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201.
本研究旨在编制适合我国幼儿教师职业特点的心理资本问卷。在参考相关文献的基础上,根据访谈和开放式问卷调查,编制了问卷的项目;根据探索性因素分析,抽取了4个因素,即自信、乐观、希望和韧性。根据验证性因素分析和信效度分析,考察了问卷各项测量学指标,均达到要求。幼儿教师心理资本问卷共有21个项目,信度和效度良好,可以作为幼儿教师心理资本的测量工具。  相似文献   
202.
提出建立以军事技术创新为内在机制的新的军事发展模式,论述了这个发展模式的要点和特点以及为转向创新应注意解决的几个关键性问题.  相似文献   
203.
本文论述了世界军事在国际格局形成、发展、演变过程中的作用。军事实力是影响国际格局的重要因素,各国军事实力的变化,促使世界向多极化迈进;局部战争对国际格局具有直接作用,朝鲜、越南、阿富汗及海湾战争的爆发、进程与结果,影响着国际格局的发展;各国军事战略的对抗性和相溶性,亦同样对国际格局有重要影响。  相似文献   
204.
软件开发到底是一个什么过程?这个过程中的哪些工作能自动化?这是软件开发自动化的两个核心问题。本文以这两个问题为中心来展开讨论,试图提出一些见解以改进过去的研究工作。值得指出的是;基于这里的思想,我们已经实现了一个用于开发Ada 软件的支持系统。实验表明:在该系统的支持下,开发者能以最少的干预半自动地实现从问题的自然语言描述到程序包规范的转换。  相似文献   
205.
We address the problem of determining optimal ordering and pricing policies in a finite‐horizon newsvendor model with unobservable lost sales. The demand distribution is price‐dependent and involves unknown parameters. We consider both the cases of perishable and nonperishable inventory. A very general class of demand functions is studied in this paper. We derive the optimal ordering and pricing policies as unique functions of the stocking factor (which is a linear transformation of the safety factor). An important expression is obtained for the marginal expected value of information. As a consequence, we show when lost sales are unobservable, with perishable inventory the optimal stocking factor is always at least as large as the one given by the single‐period model; however, if inventory is nonperishable, this result holds only under a strong condition. This expression also helps to explain why the optimal stocking factor of a period may not increase with the length of the problem. We compare this behavior with that of a full information model. We further examine the implications of the results to the special cases when demand uncertainty is described by additive and multiplicative models. For the additive case, we show that if demand is censored, the optimal policy is to order more as well as charge higher retail prices when compared to the policies in the single‐period model and the full information model. We also compare the optimal and myopic policies for the additive and multiplicative models. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
206.
A fundamental contradiction has been built into America's intervention in Afghanistan since the first days of the war in 2001. On the one hand, US policymakers have viewed the promotion of liberal democracy, economic development, and strong centralized state institutions as essential to achieve victory over the long term. On the other hand, however, the US has relied on local warlords to win its battles against the Taliban from the first days of the intervention. The Obama administration's tortured policy review reflects the intractable dilemmas involved in trying to build a modern democratic state while relying on local warlords as crucial allies in the war against the Taliban.  相似文献   
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This paper offers the personal view of a senior executive in the Defence Procurement Agency about the future requirements of the defence industry’s principal UK customer. The focus here is on trying to identify the type of corporate behaviour and range of skill sets that the UK Government will need from defence suppliers, both primes and supply chain companies in the future. The concluding message from this ‘Customer View’ is that there is likely to be a continuing market for the company that specializes in delivering defence capability. It will be a company that will be looking for a long‐term relationship, with a specialist knowledge of its various national customers and a willingness to work openly and closely with them. It will be agile in its ability to bring together diverse technologies, to package them as a system and to deliver them either as hardware or as a service. Such suppliers will also need to innovate and to adapt at least as rapidly as the threats that they seek to counter.  相似文献   
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210.
随着公安警卫部队信息化建设的全面高速发展,云计算技术将更多地应用于警卫信息化建设。展望云计算在警卫信息化建设中的应用前景,分析当前警卫信息化建设中运用云计算技术所面临的问题及对策。  相似文献   
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