460 research outputs found

    Testing, Verification and Improvements of Timeliness in ROS Processes

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    This paper addresses the problem improving response times of robots implemented in the Robotic Operating System (ROS) using formal verification of computational-time feasibility. In order to verify the real time behaviour of a robot under uncertain signal processing times, methods of formal verification of timeliness properties are proposed for data flows in a ROS-based control system using Probabilistic Timed Programs (PTPs). To calculate the probability of success under certain time limits, and to demonstrate the strength of our approach, a case study is implemented for a robotic agent in terms of operational times verification using the PRISM model checker, which points to possible enhancements to the operation of the robotic agent

    Agent-based autonomous systems and abstraction engines: Theory meets practice

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    We report on experiences in the development of hybrid autonomous systems where high-level decisions are made by a rational agent. This rational agent interacts with other sub-systems via an abstraction engine. We describe three systems we have developed using the EASS BDI agent programming language and framework which supports this architecture. As a result of these experiences we recommend changes to the theoretical operational semantics that underpins the EASS framework and present a fourth implementation using the new semantics

    ‘Trying to pin down jelly’ - exploring intuitive processes in quality assessment for meta-ethnography

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    Background: Studies that systematically search for and synthesise qualitative research are becoming more evident in health care, and they can make an important contribution to patient care. However, there is still no agreement as to whether, or how we should appraise studies for inclusion. We aimed to explore the intuitive processes that determined the ‘quality’ of qualitative research for inclusion in qualitative research syntheses. We were particularly interested to explore the way that knowledge was constructed. Methods: We used qualitative methods to explore the process of quality appraisal within a team of seven qualitative researchers funded to undertake a meta-ethnography of chronic non-malignant musculoskeletal pain. Team discussions took place monthly between October 2010 and June 2012 and were recorded and transcribed. Data was coded and organised using constant comparative method. The development of our conceptual analysis was both iterative and collaborative. The strength of this team approach to quality came from open and honest discussion, where team members felt free to agree, disagree, or change their position within the safety of the group. Results: We suggest two core facets of quality for inclusion in meta-ethnography - (1) Conceptual clarity; how clearly has the author articulated a concept that facilitates theoretical insight. (2) Interpretive rigour; fundamentally, can the interpretation ‘be trusted?’ Our findings showed that three important categories help the reader to judge interpretive rigour: (ii) What is the context of the interpretation? (ii) How inductive is the interpretation? (iii) Has the researcher challenged their interpretation? Conclusions: We highlight that methods alone do not determine the quality of research for inclusion into a meta-ethnography. The strength of a concept and its capacity to facilitate theoretical insight is integral to meta-ethnography, and arguably to the quality of research. However, we suggest that to be judged ‘good enough’ there also needs to be some assurance that qualitative findings are more than simply anecdotal. Although our conceptual model was developed specifically for meta-ethnography, it may be transferable to other research methodologies

    Practical Verification of Decision-Making in Agent-Based Autonomous Systems

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    We present a verification methodology for analysing the decision-making component in agent-based hybrid systems. Traditionally hybrid automata have been used to both implement and verify such systems, but hybrid automata based modelling, programming and verification techniques scale poorly as the complexity of discrete decision-making increases making them unattractive in situations where complex log- ical reasoning is required. In the programming of complex systems it has, therefore, become common to separate out logical decision-making into a separate, discrete, component. However, verification techniques have failed to keep pace with this devel- opment. We are exploring agent-based logical components and have developed a model checking technique for such components which can then be composed with a sepa- rate analysis of the continuous part of the hybrid system. Among other things this allows program model checkers to be used to verify the actual implementation of the decision-making in hybrid autonomous systems

    Exploration of the beliefs and experiences of Aboriginal people with cancer in Western Australia: a methodology to acknowledge cultural difference and build understanding

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    <p>Abstract</p> <p>Background</p> <p>Aboriginal Australians experience poorer outcomes, and are 2.5 times more likely to die from cancer than non-Aboriginal people, even after adjustment for stage of diagnosis, cancer treatment and comorbidities. They are also less likely to present early as a result of symptoms and to access treatment. Psycho-social factors affect Aboriginal people's willingness and ability to participate in cancer-related screening and treatment services, but little exploration of this has occurred within Australia to date. The current research adopted a phenomenological qualitative approach to understand and explore the lived experiences of Aboriginal Australians with cancer and their beliefs and understanding around this disease in Western Australia (WA). This paper details considerations in the design and process of conducting the research.</p> <p>Methods/Design</p> <p>The National Health and Medical Research Council (NHMRC) guidelines for ethical conduct of Aboriginal research were followed. Researchers acknowledged the past negative experiences of Aboriginal people with research and were keen to build trust and relationships prior to conducting research with them. Thirty in-depth interviews with Aboriginal people affected by cancer and twenty with health service providers were carried out in urban, rural and remote areas of WA. Interviews were audio-recorded, transcribed verbatim and coded independently by two researchers. NVivo7 software was used to assist data management and analysis. Participants' narratives were divided into broad categories to allow identification of key themes and discussed by the research team.</p> <p>Discussion and conclusion</p> <p>Key issues specific to Aboriginal research include the need for the research process to be relationship-based, respectful, culturally appropriate and inclusive of Aboriginal people. Researchers are accountable to both participants and the wider community for reporting their findings and for research translation so that the research outcomes benefit the Aboriginal community. There are a number of factors that influence whether the desired level of engagement can be achieved in practice. These include the level of resourcing for the project and the researchers' efforts to ensure dissemination and research translation; and the capacity of the Aboriginal community to engage with research given other demands upon their time.</p

