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针对传统地震数据机房存在业务扩展成本高且周期长、维护繁琐、无法保障重要业务系统的无故障连续运作等问题,采用虚拟化云计算技术,实现地震行业网的私有云服务。华为FusionCompute云服务系统将主机、存储等物理资源虚拟化,并整合为统一资源,供多个虚拟机使用,行业专网内运维人员通过用户接口远程访问云平台,在虚拟机上可快速、高效地按需搭建业务系统。地震私有云平台不仅减少业务扩展运营期间的设备采购、系统搭建、运行维护等人力和物力投入,且通过FusionCompute的迁移技术,实现业务系统的"零宕机"服务。 相似文献
944.
GIDS空间插值法估算云下地表温度 总被引:1,自引:2,他引:1
选用陆面区域温度最佳空间插值法—梯度距离平方反比法(GIDS),为近似估算云下地表温度提供了可能。实验选取暖季南京江宁地区ETM+影像和ASTERGDEMV1高程数据,探索分析GIDS估算云下地表温度的可行性和可信性。对14种空间大小云覆盖区实验研究表明:利用GIDS插值估算云下地表温度具有可行性,且估算误差随着云覆盖区范围增大而增加,其最大MAE<0.9℃,最大RMSE<1.2℃,并在云覆盖区小于100×100像元时,最大MAE<0.8℃、RMSE<1℃;插值精度与最近邻无云像元典型代表性、区域内空间复杂度和地表覆盖类型均有关,存在不稳定性和动态性;云下NDVI均方差与MAE、RMSE有着一致变化趋势,借助NDVI均方差指示云下地表空间异质性及NDVI–LST负相关性,可对插值结果进行可信性评判,以避免插值结果盲目应用,推进和提升地表温度产品应用价值。 相似文献
945.
龚明杰 《测绘与空间地理信息》2022,45(1):198-199
为解决大范围复杂山区DEM生产困难的问题,提出利用机载LiDAR点云数据构建DEM.本文对机载LiDAR数据处理流程及其在复杂山区的具体应用进行分析,主要利用LiDAR数据处理软件对点云数据进行内业DEM生产并编辑最终得到符合项目要求的数字高程模型数据,结果证明该方法可行. 相似文献
946.
Accurate and reliable methods for quantifying grain size are important for river science, management and in various other sedimentological settings. Remote sensing offers methods of quantifying grain size, typically providing; (a) coarse outputs (c. 1 m) at the catchment scale where individual grains are at subpixel level, or; (b) fine resolution outputs (c. 1 mm) at the patch scale. Recently, approaches using unmanned aerial vehicles (UAVs) have started to fill the gap between these scales, providing hyperspatial resolution data (< 10 cm) over reaches a few hundred metres in length, where individual grains are at suprapixel level. This ‘mesoscale’ is critical to habitat assessments. Most existing UAV‐based approaches use two‐dimensional (2D) textural variables to predict grain size. Validation of results is largely absent however, despite significant differences in platform stability and image quality obtained by manned aircraft versus UAVs. Here, we provide the first quantitative assessment of the accuracy and precision of grain size estimates produced from a 2D image texture approach. Furthermore, we present a new method which predicts subaerial gravel size using three‐dimensional (3D) topographic data derived from UAV imagery. Data is collected from a small gravel‐bed river in Cumbria, UK. Results indicate that our new topographic method gives more accurate measures of grain size (mean residual error ‐0.0001 m). Better results for the image texture method may be precluded by our choice of texture measure, the scale of analysis or the effects of image blur resulting from an inadequate camera gimbal. We suggest that at our scale of assessment, grain size is more strongly related to 3D variation in elevation than to the 2D textural patterns expressed within the imagery. With on‐going improvements, our novel method has potential as the first grain size quantification approach where a trade‐off between coverage and resolution is not necessary or inherent. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
947.
During a mainshock-aftershock (MSAS) sequence, there is no time to retrofit structures that are damaged by a mainshock; therefore, aftershocks could cause additional damage. This study proposes a new approach to develop state-dependent fragility curves using real MSAS records. Specifically, structural responses before and after each event of MSAS sequences are used to obtain statistical relationships among the engineering demand parameter prior to the seismic event (pre-EDP), the intensity measure of the seismic event (IM), and the engineering demand parameter after the seismic event (post-EDP). The developed fragility curves account for damage accumulation, providing the exceeding probability of damage state (DS) given the IM of the event and the DS of the structure prior to the seismic excitation. The UBC-SAWS model, which was developed for wood-frame houses in British Columbia, Canada, is considered as a case study application. Results indicate that for the examined structural typology, state-dependent fragility curves based on residual interstorey drift ratio (pre-EDP), peak ground velocity (IM), and maximum inter-storey drift ratio (post-EDP) are the best choice to characterise the cumulative damage effect. An illustration of the developed fragility curves is provided by considering a hypothetical MSAS scenario of a Mw 9.0 Cascadia mainshock triggering a Mw 6.0 crustal event in the Leech River fault, affecting wooden houses in Victoria, Canada. The MSAS scenario increases Yellow tags (restricted access) by 12.3% and Red tags (no access) by 4.8%. 相似文献
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在数字嘉兴建设成果的基础上,本文结合"智慧嘉兴"时空大数据与云平台试点项目建设,探讨构建全市统一的智慧城市时空大数据与云平台,介绍了平台总体架构、技术路线设计、系统实现、示范应用及关键技术分析,根据运行实践证明,该平台能够为全市政府部门、企事业单位及社会公众提供权威、统一、可靠的智慧时空信息服务. 相似文献
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