1,543 research outputs found

    Strong, Weak and Branching Bisimulation for Transition Systems and Markov Reward Chains: A Unifying Matrix Approach

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    We first study labeled transition systems with explicit successful termination. We establish the notions of strong, weak, and branching bisimulation in terms of boolean matrix theory, introducing thus a novel and powerful algebraic apparatus. Next we consider Markov reward chains which are standardly presented in real matrix theory. By interpreting the obtained matrix conditions for bisimulations in this setting, we automatically obtain the definitions of strong, weak, and branching bisimulation for Markov reward chains. The obtained strong and weak bisimulations are shown to coincide with some existing notions, while the obtained branching bisimulation is new, but its usefulness is questionable

    Privacy challenges in third-party location services

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    The concern for location privacy in mobile applications is commonly motivated by a scenario in which a mobile device communicates personal location data, i.e. the device holder location, to a third party e.g. LBS provider, in exchange for some information service. We argue that this scenario offers a partial view of the actual risks for privacy, because in reality the information How can be more complex. For example, more and more often location is computed by a third party, the location provider, e.g. Google Location Service. Location providers are in the position of collecting huge amounts of location data from the users of diverse applications (e.g. Facebook and Foursquare to cite a few). This raises novel privacy concerns. In this paper, we discuss two issues related to the protection from location providers. The first focuses on the compliance of emerging location services standards with European data protection norms; the latter focuses on hard privacy solutions protecting from untrusted location providers

    Privacy-aware geolocation interfaces for volunteered geography : a case study

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    The standard W3C Geolocation API can signi cantly facilitate geospatial data collection as it provides a simple set of operations for requesting geolocation services across indoor and outdoor spaces through the Web. Importantly, this API is privacy-aware in that it provides a basic privacy mechanism for requesting the user's consent to location acquisition. In this paper we address the question on whether this privacy mechanism is su cient to conduct a project for the collection of geospatial content, in compliance with privacy laws. The question is of practical relevance as the use of geolocation standards in line with privacy regulations would make the development of volunteered geography projects easier. In this paper we present an interdisciplinary analysis spanning across technology and law, and driven by an application case. We show the limitations of this API and discuss a possible extension in line with privacy norms. Although we con ne ourselves to consider European regulations, we believe that this study can be of more general concern

    Making video communication mobile by using a small humanoid social assistive robot

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    There is a high need among older persons to maintain their social contacts and to stay involved in social life. In this area of social communication ICT and assistive technology can bring a significant support provided that the actual needs and preferences of the user groups are actually met. The paper describes an innovative solution consisting of a mobile video communication facility using a LED projector which is integrated in a social assistive robot system developed in the framework of the KSERA project

    Making video communication mobile by using a small humanoid social assistive robot

    Get PDF
    There is a high need among older persons to maintain their social contacts and to stay involved in social life. In this area of social communication ICT and assistive technology can bring a significant support provided that the actual needs and preferences of the user groups are actually met. The paper describes an innovative solution consisting of a mobile video communication facility using a LED projector which is integrated in a social assistive robot system developed in the framework of the KSERA project

    More treatment but no less depression:The treatment-prevalence paradox

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    Treatments for depression have improved, and their availability has markedly increased since the 1980s. Mysteriously the general population prevalence of depression has not decreased. This "treatment-prevalence paradox" (TPP) raises fundamental questions about the diagnosis and treatment of depression. We propose and evaluate seven explanations for the TPP. First, two explanations assume that improved and more widely available treatments have reduced prevalence, but that the reduction has been offset by an increase in: 1) misdiagnosing distress as depression, yielding more "false positive" diagnoses; or 2) an actual increase in depression incidence. Second, the remaining five explanations assume prevalence has not decreased, but suggest that: 3) treatments are less efficacious and 4) less enduring than the literature suggests; 5) trial efficacy doesn't generalize to real-world settings; 6) population-level treatment impact differs for chronic-recurrent versus non-recurrent cases; and 7) treatments have some iatrogenic consequences. Any of these seven explanations could undermine treatment impact on prevalence, thereby helping to explain the TPP. Our analysis reveals that there is little evidence that incidence or prevalence have increased as a result of error or fact (Explanations 1 and 2), and strong evidence that (a) the published literature overestimates short- and long-term treatment efficacy, (b) treatments are considerably less effective as deployed in "real world" settings, and (c) treatment impact differs substantially for chronic-recurrent cases relative to non-recurrent cases. Collectively, these a-c explanations likely account for most of the TPP. Lastly, little research exists on iatrogenic effects of current treatments (Explanation 7), but further exploration is critical

    Linearization of CIF Through SOS

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    Linearization is the procedure of rewriting a process term into a linear form, which consist only of basic operators of the process language. This procedure is interesting both from a theoretical and a practical point of view. In particular, a linearization algorithm is needed for the Compositional Interchange Format (CIF), an automaton based modeling language. The problem of devising efficient linearization algorithms is not trivial, and has been already addressed in literature. However, the linearization algorithms obtained are the result of an inventive process, and the proof of correctness comes as an afterthought. Furthermore, the semantic specification of the language does not play an important role on the design of the algorithm. In this work we present a method for obtaining an efficient linearization algorithm, through a step-wise refinement of the SOS rules of CIF. As a result, we show how the semantic specification of the language can guide the implementation of such a procedure, yielding a simple proof of correctness.Comment: In Proceedings EXPRESS 2011, arXiv:1108.407

    Viewpoint: WHO world mental health surveys international college student initiative: implementation issues in low‐ and middle‐income countries

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    The university system and students are rapidly growing and changing in low‐ and middle‐income countries (LMICs). This growth can facilitate enhanced national productivity yet it can also bring potential risks to student mental health. The World Mental Health Surveys International College Student (WMH‐ICS) initiative could increase information and support in a relatively low‐cost manner for university students in LMICs—a group that is particularly vulnerable to mental health problems and who live in an environment where few targeted resources may be available. Effective implementation of the WMH‐ICS initiative, however, requires long‐term planning and consideration of the specific challenges present in LMIC settings. Planning as to what types of interventions would be needed and achievable in the next 10 to 15 years and consideration of local issues related to uptake, acceptability, appropriateness, feasibility, fidelity, and sustainability from the very beginning would be needed to ensure that the initiative would be useful in the future
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