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11.
The 16 highest-scored Roche vaults (G1) performed during the 2000 Olympic Games were compared with those receiving the 16 lowest-scores (G2). A 16-mm motion picture camera operating at 100 Hz recorded the vaults during the competition. The results of t tests (p < .05) indicated G1, compared to G2, had (a) shorter time of board support, greater normalised average upward vertical force and backward horizontal force exerted by the board, greater change in the vertical velocity while on the board, and greater vertical velocity at board take-off, (b) comparable linear and angular motions in pre-flight, (c) smaller backward horizontal impulse exerted by the horse, smaller loss of the horizontal velocity while on the horse, and greater horizontal and vertical velocities at horse take-off, (d) greater height and larger horizontal distance of post-flight, (e) higher body mass centre at knee release, and (f) higher mass centre, greater normalised moment of inertia, and smaller vertical velocity at mat touchdown. Therefore, gymnasts and coaches should focus on sprinting the approach; blocking and pushing-off the take-off board rapidly and vigorously; departing the board with a large vertical velocity; exerting large downward vertical force and small forward horizontal force from the hand-stand position while on the horse; departing the horse with large horizontal and vertical velocities; and completing the majority of the double salto forward near the peak of trajectory and releasing the knees above the top of the horse to prepare for a controlled landing.  相似文献   
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The experiences of medical students, residents, and faculty with a computerized literature searching system were evaluated. Third-year medical students, internal medicine and family practice residents, and full-time and voluntary faculty at one medical school had the opportunity to use a full-text and bibliographic medical literature retrieval system free of charge for an eleven-month period. Subjects conducted nearly nine thousand literature searches over a period of 942 system hours. Questionnaire data showed that participants could learn to use and would use an electronic information system, felt capable of using the system, utilized the system for a variety of purposes and in a number of different ways, and viewed the system as a valuable tool in searching the medical literature. The results are discussed in the context of the educational needs of the four user-groups and medical education planning by institutions.  相似文献   
13.
If T maps a convex domain DT into itself, and if {ωn} is a real sequence with range in (0, 1] then the recursive averaging process,
Xn+1=(1?omega;n) XnnnTxn, x0=ξ?DT
generates a sequence {x?n}; with range in DT. Under suitable conditions on DT, T and {ωn} the sequence {x?n} will converge in some sense to a fixed point of T. We prove that if DT is a closed convex subset of a complex Hilbert space H, if Tω = (1 ? ω) I + ωT is a strict contraction for some ω ? (0, 1], and if {ωn} satisfies the conditions,
ωn → 0
and
n=0ωn=∞
then, for arbitrary ξ ? DT, {x?n} converges strongly to (the unique) fixed point of T. We also prove that if DT and {ωn} satisfy the foregoing conditions, if T has at least one fixed point, and if Tω is non-expansive for some ω ? (0, 1], then for all ξ ? DT, {x?n} converges at least weakly to some fixed point of T. Finally, we apply these results to linear equations involving bounded normal operators and obtain an extension of the classical Neumann operator series.  相似文献   
14.
There is much disagreement in the literature over the extent to which graduates are mismatched in the labour market and the reasons for this. In this paper we utilise the Flexible Professional in the Knowledge Society (REFLEX) data set to cast light on these issues, based on data for UK graduates. We find substantial pay penalties for overeducation for both sexes and for overskilling in the case of men only. When both education and skill mismatch variables are included together in the model only overskilling reduces job satisfaction consistently for both sexes. Using job attributes data it appears that the lower wages of the overqualified may in part simply represent a compensating wage differential for positive job attributes, while for men at least there are real costs to being overskilled.  相似文献   
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A team of performance consultants looks closely at the operations of a cable services provider to identify existing performance gaps, barriers to performance, declining customer satisfaction ratings, and increased call volumes. The team used performance‐centered design (PCD) solutions in order to overcome technical support challenges through increased first‐call resolution. This article summarizes the root cause analysis, process, and the application of PCD solutions to close performance gaps, along with lessons learned from this case study.  相似文献   
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90.4% of the 1977 entrants to concurrent general Teacher Education courses in Ireland North and South responded to a demographic questionnaire. The results are analysed and the two regions contrasted with respect to personal, professional and geographical variables. These indicate that some interesting differences exist but that there are many overall similarities.  相似文献   
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