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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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Zusammenfassung In der Produktfamilienentwicklung werden durch zwei Entwicklungsprozesse, Domain und Application Engineering, zun"achst wiederverwendbare Entwicklungsartefakte produziert, um diese anschlie?end zur Konstruktion von kundenspezifischen Applikationen einzusetzen. Die Wiederverwendbarkeit wird durch die explizite Definition der Variabilit"at der geplanten Applikationen einer Produktfamilie erzielt. Diese proaktive Wiederverwendung ist bisher in den konstruktiven Entwicklungsphasen realisiert, jedoch noch nicht im Test. Mit ScenTED (Scen_ario based TE_st Case D_erivation) wird in diesem Beitrag eine wiederverwendungsorientierte Technik zur Testfallerstellung f"ur den Systemtest, dem Test eines ausf"uhrbaren Systems gegen spezifizierte Use-Cases, von Produktfamilien vorgestellt. ScenTED basiert auf zwei Kernideen: der Erhaltung der Variabilit"at in Testf"allen und der Szenario-basierten Verfeinerung der Testf"alle. Durch die Erhaltung der Variabilit"at wird die Wiederverwendbarkeit von Testf"allen gesichert; die Szenario-basierte Verfeinerung erm"oglicht Nachvollziehbarkeit durch die durchg"angige Nutzung von Szenarien. In diesem Beitrag wird die ScenTED-Technik an einem Beispiel erl"autert und Erfahrungen aus dem industriellen Einsatz diskutiert.
Product family engineering consists of two development processes: Domain engineering and application engineering. Reuseable artefacts are created in the domain engineering process. These artefacts are used for the creation of customer specific applications during the application engineering process. Reusability is achieved with the explicit definition of variability that specifies the potential applications of the product family. The proactive reuse has been realized in the construnction phases of the development process, but not within the test phases. We propose ScenTED (Scen_ario based TE_st Case D_erivation) for the creation of reusable test cases for a use case based system testing in product family engineering. ScenTED has two key ideas: The first is the preservation of variability in test cases and the second idea is the scenario-based refinement of test cases. The preservation of variability ensures the reusability of test cases. The scenario-based refinement enables the traceability from requirements to test cases. We present the ScenTED technique in this article with an example and discuss an industrial case study.
CR Subject Classification D2.5  相似文献   
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Abstract This paper examines the effect of participating in a web-based health programme that promotes personal tracking of high school students' own measurements of a number of health-related parameters. Danish cross-sectional survey data were used to examine the effects of the health programme on various health measures. Both quantile regression models and standard ordinary least squares (OLS) models were used to explore the correlations between the students' participation in the health programme and their body mass index (BMI), body fat percentage, aerobic fitness, and well-being. Participation in the health programme increased BMI and aerobic fitness among students with a BMI or an aerobic fitness value ranging from the 25th percentile to the 75th percentile and reduced body fat percentage among students with the highest percentages of body fat. In addition, the health programme led to an increased feeling of wellbeing among students, especially those with high BMI levels and poor aerobic fitness. As the schools participated in the health programme on voluntary basis and at a financial cost to themselves, the positive effects of participation found can only be stated to be valid among students from committed schools.  相似文献   
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Explicating and measuring opinion leadership continues to bean important theoretical topic, as personal influence and interpersonaldiscussion are widely recognized as shaping public opinion andpolitical behavior. However, the concept of opinion leadershiparose out of empirical research conducted primarily within theUSA. Whether it may be applied to other national contexts remainsto be fully explicated. Furthermore, media information-seekingbehaviors of opinion leaders, such as newspaper use or televisionexposure, seem to be culturally contingent based upon the scantcross-national research to date. This paper examines the ecologicaland constructive validity of the engagement model of the opinionleadership developed within the USA. Employing the EuropeanSocial Survey, I apply this model to fifteen European nationsto assess its validity and explore how media information-seekingbehaviors of opinion leaders may vary across national contexts.The findings suggest that the model may be most valid in WesternEuropean nations. Furthermore, the media use and behaviors ofopinion leaders vary greatly across nations in Europe, thoughlevels of interpersonal political discussion and specific individualsocio-psychological traits do not.  相似文献   
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This article examines the impact of professional education on students' dedication to and identification with a profession. The premise is that professional education is not only about knowledge acquisition and reasoning but also about attitudes and aspirations. In fostering dedication and identification, students' experiences of relevance seem to be important. The concept of coherence seen as an expression of relevance is introduced and measured by four kinds of interactions: Theory–practice interaction, teacher–student interaction, peer interaction and supervisor–student interaction. Analysis indicates that coherence, particularly as theory–practice interaction, peer interaction and supervisor–student interaction, has a significant impact on dedication to and identification with a profession. Longitudinal survey data – collected from students in colleges for teaching, nursing and social work – are analysed.  相似文献   
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Abstract

Purpose: The objective of this article is to analyze the introduction of participatory extension approaches (PEA) in the predominantly supply-driven, hierarchical Vietnamese extension system. Drawing on the case of the so-called Farmer Livestock School (FLS) concept, the authors investigate the potential and challenges of scaling up and out the FLS/PEA principles of participatory training methods, encompassing intensive and interactive training sessions, group-based sharing of experience, practical learning, and learning-by-doing processes.

Design/Methodology/Approach: The article is based on data collected and synthesized from 36 pilot communes from 2000 to 2007 and draws on the extensive insider experience of two of its authors during their work for a DANIDA-funded livestock project.

Findings: At the micro-scale and with external support, FLS has been a successful experiment of using participatory extension approaches in farmer training and extension in the livestock sector. Yet, possibilities of scaling up and institutionalizing FLS remain a challenge given the capacity and resource limitations and the resistance at various levels within the Vietnamese extension system.

Practical Implications: The starting point for successfully institutionalizing participatory extension approaches should be to assess the existing system's root problems and capacities and then gradually and systematically introduce institutional innovations rather than aiming at a complete overhaul of a system that may result in the creation of a parallel universe.

Originality/Value: The FLS project provided a unique opportunity to study the enabling and constraining factors of institutionalizing participatory extension approaches in a traditionally top-down oriented extension system beyond the immediate duration of an externally orchestrated project.  相似文献   
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