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41.
本文根据接触状态下的有限元基本方程,通过对定解条件、约束条件的分析应用,得出了仅与接触点有关的定解方程。 运用所编制的电算程序对某柴油机副连杆销及孔在最大载荷下的失圆变形进行了计算。通过采用空心及实心销两种简化模型计算得出了实际副连杆销的失圆变形范围。 相似文献
42.
Ho-Jin?HwangEmail author Han-Min?Lee Soonhung?Han 《Journal of Marine Science and Technology》2004,9(4):182-189
The selection of marine equipment is a time-consuming process for a ship outfitting designer. The inefficiency originates from the paper-based exchange of design information between shipyards and equipment manufacturers. We propose a method to exchange equipment models for electronic commerce. Shipyard practices were investigated to find out how the outfitting CAD library is being used. We also surveyed international standards for the exchange of digital equipment models, and analyzed the macroparametric methodology. We propose a hybrid method to represent the geometric information using STEP AP203 or the macroparametric method. The nongeometric information is defined according to the Parts Library (PLIB) standard. We implement a pilot system and test it with a ship design data set. The equipment model proposed can be used in the design process with heterogeneous shipbuilding CAD systems. The equipment model can improve the design and purchase process in shipyards. 相似文献
43.
面向21世纪的海事控制理论探讨:船舶营运安全的基本要素结构 总被引:1,自引:0,他引:1
IMO自成立以来始终致力于减少船舶事故。1998年实施的ISM规则和STCW78/95公约,以及即将遍布全球的PSC网,能否有效地降低海事数量?如何控制“人为因素”?如何控制21世纪的海事?经分析,提出了船舶营运安全的基本要素结构:“人-机-环境-管理”理论假说。经检验,假说便于全面查找事故原因和预防措施,便于分析和弥补IMO现行安全措施的不足,方便了海上安全学科体系的构建。进而提出了包含该理论的海事控制策略建议。为将海事控制由经验型的事后性纠正,上升为科学型的事前性预防,提供了一种研究和控制模式 相似文献
44.
ALEXANDROS A. KARAMANLIDIS PANAYIOTIS DENDRINOS ELENI TOUNTA SPYROS KOTOMATAS 《Coastal management》2013,41(3):293-306
Mediterranean monk seal populations have declined dramatically and survive in subpopulations scattered throughout their original distribution. The National Marine Park of Alonnisos, Northern Sporades is the first marine protected Area dedicated to the protection of the species in the Mediterranean. A Monitoring and Awareness Project has been carried out in the area from 1993 to 2000, the results of which have produced a detailed profile of the human usage pattern of the Park and indicated a significant reduction of illegal activities in the area. The pattern of human usage has enabled the monitoring team to adjust their efforts in the Park over time and provided essential baseline data for future management. The combined monitoring and awareness efforts have contributed significantly to the conservation of the Mediterranean monk seal by successfully protecting pupping sites and reducing human-induced mortality of the species in the area. 相似文献
45.
文章通过问卷调查,发现航海类大学生恋爱心理总体健康.恋爱方面存在的问题包括对婚前性行为态度过于开放,困惑于异性选择及交往技巧,在与异性交往中存在自卑感,而对未来职业缺乏规划也导致找对象中存在焦虑等问题,并针对上述问题提出了相应的对策。 相似文献
46.
基于单片机的船舶自动舵模糊控制系统 总被引:2,自引:0,他引:2
该文针对船舶常规自动舵所存在的问题,设计了一种基于自校正模糊控制与Bang-Bang控制相结合的混合控制器,经仿真试验结果表明,加入此混合控制器后,极大地提高了船舶自动舵控制性能。 相似文献
47.
48.
Kary Coleman 《Coastal management》2013,41(2):136-153
The welfare of the marine environment of the U.S. West Coast of California, Oregon, and Washington is hindered by insufficient understanding of ecosystem dynamics and human pressures. Greater coordination, integration, and support of mutually identified research priorities across research organizations on the West Coast are necessary. This level of collaboration is essential to responding to regional ecosystem threats, such as the impacts of human occupation of coastal areas, over-harvesting of marine resources, and climate change. To address this need for collaboration and build on the accomplishments of existing research organizations, this article advocates the establishment of a West Coast regional marine research program (RMRP). 相似文献
49.
Linwood Pendleton 《Coastal management》2013,41(3):239-251
Despite posted warnings and educational campaigns warning about the health risks associated with storm water pollution, swimmers continue to swim in coastal areas polluted by storm water runoff. This study uses a simple spatial model of beach visitation to show how beach amenities and storm drains influence the way in which beach goers choose to locate themselves at beaches in Santa Monica Bay, California. The estimated models indicate that passive means of preventing exposure to marine pollution (e.g., posted signs) could be made significantly more effective if combined with the active management of other beach amenities. Similar methods also could be used to reduce risks to swimmers from other hazards including riptides and boat traffic. 相似文献
50.
为使大型集装箱船舶安全快速地靠离码头,本课题开发研制了3676kW(5000马力)新型全回转拖轮.通过对总体布置和线型的优化设计,合理地选配设备和新工艺的应用,使新型拖轮能安全地进入大型集装箱船舶的艏部和艉部区域,有效地实施顶推作业,提高了作业效率和安全系数,具有显著的经济效益和社会效益.实船已投入使用。 相似文献