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根据冲量相似的要求进行船舶在冲击作用下的模型试验,并将模型试验结果与理论计算及实际试验进行了对比和分析。 相似文献
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1 .IntroductionAshiptravelingatseaundergoesundesirablewave inducedmotions ,namely ,surge ,sway ,heav ing ,rolling ,pitchingandyaw .Thesemotionsoftencauseproblemstothecrew ,theonboardequip mentand ,intheworstcase ,thesafetyofthevessel.Tominimizethewave inducedshipmotions ,controlsystemsmaybeapplied .Theaccuratemodelingofshipmotionsisthereforeveryimportantforshipdesignanddesignofmotioncontrolsystems .Manyresearchershavedevelopedshipmotionpredictionmethodsbasedonthepotentialflowtheo ries (Dong ,… 相似文献
4.
K. G. Robertson 《Marine Geophysical Researches》1990,12(1-2):3-8
Accurate navigation forms an essential part of all research at sea and the deep ocean imposes it's own unique problems. This chapter discusses several of the techniques in current use on the research vessels of the Natural Environment Research Council (NERC), concentrating on those systems which provide global navigation facilities, as opposed to the more localised, coastal aids. Whilst most of the systems rely on surface propagation of radio waves, the use of acoustics and sea-bed mapping instruments constitute accurate alternatives for some sub-sea applications. 相似文献
5.
Zhang Furan Zhao Jun Zhang Xueqin Assistant Researcher Tianjin Research Institute of Water Transport Engineering Tianjin Assistant Engineer Tianjin Research Institute of Water Transport Engineering Tianjin 《中国海洋工程》1993,(2)
In respect of an offshore berthing pillar, the test study result of current force acting on mooring ships is described in this paper. Empirical and semi-empirical relationships of current force coefficient are given according to the angle between the flow direction and the ship's longitudinal axis, which are coincident with the result of theoretical analysis. 相似文献
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This chapter describes two separate but complementary research echosounder systems originally developed by Krupp Atlas Elektronik GmbH for the new German oceanographic research vessel Meteor.The Hydrosweep is a Hydrographic wide-swathe sweep survey echosounder for both shallow and deep water applications providing accurate bathymetric surveys and terrain-following navigation capabilities.The Parasound system is a hull-mounted dual channel parametric narrow-beam deep sea survey and sub-bottom profiling echosounder enabling particularly high vertical and horizontal resolution of seabed features. 相似文献
8.
Tan Jiahua Ma Wei Pan Bin Associate Professor Shanghai Jiao Tong University Shanghai Lecturer shanghai Jiao Tong University Shanghai 《中国海洋工程》1992,(1)
The basis, process and results of the demonstration of the main dimensions of a 75000t floating production and storage vessel are discussed in this paper. A simple but reliable orthogonal design method is applied in the main dimension optimization. The ideas of gradual approximation and feedback from various aspects are put into effect. During the demonstration, in order to make the model tally with the actual situation, the draft design is closely related to the computational analysis, so that the demonstration model can be verified at any time; the handling of the overall system is closely related to the research of each item, which is beneficial not only to the mastery of various regularities, but also to the balance of decisions. Finally, according to the computational results and the regularities obtained from analysis, the main dimensions are determined. 相似文献
9.
Tang Rongqing Wang Daoyan Zhang Xixian Egnineer Shanghai Jiao Tong University Shanghai Associate Professor Shanghai Jiao University Shanghai 《中国海洋工程》1993,(3)
- The authors have used a low-cost ROV of observation type for underice surveying of the Nen-Jiang Cross-river oil pipe line in the Da Qing oil field. The operation method, process and the safety measures for severe cold areas are presented. The fruitful tries and experience may be useful to ROV operators in severe cold areas. 相似文献
10.
Q. Huggett 《Marine Geophysical Researches》1990,12(1-2):69-81
Although the optical properties of seawater at extreme depths are more suitable for underwater photography than those at the surface or on continental shelves, they still impose severe limitations on long-range wide area bottom photography. Additionally, deep ocean operations impose technical limitations on control, power and bandwidth. This chapter reviews the approaches contemplated or made towards improving the camerato-target range in underwater photography in the deep ocean. Further significant improvements await advances in control, power/light sources and bandwidth reduction. With the developments now contemplated, TV and video systems will eventually present a strong challenge to emulsion film techniques. 相似文献