为了对铁路系统涉恐事件进行风险管理,遏制铁路系统恐怖袭击事件的发生,提出基于DBSCAN(density-based spatial clustering of applications with noise)算法的铁路系统恐怖袭击风险评估方法。首先对1970—2017年发生的铁路系统恐怖袭...为了对铁路系统涉恐事件进行风险管理,遏制铁路系统恐怖袭击事件的发生,提出基于DBSCAN(density-based spatial clustering of applications with noise)算法的铁路系统恐怖袭击风险评估方法。首先对1970—2017年发生的铁路系统恐怖袭击案件进行统计分析,然后采用DBSCAN算法对恐怖袭击发生次数、死亡人数和受伤人数3项风险评价指标进行聚类分析,最终客观计算出几类袭击方式、袭击目标和86个国家的风险。结果表明,该方法的分析过程避免了人工赋值和专家打分策略,评估结果更具客观性和真实性,适用于反恐情报工作的风险评估领域。展开更多
Multiple channels are available for use in IEEE 802.11.Multiple channels can increase the available network's capacity,and how to efficiently assign these available channels to optimize the network performance is ...Multiple channels are available for use in IEEE 802.11.Multiple channels can increase the available network's capacity,and how to efficiently assign these available channels to optimize the network performance is a challenge.We survey current techniques to solve the problem,and category the techniques single-radio,multi-radio,cross-layer multi-channel assignment.This paper also discusses some interesting issues at last.展开更多
文摘为了对铁路系统涉恐事件进行风险管理,遏制铁路系统恐怖袭击事件的发生,提出基于DBSCAN(density-based spatial clustering of applications with noise)算法的铁路系统恐怖袭击风险评估方法。首先对1970—2017年发生的铁路系统恐怖袭击案件进行统计分析,然后采用DBSCAN算法对恐怖袭击发生次数、死亡人数和受伤人数3项风险评价指标进行聚类分析,最终客观计算出几类袭击方式、袭击目标和86个国家的风险。结果表明,该方法的分析过程避免了人工赋值和专家打分策略,评估结果更具客观性和真实性,适用于反恐情报工作的风险评估领域。
基金spported by the National Natural Science Foundation of China ( No. 60973139, 60773041 )Postdoctoral Foundation (No. 0801019C,20090451240, 20090451241)+2 种基金Science&Technology Innovation Fund for Higher Education Institutions of Jiangsu Province( No.CX09B_153Z,CX08B-086Z )Six Projects Sponsoring Talent Summits of Jiangsu Province(No. 2008118)the project of NJUPT(No.NY207135)
文摘Multiple channels are available for use in IEEE 802.11.Multiple channels can increase the available network's capacity,and how to efficiently assign these available channels to optimize the network performance is a challenge.We survey current techniques to solve the problem,and category the techniques single-radio,multi-radio,cross-layer multi-channel assignment.This paper also discusses some interesting issues at last.