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1.
The COVID-19 pandemic has had a great impact on food shopping behavior. However, changes in food shopping behavior and related decision-making mechanisms remain unexplored. This study conducted a face-to-face questionnaire survey with 900 residents in three communities in Haidian, Beijing, China, to analyze food shopping behavior during the periods of pre-lockdown, lockdown (January–March 2020), and post-lockdown. Our results indicated that the preference for fresh food e-commerce shopping was accelerated by the lockdown with the usage rate increasing by 48%; the wet markets were seriously hit by the lockdown policy and had not fully recovered by the post-lockdown period (with a 75% reduction in the usage rate during lockdown). The psychological mechanisms of changes in food shopping behavior revealed that the context (e.g., community facilities) and the perceived risk of COVID-19 were two significant factors impacting the four shopping choices investigated. Specifically, the context factors affected behavior directly for supermarkets and convenience stores and indirectly for e-commerce and wet markets. The findings are expected to help in guiding emergency responses during a future pandemic as well as the long-term construction of food supply facilities.  相似文献   
2.
基于253家浙江省众创空间的微观数据,文章在运用连续距离的测度方法测算众创空间集聚水平的基础上,采用零膨胀负二项回归等方法实证分析众创空间集聚的影响机制。研究发现,众创空间的地理分布存在显著的区域差异,主要分布在杭州和宁波市辖区,选址具有明显的集聚特征。回归结果显示,区域创新能力和生态环境均对众创空间的地理集聚具有促进作用,但两者之间存在明显的替代效应;尽管不能直接促进众创空间的集聚,政策引导与创新能力之间具有较显著的互补效应。据此,文章从培育创新能力和优化创新激励等方面提出了政策建议。  相似文献   
3.
This article explores urban agriculture in Cape Town and its organisational forms. Based on a literature review of peer-reviewed articles and grey literature, it examines the state of linkages among urban farmers and various supporting organisations of urban agriculture. Moreover, it examines the coordination of activities among key supporting organisations. By analysing the roles of state and non-state actors and linkages, the article discusses implications for the development of urban agriculture. This article suggests that a lack of effective coordination of initiatives among supporting actors presents a significant pitfall in the development of urban agriculture. Furthermore, the failure of farmers to self-organise is identified as equally detrimental. Therefore, it calls for improved synergies between state and non-state actors involved to ensure that the gains of urban agriculture are enhanced.  相似文献   
4.
王文佳  熊涓 《企业经济》2020,(1):108-118
通过空间计量模型考察生产性服务业发展模式与制造业集聚的空间溢出效应后发现:生产性服务业专业化水平及多样化水平与制造业集聚呈倒U型关系,同时城市化水平会对服务业发展模式与制造业集聚关系产生影响。分区域模型研究发现,生产性服务业对制造业全要素生产率影响因区域经济发展水平、产业层次、要素禀赋等因素有所差异,东部地区制造业全要素生产率与生产性服务业呈线性关系,适合选择多样化发展模式;中部地区呈倒U型关系,现阶段中部地区生产性服务业更适合选择多样化发展模式;西部地区生产性服务业发展水平与制造业全要素生产率呈正U型关系,生产性服务业专业化和多样化发展都将促进制造业全要素生产率提升。  相似文献   
5.
基于引力模型,结合社会网络分析法的凝聚子群分析,对31个省(区、市)的创新产出空间联系进行探究,研究发现:我国省域创新产出空间联系主要集中于京津冀和长三角一带,呈现出严重的分布不均状况,具有较强的区域集中性和空间依赖性;北京、天津、上海、浙江、江苏作为区域创新产出引力较强的节点省(区、市),对周边区域的创新产出具有较强的辐射作用;总体来看,省域创新产出空间联系并没有形成贯穿东西南北的交叉网状结构,中心省(区、市)数量较少且分布不均,辐射范围有限。基于此,提出加大区域创新投入、减少区域创新产出联系的政策性障碍、营造区域创新产出联系的良好环境等政策建议。  相似文献   
6.
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   
7.
金环  于立宏 《南方经济》2021,40(12):21-36
当前,数字经济蓬勃发展,数据已成为除劳动、土地和资本等传统生产要素之外的新要素,能否依托数字经济发展赋能城市创新?文章在对数字经济的概念和内涵进行基本界定后,借助微观大数据构造的"互联网+数字经济"指数,实证分析了2015-2018年中国283个地区数字经济发展对城市创新及创新差距的影响。研究结果显示,数字经济发展能够显著促进城市创新水平提升。其中,人力资本集聚效应和创业活力增强效应是数字经济赋能城市创新的两条重要路径。在替换被解释变量、消除样本选择偏差、选择分位数回归,以及创新性地采用各地级市市长过去修习的专业作为历史工具变量检验后,这一结论依然稳健成立。进一步空间杜宾效应分析表明,数字经济发展具有显著的空间溢出效应特征,不仅促进了本地区创新水平提升,而且对相邻地区的创新产出也产生了实质性影响,有利于缩小区域创新差距,实现区域创新收敛。此外,相较于实用新型专利和外观设计专利,数字经济发展对城市发明专利的影响更显著,说明数字经济发展推动的创新是真正意义上的质量创新而非策略创新。文章为评估数字经济发展的影响效果提供了理论依据和经验支撑,也为理性看待数字经济、防止出现数字鸿沟,实现区域创新均衡发展提供了有益启示。  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.
产业集聚和市场集中是影响区域创新能力的重要因素。本文考察了京津冀、长三角两大经济圈制造业产业集聚与市场集中对区域技术创新能力的作用。实证分析结果表明:两大经济圈制造业集聚与市场集中均在一定程度上促进了区域创新能力的提升,但由于两大区域体制机制条件、创新环境、产业组织形态等不同,制造业产业集聚影响区域技术创新的程度、特征与路径也存在一定差别。两大经济圈应采取差异化集群发展方式,加快推进制造业集群升级,特别是应抢抓第四次工业革命发展机遇,提升制造业智能化水平,提升区域创新能力水平。  相似文献   
10.
Bogotá and the 17 neighboring municipalities make up one of the biggest metropolitan areas in Latin America. However, despite strong functional interactions within the area, there is no official government body at this level in charge of coordinating authorities and providing solutions to the wide variety of issues arising in the regional urban land system. Aiming at providing an insight on future land-use developments linked to new transport infrastructures and at offering a tool to support territorial decision-making, this paper presents a cellular automata-based (CA) model based in Metronamica® software, that allows testing different scenarios based on potential land-use policies, environmental suitability and transport alternatives.There has not been, so far, an urban planning tool that accounts for the complexities of this region. CA-based land-use simulations constitute a useful approach to understanding the impacts of urban planning policies and regulations. This tool can help to improve inter-territorial and inter-institutional coordination, which through planning and management policies seek a spatially integrated development, with a long-term perspective.The CA-based model proposed was calibrated to reproduce land-use changes between 2007 and 2016 using different methods and indicators. The model was used to simulate and analyze eight scenarios with different policy directions of transport infrastructure in the future of the region. The results of the simulations reflect the dynamics of territorial occupation. The calibration indices in the experiment indicate a high degree of suitability for the CA Bogotá model, proving its effectiveness and potential as a useful tool for decision-making. The results show that occupation scenarios with restricted developable zones within the city, tend to have the greater dispersion rate in the study area, compared to scenarios where land development plans are promoted in Bogotá, which representing a more compact development.  相似文献   
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