    Suicidality and depression among adult patients admitted in general medical facilities in Kenya

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    <p>Abstract</p> <p>Aim</p> <p>To document Beck Depression Inventory (BDI) II suicidal symptoms among patients admitted to Kenyan non-psychiatric general medical facilities</p> <p>Methods</p> <p>All consenting adults admitted within a period of 4 weeks at 10 general medical facilities in Kenya were interviewed for suicidal symptoms and depression using the BDI-II.</p> <p>Results</p> <p>In all, 2,780 patients responded to item 9 (suicidal symptoms of the BDI-II). The prevalence of all BDI-II suicidal symptoms combined was 10.5%. Thoughts of 'killing oneself but have not carried them out' accounted for 9% of the suicidal symptoms. The younger age group had the highest prevalence of suicidal symptoms and the oldest age group had the least prevalence of suicidal symptoms. The more depressed the patients were on the overall BDI-II score, the higher the prevalence of suicidal symptoms.</p> <p>Conclusion</p> <p>On average 1 out of 10 of the patients had suicidal symptoms, more so in younger than the older people and in the more depressed. These symptoms had not been clinically recognised and therefore not managed. This calls for clinical practice that routinely enquires for suicidal symptoms in general medical wards.</p

    Expert Premier League soccer managers’ use of transformational leadership behaviours and attitude towards sport integrity: An intrinsic case study

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    The present study is the first to examine transformational leadership behaviours and integrity attitudes of expert, Premier League and International level football managers. To provide a rich, detailed exploration of the expert managers’ experiences, a qualitative approach was adopted utilising holistic content analysis. Constructed narratives revealed that the key behaviours demonstrated were inspirational messages or team talks (i.e. inspirational motivation), empathy (i.e. individualised consideration), introducing new training methods (i.e. intellectual stimulation), using exemplar players (i.e. appropriate role modelling), and goal setting (i.e. high performance expectations). However, the use and effect of such behaviours varied greatly between managers. Each of the managers also claimed to have been willing to “bend the rules” as a player and frequently used euphemistic labels to describe such behaviour. However, upon entering management, all three managers claimed to have adjusted such attitudes without providing an explanation for this

    Boundary work: An interpretive ethnographic perspective on negotiating and leveraging cross-cultural identity

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    The complexity of global organizations highlights the importance of members’ ability to span diverse boundaries that may be defined by organization structures, national borders, and/or a variety of cultures associated with organization, nation-based societal and work cultures, industries, and/or professions. Based on ethnographic research in a Japan–US binational firm, the paper describes and analyzes the boundary role performance of the firm\u27s Japanese members. It contributes toward theory on boundary spanning by introducing a “cultural identity negotiation” conceptual framework. We show boundary spanning as a process shaped through the interplay of the contextual issues that make a boundary problematic; an individual\u27s multiple repertoires of cultural knowledge; and the individual boundary spanner\u27s “negotiation”, through interaction with others, of his/her cultural identities – the sense of “who I am” as a cultural being that is fundamental to an individual\u27s self-concept. At the same time, we make transparent the epistemological and methodological foundations of an interpretive ethnographic approach, demonstrating its value for understanding complex organizational processes. Research findings have practical implications for the selection and training of an organization\u27s employees, particularly of persons who may be considered “bicultural”

    Limits on WWZ and WW\gamma couplings from p\bar{p}\to e\nu jj X events at \sqrt{s} = 1.8 TeV

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    We present limits on anomalous WWZ and WW-gamma couplings from a search for WW and WZ production in p-bar p collisions at sqrt(s)=1.8 TeV. We use p-bar p -> e-nu jjX events recorded with the D0 detector at the Fermilab Tevatron Collider during the 1992-1995 run. The data sample corresponds to an integrated luminosity of 96.0+-5.1 pb^(-1). Assuming identical WWZ and WW-gamma coupling parameters, the 95% CL limits on the CP-conserving couplings are -0.33<lambda<0.36 (Delta-kappa=0) and -0.43<Delta-kappa<0.59 (lambda=0), for a form factor scale Lambda = 2.0 TeV. Limits based on other assumptions are also presented.Comment: 11 pages, 2 figures, 2 table
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