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建立了测井多媒体数据库,论述了数据库的实现方法及动态复杂查询的实现,为进行测井数据查询提供了简便高效的途径。 相似文献
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等效偏移距偏移(EOM)成像方法将克希霍夫时间偏移的双平方根方程转化为一个单平方根方程,使输入采样在没有发生时移的情况下映射到以等效偏移距为变量的共散射点道集上,使散射能量按照双曲线规律分布。然后通过克希霍夫动校正和适用在共散射点道集上的叠加来完成偏移成像。基于等效偏移距叠前地震偏移(EOM)的基本理论,对CSP道集的抽取过程进行模拟实现,并对模型进行速度分析,实现偏移成像。 相似文献
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颜色的均匀性是评价颜色空间的优劣和影响其选择使用的重要指标之一,其色差计算值对于颜色再现评价的再现过程控制具有重要作用。在中国颜色体系的基础上,分别从明度、色相和彩度的角度对颜色空间C IEL*a*b*、C IEL*u*v*、NC-IIIC、L*a*b*-N和C IECAM02-UCS的均匀性进行了分析和比较。结果表明,这几种颜色空间明度的均匀性都比较理想,而色相和彩度的均匀性较差。就这5种颜色空间而言,NC-IIIC和L*a*b*-N颜色空间均匀性要优于其他颜色空间。 相似文献
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景观生态建设与生物多样性保护 总被引:24,自引:2,他引:22
21世纪的景观生态学应该对环境建设有设计能力的学科。遵循适应自然、互利共生、调整结构改善功能与局部控制协调整体等景观生态建设的原理进行景观生态建设是积极的对生物多样性予以保护。 相似文献
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INVESTIGATION OF STATUS AND DEMAND ON PUBLIC SERVICE OF EARTHQUAKE DISASTER MITIGATION IN CHINA 下载免费PDF全文
In order to make a comprehensive and systematic evaluation of the status and demands of public service of earthquake disaster mitigation, we launched an investigation with Social Opinion Polling Center of National Bureau of Statistics on the current situation of public service of earthquake disaster mitigation and the demands for it in 2018. The investigation was conducted for 18~75-year-old residents for both urban and rural areas in 31 provinces of China mainland using the Computer Assisted Telephone Interview(CATI)method and 20 078 valid samples were received in total. The questionnaire mainly includes two parts: the current situation assessment and the demand survey. The assessment of public service status consists of five indicators: earthquake emergency drill, knowledge publicity of earthquake prevention and disaster reduction, acquisition of earthquake information, reliability of information released by earthquake agencies, and overall satisfaction. The results indicate that only 27.4% of public have participated the earthquake emergency drill, and 73.5% of public have learned some knowledge about earthquake prevention and disaster reduction in different level. It shows that rural residents have a lower level of scientific knowledge of earthquake disaster mitigation although the rural residents have a higher level of satisfaction. Meanwhile, 82.9% of the public are very concerned about earthquake-related information, and the earthquake information acquisition convenience score is 81.51 points(the full score is 100 points). At present, TV is still the most popular way to obtain the earthquake-related information, besides that, network and the new media app such as Wechat and Weibo play a more and more important role. In terms of the reliability of official information published by the earthquake administration, the score is 83.69 points which indicates that the public tend to believe in official departments. Furthermore, the degree of satisfaction evaluation of public service of earthquake disaster mitigation is marked 76.44 points which shows that there is still much room for improvement. The more educated the public, the less satisfied they are with the public service of earthquake prevention and disaster reduction. The results also show that 51.81% of the public are willing to obtain earthquake warning information at their own expense. As for the demand, the most expectative services for the public are post-earthquake rescue and reconstruction, earthquake warning, and house earthquake resilience test. The results of the investigation may provide some reference for the government to provide better services of earthquake disaster mitigation and to make scientific knowledge popularization in a more scientific way. 相似文献
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The effects of wave–current interactions on ocean surface waves induced by Hurricane Hugo in and around the Charleston Harbor and its adjacent coastal waters are examined by using a three-dimensional (3D) wave–current coupled modeling system. The 3D storm surge modeling component of the coupled system is based on the Princeton Ocean Model (POM), the wave modeling component is based on the third generation wave model, Simulating WAves Nearshore (SWAN), and the inundation model is adopted from [Xie, L., Pietrafesa, L. J., Peng, M., 2004. Incorporation of a mass-conserving inundation scheme into a three-dimensional storm surge model. J. Coastal Res., 20, 1209–1223]. The results indicate that the change of water level associated with the storm surge is the primary cause for wave height changes due to wave–surge interaction. Meanwhile, waves propagating on top of surge cause a feedback effect on the surge height by modulating the surface wind stress and bottom stress. This effect is significant in shallow coastal waters, but relatively small in offshore deep waters. The influence of wave–current interaction on wave propagation is relatively insignificant, since waves generally propagate in the direction of the surface currents driven by winds. Wave–current interactions also affect the surface waves as a result of inundation and drying induced by the storm. Waves break as waters retreat in regions of drying, whereas waves are generated in flooded regions where no waves would have occurred without the flood water. 相似文献
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数字化精密水准测量仪器在水准及形变测量领域中起着极其重要的作用,而对数字水准仪的计量检定工作是使其正常运行的前提,针对其检定项目室内化的难题,介绍了一种国产新型数字水准仪的室内检定装置. 相似文献