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排序方式: 共有127条查询结果,搜索用时 15 毫秒
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Amadeo Watkins 《Defense & Security Analysis》2019,35(3):261-282
The possibility for Croatia to obtain new fighter aircraft is not new, as this option has been publicly debated for at least a decade. A sudden decision to advance the acquisition of a limited number of fighter aircraft was made in 2017 with an international tendering process concluding in early 2018. Through open source material, this paper will look at this procurement process by examining the relationship between policy and strategic thinking on the one side, and policy delivery on the other, and evaluate why the tendering process failed in achieving envisaged results. The paper concludes that the problems facing the Croatian aircraft acquisition process stem from at least two interrelated factors: firstly, at the operational level, the failure of the procurement was the direct result of mismanaged tendering procedures linked to the wider public administration reform process; and secondly, at the strategic level, inherently complex civil-military relations and related cultural aspects which have not been adequately addressed over the past decades. The result was a failure to deliver on government policy, something which this paper argues will need to be addressed over the medium to long term. 相似文献
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李蕾 《兵团教育学院学报》2009,19(6):53-55
第二语言习得的研究出现多元化现象,研究者从不同的角度、不同的侧面进行深入的研究,提出了许多新的观点。随着这一领域研究的深入,研究学习者外语学习的心理一认知过程逐渐成为第二语言习得领域学者关注的热点。本文认为学习者坚持语言学习不仅仅是习惯的养成,而是一种语言习得、脑力劳动和认知发展过程,强调学习者在语言学习过程中的积极作用,有利于促进第二语言的获得。 相似文献
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李蕾 《中国人民武装警察部队学院学报》2010,26(7):88-90
在信息化技术迅猛发展的背景下,如何利用网络资源加强学报建设与发展,成为编辑工作者普遍关注的问题之一。组稿和审稿在期刊编辑工作中具有举足轻重的作用。针对当前公安院校学报在组稿和审稿工作中存在的问题,提出利用网络资源解决问题的途径。 相似文献
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下一代全球导航卫星系统将采用数据和导频通道功率不等的调制方式,而传统算法多采用数据和导频通道的等权重加权联合进行捕获。当二者功率不相等时,等权重加权联合不能获得最优的捕获性能。因此提出功率加权联合的改进捕获算法,在数据和导频通道的功率分配不等的情况下,进行不同加权系数的联合捕获,并且利用最小二乘的方法进行最优加权系数的拟合估计。利用捕获判决量的特征函数推导检测和虚警概率。仿真实验验证了当数据和导频功率比为1∶3、检测概率为0.8、虚警概率为10-3时,所提出的改进算法能提升0.4 d B的捕获灵敏度。 相似文献
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This article investigates the impact of timing on sellers' information acquisition strategies in a duopoly setting. Market uncertainty is captured by a representative consumer who has a private taste for the product's horizontal attribute, and both sellers can acquire this information either before (ex‐ante acquisition) or after (ex‐post acquisition) observing their own product qualities. We identify several conflicting effects of information acquisition that vary significantly in its timing and market characteristics. In the monopoly scenario, information acquisition is unambiguously beneficial and ex‐ante acquisition is the dominant option, because it helps a seller not only design the proper product but also craft better pricing strategy. By contrast, when there is competition, information acquisition eliminates the buffer role of market uncertainty and leads to the fiercest production or pricing competition, which makes the subsequent effects of acquisition detrimental, and a seller's payoff is nonmonotonic in terms of its acquisition cost. Moreover, compared with the ex‐ante information acquisition, ex‐post information acquisition normally generates higher sellers' equilibrium payoffs by postponing the timing of acquisition and maintaining product differentiation. Nonetheless, ex‐post information acquisition also provides the seller with greater acquisition incentive and occasionally makes him worse off than that in the ex‐ante scenario. Thus, in a competitive environment, having the option of information acquisition and flexibility in its timing can be both detrimental and irresistible. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 3–22, 2016 相似文献
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装备采办各个阶段都存在着不确定的因素,为加强风险管理,重点研究了在武器装备采办过程中可能出现的13个风险区域,并对各个风险区域可能出现的风险源进行了较为详细的分析。同时详细研究了辨识风险的4种方法,即基于工作分解结构的风险辨识方法、基于项目评审的风险辨识方法、基于费用分析的风险辨识方法和基于试验与评价的风险辨识方法。 相似文献