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41.
Weng Keqin
Associate Professor Hydraulic Hydro-Power Engineering Dept. Tsinghua University Beijing 《中国海洋工程》1995,(2)
This paper reveals that the long-period statistic distribution of the characteristic heights of deep-water waves assumes the lognormal distribution. Thereafter, the largest wave-height which may occur in the service life of coastal structures is derived in this paper. 相似文献
42.
Qiu Dahong Zang Jun Jia Ying
Academician of the Chinese Academy of Sciences Professor the State Key Laboratory of Coastal Offshore Engineering 《中国海洋工程》1996,(2)
Based on the 2nd order cnoidal wave theory, the characters of shallow water standing waves and their action on vertical walls are studied in this paper. The theoretical expressions of the wave surface elevation in front of and the wave pressure on the vertical wall are obtained. In order to verify the theoretical results, model tests were made in the State Key Laboratory of Coastal and Offshore Engineering at DUT. For the wave surface elevation in front of the wall and the wave forces on the wall at the moment when the wave surface at the wall surface goes down to the bottom of the wave trough, the calculated results coincide quite well with the experimental results. For the wave forces on the wall at the moment when the wave surface at the wall surface goes up to the top of the wave crest, the theoretical expressions are modified by the experimental results. For the convenience of practical use, calculations are made for the wave conditions which usually occur in enginering practice by use of the inves 相似文献
43.
44.
Gao Yinli Yan Shuwang Wang Jinying
Graduate Student Tianjin University Tianjin
Professor Tianjin University Tianjin
Senior Engineer China Offshore Oil Engineering Co. 《中国海洋工程》1995,(1)
This paper introduces a stability design system of submarine pipelines. The system can provide a reasonable design procedure for users with reference to domestic and foreign methods and in the light of home engineering experience. 相似文献
45.
46.
Cao Guoao Shen Yilei
Dr.Professor Tongji University Shanghai
Shanghai College of Architectural Municipal Engineering Shanghai 《中国海洋工程》1991,(1)
In this paper, the responses of the interaction system of R.C. gravity single-leg platform to seismic excitation are mainly analysed. A set of nonlinear equations for the interaction system are established by using the wave, one is the soil-structure interaction and the other is the fluid-structure interaction. The seismic response of the interaction system is analysed for the influence of the asymmetric structure, fluid action, etc. with the input of seismic SH waves in any direction. The numerical results are given for a simple example. 相似文献
47.
黄河三角洲沿岸及邻近海区细粒沉积物中的碳酸盐 总被引:4,自引:0,他引:4
本文用X-射线衍射法直接计算了来自黄河三角洲沿岸及邻近海区80个沉积样的细粒组分(<2μm)中的碳酸盐含量。计算结果与全样的容量法分析结果基本一致。研究结果表明,本区细粒沉积物中碳酸盐含量变化受沉积物来源、海区水动力作用、海底地貌特征和碳酸盐的地球化学行为等因素所影响。 相似文献
48.
培育双壳类软体动物幼苗所需的饵料,是指池内培育阶段适合于幼虫和幼苗(壳长一般在1mm以下)的饵料。育苗成功的关键问题之一为是否已经选择到这样的饵料。自40年代找到适宜的饵料生物以后,双壳类幼虫的培养才取得较明显的成效。以往利用过的一些饵料生物巳有文献系统记载。我国贻贝人工育苗是在分离与培养出扁藻以后才获得成功的。随着研究工作的深入以及适应各种不同情况的需要,采用的饵料种类越来越多样化。从生产性育苗特别是多茬育苗考虑,必须因地制宜地筛选出一定种数的饵料,以便在不同培养条件下有机动选择的余地。同一时还应找出适宜的投饵数量,以求取得较好的育苗效果。为此目的,我们于1975-1978年结合生产性育苗的需要进行了一些饵料饲养实验。本文根据实验结果以及多年来生产性育苗的实践,对贻贝育苗的饵料问题进行总结,侧重于不同饵料的饲养效果比较。 相似文献
49.
Study of zooplankton ecology in Zhejiang coastal upwelling system-Zooplankton biomass and abundance of major groups 总被引:1,自引:0,他引:1
He Dehu Yang Guanming Fang Shaojin Shen Weilin Liu Hongbin Gao Aigen Huang Shuxin 《海洋学报(英文版)》1988,7(4):607-620
The studied area is a shallow water area that belongs to the East China Sea continent shelf. The distribution of zooplankton biomass is higher inshore than offshore. The maximum abundance is in the inshore edge of the centre of upwelling, which is the superposed area of the salinity front and temperature front, due to the fact that the mixture of three different waters has brought about a concentration of nutrients. The herbivorous Euphausia, Copepoda and Tunicata are the major groups of the abundant area. Tunicata possess the possibility to compete against other kinds of herbivorous zooplankton. This means that there is negative correlation between the distribution of Tunicata and that of Copepoda and Euphausia. The positions of maximum areas of zooplankton biomass, phytoplankton individual and the concentration of phosphates and chlorophyll-a overlap one another. In the centre of upwelling, zooplankton can not adapt itself to the environment of lower temperature and less oxygen even with rich nutrient 相似文献
50.
Li Yucheng Wang Fenglong Professor Dalian University of Technology Dalian Senior Engineer Dalian University of Technology Dalian 《中国海洋工程》1993,(1)
- The wave-current forces on vertical piles in side-by-side arrangement induced by irregular waves with opposing current are investigated experimentally in this paper. The characteristics in both time and frequency domain of in-line, lift and resultant forces are analyzed. The grouping effect coefficients of inline, lift and resultant forces on piles related to KC number and relative spacing parameters are given. These results are compared with those in the case of irregular waves combined with following currents. It is found that the results in these two cases are quite different. The range of KC number tested is 10- 60, the range of Reynolds number is (0.55-3.43) ×104. 相似文献