions and their implementation at applied sporting contexts, are suggested

    A complete season with attendance restrictions confirms the relevant contribution of spectators to home advantage and referee bias in association football

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    Due to the unfortunate pandemic situation, the phenomena of home advantage and referee bias in sports have recently received a particular research attention, especially in association football. In this regard, several studies were conducted on the last portion of the 2019-20 season: the majority of them suggests a reduction-but not the elimination-of the two phenomena, with some exceptions in which no reduction was found or, at the other extreme, the phenomena were not observed at all

    Anatomical shape reconstruction and manufacturing: solving topological changes of lumen vessel trough geometric approach

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    Over the last years there has been an increasing growth of interest in Rapid Prototyping (RP) techniques applied to various fields of medicine. RP makes it possible, in vascular surgery, to produce accurate anatomic replicas of patient vessels. These replicas can help the customization of surgical invasive interventions such as in situ stent-graft insertion in carotid region. The main goal of this work is to obtain high quality in lumen reconstruction and manufacturing replicas by RP technique. This goal is achieved through the complete control of each phase of the generating process. We present a semi-automatic method for carotid lumen reconstruction based on Boundary Representation (BRep). All parameters influencing the quality of the shape reconstruction are presented and discussed: shape acquisition, shape reconstruction and shape manufacturing. The shape acquisition starts by extracting the points belonging to the boundary of the lumen vessel, from Computer Tomography (CT) images. These points, parameterised in a vector, are the input data of the shape reconstruction algorithm based on B-Spline interpolation. The B-Spline type for representing curves and surfaces were chosen because of their properties of continuity and local control. In the shape reconstruction stage we had to face problems due to the topological change on the vessel structure. For vessel regions where there are not changes of topology, we use the closed B-Spline curves (belonging to adjacent acquisition planes) as generating curves to build a B-Spline surface. For vessel regions with at least a change of topology (ex. bifurcation region) our algorithm split automatically the involved curves to obtain three rectangular B-Spline patches. Such patches are joined together to obtain the bifurcation vessel lumen. The set of lumen surfaces is then inserted in a Boundary Representation in order to get a valid solid. To analyse the quality of the reconstructed shapes, the final object is compared with the acquisition image. This solid is correctly tessellated in triangles to produce the data format used by the RP devices (STL)

    Contrasting a Misinterpretation of the Reverse Contrast

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    open access articleThe reverse contrast is a perceptual phenomenon in which the effect of the classical simultaneous lightness contrast is reversed. In classic simultaneous lightness contrast configurations, a gray surrounded by black is perceived lighter than an identical gray surrounded by white, but in the reverse contrast configurations, the perceptual outcome is the opposite: a gray surrounded by black appears darker than the same gray surrounded by white. The explanation provided for the reverse contrast (by different authors) is the belongingness of the gray targets to a more complex configuration. Different configurations show the occurrence of these phenomena; however, the factors determining this effect are not always the same. In particular, some configurations are based on both belongingness and assimilation, while one configuration is based only on belongingness. The evidence that different factors determine the reverse contrast is crucial for future research dealing with achromatic color perception and, in particular, with lightness induction phenomena

    Walking and encoding heading bias

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI linkPrevious studies demonstrated that physical movement enhanced spatial updating in described environments. However, those movements were executed only after the encoding of the environment, minimally affecting the development of the spatial representation. Thus, we investigated whether and how participants could benefit from the execution of physical movement during the encoding of described environments, in terms of enhanced spatial updating. Using the judgement of relative directions task, we compared the effects of walking both during and after the description of the environment, and walking only after the description on spatial updating. Spatial updating was evaluated in terms of accuracy and response times in different headings. We found that the distribution of response times across Headings seemed not to be related to the physical movement executed, whereas the distribution of accuracy scores seemed to significantly change with the action executed. Indeed, when no movement occurred during the encoding of the environment, a preference for the learning heading was found, which did not emerge when walking during encoding occurred. Therefore, the results seem to suggest that physical movement during encoding supports the development of a heading-independent representation of described environments, reducing the anchoring for a preferred heading in favor of a global representation

    Perception and Action in Complex Movements: The Emerging Relevance of Auditory Information

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    Recent studies explored the contribution of auditory information in ecological contexts to biological motion perception and its influence on movement execution. This work provides an overview of the most influential scientific contributions in this domain and analyzes the most recent findings, both in sport and motor rehabilitation. Overall, the literature indicates that ecological sounds associated with movements are relevant for perceiving some important features of sport movements. Auditory information is also relevant during performance execution, and can be used to create training protocols. Also, similarly auditory information can be used in clinical contexts to provide rhythmic information to enhance the efficacy of motor rehabilitation protocols. In conclusion, we can say that the role of ecological sounds of movements is examined in conveying complexity of information from a gestalt perspective

    AQUAGRID: an extensible platform for collaborative problem solving in groundwater protection

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    AQUAGRID is the subsurface hydrology computational service of the Sardinian GRIDA3 infrastructure, designed to deliver complex environmental applications via a user-friendly Web portal. The service aims to provide to water professionals integrated modeling tools to solve water resources management problems and aid decision making for contaminated soil and groundwater. In this paper, the AQUAGRID application concept and enabling technologies are illustrated. At the heart of the service are the computational models to simulate complex and large groundwater flow and contaminant transport problems and geochemical speciation. AQUAGRID is built on top of compute-Grid technologies by means of the EnginFrame Grid framework. Distributed data management is provided by the Storage Resource Broker data-Grid middleware. The resulting environment allows end-users to perform groundwater simulations and to visualize and interact with their results, using graphs, 3D images and annotated maps. The problem solving capability of the platform is demonstrated using the results of two case studies deployed
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