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961.
本文利用格网技术(Fishnet),对龙门山地区"5.12"大地震震后的多期次遥感影像数据及基础地理信息数据进行评价、整合并实现了动态管理,在此基础上得到覆盖整个龙门山构造带的、能够反映不同地物信息的影像群.汶川地震造成了大量山体崩塌、滑坡、泥石流等地震场地灾害,这些灾害体表现为成群、成带分布的特征,并且单一的小灾害体... 相似文献
962.
中国南方湿润区红层地貌及相关问题探讨 总被引:5,自引:1,他引:4
我国红层出露面积广大,但地学界对红层关注不足,各学科对红层问题的研究缺乏融合,存在着"多张皮"的问题;尤其是对红层这个特殊的脆弱地理单元的土地退化及生态环境问题缺少关注。南方湿润区是我国红层集中分布区之一,大部分红层区存在着严重的地貌灾害和水土流失问题,甚至分布着许多"红层荒漠"。红层区的土地退化虽与人的不合理利用关系... 相似文献
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965.
Stefano Casotto 《Celestial Mechanics and Dynamical Astronomy》1990,50(2):125-141
The spectra of geopotential, Earth and ocean tidal perturbations on a satellite can be obtained using Kaula's linear theory, or an extension thereof, as summations of terms depending on four indices l, m, p, q. In this work algorithms are presented that generate the equivalence classes induced by the composition rule of frequency on the set of all (l, m, p, q) combinations up to a maximum degree L and maximum value Q of the last index. These algorithms eliminate the need to search the set of frequencies when the linear theory is programmed on a computer. 相似文献
966.
Recombinant eel GH and yeast containing chinook salmon growth hormone (reGHand rcsGH) were incorporated into gelatin and sodium alginate (reGH-GS and rcsGH-GS) or polymer ma-trix (reGH-HP55) to protect the hormone from proteolytic cleavage in the stomach. The diets containin greGH-GS, rcsGH-GS, reGH-HP55 and free-reGH or uncoated-rcsGH were administered to red sea bream. Feeding of reGH-GS, reGH-HP55 and rcsGH-GS diets resulted in significant increases in body weight and fork length over those of controls. These results strongly suggest that gelatin and sodium algi-nate as well as polymer matrix protected the hormone from proteolytic enzymes in the gastrointestinal tract to allow the bioactive hormone to enter the circulation and eventually stimulato fish growth. 相似文献
967.
Josef Hron Walter Nowotny Rita Gautschy-Loidl Susanne Höfner 《Astrophysics and Space Science》2003,286(1-2):213-218
We present synthetic radii and visibilities in the IR, based on hydrostatic and dynamic model atmospheres of carbon stars.
The differences between these two sets of input models and to uniform disc models are discussed and compared to the expected
capabilities of the VLTI.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
968.
《The Professional geographer》1987,39(2):238-266
Book Reviewed in this article: Women, Work, and Ideology in the Third World . Haleh Afshar, ed. The Birth of the National Park Service. The Founding Years 1913–33 . Horace M. Albright Theatres of Accumulation: Studies in Asian and Latin American Urbanization . Warwick Armstrong and T.G. McGee. New Tools for Social Scientists, Advances and Applications in Research Methods . William D. Berry and Michael S. Lewis -Beck , eds . Uncertain Dimensions: Western Overseas Empires in the Twentieth Century . Raymond F. Betts. Geography of Sugar Cane . Helmut Blume. The Mines of Neptune: Minerals and Metals from the Sea . Elisabeth Mann Borgese. Geographical Dimensions of Energy . F.J. Calzonetti and B.D. Solomon, eds. Statistical Methods for Geographers . W. A. V. Clark and P. L. Hosking. In The Wake of Columbus, Islands and Controversy . John DeVorsey, Jr., and John Parker, eds. Housing, States and Localities . Peter Dickens, Simon Duncan, Mark Goodwin and Fred Gray. Physician Location and Specialty Choice . Richard L. Ernst and Donald E. Yett. Practical Ecology for Geography and Biology: Survey, Mapping, and Data Analysis . D.D. Gilbertson , M. Kent and F.B. Pyatt Large Scale Water Transfers: Emerging Environmental and Social Experiences . Genady N. Golubev and Asit K. Biswas, eds. The Nature of the Environment . Andrew Goudie. Planning for