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The Design for R&D Performance Auditing System
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作者 Haisheng Chen Jinhua Chen 《Journal of Modern Accounting and Auditing》 2006年第4期76-81,共6页
Based on the definition of R&D pcrformance auditing system, this paper analyzes the characteristics of the system. Then it designs the components of the R&D performance auditing system and the procedure of its estab... Based on the definition of R&D pcrformance auditing system, this paper analyzes the characteristics of the system. Then it designs the components of the R&D performance auditing system and the procedure of its establishment. 展开更多
关键词 r&d performance auditing system COMPONENTS design procedure
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D-S理论和Markov链组合的桥梁性能退化预测研究
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作者 杨国俊 田里 +2 位作者 唐光武 毛建博 杜永峰 《应用数学和力学》 CSCD 北大核心 2024年第4期416-428,共13页
为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的... 为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的预测数据序列,并利用Markov链和D-S理论不断进行优化,从而实现桥梁性能退化的组合预测.实际工程的应用结果表明:性能退化率可以直观地表征在梁性能退化的速度.其次,该模型的平均相对误差为1.54%,较于回归、灰色和模糊加权Markov链模型,精度分别提高了1.11%,0.88%和2.8%,而后验差比值为0.242,小于0.35;模型的标准差为9.021,相比其他模型分别减小了3.978,3.405和7.500,而变异系数为0.109,均小于其他模型,验证了组合预测模型在精度和稳定性方面的优越性,可为在役桥梁结构性能退化预测与维护提供理论基础. 展开更多
关键词 桥梁工程 性能退化预测 d-S证据理论 MArKOV链 组合预测模型 桥梁性能退化率
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政府R&D补贴的技术创新效应分析--基于2009-2021年中国的经验数据
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作者 臧传琴 《山东商业职业技术学院学报》 2024年第4期1-8,共8页
政府R&D补贴既可以通过提供公共服务的方式直接作用于技术创新,也可以通过对社会资本的引导作用间接影响技术创新,其总效应取决于两种影响的方向与大小。基于2009—2021年中国的经验数据,建立了由技术创新方程和引致方程共同组成的... 政府R&D补贴既可以通过提供公共服务的方式直接作用于技术创新,也可以通过对社会资本的引导作用间接影响技术创新,其总效应取决于两种影响的方向与大小。基于2009—2021年中国的经验数据,建立了由技术创新方程和引致方程共同组成的动态模型,对政府R&D补贴的技术创新效应进行了实证分析。结果发现:持续增加的政府R&D补贴带来了国内专利授权数量的稳定增加,技术创新效应较为显著;政府R&D补贴不仅对技术创新产生了积极的直接影响,也通过引导社会资本投资于研发领域而对技术创新产生了积极的间接影响;政府R&D补贴的技术创新效应存在区域差异,中东部地区为正,而西部地区为负。提高资金使用效率、积极引导社会资本投资技术研发、努力改善欠发达地区的研发环境,无疑是提高政府R&D补贴技术创新效应的必要选择。 展开更多
关键词 r&d补贴 技术创新 直接效应 间接效应
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云南省R&D经费投入结构动态研究 被引量:1
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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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政府R&D资助对OFDI逆向绿色创新的影响机制研究 被引量:1
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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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Development and identification of two novel wheat-rye 6R derivative lines with adult-plant resistance to powdery mildew and high-yielding potential 被引量:1
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作者 Guohao Han Jing Wang +10 位作者 Hanwen Yan Tiantian Gu Lijun Cao Shiyu Liu Xiuquan Li Yilin Zhou Jieru Fan Zhipeng Shi Hong Liu Lihui Li Diaoguo An 《The Crop Journal》 SCIE CSCD 2024年第1期308-313,共6页
Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared wit... Powdery mildew,caused by Blumeria graminis f.sp.tritici(Bgt),is a devastating disease that seriously threatens wheat yield and quality.To control this disease,host resistance is the most effective measure.Compared with the resistance genes from common wheat,alien resistance genes can better withstand infection of this highly variable pathogen.Development of elite alien germplasm resources with powdery mildew resistance and other key breeding traits is an attractive strategy in wheat breeding.In this study,three wheat-rye germplasm lines YT4-1,YT4-2,and YT4-3 were developed through hybridization between octoploid triticale and common wheat,out of which the lines YT4-1 and YT4-2 conferred adult-plant resistance(APR)to powdery mildew while the line YT4-3 was susceptible to powdery mildew during all of its growth stages.Using genomic in situ hybridization,multi-color fluorescence in situ hybridization,multi-color GISH,and molecular marker analysis,YT4-1,YT4-2,and YT4-3 were shown to be cytogenetically stable wheat-rye 6R addition and T1RS.1BL translocation line,6RL ditelosomic addition and T1RS.1BL translocation line,and T1RS.1BL translocation line,respectively.Compared with previously reported wheat-rye derivative lines carrying chromosome 6R,YT4-1 and YT4-2 showed stable APR without undesirable pleiotropic effects on agronomic traits.Therefore,these novel wheat-rye 6R derivative lines are expected to be promising bridge resources in wheat disease breeding. 展开更多
