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1.
基于2005—2018年中国内地285个地级市数据,对城市科技人才集聚与全要素生产率(简称“TFP”)进行测度分析,实证考察科技人才集聚对TFP的影响。结果表明:①城市科技人才集聚与TFP空间分异特征显著,但二者具有较强的时空一致性,即科技人才集聚特征显著的城市,其TFP也相对稳定;②城市科技人才集聚对TFP的影响呈倒U型,但研究期内大多数城市仍处于集聚效应占主导阶段,科技人才集聚通过提升城市技术进步水平促进TFP增长,而科技人才集聚对技术效率的影响呈倒U型;③不同类型城市科技人才集聚对其TFP影响的异质性显著,且适宜集聚区间也存在差异。省会城市及一、二线城市等优势特征显著的城市所能承受的科技人才集聚规模上限更高,有利于通过释放集聚红利促进TFP增长,而非省会城市、三线及以下城市等则拐点值较低。  相似文献   
2.
医药产业作为河北省重点发展的支柱产业之一,近年来发展形势不容乐观,正位于产业发展拐点之上。正定片区的建立释放了大量的红利,对于河北省医药产业的转型升级具有重要意义。本文在客观分析河北省医药行业发展现状的基础上提出了其存在的问题,并结合正定片区在医药方面的优势做出了有针对性的对策建议,助推河北省医药行业新发展。  相似文献   
3.
The introduction of automated vehicles (AVs) is a virtual certainty. Much less certain is the timing of their introduction and how rapid the transition to full automation will be. Various governments are already working to facilitate this shift by, for example, amending and elaborating regulations to support the introduction of AVs, or supporting tests in different urban environments. Meanwhile, urban and regional planners and decision-makers are still grappling with the uncertainties and differing opinions about the possible impacts of AVs on land-use changes and location choices, particularly in relation to the space available for vehicles, both moving (i.e. roadspace) and stationary (i.e. parking space). This paper uses a backcasting approach to identify critical policy decisions and measures to be taken before the implementation of AVs, so as to achieve a more desirable, attractive and high-quality city. These policy measures primarily relate to the reuse and reallocation of parking and roadspace. Two strategic decisions are found to be essential to meet the major goals of sustainable and liveable cities: a clear commitment to a shared mobility and the delimitation of Core Attractive Mixed-use Spaces (CAMS). In order to deliver these desired urbanisation patterns, a set of three policy paths, involving eight policy packages, is proposed for the next 20–30 years. This article provides urban and regional decision-makers with examples of interventions that can be implemented beyond and during the implementation of AVs.  相似文献   
4.
Deliberations about how to govern complex problems of urban health and wellbeing sustainably have often been implicitly biased by ideas such as being ‘human-scale’ or ‘people-centered.’ With increasing urban populations and increasing urban system interconnectivity, many cities have transformed into city regions or clusters, and the external effects of urban growth are carried mainly by the marginalized and the environment putting urban health increasingly at risk. Here we address the question of why human societies have not been better at collectively adapting to the challenges of urbanization and global environmental change? We build a theoretical framework of multi-level selection, complex systems evolution, and governance, following which we then present ‘human-scale’ and ‘people-centered’ ideas of urban development as expressions of two types of socio-political organization with different degrees of self-organization. We found several reasons for which the maladies of current urban development emerged and the seeming inability to resolve them. First, urban systems became increasingly interconnected and evolved into ultrasocial superorganisms, displaying preference to sustain themselves as a whole rather than their subordinates. Second, the difference in scaling effects between the biological and the social network contributed to the mismatch between rapid urban growth and slow adaptation. Furthermore, institutions of decreased variety reinforce themselves and become dominant, creating a positive feedback mechanism and promoting invasive and exploitative exponential growth, but they also reduce the creativity and resilience of urban systems. We also found that both the “human-scale” and the “people-centered” approaches acknowledge the exponential growth and decreasing variety in urban systems, and advocate for correcting the mismatches. To incorporate people's needs and values for long-term, truly sustainable urban health governance, we recommend combining the self-organizing, evolutionary feature of “human-scale” and the coordinative, political feature of “people-centeredness.”  相似文献   
5.
