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101.
针对衰减-延迟欠定混合通信信号的盲分离问题,提出了一种基于子空间最小距离的源信号估计算法,通过计算观测信号到混合矩阵列矢量张成子空间的距离,估计任意时频点同时存在的源信号数目以及当前源信号对应的混合矩阵列矢量,把欠定混合问题转化为超定问题,然后通过计算Moore-Penrose逆矩阵求解源信号,理论分析和仿真结果验证了算法的有效性。 相似文献
102.
分析了基数滚动切块和层次分析-目标规划(AnalyticHierarchyProcessandGoalProgramming)投资分配模型的利弊,探讨了工程建设投资效能的估计方法,研究建立了基于效能分析的投资分配优化模型.该模型经实际算例分析证明,模型的思路清晰,便于理解和操作,具有较好的实用性. 相似文献
103.
郑亮 《兵团教育学院学报》2009,19(3):79-81,84
乐府是汉代文学的重要部分,对五言诗歌的成熟起了极为重要的作用。在古代文学的教学过程中,将汉乐府和先秦时期的诗经、楚辞进行比较,从思想内容、叙事艺术、人物形象等方面解读汉乐府中的名篇,可以让学生更好地理解掌握汉代文学的特点。 相似文献
104.
The article examines the findings of the Commission of Inquiry established by the Norwegian government in 2014 to evaluate all aspects of Norway’s civilian and military contribution to the international operation in Afghanistan from 2001 to 2014. Concerned with the wider implications of the Commission’s findings, it focuses on two issues in particular: (1) Norway’s relations with the US, a close and long-standing strategic ally whose resources, capabilities and dominance of decision-making dwarfed that of all other coalition partners in Afghanistan; and (2) Norway’s record in the province of Faryab, where, from 2005 to 2012, a Norwegian-led Provincial Reconstruction Team was charged with bringing security, good governance and development to the province. How Norway prioritised and managed relations with the US highlights and helps to problematise the challenges – political, practical and moral – facing small and medium-sized powers operating in a coalition alongside the US. Norwegian efforts in Faryab are revealing of the dilemmas and contradictions that plagued and, ultimately, fatally undermined the international intervention as a whole. As such, Norway’s experience provides a microcosm through which the inherent limitations of the attempt to transfer the structures of modern statehood and Western democracy to Afghanistan can be better understood. 相似文献
105.
李佳音 《中国人民武装警察部队学院学报》2008,24(5):81-83
军队思想政治教育要适应和谐社会的要求,一方面深化调节,注重满足军人自身发展的需要,引导官兵建立与和谐社会相融合的人际关系;另一方面,运用“和”的思想解决矛盾和问题,达到对官兵负面思想的有效控制。 相似文献
106.
Today, many products are designed and manufactured to function for a long period of time before they fail. Determining product reliability is a great challenge to manufacturers of highly reliable products with only a relatively short period of time available for internal life testing. In particular, it may be difficult to determine optimal burn‐in parameters and characterize the residual life distribution. A promising alternative is to use data on a quality characteristic (QC) whose degradation over time can be related to product failure. Typically, product failure corresponds to the first passage time of the degradation path beyond a critical value. If degradation paths can be modeled properly, one can predict failure time and determine the life distribution without actually observing failures. In this paper, we first use a Wiener process to describe the continuous degradation path of the quality characteristic of the product. A Wiener process allows nonconstant variance and nonzero correlation among data collected at different time points. We propose a decision rule for classifying a unit as normal or weak, and give an economic model for determining the optimal termination time and other parameters of a burn‐in test. Next, we propose a method for assessing the product's lifetime distribution of the passed units. The proposed methodologies are all based only on the product's initial observed degradation data. Finally, an example of an electronic product, namely contact image scanner (CIS), is used to illustrate the proposed procedure. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003 相似文献
107.
Iis Gindarsah 《Defense & Security Analysis》2016,32(4):336-353
With the rapid pace of regional arms modernization and unresolved territorial disputes, Indonesia is increasingly susceptible to the impact of emerging great power rivalry in Asia-Pacific. Rather than pursuing a robust military build-up, Indonesian policy-makers assert that diplomacy is the country’s first line of defense. This article argues that defense diplomacy serves two agenda of Indonesia’s hedging strategy – strategic engagement and military modernization. This way, Indonesian defense and security officials seek to moderate the impact of geopolitical changes while maintaining the country’s defensive ability against regional uncertainties. 相似文献
108.
109.
毕京京 《军队政工理论研究》2008,9(1):1-5
党的十七大鲜明确立了中国特色社会主义旗帜的指导地位。中国特色社会主义旗帜,是马克思主义真理观和价值观相统一的旗帜;其精神实质,是坚持科学社会主义基本原则与根据我国实际和时代特征赋予其鲜明中国特色的有机统一;其实践形态,是中国特色社会主义道路;其理论形态,是中国特色社会主义理论体系。高举中国特色社会主义伟大旗帜,就需要倍加珍惜、长期坚持和不断发展这条道路和理论体系。 相似文献
110.
Burn‐in is a technique to enhance reliability by eliminating weak items from a population of items having heterogeneous lifetimes. System burn‐in can improve system reliability, but the conditions for system burn‐in to be performed after component burn‐in remain a little understood mathematical challenge. To derive such conditions, we first introduce a general model of heterogeneous system lifetimes, in which the component burn‐in information and assembly problems are related to the prediction of system burn‐in. Many existing system burn‐in models become special cases and two important results are identified. First, heterogeneous system lifetimes can be understood naturally as a consequence of heterogeneous component lifetimes and heterogeneous assembly quality. Second, system burn‐in is effective if assembly quality variation in the components and connections which are arranged in series is greater than a threshold, where the threshold depends on the system structure and component failure rates. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 364–380, 2003. 相似文献