Maximum stresses from moving single loads in the members or three-hinged arches     

Emrick A. Werner 《Journal of The Franklin Institute》1892,134(6):426-448

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Perspektiven der Weiterentwicklung des Universitätsgesetzes 2002     

Werner Hauser 《Zeitschrift für Hochschulrecht, Hochschulmanagement und Hochschulpolitik: zfhr》2008,7(2):35-36

Ohne Zusammenfassung  相似文献   

Modellierung von deterministischer Software in Simulink     

Gerald Stieglbauer und Andreas Werner 《Informatik - Forschung und Entwicklung》2005,19(4):189-193

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On the constitution and configuration of higher-order compounds     

Alfred Werner  Marshall McLuhan 《Resonance》1999,4(9):90-94

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Errors in judging "offside" in association football: test of the optical error versus the perceptual flash-lag hypothesis     

Helsen W  Gilis B  Weston M 《Journal of sports sciences》2006,24(5):521-528

The objective of this study was to analyse the correctness of the offside judgements of the assistant referees during the final round of the FIFA 2002 World Cup. We also contrasted two hypotheses to explain the errors in judging offside. The optical error hypothesis is based on an incorrect viewing angle, while the flash-lag hypothesis refers to perceptual errors associated with the flash-lag effect (i.e. a moving object is perceived as spatially leading its real position at a discrete instant signalled by a briefly flashed stimulus). Across all 64 matches, 337 offsides were analysed using digital video technology. The error percentage was 26.2%. During the first 15 min match period, there were significantly more errors (38.5%) than during any other 15 min interval. As predicted by the flash-lag effect, we observed many more flag errors (86.6%) than non-flag errors (13.4%). Unlike the predictions of the optical error hypothesis, there was no significant difference between the correct and incorrect decisions in terms of the positioning of the assistant referees relative to the offside line (0.81 and 0.77 m ahead, respectively). To reduce the typical errors in judging offside, alternative ways need to be considered to teach assistant referees to better deal with flash-lag effects.  相似文献   

Activity profile of top-class association football referees in relation to fitness-test performance and match standard   总被引：1，自引：1，他引：0  

Mallo J  Navarro E  Aranda JM  Helsen WF 《Journal of sports sciences》2009,27(1):9-17

The aim of this study was to examine the kinematic activity profiles, cardiovascular responses and physical fitness of top-class football referees (n=11) during the FIFA Confederations Cup 2005. Computerised match-analyses (n=9) were performed with a two-dimensional photogrammetric video system, and the cardiovascular demand imposed on the referees (n=12) was measured using heart rate recordings. Total distance covered was 10,218, s=643 m of which 3531, s=510 m was covered at high intensities (>3.6 m.s(-1)). Both total distance covered (r2=0.59; P=0.02) and high-intensity activities (r2=0.44; P=0.05) were related to the distance covered by the ball in the same match. The referees ran at high speed 37% further (P=0.01) in the actual tournament than during under-17 top-level officiating. After the 5-min interval during which high-speed running peaked, in the following 5 min the performance was reduced by 19% (P=0.01) in relation to the mean of the game. Mean heart rate was 161, s=9 b.min(-1) (86, s=3% of maximal heart rate (HRmax)). Mean heart rate (expressed as percentage of HRmax) was related in part (r2=0.36; P<0.01) to the number of high-intensity activities performed in the same 5-min interval. The results of this study show that: (1) kinematic activity profiles of top-class referees can be influenced by the distance covered by the ball; (2) the amount of high-speed running (>5 m.s(-1)) best describes the physical performance of referees; (3) heart rate recording can be a useful tool to determine the most intense periods of a match and (4) the new fitness tests adopted by FIFA were poor predictors of match activities.  相似文献   

Muskuläre Regulation bei ermüdungsinduzierter Vorbelastung im Krafttraining     

Prof. Dr. Hans-Alexander Thorhauer  Sven Michel  Norman Stutzig  Lutz Hoffmann  Falk Werner 《Sportwissenschaft》2010,40(3):182-190

