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911.
基于小波神经网络的蒸汽发生器水位辨识与控制仿真   总被引:1,自引:0,他引:1  
提出一种基于小波神经网络的控制方法,对蒸汽发生器水位进行控制仿真.该方法利用小波神经网络作为控制系统的辨识器和控制器来构成控制系统.小波神经网络辨识器能更准确逼近非线性对象,小波神经网络控制器能自适应产生最佳的控制规律.仿真结果表明,该方案具有响应快、超调量小、较强抑制干扰能力等良好性能.  相似文献   
912.
设计安全策略模型时应考虑安全策略的时序特性和灰色特性,还应综合考虑保密性、完整性和可用性三方面的需求。已有的安全模型没有描述时序性和灰色特性,而且一般只侧重描述保密性或完整性。为此,本文提出了动态灰色时序系统(简称DGTS)。本文详细描述了DGTS,以及基于DGTS的动态语义设计的灰色时序安全策略规范语言GTSL。  相似文献   
913.
In his 2009 Prague speech and the 2010 Nuclear Posture Review, President Barack Obama committed the United States to take concrete steps toward nuclear disarmament while maintaining a safe, secure, and effective nuclear deterrent. There is an inherent tension between these two goals that is best addressed through improved integration of nuclear weapons objectives with nuclear arms control objectives. This article reviews historical examples of the interaction between the two sets of objectives, develops a framework for analyzing opportunities for future integration, and suggests specific ideas that could benefit the nuclear weapons enterprise as it undergoes transformation and that could make the future enterprise compatible with a variety of arms control futures.  相似文献   
914.
The efforts of President Barack Obama and his administration to restore the United States as a driving force of multilateral arms control and nonproliferation negotiations are commendable, yet the lack of progress on such issues over the last eight years has ensured that U.S. policy has not kept pace with changes in the geostrategic environment and the evolving security agenda. Meanwhile, an alternative agenda has been articulated by non-Western countries. This article focuses on the arms control perspectives of Non-Aligned Movement states and others that have begun to embrace the idea of “disarmament as humanitarian action.” It explores this idea in the context of recent initiatives and argues that if the Obama administration wants to make progress on its arms control and nonproliferation priorities, it should consider a multifaceted approach that incorporates this emerging alternative agenda.  相似文献   
915.
Notwithstanding the embrace of modern institutions of social control, traditional social control mechanisms still enjoy patronage in Nigeria. This paper examines the traditional structures of social control in Iraye-Oke, Lagos. In-depth interviews, key informant interviews and case studies were used to obtain data from participants. Findings established the functionality of traditional structures in checking crime and its preference over the use of modern social control structures. Traditional structures used include: traditional spiritualists who provide measures to reduce victimisation; the family courts where adjudication takes place involving elders and family chiefs; and the apex traditional court, presided over by the king, where cases like murder, land disputes, adultery and fornication are decided. Traditional extrajudicial measures involve the invocation of ancestral spirits at shrines.  相似文献   
916.
This article is about the management of security incidents in organisations and companies which are under the protection of private security personnel, whether in-house or contracted. Incidents can be defined as accidental or anecdotal (bird flies into a camera) to a violation of law or company policy. Managing security incidents is one of the key functions of a private security service provider. The purpose of this study is to explore the management of security incidents and the information related thereto, identify shortcomings and find solutions for managing these shortcomings. Interviews were used to gain insight from personnel within the private and government sectors which are served by the private security industry. It was found that security incidents are handled in a routine way by organisations from the different sectors. One major shortcoming is that security incidents and the information related thereto are not managed by security service providers according to an operational framework or model with the required infrastructure and resources. The significance of this study is for security incidents to be managed correctly, so that the information related thereto may be captured accurately, analysed and used proactively and reactively to improve physical protection systems, develop preventative strategies and provide actionable information products in order to reduce crime, increase detection rates and prevent losses.  相似文献   
917.
918.
ABSTRACT

An arms race in cyberspace is underway. US and Western government efforts to control this process have largely been limited to deterrence and norm development. This article examines an alternative policy option: arms control. To gauge whether arms-control models offer useful lessons for addressing cyber capabilities, this article compiles a new dataset of predominantly twentieth-century arms-control agreements. It also evaluates two case studies of negotiated agreements that regulate dual-use technologies, the 1928 Geneva Protocol prohibiting chemical- and biological-weapon use and the 1944 Chicago Convention on International Civil Aviation. The analysis underscores the limits of norm development for emerging technologies with both civilian and military applications. It finds lessons for developing verifiable, international cooperation mechanisms for cyberwarfare in the regulatory model of international aviation. Conventionally, arms-control agreements take advantage of transparent tests or estimates of arms. To restrict cyberwarfare activities, experts and policy makers must adapt arms-control models to a difficult-to-measure technology at an advanced stage of development and use. Further investigation of international regulatory schemes for dual-use technology of similar diffusion and development to the internet, such as international civil aviation, is needed.  相似文献   
919.
Since the July 2009 Boko Haram terrorist outburst in Nigeria, there have been increasing questions on the phenomenon in the country. There has not been any substantial analysis on the emergence of the Boko Haram group and its terrorist activities in Nigeria as the out-rage continues. This study is advanced to explain the phenomenon of Boko Haram terrorism in Nigeria. It employs the levels of analysis framework popular in the field of international relations to explain the terrorism at three major levels: individual, state and international. The study relies on dependable news reports, which include interviews with key actors relevant to the subject matter, and finds that Boko Haram terrorism has its roots in the ideology and motivations of its founder and members, the failures and deficiencies of the Nigerian state, and the modern trend of religious terrorism in the international system.  相似文献   
920.
The criticism of James, Solberg and Wolfson (JSW) (1999) by Oneal and Russett (OR) is not responsive to the methodologica] issues at stake. JSW argued that war is an endogenous feature of the world political and economic system. If its causes are to be measured, it must be as a structural equation in a simultaneous system. Wedded to the idea that “democracies never fight each other,” OR rely on a single equation to justify their view. JSW claim that such an equation may be an ad hoc reduced form with no causal implications unless the equation is explicitly identified as a structural equation. JSW expand the model to explain democracy and conflict as two endogenous variables. JSW do not claim to have discovered the true relationships between these variables by their minimal expansion of the structural relation. They do show that unless these (and other) variables are treated as part of a system, the results are unstable, contradictory, of minimal size and not a reliable guide to public policy.  相似文献   
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