排序方式： 共有32条查询结果，搜索用时 15 毫秒
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施云燕 《全球科技经济瞭望》2014,(2):41-47
为抢占新一轮发展的制高点,俄罗斯政府将航天产业列为优先发展的战略性新兴产业之一,加以重点扶持和发展。通过采用有效培养人才和吸引人才的政策和策略,例如,对人才培养进行长远规划,采用专业导向式的人才培养模式,着力改善人才队伍老龄化现状,提高薪酬待遇和改革分配制度等,俄罗斯航天产业科技人力资源的数量和质量都开始提升,对航天产业的发展发挥了重要的支撑作用,俄罗斯的航天产业逐渐呈现上升的发展趋势。 相似文献
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Human history demonstrates that the movement of men and information has always been of paramount importance. The size of communities is determined by the territory that is readily accessible by movement capability. Using a version of Darwinian ideas in the form of Lotka's equations of competition between species as an analogy, air transport and other elements of the transportation infrastructure are examined. It is found that they exhibit extreme dynamic stability over time at all hierarchical levels. 相似文献
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罗晖 《全球科技经济瞭望》2011,26(6):47-50
当前,全球面对金融危机和气候变化的双重挑战,需要各国的共同努力来建立一个新的全球经济、贸易和发展体系。对中国而言,资本市场对创新的忽视一直是使中国经济中的短板,是制约技术创新的瓶颈因素之一。中国发展绿色经济,既是实现科学发展的重要契机,也是实现大国崛起的重要契机。 相似文献
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Modelling futures term structures (price forward curves) is essential for commodity-related investments, portfolios, risk management, and capital budgeting decisions. This paper uses a novel strategy, wavelet thresholding, to de-noise futures price data prior to estimation in a state-space framework in order to improve model fit and prediction. Rather than de-noise the raw data, this method de-noises only wavelet coefficients linked to specific timescales, minimizing the amount of information that is accidentally removed. Our findings are that, for the first five futures maturities in our sample data, in-sample (tracking) and 5-day-ahead out-of-sample (forecasting) Root Mean Squared Errors (RMSEs) are smaller both (i) when we increase the number of factors from one to four, and (ii) when we de-noise the data using wavelet thresholding. The improvement due to wavelet thresholding is often greater than the improvement from adding one more factor to the model, which is important because going beyond four factors does not improve model fit. Wavelet-based de-noising thus has the potential to improve considerably the estimation of various economic time series models, helping practitioners and policymakers with better forecasting and risk management. 相似文献
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罗晖 《全球科技经济瞭望》2010,25(10):36-45
本文研究了美国近年来在基础科学领域取得的主要进展、国家科学政策动向以及前沿领域的研究重点,认为在生命科学、物质科学、能源科学、信息科学以及诸多交叉学科领域正孕育着革命性突破,美国政府为确保国家在科学领域的世界级领导地位,加大了联邦政府的资金投入。本文研究将为我国准确把握世界科学技术发展态势、整体部署前沿科学研究提供参考。 相似文献
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罗晖 《全球科技经济瞭望》2011,26(12):39-41
工业化养殖是近半个世纪以来人类应对不断增长的人口压力和提高农业劳动生产率所选择的一种路径。联合国的相关报告认为,恰恰是这些工业化养殖模式带来了更多的粮食安全风险,工厂化养殖不仅不能解决问题,反而会加剧粮荒和生态恶化,引发动物衍生疾病蔓延。中国应对工业化养殖带来的环境和社会问题进行严格调控,加快制定相关的法律法规、技术和管理规范,改造或新建养殖设施和污染处理设施。 相似文献
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Recent research provides considerable evidence that correlations between assets change significantly over time and diversification benefits of correlations may vary substantially based on the time-varying measure of correlation used for different asset types. Our study evaluates and compares alternative time-series correlation modeling techniques according to both statistical and economic metrics, focusing specifically on individual asset pairs. We identify the moving correlation structure that best tracks the dynamic conditional correlation estimates using a large set of different financial time series encompassing 467 asset pairs in nine different asset classes. Results from our direct, statistical loss function based, and indirect, portfolio mean-variance based, forecast evaluations provide optimal window-length ranges for 36 asset-class pairs which should help in portfolio construction as well as risk management. Furthermore for robustness tests, we implement the model confidence set approach which, without a benchmark specification, produces a set of models constructed to contain the best models with a given level of confidence among competing forecast evaluations. 相似文献
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Individualism and Momentum around the World 总被引：1，自引：0，他引：1
This paper examines how cultural differences influence the returns of momentum strategies. Cross-country cultural differences are measured with an individualism index developed by Hofstede (2001) , which is related to overconfidence and self-attribution bias. We find that individualism is positively associated with trading volume and volatility, as well as to the magnitude of momentum profits. Momentum profits are also positively related to analyst forecast dispersion, transaction costs, and the familiarity of the market to foreigners, and negatively related to firm size and volatility. However, the addition of these and other variables does not dampen the relation between individualism and momentum profits. 相似文献
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罗晖 《全球科技经济瞭望》2010,25(6):34-45
世界范围内创新格局正在深刻调整,美国科技界保持着强烈的忧患意识和进取精神。本文对美国国家科技政策和企业创新战略的研究发现,美国正致力于优化创新环境,鼓励市场竞争以推动创新和技术进步,政府以公共投资大规模投资创新,以应对科技进步日新月异带来的机遇和挑战。 相似文献