996 resultados para Execution context


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There has been much interest in the belief–desire–intention (BDI) agent-based model for developing scalable intelligent systems, e.g. using the AgentSpeak framework. However, reasoning from sensor information in these large-scale systems remains a significant challenge. For example, agents may be faced with information from heterogeneous sources which is uncertain and incomplete, while the sources themselves may be unreliable or conflicting. In order to derive meaningful conclusions, it is important that such information be correctly modelled and combined. In this paper, we choose to model uncertain sensor information in Dempster–Shafer (DS) theory. Unfortunately, as in other uncertainty theories, simple combination strategies in DS theory are often too restrictive (losing valuable information) or too permissive (resulting in ignorance). For this reason, we investigate how a context-dependent strategy originally defined for possibility theory can be adapted to DS theory. In particular, we use the notion of largely partially maximal consistent subsets (LPMCSes) to characterise the context for when to use Dempster’s original rule of combination and for when to resort to an alternative. To guide this process, we identify existing measures of similarity and conflict for finding LPMCSes along with quality of information heuristics to ensure that LPMCSes are formed around high-quality information. We then propose an intelligent sensor model for integrating this information into the AgentSpeak framework which is responsible for applying evidence propagation to construct compatible information, for performing context-dependent combination and for deriving beliefs for revising an agent’s belief base. Finally, we present a power grid scenario inspired by a real-world case study to demonstrate our work.

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It is thought that direct personal experience of extreme weather events could result in greater public engagement and policy response to climate change. Based on this premise, we present a set of future climate scenarios for Ireland communicated in the context of recent, observed extremes. Specifically, we examine the changing likelihood of extreme seasonal conditions in the long-term observational record, and explore how frequently such extremes might occur in a changed Irish climate according to the latest model projections. Over the period (1900-2014) records suggest a greater than 50-fold increase in the likelihood of the warmest recorded summer (1995), whilst the likelihood of the wettest winter (1994/95) and driest summer (1995) has respectively doubled since 1850. The most severe end-of-century climate model projections suggest that summers as cool as 1995 may only occur once every ∼7 years, whilst winters as wet as 1994/95 and summers as dry as 1995 may increase by factors of ∼8 and ∼10 respectively. Contrary to previous research, we find no evidence for increased wintertime storminess as the Irish climate warms, but caution that this conclusion may be an artefact of the metric employed. It is hoped that framing future climate scenarios in the context of extremes from living memory will help communicate the scale of the challenge climate change presents, and in so doing bridge the gap between climate scientists and wider society.

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Wearable devices performing advanced bio-signal analysis algorithms are aimed to foster a revolution in healthcare provision of chronic cardiac diseases. In this context, energy efficiency is of paramount importance, as long-term monitoring must be ensured while relying on a tiny power source. Operating at a scaled supply voltage, just above the threshold voltage, effectively helps in saving substantial energy, but it makes circuits, and especially memories, more prone to errors, threatening the correct execution of algorithms. The use of error detection and correction codes may help to protect the entire memory content, however it incurs in large area and energy overheads which may not be compatible with the tight energy budgets of wearable systems. To cope with this challenge, in this paper we propose to limit the overhead of traditional schemes by selectively detecting and correcting errors only in data highly impacting the end-to-end quality of service of ultra-low power wearable electrocardiogram (ECG) devices. This partition adopts the protection of either significant words or significant bits of each data element, according to the application characteristics (statistical properties of the data in the application buffers), and its impact in determining the output. The proposed heterogeneous error protection scheme in real ECG signals allows substantial energy savings (11% in wearable devices) compared to state-of-the-art approaches, like ECC, in which the whole memory is protected against errors. At the same time, it also results in negligible output quality degradation in the evaluated power spectrum analysis application of ECG signals.

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Scheduling jobs with deadlines, each of which defines the latest time that a job must be completed, can be challenging on the cloud due to incurred costs and unpredictable performance. This problem is further complicated when there is not enough information to effectively schedule a job such that its deadline is satisfied, and the cost is minimised. In this paper, we present an approach to schedule jobs, whose performance are unknown before execution, with deadlines on the cloud. By performing a sampling phase to collect the necessary information about those jobs, our approach delivers the scheduling decision within 10% cost and 16% violation rate when compared to the ideal setting, which has complete knowledge about each of the jobs from the beginning. It is noted that our proposed algorithm outperforms existing approaches, which use a fixed amount of resources by reducing the violation cost by at least two times.

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Large construction projects create numerous hazards, making it one of the most dangerous industries in which to work. This element of risk increases in urban areas and can have a negative impact on the external stakeholders associated with the project, along with their surrounding environments. The aim of this paper is to identify and document, in an urban context, the numerous issues encountered by on-site project managers from external stakeholders and how they affect a construction project. In addressing this aim, the core objective is to identify what issues are involved in the management of these stakeholders. In order to meet this requirement, a qualitative methodology encompassing an informative literature review followed by five individual case study interviews. The data gathered is assessed qualitatively using mind mapping software. A number of issues are identified which have an impact on the external stakeholders involved, and also how they affected proceedings on site. Collectively the most commonly occurring issues are environmental, legal, health and safety and communication issues. These ranged from road closures and traffic disruption to noise, dust and vibrations from site works. It is anticipated that the results of this study will assist and aid project managers in identifying issues considering external stakeholders, particularly on urban construction projects. A wide range of issues can develop depending on the complexity and nature of each project, but this research will illustrate and reinforce to project managers, that identifying issues early, effective communication and appropriate liaising can be used to manage the issues considering external stakeholders.

