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重力式码头工程的预制构件一般重量较大,在批量大、规格多的情况下,选择何种搬运工艺,涉及场地布置、设备选用、施工操作人员的劳动强度、搬运效率和经济合理等一系列问题.采用2台轨道电动平车组合搬运3000~5000kN方块的工艺,为重力式码头的构件搬运开辟了新的途径,在港口水工建筑施工中具有广阔的应用前景. 相似文献
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The scattering problem involving water waves by small undulation on the porous ocean-bed in a two-layer fluid,is investigated within the framework of the two-dimensional linear water wave theory where the upper layer is covered by a thin uniform sheet of ice modeled as a thin elastic plate.In such a two-layer fluid there exist waves with two different modes,one with a lower wave number propagate along the ice-cover whilst those with a higher wave number propagate along the interface.An incident wave of a particular wave number gets reflected and transmitted over the bottom undulation into waves of both modes.Perturbation analysis in conjunction with the Fourier transform technique is used to derive the first-order corrections of reflection and transmission coefficients for both the modes due to incident waves of two different modes.One special type of bottom topography is considered as an example to evaluate the related coefficients in detail.These coefficients are depicted in graphical forms to demonstrate the transformation of wave energy between the two modes and also to illustrate the effects of the ice sheet and the porosity of the undulating bed. 相似文献
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随着现代科学信息技术迅猛发展和广泛应用,我国测绘业已基本实现由传统模拟测绘技术体系向数字化、信息化测绘技术体系的跨越.地理信息是一种以采集、贮存、管理、分析和描述整个或部分地球表面空间地理分布有关数据的空间信息,已广泛应用于交通、电力、水利、农林、国土资源、环境保护、金融、电信、地质、矿产、城市建设、教育、人口、海洋以及军事等几十个领域. 相似文献
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2008年4月3日上午。南通中远川崎船舶舾装码头彩旗飘扬,人头攒动,锣鼓喧天。全国政协副主席李金华、政协常委高俊良,交通运输部副部长徐祖远,江苏省副省长张卫国,中远集团总裁魏家福、党组书记张富生等集团领导,日本川崎重工株式会社副社长寺崎正俊以及南通市有关领导.日本川崎重工、中远造船工业公司和业界代表一百余人共同见证了中国首制1万标箱集装箱船——中远大洋洲轮命名交付仪式。 相似文献
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党的十七大文件中第一次提到国家软实力问题。完成中华民族的伟大复兴,在于综合国力的全面提升,而综合国力既包括由经济、科技、军事实力等表现出来的“硬实力”,也包括以文化、意识形态吸引力体现出来的“软实力”。行业软实力是指一个行业以其自身的地位、作用和形象对社会产生的影响力、对公众产生的吸引力和对其他行业产生的仿效力。概括地讲,行业“软实力”包括三个要素,即理念先导力、精神感召力和舆论引导力,其中理念是先导,精神是动力,舆论是环境。 相似文献
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公元前200多年,中国历史上演了有名的一幕:楚汉之争. 当时的情况是楚强汉弱,汉王刘邦连连吃败仗.可是刘邦是块牛皮糖、是个不倒翁,败了就逃,逃了又兜个圈子转回来,再打.楚王项羽受不了,对刘邦说:"不如我们一对一单挑,决个雌雄罢,免得天下百姓再为你我二人白白受苦了!"(愿与王独身挑战,以决雌雄,毋徒令天下父子为也.)刘邦笑了笑,答道:"吾宁斗智,不愿斗力."结果,力能拔山、气可盖世的楚霸王项羽,就这样慢慢被刘邦"耗"死了--流氓出身的刘邦成了汉高祖. 相似文献
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The progress of economic globalization,the rapid growth of international trade,and the maritime transportation has played an increasingly significant role in the international supply chain.As a result,worldwide seaports have suffered from a central problem,which appears in the form of massive amounts of fuel consumed and exhaust gas fumes emitted from the ships while berthed.Many ports have taken the necessary precautions to overcome this problem,while others still suffer due to the presence of technical and financial constraints.In this paper,the