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691.
师玉朋  刘海林 《国防科技》2018,39(6):066-071
发展军民融合产业是各级政府落实军民融合发展国家战略的重要抓手之一。针对军民融合产业界定不清等问题,从理论研究和实践工作层面梳理既有观点及演变趋势,形成对军民融合产业的客观认识。在此基础上,剖析军民融合产业的属性特征,从指导实践工作角度出发提出三种界定军民融合产业范畴及相关统计工作的合理化思路,并提出建立两级联动工作机制、开展国家工业基础中国防科研生产能力普查工作、试点开展军民融合产业分类标准及指标体系建设工作、加强军民融合产业统计数据质量监测等政策建议。  相似文献   
692.
赵云  陈磊  张博 《国防科技》2018,39(5):048-052
国防科技能够为"一带一路"沿线国家的经济、政治、安全、科技、文明等方面的发展进步做出重要贡献,我国可以将核能、航空、航天、船舶等国防科技领域作为重点先导领域推进实施。要着眼面临的机遇与挑战,着重从促进战略对接、打造品牌优势、推进军民融合、加强人才培养和关注人文交流等方面搞好战略应对。  相似文献   
693.
This article is the latest in a series of published articles systematically examining Afghan Presidential and legislative elections. Structural problems including fraud, ethno-linguistic block voting, and the Single Non-Transferable Vote have had significant impacts on the development of Afghan democratic elections. The challenge now facing the current Afghan government and future elections is the daunting task of uniting the Afghan people while not repeating the electoral mistakes of the past. The tricky balancing act of fostering an overarching national identity without being perceived as privileging particular identities requires strong leadership and a willingness to challenge traditional ethnic, linguistic, and religious norms when need be. Karzai and Ghani Administrations have seriously failed relative to this dynamic.  相似文献   
694.
In the context of restricted budgetary resources and the growing cost of maintenance, repair, and overhaul (MRO) activities, a major issue for modern armed forces is to sustain defense platforms. A possible method consists of realizing economies of scale through the concentration of maintenance activities, which involves the spatial reorganization of existing industrial sites dedicated to MRO. This article provides a formalized framework to discuss the optimal organization for the MRO of defense platforms in space. The public planner organizes the maintenance of defense platforms with only two possible spatial configurations. In the dispersed configuration, two industrial production units in charge of the maintenance optimally cover space, whereas in the concentrated configuration, a unique industrial unit covers space. Focusing on the tipping point between the two configurations, the balance of forces between agglomeration and dispersion in defense support activities is described and discussed. On the one hand, economies of scale provide an opportunity to optimize defense support costs, favoring concentration in a unique industrial unit. On the other hand, space causes dispersion to reduce both transport costs and operational social costs. This trade-off illustrates a general principle in spatial economics with an application to MRO production in the French case.  相似文献   
695.
International concern over nuclear terrorism has grown during the past few decades. This has driven a broad spectrum of efforts to strengthen nuclear security globally, including the widespread adoption of radiation-detection technology for border monitoring. Detection systems are now deployed at strategic locations for the purported purpose of detecting and deterring the smuggling of nuclear and radioactive materials. However, despite considerable investment in this area, few studies have examined how these programs are implemented or the operational challenges they face on a day-to-day basis. This article seeks to address this with a focus on radiation-detection efforts at maritime facilities. Utilizing practitioner interviews and a survey, this article identifies the factors that influence the planning and use of these systems in this fast-moving environment. The results clearly demonstrate that the implementation of these systems varies significantly across different national and organizational contexts, resulting in a fragmented global nuclear-detection architecture, which arguably undermines efforts to detect trafficked nuclear-threat materials. Greater consideration should therefore be given to developing international standards and guidance, designing and adopting tools to support key parts of the alarm assessment process, and broader sharing of good practice.  相似文献   
696.
Between 2014 and 2017, no less than 10 different non-governmental organizations (NGOs) conducted maritime Search and Rescue (SAR) operations off the coast of Libya. By rescuing over 100,000 migrants in three years, these NGOs became the largest provider of SAR in the Mediterranean. The theory of institutionalism suggests that organizations conducting similar activities are likely to converge in a process of mimetic isomorphism, deliberately imitating one another to increase their effectiveness and cope with uncertainty. These 10 SAR NGOs, however, developed two different rescue models: While some rescued migrants and disembarked them in Italian ports, others only simply assisted those in distress until the arrival of another ship transporting them to land. They also cooperated with Italian and European authorities to different degrees. Why did SAR NGOs imitated many elements of existing non-governmental rescue models, but discarded some others? This article argues that differences in material capabilities and organizational role conceptions are crucial to explain why newer SAR NGOs have imitated most but not all of their predecessors’ policies, engaging in a process of “selective emulation.”  相似文献   
697.
This study applies a non-parametric causality-in-quantiles test to examine the causal effect of geopolitical risks on return and volatility dynamics of Islamic equity and bond markets. Geopolitical risks are generally found to impact Islamic equity market volatility measures, rather than returns. However, geopolitical risks tend to predict both returns and volatility measures of Islamic bonds. Interestingly, causality, when it exists for returns and/or volatility of Islamic equities and bonds, is found to hold over entire conditional distributions of returns and volatilities, barring the extreme ends of the same.  相似文献   
698.
随着现代化导航信号带宽的增大,由于可以大幅降低采样率,复信号采样的优势日趋明显。由于存在I/Q幅相误差,复信号采样对导航接收机伪距测量造成了一定影响。改进了信道非理想与I/Q幅相误差共同影响BPSK/QPSK信号零值测量的分析模型;在该模型基础上,推导得到了任意I/Q误差和信道非理想特性影响BOC信号伪距零值的模型;探讨了二者在频域抗干扰应用场景下引起的零值变化;理论分析与软件接收机仿真结果高度吻合,误差在1.5×10-4码片内,证明了分析模型的精确性。该分析方法可用于对高性能导航接收机信道特性进行事先约束及筛选,以确保干扰场景下的零值变化满足要求。  相似文献   
699.
针对指数寿命产品的定时、定数截尾试验方案,推广了Mazzuchi-Soyer模型的应用范围。首先引入模型假设,以狄氏分布作为先验分布,综合利用产品研制的历史信息和专家信息,结合产品研制各阶段试验数据,给出了各阶段可靠性的联合后验分布。然后利用Gibbs抽样算法解决后验推断计算问题,得到各阶段产品可靠性的Bayes点估计和区间估计。最后给出产品可靠性增长分析实例,表明了模型的优越性。  相似文献   
700.
在逐步Ⅰ型混合截尾试验下,研究了Burr部件寿命参数及可靠性指标的极大似然估计和Bayes估计.利用简单迭代方法,给出了寿命参数和可靠性指标的极大似然估计的数值解.然后利用Lindely Bayes近似算法得到了平方损失下寿命参数以及可靠性指标的Bayes估计.最后,运用Monte-Carlo方法对各估计结果作了模拟比较,结果表明Bayes估计较极大似然估计的误差小.  相似文献   
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