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171.
我国环境管制、自主创新与FDI内含技术水平提升 总被引:3,自引:1,他引:2
吴磊 《中国人口.资源与环境》2010,20(3)
环境管制与技术创新对FDI内含技术水平的提升有着重大的影响。本文在对相关文献回顾的基础上,构建了一个包含环境管制与自主创新的分析模型,并利用近几年的数据实证检验了其对外商投资企业内含技术水平的影响。研究发现,我国的环境管制措施对外商投资企业内含技术水平的提高起到了显著的作用,而现阶段我国总体的自主创新能力对其影响则不明显;但是技术含量多、创新层次高的创新活动,对外商投资企业内含技术水平提升的促进效果十分显著。该研究结果具有重要的政策意义,即环境保护、自主创新与引进高技术含量的外资之间具有良性的互动效应。我国应该逐步提高环境管制水平,激励外商投资企业的技术创新和引进;进一步加强对技术含量高、具备核心竞争能力的创新活动的支持力度,实现环境效益提高与外资内含技术水平提升的均衡发展。 相似文献
172.
James C. Schneider David P. Ahlfeld Charles P. Spalding 《Journal of the American Water Resources Association》2017,53(3):697-706
A method is proposed for the equitable allocation of impacts of groundwater pumping on streamflow. The method is intended for cases in which the pumping activity of multiple entities has impacts on streamflow and these impacts are computed by perturbation. It is shown that when the response of streamflow to pumping is nonlinear, simple methods for impact calculation can fail. The proposed method is developed for the case when there are four entities that impact streamflow. The method relies on the calculation of impacts by perturbation of the simulation model from different base pumping levels. When four entities are evaluated, 16 runs of the simulation model are required. It is shown the proposed method produces estimated impacts for each individual entity that are equitable because they meet the requirement that the impacts of each entity sum to the total impacts of all entities acting together and the impacts attributed to each entity do not depend on the order of calculation. A brief example demonstrates the approach. 相似文献
173.
Evaluating Links Between Forest Harvest and Stream Temperature Threshold Exceedances: The Value of Spatial and Temporal Data 下载免费PDF全文
Jeremiah D. Groom Sherri L. Johnson Joshua D. Seeds George G. Ice 《Journal of the American Water Resources Association》2017,53(4):761-773
We present the results of a replicated before‐after‐control‐impact study on 33 streams to test the effectiveness of riparian rules for private and State forests at meeting temperature criteria in streams in western Oregon. Many states have established regulatory temperature thresholds, referred to as numeric criteria, to protect cold‐water fishes such as salmon and trout. We examined across‐year and within‐year patterns of exceedance at control and treatment stream temperature probes. Determining whether an exceedance at the downstream end of a harvest was unambiguously related to harvest proved surprisingly difficult. The likelihood of a site exceeding its numeric criterion appeared related, in part, to the site's preharvest temperature range. Four control reaches as well as three preharvest treatment reaches exceeded their numeric criteria, necessitating additional analysis to evaluate timber harvest impacts. Nine percent of sites (3 of 33) both exceeded their numeric criteria and exhibited a potential harvest effect (16.7% of private sites [3 of 18], 0% of State sites [0 of 15]). After harvest, exceedances were typically observed in only the first of the two post‐harvest years. These findings highlight the importance of including temporal and spatial controls in temperature assessments of numeric criteria when the assessment's purpose is to determine whether exceedances are related to human activities. 相似文献
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175.
Thomas L. Traynor 《Journal of Safety Research》2009,40(6):421-426