barriers,interconnection standards,rules,regulations,power sources,and economic and environmental analysis related to ships,shore-side power were studied in efforts to find a solution to overcome his problem.As a case study,this paper investigates the practicability,costs and benefits of switching from onboard ship auxiliary engines to shore-side power connection for high-speed crafts called Alkahera while berthed at the port of Safaga,Egypt.The results provide the national electricity grid concept as the best economical selection with 49.03 percent of annual cost saving.Moreover,environmentally,it could achieve an annual reduction in exhaust gas emissions of CO2,CO,NOx,P.M,and SO2by 276,2.32,18.87,0.825 and 3.84 tons,respectively. 相似文献
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As a novel type of foundation in beach and shallow sea,the bucket structure is especially suitable for complex conditionssuch as soft clay ground and the worse types of sea environments.In this paper, the bearing capacity of a multi-bucket structure isstudied by experiments with a single bucket and four-bucketfoundation in a saturated sand layer. Based on the experimentaldata and numerical analysis results, the bearing capacity behaviorand the bucket group effect are compared and analyzed.Furthermore, some influential factors, such as the soil type, theratio of length to diameter L/D, the ratio of the bucket spacing tothe bucket diameter S/D, and the bucket number are introduced andtheir effects on the multi-bucket structural capacity are investigatedThe vertical static capacity adjustment factor is introduced toevaluate the bucket group effects of the multi-bucket foundation. 相似文献
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在斜坡堤的设计中,堤心石规格选取关系到工程的实际施工可能性以及工程造价;人工护面块结构类型的选择关系到断面整体稳定性以及块体的使用耐久性;护面块稳定质量计算公式用于人工块体和自然块石时应有不同的要求。规范JTJ 298—1998《防波堤设计与施工规范》中的条文对上述几项内容只进行了简单描述。针对上述内容,对规范JTJ 298—1998的条文提出几点建议。 相似文献
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文中介绍了我国沿海航标管理及维护运行信息化建设的背景,提出了航标信息化建设的设计方案,从设计原则、方法、航标数据库、总体框架等几方面进行论述,从而实现对航标业务及信息数据的规范化、智能化管理。 相似文献
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近期,亚丁湾海域及索马里沿海海盗犯罪成为此海域海上安全的严重威胁。在认清当前海盗犯罪的特点及其成因的基础上,船方必须采取相应的防范和应急处理措施,确保船舶和船员生命安全。 相似文献
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建立了无界大气流场和有界水流场综合作用下的两相球空泡动力学模型,并基于这个模型研究了大气密度和流动对水面空泡溃灭压力的影响机理。结果表明,当空泡收缩到较小时,空泡的非线性动力学行为可以使大气密度或流动对空泡溃灭压力的影响迅速增大,大气密度越小,溃灭压力越大。 相似文献
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针对工程中经常遇到的岩面较高的地质情况,在引桥墩的设计方案中首次采用将墩台分为2级的组合结构。此组合墩台.因缩短力臂从而减小大水平力作用下桩所承受的弯矩,避免以往斜桩难以站稳、普通直桩在水平力作用下产生大弯矩的不足。结合工程实例,介绍组合墩台的结构型式和工程应用情况,并利用大型有限元软件ANSYS建立模型,对桩的位移、内力等进行详细分析。计算结果表明,组合墩台结构型式合理可靠。 相似文献
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基于均匀法的风雨载荷下折叠式舱口盖拓扑优化设计研究 总被引:1,自引:0,他引:1
本文以48500DWT散货船舱口盖为研究对象,提出改变传统折叠式舱口盖设计方法,引入拓扑优化的方法对舱口盖横梁腹板、纵桁腹板进行优化设计。通过ANSYS模拟仿真分析,找出最佳力传递路径的结构布置形式,根据优化结果提取节点信息,经过对拓扑优化后的模型进行二次优化,完善了拓扑优化的结果,使其材料布局形式更合理,研究结果表明,基于均匀法的拓扑优化方法运用于折叠式舱口盖的设计中,可改善舱口盖横梁腹板、纵桁腹板结构,保证其强度并且达到轻量化设计的目的,为舱口盖横梁腹板、纵桁腹板的结构设计提供参考依据。 相似文献
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