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排序方式: 共有1071条查询结果,搜索用时 15 毫秒
941.
942.
针对双经纬仪异面交会中目标点并不一定正好在公垂线上的问题,提出了在公垂线附近的空间区域上估计目标点位置的方法。该空间区域为以公垂线为对角线,各边分别平行于双经纬仪测量坐标系三轴的长方体空间区域。在目标点位置估计时考虑到经纬仪高低角与水平角测角精度的不同,以及目标点与经纬仪之间距离对空间点坐标精度的影响。采用蒙特卡洛方法模拟结果表明:新方法的目标点空间位置估计精度不亚于传统公垂线法,在特定情况下甚至能提高5%以上。模拟结果验证了新方法的可行性和有效性。 相似文献
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945.
国防科技评价是国家科技评价的组成部分,是国防科技管理的重要内容,是构建军民融合创新体系的内在要求。分析了国防科技评价的基本内涵,阐述了构建国防科技评价体系的总体设想,提出了改革国防科技评价制度的几点思考。研究认为,改革国防科技评价制度,完善国防科技评价体,要加强国防科技评价理论研究,重视国防科技评价机构建设,充分发挥第三方评价的作用,建立多元化的国防科技评价体系,完善国防科技专家选择机制,建立健全国防科技评价指标,加快国防科技评价人才培养,优化国防科技评价环境建设。 相似文献
946.
Matthew Crosston 《Defense & Security Analysis》2017,33(2):94-105
This work is about how the United States military has become dependent on networked technology. As arguably the largest contributor to national security, it has become so dependent that its chief doctrine integrates networked technology into nearly every specialty, with particularly intense focus on Network Centric Warfare. As the military’s old guard is replaced by the highly technical Millenial Generation, there is cause to pause when assuming this techno-acuity brings nothing but advantage and success. Vulnerabilities stemming from such extensive dependence offer opportunities for exploitation that have not gone unnoticed. The first step to moving forward from this point is to fully understand the extent to which the military has become dependent on computer networks. It might be the Millenials’ war today, but it would be quite unwise for the United States military to think about it and fight it in a purely Millenial way. 相似文献
947.
Raul Gouvea 《Defense & Security Analysis》2017,33(3):223-241
Recent elections in Latin America, such as those of Mauricio Macri in Argentina, Horacio Cartes in Paraguay, and the impeachment process of Dilma Rousseff in Brazil, point to a new direction in Latin American politics and away from the “hard left;” they also point to a new momentum in the security relationship between the US and Latin American countries. Former US President Obama’s 2016 trip to Cuba and Argentina was a clear demonstration of this new security paradigm and also a clear indication that there is a new momentum brewing in the US towards a rethinking and reshaping of security strategies and mindsets. This article will explore the multidimensional security relationship between the US and Latin American countries in light of recent changes in the US’ posture toward the region. 相似文献
948.
Mark Erbel 《Defence Studies》2017,17(2):135-155
This article reappraises the two most-studied country cases of military outsourcing: the USA and the UK. It argues that the contemporary wave of military contracting stretches back to the beginning of the cold war and not only to the demobilisation of armies in the 1990s or the neoliberal reforms introduced since the 1980s. It traces the political, technological and ideational developments that laid the groundwork for these reforms and practices since the early cold war and account for its endurance today. Importantly, it argues that a persistent gap between strategic objectives and resources, i.e. the challenge to reconcile ends and means, is an underlying driver of military contracting in both countries. Contemporary contracting is thus most closely tied to military support functions in support of wider foreign and defence political objectives. Security services in either state may not have been outsourced so swiftly, if at all, without decades of experience in outsourcing military logistics functions and the resultant vehicles, processes and familiarities with public-private partnerships. The article thus provides a wider and deeper understanding of the drivers of contractualisation, thereby improving our understanding of both its historical trajectory and the determinants of its present and potential futures. 相似文献
949.
Philip Adémọ́lá Ọláyọkù 《African Security Review》2017,26(4):378-398
Postmodern contradictions in postcolonial Nigeria have led to the fetishisation of alternative local security measures often labelled as vigilante activities. The profiling of these groups as ethnic militia often undermines their essential bid to provide security while delimiting security needs to the physical. The fallouts of such profiling are frictions between federal security agents and ethnic-based security groups, often resulting in violence, as exemplified by the 7 May 2013 incident between the Nigerian federal security agents and the Ombatse. This study focuses on the emergence and activities of the Ombatse as an alternative security apparatus of the Eggon. It presents three years of field research which entailed the use of ethnography, key informant interviews and observation. The findings reveal that the Ombatse emerged to assert historical legitimacy for both the physical and spiritual securitisation of the Eggon through a return to the ancestral ways of social engineering. The study considers the security challenges in Nigeria, and also situates the Eggon historical context within political, religious, sociocultural and economic intersections of securitisation. It concludes that the Ombatse situates its legitimacy within the Eggon past and retains its relevance through the holistic focus of providing both physical and spiritual security. 相似文献
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