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1.
以长江经济带124个地级市、自治州和2个直辖市为研究单元,用专利授权量表征创新产出,运用标准差、变异系数、ESDA和空间计量经济模型等方法对1986—2014年长江经济带创新产出的时空演变特征及形成机制进行探讨。研究表明:(1)长江经济带创新产出的绝对差异在2001年以前增加缓慢,其后迅速拉大,2012年后明显下降;相对差异在1994年以前大致呈下降趋势,其后缓慢增加,2002年后增加显著,在2003年达到最高点,2009年后出现明显的下降。(2)长江经济带创新产出高的地市数量变化不大,分布较为集中,但有向中部地区蔓延的趋势,主要位于长三角地区及中西部的省会城市。(3)长江经济带创新产出的空间关联特征以正相关为主,空间集聚特征明显且空间格局大致稳定,长三角地区一直都是创新产出密集聚集的地区,而中西部地区大多是低低集聚地区,高低集聚的地市主要是中西部一些省会城市区。(4)空间交互作用是长江经济带创新产出产生空间差异的重要原因,科技投入和科技政策对长江经济带创新产出具有显著影响,经济发展、人才资源、FDI及通讯基础设施对创新产出也具有较大影响,传统基础设施对创新产出作用最小,而外资在区域经济中的渗透程度对创新产出具有抑制作用。 相似文献
2.
采用超效率EBM模型对2013—2019年长江经济带36个城市的绿色创新效率进行测度,通过构建修正引力模型得到城市间绿色创新效率的空间关联矩阵,运用社会网络分析法和QAP分析法从网络化视角探索长江经济带城市绿色创新效率的空间网络关联特征和形成机理.研究表明:(1)研究期间长江经济带城市绿色创新效率空间关联强度处于下降趋势,等级结构特征比较明显,下游城市在空间网络中处于相对中心的位置,而中上游城市处于相对劣势地位;(2)长江经济带城市绿色创新效率集聚板块特征呈现板块内集聚、板块之间存在一定空间关联;(3)城市环保、科研投入差异有利于长江经济带城市绿色创新效率空间网络的形成,城市距离、开放、创新水平差异则对其有负向影响.为促进长江经济带城市可持续发展,提出将长江经济带城市看作一个整体,在提升绿色创新效率时注重城市间的协同关系和联动效应;打破长江经济带绿色创新效率的马太效应,优化整体格局;进一步完善各城市的交通设施,推进路网规划设施建设等建议. 相似文献
3.
采用超效率EBM模型对2013 － 2019年长江经济带36个城市的绿色创新效率进行测度,通过构建修正引力模型得到城市间绿色创新效率的空间关联矩阵,运用社会网络分析法和QAP分析法从网络化视角探索长江经济带城市绿色创新效率的空间网络关联特征和形成机理。研究表明：①研究期间长江经济带城市绿色创新效率空间关联强度处于下降趋势,等级结构特征比较明显;②长江经济带下游城市在空间网络中处于相对中心的位置,而中上游城市处于相对劣势地位。③长江经济带城市绿色创新效率集聚板块特征：板块内集聚,板块之间存在一定空间关联。④城市环保、科研投入差异有利于长江经济带城市绿色创新效率空间网络的形成,城市距离、开放、创新水平差异则对其有负向影响。 相似文献
4.
经济集聚促进长江经济带区域经济发展的同时也会影响环境质量,为探讨经济集聚对工业废水排放的影响效应,本文基于2003—2017年长江经济带110个地级及以上城市面板数据,采用探索性空间数据分析、空间计量模型和门槛回归模型等方法,考察经济集聚与工业废水排放的空间分布与聚类状况,解析经济集聚对工业废水排放影响的空间溢出效应并验证其门槛特征。结果表明：①经济集聚、工业废水排放总量和排放强度均存在显著的正向空间自相关性,长三角地区经济集聚与工业废水排放总量多呈现“高-高”型聚类,长江上游地区多为“低-低”型聚类,且保持较为稳定的态势;而工业废水排放强度的聚类状况则呈现出较大差异;②经济集聚存在明显的空间溢出效应且抑制工业废水排放的直接效应和间接效应均较为显著,集聚过程中经济发展水平、人口密度、二产占比和交通便利度提升会对工业废水排放总量产生正向影响。技术水平和对外开放对工业废水排放总量的影响不显著,但对排放强度却有抑制作用;③经济集聚对工业废水排放总量和排放强度的影响存在单一门槛,当经济集聚度跨越门槛值后对工业废水排放总量和排放强度的抑制作用均有所减弱。最后,建议在促进经济集聚过程中应充分关注空间因素及其独特特征,针对工业废水减排可同步实施区域内针对性治理和跨区域协同治理的策略举措,切实推进长江经济带高质量发展。 相似文献
5.
运用考虑非期望产出的SBM模型,测度长江经济带沿线102个城市2004-2018年绿色创新效率,构建中介模型分析外商直接投资在环境规制对沿线城市绿色创新效率影响下的中介效应,并基于门槛回归模型考察环境规制在不同FDI发展水平下对城市绿色创新效率的影响机制.研究表明,长江经济带沿线城市的绿色创新效率存在空间非均衡性;加强环境规制对沿线城市绿色创新效率具有显著促进作用,FDI在其中具有部分中介作用;环境规制对长江经济带沿线城市绿色创新效率的影响基于FDI存在双门槛效应,呈现"N形"非线性关系. 相似文献
6.
