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541.
    
A comprehensive maritime interdiction strategy to attack the insurgent's logistic system was a key element in the defeat of the Tamil Tigers. The campaign of maritime interdiction required the Sri Lankan Navy (SLN) to attack LTTE arms smuggling, sea piracy, and maritime terrorism. The SLN degraded the insurgency's robust maritime logistical network while also devising tactics to engage the maritime insurgents who reacted with swarm and suicide boat tactics. The efforts of the SLN forced the Tamil Tigers to confront the government's final land offensives with diminished resources, thus collapsing a three decades’ old insurgency in a matter of months.  相似文献   
542.
李亮  孔祥营 《指挥控制与仿真》2009,31(2):116-118,122
针对嵌入式浏览器信息传输的安全性问题和嵌入式软件的特点,介绍了SSL协议,提出了一种在嵌入式浏览器中实现对SSL协议支持的方法.通过分析影响SSL协议客户端性能的因素,对SSL的实现过程进行了适当的优化,使用会话恢复机制、只对服务器进行验证的简单握手模式、减少TCP调用次数和优化对批量数据加密算法等方法,实现了嵌入式浏览器对SSL协议的支持;并介绍了方法在嵌入式浏览器JARI_Browser中的实现过程.实际的应用验证了该方法的可行性和正确性.  相似文献   
543.
    
Passenger prescreening is a critical component of aviation security systems. This paper introduces the Multilevel Allocation Problem (MAP), which models the screening of passengers and baggage in a multilevel aviation security system. A passenger is screened by one of several classes, each of which corresponds to a set of procedures using security screening devices, where passengers are differentiated by their perceived risk levels. Each class is defined in terms of its fixed cost (the overhead costs), its marginal cost (the additional cost to screen a passenger), and its security level. The objective of MAP is to assign each passenger to a class such that the total security is maximized subject to passenger assignments and budget constraints. This paper shows that MAP is NP‐hard and introduces a Greedy heuristic that obtains approximate solutions to MAP that use no more than two classes. Examples are constructed using data extracted from the Official Airline Guide. Analysis of the examples suggests that fewer security classes for passenger screening may be more effective and that using passenger risk information can lead to more effective security screening strategies. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
544.
Although the Obama Administration has differed from its predecessor in a number of respects, on the specific issue of Ballistic Missile Defense (BMD), there is a striking continuity. The Obama Administration has remained committed to the BMD project, even as it has modified the schedule of deployments and prioritized different systems from the Bush Administration. Significantly, this has led to Chinese and Russian balancing in the nuclear sphere. As a result, there is evidence of a security dilemma-type dynamics in US relations with China and Russia. At present, there is no study that analyzes Russian and Chinese hard internal balancing against the USA in the sphere of missile defense during the Obama Administration. This article fills this gap.  相似文献   
545.
Due to expanding and increasing religious extremism and terrorism coupled with political instability in Pakistan, most western observers believe that Pakistan's nuclear weapons are not secure and could be taken over by terrorists. This would have adverse implications for the region and for global peace, especially for the security of USA and Europe. This article argues that this perception is based on a flawed understanding and knowledge of how Pakistan's command and control setup has evolved and operates. Pakistan's nuclear weapons are as safe as any other state's nuclear weapons. Pakistan has also been active in supporting and participating in global efforts to improve nuclear safety and security. Over the years, Pakistan has been quite open in sharing information regarding how it is improving its command and control system with western governments as well as scholars. This article argues that the steps Pakistan has taken to secure its nuclear weapons are adequate and that Pakistan would continue to further strengthen these measures; however, it is the expanding religious extremism, terrorism and anti-Americanism in the country which make the international perception of Pakistan extremely negative and then seep into the perception of Pakistan's nuclear weapons safety and security.  相似文献   
546.
