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101.
MEI Hualin WU Changhua Tianjin Institute of Geology Mineral Resources CAGS Tianjin. JIN Wei Changchun University of Earth Sciences Changchun Jilin Hao Zhiguo Liu Xinzhu 《《地质学报》英文版》1998,72(1):14-28
Four distinct lithe-tectonic belts (zones) in the Yinshan area, North China, were identified by pressure-temperature contours and litho-tectonic features, such as the Sanggan granulite belt, Jining metasedimentary belt. Wulashan-Daqingshan front tectonic zone and Se' eratengshan belt. This area witnessed two important thermo-tectonic events. The older one is c. 2.5 Ga while the younger one c. 1.9 Ga. The Se' ertengshan Neoarchaean terrane features a clockwise PT path with the decompression ranging from > 1500 MPa to 800-1000 MPa in the Se' ertengshan belt, which implies an island arc setting. The Sanggan belt is a Mesoarchaean microcontinent reworked by Neoarchaean magma underplating, which shows an counterclockwise PT path. During the Palaeoproterozoic period, two Archaean continent (arc) collided. The Archaean basement of the Sanggan and Wulashan-Daqingshan belts overthrust northwards, the PTt paths of basement show a decompression from 1000-1200 MPa to 500-700 MPa. The PT paths of the Jining and Erda 相似文献
102.
This paper presents the detail design conditions, design criteria and methods as well as design conclusions of the process, structure and corrosion of the production flowlines and high pressure water injection lines in BZ34-2 / 4 oil field in Bohai Bay. At present this design represents the design capability and level in the field of the submarine pipeline engineering of China. 相似文献
103.
TANG Wenyong ZHANG Shengkun CHEN Tieyun Doctor School of Naval Architecture Ocean Engineering Shanghai Jiaotong University 《中国海洋工程》1998,(3)
This paper analyzes the dynamic structure-fluid interaction response of a submerged compo-site cylindrical shell.Dynamic equations based on the first-order shear deformation theory include the ini-tial stresses and structure-fluid interaction forces due to fluid.The field equation is solved by expandingthe velocity potential into series similar to transverse deflection of the cylindrical shell and thestructure-fluid interaction force is obtained.The dynamic response is investigated by means of series expan-sion method.The effects of structure-fluid interaction on dynamic response are discussed. 相似文献
104.
Yan Shuwang Yang Jinliang Yan Chi Professor Tianjin University Tianjin
Assoc. Professor Tianjin University Tianjin
Lecturer Tianjin University Tianjin 《中国海洋工程》1992,(4)
The results of undrained cyclic triaxial tests on three types of clays are collected and a relationship among the accumulated strain, the initial stress state, cyclic stress in the soil, as well as the number of cycles is established based on the experimental data. With this relationship, a procedure is proposed for subsidence and stability analysis on soft clay under the action of cyclic loads. 相似文献
105.
BP网络学习参数模糊自适应算法的实现 总被引:1,自引:2,他引:1
前馈神经网络BP算法的改进方案中,对网络训练(学习)过程中学习率和惯性系数进行模糊自适应调节,以提高收敛速度,是一项很有效的措施。文中具体分析了如何根据设计者的先验知识确定模糊规则和隶属函数,并以三比特异或函数(或称奇偶分类)的实现为例,验证了这种算法的改进、加速了BP网络的学习过程。 相似文献
106.
Shi Qingzeng Chen Xing
Professor Dept. of Ocean Eng. Naval Arch Tianjin Univ. Tianjin
Lecturer Dept. of Ocean Eng. Naval Arch. Tianjin Univ. Tianjin 《中国海洋工程》1995,(2)
Spectrum and self-excite characters are the two significant characters of the dynamics of sea ice. The spectrum character of sea ice is mainly shown by the spectrum of ice force. The spectrum character of the sea ice is its intrinsic attributes. When the spectrum of ice force from the dynamic response of ice and structure interaction are evaluated, the effect of dynamic character of the structure must be eliminated. In this paper, the ice force spectrum at Bohai Bay and Liaodong Bay is evaluated from the displacement and strain responses of a single degree and a multi-degree freedom structure. The evaluated ice force spectrum can be used to define the spectrum character of ice in the analysis of ice induced vibration. 相似文献
107.
Asymptotic Analysis Methods for Structural Reliability 总被引:2,自引:0,他引:2
Zhao Guofan Li Yungui Wang Hengdong
Professor Dept. of Civil Engineering Dalian University of Technology Dalian Ph. Doctor China Academy of Building Research Beijing Ph. Doctor Dept. of Civil Engineering Dalian University of Technology Dalian 《中国海洋工程》1995,(3)
- Applying Laplace asymptotic approximation of integral, asymptotic analysis methods of structural reliability are proposed in generalized and orthogonal random space. Analytic results show that the proposed methods are simple in calculation and accurate enough for problems of continuous random variables. 相似文献
108.
Chu Liangcheng Qu Naisi Guo Yonggang Lu Min Ph.D. Dalian University of Technology Dalian
Associate Professor Dalian University of Technology Dalian
Assistant M.S. Dalian University of Technology Dalian
Engineer Bohai Oil Company Tianjin 《中国海洋工程》1993,(4)
- Theoretically speaking, it is impossible to make the differential equation of motion uncoupled for the natural modes of a system in consideration of the attached water. The hydro-elastic structure is equal to the, non-proportional damping system. In this paper a perturbation analysis method is put forward. The structure motion equation is strictly solved mathematically, and the non-proportional damping problem is transformed into a series of proportional damping ones in the superposition form. The paper also presents the calculation formula of the dyanamic response of the structure being subjected to harmonic and arbitrary load. The convergence of the proposed method is also studied in this paper, and the corresponding convergence conditions are given. Finally, the proposed method is used to analyze the displacement response of a real offshore platform. The calculation results show that this method has the characteristics of high accuracy and fast convergence. 相似文献
109.
Stress Analysis of Spatial Non-Concurrent Tubular Joints 总被引:1,自引:0,他引:1
ChenTieyun Wu Zhengqi
Professor Shanghai Jiaotong University Shanghai
P. h. Doctor Shanghai Jiaotong University Shanghai 《中国海洋工程》1994,(4)
The formulations of analytic-numerical method for the stress analysis of non-concurrent spatial tubular joints are introduced in the paper. The spatial DT joints with different eccentricity in the vertical diametrical plane of chord are computed. Finally the influence of eccentricity on the stress at possible hot spots is discussed. 相似文献
110.
Yan Chi Zhang Jianguo Yan Shuwang
Lecturer Dept. of Hydraulic Eng. Tianjing University Tianjin
Professor Dept. of Hydraulic Eng. Tianjing University Tianjin 《中国海洋工程》1994,(4)
- Based on the theory of limit analysis, the Finite Difference Method (FDM) is established for evaluating the ultimate bearing capacity of subsoils to bear the unburied pipelines. The analytical results of bearing capacity of the ideal clay is given. The approach to bearing capacity evaluation of cohesionless subsoils without surcharge is suggested. The results from this method are consistent with those obtained from model tests. 相似文献