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991.
The UK public sector has been exposed to competition as a means of enhancing its performance. HE institutions now compete for resources on the basis of research. In this competitive environment the crucial question is not why one HE institution is more successful than another at research but why some institutions are home to a large number of departments that are successful. The answer lies in exploring what gives competitive advantage at the level of the department, discipline and nation. Porter' three layer ‘diamond’ model of competitive advantage is proposed as a framework for this exploration. This identified four major components: factor conditions (research orientation and accumulated wealth of institution); demand conditions (demand by academy for departmental research as measured by ability to secure external income/research students); related and supporting departments (research strength of institution and presence of a relevant cluster of research‐strong departments) and departmental strategy, structure and rivalry (ability to focus departmental attention on the successful training of research students and publication in refereed journals). In a linked paper this model provided a framework to evaluate research performance in the discipline of geography (Curran, 2001).  相似文献   
992.
The aim of this study was to compare the somersaulting techniques used in the 16 highest-scoring and 16 lowest-scoring Roche vaults. Our hypothesis was that the gymnasts performing the highest-scoring Roche vaults would demonstrate a better technique than those performing the lowest-scoring Roche vaults while on the horse (pushing off the horse more effectively), somersaulting (executing most of the required somersaults higher in flight), and landing (showing a greater control). A 16-mm motion picture camera, operating at 100 Hz, recorded the vaults during the official competition. The two-dimensional direct linear transformation was used for spatial reconstruction. The results of t-tests (P < 0.05) indicated that, compared with the low-scoring gymnasts, the high-scoring gymnasts had: (1) greater height of body centre of mass and a more fully extended body position at the horse take-off; (2) greater height of body centre of mass at the peak of post-flight, knee release, and touchdown on the mat; (3) greater horizontal and vertical displacements of body centre of mass, greater somersaulting rotation, and longer time from the knee release to mat touchdown; and (d) markedly smaller landing point deductions. In conclusion, a successful Roche vault is likely when the focus is on: (a) leaving the horse with a large vertical velocity in an extended body position to achieve a high trajectory of centre of mass by first extending the legs, then immediately pushing off the horse vigorously, using the muscles of the upper extremity; (b) grasping the knees immediately after the take-off from the horse, achieving the tightly tucked body position early during the ascent to the peak, and completing two-thirds of the required somersaults at a great height; (c) releasing the knees and extending the body above the top level of the horse; and (d) contacting the mat with a high body centre of mass position.  相似文献   
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