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551.
分析了电传操纵系统可靠性,介绍了可靠性设计的工程方法.建立了飞行员排除故障的数学模型,提出了确定驾驶员排除飞行危险的条件概率的两种方法;在研究人-机闭环系统基础之上,建立了基于马尔可夫链的飞行安全评估模型,提出了由于飞行控制系统故障引起飞行危险的安全评估计算方法.最后以横向通道传感器故障为例对某型飞机进行安全评估.  相似文献   
552.
西方治安管理主体多元化探析   总被引:2,自引:0,他引:2  
传统观念认为,政府警察机构是维护社会治安秩序的主体。然而,西方国家的治安管理实践表明,私人保安、社会自治组织等社会治安组织也参与社会治安管理工作,与警察机构合作、互动,共同维护社会秩序。治安管理主体呈现多元化的原因主要有三个方面:一是西方政府机制本身内在固有的缺陷导致警察机构治安服务失灵现象为其提供现实依据;二是新公共管理、自组织网络治理等理论为其产生提供理论基础;三是治安需求的多元化为其提供了发展的动力。  相似文献   
553.
在灭火救援中,尤其是在突发情况下,安全与灭火救援之间的关系值得研究。在对突发情况这一概念界定的基础上,分析了突发情况下安全与灭火救援的关系,从消防战术的角度提出了处理两者之间的关系问题,从消防技术的角度展望了两者的发展方向。  相似文献   
554.
大型活动期间消防安全保卫工作具有活动形式多样,安全问题被忽视;活动期间人员密集、流动量大;各种致灾因素增多,安全系数低等特点。基于此,作为消防机关部门和基层值勤单位应具有不同的工作重点,以确保大型活动期间消防安全保卫任务的完成。  相似文献   
555.
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   
556.
程桂龙 《国防科技》2013,(5):59-64,103
“空海一体战”是美国的一种新型作战理论,是在20世纪80年代“空地一体战”等诸多战法及兵种妥协基础上形成的一种新型军事战略,旨在通过空海军力量的配合,进行近域作战,以抵消对手的反进入/区域拒止能力,取得战争的主动权与控制权.“空海一体战”作为美国战略重心东移的重要角力点与支撑要素,在美国亚太战略中的作用举足轻重,对亚太周边国家尤其是中国的国家安全构成重大威胁,为此有必要对其理论渊源、发展目标、策略行动及障碍缺陷进行剖析与解构,为中国维护国家安全,构建良好的国家安全环境提供战略储备与智力支持.  相似文献   
557.
As US counterinsurgency campaigns draw to a close, doctrine for asymmetric warfare written during the War on Terror has come under heavy criticism. While many have argued that this shift to ‘winning hearts and minds’ is evidence that the United States is taking humanitarianism and nation-building seriously, others argue that a wide gap exists between US counterinsurgency doctrine and the protection of civilians afflicted by conflict. In this article, I show that the latter is true by comparing theories of instrumental and communicative action to US doctrine for operational design, stability operations, and counterinsurgency. I argue that these texts treat the people as an object to be manipulated for the achievement of pre-determined self-interested strategic goals rather than members of a community that jointly designs operations to fulfill shared objectives. However, US doctrine does contain communicative elements that, if prioritized, would better support humanitarian and state-building objectives otherwise subordinated in the War on Terror.  相似文献   
558.
ABSTRACT

This paper challenges recent claims that competitive market dynamics incentivize Private Military and Security Companies (PMSCs) to fully commit to providing effective services, thereby reducing the duration of civil war. Our assessment of a most-likely case scenario for this argument – Sierra Leone – reveals four critical problems. First, there is rarely direct competition, even if numerous companies are present. Second, the presence of multiple PMSCs usually represents a collaboration among subsidiaries providing distinct services, often under the same corporate umbrella. Third, data aggregation obfuscates the overlap of PMSC presence, inflating the amount of perceived competition. Finally, we raise concerns regarding how quantitative analyses can conflate conflict intensity with conflict termination.  相似文献   
559.
560.
SWAZILAND     
The election of Sheik Sharif Sheik Ahmed as the transitional president of Somalia was the climax of the United Nations (UN)-led Djibouti peace process. The election, it was hoped, would herald the beginning of the reconstitution of the Somalian state. Unfortunately, nearly three years after the event, that has still not happened. The government of Sheik Sharif has faced a number of challenges which are yet to be resolved. In the end, the Djibouti peace process has not guaranteed a stable and functional national government in Somalia.  相似文献   
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