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ABSTRACT

This study investigates the spatial relationship of performance variables for soccer free kicks. In order to suggest ways in which players might optimise their performance, we collected data from free kicks (<35 m to goal line) of two German Bundesliga seasons (2013/14, 2014/15) (n = 1624). In the analysis, we applied the ISO-map approach using colour gradients to visualise the mean values of a variable on a 2D-map of the pitch. Additionally, variograms were used to describe the degree of spatial dependence of the free kick variables. Results show that DENSITY, TYPE OF PLAY, PLAYERS IN WALL, DISTANCE TO WALL and RULE VIOLATION were strongly spatially dependent. Centrality and proximity to the goal increased the variables PLAYERS IN WALL, RULE VIOLATIONS and INTERRUPTION TIME, and the ratio of goals scored increased from 5.9% (central far) to 10.9% (central near). In 70.9% of the shots, players preferred a switched laterality, which did not result in a higher success rate. Furthermore, there was no statistical advantage for the defensive team when DISTANCE TO WALL was below 9.15 m or when there was a RULE VIOLATION. Crosses had a success rate (i.e., first controlled ball contact after the cross) of 20.8%. Played with natural laterality, they were 5% more successful than with switched laterality. Crosses from the right side outside the penalty box were 10% more successful than from the left side. Therefore, it might be worthwhile practising the defence of balls coming from this side.  相似文献   
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Zusammenfassung. Traditionelle und deduktive Informationssysteme werden heute immer noch isoliert voneinander modelliert und implementiert. Für die meisten Benutzer sind jedoch Systeme wichtig, die ihren allt?glichen Informationsbedarf decken und darüber hinaus deduktive F?higkeiten besitzen. Der bekannte Entity-Relationship-Ansatz zur konzeptionellen Datenmodellierung wird in dieser Arbeit so erweitert, da? damit solche integrierten Systeme modelliert werden k?nnen. Au?erdem wird eine Klassifizierung ableitbarer Daten eingeführt, die dem Analytiker Hilfestellung bei der Frage gibt, welche ableitbaren Daten bei der Modellierung berücksichtigt werden sollen und welche nicht. Eingegangen am 2. November 1994 / Angenommen am 30. M?rz 1995  相似文献   
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In current science policies, competition and output incentives are emphasized as a means of making university systems efficient and productive. By comparing eight countries, this article analyzes how funding environments of university research vary across countries and whether more competitive funding systems are more efficient in producing scientific publications. The article shows that there are significant differences in the competitiveness of funding systems, but no straightforward connection between financial incentives and the efficiency of university systems exists. Our results provoke questions about whether financial incentives boost publication productivity, and whether policy-makers should place greater emphasis on other factors relevant to high productivity.  相似文献   
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The displacement of the golf ball struck by a driving club is affected by several player characteristics and equipment parameters and their interrelationships. Some modelling and simulation studies have shown a relationship between shaft length and clubhead speed, supported by a few experimental studies. The aim of the present study was to examine the relationship between driver length and ball launch conditions in an indoor test facility using a ball launch monitor. Nine males considered to be skilled golfers participated in the study. Four driving clubs of total length 117, 119, 124, and 132 cm were assembled from commercially available components and were used to strike golf shots while initial ball velocity, backspin rate, and launch angles were measured. Statistical analysis identified a significant difference in initial launch speed due to club length, a significant difference between participants, but no difference between the trials for a given golfer. A positive trend was noted between backspin and launch angle for all four clubs, and significant inverse associations between initial launch speed and backspin rate and launch angle. However, the combined launch conditions associated with increasing length were not considered optimal, with uncontrolled swingweight and moment of inertia effects considered to be limiting factors.  相似文献   
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