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1.
鉴于恐怖袭击事件的破坏性和危害性,对恐怖袭击事件进行分析和预测能够为相关部门组织反恐行动提供有效的理论支持,基于恐怖袭击事件发生的时间和地区因素,分析恐怖袭击事件的时空特性,建立了基于灰色理论的恐怖袭击事件预测模型,并根据恐袭事件季度性的特点,分季度对建立的模型进行了案例分析,通过计算和Matlab仿真证实了该模型的可行性,对反恐措施的制定具有一定的参考和指导意义.  相似文献   

2.
基于GTD全球恐怖主义数据库,共研究四个方面的问题:对恐怖袭击事件分级,识别恐怖袭击事件制造者,分析未来反恐态势以及各个地区反恐应急能力.首先,建立了恐怖袭击事件危害性评价体系,运用层次分析法确定了指标权重,将危害程度分成了1-5等级;其次,采用基于遗传模拟退火算法的聚类算法,对选出的代表事件进行排序,基于灰色关联分析,分析了各聚类中心事件与要求事件的关联程度.再次,对近三年的恐怖袭击事件进行分类与预测分析.最后,通过建立模型,量化了恐怖组织单次恐怖袭击水平与地区反恐应急能力.结果表明:选取了近十年来十大恐怖事件大部分为国际恐怖事件,恐怖袭击事件与相关袭击事件制造者相关程度较高,全球恐怖袭击事件数量有所下降,应急能力最强的地区为西欧,最弱的为中亚,且恐怖袭击次数与反恐应急能力处于较强关联性.  相似文献   

3.
近年来,全球范围内恐怖袭击事件的发生日益频繁,已经成为许多国家和地区所面临的主要安全问题.首先建立了全球恐怖袭击事件危险性分级指标体系,并基于多模块模糊贝叶斯网络来建立一个基于观测事件"后验概率"的推理模型,从而解决信息不确定时恐怖袭击事件的危险性分级.其次,利用FCM聚类模型对恐怖袭击事件的危险度进行聚类分析,从而依据事件特征对犯罪嫌疑人进行准确锁定.然后,建立了贝叶斯网络恐怖活动预测模型,为全球反恐态势提供有效预测,并利用ArcGIS热点图分析各地区恐怖袭击事件的时空特性.最后,基于VAR模型揭示了不同区域之间在恐怖袭击事件发生时跨区域间的相互影响关系,并提出了相应的反恐建议.  相似文献   

4.
近年来,恐怖袭击愈演愈烈,合理分析判断恐怖袭击事件对于预防应急和安全救治可以发挥重大作用.根据用特征选择方法筛选出的主要属性,结合求出的属性权重构建了线性函数模型,以量化求出恐怖袭击事件的危害值,并以此构建恐怖袭击事件的量化分级模型.同时,还利用数据分析方法对恐怖袭击事件和反恐态势进行了分析.  相似文献   

5.
运用数据挖掘的方法,对全球恐怖主义数据库(以下简称GTD)进行了量化分析.建立了基于KNN邻近算法的恐怖袭击事件量化分级模型和基于K-means聚类算法的恐怖袭击事件分类模型.此外,对近三年来恐怖袭击事件发生的主要原因、时空特性、蔓延特性以及级别分布规律进行了分析.最后,基于建立的模型和分析结论,对未来全球和某些重点地区的反恐态势进行了预测分析,给出了具有针对性的建议.  相似文献   

6.
恐怖主义是人类的共同威胁,利用数据挖掘可以为反恐防恐提供有价值的信息支持.基于数据挖掘的思路,从恐怖袭击事件中提取能描述危险程度的特征属性,构建量化分级模型,并考虑准确率评价指标进行优化.通过组内平方和法分析改进高斯混合模型(GMM),对恐怖组织进行聚类分析,侦查出潜在最相关的嫌疑人.建立相关模型结合统计分析,得到恐怖袭击发生的主要原因、时空特性和蔓延特性,并对未来全球反恐态势进行预测,帮助反恐组织提高反恐的精准性和打击能力.  相似文献   

