21 research outputs found

    Formal Verification of Real-Time Function Blocks Using PVS

    Full text link
    A critical step towards certifying safety-critical systems is to check their conformance to hard real-time requirements. A promising way to achieve this is by building the systems from pre-verified components and verifying their correctness in a compositional manner. We previously reported a formal approach to verifying function blocks (FBs) using tabular expressions and the PVS proof assistant. By applying our approach to the IEC 61131-3 standard of Programmable Logic Controllers (PLCs), we constructed a repository of precise specification and reusable (proven) theorems of feasibility and correctness for FBs. However, we previously did not apply our approach to verify FBs against timing requirements, since IEC 61131-3 does not define composite FBs built from timers. In this paper, based on our experience in the nuclear domain, we conduct two realistic case studies, consisting of the software requirements and the proposed FB implementations for two subsystems of an industrial control system. The implementations are built from IEC 61131-3 FBs, including the on-delay timer. We find issues during the verification process and suggest solutions.Comment: In Proceedings ESSS 2015, arXiv:1506.0325

    Interactive versus Passive Distraction and Parent Psychoeducation as pain management techniques during pediatric venepuncture: A Randomized Controlled Trial

    Get PDF
    Objectives The aim of this research was twofold: to explore 1) the efficacy of active vs. passive distraction on self-reported pain and distress of children during a venepuncture; and 2) the impact ofparental psychoeducation on child and parent outcomes, parental knowledge of distraction procedures and parental engagement in effective pain management strategies.  Methods This cross-sectional study included 213 children scheduled for a venepuncture, and one of their parents, who were randomly allocated to one of four conditions; interactive distraction, passive distraction, interactive distraction with parent psychoeducation and passive distraction with parent psychoeducation. ANCOVA’s were used to investigate the impact of distraction type and the use of parent psychoeducation on child and parent pain related outcome variables.  Results Statistical analyses revealed no significant differences between groups for child-reported pain and distress. Parents who received parent psychoeducation had a significantly higher level of knowledge than parents who did not receive psychoeducation, but did not engage in more effective pain management behaviour.  Conclusions The results indicated that passive vs. active distraction does not have a significantly different influence on child pain-related outcome variables. In addition, while psychoeducation was demonstrated to be effective in increasing parental knowledge, it was not sufficient to change parental behaviour

    Reference state and benchmark concepts for better biodiversity conservation in contemporary ecosystems

    Get PDF
    Measuring the status and trends of biodiversity is critical for making informed decisions about the conservation, management or restoration of species, habitats and ecosystems. Defining the reference state against which status and change are measured is essential. Typically, reference states describe historical conditions, yet historical conditions are challenging to quantify, may be difficult to falsify, and may no longer be an attainable target in a contemporary ecosystem. We have constructed a conceptual framework to help inform thinking and discussion around the philosophical underpinnings of reference states and guide their application. We characterize currently recognized historical reference states and describe them as PreHuman, Indigenous Cultural, Pre-Intensification and Hybrid-Historical. We extend the conceptual framework to include contemporary reference states as an alternative theoretical perspective. The contemporary reference state framework is a major conceptual shift that focuses on current ecological patterns and identifies areas with higher biodiversity values relative to other locations within the same ecosystem, regardless of the disturbance history. We acknowledge that past processes play an essential role in driving contemporary patterns of diversity. The specific context for which we design the contemporary conceptual frame is underpinned by an overarching goal - to maximize biodiversity conservation and restoration outcomes in existing ecosystems. The contemporary reference state framework can account for the inherent differences in the diversity of biodiversity values (e.g. native species richness, habitat complexity) across spatial scales, communities and ecosystems. In contrast to historical reference states, contemporary references states are measurable and falsifiable. This 'road map of reference states' offers perspective needed to define and assess the status and trends in biodiversity and habitats. We demonstrate the contemporary reference state concept with an example from south-eastern Australia. Our framework provides a tractable way for policy-makers and practitioners to navigate biodiversity assessments to maximize conservation and restoration outcomes in contemporary ecosystems

    Whitefield News

    Get PDF
    File includes: January 2017 Volume 4, Issue 7 February 2017 Volume 4, Issue 8 March 2017 Volume 4, Issue 9 April 2017 Volume 4, Issue 10 May 2017 Volume 4, Issue 11 June 2017 Volume 4, Issue 12 July 2017 Volume 5, Issue 1 August 2017 Volume 5, Issue 2 September 2017 Volume 5, Issue 3 October 2017 Volume 5, Issue 4 November 2017 Volume 5, Issue 5 December 2017 Volume 5, Issue

    Data Resource Profile: The World Health Organization Study on global AGEing and adult health (SAGE)

    Get PDF
    Population ageing is rapidly becoming a global issue and will have a major impact on health policies and programmes. The World Health Organization's Study on global AGEing and adult health (SAGE) aims to address the gap in reliable data and scientific knowledge on ageing and health in low- and middle-income countries. SAGE is a longitudinal study with nationally representative samples of persons aged 50+ years in China, Ghana, India, Mexico, Russia and South Africa, with a smaller sample of adults aged 18-49 years in each country for comparisons. Instruments are compatible with other large high-income country longitudinal ageing studies. Wave 1 was conducted during 2007-2010 and included a total of 34 124 respondents aged 50+ and 8340 aged 18-49. In four countries, a subsample consisting of 8160 respondents participated in Wave 1 and the 2002/04 World Health Survey (referred to as SAGE Wave 0). Wave 2 data collection will start in 2012/13, following up all Wave 1 respondents. Wave 3 is planned for 2014/15. SAGE is committed to the public release of study instruments, protocols and meta- and micro-data: access is provided upon completion of a Users Agreement available through WHO's SAGE website (www.who.int/healthinfo/systems/sage) and WHO's archive using the National Data Archive application (http://apps.who.int/healthinfo/systems/surveydata

    Scientific overview on CSCI-CITAC Annual General Meeting and 2017 Young Investigators’ Forum

    No full text
    The 2017 Annual General Meeting of the Canadian Society of Clinician Investigators (CSCI) and Clinician Investigator Trainee Association of Canada/Association des Cliniciens-Chercheurs en Formation du Canada (CITAC/ACCFC) was a national Annual General Meeting (AGM) held in Toronto, Ontario November 20–22, 2017, in conjunction with the University of Toronto Clinician Investigator Program Research Day. The theme for this year’s meeting was “Roll up your sleeves—How to manage your physician scientist career”, emphasizing lectures and workshops that were designed to provide tools for being proactive and successful in career planning. The keynote speakers were Dr. Rod McInnes (McGill University and Canadian Institutes of Health Research Acting President), who was the Distinguished Scientist Award recipient, Dr. David Goltzman (McGill University), who was the 2017 Henry Friesen Award recipient, Dr. Gillian Hawker (University of Toronto), Dr. Mike Sapieha (Université de Montréal), who was the 2017 Joe Doupe Award recipient, and Dr. Alex MacKenzie (Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa). The workshops, focusing on career development for clinician scientists, were hosted by Dr. Lisa Robinson, Dr. Nicola Jones, Kevin Vuong, Fran Brunelle, Dr. Jason Berman and Dr. Alan Underhill. Further to this, the Young Investigators’ Forum encompasses presentations from scientist-clinician trainees from across the country. All scientific abstracts are summarized in this review. There were over 100 abstracts showcased at this year’s meeting during the highlighted poster sessions, with six outstanding abstracts selected for oral presentations during the President’s Forum

    Russia’s forests in a global economy: how consumption drives environmental change

    No full text
    corecore