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排序方式: 共有438条查询结果,搜索用时 15 毫秒
51.
XU Jiongxin Professor Institute of Geography Chinese Academy of Sciences Beijing China 《国际泥沙研究》1997,(3)
LINTRODUCTIONThetributariesofmiddleYellowRiverarefamousintheworldforthehighestsuspendedsedimentconcentrationandsedimentyield.Forexample,atWenjiachuanstationofKuyeheRiverthemeasuredhighestsuspendedconcentrationis1700kg/m',andthemeanannualsedimentyieldis25000t/(kln'.a).Theformationofhyperconcentratedflowsandtheirinfluenceonerosionprocessesareofgreatimportancenotonlyfromatheoreticalpointofviewbutalsoforpracticalpurposes.Therefore,scientistsfromChinaandallovertheworldhavedrawntheirintensio… 相似文献
52.
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
53.
Dr. K. -H. Nitsch Professor Dr. H. G. F. Winkler 《Contributions to Mineralogy and Petrology》1965,11(5):470-486
The equilibrium curves for the reactions:
- (a)4 orthozoisite + 1 quartz ? 5 anorthite + 1 grossularite + 2 H2O. 相似文献
54.
Nicholas Dodd 《中国海洋工程》1995,(2)
A nonlinear short-wave-averaged (surf beat) model is presented. The model is based on that of Roelvink (1993), but the numerical techniques used in the solution are based on the so-called weighted-averaged flux (WAF) method (eg Watson et al., 1992), with time-operator splitting used for the treatment of some of the source terms. This method allows a small number of computational points to be used, and is particularly efficient in modelling breaking long waves. The short-wave (or primary-wave) energy equation is solved using a more traditional Lax-Wendroff technique. Results of validation indicate that the model performs satisfactorily in most respects. 相似文献
55.
Li Yucheng He Ming Professor Dalian University of Technology Dalian Former master student Dalian University of Technology Dalian 《中国海洋工程》1994,(3)
-Based on the extended Morison Equation and model tests, the in-line forces on small square cylinders caused by waves (regular and irregular) and currents are analyzed in detail in this paper. The hydrodynamic coefficient CD and Cu related to KC number and the effect of direction of wave incidence are also given, which can be used in engineering practice. 相似文献
56.
Lian Gan Ni Kan Hu Kai Guo Dawei . Professor Senior Engineer Marine Design & Research Institute of China Shanghai
. Senior Engineer Marine Design & REsearch Institute of China Shanghai
. Engineer Marine Design & Research Institute of China Shanghai 《中国海洋工程》1992,(4)
This paper describes the study of a single-column structure used as well-head platform. In order to check the reliability of computation theory and programme, model tests have been carried out. The paper introduces the conclusion of tests and the dynamic properties of single-column platform are obtained. 相似文献
57.
WANG Guixian WANG Xingkui GUO Jiachao Professor Sediment Research Laboratory Dept. of Hydraulic Engineering Tsinghua University Beijing China. Associate Professor Dept. of Hydraulic Engineering Tsinghua University. Assistant Dept. of Hydraulic Engineering Tsinghua University. 《国际泥沙研究》1993,(3)
I. INTRODUCTIONResistance to flow in alluvial streams is one of the crucial problems in fluvial hydraulics. Despite that large amount of studies have been conducted for centuries, no perfectmethod describing and calculating the resistance to flow in alluvial streams is availablehll now. Investigation on bed forms and resistance properties of light--weight bed materials is even more scarce. USWES (1936) has conducted systematic experiments onlight--weight materials in a flume & m long an… 相似文献
58.
The Optimal Design of TMD for Offshore Structures 总被引:15,自引:0,他引:15
This paper presents the optimal design procedure of Tuned Mass Damper(TMD)for re-ducing vibration of an actual steel jacket offshore platform excited by random wave loading.In this study,a frequency domain is taken.The force on the structure is determined by use of the linearized Morisonequation for an input Power Spectral Density(PSD)of wave elevation.The sensitivity of optimum valuesof TMD to characteristic parameters of random wave spectrum is analyzed.An optimized TMD designfor the modeled platform is given based on design conditions and the findings of the study. 相似文献
59.
Zhang Jianguo Yan Chi Yan Shuwang
Lecturer Dept. of Hydraulic Eng. Tianjin University Tianjin Associate Professor Dept. of Hydraulic Eng. Tianjin University Tianjin Professor Dept. of Hydraulic Eng. Tianjin University Tianjin 《中国海洋工程》1996,(1)
This paper describes the model tests for determining the axial friction and the lateral resistance of sand to pipeline by using fine sand and prototype pipeline, and the calculation method based on limit analysis theory is verified. The effect of cyclic loading is considered in the test. 相似文献
60.
In the test-field calibration,multi-azimuth stereo image pairs areproduced of the outdoor large control-field by the stereo-vision system under cali-bration.While in the analytical processing,the relationship between image pairsis adopted as a constraint condition,which ensures the stability and quality of thecalibration results.This paper introduces the deduction process of the constraintconditions. 相似文献