233 research outputs found

    Efficient and Generalized Decentralized Monitoring of Regular Languages

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    Part 2: Monitoring and TestingInternational audienceThis paper proposes an efficient and generalized decentralized monitoring algorithm allowing to detect satisfaction or violation of any regular specification by local monitors alone in a system without central observation point. Our algorithm does not assume any form of synchronization between system events and communication of monitors, uses state machines as underlying mechanism for efficiency, and tries to keep the number and size of messages exchanged between monitors to a minimum. We provide a full implementation of the algorithm with an open-source benchmark to evaluate its efficiency in terms of number, size of exchanged messages, and delay induced by communication between monitors. Experimental results demonstrate the effectiveness of our algorithm which outperforms the previous most general one along several (new) monitoring metrics

    Randomisation and Derandomisation in Descriptive Complexity Theory

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    We study probabilistic complexity classes and questions of derandomisation from a logical point of view. For each logic L we introduce a new logic BPL, bounded error probabilistic L, which is defined from L in a similar way as the complexity class BPP, bounded error probabilistic polynomial time, is defined from PTIME. Our main focus lies on questions of derandomisation, and we prove that there is a query which is definable in BPFO, the probabilistic version of first-order logic, but not in Cinf, finite variable infinitary logic with counting. This implies that many of the standard logics of finite model theory, like transitive closure logic and fixed-point logic, both with and without counting, cannot be derandomised. Similarly, we present a query on ordered structures which is definable in BPFO but not in monadic second-order logic, and a query on additive structures which is definable in BPFO but not in FO. The latter of these queries shows that certain uniform variants of AC0 (bounded-depth polynomial sized circuits) cannot be derandomised. These results are in contrast to the general belief that most standard complexity classes can be derandomised. Finally, we note that BPIFP+C, the probabilistic version of fixed-point logic with counting, captures the complexity class BPP, even on unordered structures

    Research challenges in evaluating gender-based violence response services in a refugee camp

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    This article presents a case study of research in Dadaab, Kenya to highlight some of the relevant challenges encountered while conducting gender-based violence research in humanitarian settings. A longitudinal mixed-methods design was used to evaluate a comprehensive case-management intervention in the refugee complex near the border of Kenya and Somalia. We present an overview of both expected and unexpected challenges during preparation and implementation of the research, adaptations made to the research design, and lessons learned for future research in similar contexts. Some of the key challenges were attributed to the highly securitized and remote environment of Dadaab refugee camp, like many refugee camp settings, which created limitations for sampling designs, interview locations, and also created particular burdens for the research team members conducting interviews. In addition to the camp environment, the dynamic nature of events and trends in the camp setting created barriers to follow-up with longitudinal cohort participants as well as uncertainty on how to plan for future implementation of research design phases in response to camp changes. Conducting research in humanitarian settings requires a flexible approach to accommodate the challenges that can impact both service delivery and research activities. The discussion presented in this article contributes to the evolving practical guidance on conducting research in humanitarian settings

    Sustainability and procurement practices in higher education institutions: Barriers and drivers

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    © 2019 A review of the literature reveals the scant research on sustainable procurement in the public sector, and in particular higher education institutions (HEIs). In this context, this paper aims to contribute to an emerging stream of research on drivers and challenges which higher education institutions and the extent to which they are endorsing sustainable procurement practices. The study is based on a survey of HEIs around the world, drawn from a network of sustainability practitioners and researchers at these institutions. Design of the survey drew on existing studies of barriers and enablers, the use of vignettes to provoke ideas among the research team, and a pilot study. Crucially, the study seeks to shed light on both drivers and critical barriers affecting the implementation of sustainable procurement at universities. The results and discussion identify previously unidentified barriers and enablers, and further suggest that smaller HEI have some catching up to do. Policy recommendations are presented and approaches on how to overcome barriers to sustainable procurement are set forth. These centre on the proposal that HEIs should consider developing a reflexive strategy to procurement purchasing policy, and to ensure there are suitable means for its implementation

