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Technological Gap, Innovation Environment and Enterprises' Independent R&D Intensity
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作者 傅晓霞 吴利学 《China Economist》 2013年第2期56-69,共14页
关键词 技术 自主研发 差距 企业 环境 创新 生产函数
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A comparison of the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women:A randomized controlled trial
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作者 Tahereh BEHROUZI LAK Nader AGHAKHANI +5 位作者 Davoud VAHABZADEH Samereh EGHTEDAR Rozita CHERAGHI Nazafarin GHASEMZADEH Vahid ALINEJAD Maryam MESGARZADEH 《Journal of Integrative Nursing》 2023年第1期21-26,共6页
Objective:The aim of this study is to compare the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women who were referred to the Ko... Objective:The aim of this study is to compare the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women who were referred to the Kowsar gynecological clinics of Shahid Motahari Hospital of Urmia University of Medical Sciences.Materials and Methods:A double-blinded clinical trial was conducted on 112 women with dysmenorrhea who were randomly allocated into the four study groups.Finally,100 women complete the study and received capsules containing a placebo(n=25),1000 IU of Vitamin D(n=25),400 mg of Vitamin E(n=25),and 1000 IU of Vitamin D+400 mg of Vitamin E(n=25)every 24 h for 2 consecutive months at the beginning of the menstrual period.The pain intensity and duration among groups were compared before and after the intervention.Results:The mean menstrual pain duration in all three experimental groups(Vitamin E,Vitamin D,and the combination of them)was lower than the placebo group(all P<0.05),and the mean pain intensity scores in all three experimental groups were significantly lower than the placebo group(all P<0.05).The results(means)for all of the drugs administered at the end of the 2nd month were better than the 1st month(all P<0.01).Conclusions:Vitamin E and Vitamin D,as well as their combination,are recommended as an effective and safe treatment for the management of the complications of dysmenorrhea. 展开更多
关键词 dUrATION dYSMENOrrHEA intensity randomized controlled trial Vitamin d Vitamin E WOMEN
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云南省R&D经费投入结构动态研究
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作者 张和平 钟翔 +1 位作者 段江涛 贺新华 《中国科技资源导刊》 2024年第1期92-99,共8页
为研究云南省“十二五”以来R&D经费投入结构变化,分析R&D经费投入现状,并与全国,东、中、西部地区及临近省份进行了对比;从资金来源和资金配置视角,运用Cobb-Douglas效用函数及其修正模型对R&D经费投入结构展开动态分析。... 为研究云南省“十二五”以来R&D经费投入结构变化,分析R&D经费投入现状,并与全国,东、中、西部地区及临近省份进行了对比;从资金来源和资金配置视角,运用Cobb-Douglas效用函数及其修正模型对R&D经费投入结构展开动态分析。结果表明:云南省R&D经费投入结构不尽合理,资金来源中政府资金占比较低且呈下降趋势,资金配置中基础研究和应用研究投入不足,与最优结构偏离程度较大。针对存在的问题,提出持续加大政府R&D经费投入力度、围绕产业链提升基础研究和应用研究比重的建议。 展开更多
关键词 r&d经费 政府r&d投入 资源配置 活动类型 云南省 Cobb-douglas效用函数
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R&D资本化背景下我国TFP增长率再测算
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作者 杜瑶 许永洪 《统计研究》 北大核心 2024年第1期33-45,共13页
研究与试验发展(R&D)资本对经济增长和科技创新作用日益凸显,但对于R&D资本的核算亟待完善。本文基于SNA2008和CSNA2016框架,将R&D支出作为资本形成,对我国各省份物质资本存量和R&D资本存量进行规范化测算,使用随机前... 研究与试验发展(R&D)资本对经济增长和科技创新作用日益凸显,但对于R&D资本的核算亟待完善。本文基于SNA2008和CSNA2016框架,将R&D支出作为资本形成,对我国各省份物质资本存量和R&D资本存量进行规范化测算,使用随机前沿分析法重新估算1991—2019年间的全要素生产率(TFP)增长率。研究发现:第一,我国R&D资本存量规模呈总体递增和地区聚集趋势;第二,1991—2019年间,我国广义TFP增长率年平均增幅为2.10%,对经济增长存在正向作用;第三,将TFP增长率分解为技术进步、前沿技术效率和规模效应,发现技术进步对TFP增长率的贡献最大,是推动我国TFP增长的主导力量,但却呈现逐年递减的趋势;第四,随着我国对R&D投入的不断增加与重视,R&D对我国广义TFP增长率的贡献呈现递增的趋势,R&D的贡献逐渐成为推动我国科技进步的主要力量。 展开更多
