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中小型企业集群及技术创新的正相关性分析 被引量:1
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作者 王旭林 《中国证券期货》 2011年第12X期132-132,共1页
企业的集群发展是世界范围的一种重要经济现象,创新则是中小企业集群保持竞争优势的有力支撑。在对集群与创新关系相关研究文献回顾的基础上,剖析了中小企业集群式创新的理论内涵,研究集群与技术创新的正相关性。
关键词 企业集群 技术创新 正相关性分析
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国企改革对市场机制的正相关性影响
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作者 谭运进 《商业时代》 北大核心 2004年第21期29-29,24,共2页
深化国有企业改革是提高国企效率,增强国企竞争力,杜绝国有资产流失,完善社会主义市场经济体制的迫切需要。
关键词 国有企业 市场机制 中国 国有资产管理体制 正相关性分析 改革 法人治理结构 经济效益
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Characteristics of soil enzymes and the dominant species of repair trees in the reclamation of coal mine area 被引量:1
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作者 Wen-Ying ZHANG Duo-Xi YAO +3 位作者 Zhi-Guo ZHANG Qing YANG Kui ZHAO Shi-Kai AN 《Journal of Coal Science & Engineering(China)》 2013年第2期256-261,共6页
In order to study the soil enzyme content at the mine reclamation area and choose a tree species with superior restoration capabilities, this paper takes Huainan Datong Mine as the study area, and five different enzym... In order to study the soil enzyme content at the mine reclamation area and choose a tree species with superior restoration capabilities, this paper takes Huainan Datong Mine as the study area, and five different enzymes under nine tree species as the study subject. The different enzyme activity indexes were measured, and the correlation analysis and the principal component analysis (PCA) method were applied to evaluate and screen the tree species with advanced restoration. The results demonstrate that there are some correlations among the different soil enzymes, including some very significant positive correlations among urease, phosphatase, invertase and protease. The best species in terms of repair is privet, and the worst is Haltong. This study provides a scientific basis for the selection of restoration-capable tree species in the reclamation area of the coal mine. 展开更多
关键词 reclamation area coal mine soil enzyme correlation analysis principal component analysis
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Radon Gas Measurements through Geiger and Sodium Iodide Scintillator——Study Efficiency Comparison
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作者 Inacio Malmonge Martin Marcelo Pego Gomes 《Journal of Environmental Science and Engineering(A)》 2017年第5期270-275,共6页
With the use ofa Geiger proportional counter with sensor tube of Russian and Chinese origin, a comparison was made in this work between measurements of environmental ionizing radiation with these detectors and a sodiu... With the use ofa Geiger proportional counter with sensor tube of Russian and Chinese origin, a comparison was made in this work between measurements of environmental ionizing radiation with these detectors and a sodium iodide scintillator activated with TI (Thallium NaI). Through measurements carried out in a room located inside a tower 25 meters high on the ITA (Technological Institute of Aeronautics) campus, it was possible to study the efficiency of the three instruments for the environmental measurement of ionizing radiations at that location. Between March 7th and June 2nd of 2017, in that region, nine intense and weak rains were observed with 12 cold fronts coming from southern Brazil. Radiation measurements and the local meteorology involved are analyzed in this work to verify possible correlations. 展开更多
关键词 Ionizing radiation RAIN radon gas.
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