在构建以国内大循环为主体、国内国际双循环相互促进的新发展格局下,高效协同的区域创新体系有助于将粤港澳大湾区三地建设成为具有全球影响力的科技创新中心。通过构建创新生态系统综合评价指标体系,采用耦合协调模型和空间计量模型,实证检验大湾区10个城市2007-2019年创新生态系统内部耦合协调水平、时空跃迁特征以及收敛性。研究发现,大湾区整体及各城市耦合协调度呈上升趋势,基本实现从失调衰退区到协调过渡区的转化,具体可划分为4个等级层次;大湾区创新生态系统协调耦合度存在显著的绝对β与条件β收敛趋势,即最终收敛于同一稳态水平,且城市间差距逐渐缩小。其中,经济发展水平、对外交流水平、人力资本水平对创新生态系统协调耦合度起显著正向作用。  相似文献   
6.
This study provides evidence for the impact of an urban growth boundary (UGB) on house prices. The study employs a two-stage quantile spatial regression method on a dataset that inventories sales transactions of single-family houses within two miles of either side of the eastern boundary of the primary UGB in King County, Washington. The results show that while the UGB decreases house prices across the entire house price spectrum, the impact is uneven; it is most pronounced for houses in the 5th to 8th decile of prices. These findings should encourage policy makers to adopt sub-housing-market-level policy approaches to address UGB and other urban and regional development policies’ potential impacts on house prices.  相似文献   
7.
李政  杨思莹 《南方经济》2019,38(12):49-67
文章基于2003年至2016年我国215个城市面板数据,运用双重差分模型、空间双重差分模型和分位数回归模型等方法,实证检验了国家高新区对城市创新水平的影响及其空间异质性特征。研究结果表明,国家高新区建设显著提升了城市创新水平,并且高新区设立带动的城市投资集聚是推动城市创新水平提升的重要原因。空间双重差分结果表明,国家高新区对城市创新水平的提升作用并非源于其对周边城市创新资源的掠夺,相反高新区设立对周边城市和省内城市均产生了显著的溢出效应,提升了本省城市和周边外省城市创新水平。此外,国家高新区对城市创新水平的影响具有空间异质性特征,在省会城市、直辖市和副省级城市,高新区对城市创新水平的影响并不显著,而能够显著提升一般地级市创新水平;随着城市创新水平的提升,高新区建设对城市创新水平的促进作用呈现出先增强、后减弱直至不再显著的非对称"倒V型"变化特征。但是研究也发现,国家高新区对城市创新水平影响的区位异质性并不显著,高新区对东部地区和中西部地区城市创新水平提升均具有显著的促进作用。  相似文献   
8.
Using a sample of Chinese firms, we examine stock market reaction to firms that announce a change in their product lines to those related to COVID-19 management (medical masks and ventilators, among others). We find the market reacts positively to the announcements. In addition, when a firm ordinarily has a large share of export sales, the stock market reaction is more salient, indicating that export sales provide a certification effect that positively signals investors. Additional analysis on moderating effects suggest that, conditional on foreign sales, prior experience with medical product lines or less uncertainty about supply availability enhances the cumulative announcement returns (CARs), while the adverse impact of firm size on CAR magnifies.  相似文献   
9.
基于“互联网+”大背景,跨界创新成为实现突破性技术创新的重要形式。通过现有文献分析,构建了跨界创新在突破性技术创新模糊前端的作用模型,并运用案例研究法,以无人驾驶汽车为例对模型进行释义。研究表明,跨界创新在突破性技术创新模糊前端起到重要作用,跨界创新可分为跨界搜索与跨界合作,跨界搜索有助于创意搜集和创意筛选,识别突破性技术创新机会;跨界合作有助于提升研发效率和成功率;跨界搜索与跨界合作相辅相成,共同致力于突破性技术研发成功。  相似文献   
10.
Hong Kong's retrocession to Chinese sovereignty in 1997 initiated intense interest in cultural heritage on the part of divergently positioned actors, including activists, the state, and entrepreneurs. Heritage walking tours have proliferated, providing a wide range of examples suitable for comparison. This article develops a typology of heritage trails and tours in order to consider how they are situated in relation to the tourist economy and local context. Theoretically it builds on insights in new walking studies and debates in tourism and heritage studies on the ‘tourist-local divide.’ The article relies on qualitative research conducted in Hong Kong, including participant observation and interviews, and a review of various secondary sources. The typology distinguishes between government-generated, market-oriented, and community-based heritage walks. Three key issues are discussed: the ways that tours and trails develop, how they engage with official and unofficial heritage places, and how they reference urban issues including state-led urban renewal and redevelopment. The article argues that, while walking in general is a format that is suited to both tourist and local visitor engagement, some trails and tours reinforce dominant narratives of heritage and urban space, while others challenge them.  相似文献   
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