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1.
采用灾损度DLD和环境不稳定度EI两个要素,构建了灾害经济损失指数DELI(灾损度指数)指标对灾害经济损失进行评估,并应用它对福建省洪涝灾害经济损失趋势变化进行了分析.研究表明:利用灾损度指数对灾害经济损失评估的方法是可行的,不受灾害发生的时间和地点限制,可比性强,资料信息源多,计算方便,适用范围广;福建省洪涝灾害灾损度指数呈波动上升趋势,反映出福建洪涝灾情加重、灾害本身损失加大与福建省环境不稳定度加大有关,和实际情况相符.  相似文献   

2.
感知器算法在台风风暴潮灾情等级评估中的应用   总被引:7,自引:0,他引:7  
风暴潮灾害每年都给我国沿海地区造成巨大的经济损失.在前人研究的基础上,引入风暴潮灾情等级的模式识别思想,运用感知器方法的理论及其算法,并以广东省湛江地区为例,建立了该地区的台风风暴潮灾情等级判别函数,经还原检验和判别预测获得满意的结果,证明该方法用于台风风暴潮灾情等级判别是可行的.这对于实现风暴潮灾情等级的快速评估,为抢险救灾的人力、财力和物力分配提供依据.  相似文献   

3.
福建省台风灾害直接经济损失预评估模型   总被引:3,自引:0,他引:3  
基于2000—2009年对福建省造成灾害损失的22个台风数据,将台风分为气象型灾害和混合型灾害,利用数理统计的方法建立台风灾害直接经济损失预评估模型,在得到致灾因子和损失因子的多项式拟合关系基础上,进行了台风损失的悲观估计和乐观估计,并对台风灾害的影响等级进行了评估.研究结果显示该模型具有较高的拟合率,由误差分布和实际评估结果计算的模型的有效率均达到80%以上,能够较好地预评估台风可能造成的直接经济损失并能有效地分析台风灾害的趋势;灾害等级预报的准确性稍低于灾害经济损失预报的准确性,但总体属于同一水平.模型的建立可为防灾减灾提供科学依据,具有实际意义.  相似文献   

4.
全球气候变化背景下,海平面上升和温室气体的大量排放加剧了台风风暴潮损失,构建准确的损失评估模型对海洋防灾减灾工作有重大现实意义。本文选用1995-2020年50组广东省台风风暴潮进行试验,基于气候变化和风险评估理论建立台风风暴潮损失评估指标体系,使用主成分分析筛选输入因子,进行RBF神经网络和支持向量回归模型的直接经济损失和海水养殖受灾面积评估,通过比较有无气候变化指标评估模型的结果,验证了气候变化是影响灾害损失的重要因素。采用熵权法组合RBF神经网络和支持向量回归模型进行直接经济损失评估,对比单一模型发现组合模型有更好的预测精度,为防灾减灾事业提供了有效的损失评估方式。  相似文献   

5.
利用1991~2010年云南省洪涝灾害灾情数据,基于灰色系统理论计算灾情灰色关联度,对洪涝灾害进行定量评估,并分析其变化趋势.结果表明:近20 a间云南洪涝灾害损失1990年代后期为一个高峰期,1998年最重;受灾人口、死亡人口、损坏房屋、农作物受灾面积的变化趋势较为一致,出现峰值后呈下降趋势,而直接经济损失的变化趋势不明显;1998、1999年划为极重灾年,1996、1997、2001年为重灾年.  相似文献   

6.
1921~2000年上海市地面沉降灾害经济损失评估   总被引:11,自引:0,他引:11  
首次从动态性、可计量性、综合性、稳健性和可分性等评估原则出发 ,综合运用终值法、影子工程法、重置成本法、工程费用法、灾情比较法、间接损失与直接损失比例法和权重分解法等评估方法 ,对 192 1~ 2 0 0 0年上海市地面沉降灾害所造成的经济损失进行了科学评估 ,其经济损失高达 2 94 3.0 7亿元 ,平均年损失 36 .8亿元 .  相似文献   

7.
以1816号台风"贝碧嘉"为例,本文选择了依据可拓理论建立的海南台风灾害实时评估系统,对1816号台风"贝碧嘉"给海南造成的灾害进行了灾前、灾中和灾后的实时动态评估,且通过与民政部门的实际灾情统计的对比分析验证了评估结果的准确性.  相似文献   

8.
基于灰色关联分析方法,考虑灾情因子指标之间的影响,将加权灰色关联度作为评价准则建立灾情评估模型.利用1990-2007年(除2004年)17年对华南影响较大的热带气旋灾害资料,选取死亡人数、受灾人数、农田受灾面积、房屋倒塌间数和直接经济损失5个指标对灾情进行评估.计算结果表明:基于灰色关联度确定灾情因子指标权重的方法可行有效;使用该方法所得的评价结果与实际情况基本吻合.  相似文献   

9.
洪涝灾害造成的危害广泛且复杂,合理的洪涝灾害灾情评估方法是制定有效防灾减灾措施的关键手段。根据《洪涝灾情评估标准》(SL579—2012),结合死亡人口、受灾人口、农作物受灾面积、直接经济损失、倒塌房屋、水利设施经济损失等关键影响因素,建立了洪涝灾害评价指标。综合灰色关联度分析法和熵权法,提出一种针对暴雨洪涝灾情的分级评估方法,并以2014—2018年的全国年度洪灾数据为例进行应用,结合评估结果和实际情况,提出了暴雨洪涝灾害防灾减灾工作的建议。结果表明:全国暴雨洪涝灾情熵权-灰色关联度数值高的区域集中在东南区域和西北区域,防洪防涝工作重点分别在城市防洪和沙漠防洪;2016年全国暴雨灾情熵权-灰色关联度分级属于较大洪涝灾害年。  相似文献   

10.
高蕾 《山东科学》2018,31(2):88-93
利用2009-2015年陕西省自然灾害灾情数据,结合数理统计分析方法,对该区域自然灾害进行时空特征分析,并对其灾害脆弱性进行研究。结果表明, 受灾人口、农作物受灾面积是研究区域自然灾害脆弱性的直接表现形式,灾害造成的直接经济损失是自然灾害脆弱性的间接表现形式。陕西省自然灾害脆弱性具有明显的时空分布差异性,自然灾害脆弱性较高的地区主要分布在东部,而中部的西安、铜川市是自然灾害脆弱性较低地区。该研究为防灾减灾、预报预警部门提供了决策依据。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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