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Limb symmetry index in competitive alpine ski racers:Reference values and injury risk identification according to age-related performance levels

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Journal of Sport and Health Science 2018年第4期7卷 405-415页

作者： Lisa Steidl-müller Carolin Hildebrandt erich müiller Christian Fink Christian Raschner Department of Sport Science University oflnnsbruekInnsbruck 6020Austria Department of Sport Science and Kinesiology University of SalzburgSalzburg 5400Austria Research Unit for Orthopedic Sports medicine and Injury Prevention Institute of Psychology（ISAG）The Health ＆ Life Sciences University（UMIT）Innsbruck 6020Austria Gelenkpunkt-Sports and Joint Surgery Innsbruck 6020Austria Corresponding author.E-mail address：lisa.steidl-mueller@uibk.ac.at

Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. methods： The study （Study 1） included 285 high-level competitive ski racers （125 females, 160 males） of 3 age-related performance levels and based on the school system： 95 youth （10-14 years, secondary modem school）, 107 adolescent （15-19 years, grammar school）, and 83 elite athletes （20-34 years）. To investigate the second aim （Study 2）, 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests （strength related： one-leg counter movement jump （OL-CmJ） and one-leg isometric/isokinetic press strength test （OL-ILS）; coordination related： one-leg stability test （OL-ST） and one-leg speedy jump test （OL-SJ））. The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results： There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests： the OL-CmJ （X^2（2, 285） = 9.09; p = 0.01） and the OL-ILS （X^2（2,285） = 14.79; p 〈 0.01）. The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers （Wald = 7.08; p 〈 0.01）. No significant risk factors were found for overuse injuries. Conclusion： Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically discussed. It seems to be necessary to defi

关键词： Age-related performance levels Alpine ski racing Injury risk Limb differences Youth athletes

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Using coalgebras and the Giry monad for interpreting game logics a tutorial

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Frontiers of Computer Science 2017年第6期11卷 948-970页

作者： Ernst-erich DOBERKAT math++ Software Bochum 44879 Germany

The stochastic interpretation of Parikh＇s game logic should not follow the usual pattern of Kripke models, which in turn are based on the Kleisli morphisms for the Giry monad, rather, a specific and more general approach to proba- bilistic nondeterminism is required. We outline this approach together with its probabilistic and measure theoretic basis, in- troducing in a leisurely pace the Giry monad and its Kleisli morphisms together with important techniques for manipu- lating them. Proof establishing specific techniques are given, and pointers to the extant literature are provided. After working through this tutorial, the reader should find it easier to follow the original literature in this and related areas, and it should be possible for her or him to appreciate measure theoretic arguments for original work in the areas of markov transition systems, and stochastic effectivity func- tions.

关键词： coalgebras modal logics monads Giry monad,upper closed monad composition of monads game logics

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Performance and safety in elite skiing sports:A big challenge on specificity,individuality,and complexity

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Journal of Sport and Health Science 2018年第4期7卷 379-380页

作者： erich muller Yu Liu Department of Sport Science and Kinesiology University of SalzburgSalzburg A-5020Austria Key Laboratory of Exercise and Health Sciences of ministry of Education Shanghai University of SportShanghai 200438China

Winter sports, including those with a focus on gliding with skis on snow, have become extremely complex in the last few decades. During the Olympic Games held in Pyeongchang, Republic of Korea, in 2018, a greater number of different skiing competitions took place： alpine skiing with giant slalom, downhill, slalom, and super-G and alpine combined; biathlon with 10-km sprint, 12.5-km pursuit, 15-km mass start, 20-km individual, and a 4×7.5-km relay; cross-country skiing with 6 different kinds of races including short, medium and long distances, classical and skating techniques, and individual and mass start; free-style skiing with aerials, moguls, ski cross, ski halfpipe, and ski slopestyle; Nordic skiing combined with ski jumping on large and normal hills, followed by cross-country skiing over 10 km; and snowboard with big air, half pipe, parallel giant slalom, slope style, and snowboard cross.