Population Change . W.T.S. Gould and R. Lawton. The Niger and its Neighbors: Environmental History and Hydrobiology. Human Use and Health Hazards of the Major West African Rivers . A.T. Grove, ed. Remote Sensing of Ice and Snow . Dorothy K. Hall and Jaroslav Martinec. Atlas of Antebellum Southern Agriculture . Sam Bowers Hilliard. Galilee Divided; The Israel-Lebanon Frontier, 1916-1984 . Frederic C. Hor . Plains Country Towns . John C. Hudson. Agricultural Geography: A Social and Economic Analysis . Brian W. Ilbery. Industry in the 1980s: Structural Change and Interdependence . U.N. Industrial Development Organization. Crabgrass Frontier: The Suburbanization of the United States . Kenneth T. Jackson. The Industrial Geography of Italy . Russell King. Studies in Linguistic Geography: The Dialects of English in Britain and Ireland . John M. Kirk, Stewart Sanderson, J.D.A. Widdowson, eds. Tourism: A Community Approach . Peter E. Murphy. Cities and Services: The Geography of Collective Consumption . Steven Pinch. An Historical Geography of Europe 1800–1914 . Norman J. G. Pounds. An Introduction to Human Ecology Research on Agricultural Systems in Southeast Asia . A. Terry Rambo and Percy E. Sajise, eds. Discovering Past Landscapes . Michael Reed, ed. Managing the Ocean: Resources, Research, Law . Jacques G. Richardson, ed. Carta fitosociologica de la transecta botanica de la Patagonia Austral . F.A. Roig , Juan Anchorema , Orlando Dollenz , A.M. Faggi and Eduardo Mandez Intermetropolitan Migration in Canada: Changing Determinants over Three Decades . R. Paul Shaw. Chinese Cities—The Growth of the Metropolis since 1949 . Victor F. Sit, ed. Urbanization in the World-Economy . Michael Timberlake, ed. The Al Business: Commercial Uses of Artificial Intelligence . Patrick H. Winston and Karen A. Prendergast, eds. 相似文献
969.
ImODUcnONThemacronutrientShitrogen,phosphorus,andsiliconhaveoftenboconsidedtodritthegroWthrateofmarinephytoplankton.RamtstudAsreveatalthattraeernetalAncronutrientSmaybeofsignilicanceintheerelogyofphytoplankton(RueterandUnsworth,l99l,Brandetal.,1983,HatheonandMore,l986).IronisacomPonentofmanyalgaeproteinsparticularlytwortantforbiosynthesisofchiorophyllandeleCtrntIansportrmCtionsofrespthetionandphotosynthesis,andisCrUdalfornitrogenmetaboljsmdriusehemeandiron-stilfUrcomPoundsarethecofact… 相似文献
970.
The primary objective of this study is to investigate the possibility of including more temporal and spatial information on short‐term inflow forecasting, which is not easily attained in the traditional time‐series models or conceptual hydrological models. In order to achieve this objective, an artificial neural network (ANN) model for short‐term inflow forecasting is developed and several issues associated with the use of an ANN model are examined in this study. The formulated ANN model is used to forecast 1‐ to 7‐h ahead inflows into a hydropower reservoir. The root‐mean‐squared error (RMSE), the Nash–Sutcliffe coefficient (NSC), the A information criterion (AIC), B information criterion (BIC) of the 1‐ to 7‐h ahead forecasts, and the cross‐correlation coefficient between the forecast and observed inflows are estimated. Model performance is analysed and some quantitative analysis is presented. The results obtained are satisfactory. Perceived strengths of the ANN model are the capability for representing complex and non‐linear relationships as well as being able to include more information in the model easily. Although the results obtained may not be universal, they are expected to reveal some possible problems in ANN models and provide some helpful insights in the development and application of ANN models in the field of hydrology and water resources. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献