关键词 Powdery mildew Secale cereale Triticum aestivum Wheat-rye 6r derivatives Agronomic performance
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Additively manufactured Ti–Ta–Cu alloys for the next-generation load-bearing implants 被引量:1
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作者 Amit Bandyopadhyay Indranath Mitra +4 位作者 Sushant Ciliveri Jose D Avila William Dernell Stuart B Goodman Susmita Bose 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期353-374,共22页
Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the m... Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the most efficient defense against colonization, especially in the case of secondary infection, leading to surgical removal of implants and in some cases even limbs. In this study, laser powder bed fusion was implemented to fabricate Ti3Al2V alloy by a 1:1 weight mixture of CpTi and Ti6Al4V powders. Ti-Tantalum(Ta)–Copper(Cu) alloys were further analyzed by the addition of Ta and Cu into the Ti3Al2V custom alloy. The biological,mechanical, and tribo-biocorrosion properties of Ti3Al2V alloy were evaluated. A 10 wt.% Ta(10Ta) and 3 wt.% Cu(3Cu) were added to the Ti3Al2V alloy to enhance biocompatibility and impart inherent bacterial resistance. Additively manufactured implants were investigated for resistance against Pseudomonas aeruginosa and Staphylococcus aureus strains of bacteria for up to 48 h. A 3 wt.% Cu addition to Ti3Al2V displayed improved antibacterial efficacy, i.e.78%–86% with respect to CpTi. Mechanical properties for Ti3Al2V–10Ta–3Cu alloy were evaluated, demonstrating excellent fatigue resistance, exceptional shear strength, and improved tribological and tribo-biocorrosion characteristics when compared to Ti6Al4V. In vivo studies using a rat distal femur model revealed improved early-stage osseointegration for alloys with10 wt.% Ta addition compared to CpTi and Ti6Al4V. The 3 wt.% Cu-added compositions displayed biocompatibility and no adverse infammatory response in vivo. Our results establish the Ti3Al2V–10Ta–3Cu alloy’s synergistic effect on improving both in vivo biocompatibility and microbial resistance for the next generation of load-bearing metallic implants. 展开更多
关键词 TI6AL4V load-bearing implants additive manufacturing 3d printing antibacterial performance
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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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Antecedents and performance consequences of governance structures in R&D alliances 被引量:1
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作者 林艺馨 荷世平 吴学良 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期360-366,共7页
Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research an... Traditionally governance structures are classified into "hierarchy or market" or "equity or non-equity." However,such classifications may not be effective in characterizing all governance structures of research and development(R D) alliances.Therefore,the first objective of this study is to investigate why there exist different organizational governance structures in managing R D alliances;the second objective of this study is to give strategic advice in choosing appropriate forms with respect to various characteristics of R D alliances.Through the theoretical lens that integrate both transaction cost economics(TCE) and the resource-based view(RBV),a model that focuses on six major factors is developed for determining governance structure choices,namely,technological uncertainty,cultural difference,asset specificity,technology complementarity,appropriability of the individual firm's know-how,and trust.An R D alliance with higher technological uncertainty,larger cultural differences,and greater concerns for protecting an individual's know-how is more likely to adopt non-integrated alliances as the governing structure.An R D alliance with a higher degree of asset-specificity,greater technology complementarity and greater trust among partnering organizations is more likely to adopt integrated alliances as the governing structure;an R D alliance in the face of lower technological uncertainty will tend to adopt integrated alliances.The more aligned the choice of the governance structure with its determinants,the better the R D alliance will perform,and vice versa. 展开更多