关键词：滑雪运动复杂性特性安全性能个性冬季运动滑雪板

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Plasma Spray Forming of Nanostructured Composite Coatings

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Journal of materials Science & Technology 2002年第3期18卷 287-288页

作者： XianliangJIANG erich.Jordan 等 InstituteofSurfaceandCoatingsTechnology CentralSouthUniversityChangsha410083China InstituteofmatrialsScience UniversityofConnecticutStorrsCT06269USA

The nanostructure composite coating is obtained via plasma spraying of Al2O3-13 wt pct TiO2 powder. Brittle and hard lamella results from melted nanostructured powder. Ductile nanostructured matrix forms from unmelted nanostructured particles. Through the adjustment of constituent and nanostructure, hardness/strength and toughness/ductility are balanced and overall properties of the structure composite are achieved.

关键词： Plasma spray forming Nanostructured coating mechanical Property

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A NOTE ON PRESSURE APPROXImATION OF FIRST AND HIGHER ORDER PROJECTION SCHEmES FOR THE NONSTATIONARY INCOmPRESSIBLE NAVIER-STOKES EQUATIONS

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Journal of Computational mathematics 2009年第2期27卷 338-347页

作者： erich Carelli Andrcas Prohl mathematisches Institut Universitt TübingenAuf der Morgenstelle 10D-72076 Tübingen

Projection methods are efficient operator-splitting schemes to approximate solutions of the incompressible Navier-Stokes equations. As a major drawback, they introduce spurious layers, both in space and time. In this work, we survey convergence results for higher order projection methods, in the presence of only strong solutions of the limiting problem; in particular, we highlight concomitant difficulties in the construction process of accurate higher order schemes, such as limited regularities of the limiting solution, and a lack of accurate initial data for the pressure. Computational experiments are included to compare the presented schemes, and illustrate the difficulties mentioned.

关键词： Incompressible Navier-Stokes equation Time discretization Projection method

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A combined method to model grain crushing with DEm

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Geoscience Frontiers 2020年第2期11卷 451-459页

作者： Jia Lin erich Bauer WeiWu Institute of Geotechnical Engineering University of Natural Resources and Life SciencesViennaAustria Institute of Applied mechanics Graz University of TechnologyGrazAustria

This paper presents a combined method to model grain crushing effects with discrete element *** method combines the two most commonly used concepts to model grain crushing in DEm,*** replacement method and the agglomerate method,so that it is both accurate and *** method can be easily *** performance is shown by several DEm simulations of biaxial *** with different crush-abilities are *** simulation results with and without grain crushing are compared and *** change of grain size distribution due to grain crushing is also investigated.

关键词： Grain crushing Discrete element method Granular material

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“When you’re down, stay down”:A lesson for all competitive alpine skiers supported by an ACL rupture measured in vivo

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Journal of Sport and Health Science 2022年第1期11卷 14-20页

作者： Jörg Spöorri erich müller Josef Kröoll Sports medical Research Group Department of OrthopaedicsBalgrist University HospitalUniversity of ZurichZurich 8008Switzerland University Centre for Prevention and Sports medicine Department of OrthopaedicsBalgrist University HospitalUniversity of ZurichZurich 8008Switzerland Department of Sport Science and Kinesiology University of SalzburgHallein-Ri 5400Austria

Background:During an experiment,a ski racer equipped with various measurement devices suffered an anterior cruciate ligament(ACL)rupture in his right *** aim of this study was to describe the underlying injury mechanism from a functional ***:Eight giant slalom turns(i.e.,4 left turns),followed by 1 left turn at which the ACL injury occurred,were recorded by 2 video cameras,electromyography of 4 relevant muscle groups,inertial measurement units to measure knee and hip angles,and pressure insoles to determine ground reaction ***:Due to a loss of balance,the ski racer began to slide sideways at the apex of a left *** sliding,his right(outside)leg was actively abducted upward without touching the *** ski racer then attempted to stand up again by dropping his leg back towards the snow *** end of this dropping was accompanied by a decrease in electromyographic activity in the knee stabilizing *** the inside edge of the outer ski caught the snow surface,a rapidly increasing peak force,knee flexion,and an aggressive sudden activation of the vastus medialis muscle were observed,while biceps femoris and rectus femoris further decreased their activation *** likely resulted in excessive anterior translation of the tibia relative to the femur,causing damage to the ***:Our example emphasizes that ski racers should not get up until they stop ***:“When you’re down,stay down.”

