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1.
The purpose of this study was to develop a portable force measurement system for ice hockey skating. The system consisted of three strain gauge pairs affixed to an ice hockey skate’s blade holder with wire leads connected to a microprocessor controlled data acquisition device carried in a backpack worn by the skater. The configuration of the strain gauges simultaneously determined the vertical and medial–lateral force components experienced by the blade holder with a resolution accuracy of 1.9 N and a coefficient of variation of 9.2%. On-ice testing of this system with subjects performing forward start, acceleration, and constant velocity skating permitted unencumbered, natural movement and demonstrated clear, unambiguous signal responses, high trial-to-trial repeatability, and easy data retrieval. The practicality and accuracy of this testing approach have many applications, such as a quantitative tool for skating force assessment to aid athletes and coaches, as well as providing the means to examine other skill-specific dynamics.  相似文献   
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Book reviews     
Association of Research Libraries  相似文献   
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Empirical research provides evidence that electronic communication does not change government agencies into post-bureaucratic organizations. Structuration Theory is used to explore the interaction between e-mail use, communication patterns of civil servants, and two bureaucratic characteristics: formalization and hierarchy. Previous research suggested that the use of e-mail leads to less formalization and less hierarchy, but empirical research in three bureaucratic organizations in the Netherlands leads to different conclusions. First, the use of e-mail leads to informal formalization: the style of communication is more informal but the content focuses less on personal issues and emphasizes efficient recordings of agreements. Second, the use of e-mail leads to hierarchical horizontalization: horizontal contacts take a more central position in bureaucratic organizations but these horizontal contacts are tightly linked to vertical structures. The result of the interaction between e-mail and government bureaucracy is horizontal communication directly linked to vertical structures. Electronic communication turns government agencies into late-bureaucratic organizations.  相似文献   
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Among the huge maze of resources available on the Internet, UnCoverWeb stands out as a valuable tool for medical libraries. This up-to-date, free-access, multidisciplinary database of periodical references is searched through an easy-to-learn graphical user interface that is a welcome improvement over the telnet version. This article reviews the basic and advanced search techniques for UnCoverWeb, as well as providing information on the document delivery functions and table of contents alerting service called Reveal. UnCover's currency is evaluated and compared with other current awareness resources. System deficiencies are discussed, with the conclusion that although UnCoverWeb lacks the sophisticated features of many commercial database search services, it is nonetheless a useful addition to the repertoire of information sources available in a library.  相似文献   
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Zusammenfassung. Information ist der wichtigste Grundbegriff der Informatik. Ein semantischer Ansatz erklärt Information als Bedeutung einer Nachricht für ihren Empfänger. Als Folge davon hängt der Informationsgehalt einer Datei, einer Datenbank, eines Buches oder eines Filmes von der Interpretation ab, die ein Nutzer vornehmen kann oder gerade vornimmt. Informationsmaße werden sowohl von der Lesbarkeit einer Nachricht als auch von der Qualität des Interpreten bestimmt. Information kann neu entstehen, verloren gehen oder verändert werden.CR Subject Classification: E.4, H.1  相似文献   
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Our study compares the motivations of Australian and German book publishers. The results demonstrate remarkable similarities, but also a significant difference regarding the effects of the publishers’ self-concept. In the German case the publishers with a dominant economic orientation are more proactive than the publishers with a dominant cultural orientation. In the Australian case, this correlation does not exist. The same difference holds for the relationship between the economic orientation and extrinsic motivation. We discuss these results and examine empirical evidence and theoretical suggestions to explain the differing findings. The data stem from surveys conducted in the two countries with responses of 196 (Germany) and 54 publishers (Australia).  相似文献   
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The aim of this study was to evaluate the predictive potential provided by two ventilatory inflection points (VIP1 and VIP2) examined in field without using gas analysis systems and uncomfortable facemasks. A calibrated respiratory inductance plethysmograph (RIP) and a computerised routine were utilised, respectively, to derive ventilation and to detect VIP1 and VIP2 during a standardised field ramp test on a 400 m running track on 81 participants. In addition, average running speed of a competitive 1000 m run (S1k) was observed as criterion. The predictive value of running speed at VIP1 (SVIP1) and the speed range between VIP1 and VIP2 in relation to VIP2 (VIPSPAN) was analysed via regression analysis. VIPSPAN rather than running speed at VIP2 (SVIP2) was operationalised as a predictor to consider the covariance between SVIP1 and SVIP2. SVIP1 and VIPSPAN, respectively, provided 58.9% and 22.9% of explained variance in regard to S1k. Considering covariance, the timing of two ventilatory inflection points provides predictive value in regard to a competitive 1000 m run. This is the first study to apply computerised detection of ventilatory inflection points in a field setting independent on measurements of the respiratory gas exchange and without using any facemasks.  相似文献   
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