128 research outputs found

    Towards a standard design language for AOSD

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    Decentralized Coordination of Dynamic Software Updates in the Internet of Things

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    Large scale IoT service deployments run on a high number of distributed, interconnected computing nodes comprising sensors, actuators, gateways and cloud infrastructure. Since IoT is a fast growing, dynamic domain, the implementation of software components are subject to frequent changes addressing bug fixes, quality insurance or changed requirements. To ensure the continuous monitoring and control of processes, software updates have to be conducted while the nodes are operating without losing any sensed data or actuator instructions. Current IoT solutions usually support the centralized management and automated deployment of updates but are restricted to broadcasting the updates and local update processes at all nodes. In this paper we propose an update mechanism for IoT deployments that considers dependencies between services across multiple nodes involved in a common service and supports a coordinated update of component instances on distributed nodes. We rely on LyRT on all IoT nodes as the runtime supporting local disruption-minimal software updates. Our proposed middleware layer coordinates updates on a set of distributed nodes. We evaluated our approach using a demand response scenario from the smart grid domain

    Context-dependent reconfiguration of autonomous vehicles in mixed traffic

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    Human drivers naturally adapt their behaviour depending on the traffic conditions, such as the current weather and road type. Autonomous vehicles need to do the same, in a way that is both safe and efficient in traffic composed of both conventional and autonomous vehicles. In this paper, we demonstrate the applicability of a reconfigurable vehicle controller agent for autonomous vehicles that adapts the parameters of a used car-following model at runtime, so as to maintain a high degree of traffic quality (efficiency and safety) under different weather conditions.We follow a dynamic software product line approach to model the variability of the car-following model parameters, context changes and traffic quality, and generate specific configurations for each particular context. Under realistic conditions, autonomous vehicles have only a very local knowledge of other vehicles' variables.We investigate a distributed model predictive controller agent for autonomous vehicles to estimate their behavioural parameters at runtime, based on their available knowledge of the system.We show that autonomous vehicles with the proposed reconfigurable controller agent lead to behaviour similar to that achieved by human drivers, depending on the context.Junta de Andalucía MAGIC P12-TIC1814Ministerio de Ciencia, Innovación y Universidades HADAS TIN2015-64841-

    Isotopic and microbotanical insights into Iron Age agricultural reliance in the Central African rainforest

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    The emergence of agriculture in Central Africa has previously been associated with the migration of Bantu-speaking populations during an anthropogenic or climate-driven ‘opening’ of the rainforest. However, such models are based on assumptions of environmental requirements of key crops (e.g. Pennisetum glaucum) and direct insights into human dietary reliance remain absent. Here, we utilise stable isotope analysis (δ13C, δ15N, δ18O) of human and animal remains and charred food remains, as well as plant microparticles from dental calculus, to assess the importance of incoming crops in the Congo Basin. Our data, spanning the early Iron Age to recent history, reveals variation in the adoption of cereals, with a persistent focus on forest and freshwater resources in some areas. These data provide new dietary evidence and document the longevity of mosaic subsistence strategies in the region

    Helping Babies Breathe in Sudan

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    A hospital-to-hospital partnership between Cork and Sudan aims to reduce neonatal deaths in Sudan by focusing on training village midwives in neonatal resuscitation techniques

    Hunter-gatherer environments at the Late Pleistocene sites of Mwanganda's Village and Bruce, northern Malawi

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    Mwanganda's Village (MGD) and Bruce (BRU) are two open-air site complexes in northern Malawi with deposits dating to between 15 and 58 thousand years ago (ka) and containing Middle Stone Age (MSA) lithic assemblages. The sites have been known since 1966 and 1965, respectively, but lacked chronometric and site formation data necessary for their interpretation. The area hosts a rich stone artifact record, eroding from and found within alluvial fan deposits exhibiting poor preservation of organic materials. Although this generally limits opportunities for site-based environmental reconstructions, MGD and BRU are located at the distal margins of the alluvial fan, where lacustrine lagoonal deposits were overprinted by a calcrete paleosol. This has created locally improved organic preservation and allowed us to obtain ecological data from pollen, phytoliths, and pedogenic carbonates, producing a regional- to site-scale environmental context for periods of site use and abandonment. Here, we integrate the ecological data into a detailed site formation history, based on field observations and micromorphology, supplemented by cathodoluminescence microscopy and μ-XRF. By comparing local, on-site environmental proxies with more regional indicators, we can better evaluate how MSA hunter-gatherers made decisions about the use of resources across the landscape. Our data indicate that while tree cover similar to modern miombo woodland and evergreen gallery forest prevailed at most times, MSA hunter-gatherers chose more locally open environments for activities that resulted in a lithic artifact record at multiple locations between 51 and 15 ka.publishedVersio

