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排序方式: 共有158条查询结果,搜索用时 15 毫秒
101.
新型农村合作医疗制度是一项旨在改善中国农民医疗问题的社会政策。农民参与机制是新型农村合作医疗制度可持续发展的重要条件,参与范围是农民参与机制的基本要素之一。在新型农村合作医疗制度的运行过程中,农民具有广阔的参与空间,可以在政策制定、政策执行、政策评价和政策监督四个环节中充分发挥作用。  相似文献   
102.
从宏观经济层面、货币政策本身和金融体系内的微观因素分析了我国货币政策效果弱化的原因。指出金融抑制、外汇占款、货币政策传导机制不畅、中央银行缺乏独立性是弱化我国货币政策效果的主要因素。针对存在的问题,提出了加快疏通货币政策传导机制,改进和完善中央银行再贴现政策,大力发展债券市场,深化国有商业银行改革,注重资本市场和货币市场协调发展等对策建议。  相似文献   
103.
Innovation is fundamental to a space agency's mission. Yet, the industry's current dominant approach to new technology development – concerted investment in step-changes in capabilities to support a particular application – contradicts the conventional wisdom of innovation theory. In order to understand why, this paper uses a unique empirical case study, in which exogenous historical circumstances created unexpected additional opportunities for technology investment, to explore the merits of this approach. The value of follow-on periods of R&D is assessed in terms of simple marginal returns, implications for workforce dynamics and the interaction of mission sequencing and technology strategy. The analysis reveals an important contingency between mission paradigm and the value of follow-on investment. Specifically, while marginal performance improvements can be achieved at lower costs, their value depends on the availability of an appropriate mission opportunity. In the current paradigm, the risk of obsolescence is high compared to the potential benefit. However, if a new small mission, frequent flights, paradigm were to take hold, there may be great value in refocusing R&D strategy on later round improvements.  相似文献   
104.
本文讨论在存在仑容与资金约束的条件下,如何确定多项物品联合订购的近优库存控制策略。根据本文所建立的决策模型开发了计算机软件,并给出了例题求解结果。  相似文献   
105.
This article examines the long-term ‘Star Wars’ R&D programme initiated by President Reagan - the Strategic Defense Initiative (SDI). The nature of this initiative and the research programme that has been approved are described. There is still considerable uncertainty over where the SDI research will eventually lead - whether it be a limited BMD system designed to protect military targets or a comprehensive shield to protect the USA and its allies. The feasibility and potential implications of the SDI are examined with this caveat in mind.  相似文献   
106.
When the requisite technology exists, the US political process will inevitably include lunar surface activities as a major space objective. This article examines a manned lunar base in terms of three distinct functions: the scientific investigation of the Moon and its environment; development of the capability to use lunar resources for beneficial purposes throughout the Earth-Moon systems; and conduct of R&D leading to a self-sufficient and self-supporting manned lunar base. Three scenarios are outlined with respect to each possible function.  相似文献   
107.
Many of the problems that the Space Shuttle programme has had in meeting its goals of routine and cost-effective access to space can be traced to various characteristics of the decision to develop the Space Shuttle. That decision was made through a process of bureaucratic politics, with little attention given to future users of the Shuttle. The design chosen for development was a poor compromise between demanding Pentagon and NASA requirements and a limited budget.  相似文献   
108.
Sibing He 《Space Policy》2003,19(3):183-189
This article discusses China's ambitions in space now that it seems set to pursue human spaceflight. It suggests that, after sending its astronauts into space, completing orbital rendezvous-docking operations and placing a space lab in orbit, China will focus on the Moon with its Chang’e project. As an emerging space power, China will play a more active role in the international space community through collaboration in areas such as lunar exploration, science operations on the International Space Station, the Galileo Global Navigation Satellite System and the International Geosphere–Biosphere Program (IGBP). In particular, China will vigorously explore new opportunities to expand its cooperation with Russia and ESA to counteract Washington's attempt at containment. Meanwhile, Beijing will continue to follow its self-reliance principle to go its own way in space.  相似文献   
109.
中国积极财政政策评析   总被引:5,自引:0,他引:5  
文章从凯恩思理论出发,评价了积极财政政策的效果及其带来的财政风险,认为由于我国的利率非市场化和高储蓄倾向,积极财政政策并未产生挤出效应,但在一定程度上增加了国家的财政风险.考虑到国债投资收益的边际效用递减和民间投资的逐渐复苏,积极财政政策会逐步淡出.  相似文献   
110.
近年来,深度强化学习在解决序列决策问题上取得了很大进展,无模型强化学习算法在与环境不断交互的过程中学习策略,不需要提前对环境建模,使其适用于许多问题。针对以往使用强化学习进行末制导策略学习的训练不稳定问题,使用信任域策略优化算法直接学习末制导控制量,同时设计了一种新颖的奖励函数,可以提高训练稳定性和算法性能。在二维环境下进行了实验,结果表明,该算法具有良好的训练稳定性,并可以达到很好的命中效果。  相似文献   
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