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91.
Shaohua Marko HSU Associate Professor Dr. Department of Hydraulic Engineering Feng Chia University Taichung Taiwan China Wei-Sheng YU Environment Section Agricultural Engineering Research Center Chungli Taiwan China Tzu-Ming LIU Graduate stu 《国际泥沙研究》1997,(3)
1.IN~DUCTIONTurbiditycurrentisoneclassofflowsnameddensitycurrentorgravitycurrent(therHunterRouse(Yih(1980)),whichdePictstheintmsionofheaVyfluidintoalighterone.Usually,thedensitydifferencebetWeentWonuidisrelativelysmallandmixingacrosstheimerfaceoccurs.ThedrivingforceofdensitycurrentsisnotdensitydifferenceitselfbutthedifferenceinspeCmcweights.Turbiditycurrentisnamedwhenthedensitydifferenceisespeciallycausedbysuspendedfinesedimentparticles.Sincesediment-ladenflowcaninteraCtwiththelowerbou… 相似文献
92.
Vicente L. LOPES Assistant Professor School of Renewable Natural Resources The University of Arizona Tucson Arizona Peter F. FFOLLIOTT Professor School of Renewable Natural Resources The University of Arizona 《国际泥沙研究》1992,(3)
A conceptual modeling framework for developing process-based mathematical models of sediment generation, transport, and deposition on broad shallow flow areas is presented. The governing equations relevant to process-based modeling of broad shallow flow sediment processes on small watersheds are presented and the effects of space and time averaging on the predictive equations are described. Starting from the most general one-dimensional, unsteady model of sediment processes, simpler model structures are obtained and the successive simplifications made on the governing equations in order to obtain simpler and less detailed formulations are described. Specific model formulations are given for illustrative purposes and applications of these models to erosion and sediment yield prediction from broad shallow flow areas are shown using sediment data from rainfall simulator plots. In spite of some progress made in the development of process-based erosion and sediment yield models from broad shallow flow areas, further developmental modeling efforts must be based on a clear separation between hydrologic and hydraulic processes, and the soil properties which are significant for each. 相似文献
93.
M. de Vries G. J. Klaassen N. Struiksma Professor Delft University of Technology. The Netherlands. Delft Hydraulics. The Netherlands. 《国际泥沙研究》1990,(1)
I. INTRODUCTIONMore than a decade ago, under tile auspices of DELFT HYDRAULICS an overview on the use ofmodels for river problems was given (de Vries & van der Zwaard. 1975). Since then a better understanding of morphological processes in rivers has been obtained, their mathematical formulation hasbeen improved and computer facilities have been expended. Scale models and mathematical models arein use. but their field of application is gradually changing. It seems that the better ma… 相似文献
94.
Pu Wang R. Kahawita Professor of Mechanics Lenzhou University Lanzhou China. Professor of Civil Ensineering Ecole Polytechnique de Montreal Canada. 《国际泥沙研究》1990,(1)
I. INTRODUCTIONNumerical models of estuaries incorporating simulation of the density induced circulation are consideredimPOrtant tools in the assessment of their dispersive characteristics. Most models to date have used finite difference approximations to the governing equations (see for example thericke and Hogan, 1977, Blumberg,1 977, Perrels and Karelse, 1978). A numeriCal model of estuarine circulation using a SADI (Spline Alternating Direction implicit) procedure together with a… 相似文献
95.
96.
Professor Dr. Kurt Spangenberg Z. Heidenheim 《Contributions to Mineralogy and Petrology》1949,1(5-6):529-535
Ohne ZusammenfassungAbgeschlossen iiim Juni 1947. 相似文献
97.
Professor Dr. Kurt Spangenberg Dr. Martha Müller Z. Heidenheim 《Contributions to Mineralogy and Petrology》1949,1(5-6):547-559
Ohne ZusammenfassungAbgeschlossen im Juni 1947. 相似文献
98.
Professor Walther Penck 《International Journal of Earth Sciences》1924,14(3):301-315
Ohne Zusammenfassung 相似文献
99.
本篇分为三节:第一节论研究(竹廷)蜗之方法及其各部分之名称;并猎取古生物学家迄今历史之结果而加以批评。第二节专述中国北部已发见之(竹廷)蜗。第三节讨论本篇所述各种(竹廷)蜗生存之时代及其棲息流徙之情形。 相似文献
100.
Changsintien is a station on the Peiping-Hankow railway and is situatedabout 20 km S.W.of Peiping.Further S.W.for about 15 km is the townof Tuoli where begins the Tuotsin aerial ropeway for transporting coal and at 相似文献