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41.
采用广义点摄影测量理论对建筑物立面框架轮廓进行重构。广义点是对当代线摄影测量以及无穷远点(灭点)理论的升华。实验结果表明,采用线面基元进行立面重构相比于经典的点云重构方法,不仅简洁、高效,还能获得清晰的三维边缘轮廓,且自动化程度较高。  相似文献   
42.
This study aims to examine the effect of El Nino and La Nina on the monthly and seasonal climate of Hong Kong against the ENSO-neutral situation from a statistical perspective. Monthly and seasonal temperature and rainfall of Hong Kong and monthly number of tropical cyclones (TCs) coming within 500 km of the city over the 59-yr (1950-2008) period are examined under three ENSO situations, namely El Nino, La Nina, and ENSO-neutral. It is found that, compared with the ENSO-neutral situation, El Nino tends...  相似文献   
43.
The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangxi, Guangdong and Fujian provinces, with a total area of about 550,000 km2. This metallogenic province is well known in the world for its rich tungsten and tin resources. In the past 40-odd years, a vast amount of mineral exploration activities and studies of the geology of mineral deposits have been carried out and great achievements obtained in the province. This paper is focused on a discussion about the deep tectonic processes in the orogenic belt during the Mesozoic and their contribution to the superaccumulation of metals. Tectonically, this metallogenic province is composed of three units: (1) the marginal continental orogenic belt in the Southeastern Coast fold system in the Yanshanian; (2) the intercontinental orogenic belt in the collision suture belt between the Yangtze and Cathay  相似文献   
44.
In the gneisses from the drillhole ZK2304 of the Donghai area, there have been preserved high- and ultrahigh-pressure metamorphic mineral assemblages, a series of complicated retrogressive textures and relevant metamorphic reactions. In addition to garnet, jadeititic-clinopyroxene and rutile, other peak stage (M2) minerals in some gneisses include phengite, aragonite and coesite or quartz pseudomorphs after coesite. The typical peak-stage mineral assemblages in gneisses are characterized by garnet + jadeitic-clinopyroxene + rutile + coesite, garnet + jadeitic-clinopyroxene + phengite + rutile ± coesite and garnet + jadeitic-clinopyroxene + aragonite + rutile ± coesite. The grossular content (Gro) in garnet is high and may reach 50. 1 mol%. The SiO2 content of phengite ranges from 54.37% to 54.84% with 3.54-3.57 p.f.u. Quartz pseudomorphs after coesite occur as inclusions in garnet.The gneisses of the Donghai area have been subjected to multistage recrystallization and exhibit a closewise P-T evolution  相似文献   
45.
Multipath influence on code range under static condition is described firstly in this paper, and the problem that to what extent the phase-aided smoothing can mitigate multipath interference is detailed. Some problems regarding smoothing and mitigation are discussed. Suggestions based on the analysis has been made.  相似文献   
46.
Introduction Europe's mountains cover nearly half of the continent's area (Price et al. 2004) and land cover varies significantly (European Commission 2004). In most massifs, except for Sicily, southern Greece, and the British Isles, forest cover is dominant. In northern Europe, grassland is proportionately more important, and much of the mountains of the British Isles is covered by moorland. In central and southern Europe, arable land is of far greater importance than grassland, with Med…  相似文献   
47.
遥感影像正射纠正的GPU-CPU协同处理研究   总被引:1,自引:0,他引:1  
提出了一种基于CUDA的遥感影像正射纠正GPU-CPU协同处理方法,以实现重采样操作的GPU细粒度并行化。根据GPU的并行结构和硬件特点,采用执行配置优化技术提高warp占有率,利用共享存储器优化减少对效率低下的全局存储器中坐标变换系数的重复访问,通过纹理存储器代替全局存储器优化对原始影像数据的访问。实验结果表明,并行算法能够充分发挥GPU的并行处理能力,利用GeForce 9500 GT显卡,对大小为6 000像素×6 000像素的全色影像进行多项式纠正对比实验,最邻近灰度内插重采样和双线性灰度内插重采样的最终加速比分别能够达到8倍和10倍以上。  相似文献   
48.
The Aoyougou ophiolite lies in an early Palaeozoic orogenic belt of the western North Qilian Mountains, near the Aoyougou valley in Gansu Province, northwestern China. It consists of serpentinite, a cumulate sequence of gabbro and diorite, pillow and massive lavas, diabase and chert. Ages of 1840±2 Ma, 1783±2 Ma and 1784±2 Ma on three zircons from diabase, indicate an early Middle Proterozoic age. The diabases and basalts show light rare-earth element enrichment and have relatively high TiO2 contents, characteristic of ocean island basalts. All of the lavas have low MgO, Cr, Ni contents and Mg numbers indicating a more evolved character. They are believed to have been derived from a more mafic parental magma by fractionation of olivine, Cr-spinel and minor plagioclase. Based on the lava geochemistry and regional geology, the Aoyougou ophiolite was probably believed to have formed at a spreading centre in a small marginal basin. Subduction of the newly formed oceanic lithosphere in the Middle Proteroz  相似文献   
49.
本文首次提出剩余视极化率异常的概念和求 取公式。利用已知焦家式深部金矿床上所 测得大、 小两种极距激电中梯视极化率ηα,而求得的剩余视 极化率ηαsy,经与已知深部矿床对比,发现其ηαsy异 常具有单纯反映矿体的能力,而与破碎带内的强蚀 变岩石所形成的极化率异常无关。  相似文献   
50.
笔者在过去所研究地图模糊矩阵模型的基础上,进一步探讨了建立地图模糊矩阵模型问题,通过矩阵运算来对地图学中有关制图综合、图象变换等概念给出了数学定义,从而使概念表述数学化。  相似文献   
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