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291.
将现代人工神经网络方法应用于地质学的判别分析,通过实例计算表明,无论是对于两组判别分析还是多组判别分析,人工神经网络方法都是切实可行的。 相似文献
292.
293.
DGPS RTK技术在无验潮水下地形测量中的应用初探 总被引:5,自引:0,他引:5
本文简要介绍了DGPS RTK技术的基本原理和作业流程,阐明了该技术在无验潮水下地形测量中的适用性,并以除六泾水文大断面的测量为例介绍了利用该技术进行工程实测的过程,通过对实测数据成果的分析,得出一些有益的结论。 相似文献
294.
LI Hongwei TAN Jiahua Ph. D. Candidate School of Naval Architecture Ocean Engineering Shanghai Jiaotong University 《中国海洋工程》1998,(4)
This paper analyzes the pipe network system of oil-gas collection and transportation foroffshore oilfield development.A"0-1"integer linear programming model is constructed to optimize theinvestment of seabed pipe network.The mathematical model is solved by the spanning tree method ofgraph theory and network analysis.All spanning trees of a network graph compose all the feasible solu-tions of the mathematical model.The optimal solution of the model is the spanning tree with the minimumcost among all spanning trees.This method can be used to optimize the seabed pipe network system andgive a minimum cost plan for the development of offshore marginal oilfield groups. 相似文献
295.
296.
Xu Shikai Wang Hongchuan Hong Guangwen
Engineer Nanjing Hydraulic Research Institute Nanjing .
Professor Research Institute of Coastal Ocean Engineering Hohai University Nanjing 《中国海洋工程》1996,(4)
To solve problems concerning wave elements and wave propagation, an effective way is the wave energy balance equation, which is widely applied in oceanography and ocean dynamics for its simple computation. The present papaer advances wave energy balance equations considering lateral energy transmission and energy loss as the governing equation for the study of wave refraction-diffraction. For the mathematical model, numerical simulation is made by means of difference method, and the result is verified with two examples. 相似文献
297.
Discussion on Coastal Erosion Near Xizhuang, Penglai, China 总被引:1,自引:0,他引:1
Wu Guiqiu Li Wei Professor First Institute of Oceanography State Oceanic Administration Qingdao Associate Researcher 《中国海洋工程》1994,(2)
-In this work, on the basis of the characteristics of coastal erosion near Xizhuang (Penglai, Shandong, China) and the in-situ measured data and theoretical calculation, the causes of coastal erosion there are obtained: (1) natural erosion, (2) beach sand borrowing, and (3) sand borrowing at the Dengzhou shoal near Xizhuang, which results in the loss of the function of the wave force resistance of the shoal. Since the wave energy is increased, the longshore sediment transport rate is increased. Coastal erosions are more and more serious. A scientific basis to reduced the calamity of coastal erosion in local area is presented. Some experiences are accumulated for studying coastal erosion. 相似文献
298.
Following Bagnold's approach, a relationship between sediment transport and energy dissipation is developed. The major assumption made in the study is that the near bed velocity plays a dominant role in the process of sediment transport. A general relationship between energy dissipation and sediment transport is first proposed. Then the equations for total sediment transport are derived by introducing the appropriate expression of energy dissipation rate under different conditions, such as open channel flows, combination of wave and current, as well as longshore sediment transport. Within the flows investigated, the derived relationships are fairly consistent with the available data over a wide range of conditions. 相似文献
299.
文章采用完全混合活性污泥法研究了大生活用海水进入城市污水系统后 ,不同海水盐度下基质降解与需氧量之间的关系。结果表明随着污水中海水比例的增加 ,代谢单位重量有机物所需的氧量和污泥自身氧化需氧率也呈增加趋势 相似文献
300.
A new kind of nematocyst, heteromorphore, and three new types of nematocysts, microbasic spino-mastigophore, microbasic undulata-mastigophore, microbasic laevis-mastigophore, are described from medusae of the Xiamen Harbour and discussed by comparison with the results of other research workers. 相似文献