关键词： Alpine skiing Athletes Injury mechanism Injury prevention Knee injuries

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Strength, deformability and permeability of kakiritic rocks from the Gotthard base tunnel

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Journal of Rock mechanics and Geotechnical Engineering 2023年第9期15卷 2224-2237页

作者： martin Vogelhuber erich Pimentel Georgios Anagnostou ETH Zurich ZurichSwitzerland

The 57-km long,new Gotthard Base Tunnel(GBT)crosses over a 1.1-km long stretch containing kakirites,*** rocks which,depending on the degree of tectonisation,may exhibit severe squeezing behaviour upon tunnel *** tunnel stretch was already identified as a key problem in the early planning phase,necessitating intensive geological exploration and laboratory investigations over a 14-year period,including research and development in experimental *** laboratory investigations for the GBT provided not only a considerable amount of data about the geotechnical parameters of the kakirites,but also valuable information about their basic behaviour and the adequacy of various testing techniques for this type of ***,by using specially designed testing equipment and procedures,it was shown that,(1)conventional rock mechanics triaxial tests cannot provide reliable results for kakirites;(2)the kakirites obey the principle of effective stress in Terzaghi’s classical form and consequently it is indispensable to measure the pore pressure during triaxial testing,analogously to the consolidated drained(CD)and consolidated undrained(CU)tests in soil mechanics;(3)the effects of a possible loss of water and desaturation during sampling,transport,storage and preparation of specimens can be successfully mitigated by subjecting the specimens to flow-through before the actual triaxial testing;and,(4)CD tests on partially saturated specimens that are obtained by means of flow-through can provide reliable and reproducible *** saves a significant amount of time,allows a greater number of tests to be performed,and allows results to be obtained more quickly,which is particularly important for decision-making during tunnel advance.

关键词： Squeezing Pore pressure Triaxial testing

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Beijing 2022 Winter Olympic Games:Commitments to science and public health

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Journal of Sport and Health Science 2022年第1期11卷 1-2页

作者： Yu Liu Barbara E.Ainsworth erich müller Key Laboratory of Exercise and Health Science of ministry of Education Shanghai University of SportShanghai 200438China Barbara E.Ainsworth Guest Editor School of KinesiologyShanghai University of SportShanghai 200438China Department of Sport Science and Kinesiology University of SalzburgSalzburg5400Austria

The Beijing 24th 2022 Winter Olympic Games present a unique opportunity to promote the spirit and values of the Olympic Games in relation to their impact on physical activity and global health,sports medicine,and sports *** 2022 Winter Olympic Games mark the 98th year since the first Winter Games were held in Chamonix,France,in *** inaugural Winter Olympic Games sponsored 16 events,and 250 athletes from 16 nations participated.1 In contrast,the Beijing 2022 Winter Olympic Games will sponsor 109 events.

关键词： Winter Games sports

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Prospects and challenges of silicon/germanium on-chip optoelectronics

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Frontiers of Optoelectronics 2010年第2期3卷 143-152页

作者： erich KASPER Institute of Semiconductor Engineering University of Stuttgart

On-chip optoelectronics allows the integration of optoelectronic functions with microelectronics. Recent advances in silicon substrate fabrication(silicon-oninsulator（SOI）) and in heterostructure engineering（SiGe/Si） push this field to compact（chipsize） waveguide systems with high-speed response（50-GHz subsystems realized, potential with above 100 GHz）. In this paper, the application and requirements, the future solutions, the components and the physical effects are discussed.A very high refractive index contrast of the waveguide Si-core/SiO2-cladding is responsible for the submicron line widths and strong bendings realized in chipsize waveguide lines and passive devices. The SiGe/Si heterostructure shifts the accessible wavelength into infrared up to telecommunication wavelengths 1.30–1.55 μm. Germanium, although also an indirect semiconductor as silicon,offers direct optical transitions which are only 140 meV above the dominant indirect one. This is the basic property for realizing high-speed devices for future above 10 GHz on-chip clocks and, eventually, a laser source monolithically integrated on the Si substrate.

关键词： optoelectronics semiconductor circuit silicon germanium silicon-on-insulator (SOI) photodetector modulator waveguide quantum confined Stark effect (QCSE)

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