"标记"(Hallmark)是美国国防高级研究计划局(Defense Advanced Research Projects Agency,DARPA)正在开展的一个项目,旨在突破一系列太空指挥控制的关键技术,为美国高级领导层提供实时理解与评估太空态势的工具.介绍了DARPA研..."标记"(Hallmark)是美国国防高级研究计划局(Defense Advanced Research Projects Agency,DARPA)正在开展的一个项目,旨在突破一系列太空指挥控制的关键技术,为美国高级领导层提供实时理解与评估太空态势的工具.介绍了DARPA研究Hallmark项目的背景和目标,归纳了工具与能力开发、试验床开发与集成以及验证评估等技术领域的核心内容和进展情况,针对太空作战指挥与控制提出了5点启示.展开更多
The global economic downturn caused primarily by the US sub-prime mortgage crisis in 2007 engendered revenue loss of the multinational corporations. Existing studies have yet to depict the detrimental impacts on city...The global economic downturn caused primarily by the US sub-prime mortgage crisis in 2007 engendered revenue loss of the multinational corporations. Existing studies have yet to depict the detrimental impacts on city＇s command and control functions induced by the sub-prime mortgage crisis together with its residual wave of global economic recession on the global spatial economy. Recent and previous studies have produced an ＇instant history＇ of the global spatial economy before the global economic downturn undermines the global economy in late 2008. How- ever, the waxes and wanes of major cities＇ command and control functions on the global economic arena before and after the outbreak of financial crisis and its associated geo-economic transitions are still poorly understood. This paper attempts to contribute a new set of customized data to update and fill in the gap in the literature with the investigation of the command and control functions of cities arotmd the world from 2005 to 2009. Particular attentions are paid to the time-space relationship of the geo-economic transition that can capture the recent historical images of the com- mand and control situation of different cities in the world.展开更多
The existing theory and techniques of wireless communication anti-jamming have reached their performance limit recently.With this focus,by leveraging the inherent characteristics of wireless communication and referrin...The existing theory and techniques of wireless communication anti-jamming have reached their performance limit recently.With this focus,by leveraging the inherent characteristics of wireless communication and referring to the principle of cyberspace endogenous security,this paper investigates the core issues of endogenous security in the electromagnetic space,namely,endogenous anti-jamming(EAJ),which can defend against unknown electromagnetic attacks effectively.Specifically,the subspace method is first adopted to establish the unified framework for the conventional spread-spectrum,intelligent,and endogenous antijamming,in which both the intrinsic development law of each technique and the internal logic between them are revealed.Then,the fundamental concept,key techniques,and development suggestions of wireless communication“N+1 dimensionality”endogenous anti-jamming are proposed to seek a disruptive breakthrough.展开更多
文摘"标记"(Hallmark)是美国国防高级研究计划局(Defense Advanced Research Projects Agency,DARPA)正在开展的一个项目,旨在突破一系列太空指挥控制的关键技术,为美国高级领导层提供实时理解与评估太空态势的工具.介绍了DARPA研究Hallmark项目的背景和目标,归纳了工具与能力开发、试验床开发与集成以及验证评估等技术领域的核心内容和进展情况,针对太空作战指挥与控制提出了5点启示.
基金Foundation item:Under the auspices of Hui Oi Chow Trust Fund(No.200902172004)Mrs.Li Ka Shing Fund,Strategic Research Theme on Contemporary China,Small Project Funding provided by the University of Hong Kong(No.200807176152)
文摘The global economic downturn caused primarily by the US sub-prime mortgage crisis in 2007 engendered revenue loss of the multinational corporations. Existing studies have yet to depict the detrimental impacts on city＇s command and control functions induced by the sub-prime mortgage crisis together with its residual wave of global economic recession on the global spatial economy. Recent and previous studies have produced an ＇instant history＇ of the global spatial economy before the global economic downturn undermines the global economy in late 2008. How- ever, the waxes and wanes of major cities＇ command and control functions on the global economic arena before and after the outbreak of financial crisis and its associated geo-economic transitions are still poorly understood. This paper attempts to contribute a new set of customized data to update and fill in the gap in the literature with the investigation of the command and control functions of cities arotmd the world from 2005 to 2009. Particular attentions are paid to the time-space relationship of the geo-economic transition that can capture the recent historical images of the com- mand and control situation of different cities in the world.
文摘The existing theory and techniques of wireless communication anti-jamming have reached their performance limit recently.With this focus,by leveraging the inherent characteristics of wireless communication and referring to the principle of cyberspace endogenous security,this paper investigates the core issues of endogenous security in the electromagnetic space,namely,endogenous anti-jamming(EAJ),which can defend against unknown electromagnetic attacks effectively.Specifically,the subspace method is first adopted to establish the unified framework for the conventional spread-spectrum,intelligent,and endogenous antijamming,in which both the intrinsic development law of each technique and the internal logic between them are revealed.Then,the fundamental concept,key techniques,and development suggestions of wireless communication“N+1 dimensionality”endogenous anti-jamming are proposed to seek a disruptive breakthrough.