US nuclear deterrence and arms control policy may be moving, by design and by inadvertence, toward a posture of strategic “defensivism”. Strategic “defensivism” emphasizes the overlapping and reinforcing impact of: (1) reductions in US, Russian and possibly other strategic nuclear forces, possibly down to the level of “minimum deterrence,” (2) deployment of improved strategic and/or theater antimissile defenses for the US, NATO allies and other partners; and (3) additional reliance on conventional military forces for some missions hitherto preferentially assigned to nuclear weapons. This article deals with the first two of these aspects only: the interaction between missile defenses and offensive force reductions in US–Russian strategy and policy. The findings are that stable deterrence as between the USA and Russia is possible at lower than New Strategic Arms Reduction Treaty levels, but reductions below 1000 deployed long-range weapons for each state, toward a true minimum deterrent posture, will require multilateral as opposed to bilateral coordination of arms limitations. Missile defenses might provide some denial capability against light attacks by states with small arsenals, but they still fall short of meaningful damage limitation as between powers capable of massive nuclear strikes.  相似文献   
547.
飞机再次出动保障活动所需时间长短对提升飞机的作战效能至关重要,针对当前在飞机保障资源有限约束条件下,再次出动保障活动工期最短难以实现的难题,提出了基于分支切割法的再次出动保障活动时间优化方法。该方法以飞机再次出动保障活动所需时间最短为目标,以有限的保障人员和保障作业间逻辑关系为约束条件,可计算出时间最短的飞机再次出动保障活动具体流程,并用VB6.0编制成计算机程序,开发了飞机再次出动保障活动分析系统。最后,对某型飞机真实保障活动进行了实例分析,结果表明,使用该方法计算得到的结果准确、可靠,与实际保障情况相符,可为飞机再次出动保障与决策提供指导,提升保障活动的自动化水平,具有很好的工程应用价值。  相似文献   
548.
为了增强支付系统的安全性和可靠性,设计了一种区块链技术下的智能支付系统.这个系统利用区块链的去中心化和分布式账本特性,提供了一种更加安全和透明的支付解决方案.系统将区块链技术、国密算法与支付系统相结合,给传统互联网支付系统提供一个更安全的保障.利用区块链技术的点对点特点,解决支付效率和数据安全等方面的问题.借助互联网大数据技术,对用户进行信用评级,提供信贷服务.结合跨链技术可以对不同区块链的数据进行共享,更好地解决资金流动性.相比比特币和以太坊等电子货币系统,该系统在安全性、交易吞吐率和交易时延等方面做到了权衡发展,使得各方面的性能有了一定程度的均衡提升,更能满足当前环境下的应用需要.  相似文献   
549.
众所周知,Vo IP技术在未来语音通信中所占的比重越来越大。随着Vo IP的不断发展,基于SIP协议的Vo IP应用也不断增多。但是,由于SIP协议高度依赖于开放的IP网络,使得其安全性逐渐成为关注和探讨的焦点。主要分析了SIP协议网络面临的一些安全威胁,包括典型的外部攻击技术和协议自身存在的漏洞等。探讨了为应对SIP安全威胁提出的加密、认证等安全策略并且分析了这些安全策略的优缺点,提出了针对SIP安全策略进一步改进的方向,旨在不断提高和完善基于SIP协议的安全性能。  相似文献   
550.
通过刚体飞行六自由度动力学方程建立弹射式导弹初始段无控飞行模型,并结合弹射装置动力模型和导弹发动机推力模型进行仿真计算。基于无控飞行模型和仿真结果分析了无人机配载弹射式导弹发射特性,在导弹初始飞行段对机弹分离安全性和导弹姿态控制要求进行了研究。对导弹不同静稳定度下的运动特性对比分析,分别给出了满足各种安全和控制要求的导弹静稳定度范围。进一步综合所有安全和姿态控制要求,得到了满足所有要求的最佳静稳定度。经过一个实例的仿真研究,结果表明建立的模型与所用到的方法是合理有效的。  相似文献   
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