422 research outputs found

    Magnetic flux density distribution in axial flux machine cores

    Get PDF
    [Abstract]: A three-dimensional analytical model is presented to evaluate the magnetic flux density distribution in the core of an axial flux machine. The model predicts significantly higher flux density near the outer radius of the core than that at the inner radius. This has been confirmed by experimental test results. The model also predicts the presence of a curvature-related radial component in the magnetic flux density distribution. It is argued that if it can be established that eddy currents, induced by the tendency for the flux to flow radially, have sufficient shielding effect, then radial flux can be ignored and two-dimensional modelling can be use

    Visualizing classification of natural video sequences using sparse, hierarchical models of cortex.

    Get PDF
    Recent work on hierarchical models of visual cortex has reported state-of-the-art accuracy on whole-scene labeling using natural still imagery. This raises the question of whether the reported accuracy may be due to the sophisticated, non-biological back-end supervised classifiers typically used (support vector machines) and/or the limited number of images used in these experiments. In particular, is the model classifying features from the object or the background? Previous work (Landecker, Brumby, et al., COSYNE 2010) proposed tracing the spatial support of a classifier’s decision back through a hierarchical cortical model to determine which parts of the image contributed to the classification, compared to the positions of objects in the scene. In this way, we can go beyond standard measures of accuracy to provide tools for visualizing and analyzing high-level object classification. We now describe new work exploring the extension of these ideas to detection of objects in video sequences of natural scenes

    The Sustainable Farm Families Project : changing attittudes to health

    Full text link
    Introduction: Farm health and safety has historically focussed on strategies such as injury prevention, safety audits and fulfilling legislative responsibilities. However, farmer injuries mask deeper health issues including higher rates of cancer, suicides, cardiovascular disease and stress. The relationship between occupational health and safety and farm family health has not been fully investigated. The Sustainable Farm Families (SFF) project attempts to make this connection in order to address premature death, morbidity and injury on Australian farms. The SFF project illustrates how increasing health literacy through education and physical assessment can lead to improved health and knowledge outcomes for farm families.Methods: The SFF project focuses on the human resource in the triple bottom line and is working with farmers, families, industry and universities to collaboratively assess and promote improvement in the health and wellbeing of farm families. Based on a model of extension that engages farm families as active learners where they commit to healthy living and safe working practices, the SFF project is proving to be an effective model for engaging communities in learning and change. Health education and information is delivered to farm men and women aged 18 to 75 years using a workshop format. Pre- and post-knowledge surveys, annual physical assessments and focus group discussions form the methodological context for the research over a three-year intervention.Results: This article discusses the progress of the research outlining the design of the SFF project, the delivery and extension processes used to engage 321 farm families from within a broadacre and dairy-farming family sample. The article presents key learnings on intersectoral collaboration, engaging farmers and families in health, and the future for this project extending into agricultural industries across the nation. Key results reveal that health issues do exist in farming families and are often underreported by family members. Health indicators were at a level where referral and intervention was required in over 60% of men and 70% of women in both broad acre and dairy industries. Farm men and women verbalised health concerns relating to access, support and control mechanisms of the health system. Participants also revealed how they put into practice their new knowledge and how this has influenced their health.Conclusions: The key learning is that farm men and women who are at high risk of premature morbidity and mortality will participate in health education and assessment programs based on industry collaboration with high levels of individual participation. This program provides evidence that farmers will engage with health professionals if programs are presented to them in personally engaging and relevant ways. The SFF program is a definite tool for interventional health promotion that supports attitudinal change to health and farming practices.<br /

    Global effects in quaternionic quantum field theory

    Full text link
    We present some striking global consequences of a model quaternionic quantum field theory which is locally complex. We show how making the quaternionic structure a dynamical quantity naturally leads to the prediction of cosmic strings and non-baryonic hot dark matter candidates.Comment: 11 pages, no figures, revte

    Suicide and accidental death in Australia’s rural farming communities: a review of the literature

    Full text link
    Introduction: Australia's farmers constitute a heterogeneous group within the rural population. This literature review incorporates four broad areas: an understanding of farming communities, families and individuals and the contexts in which they live and work; an exploration of the challenges to morbidity and mortality that these communities face; a description of the patterns of suicide and accidental death in farming communities; and an outline of what is missing from the current body of research. Recommendations will be made on how these gaps may be addressed. Methods: In developing this comprehensive literature review, a snowballing and saturation approach was adopted. Initial search terms included suicid*, farm*, accident*, fatal*, death, sudden death, rural OR remote, Australia and NOT Australia. Databases searched included SCOPUS, PubMed, Proquest and SafetyLit; research from 1995 onwards was examined for relevance. Earlier seminal texts were also included. Reference lists of retrieved articles were searched and citations explored for further relevant research material. The primary focus was on Australian peer-reviewed research with supplementary grey literature. International material was used as examples. Results: The literature variously describes farmers as members of both rural farming communities and farming families, and as individuals within an occupational classification. Within each of these classifications, there is evidence of the cumulative impact of a multiplicity of social, geographical and psychological factors relating to work, living and social arrangements that impact the health and wellbeing of Australia's farmers and their families, particularly accidental death and suicide. Research consistently demonstrates traumatic death to be at a greater rate than in the general Australian population, with reductions found more recently in some modes of farming-related accidental death. Patterns of accidental death and suicide are commonly linked to the changing shape of contemporary farming. Suicide rates are also frequently described in relation to lethality and accessibility of means. The limitations of suicide and accidental death data are considerable. Conclusion: While there is consistent reporting of heightened levels of risk for suicide and accidental death in farming communities the limitations of the research remain significant. There are substantial gaps in current knowledge, and the body of research to date lacks clarity, inclusiveness and contextual specificity. Absent from the literature is any investigation of the impact of these frequently preventable deaths on the families and communities in which they occur. Recommendations for future research are suggested