    The feasibility of a Comprehensive Resilience-building psychosocial Intervention (CREST) for people with dementia in the community: protocol for a non-randomised feasibility study

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    Background: A dementia diagnosis can prevent people from participating in society, leading to a further decline in cognitive, social and physical health. However, it may be possible for people with dementia to continue to live meaningful lives and continue to participate actively in society if a supportive psychosocial environment exists. Resilience theory, which focuses on strengthening personal attributes and external assets in the face of serious challenges, may provide a scaffold on which an inclusive multifaceted psychosocial supportive environment can be built. This protocol paper describes a study to determine the feasibility of conducting a multifaceted complex resilience building psychosocial intervention for people with dementia and their caregivers living in the community. Methods: This is a non-randomised feasibility study. Ten participants with dementia and their primary caregivers living in the community will be recruited and receive the CREST intervention. The intervention provides (a) a 7-week cognitive stimulation programme followed by an 8-week physical exercise programme for people with dementia and (b) a 6-week educational programme for caregivers. Members of the wider community will be invited to a dementia awareness programme and GP practices to a dementia training workshop. Trained professionals will deliver all intervention components. Outcomes will assess the feasibility and acceptability of all study processes. The feasibility and acceptability of a range of outcomes to be collected in a future definitive trial, including economic measurements, will also be explored. Finally, social marketing will be used to map a route toward stigma change in dementia for use in a subsequent trial. Quantitative feasibility outcome assessments will be completed at baseline and after completion of the 15-week intervention while qualitative data will be collected at recruitment, baseline, during and post-intervention delivery. Conclusion: This feasibility study will provide evidence regarding the feasibility and acceptability of a comprehensive multifaceted psychosocial intervention programme for people with dementia and their caregivers (CREST). The results will be used to inform the development and implementation of a subsequent RCT, should the findings support feasibility

    The feasibility of a comprehensive resilience-building psychosocial Intervention (CREST) for people with dementia in the community: protocol for a non-randomised feasibility study

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    Background: A dementia diagnosis can prevent people from participating in society, leading to a further decline in cognitive, social and physical health. However, it may be possible for people with dementia to continue to live meaningful lives and continue to participate actively in society if a supportive psychosocial environment exists. Resilience theory, which focuses on strengthening personal attributes and external assets in the face of serious challenges, may provide a scaffold on which an inclusive multifaceted psychosocial supportive environment can be built. This protocol paper describes a study to determine the feasibility of conducting a multifaceted complex resilience building psychosocial intervention for people with dementia and their caregivers living in the community. Methods: This is a non-randomised feasibility study. Ten participants with dementia and their primary caregivers living in the community will be recruited and receive the CREST intervention. The intervention provides (a) a 7-week cognitive stimulation programme followed by an 8-week physical exercise programme for people with dementia and (b) a 6-week educational programme for caregivers. Members of the wider community will be invited to a dementia awareness programme and GP practices to a dementia training workshop. Trained professionals will deliver all intervention components. Outcomes will assess the feasibility and acceptability of all study processes. The feasibility and acceptability of a range of outcomes to be collected in a future definitive trial, including economic measurements, will also be explored. Finally, social marketing will be used to map a route toward stigma change in dementia for use in a subsequent trial. Quantitative feasibility outcome assessments will be completed at baseline and after completion of the 15-week intervention while qualitative data will be collected at recruitment, baseline, during and post-intervention delivery Conclusion: This feasibility study will provide evidence regarding the feasibility and acceptability of a comprehensive multifaceted psychosocial intervention programme for people with dementia and their caregivers (CREST). The results will be used to inform the development and implementation of a subsequent RCT, should the findings support feasibility. Trial registration: ISRCTN25294519 Retrospectively registered 07.10.201

    Building a refinement checker for Z

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    In previous work we have described how refinements can be checked using a temporal logic based model-checker, and how we have built a model-checker for Z by providing a translation of Z into the SAL input language. In this paper we draw these two strands of work together and discuss how we have implemented refinement checking in our Z2SAL toolset. The net effect of this work is that the SAL toolset can be used to check refinements between Z specifications supplied as input files written in the LaTeX mark-up. Two examples are used to illustrate the approach and compare it with a manual translation and refinement check.Comment: In Proceedings Refine 2011, arXiv:1106.348

    Extending standard UML with model composition semantics

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    There is a well documented problem in the software engineering field relating to a structural mismatch between the specification of requirements for software systems and the specification of object-oriented software systems. The structural mismatch happens because the units of interest during the requirements phase (for example, feature, service, capability, function etc.) are different to the units of interest during object-oriented design and implementation (for example, object, class, method, etc.). The structural mismatch results in support for a single requirement being scattered across the design units and a single design unit supporting multiple requirements -- this in turn results in reduced comprehensibility, traceability and reuse of design models
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