运用考虑非期望产出的SBM模型,在测度长江经济带沿线102个城市2004-2018年绿色创新效率的基础上,构建中介效应模型实证分析外商直接投资在环境规制对绿色创新效率影响的中介效应,并基于门槛回归模型,综合考察环境规制在不同FDI发展水平下对长江经济带沿线城市绿色创新效率的影响机制。研究结果表明：(1)研究期内,长江经济带102个城市的绿色创新效率存在较大的空间非均衡性,长江上游和长江中游的绿色创新效率基本保持稳定,长江下游的平均绿色创新效率呈现出不断上升的趋势。(2)加强环境规制,对于绿色创新效率具有显著促进作用,外商直接投资在环境规制对城市绿色创新效率的影响中具有部分中介作用,政府加强环境规制可以在一定程度上有效限制污染型行业外商直接投资的流入,从而促进长江经济带沿线城市进一步提升城市绿色创新效率。(3)在不同FDI发展区间内,环境规制对长江经济带沿线城市绿色创新效率的影响方向并不相同,存在双门槛效应,跨过第一门槛值8.293后,环境规制对城市绿色创新效率由促进作用变为抑制作用,跨过第二门槛值11.695后,环境规制对城市绿色创新效率又再次变为促进作用。 相似文献
7.
为实现我国城市发展的绿色转变,以长江经济带37个城市为研究对象,基于超效率SBM模型和GML指数评价城市绿色创新效率及其时序动态演变规律,并运用空间杜宾模型检验不同区域效率的制约因素.研究表明:长江经济带城市绿色创新效率整体上升,下游、上游和中游从高到低依次排列,区域差距悬殊;中游地区技术进步优于上游地区,但技术效率有较大提升空间;整体上邻近城市绿色创新效率提高会对本城市产生正向溢出效应,但中游地区的溢出效应为负;整体上经济发展、产业升级和城市开放均促进绿色创新效率提升,环境规制与效率呈"U"型曲线关系,但在不同区域各因素的表现具有显著差异.并为长江经济带平衡环境保护和经济增长以及实现区域协同发展,从建设协调发展带、改进地方政策实施理念和继续推进对外开放等方面提出对策建议. 相似文献
8.
为推动我国工业绿色可持续发展，以长江经济带为对象，将环境规制与工业集聚同时纳入研究框架，构建动态面板模型和面板门槛模型测算108个城市2003—2017年的工业绿色经济效率，探究环境规制、工业集聚与工业绿色发展之间的关系以及区域空间异质性影响。结果表明：工业集聚与长江经济带工业绿色经济效率之间存在“U”型关系；环境规制在工业集聚对工业绿色发展的负向作用中具有负向调节效应；工业集聚对工业绿色发展的影响存在以环境规制为门槛的双重门槛效应，影响趋势随环境规制强度的加大呈现出负向影响逐渐减弱甚至由负转正的效果，且这种逆转效果在下游地区更为显著。由此，提出长江经济带打造世界级产业集群要引导工业合理布局和有序聚集，继续采取更严格的环境规制手段并注意配套结合，推动下游地区各类创新要素向中上游地区流动，以及在引进外资时提高环保准入门槛等发展建议。 相似文献
9.
长江经济带在中国区域发展布局中具有重要的战略地位,研究长江经济带分区及全局外向型经济的空间溢出效应既有利于提升上、中、下游地区的外向型经济发展水平,又能为长江经济带早日实现对外开放新格局提供借鉴。基于邻近关系、地理距离、经济引力模型的权重矩阵,构建空间计量模型,从全局和分区两个层面入手,探究2005—2017年长江经济带外向型经济的空间溢出效应。结果表明：①3种权重矩阵下,长江经济带外向型经济均表现出较强的空间集聚特征,但各市域外向型经济发展水平更倾向于受到相邻市域的影响。②从全局层面来看,长江经济带外向型经济具有显著的正向空间溢出效应,且第三产业比重提升是促进长江经济带外向型经济整体发展最显著的因素。③从分区层面看,上、中、下游地区外向型经济的主要影响因素不同。区域经济政策对上游地区外向型经济的提升作用最为显著;第三产业比重提升对中游地区外向型经济产生最积极的促进作用;交通连接度指数对下游地区的外向型经济产生最显著的正向影响。据此,提出促进长江经济带外向型经济发展的建议。 相似文献
10.
《中国科技论坛》2021,(1)
绿色发展与创新驱动的深度融合对推动长江经济带高质量发展具有重要意义。本文采用改进的DEA模型测度2004—2017年长江经济带沿线108个城市的创新绩效,并采用面板门槛模型,揭示长江经济带沿线城市污染排放(EP)、环境治理(GE)、人居环境(RE)等环境异质性因素对创新绩效的影响机制。结果表明:(1)研究期内,长江经济带上、中、下游地区城市的创新绩效整体上在波动中稳步提升,且存在较大的空间非均衡性;(2)污染排放对沿线城市创新绩效的影响呈现显著的双门槛特征,跨越第二门槛之后,污染排放对沿线城市的创新绩效产生一定的抑制作用;(3)环境治理对创新绩效的正向双门槛影响随着城市人均GDP的提高不断增强,而人居环境的正向单门槛影响随着城市人均GDP的提高不断下降。 相似文献
11.
A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
13.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
14.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
15.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
16.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
17.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
18.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献