关键词 organizational governance structure organizational control resource-based review transaction cost economics r& d alliance
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High Performance 70nm CMOS Devices
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作者 徐秋霞 钱鹤 +5 位作者 殷华湘 贾林 季红浩 陈宝钦 朱亚江 刘明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第2期134-139,共6页
A high performance 70nm CMOS device has been demonstrated for the first time in the continent, China. Some innovations in techniques are applied to restrain the short channel effect and improve the driving ability, ... A high performance 70nm CMOS device has been demonstrated for the first time in the continent, China. Some innovations in techniques are applied to restrain the short channel effect and improve the driving ability, such as 3nm nitrided oxide, dual poly Si gate electrode, novel super steep retrograde channel doping by heavy ion implantation, ultra shallow S/D extension formed by Ge PAI(Pre Amorphism Implantation) plus LEI(Low Energy Implantation), thin and low resistance Ti SALICIDE by Ge PAI and special cleaning, etc. The shortest channel length of the CMOS device is 70nm. The threshold voltages, G m and off current are 0 28V,490mS·mm -1 and 0 08nA/μm for NMOS and -0 3V,340mS·mm -1 and 0 2nA/μm for PMOS, respectively. Delays of 23 5ps/stage at 1 5V, 17 5ps/stage at 2 0V and 12 5ps/stage at 3V are achieved in the 57 stage unloaded 100nm CMOS ring oscillator circuits. 展开更多
关键词 high performance 70nm CMOS device S/d extension nitrided gate oxide Ge PAI SALICIdE
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政府补助与R&D投入对智慧养老企业绩效的影响研究
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作者 张旭东 赵怡 《科技与经济》 2024年第4期71-75,共5页
在老龄化背景下,智慧养老行业蓬勃发展。政府为缓解老龄化压力,加大对智慧养老企业的补贴力度,企业要想在激烈的竞争中实现可持续化发展,必须进行研发创新。以智慧养老企业为研究对象,分别探讨政府补助、研发投入以及二者能否产生交互... 在老龄化背景下,智慧养老行业蓬勃发展。政府为缓解老龄化压力,加大对智慧养老企业的补贴力度,企业要想在激烈的竞争中实现可持续化发展,必须进行研发创新。以智慧养老企业为研究对象,分别探讨政府补助、研发投入以及二者能否产生交互效应来提升智慧养老企业绩效,以期为智慧养老企业转型升级谋求道路。研究表明:政府补助与研发投入均能够正向提升智慧养老企业绩效,但具有滞后性;二者具有互补性,能够产生交互效应,共同提升智慧养老企业绩效。 展开更多
关键词 智慧养老企业 政府补助 研发投入 企业绩效 交互效应
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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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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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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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基于Tobit模型的河南省R&D投入产出影响因素分析
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作者 王新 《河南科技》 2024年第10期144-148,共5页
【目的】科技创新能力是地区综合实力的重要标志之一,科学地识别影响科技资源投入产出的因素,是实现经济跨越式发展和可持续发展的关键。【方法】基于Tobit模型对近十年河南省R&D投入产出面板数据进行相关检验,分析得出各变量对河南... 【目的】科技创新能力是地区综合实力的重要标志之一,科学地识别影响科技资源投入产出的因素,是实现经济跨越式发展和可持续发展的关键。【方法】基于Tobit模型对近十年河南省R&D投入产出面板数据进行相关检验,分析得出各变量对河南省R&D投入产出产生的不同影响。【结果】企业研发机构投入和高水平人才比例与河南省R&D投入产出效率呈显著正相关,而政府支持力度和对外开放程度则对R&D投入产出效率的作用不显著。【结论】建议河南省通过转换政府职能、注重人才引进、加强对外交流、改善区域环境等方式,优化R&D投入产出,更好地提升科技效能。 展开更多
关键词 r&d 影响因素 TOBIT模型
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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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An Analysis of Liberia’s Vulnerability to Climate Change in the Context of Least Developed Countries (LDCs): A Review
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作者 Charles Flomo Togbah 《American Journal of Climate Change》 2024年第2期230-250,共21页
Climate change is an alarming global challenge, particularly affecting the least developed countries (LDCs) including Liberia. These countries, located in regions prone to unpredictable temperature and precipitation c... Climate change is an alarming global challenge, particularly affecting the least developed countries (LDCs) including Liberia. These countries, located in regions prone to unpredictable temperature and precipitation changes, are facing significant challenges, particularly in climate-sensitive sectors such as mining and agriculture. LDCs need more resilience to adverse climate shocks but have limited capacity for adaptation compared to other developed and developing nations. This paper examines Liberia’s susceptibility to climate change as a least developed country, focusing on its exposure, sensitivity, and adaptive capacity. It provides an overview of LDCs and outlines the global distribution of carbon dioxide emissions. The paper also evaluates specific challenges that amplify Liberia’s vulnerability and constrain sustainable adaptation, providing insight into climate change’s existing and potential effects. The paper emphasizes the urgency of addressing climate impacts on Liberia and calls for concerted local and international efforts for effective and sustainable mitigation efforts. It provides recommendations for policy decisions and calls for further research on climate change mitigation and adaptation. 展开更多
