967,170 research outputs found

    Inferring Rankings Using Constrained Sensing

    Full text link
    We consider the problem of recovering a function over the space of permutations (or, the symmetric group) over nn elements from given partial information; the partial information we consider is related to the group theoretic Fourier Transform of the function. This problem naturally arises in several settings such as ranked elections, multi-object tracking, ranking systems, and recommendation systems. Inspired by the work of Donoho and Stark in the context of discrete-time functions, we focus on non-negative functions with a sparse support (support size \ll domain size). Our recovery method is based on finding the sparsest solution (through 0\ell_0 optimization) that is consistent with the available information. As the main result, we derive sufficient conditions for functions that can be recovered exactly from partial information through 0\ell_0 optimization. Under a natural random model for the generation of functions, we quantify the recoverability conditions by deriving bounds on the sparsity (support size) for which the function satisfies the sufficient conditions with a high probability as nn \to \infty. 0\ell_0 optimization is computationally hard. Therefore, the popular compressive sensing literature considers solving the convex relaxation, 1\ell_1 optimization, to find the sparsest solution. However, we show that 1\ell_1 optimization fails to recover a function (even with constant sparsity) generated using the random model with a high probability as nn \to \infty. In order to overcome this problem, we propose a novel iterative algorithm for the recovery of functions that satisfy the sufficient conditions. Finally, using an Information Theoretic framework, we study necessary conditions for exact recovery to be possible.Comment: 19 page

    Quality of information in the context of ambient assisted living

    Get PDF
    Série : Advances in Soft Computing, vol. 50With the use of new computational technologies and novel methodologies for problem solving, recurring to the use of Group Decision Support Systems, normally the problem of incomplete information is marginalized as if we were living in an ideal world. Common sense tells us that in the precise time a decision is make it is impossible to know all the information regarding to it, however decisions must be made. What we propose, in the ambit of the VirtualECare project, is a possible solution to decision making, through the use of Group Decision Support Systems, aware of incomplete information but, even so, able to make decisions based in the quality of the information and its source

    Supporting Memorization and Problem Solving with Spatial Information Presentations in Virtual Environments

    Get PDF
    While it has been suggested that immersive virtual environments could provide benefits for educational applications, few studies have formally evaluated how the enhanced perceptual displays of such systems might improve learning. Using simplified memorization and problem-solving tasks as representative approximations of more advanced types of learning, we are investigating the effects of providing supplemental spatial information on the performance of learning-based activities within virtual environments. We performed two experiments to investigate whether users can take advantage of a spatial information presentation to improve performance on cognitive processing activities. In both experiments, information was presented either directly in front of the participant or wrapped around the participant along the walls of a surround display. In our first experiment, we found that the spatial presentation caused better performance on a memorization and recall task. To investigate whether the advantages of spatial information presentation extend beyond memorization to higher level cognitive activities, our second experiment employed a puzzle-like task that required critical thinking using the presented information. The results indicate that no performance improvements or mental workload reductions were gained from the spatial presentation method compared to a non-spatial layout for our problem-solving task. The results of these two experiments suggest that supplemental spatial information can support performance improvements for cognitive processing and learning-based activities, but its effectiveness is dependent on the nature of the task and a meaningful use of space

    A review of GIS-based information sharing systems

    Get PDF
    GIS-based information sharing systems have been implemented in many of England and Wales' Crime and Disorder Reduction Partnerships (CDRPs). The information sharing role of these systems is seen as being vital to help in the review of crime, disorder and misuse of drugs; to sustain strategic objectives, to monitor interventions and initiatives; and support action plans for service delivery. This evaluation into these systems aimed to identify the lessons learned from existing systems, identify how these systems can be best used to support the business functions of CDRPs, identify common weaknesses across the systems, and produce guidelines on how these systems should be further developed. At present there are in excess of 20 major systems distributed across England and Wales. This evaluation considered a representative sample of ten systems. To date, little documented evidence has been collected by the systems that demonstrate the direct impact they are having in reducing crime and disorder, and the misuse of drugs. All point to how they are contributing to more effective partnership working, but all systems must be encouraged to record how they are contributing to improving community safety. Demonstrating this impact will help them to assure their future role in their CDRPs. By reviewing the systems wholly, several key ingredients were identified that were evident in contributing to the effectiveness of these systems. These included the need for an effective partnership business model within which the system operates, and the generation of good quality multi-agency intelligence products from the system. In helping to determine the future development of GIS-based information sharing systems, four key community safety partnership business service functions have been identified that these systems can most effectively support. These functions support the performance review requirements of CDRPs, operate a problem solving scanning and analysis role, and offer an interface with the public. By following these business service functions as a template will provide for a more effective application of these systems nationally

    Determining prerogative by factors of significance, logical or programming controller

    Get PDF
    Advances in information technology design computer systems and networks helped to deepen the study of the processes that can lead to loss of integrity, confidentiality or availability of information or even its destruction. Information technology protect the confidentiality of information in computer systems and networks for the present time by following directions - SDN (software-defined networking) and ACI (Application Centric Infrastructure). Given the trends of information technology and approaches to problem-solving information security important task is to determine the appropriate direction through the use of a decision support system to further improve the selected information technology. Using decision support system conducted experimental verification of analytical model that allows you to answer about the merits of one or another system chosen key measurements and metrics, identify the strengths and weaknesses of the systems that will allow for further development and open up new opportunities

    The innovation of Multiview3 for development professionals

    Get PDF
    The Multiview Methodology for Information Systems Development has never been a widely used or mass-market approach. It has always had a small user base, a localised approach to a global issue: coherent IS development. This paper concerns the underreported innovation of the Multiview3 methodology for Information systems analysis, design and development – specifically designed for non-specialists working in developing countries. The innovation emerged from the identification of a methodological ‘gap’ in support for non-specialists struggling with Information Systems problem structuring challenges. The Multiview3 story tells us how IS methodology can be innovated to address the needs of users. This version of Multiview is argued to be theoretically distinct from previous versions in terms of its focus (developing countries) and application (problem solving and co-learning in practice)

    Determining prerogative by factors of significance, logical or programming controller

    Get PDF
    Advances in information technology design computer systems and networks helped to deepen the study of the processes that can lead to loss of integrity, confidentiality or availability of information or even its destruction. Information technology protect the confidentiality of information in computer systems and networks for the present time by following directions - SDN (software-defined networking) and ACI (Application Centric Infrastructure). Given the trends of information technology and approaches to problem-solving information security important task is to determine the appropriate direction through the use of a decision support system to further improve the selected information technology. Using decision support system conducted experimental verification of analytical model that allows you to answer about the merits of one or another system chosen key measurements and metrics, identify the strengths and weaknesses of the systems that will allow for further development and open up new opportunities

    Testing an Integrity-Checking DSS Component for Organizational Memory Building

    Get PDF
    Organizational Memory (OM) has become a critical component of organizations attempting to maintain a competitive advantage. The ability to retrieve accurate information, and interpret it from different perspectives, will both facilitate efficient problem solving and support efficient organizational learning. This research examines the effect of an informationbuilding and decision aid. The results indicate that the system positively affects OM by promoting user-entered knowledge bases with more accurate statements. However, the system did not significantly improve the ability of the users to solve a problem. These findings have important implications for designing information systems to support and expand OM while increasing the organization’s capacity to learn and solve problems
    corecore