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21.
在可预见的未来一段时期内,航运市场运力供需失衡会呈现常态化,集装箱运力供给会长期大于运力需求,是否减速航行和闲置运力成为航运企业的关键决策.基于这一行业发展背景,以航速和运营船舶数量为决策变量,构建运力过剩时集装箱班轮航线运力配置数学优化模型.结合问题的特性开发禁忌搜索算法,对模型进行求解.基于实际航线的大规模数值算例进行试验.试验结果显示模型及算法有效,表明该模型和算法对运力供需失衡时运力配置决策具有借鉴意义. 相似文献
22.
郭先登 《青岛职业技术学院学报》2009,22(1)
青岛成功举办奥帆赛和残奥帆赛,树立了世界重要城市的新形象,强化了品牌城市的比较优势,奥帆赛和残奥帆赛软硬件共同作为一项巨大的人文遗产留给了城市,转化为城市长期深入改革开放的巨大推动力.青岛成功举办奥帆赛和残奥帆赛的实践,进一步创新了现代奥运经济发展的模式,完善了现代奥运经济形态;极大地推动了奥运经济、奥帆经济的发展,使奥运经济长期持续地成为城市经济发展的一个重要组成部分. 相似文献
23.
Stewart T. Cotterill Hazel Brown 《Journal of Adventure Education & Outdoor Learning》2018,18(3):227-241
Research evidence suggests that outdoor education offers significant potential in priming healthy physical activity behaviors, developing life skills, enhancing self-esteem and promoting improved academic performance. The aim of the current study was to explore from a cross-sectional perspective the perceived benefits of a dinghy sailing program on 9–13-year-old school children. Participants (n = 38) were drawn from a diverse range of relevant participation and stakeholder groups, including school children, teachers and sailing instructors. Semi-structured interviews (adults) and focus groups (children) were used to collect data, with inductive data analysis methods applied. Six superordinate themes arose from the data highlighting physical and mental health benefits as well as the potential to development key life skills, self-esteem and the possible interaction with other aspects of the school curriculum to enhance student learning. 相似文献
24.
充分运用Mathematica数学软件，通过小三角插值法、曲面拟合及不可航行线组合，最终得到一幅可知危险度的港湾可航行区域图。 相似文献
25.
采用多学科相结合的研究方式,以上海帆船项目备战2012年伦敦奥运会的重点运动员为研究对象,伦敦帆船比赛场地环境、特征测试与分析为研究核心,对运动员个体化技术诊断与分析、不同训练阶段机能状态监控方法、专项训练质量监控方法、伤病预防治疗与康复、训练过程与赛前心理调控、体能训练方法研究与监控、膳食与营养监控和体育科技信息分析等多方面进行综合攻关研究与服务。基本建立了上海帆船项目重点运动员备战伦敦奥运会综合科技服务保障平台,并逐步把研究成果应用于整个备战过程,提高训练效益,提升体育科技的实践能力,为上海帆船项目实现在伦敦奥运会争金夺牌的目标提供有力的科研支撑和科技保障。 相似文献
26.
Simon Pearson Patria Hume David Slyfield John Cronin 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(1):71-80
The reliability of grinding performance was assessed in 18 current Emirates Team New Zealand America's Cup sailors in two test sessions separated by 5 h using a custom-built ergometer. Sixteen different grinding conditions that varied by load (Light 39 N·m, Moderate 48 N·m, Heavy 68 N·m), deck heel (Flat 0° control, Downhill 25°, Uphill 25°, Right 25°, Left 25°), and grinding direction (forwards, backwards) were assessed using peak power and external work over 5 s during maximal-effort 8-s grinds. Reliability statistics included the difference in mean (Mdiff), standard error of measurement (SEM), and intraclass correlation coefficients (ICC). External work (SEM = 1.6–6.9%; ICC = 0.91–0.99) was a more consistent performance measure than peak power (SEM = 1.3–9.6%; ICC = 0.84–0.99) across all test conditions. Testing under different load conditions resulted in external work SEMs of 1.6–3.9% with performance more reliable in lighter load conditions. Grinding performance during different heel conditions was less reliable (external work SEMs = 4.6–6.9%). Grinding direction (forward or backward) did not appear to affect performance reliability, although external work was 10–15% higher in forward grinding. Reliability is acceptable across various loads, but testing under different heel conditions may need some protocol development to allow the detection of smaller differences in performance. 相似文献
27.
Neil Wigglesworth 《国际体育史杂志》2013,30(2):145-157
Open-boat sailing boomed in Sydney, Australia, during the 1890s, as a number of new sailing clubs emerged in the city's working waterfront suburbs. Open boats have since been remembered as ‘typically Australian’, radically opposed to the forms and ceremonies of the yachting establishment, and even as sharing the characteristics of the bushman, an archetype of Australian national identity. This article traces the rise of open-boat sailing as a working-class spectator sport and the associated image of an ‘open boat legend’. It argues that open-boat sailing remained a Sydney legend in the 1890s. However, links to working traditions and place have made it possible for popular histories of sailing and yachting to present the open boats and sailors of the period with identifiably Australian characteristics. 相似文献
28.
李文军 《河北能源职业技术学院学报》2013,13(3):70-72
绥中港冬季天气寒冷,海水结冰和淡水浮冰严重,来往于固定航线辽东湾和渤海湾之间船舶,曾多次发生船舱爆裂事故,冬季提前做好防冻措施非常重要。本文是在多年工作经验基础上,总结了冬季防冰的有效措施、航行注意事项及必须的准备工作,为同类船舶处理类似问题提供了有价值的参考。 相似文献
29.
针对海上交通监控中船舶数量众多,且对具有潜在碰撞危险的船舶识别效率不高的问题,提出一种基于DBSCAN(带噪声的基于密度的空间聚类)的船舶会遇实时识别方法。根据海上交通风险监控的研究需求,分析船舶会遇局面的定义。运用墨卡托算法计算船舶之间的距离,采用DBSCAN算法进行船舶会遇聚类识别。基于浙江舟山群岛西南海域航行船舶的AIS数据,对设置不同船舶会遇距离的试验结果进行比较分析,结果表明:当船舶会遇距离为1 n mile时,可以将56艘船划分为7个会遇船舶类,占船舶总数的32.1%,每个会遇船舶类包括2~3艘船。将该方法运用到实际海上交通监控中,可对每个会遇船舶类中的船舶航行动态进行重点关注,降低海上交通监控人员的工作负担,提高海上交通监控的效率。 相似文献
30.
鉴于帆船在离岸航行时仅凭船员经验无法获得长距离最优航线,基于相关航线规划的研究,考虑风场的不均匀性对航线规划的影响,以航行时间最短为目标,建立开敞水域帆船航线规划模型,并设计具有自适应性的遗传算法进行求解。以一艘28英尺的单体龙骨帆船为例验证了模型的可行性和算法的有效性。 相似文献