7.
首先基于近20年的全球恐怖主义数据库采用主成分分析和模糊综合评价模型对恐怖袭击事件的危害程度进行评价,对比分析后选取其中较优者即主成分分析模型作为评价结果,接着用极差等间隔分级法和剔除极端事件后极差平均间隔分级法对恐怖袭击的危害程度从高到低分为一至五级,综合比较后选取极差平均间隔分级法对其危害等级进行划分,该划分方法危害等级越小事件危害性越大.同时选取中国、美国、英国、印度、南非、澳大利亚6个典型国家,结合主成分综合评价值对其国家安全度进行定量评价.该评价及等级划分方法适用于对全球恐怖袭击事件进行危害评价及分级,同时可对任意国家的安全度进行评价.最后采用经纬度距离近似公式建立最短距离无约束最优化模型,给出反恐基地设置建议,可确定局部地区如中东地区的反恐基地位置.  相似文献   

8.
如果每个事件发生的概率只与构成该事件的区域的长度、面积或体积成比例,则称这样的概率模型为几何概型.解决几何概型问题,关键是构造出随机事件所对应的几何图形,并对几何图形进行相应的几何度量.下面对几何概型的五类题型的求解进行归纳,以供参考.  相似文献   

9.
在复发事件的统计分析中,事件的平均发生个数可能比其强度函数或危险率函数更具可解释性.为了评价协变量对复发事件的影响,许多学者考虑了复发事件的边际比例均值模型.然而,在许多实际应用中,协变量对复发事件不仅具有均值比例效应,而且还可能会加速或减缓复发事件的发生,即协变量对复发事件均值过程具有时间尺度效应.在多类型复发事件数据框架下,考虑一类广泛的加速均值模型.利用估计方程方法,获得了该模型中未知参数的估计,并且建立了所给估计的渐近性质.进一步通过模拟研究证实所提方法的优良表现.  相似文献   

10.
简述2018年中国研究生数学建模竞赛C题"对恐怖袭击事件记录数据的定量分析"的命题背景、数据来源和设计思路,并对参赛论文所涉及的有关问题和取得的成果进行评注.  相似文献   

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12.
张丽娜  吴建华 《数学进展》2008,37(1):115-117
One of the most fundamental problems in theoretical biology is to explain the mechanisms by which patterns and forms are created in the'living world. In his seminal paper "The Chemical Basis of Morphogenesis", Turing showed that a system of coupled reaction-diffusion equations can be used to describe patterns and forms in biological systems. However, the first experimental evidence to the Turing patterns was observed by De Kepper and her associates(1990) on the CIMA reaction in an open unstirred reactor, almost 40 years after Turing's prediction. Lengyel and Epstein characterized this famous experiment using a system of reaction-diffusion equations. The Lengyel-Epstein model is in the form as follows  相似文献   

13.
In this paper, we study the explicit representation and convergence of (0, 1; 0)-interpolation on infinite interval, which means to determine a polynomial of degree ≤ 3n - 2 when the function values are prescribed at two set of points namely the zeros of Hn(x) and H′n(x) and the first derivatives at the zeros of H′n(x).  相似文献   

14.
As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years (2001-2005). The main topics are: convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.  相似文献   

15.
We study a class of self-similar processes with stationary increments belonging to higher order Wiener chaoses which are similar to Hermite processes. We obtain an almost sure wavelet-like expansion of these processes. This allows us to compute the pointwise and local Hölder regularity of sample paths and to analyse their behaviour at infinity. We also provide some results on the Hausdorff dimension of the range and graphs of multidimensional anisotropic self-similar processes with stationary increments defined by multiple Wiener–Itô integrals.  相似文献   

16.
Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.  相似文献   

17.
It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary.  相似文献   

18.
正Guest Editors:Hong Chen,Shanghai Jiao Tong University,Shanghai,China Guohua Wan,Shanghai Jiao Tong University,Shanghai,China David Yao,Columbia University,New York,USA Scope:Healthcare delivery worldwide has been fraught with high cost,low efficiency and poor quality of patient care service.For the field of operations research(OR),healthcare offers some of the biggest challenges as well as best opportunities in  相似文献   

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20.
Due to the resolution of current laser technology, the accuracy of corneal topography as measured by the videokeratoscope is no longer adequate to provide precise enough data for refractive surgery or for the fitting of customized contact lenses. We present an algorithm for recovering corneal topography that makes use of modern differential geometric techniques and numerical descent in Sobolev spaces. We believe this algorithm may be used with the photo- and videokeratoscope to increase the accuracy of the recovered corneal topography.  相似文献   

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