关键词 r&d资本化 r&d资本存量 TFP增长率 随机前沿分析
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政府R&D资助对OFDI逆向绿色创新的影响机制研究
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作者 韩先锋 刘娟 李勃昕 《运筹与管理》 CSCD 北大核心 2024年第1期158-164,共7页
应用中国分省区层面数据并采用面板门槛模型,实证考察了政府R&D资助影响OFDI逆向绿色创新的动态效应。研究发现,OFDI对国内绿色创新产生了显著的驱动效应,但这种影响呈现出明显的先负后正的“U”型动态演化特征;政府R&D资助会... 应用中国分省区层面数据并采用面板门槛模型,实证考察了政府R&D资助影响OFDI逆向绿色创新的动态效应。研究发现,OFDI对国内绿色创新产生了显著的驱动效应,但这种影响呈现出明显的先负后正的“U”型动态演化特征;政府R&D资助会正向调节OFDI逆向绿色创新溢出,且存在最适宜于OFDI逆向绿色创新的政府R&D资助区间(0.366,0.428],过高或过低强度的政府R&D资助均会在一定程度上造成OFDI逆向绿色创新的红利损失;政府R&D资助调节下OFDI对绿色创新的动态影响具有显著时空异质性,即在时空维度上存在“激励效应”与“挤出效应”交替演化的鲜明特征。 展开更多
关键词 政府r&d资助 对外直接投资 绿色创新
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Airblast evolution initiated by Wangjiayan landslides in the M_(s)8.0 Wenchuan earthquake and its destructive capacity analysis
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作者 Yu-feng Wang Qian-gong Cheng Qi Zhu 《China Geology》 CAS CSCD 2024年第2期237-247,共11页
Airblasts,as one common phenomenon accompanied by rapid movements of landslides or rock/snow avalanches,commonly result in catastrophic damages and are attracting more and more scientific attention.To quantitatively a... Airblasts,as one common phenomenon accompanied by rapid movements of landslides or rock/snow avalanches,commonly result in catastrophic damages and are attracting more and more scientific attention.To quantitatively analyze the intensity of airblast initiated by landslides,the Wangjiayan landslide,occurred in the Wenchuan earthquake,is selected here with the landslide propagation and airblast evolution being studied using FLUENT by introducing the Voellmy rheological law.The results reveal that:(1)For the Wangjiayan landslide,its whole travelling duration is only 12 s with its maximum velocity reaching 36 m/s at t=10 s;(2)corresponding to the landslide propagation,the maximum velocity,28 m/s,of the airblast initiated by the landslide also appears at t=10 s with its maximum pressure reaching594.8 Pa,which is equivalent to violent storm;(3)under the attack of airblast,the load suffered by buildings in the airblast zone increases to 1300 Pa at t=9.4 s and sharply decreased to-7000 Pa as the rapid decrease of the velocity of the sliding mass at t=10 s,which is seriously unfavorable for buildings and might be the key reason for the destructive collapse of buildings in the airblast zone of the Wangjiayan landslide. 展开更多
关键词 LANdSLIdE Voellmy rheological law 3d FLUENT simulation Airblast intensity Building destructive collapse Wenchuan earthquake Geological hazards survey engineering
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Petrographic, Geochemical and Metallogenical Context of the Geological Formations of the Goumere Region (North-East of Cote D’Ivoire): Implication to the Knowledge of Gold Mineralization
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作者 Fossou Jean-Luc Hervé Kouadio Alain Nicaise Kouamelan +1 位作者 Topka Kakeu Lionel Boya Roger Nicaise Kanga 《International Journal of Geosciences》 CAS 2024年第2期180-203,共24页
