The design and testing of a wire velocimeter

The basic principles underlying the design of a velocimeter based on an unwinding wire, for use in athletics research, are discussed. It is shown by theoretical analysis that, in order to avoid runaway effects, the tension on the wire should be either high or low but not of intermediate strength. The low tension regime is shown to be theoretically the most favourable as it combines high accuracy of speed measurements in decelerated motion with insensitivity to resonance oscillations of the wire. Practical considerations concerning the ruggedness of the apparatus, however, favour the high tension regime. A modern apparatus incorporating microprocessors and working with thin nylon wire stretched by a force of the order of 1 N, i.e. in the high tension regime, has been constructed and tested. The test results show that the velocity of decelerated motions (up to decelerations of the order of 10 m s-2) can be faithfully recorded in the velocity range 0-15 m s-1. The relative error for the measurement of constant speed up to 15 m s-1 is about one in a thousand, which is very small and practically unattainable by other methods. An application to the study of the long jump is demonstrated and validated by the use of film analysis.     

Problematical aspects of expatriate educational research with and in developing countries

Discussions of the problems of expatriate educational research with and in developing countries are at the core of this paper. How should a research project be set up? Who should initiate it and finance it? How does it fit into an overall development strategy? These and other questions are analysed sensitively and with understanding. The paper also examines how research questions should be formulated and how the research should be designed. Inevitably there are hidden objectives which do not appear explicit in the early stages. There are yet others which should be made explicit. Problems also arise over collecting and disseminating data, especially when the time comes to publish a report. So often political and other considerations influence the final report. Ultimately, however, the success or failure and the value or otherwise of any research depends on an intricate web of relationships, at the heart of which must be mutual trust.     

The underarm throw for accuracy in children

Forty boys and girls of two age groups (mean ages 52 and 70 months, respectively) performed 35 trials on a throwing task demanding accuracy. As might be expected, the older children were significantly more accurate than the younger ones but there were no sex differences. Film analysis of the throws showed that, although both age groups attempted to employ the adult strategy of varying velocity while keeping ball-release angle constant, the younger group was less successful in the latter aspect. The manner in which consistent release angles were arrived at by the older group was through the use of a movement pattern in which the elbow angle did not change during the forward swing. Such a movement pattern appeared less frequently in the younger age group. The results of this study provide support for a mode of research identifying functionally relevant kinematic variables that can subsequently be shown to follow from distinctive execution categories. In such a way, changes in outcome measures with increasing age and/or skill level can be functionally understood and identified.     

Integrating data-based decision making,Assessment for Learning and diagnostic testing in formative assessment

Recent research has highlighted the lack of a uniform definition of formative assessment, although its effectiveness is widely acknowledged. This paper addresses the theoretical differences and similarities amongst three approaches to formative assessment that are currently most frequently discussed in educational research literature: data-based decision making (DBDM), Assessment for Learning (AfL) and diagnostic testing (DT). Furthermore, the differences and similarities in the implementation of each approach were explored. This analysis shows that although differences exist amongst the theoretical underpinnings of DBDM, AfL and DT, the combination of these approaches can create more informed learning environments. The thoughtful integration of the three assessment approaches should lead to more valid formative decisions, if a range of evidence about student learning is used to continuously optimise student learning.     

Improving the Entrepreneurial Competencies of Dutch Dairy Farmers through the Use of Study Groups

Abstract

The objective of this paper is to describe and analyse the role that study groups might play in improving the entrepreneurial competencies of farmers. The most important competencies are described. Emphasis is placed on group learning processes and participatory approaches. Theories of adult learning and extension paradigms in relation to our experiences in the ‘Innovative Entrepreneurship’ study are addressed. We conclude that in our research, participatory approaches and using study groups are an aid to gaining explicit and implicit knowledge. Consequently, they are effective methods for training entrepreneurial competencies and creating an environment in which participants are able to learn effectively.