International sport strives for increasing the level of performance in sports. Risks of manipulating the performance are not unusual. At the same time, improvements in science, engineering and data processing offer further opportunities for planning effective, low-risk and year-round training programmes for specific sports. This paper presents new approaches based on the example of techniques for strength training. Selected experimental results highlight the limitations and provide conclusions for the scientific foundation and individualization of high performance training. The approach of “muscle pre-fatigue” is verified in a training study with high jumpers. The statements show how important scientifically controlled analysis is for individual training programmes and what high significance they have for optimizing the training process. These will be essential requirements for a legal improvement of high performance in international sport.  相似文献   

Training of perceptual-cognitive skills in offside decision making   总被引：1，自引：0，他引：1  

Catteeuw P  Gilis B  Jaspers A  Wagemans J  Helsen W 《运动与训练心理学杂志》2010,32(6):845-861

This study investigates the effect of two off-field training formats to improve offside decision making. One group trained with video simulations and another with computer animations. Feedback after every offside situation allowed assistant referees to compensate for the consequences of the flash-lag effect and to improve their decision-making accuracy. First, response accuracy improved and flag errors decreased for both training groups implying that training interventions with feedback taught assistant referees to better deal with the flash-lag effect. Second, the results demonstrated no effect of format, although assistant referees rated video simulations higher for fidelity than computer animations. This implies that a cognitive correction to a perceptual effect can be learned also when the format does not correspond closely with the original perceptual situation. Off-field offside decision-making training should be considered as part of training because it is a considerable help to gain more experience and to improve overall decision-making performance.  相似文献   

Abilities and skill acquisition: A latent growth curve approach     

Manuel C. Voelkle  Werner W. Wittmann  Phillip L. Ackerman 《Learning and individual differences》2006,16(4):303-319

The relationship between abilities and skill acquisition has been the subject of numerous controversies in psychology. However, while most researchers implicitly or explicitly accept the idea that abilities and skill acquisition should be related, empirical research has failed to provide evidence for a consistently strong correlation between the two constructs. Based on the reanalysis of a study on skill acquisition using the air traffic controller task TRACON [Ackerman, P. L., Kanfer, R., and Goff, M. (1995). Cognitive and Noncognitive Determinants and Consequences of Complex Skill Acquisition. Journal of Experimental Psychology. Applied, 1(4), 270–304], it will be shown how latent growth curve modeling can help to gain a better understanding of the relationship between human abilities and skill acquisition. A brief introduction into the basic concepts of latent growth curve modeling will be given, particularly with regard to the advantages for the analysis of skill acquisition and its determinants. The goal is thereby to provide evidence for a much closer association than commonly assumed and to offer a new, differential, perspective formerly obscured by traditional between-subject analyses.  相似文献   

The relative age effect in youth soccer across Europe   总被引：2，自引：2，他引：0  

Helsen WF  van Winckel J  Williams AM 《Journal of sports sciences》2005,23(6):629-636

The potential asymmetries in the birth-date distributions of youth soccer players across ten European countries (2175 age citations) were considered. First, we examined the birth-dates of players representing national youth teams in international competitions. Second, the birth-dates of players representing professional club teams in international youth tournaments were analysed. Kolmogorov-Smirnov tests were used to assess differences between observed and expected birth-date distributions. Regression analyses were employed to examine the relationship between month of birth and number of players in the different samples. The results showed an over-representation of players born in the first quarter of the selection year (from January to March) for all the national youth selections at the under-15 (U-15), U-16, U-17 and U-18 age categories, as well as for the UEFA U-16 tournaments and Meridian Cup. Players with a greater relative age are more likely to be identified as "talented" because of the likely physical advantages they have over their "younger" peers. Some options for reducing the relative age effect are offered.  相似文献