关键词 Least developed Countries LIBErIA Climate Change VULNErABILITY POVErTY HUNGEr disease research and development (r&d) Adaptation
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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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广东省R&D资本存量的测度、生产效率与政策效应
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作者 杨新洪 《深圳社会科学》 2024年第5期69-81,共13页
本文研究目的是计算广东省R&D资本存量,探讨R&D资本化对GDP的影响,并以此考察工业企业R&D生产效率的影响因素及相关政策效果。采用2010—2020年广东省及21个地市工业企业面板数据,使用永续盘存法测算广东省及21个地市的R&am... 本文研究目的是计算广东省R&D资本存量,探讨R&D资本化对GDP的影响,并以此考察工业企业R&D生产效率的影响因素及相关政策效果。采用2010—2020年广东省及21个地市工业企业面板数据,使用永续盘存法测算广东省及21个地市的R&D资本存量,并使用R&D强度,更好地反映了R&D投入状况。在计算R&D资本存量的基础上,构建柯布-道格拉斯知识生产函数模型进行分析,发现R&D资本存量和研发人员投入对R&D产出具有显著正效应,但研发人员产出弹性远高于资本存量,其中全时非全时工作人员比对新产品销售收入也具有显著正效应。企业规模、高薪技术企业减免税对R&D产出均具有显著正效应,但国有产权增加会导致R&D产出的下降,另外,境外技术引进仅对新产品销售收入具有显著正效应。最后,使用DID模型和平行趋势检验进行广东省内21个地市的政策评估,发现政策实施四年后对R&D劳动投入出现显著负效应,说明政策实施导致企业R&D劳动力投入下降,对广东省“十二五”后相关地市R&D政策效应评估为广东省未来R&D政策的制定提供了重要参考。根据研究结果,提出以下政策建议:在政策的设定上,应设定更合理的高薪企业认定标准,并考虑企业可能存在的欺骗空间,确保政策资金的扶持更为合理地流动;在R&D政策制定上,应更多刺激民营经济的科技创新活力,加快形成新质生产力。同时,应充分发挥R&D政策的示范引领效应,促进企业更新升级。 展开更多
关键词 新质生产力 r&d资本存量 GdP影响度测算 知识生产函数 dId模型 生产 效率 政策效应 高质量发展
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Relationship of serum vitamin D level on geriatric syndromes and physical performance impairment in elderly hypertensive patients 被引量:9
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作者 Xing-Kun ZENG Shan-Shan SHEN +3 位作者 Jiao-Jiao CHU Ting HE Lei CHENG Xu-Jiao CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第6期537-545,共9页
Objective To investigate the relationship among serum vitamin D levels, physical performance impairment, and geriatric syndromes in elders with hypertension. Methods According to the concentration of vitamin D levels,... Objective To investigate the relationship among serum vitamin D levels, physical performance impairment, and geriatric syndromes in elders with hypertension. Methods According to the concentration of vitamin D levels, a total of 143 elderly patients with hypertension were classified into vitamin D deficient group (vitamin D 〈 20 ng/mL, n = 94) and vitamin D appropriate group (vitamin D 〉 20 ng/rnL, n = 49). Geriatric syndromes and physical performance were assessed by using comprehensive geriatric assessment (CGA). Correlation among vitamin D levels, geriatric syndromes and physical performance was analyzed. Results No statistical differences were found in various aspects of geriatric syndromes between the two groups (P 〉 0.05). While correlation analysis indicated that vitamin D levels had a positive association with ADL score (r = 0.235, P 〈 0.01) and a negative association with Morse fall scale score (r = 0.238, P 〈 0.01). Patients with deficient vitamin D level had longer time both in the Five Time Sit to Stand Test (5tSTS), (15.765 ± 5.593) and the four-meter walk test [7.440 (5.620, 9.200)], a weaker hand-grip in the grip strength test (28.049 ± 9.522), and a lower Tinetti performance-oriented mobility assessment (Tinetti POMA) [26 (22, 27)] and Balance subscale of the Tinetti performance-oriented mobility assessment (B-POMA) score [ 14 (12, 16)], compared with appropriate vitamin D level [(13.275 ± 3.692); 5.810 (4.728, 7.325)]; (31.989 ± 10.217); [26.5 (25, 28)]; [15 (14, 16), respectively, all P 〈 0.05]. Furthermore, results of logistic regression indicated that vitamin D was significantly associated with 5tSTS (OR = 1.2, 95% CI = 1.050-1.331, P 〈 0.01), Tinetti POMA (OR = 3.7, 95% CI:1.284-10.830, P 〈 0.05) and B-POMA (OR = 0.8, 95% CI:0.643-0.973, P 〈 0.05). Conclusions In elderly hypertensive patients, serum vitamin D deficient level is associated with physical performance impairment. However, no statistical significance was found between vitamin D and geriatric syndromes. Further study is required to investigate possible mechanisms for the association between vitamin D and physical performance. 展开更多
关键词 ELdErLY Geriatric syndromes HYPErTENSION Physical performance Vitamin d
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