The role of path length- and speed-related factors for the enhancement of section performance in alpine giant slalom     

Jörg Spörri  Josef Kröll  Hermann Schwameder  Erich Müller 《European Journal of Sport Science》2018,18(7):911-919

Knowing how to enhance alpine skiing performance is essential for effective coaching. The purpose of this study was to explore the role of path length- and speed-related factors for performance enhancement, while skiing on a homogeneously set/constantly inclined giant slalom course section (average gate distance: 27?m; offset: 8?m; slope inclination: 26°). During a video-based three-dimensional kinematic field-experiment, the data of six athletes who skied a two-gate section on four different types of skis were collected. The performance parameter analysed was section time. The performance predictors analysed were centre of mass (CoM), path length and the change in specific mechanical energy per entrance speed along the analysed section. Furthermore, since the current study examined alpine skiing performance within short sections, the skier’s entrance speed was also considered. Classified as a high-performance and a low-performance group based on section time, slow and fast trials significantly differed in CoM path length, the change in specific mechanical energy per entrance speed and entrance speed. The entrance speed of all trials analysed ranged between 15.25 and 17.66?m/s. In trials with both high and low entrance speed, the change in specific mechanical energy per entrance speed was found to be more relevant for the prediction of section time than CoM path length. However, further studies should investigate whether such a prioritization can be unrestrictedly generalized to other situations, such as entrance speeds, course sets, slope inclinations and competition disciplines different to those assessed in the current study.  相似文献   

Kinematic analysis of proximal-to-distal and simultaneous motion sequencing of straight punches     

Philip Xaver Fuchs  Stefan Josef Lindinger  Hermann Schwameder 《Sports biomechanics / International Society of Biomechanics in Sports》2018,17(4):512-530

Consecutive proximal-to-distal sequencing of motion is considered to be integral for generating high velocity of distal segments in many sports. Simultaneous usage of proximal and distal segments as seen in martial arts is by far less well investigated. Therefore, the aim of the study was to characterise and differentiate the concepts of consecutive (CSM) and simultaneous (SSM) sequence of motion in straight reverse punches as practised in Practical Wing Chun. Four experienced martial artists succeeded an eligibility test for technical proficiency in both concepts and performed a total number of 20 straight punches per concept. Eight MX13 Vicon cameras (250 fps) and Visual3D were used for motion capture and analyses. Both motion concepts showed proximal-to-distal sequencing of maximal joint velocities but, in SSM, this was coupled with simultaneous initiation. Key characteristics were: high pelvis momentum and backswing of shoulder and elbow (CSM); and importance of shoulder involvement (SSM). Different ranges of motion, timing aspects and achieved maximal angular velocities distinguished both concepts, which led to differences (p < 0.05) in fist velocity at contact, execution time, distance and horizontal shift of the centre of mass. Proper application of both concepts depends on the environmental setting, situational requirements and individual fighting style.  相似文献   

Teaching OO Software Engineering by Example: The Games Factory     

Hermann Hu;auni  Igor Metz 《Computer Science Education》2013,23(1):111-121

Object‐oriented analysis, design, and programming is a software development technology which has attracted universal attention in the past few years. We do not think that object‐oriented technology is a completely new approach to software construction; it is merely the consequent continuation of software engineering principles which have evolved since 1968, the year of the birth of software engineering. This article describes a course on software engineering with objects which track the evolution of this discipline. We work through the history of these concepts using a single application domain, demonstrating how the relevant analysis and design methods evolved over time, culminating in object‐oriented techniques.  相似文献   

Reviews     

Peter E. Kane  Alan S. Kaye  Dennis R. Klinzing  Dennis R. Klinzing  Fred E. Jandt  Hermann G. Stelzner 《Communication quarterly》2013,61(1):50-55

FREEDOM SPENT. By Richard Harris. Boston: Little, Brown and Company, 1976; pp. 460. $12.95.

