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NUMERICAL EXPERIMENT OF THE INFLUENCES OF HEAT AND WIND STRESS ON THE EQUATORIAL OCEAN CIRCULATION 总被引:1,自引:0,他引:1
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A time-dependent linear model on the equatorial beta plane is developed in this paper.Its verticalstructure consists of two active layers with equal density and temperature above the thermocline and aquasi-stationary layer with constant density below the thermocline.The results of nurnericat experiments show that the direct influence of heat on the equatorial ocean ismuch smaller than that of wind stress.Nevertheless,through the tropical ocean-atmosphere interaction,the change of wind stress resulting from the thermal forcing may set a determinant effect on the equilibriumand anomalous development of the ocean-almosphere circulation. 相似文献
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GPS定位技术在高层建筑施工基准传递中的应用 总被引:4,自引:0,他引:4
在高层建筑施工中,基准传递是一项极为重要的测量工作,为了满足现代建筑工程快速、高效、优质的施工需要,文中提出应用GPS定位技术实施施工基准定位的方法,并结合工程实测就作业过程作了阐述。结果表明,在超高层建筑的基准传递中,应用GPS是一种行之有效的新方法。 相似文献
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赤峰西部地区金矿床成矿时代及其成矿机制的新认识 总被引:18,自引:0,他引:18
赤峰西部地区产华北板块与兴蒙造山带拼合部位南侧的板块北部边缘带上,为著名的赤峰-朝阳金矿集中区重要金矿产地之一。本区金矿床包括两种类型:柴胡栏子金矿床为蚀变岩型金矿床为蚀变岩型金矿;莲花山和红花沟金矿床属石英脉型。诸多地质事实表明这些矿床的形成均与中基性岩浆活动密切相关。野外观察和同位素年代学资料说明中基性岩浆活动发生在印支期。因此,笔者提出本区金矿成矿时代为印支期的新认识,否定了以往一些研究者提出本区金成矿作用是发生在燕山期或海西期的看法。同时,在综合分析基础上,提出本区金矿床是在印支期构造-岩浆活动作用下、区域隆起的过程中形成的产物,从而对本区金矿床的形成机制做出了新的解释。 相似文献
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Time is a crucial factor for many remote sensing applications such as emergency response. The traditional approach requires users to spend a lot of time downloading, processing, and viewing satellite images with specialized software. Realizing interactive real‐time processing and visualization of satellite images online is our focus. This article presents an On‐Demand computing schema for remote sensing images. A processing chain model is proposed for satellite images on a private cloud computing platform designed for the China Centre for Resources Satellite Data and Application (CCRSDA). The architecture, processing flow, optimization method, fault tolerance, and user interface are described in detail. To test the efficiency and scalability of the platform, 11 processing chains were created and three load balance experiments were executed. The results from these experiments show the validity of the proposed methods and architecture. 相似文献
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本文首先推导出单位失变率的矢量表示式.然后将该式应用于惯性系运动学问题,以球坐标系为例导出了曲线坐标系中速度、加速度的分量表示式,导出了自然轴系中切向加速度和法向加速度的表示式.最后将该式应用于非惯性系运动学问题,在导出绝对变本与相对变率关系的基础上,进而得出绝对运动与相对运动的关系.显示出此种方法在研究运动学问题时的优越性. 相似文献
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MA Changqian SHE Zhenbing XU Pin & WANG Lingyan State Key Laboratory of Geological Processes Mineral Resources and Faculty of Earth Sciences China University of Geosciences Wuhan China 《中国科学D辑(英文版)》2005,48(8):1134-1145
The Dabieshan Orogenic belt is well known for the exhumation of early Mesozoic ultrahigh-pressure (UHP) metamorphic rocks and Jurassic–Cretaceous emplacement of voluminous granitoids. However, the tectonic evolution in the orogen during the Paleozoic, especially its magmatic response to tectonism has not received much attention. As indicated by published data, the Dabieshan orogenic belt contains different records of Paleozoic magmatic-tectonic association in different tectonic units. Occ… 相似文献
20.
Based on the daily precipitation data of 27 meteorological stations from 1960 to 2009 in the Huaihe River Basin, spatio-temporal trend and statistical distribution of extreme precipitation events in this area are analyzed. Annual maximum series (AM) and peak over threshold series (POT) are selected to simulate the probability distribution of extreme precipitation. The results show that positive trend of annual maximum precipitation is detected at most of used stations, only a small number of stations are found to depict a negative trend during the past five decades, and none of the positive or negative trend is significant. The maximum precipitation event almost occurred in the flooding period during the 1960s and 1970s. By the L-moments method, the parameters of three extreme distributions, i.e., Generalized extreme value distribution (GEV), Generalized Pareto distribution (GP) and Gamma distribution are estimated. From the results of goodness of fit test and Kolmogorov-Smirnov (K-S) test, AM series can be better fitted by GEV model and POT series can be better fitted by GP model. By the comparison of the precipitation amounts under different return levels, it can be found that the values obtained from POT series are a little larger than the values from AM series, and they can better simulate the observed values in the Huaihe River Basin. 相似文献