The Gouméré region is located in the North-East of Côte d’Ivoire and is located in the South-West of the Bui furrow. In order to highlight the geology of the area studied, 14 samples were taken for stu... The Gouméré region is located in the North-East of Côte d’Ivoire and is located in the South-West of the Bui furrow. In order to highlight the geology of the area studied, 14 samples were taken for studies using petrographic, geochemical and metallogenic methods. The study of macroscopic and microscopic petrography made it possible to highlight two major lithological units: 1) a volcano-plutonic unit, formed of gabbros, basalt, volcaniclastics and rhyodacite;2) a sedimentary unit (microconglomerate). From a geochemical point of view, the results obtained indicate that the plutonites are gabbro and gabbro diorite while the volcanics have compositions of basaltic andesites, rhyolite and dacites. The sediments have a litharenitic to sublitharenitic character. The metallogenic study made it possible to highlight hydrothermal alterations and metalliferous paragenesis on the formations studied. Hydrothermal alteration is characterized by the presence of carbonation, silicification, sericitization, sulfidation and to a lesser degree chloritization. Metalliferous paragenesis consists of pyrite, chalcopyrite, hematite and magnetite. 展开更多
关键词 PETrOGrAPHY GEOCHEMISTrY METALLOGENY Gouméré Côte d’Ivoire
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政府采购对企业R&D投入的影响
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作者 张士博 赵雪键 +1 位作者 岳松森 李连伟 《山东工商学院学报》 2024年第1期46-56,107,共12页
针对政府采购对企业R&D投入激励的有效性问题,基于2011—2013年中国上市中小企业政府采购数据,采用倾向得分匹配法,研究政府采购、公司内部治理与企业R&D投入之间的关系。研究结果表明,政府采购能够有效促进企业R&D投入,且... 针对政府采购对企业R&D投入激励的有效性问题,基于2011—2013年中国上市中小企业政府采购数据,采用倾向得分匹配法,研究政府采购、公司内部治理与企业R&D投入之间的关系。研究结果表明,政府采购能够有效促进企业R&D投入,且这种影响因公司治理结构的不同而表现出明显的差异;政府采购对国有性质、股权分散、股权制衡及董事会规模较小的企业R&D投入的促进效应更加显著。 展开更多
关键词 政府采购 r&d投入 公司内部治理 倾向得分匹配法
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R&D投入对企业绩效影响的统计研究
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作者 蓝志清 汪洋 《河南科技》 2024年第3期154-157,共4页
【目的】对R&D投入与企业绩效的影响关系进行统计研究,为江西省上市公司进行R&D投入合理规划、提升企业绩效和促进创新驱动发展提供建议。【方法】基于江西省2019—2021年上市公司的面板数据,构建面板门槛回归模型,分析了R&... 【目的】对R&D投入与企业绩效的影响关系进行统计研究,为江西省上市公司进行R&D投入合理规划、提升企业绩效和促进创新驱动发展提供建议。【方法】基于江西省2019—2021年上市公司的面板数据,构建面板门槛回归模型,分析了R&D投入对企业绩效的门槛效应。【结果】单一门槛、双重门槛、三重门槛均通过了显著性检验,在不同门槛值区间时,R&D投入对企业绩效的边际系数符号及其显著性存在明显差异。【结论】企业应根据自身所处的R&D投入区间合理制定相应的研发计划,当企业R&D投入处于低区间时,应当加大R&D投入;当R&D投入上升至一定区间时,则需重点关注R&D投入效率问题,以避免R&D投入对企业绩效的抑制作用。 展开更多
关键词 r&d投入 企业绩效 面板门槛回归模型
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江西省R&D经费投入的特征分析及提升对策研究
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作者 梅丁丁 王金凤 +1 位作者 童金杰 卢婷 《科技广场》 2024年第2期68-74,共7页
本文分析近年来江西省R&D经费投入的特征及问题,研究表明:江西省R&D经费投入总量和强度均保持较快增长,但还存在投入总量规模不大、结构不优、财政资金投入相对较少等问题,并从强化企业创新主体地位、加大财政资金支持力度、提... 本文分析近年来江西省R&D经费投入的特征及问题,研究表明:江西省R&D经费投入总量和强度均保持较快增长,但还存在投入总量规模不大、结构不优、财政资金投入相对较少等问题,并从强化企业创新主体地位、加大财政资金支持力度、提升科技金融支持研发创新以及提升科技统计质量等方面提出了对策建议,为江西省提升全社会研发投入水平,加快创新型省份建设提供了决策参考。 展开更多
关键词 科技统计 r&d投入 创新型省份
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数字经济对R&D投入创新绩效的影响研究
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作者 李燕 鲜于乐娇 《新经济》 2024年第6期31-45,共15页
数字经济是当今各国科技创新和产业提质增效及重塑核心竞争力的必备基础。研究现阶段地区数字经济发展水平及其对R&D投入创新绩效的影响,对推进我国地区数字经济和科技创新发展有重要意义。研究首先基于熵值法测算研究地区数字经济... 数字经济是当今各国科技创新和产业提质增效及重塑核心竞争力的必备基础。研究现阶段地区数字经济发展水平及其对R&D投入创新绩效的影响,对推进我国地区数字经济和科技创新发展有重要意义。研究首先基于熵值法测算研究地区数字经济发展水平和基于Super-SBM方法测算地区R&D投入创新绩效,然后运用静态面板模型、动态面板模型和动态空间杜宾模型多重实证分析方法分析地区数字经济发展水平对创新绩效的影响。实证分析结果显示,地区数字经济对R&D投入创新绩效有正向影响,数字经济发展水平和R&D投入创新绩效均高的地区主要集中在京津冀、长三角和珠三角。研究结果对进一步制定数字经济发展相关政策建议来推动科技创新提供了依据。 展开更多
关键词 数字经济 r&d 投入 创新绩效 空间杜宾模型
