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空间数据捕捉是地图制图、空间数据编辑中的一个重要的功能。快捷、高效的空间数据捕捉算法可极大地提升空间数据编辑的效率,减少时间成本。目前常用的空间查询捕捉算法往往算法复杂,I/O操作频繁,增加了计算资源的消耗,降低了运行效率。针对这些缺点,本文提出了一种新型的空间目标动态捕捉算法。该算法建立一种自适应性和动态性的格网索引机制,该机制基于区域变化提取新格网,用新格网对原有数据和新数据进行提取,并把提取结果反映到新的四叉树格网索引中,实现索引数据动态更新。通过实验对比,我们发现该算法在缩短捕捉时间、提高矢量点线面捕捉精度方面非常有效,且捕捉稳定性较高,极大地提高了外业采集人员和数据处理人员的工作效率。 相似文献
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Jianhua Hu Shaojun Liu Ruiqiang Zhang Qiong Hu 《Geotechnical and Geological Engineering》2016,34(4):1029-1035
The uniaxial compressive breaking process of energy of deep-sea Cobalt-Rich Crust was selected as researching content, and the calculation of energy conversion of breaking Cobalt-Rich Crust under loading and unloading conditions was described in detail, and also the specimens of Cobalt-Rich Crust were tested in rock mechanical testing system under the specified stressing paths. From experimental data, the elastic energy, the dissipated energy and the total inputting energy of unloading points were analyzed systematically. The conclusions are as follows: (1) the specimens of Cobalt-Rich Crust are anisotropic rock, and different testing specimens need to load different axial forces to break, and the maximum of axial force is 8KN, and the minimum is 5KN; (2) when increasing the axial force, the elastic energy, the dissipated energy and the total inputting energy of the unloading points increased nonlienearly; (3) Cobalt-Rich Crust is not the same with other ordinary elastic rock, the elastic energy is lower than the corresponding dissipated energy, and with the increasing of the axial force, the difference between two values becomes more and more. 相似文献
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Jianhua Hu Shaojun Liu Ruiqiang Zhang Qiong Hu 《Geotechnical and Geological Engineering》2016,34(5):1565-1570
Experimental study of mechanical characteristics of Cobalt-Rich Crusts was conducted by MTS815 rock mechanical testing system and MTS615 environmental chamber under temperatures of 0–150 DEG C. The relationships between temperature and peak force, peak strain, elastic modulus and other parameters are analyzed systematically. Results show that there are different mechanical properties for Cobalt-Rich Crusts under different temperatures. With the increasing of temperature, the peak force and peak strain also are gradually reduced, and the changing amplitude is not a strict linear relationship, with the changing of temperature, the amplitude of the changing is or more or less nonlinear. When the temperature is 0 or 25 DEG C, the elastic modulus of Cobalt-Rich Crusts is nearly equal, but when the temperature changes from 25 to 150 DEG C, the elastic modulus increases with the increasing of temperature. Therefore, the researching work can provide a new idea for deep-sea mining engineering, and also be a theoretical basis for deep-sea mining. 相似文献
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利用1979-2009年逐月NCEP／NCAR再分析资料和福建省66站降水资料,分析了3－4月南极涛动（AAO）的变化对后期福建前汛期（5－6月）降水的影响。结果表明：3－4月平均的AAO指数与福建前汛期降水有很好的正相关性,前期AAO偏强时,后期前汛期降水偏多,反之亦然;且AAO异常时降水的同号率为100％。对AAO异常年的分析发现,当前期AAO异常强时,后期北方冷空气活动频繁,南方暖湿气流输送强盛,在华南北部产生强烈锋生,导致福建前汛期降水偏多;反之,降水偏少。上述结论为福建前汛期降水预测提供了一条可行的新途径。 相似文献