1,258 research outputs found

    Dynamic maps for supporting spatial decision processes

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    The research here described aims at supporting decision making processes related to large scale and long term spatial questions. It proposes a method for sharing information and conveying reasoning by the use of dynamic maps. Through the visual localization of costs and benefits, the participants to the spatial decision processes are led to evaluate methods and objectives for a lot of alternative development options. The system has been used in different case studies showing its effectiveness in creating awareness on spatial problems and enabling discussions

    Visualising accessibility: an interactive tool and two applications to empirical case studies of urban development and public engagement

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    While a substantial body of literature exists on the theoretical definitions and measures of accessibility, the extent to which such measures are applied into practice to assess project alternatives is less frequent (Geurs and Van Wee, 2004). Recent studies affirm that one of the main barriers to the usability of accessibility measure is the lack of visualisation quality and mapping tool for accessibility representation (te Brömmelstroet et al, 2014), while visualisation tools are commonly recognised as the most effective methodology to facilitate knowledge sharing, particularly in those processes involving public stakeholders and non-experts with different expertise. Starting form this consideration, this paper presents an application of the Interactive Visualisation Tool, named InViTo (Pensa and Masala, 2014a; 2014b; Pensa, et al., 2014; Pensa, Masala and Lami, 2013; Pensa, Masala and Marina, 2013) able to generate maps of the level of perceived accessibility (i.e. “desirability”) of different urban areas. Desirability is here computed as the perceived level of access to different urban items as transport supply (metro and rail stations, public transport stops, parking) and urban activities such as hospitals, schools, museums. In this respect, the concept of desirability encompasses a measure of accessibility to several urban facilities, and the perception that residents of the study area have of such facilities. The InViTo tool allows to build up maps of desirability interactively, by making selection of the chosen items and by giving differential weights to each items. This makes the tools powerful and very useful particularly when discussing and showing analysis results to stakeholders, who could have the opportunity to see in real time the results of different scenario alternatives and assumptions. In the paper two applications are presented. The first one to the empirical case study of Rome, presents the steps to undertake in order to apply the tool: from data gathering, maps coding, and results representation. The second application aims at exploring the potential usability of the tool in engaging public stakeholders into the assessment of different urban development options. Furthermore, the results of a workshop held in Turin, in which public and private stakeholders were interactively involved, are discussed. The paper is organised as follows. In section 2, an overview of the InViTo tool is given with a focus on its applicability formeasuring accessibility. In section 3 the results of the two InViTo applications are discussed. Conclusions are drawn in section 4, with an outlook to undergoing research issues

    GPCALMA: a Grid Approach to Mammographic Screening

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    The next generation of High Energy Physics experiments requires a GRID approach to a distributed computing system and the associated data management: the key concept is the "Virtual Organisation" (VO), a group of geographycally distributed users with a common goal and the will to share their resources. A similar approach is being applied to a group of Hospitals which joined the GPCALMA project (Grid Platform for Computer Assisted Library for MAmmography), which will allow common screening programs for early diagnosis of breast and, in the future, lung cancer. HEP techniques come into play in writing the application code, which makes use of neural networks for the image analysis and shows performances similar to radiologists in the diagnosis. GRID technologies will allow remote image analysis and interactive online diagnosis, with a relevant reduction of the delays presently associated to screening programs.Comment: 4 pages, 3 figures; to appear in the Proceedings of Frontier Detectors For Frontier Physics, 9th Pisa Meeting on Advanced Detectors, 25-31 May 2003, La Biodola, Isola d'Elba, Ital

    High-Quality Symmetric Wyner–Ziv Coding Scheme for Low-Motion Videos

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    Traditional Wyner-Ziv video coding (WZVC) structures require either intra (Key) or Wyner-Ziv (WZ) coding of frames. Unfortunately, keeping the video quality approximately constant implies drastic bit-rate fluctuations because consecutive frames of different types (Key or WZ) present significantly different compression performances. Moreover, certain scenarios severely limit rate fluctuation. This work proposes a WZVC scheme with low bit-rate fluctuations based on a symmetric coding structure. First, this work investigates the performance of a generic nonasymmetric distributed source coding structure, showing that the low-density parity-check accumulate channel decoding method is best suited. This is used as a basis to design a symmetric WZVC scheme in which every input video frame is divided into four parallel subframes through subsampling, and then the subframes are encoded by using a symmetric method. Compared with the traditional asymmetric WZVC scheme, the proposed scheme can achieve higher bit-rate stability over time, which is a great advantage to guarantee a reliable transmission in many wireless communication application environments in which bit-rate fluctuations are strongly constrained. Simulation results show the effectiveness of the proposed symmetric WZVC scheme in maintaining a steady bit rate and quality, as well as a quality comparison with the traditional WZVC scheme
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