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Basal internode elongation of rice as affected by light intensity and leaf area 被引量:4
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作者 Xuhua Zhong Kaiming Liang +5 位作者 Bilin Peng Ka Tian Xiaojuan Li Nongrong Huang Yanzhuo Liu Junfeng Pan 《The Crop Journal》 SCIE CAS CSCD 2020年第1期62-70,共9页
Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of bas... Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of basal internodes persists.The objectives of this study were(1)to identify key factors affecting the elongation of basal internodes and(2)to establish a quantitative relationship between basal internode length and canopy indices.An inbred rice cultivar,Yinjingruanzhan,was grown in two split-plot field experiments with three N rates(0,75,and 150 kg N ha−1 in early season and 0,90,and 180 kg N ha−1 in late season)as main plots,three seedling densities(16.7,75.0,and 187.5 seedlings m−2)as subplots,and three replications in the 2015 early and late seasons in Guangzhou,China.Light intensity at base of canopy(Lb),light quality as determined from red/far-red light ratio(R/FR),light transmission ratio(LTR),leaf area index(LAI),leaf N concentration(NLV)and final length of second internode(counted from soil surface upward)(FIL)were recorded.Higher N rate and seedling density resulted in significantly longer FIL.FIL was negatively correlated with Lb,LTR,and R/FR(P<0.01)and positively correlated with LAI(P<0.01),but not correlated with NLV(P>0.05).Stepwise linear regression analysis showed that FIL was strongly associated with Lb and LAI(R2=0.82).Heavy N application to pot-grown rice at the beginning of first internode elongation did not change FIL.We conclude that FIL is determined mainly by Lb and LAI at jointing stage.NLV has no direct effect on the elongation of basal internodes.N application indirectly affects FIL by changing LAI and light conditions in the rice canopy.Reducing LAI and improving canopy light transmission at jointing stage can shorten the basal internodes and increase the lodging resistance of rice. 展开更多
关键词 Internode elongation Leaf area index Light intensity Light quality r/Fr Light transmission ratio Leaf N concentration
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Impact of Ownership Types on R&D Intensity and Innovation Performance--Evidence from Transitional China 被引量:7
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作者 Da Teng Jingtao Yi 《Frontiers of Business Research in China》 2017年第1期101-137,共37页
这份报纸在公司 R&D 紧张和革新性能上检验所有权类型的效果,用从 2005 ~ 2007 的 357,857 个中国公司的一件样品。这研究以 R&D 紧张和革新性能在中国国内企业之中发现可观的分叉。,我们发现中央政府拥有的公司是为公司 R&a... 这份报纸在公司 R&D 紧张和革新性能上检验所有权类型的效果,用从 2005 ~ 2007 的 357,857 个中国公司的一件样品。这研究以 R&D 紧张和革新性能在中国国内企业之中发现可观的分叉。,我们发现中央政府拥有的公司是为公司 R&D 活动的关键司机本地管理,私人、外国的所有权是否定地与 R&D 紧张和革新性能有关。这份报纸在政府所有权范畴以内发现重要分叉并且主张瓷器机构的变化与资源天赋的不同层次产生改变的政府所有权组,它接着影响公司 R&D 活动。 展开更多
关键词 中国企业 所有制 研发 绩效 创新 强度 类型 中央政府
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Effects of investment on energy intensity:evidence from China 被引量:2
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作者 Junbing Huang Shiwei Yu 《Chinese Journal of Population,Resources and Environment》 2016年第3期197-207,共11页