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In May 2006, the NEC contract was introduced as the preferred contract for Northern Ireland public sector works. This was subsequently followed by the 2007 economic crash and ensuing recession, which continues to affect the Northern Ireland Construction Industry, to a greater extent than the remainder of the United Kingdom (UK). However, use of the NEC contract has increased during this period, particularly in the public sector. There has been debate in the literature regarding the impact of the NEC contract on adversarial behaviour, but little consideration of the impact of external economic factors on the use of the NEC contract. Using a sequential mixed method approach, the study aims to fill this gap in knowledge, through examination of the impact the economic downturn has had on the operation of the NEC contract in Northern Ireland. Qualitative and quantitative findings show that the demands placed by the NEC contract, and the effects of the economic recession, have exerted opposing forces contract implementation, thus hindering its execution. The findings can lead to a deeper understanding, in the context of both industry and academia, of situations where a lack of resources may negatively impact the operation of the NEC contract.

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The UK’s Royal Town Planning Institute (RTPI) has celebrated its centenary in 2014, marking 100 years of close relationships between university-based planning schools and a professional body focused on planning practice. During this period, the context for university education and the very idea of planning have changed dramatically contributing to a continual renegotiation of the relationships between the planning profession and the educational institutions it accredits. These changes have been particularly pronounced in the last 10 years where a number of factors have forced a rapid change in the nature of planjavascript:void(0);ning education in the UK. This has included a boom and then slump in the number of planning students linked to the dynamics of national economic situation, a reorganization of many planning school curricula, and their merger with cognate disciplines such as geography and an increased focus on research output, rather than professional engagement as the key indicator of institutional success. This last factor adds a particularly new dimension to the profession-university relationship, which could potentially lead to either straining of tensions or a synergy through research-led teaching that could significantly benefit both. This chapter will briefly review the evolution of UK planning schools and of the main ideas informing planning education. It will then describe the current profile of UK planning schools, based on an extensive national survey conducted on behalf of the Royal Town Planning Institute. The paper will then critically review the main challenges and opportunities facing UK planning schools in the context of changes in both planning practice and higher education. It will then move on to the concept of research-led teaching, drawing on current practice in the UK and review how well this concept serves students and the idea of developing reflective planning practitioners. Finally, the paper will seek to draw broad lessons from the experience of the UK and reflect on the type of planning education that can best serve planning professions in a variety of international contexts in the future.

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This chapter focuses on the growing tendency of international human rights law to require states to protect the rights of non-nationals who are in the state unlawfully and of nationals and non-nationals who are outside the state, especially when any of these people are involved in terrorist or counter-terrorist activity. It reviews these additional obligations within a European context, focusing on EU law and the law of the European Convention on Human Rights and drawing on the case law of UK courts. Part 1 considers when a European state must grant asylum to alleged terrorists on the basis that otherwise they would suffer human rights abuses in the state from which they are fleeing. Part 2 examines whether, outside of asylum claims, a European state must not deport or extradite an alleged terrorist because he or she might suffer an abuse of human rights in the receiving state. Part 3 looks at whether a European state whose security forces are engaged in counter-terrorism activities abroad is obliged to protect the human rights of the individuals serving in those forces and/or the human rights of the alleged terrorists they are confronting. While welcoming the extension of state responsibility, the chapter notes that it is occurring in a way which introduces three aspects of relativity into the protection of human rights. First, European law protects only some human rights extra-territorially. Second, it protects those rights only when there is ‘a real risk’ of their being violated. Third, sometimes it protects those rights only when there is a real risk of their being violated ‘flagrantly’.

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Introduction and Aims. While the role of the family in adolescent substance use has been well documented, few studies have attempted to explore in-depth youth perceptions of how these familial processes/dynamics influence teenage substance use. This paper reports the findings from a study exploring risk and protective factors for teenage substance use within the context of the family as perceived by young people with a view to informing current and future family based prevention and education interventions.
Design and Methods. Data collection took place in nine post-primary schools across Northern Ireland. Nine focus groups using participatory techniques were facilitated with a purposive sample of sixty-two young people (age 13-17 years). Data were transcribed verbatim and analysed using a content/thematic analysis.
Results. Three broad themes/aspects of the family emerged from the data, which may serve to protect or attenuate the risk of substance use among young people. Parent-child attachment was a major theme identified in protecting adolescents from substance use in addition to effective parenting particularly an authoritative style of parenting supplemented by parental monitoring and good parent-child communication to encourage child disclosure. Family substance use was deemed to impact on children’s substance use if exposed at an early age and the harms associated with PSM were discussed in detail.
Discussion and Conclusions. The qualitative approach provides insight into current understanding of youth perceptions of substance use in the context of family dynamics. A number of recommendations are outlined. Family based (preventive) interventions/parenting programmes may benefit from components on effective parenting including authoritative styles, parental monitoring, effective communication, spending time together (building attachments), parent-child conflict, adolescent development and factors which impact on parenting. Parenting programmes tailored to mothers and fathers may be beneficial. School based interventions targeting children/adolescents may be best placed to target children living with parental substance misuse.
Keywords: substance/substance related disorders, focus groups, young people/adolescent,