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911.
依据复杂网络理论,建立了有限规模BA无标度网络模型来分析Ad Hoc网络,为进一步分析对其实施通信干扰的可行性打下结构基础。依据所建模型的拓扑结构,建立了通信干扰方程,探讨了通信干扰可能对Ad Hoc网络带来的影响。最后提出节点势能的概念,分析了通信干扰条件下Ad Hoc网络的效能,证实了实施通信干扰的实践可行性。  相似文献   
912.
基于反辐射导弹告警技术的原理,分析了反辐射导弹雷达告警技术和光电告警技术的可行性。定义了告警设备的抗电子摧毁因子,并给出了分析过程和计算模型。以命中概率为指标,对反辐射导弹告警技术的作战效能进行了分析研究。仿真得出反辐射导弹命中概率与告警设备告警距离、发现概率等参数的关系,可为反辐射导弹告警技术的研究提供一定的参考。  相似文献   
913.
目前,国内外对双旋翼直升机的微多普勒特性研究相对还很少。建立了直升机旋翼回波的微多普勒模型,并基于该模型,分别计算了共轴式、横列式、纵列式以及交叉式双旋翼直升机的微多普勒。研究结果表明,不同种类的双旋翼直升机旋翼的微多普勒特性不同,通过对双旋翼直升机旋翼的微多普勒进行分析,可以对双旋翼直升机进行初步分类,为下一步双旋翼直升机的微多普勒识别提供了参考和借鉴。  相似文献   
914.
对某无后端数据库RFID安全认证协议的安全性进行了分析,并针对其安全漏洞,给出了一种新型的无后端数据库的RFID安全认证协议。对新协议的安全性分析表明:该协议能够满足双向认证、匿名性、抗追踪攻击、抗克隆攻击、抗物理攻击、抗窃听、抗拒绝服务攻击以及失同步攻击等要求。最后,给出了新协议的BAN逻辑证明。  相似文献   
915.
This article examines Poland's national potential and its international position within the European Union (EU) with respect to security issues. It presents research results based on a comparison of Poland's national potential as it relates to other EU countries, which is useful when evaluating Poland's power within the EU. The article also evaluates Poland's crisis potential, i.e. it identifies those factors that may potentially be treated as threats to national and regional security. Finally, it enables the identification of challenges to Poland's security in the second decade of the twenty-first century. The research is conducted according to a multidimensional comparative analysis, which is perceived by the author as the best available to measure a country's power despite its weaknesses.  相似文献   
916.
This article explores gender and security sector reform (SSR) in Zimbabwe from 2008 to the present. It firstly postulates that the purpose of gender-sensitive SSR is to transform security services so as to enhance human security, as opposed to having an exclusive focus on state and territorial security. A comprehensive analysis of the policy and legislative framework governing gender and SSR at the global, continental, sub-regional and national levels will be presented, followed by the argument that efforts to reform the partisan and oftentimes non-professional tendencies of the security sector – especially the Zimbabwe Defence Forces, Zimbabwe Republic Police, Central Intelligence Organisation and Zimbabwe Prison Services – to promote democracy have met with firm resistance. However, gender-sensitive SSR has made significant headway in Zimbabwe since it is considered less threatening by the government. It should be noted, nevertheless, that gender-sensitive SSR has the potential to shift levels of professionalism and accountability within the sector as well as change attitudes to enhance security at the personal and communal levels. The process can gradually increase the percentage of women serving in the security sector. In conclusion, recommendations are made to broaden and deepen gender-sensitive SSR as the only viable alternative in the current political environment in Zimbabwe.  相似文献   
917.
Policy research and scholarship on food has rapidly increased in recent decades. The attention to ‘gender' within this work appears to signal important practical and academic efforts to mainstream gendered understandings of food consumption, distribution and production into expansive conceptualisations of human security. This article argues that the gender-related work on food has wide-ranging and often troubling political and theoretical foundations and implications. Often growing out of knowledge regimes for managing social crises and advancing neo-liberal solutions, much gender and food security work provides limited interventions into mainstream gender-blind work on the nexus of power struggles, food resources and globalisation. A careful analysis of knowledge production about gender and food is therefore crucial to understanding how and why feminist food studies often transcends and challenges dominant forms of scholarship and research on food security. This article's critical assessment of what food security studies in South Africa has entailed at the regional level and in global terms also focuses on the methodological and theoretical feminist interventions that can stimulate rigorous conceptual, research and practical attention to what has come to be understood as food sovereignty.  相似文献   
918.
建立了高超声速巡航飞行器机身/推进系统一体化设计模型,对高超声速巡航飞行器机体/推进系统设计参数对性能的影响进行了分析,提出了一种新的设计参数灵敏度分析方法和设计参数取值域界定方法,确定了各设计参数的影响等级并对设计参数取值域进行了划分。  相似文献   
919.
磁悬浮列车系统轨道动力学分析与试验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
本文建立了磁悬浮列车系统轨道动力学方程组,讨论了轨道结构参数对弹性轨变形、极限速度及模态的影响,并结合KDⅢ车的试验结果作出分析。  相似文献   
920.
本文利用振动信号实部与虚部之间Hilbert关系的原理,发展了它在模态试验中非线性检测技术。针对工程结构的特性采用了快速算法和修正技术,通过火箭风罩证明了它的实用性  相似文献   
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