This article explores the effects of investment upon energy intensity by applying a unique panel data of China's 27 provinces between 2004 and 2013.In addition,it also particularly stuthes other factors,such as en... This article explores the effects of investment upon energy intensity by applying a unique panel data of China's 27 provinces between 2004 and 2013.In addition,it also particularly stuthes other factors,such as energy price,economic structure,and urbanization.The results,based on four econometric regression model results,suggest that in general,the indigenous investment on research and development is a more powerful tool to decrease China's energy intensity regardless of region disparity.The foreign direct investment(FDI) has a prominent but not persistent effect on energy intensity.However,the outward direct investment has not shown its significant impact on energy intensity.At the level of an aggregate economy and China's eastern region,the results demonstrate that FDI improves energy efficiency significantly.For the central and western provinces,FDI does not support the similar conclusion.Based on these analyses,we present the corresponding regional policies for policymakers. 展开更多
关键词 Energy intensity research and development(r&d) foreign direct investment outward direct investment
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D″anisotropy inverted from shear wave splitting intensity 被引量:1
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作者 Chao Zhang Zhouchuan Huang 《Earthquake Science》 2022年第2期93-104,共12页
The D″layer,located at the bottom of the mantle,is an active thermochemical boundary layer.The upwelling of mantle plumes,as well as possible plate subduction in the D″layer,could lead to large-scale material transf... The D″layer,located at the bottom of the mantle,is an active thermochemical boundary layer.The upwelling of mantle plumes,as well as possible plate subduction in the D″layer,could lead to large-scale material transformation and mineral deformation,which could result in significant seismic anisotropy.However,owing to limited observations and immense computational cost,the anisotropic structures and geodynamic mechanisms in the D″layer remain poorly understood.In this study,we proposed a new inversion method for the seismic anisotropy in the D″layer quantitatively with shear wave splitting intensities.We first proved the linearity of the splitting intensities under the ray-theory assumption.The synthetic tests showed that,with horizontal axes of symmetry and ray incidences lower than 30°in the D″layer(typical SKS phase),the anisotropy is well resolved.We applied the method to the measured dataset in Africa and Western Europe,and obtained strong D″anisotropy in the margins of the large low shear-wave velocity provinces and subducting slabs.The new method makes it possible to obtain D″anisotropy,which provides essential constraints on the geodynamical processes at the base of the mantle. 展开更多
关键词 seismic anisotropy splitting intensity d″layer PLUME SLAB
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THE ANALYSIS OF DYNAMIC STRESS INTENSITY FACTOR FOR SEMI-CIRCULAR SURFACE CRACK USING TIME-DOMAIN BEM FORMULATION 被引量:1
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作者 ZHONG Ming(钟明) +1 位作者 ZHANG Yong-yuan(张永元) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第11期1344-1351,共8页
