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31.
在阐述了青岛帆船体育旅游市场供给、客源市场、市场传播的总体状况的基础上,探讨了青岛市主动帆船旅游、帆船赛事旅游、怀旧帆船旅游3种主要类别帆船体育旅游的现状,同时针对现阶段青岛市帆船体育旅游业存在的问题进行分析,并提出了相应的改进措施。 相似文献
32.
针对过河问题中出发点与码头所成夹角的不同情况建立微分方程模型,求出过河路径,并对行船方向、船速和水速之间的关系进行分析. 相似文献
33.
Abstract The aim of this study was to describe the injuries sustained by an America's Cup crew during eight preparatory competitions of the 32nd America's Cup 2007 and the Louis Vuitton Cup (from October 2004 to June 2007). The anatomical location, type of injury, and mechanism of injury were recorded. The injuries were categorized based on each sailor's position on the boat according to three intensities of physical demands. The injury rates per sailor and per 1000 h of competition were determined. In total, 90 injuries were registered. The overall incidence was 10 injuries per 1000 competition hours. Overuse injuries accounted for 76.6% of all lesions. The most common anatomical location of injuries was the upper limb (36.6%), followed by the upper dorsal and cervical spine (34.4%). Frequency of injury was related to the sailor's position on the boat, being higher in the group with more demanding activities (grinder, bowman, and mastman). Most injuries (67%) were sustained by this group of sailors. The most common injuries in this group were muscle contractures of the quadratus lumborum (11), trapezius (8), and rhomboid (7). There were eight cases of elbow epicondylitis, four cases of tendinopathy of the supraspinous tendon, and three cases of tendinopathy of the biceps brachii. An America's Cup yachting crew is exposed to a high risk of overuse injuries, especially those sailors whose boat position involves high-intensity activity. 相似文献
34.
This paper describes current progress made towards the realization of a match-racing simulator. The aim of the project is
to be able to simulate and to modify typical situations while introducing quantifiable data for strategic and tactical analysis.
The fundamental model consists of six fully coupled equations of the dynamics of two boats. The largest possible number of
variables is taken into account, even though some are initially approximations. The influences of the three attitude angles
on the hydrodynamic forces are taken into account using the ‘experiment planning method’ applied to towing-tank tests. For
the aerodynamics, empirical models (for example IMS) are adopted. The interaction between the two boats is obtained by representing
the sail perturbation by means of a single horseshoe vortex and a self-preserved viscous plane wake. The simulator has a modular
structure, which allows the progressive improvement of each part as studies and knowledge advance. Comparisons with calculations
of three-dimensional flows and with wind tunnel measurements validate the interaction model. The results presented show a
satisfactory agreement with the polar velocity diagram available for the studied boat, even if more reliable trials at sea
are needed, with measurements of boat behaviour, wind and sea state. Simulations allow us to quantify the relative influence
of model coefficients on boat behaviour. Thus it is possible to identify which factors must be improved first. Tacking simulations
are used to illustrate this possibility. To conclude, an example of the practical use of the simulator is presented by comparing
two tactical scenarios for the final part of the upwind leg. 相似文献
35.
在帆船比赛中,规则是技、战术的灵魂,规则严格制约着技术,遵守规则并运用规则实施战术才是运动员应有的能力。在项目的发展历程中,规则与技战术的发展是相互促进和制约的,合理的规则是该项目得以发展壮大的原动力。通过对帆船规则的解读,分析了国内对帆船规则的错误认识的几种表现,总结了帆船规则与技、战术及遵守规则与利用规则的关系。 相似文献
36.
对国家帆船队男子激光级两名重点运动员的研究发现,施某主要存在核心力量及高强度运动下腿部肌肉耐力不足,而乔某主要是由于腰肌劳损导致在进行高强度运动时出现腰部酸痛、僵硬、腰椎活动度减弱等问题。根据两者的不同状况,针对性的制定各自的训练方案,通过3~4周的训练后,运动员的运动能力及损伤恢复情况均有所改善。通过高水平运动员体能训练计划制定、实施,改善运动员的运动能力,完善有效提高帆船运动员专项体能训练的手段与方法。同时,通过对重点运动员损伤后的康复训练,汲取康复体能训练有效手段,探索运动损伤机制并在训练中积极预防损伤。 相似文献
37.
The hypothesis, that sailing upwind in wind speeds above 12 knots causes fatigue, which manifests as a reduction in exerted hiking strap force and/or maximal isometric voluntary contraction force (MVC) of the knee extensors, was evaluated. Additionally, it was investigated if a relationship exists between maximal exerted hiking force (hMVC) and sailing performance. In part 1 of the study, 12 national level athletes sailed upwind for 2?×?10?min while hiking strap forces were continuously acquired. Before, in between and after sailing periods, the MVC of the knee extensors was measured. In part 2 of the study, hMVC was measured dry land in a hiking bench and correlated with the overall results at a national championship. Hiking strap force decreased from the first to the last minute in both 10?min sailing periods (430?±?131 vs. 285?±?130?N, P?<?.001 and 369?±?74 vs. 267?±?97 N, P?<?.001, respectively), but MVC was similar before, between and after the two 10?min sailing periods (878?±?215 vs. 852?±?202 vs. 844?±?211 130?N). In part 2, a significant positive correlation (r2?=?0.619, P?<?.01) was observed between hMVC and regatta results. In conclusion, upwind sailing in wind speeds above 12 knots causes sailing-specific fatigue as evidenced by a marked reduction in exerted hiking strap force. However, MVC of the knee extensors was not compromised ～45?s after hiking was terminated. Additionally, sailing performance is related to maximal hiking force. 相似文献
38.
39.
为弥补现有船舶电子海图导航系统不能进行航线自动规划的不足,通过整理《中国航路指南》中的转向点,建立转向点关系库,进而形成中国沿海主要港口间的航线网络.利用静态路网中求解最短路径的A*算法,引入恒向线航法计算公式作为A*算法的启发式函数,设计并实现中国沿海主要港口推荐航线算法.实验结果表明,A*算法能够有效、便捷地规划出船舶航行的安全航线.该算法可应用于电子海图显示与信息系统(Electronic Chart DisplayInformation System,ECDIS)等,可为我国沿海航行的船舶自动推荐《中国航路指南》中的航线,给船舶航行提供参考,对科学航海、船舶安全航行和船员减压等具有实践意义. 相似文献
40.
在原有的基础上，将中分纬度航法推广应用到解决跨赤道航行方面，并设计和计算出全新的中分纬度航法改正率表。 相似文献