    Interpreting an action from what we perceive and what we expect

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    International audienceIn update logic as studied by Baltag, Moss, Solecki and van Benthem, little attention is paid to the interpretation of an action by an agent, which is just assumed to depend on the situation. This is actually a complex issue that nevertheless complies to some logical dynamics. In this paper, we tackle this topic. We also deal with actions that change propositional facts of the situation. In parallel, we propose a formalism to accurately represent an agent's epistemic state based on hyperreal numbers. In that respect, we use infinitesimals to express what would surprise the agents (and by how much) by contradicting their beliefs. We also use a subjective probability to model the notion of belief. It turns out that our probabilistic update mechanism satisfies the AGM postulates of belief revision

    Disability, violence, and mental health among Somali refugee women in a humanitarian setting

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    Background There is limited evidence on the relationship between disability, experiences of gender-based violence (GBV), and mental health among refugee women in humanitarian contexts. Methods A cross-sectional analysis was conducted of baseline data (n = 209) collected from women enrolled in a cohort study of refugee women accessing GBV response services in the Dadaab refugee camps in Kenya. Women were surveyed about GBV experiences (past 12 months, before the last 12 months, before arriving in the refugee camps), functional disability status, and mental health (anxiety, depression, post-traumatic stress), and we explored the inter-relationship of these factors. Results Among women accessing GBV response services, 44% reported a disability. A higher proportion of women with a disability (69%) reported a past-year experience of physical intimate partner violence and/or physical or sexual non-partner violence, compared to women without a disability (54%). A higher proportion of women with a disability (32%) experienced non-partner physical or sexual violence before arriving in the camp compared to women without a disability (16%). Disability was associated with higher scores for depression (1.93, 95% confidence interval (CI) 0.54–3.33), PTSD (2.26, 95% CI 0.03–4.49), and anxiety (1.54, 95% CI 0.13–2.95) after adjusting for age, length of encampment, partner status, number of children, and GBV indicators. Conclusions A large proportion of refugee women seeking GBV response services have disabilities, and refugee women with a disability are at high risk of poor mental health. This research highlights the need for mental health and disability screening within GBV response programming

    The impacts of the early outset of the COVID-19 pandemic on climate change research: implications for policy-making

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    Since January 2020, the COVID-19 pandemic has dominated the media and exercises pressure on governments worldwide. Apart from its effects on economies, education systems and societies, the pandemic has also influenced climate change research. This paper examines the extent to which COVID-19 has influenced climate change research worldwide during the first wave at the beginning of 2020 and how it is perceived to exploit it in the future. This study utilised an international survey involving those dedicated to climate change science and management research from Academia, Government, NGOs, and international agencies in 83 countries. The analysis of responses encompasses four independent variables: Institutions, Regions, Scientific Areas, and the level of economic development represented by the Human Development Index (HDI). Results show that: (1) COVID-19 modified the way the surveyed researchers work, (2) there are indicators that COVID-19 has already influenced the direction of climate change and adaptation policy implementation, and (3) respondents perceived (explicitly concerning the COVID-19 lockdowns of March-April 2020), that the pandemic has drawn attention away from climate policy. COVID- 19 has influenced the agenda of climate change research for more than half of the respondents and is likely to continue in the future, suggesting that the impacts on their research will still be felt for many years. The paper concludes by outlining critical implications for policy-making

    Experiences of being exposed to intimate partner violence during pregnancy

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    In this study a phenomenological approach was used in order to enter deeply into the experience of living with violence during pregnancy. The aim of the study was to gain a deeper understanding of women's experiences of being exposed to intimate partner violence (IPV) during pregnancy. The data were collected through in-depth interviews with five Norwegian women; two during pregnancy and three after the birth. The women were between the age of 20 and 38 years. All women had received support from a professional research and treatment centre. The essential structure shows that IPV during pregnancy is characterized by difficult existential choices related to ambivalence. Existential choices mean questioning one's existence, the meaning of life as well as one's responsibility for oneself and others. Five constituents further explain the essential structure: Living in unpredictability, the violence is living in the body, losing oneself, feeling lonely and being pregnant leads to change. Future life with the child is experienced as a possibility for existential change. It is important for health professionals to recognize and support pregnant women who are exposed to violence as well as treating their bodies with care and respect
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