The time-domain BEM was developed to analyze the dynamic stress intensity factor ( DSIF) of 3-D elastodynamic crack problems. To simulate the stress singularity along the front of a crack, eight-node isoparametric sin... The time-domain BEM was developed to analyze the dynamic stress intensity factor ( DSIF) of 3-D elastodynamic crack problems. To simulate the stress singularity along the front of a crack, eight-node isoparametric singular elements were used, and the DSIF for a semi-circular surface crack was firstly calculated based on displacement equation using the time-domain BEM formulation. The new scheme to determine the time step was brought forward. By the dynamic analysis program of time-domain BEM compiled by its, several numerical examples are presented, which demonstrate the unconditional stability and high accuracy of time-domain BEM applied to 3-D elastodynamic crack problems. 展开更多
关键词 time-domain BEM 3-d elastodynamic crack problems dynamic stress intensity factor
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中国五大城市群R&D资本存量差异与分布特征 被引量:1
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作者 倪青山 卢彦瑾 《财经理论与实践》 北大核心 2023年第1期107-113,共7页
使用Dagum基尼系数、描述性统计等方法,研究中国五大城市群R&D资本存量差异与分布特征。结果显示:中国五大城市群R&D资本存量差异大,但呈缓慢下降趋势,差异主要来源于不同城市群之间;不同城市群内部以及不同城市群之间R&D... 使用Dagum基尼系数、描述性统计等方法,研究中国五大城市群R&D资本存量差异与分布特征。结果显示:中国五大城市群R&D资本存量差异大,但呈缓慢下降趋势,差异主要来源于不同城市群之间;不同城市群内部以及不同城市群之间R&D资本存量差异大小及其演进趋势具有显著差异。R&D资本存量向五大城市群特别是长三角城市群以及粤港澳大湾区集聚。五大城市群内部R&D资本存量分布特点及演进趋势各不相同。鉴于此,揭示了中国五大城市群R&D资本存量差异与分布特征,从而为城市创新发展战略及政策制定提供理论依据。 展开更多
关键词 城市群 城市r&d资本存量 差异 分布
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政府补助、财务分析师与企业R&D创新——基于财务分析师跟踪强度与预测偏差度的视角
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作者 陈静 柏婷 李国兰 《重庆理工大学学报(社会科学)》 CAS 2023年第10期92-105,共14页
基于我国沪深A股上市企业2015—2019年的非平衡面板数据,从创新投入的数量和质量角度综合考察政府补助对上市企业R&D创新的影响,以及财务分析师对两者关系的调节作用。结果表明:(1)政府补助与企业R&D创新显著正相关,即政府补助... 基于我国沪深A股上市企业2015—2019年的非平衡面板数据,从创新投入的数量和质量角度综合考察政府补助对上市企业R&D创新的影响,以及财务分析师对两者关系的调节作用。结果表明:(1)政府补助与企业R&D创新显著正相关,即政府补助能有效提升企业R&D投入和R&D产出水平;并且这种激励效应主要集中在国有企业和大型企业中。(2)财务分析师跟踪强度对政府补助与企业R&D创新之间的正相关关系具有显著的正向调节作用。财务分析师跟踪强度的增加,导致其出具的预测报告与企业真实经营情况之间存在偏差,财务分析师跟踪预测偏差度会稀释财务分析师的信息中介和外部治理作用,即财务分析师预测偏差度对政府补助与企业R&D创新之间的正相关性具有显著的负向调节作用。据此,为相关部门优化资本市场中介机构、促进上市企业R&D创新提供政策制定依据。 展开更多
关键词 政府补助 财务分析师 跟踪强度 预测偏差度 r&d创新
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环境规制、R&D资本存量与绿色技术创新 被引量:1
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作者 陈宇科 王猛利 《重庆师范大学学报(社会科学版)》 2023年第2期29-44,共16页
科技创新是一个国家经济发展的内生动力。技术创新能力的提升需要持续的R&D投入,而R&D资本存量正是衡量持续研发投入水平的最佳指标。本文基于BEA原理,合理测算出中国内地30个省区市(西藏除外)的R&D资本存量,并采用省际面... 科技创新是一个国家经济发展的内生动力。技术创新能力的提升需要持续的R&D投入,而R&D资本存量正是衡量持续研发投入水平的最佳指标。本文基于BEA原理,合理测算出中国内地30个省区市(西藏除外)的R&D资本存量,并采用省际面板数据,构建空间计量模型,探讨环境规制下R&D资本存量对绿色技术创新的影响机制。研究表明:环境规制与R&D资本存量对绿色技术创新均具有促进作用,但一定强度的环境规制会挤占R&D投入资源,与R&D资本存量的累积发生“负挤出效应”,进而影响绿色技术创新;同时,R&D资本存量、环境规制对中国东部、中部与西部地区的绿色技术创新的影响呈现显著的区域异质性。因此,本文提出了制定差异化的R&D投资和环境规制策略。 展开更多
关键词 环境规制 r&d资本存量 绿色技术创新 空间计量
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债务期限结构错配抑制了高科技企业R&D投入吗?——基于认证高新技术企业的经验证据
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作者 熊莉 李红松 《湖南财政经济学院学报》 2023年第2期87-98,共12页
选取认证高新技术企业为样本,将债务水平与债务-资产期限结构配置纳入统一分析框架,并充分考虑两者的内生关系,考察债务期限结构错配对高科技企业R&D投入强度的影响。结果表明:债务杠杆对高科技企业后期R&D投入强度存在显著的... 选取认证高新技术企业为样本,将债务水平与债务-资产期限结构配置纳入统一分析框架,并充分考虑两者的内生关系,考察债务期限结构错配对高科技企业R&D投入强度的影响。结果表明:债务杠杆对高科技企业后期R&D投入强度存在显著的负面影响,但影响呈减弱趋势;“短债长用”类错配对高科技企业R&D投入强度存在一定程度的正面促进作用,而“长债短用”类错配则抑制了R&D投入;债务杠杆与债务期限结构配置之间存在影响R&D投入的正面交互效应,交互效应的存在强化了债务杠杆的负面影响和债务期限错配的积极作用,采用“低杠杆”加“短债长用”错配组合,更有利于促进高科技企业R&D投入。 展开更多
关键词 债务杠杆 债务期限结构错配 r&d投入 高科技企业
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