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It envinces that sea level rise aggravates low-lying terrain inundation, storm surges, beach erosion, and other ecological damages. The developed agricultural system in the Pearl River Delta is at a high risk to floods; and, in light of the tactical significance of the Guangdong-Hong Kong-Macao Greater Bay Area and its high vulnerability to sea level rise and storm surges, it urgently requires to study their impacts on the agricultural areas in this region. Taking Nansha District, Guangzhou City, Guangdong Province, China as the study area, this study builds a vulnerability evaluation model of agricultural areas with the Source-Pathway-Receptor-Consequence framework using an indicator system upon exposure, sensibility, and adaptation, and quantitatively predicts the inundation risk level, financial loss, and vulnerability patterns of varied scenarios of sea level rise superimposed with storm surges with the ArcGIS. The main findings include 1) the stimulated proportion of inundated areas in minimum-risk and maximum-risk scenarios is 73.38% and 87.96% respectively, and the estimated financial loss in both scenarios is RMB 3,897.3855 million and 7,140.4979 million, respectively; 2) the central Nansha will suffer from a higher inundation risk, and the northern and southern agriculatural parts within the study area have a higher vulnerability to flood disasters. Resilience strategies—through defense, adaptation, or relocation—for each vulnerable zone are then proposed accordingly. 相似文献
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分布式空间数据分片与跨边界拓扑连接优化方法 总被引:2,自引:0,他引:2
研究分布式空间数据库(distributed spatial database,简称DSDB)中数据按区域分片时的跨边界片段拓扑连接查询问题,并提出相应的优化方法.首先研究了分布式环境下的空间数据的分片与分布,提出了空间数据分片的扩展原则:空间聚集性、空间对象的不分割性、逻辑无缝保持性.然后,将区域分割分片环境下的片段连接分为跨边界和非跨边界两类;同时,将拓扑关系分为两类,重点研究跨边界的两类片段拓扑连接.提出了跨边界空间片段拓扑连接优化的两个定理,并给出了证明.以此为基础,给出了跨边界空间拓扑连接优化规则,包括连接去除规则和连接优化转化规则.最后设计了详细的实验,对自然连接策略、半连接策略以及所提出的连接策略进行效率比较,结果表明,所提出的方法对跨边界连接优化有明显优势.因此,所提出的理论和方法可以用于分布式跨边界拓扑关系查询的优化. 相似文献
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评价油田注水开发效果,始终贯穿于油田开发的全过程,为了更客观、全面地评价开发效果,在单指标评价的基础上应用模糊数学理论建立了模糊综合评价模型。利用指标权重,综合不同单指标评价对中高渗透油藏开发效果评价分类。 相似文献
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三氢化铝制备工艺及稳定性研究进展 总被引:1,自引:0,他引:1
综述了三氢化铝(AlH3)的晶体形态特征,以及α-AlH3的性质、合成方法、表征和稳定化方法,着重讨论了获得高质量α-AlH3结晶的条件和操作方式。 相似文献
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当才华横溢的Carole还住在家乡普罗旺斯的时候.她的画作中呈现最多的居然是中国的山水田园.正因为这份挥之不去的情愫,才成就了如今这个圆梦般的居所。 相似文献