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881.
基于GIS的福州应急避难所空间格局评价 总被引:1,自引:0,他引:1
日益凸显的突发性自然灾害对城市应急管理提出了更高的要求,应急避难所是其重要基础设施之一.本研究利用福州市社区尺度的人口统计数据建立高精度的人口密度分布图,根据应急避难所的容纳人数与人口密度图动态缓冲区分析计算其服务能力空间范围,对研究区内21个避难所的空间格局进行评价.结果表明,福州城区避难所建设数量不足,空间分布不均,人口服务辐射能力弱.针对福州城区避难所空间分布现状,分析了主要的影响因素,对福州城区应急避难场所选址提出了进一步优化建议,认为在人口分散区的避难所应该增加数量,适当减小规模;而在人口稠密区则可增加规模适中的避难所建设. 相似文献
882.
打水沟为宝兴河右岸的一级支流,位于宝兴县城城区,流域面积1.01 km2,主沟长度1.85 km,主沟比降640‰.受芦山“4·20”地震的影响,流域中下游直接引发了大量的崩滑体,加之地形陡峻,且位于青衣江-鹿头山暴雨区边缘,极容易发生泥石流.一旦发生泥石流,将会对沟口建筑和人员的安全造成巨大危害.通过对打水沟地震前后遥感影像的解译,结合野外考察,综合判定该沟为地震触发的潜在性泥石流沟.进一步分析估算,由于地震震动导致流域内发育6处崩塌体,总面积20375 m2,松散固体物质总量为15.20×l04m3.在分析泥石流形成条件与发展趋势的基础上,提出了打水沟泥石流减灾方案,并对泥石流排导槽梯形最佳过流横断面进行了设计.通过计算分析得到,在排泄设计标准的泥石流时,排导槽的最佳过流断面宽度为2.38 m,深度为2.23 m. 相似文献
883.
G. B.M. Heuvelink Z. Jiang S. De Bruin C. J.W. Twenhöfel 《International journal of geographical information science》2013,27(3):365-382
In case of a nuclear accident, decision makers rely on high-resolution and accurate information about the spatial distribution of radioactive contamination surrounding the accident site. However, the static nuclear monitoring networks of many European countries are generally too coarse to provide the desired level of spatial accuracy. In the Netherlands, authorities are considering a strategy in which measurement density is increased during an emergency using complementary mobile measuring devices. This raises the question, where should these mobile devices be placed? This article proposes a geostatistical methodology to optimize the allocation of mobile measurement devices, such that the expected weighted sum of false-positive and false-negative areas (i.e. false classification into safe and unsafe zones) is minimized. Radioactivity concentration is modelled as the sum of a deterministic trend and a zero-mean spatially correlated stochastic residual. The trend is defined as the outcome of a physical atmospheric dispersion model, NPK-PUFF. The residual is characterized by a semivariogram of differences between the outputs of various NPK-PUFF model runs, designed to reflect the effect of uncertainty in NPK-PUFF meteorological inputs (e.g. wind speed, wind direction). Spatial simulated annealing is used to obtain the optimal monitoring design, in which accessibility of sampling sites (e.g. distance to roads) is also considered. Although the methodology is computationally demanding, results are promising and the computational load may be considerably reduced to compute optimal mobile monitoring designs in nearly real time. 相似文献
884.
四川西部高山峡谷地貌发育,山高林密且地质环境恶劣,区内林草资源丰富,森林火灾多发、易发、频发,灾害应急处置难度大,防控任务重。国产高分系列卫星影像具有时空分辨率高、载荷类型多、机动性强、幅宽范围大、成像迅速等优点,对川西地区森林防灭火、灾害应急处置及防灾减灾等有明显优势。以2021年四川九龙县三岩龙乡“4·08”森林火灾为例,利用国产高分系列卫星数据分别对森林火灾初期、中期及晚期开展应急处置,包括快速解译林火火灾救援要素(初期)、感知亮温异常态势(中期)、跟踪监测过火区动态(中期)、结合火场需求提供应急扑救部署建议(中期)、开展灾损解译评估(晚期)及火后泥石流易发性评价(火后)等,结果表明国产高分系列卫星对森林火灾应急处置的全流程应用具有实践指导意义。 相似文献
885.
We obtained a catalog of early aftershocks of the 2013 Lushan earthquake by examining waveform from a nearby station MDS which is 30.2 km far away from the epicenter, and then we analyzed the relation between aftershock rate and time. We used time-window ratio method to identify aftershocks from continuous waveform data and compare the result with the catalog provided by China Earthquake Networks Center (CENC). As expected, a significant amount of earthquakes is missing in CENC catalog in the 24 h after the main shock. Moreover, we observed a steady seismicity rate of aftershocks nearly in the first 10,000 s before an obvious power-law decay of aftershock activity. We consider this distinct early stage which does not fit the Omori law with a constant p (p - 1) value as early aftershock deficiency (EAD), as proposed by previous studies. Our study suggests that the main shock rupture process is different from aftershocks' processes, and EAD can vary in different cases as compared to earthquakes of strike-slip mechanism in California. 相似文献
886.
Earthquake early warning (EEW) systems are one of the most effective ways to reduce earthquake disaster. Earthquake magnitude estimation is one of the most important and also the most difficult parts of the entire EEW system. In this paper, based on 142 earthquake events and 253 seismic records that were recorded by the KiK-net in Japan, and aftershocks of the large Wenchuan earthquake in Sichuan, we obtained earthquake magnitude estimation relationships using the τe and Pa methods. The standard variances of magnitude calculation of these two formulas are ±0.65 and ±0.56, respectively. The Pd value can also be used to estimate the peak ground motion of velocity, then warning information can be released to the public rapidly, according to the estimation results. In order to insure the stability and reliability of magnitude estimation results, we propose a compatibility test according to the natures of these two parameters. The reliability of the early warning information is significantly improved though this test. 相似文献
887.
以中国知网期刊全文数据库(CNKI)和维普科技期刊全文数据库为基础,统计分析了四川省地震局1992~2011年期间发表的地震期刊中文学术论文的情况。四川省地震局20年间共计发表论文1171篇,平均每年产出地震期刊学术论文58.5篇,以四川省地震局为第一署名单位论文925篇,平均每年46篇,论文数量逐年分布呈上升趋势,且与强震活动相关;论文刊载于74种中文科技期刊,总频次大于20次的高频期刊有8个;论文基金资助率逐年增加。论文统计结果显示四川地震科技研究工作一直在持续进步,在科技发展的主动性和创新性以及基层台站科研方面需进一步加强。 相似文献
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