MALE/FEMALE LANGUAGE, WITH A COMPREHENSIVE BIBLIOGRAPHY. By Mary Ritchie Key. Metuchen, New Jersey: Scarecrow Press, 1975; pp. vii + 200; $7.95.

CONTEMPORARY SPEECH: A COMPREHENSIVE APPROACH TO COMMUNICATION. Compiled by Mary Frances Hopkins and Beverly Whitaker. Edited by Bernard Brommel. Skokie, IL: National Textbook Company, 1976; pp. ix + 316. $11.

COMMUNICATING. By Anita Taylor, Teresa Rosegrant, Authur Meyer, and B. Thomas Samples. Englewood Cliffs, NJ: Prentice‐Hall, Inc., pp. xiii + 466. $9.95.

MASTERING CLASSROOM COMMUNICATION: WHAT INTERACTION ANALYSIS TELLS THE TEACHER. By Dorothy Grant Hennings. Pacific Palisades, California: Goodyear Publishing Company, 1975; pp. xiii + 193. $5.95.

THE RHETORIC OF WESTERN THOUGHT. By James L. Golden, Goodwin F. Berquist, and William E. Coleman. Dubuque, Iowa: Kendall/Hunt, 1976; pp. 272. Paper $9.95.  相似文献   

xyZET: A Simulation Program for Physics Teaching   总被引：1，自引：1，他引：0  

Härtel  Hermann 《Journal of Science Education and Technology》2000,9(3):275-286

A simulation program, named xyZET, has been developed to support the teaching of physics and the preparation of interesting and challenging exercise material. xyZET offers a rich and complex user interface, which allows the development in 3D-space of numerous experiments in basic mechanics and electricity. It is also possible to visualize effects dependent upon relativistic changes of mass. In addition, the radiation of accelerated charge carriers can be demonstrated in accordance with the Linard Wiechert theory. A special learner mode has been implemented as an alternative to the normal working environment in which all the control elements are available to the user. In this learner mode, the program can be controlled by Java applets embedded in WEB pages. By clicking on active buttons, communication with the simulation program is established, using the TCP/IP protocol. This allows the learner to concentrate fully on the topic, and frees him or her from any control activity which might divert attention from the underlying science. Using xyZET and this external control feature a complete mechanics course has been developed, containing most of the traditional topics taught in 11th grade at German high schools (Gymnasium). The course material has been tested under classroom conditions and proven to be stable and effective. Further improvements can be expected if students have access to more powerful computers and more support and time is provided to allow exploratory and self-supported learning. xyZET was developed under UNIX and X-windows and runs on PC platforms under LINUX or Windows95/98.  相似文献   

Book reviews     

Reinhard Bendix  G. de Landsheere  Hermann Röhrs  Christian Kluth  Menachem Gerson  Christine Laconte  Elliot W. Eisner  Ludwig Liegle  Françoise Bacher  Cesar Birzea  A. Harry Passow  G. F. Peaker  Jerry Norman Haar  Paul E. Peterson  Nigel Grant  Bom Mo Chung  Klaus Schleicher  Philip G. Altbach  T. Neville Postlethwaite  Tessa Blackstone 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1973,19(2):262-298

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Book Reviews     

Brian Holmes  John Downing  Eva Holmes  Gilbert de Landsheere  Hermann Rademacker  Saul B. Robinsohn  Carl -Gunnar Janson  John Biggs  Neville Postlethwaite  Ingegerd Axén  Esa Santala  Harold Wyndham 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1965,11(3):360-378

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Steps     

Hermann Hesse 《The Educational forum》2013,77(2)

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Responsibilities and Problems of International Education   总被引：1，自引：0，他引：1  

Hermann Röhrs 《比较教育学》1970,6(2):125-135

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Dimensionen und Visionen des Sports: Evaluation — Profilbildung — Globalisierung     

Hermann Müller  Michael Nagel  Siegfried Nagel 《Sportwissenschaft》2000,30(1):103-108

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