    The Emergence of Interactive Behaviour: A Model of Rational Menu Search

    Get PDF
    One reason that human interaction with technology is difficult to understand is because the way in which people perform interactive tasks is highly adaptive. One such interactive task is menu search. In the current article we test the hypothesis that menu search is rationally adapted to (1) the ecological structure of interaction, (2) cognitive and perceptual limits, and (3) the goal to maximise the trade-off between speed and accuracy. Unlike in previous models, no assumptions are made about the strategies available to or adopted by users, rather the menu search problem is specified as a reinforcement learning problem and behaviour emerges by finding the optimal policy. The model is tested against existing empirical findings concerning the effect of menu organisation and menu length. The model predicts the effect of these variables on task completion time and eye movements. The discussion considers the pros and cons of the modelling approach relative to other well-known modelling approaches

    "Oops...": Mobile Message Deletion in Conversation Error and Regret Remediation

    Get PDF
    Message deletion in mobile messaging apps allows people to “unsay” things they have said. This paper explores how and why people use (or do not use) this feature within remediation strategies after a communication error is identified. We present findings from a multi-stage survey designed to explore people’s general experiences of the message deletion feature (N = 401), peoples’ experiences of using this feature during the remediation of an error (N = 70), and receivers’ perceptions around recent message deletions (N = 68). While people are typically aware of the deletion feature, it is infrequently used. When used, it is primarily done so to improve conversations by reducing confusion between conversation partners. We found people being aware of message deletions creating information-gaps which can provoke curiosity in recipients, causing them to develop narratives to help address the uncertainty. We found concerns amongst senders that these narratives would be of a negative nature, having an undesirable impact on how others perceive them. We use our findings to suggest ways in which mobile messaging apps could improve conversational experiences around erroneous and regrettable messages

    Making a Task Difficult: Evidence That Device-Oriented Steps Are Effortful and Error-Prone

    Get PDF
    Errors in the execution of procedural tasks can have severe consequences. Attempts to ameliorate these slip errors through increased training and motivation have been shown to be ineffective. Instead, we identified the steps in a task procedure on which errors are most likely to occur, so that these might be designed out of the task procedure in the first place. Specifically, we considered whether device-oriented steps (i.e., steps in the task procedure that do not directly contribute to the achievement of the task goal) are more error-prone than task-oriented steps (i.e., steps that do directly contribute to the task goal). Two experiments are reported in which participants were trained to perform a novel procedural task. Across conditions, we manipulated the extent to which each step in the task procedure appeared to contribute to the achievement of the task goal (i.e., alternating the assignment of a task step between device- and task-oriented), while keeping the interface and underlying task procedure the same. Results show that participants made more errors and took longer to complete a task step when it played a device-oriented role rather than a task-orientated role. These effects were exacerbated by the introduction of a secondary task designed to increase working memory load, suggesting that when a task step plays a device-oriented role it is more weakly represented in memory. We conclude that device-oriented task steps are inherently problematic and should be avoided where possible in the design of task procedures

    The Future of Education in Georgia : A+ Education Reform Act of 2000

    Full text link
    [In 1999] the Governor of the State of Georgia issued a challenge to his newly formed Education Reform Study Commission. He said: I am counting on this group to shake up the educational system as it exists today in Georgia. We have been able to put together a group of people who are both experienced with and devoted to educational issues, and I know that they will be able to develop sound ideas that will help restore public confidence in our schools. And shake up they did. As a result of the Commission\u27s work, House Bill 1187 was introduced to the Georgia General Assembly [in 2000]. A hotly debated bill, the A+ Education Reform Act of 2000 will affect all aspects of the educational system. As a part of this reform the leaders of Georgia\u27s educational institutions will come together to form the Education Coordinating Council. Their purpose will be to improve public education through a seamless coordination among Georgia\u27s public education providers. On March 31, we will have three very important members of this council to discuss their outlook on education in Georgia: Governor Roy Barnes (J.D. \u2772), Chairman of the State School Board Otis Brumby (J.D. \u2765), and Chancellor Stephen Portch
    corecore