Geometric shape errors in forging: developing a metric and an inverse model

The complexity of the forging process ensures that there is inherent variability in the geometric shape of a forged part. While knowledge of shape error, comparing the desired versus the measured shape, is significant in measuring part quality the question of more interest is what can this error suggest about the forging process set-up? The first contribution of this paper is to develop a shape error metric which identifies geometric shape differences that occur from a desired forged part. This metric is based on the point distribution deformable model developed in pattern recognition research. The second contribution of this paper is to propose an inverse model that identifies changes in process set-up parameter values by analysing the proposed shape error metric. The metric and inverse models are developed using two sets of simulated hot-forged parts created using two different die pairs (simple and 'M'-shaped die pairs). A neural network is used to classify the shape data into three arbitrarily chosen levels for each parameter and it is accurate to at least 77 per cent in the worst case for the simple die pair data and has an average accuracy of approximately 80 per cent when classifying the more complex 'M'-shaped die pair data.

Integrating errors into developmental assessment: 'time' for ages 8-13

It is widely agreed that measurement is of paramount importance to students’ overall development in mathematics. This paper describes a developmental ‘map’ of students’ understanding and skills in measurement, focussed on the topic of Time, that integrates correct and incorrect student ideas. The map is based on a Rasch analysis of data from a large-scale UK national survey for standardising assessment for children from 5 to 14 years of age. It is demonstrated how a partial credit strategy enables a developmental map to be constructed to show students’ strengths and weaknesses in a meaningful and useful summative and formative manner. This map provides evidence, of both a summative and a formative nature, which may enable teachers to craft appropriate and successful learning experiences for children.

Realising air leakage in Australian housing

Air tightness of Australian buildings is a great unknown. Despite testing methods being developed and implemented in many advanced European and North American countries, this has not happened in Australia. This paper notes energy efficiency gains that can be achieved through tighter construction, and follows on from the investigation into testing methodology and literature discussed in TEC 23: Air Leakage in Buildings – Review of International Literature and Standards. Several domestic case studies are used to implement two accepted testing methods and aid to build the case for increased awareness of airtight housing in Australia.

Information leakage and informed trading around unscheduled earnings announcements

While there has been much judicial discussion regarding the competency of Australia's continuous disclosure regime with reference to contemporaneous international standards, there has to date been limited empirical analysis of the Australian system's effectiveness in preventing selective disclosure and information leakage. This paper presents an empirical study of information content and trading behaviour around unscheduled earnings announcements - comprising of profit upgrades, profit warnings and neutral trading statements - made by ASX-listed companies during 2004. The contention is that informed trading impacts on the stock returns and trading volumes of listed entities, and hence abnormal returns or trading volumes observed prior to an announcement provide evidence of information leakage. The paper models a range of factors that potentially influence firm disclosure practices and contribute to the level information asymmetry in the market during the pre- announcement period. Previous research has investigated the influence of firm size and information content in contributing to information leakage. This study further considers the variables of firm growth, capital structure and industry group.

The ethics and practical importance of defining, distinguishing and disclosing nursing errors : a discussion paper

Nurses globally are required and expected to report nursing errors. As is clearly demonstrated in the international literature, fulfilling this requirement is not, however, without risks. In this discussion paper, the notion of ‘nursing error’, the practical and moral importance of defining, distinguishing and disclosing nursing errors and how a distinct definition of ‘nursing error’ fits with the new ‘system approach’ to human-error management in health care are critiqued. Drawing on international literature and two key case exemplars from the USA and Australia, arguments are advanced to support the view that although it is ‘right’ for nurses to report nursing errors, it will be very difficult for them to do so unless a non-punitive approach to nursing-error management is adopted.

Analysis of children's merging errors

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