Structural Characteristics and Influencing Factors of Carbon Emission Spatial Association Network:A Case Study of Yangtze River Delta City Cluster,China

City cluster is an effective platform for encouraging regionally coordinated development.Coordinated reduction of carbon emissions within city cluster via the spatial association network between cities can help coordinate the regional carbon emission management,realize sustainable development,and assist China in achieving the carbon peaking and carbon neutrality goals.This paper applies the improved gravity model and social network analysis(SNA)to the study of spatial correlation of carbon emissions in city clusters and analyzes the structural characteristics of the spatial correlation network of carbon emissions in the Yangtze River Delta(YRD)city cluster in China and its influencing factors.The results demonstrate that:1)the spatial association of carbon emissions in the YRD city cluster exhibits a typical and complex multi-threaded network structure.The network association number and density show an upward trend,indicating closer spatial association between cities,but their values remain generally low.Meanwhile,the network hierarchy and network efficiency show a downward trend but remain high.2)The spatial association network of carbon emissions in the YRD city cluster shows an obvious‘core-edge’distribution pattern.The network is centered around Shanghai,Suzhou and Wuxi,all of which play the role of‘bridges’,while cities such as Zhoushan,Ma'anshan,Tongling and other cities characterized by the remote location,single transportation mode or lower economic level are positioned at the edge of the network.3)Geographic proximity,varying levels of economic development,different industrial structures,degrees of urbanization,levels of technological innovation,energy intensities and environmental regulation are important influencing factors on the spatial association of within the YRD city cluster.Finally,policy implications are provided from four aspects:government macro-control and market mechanism guidance,structural characteristics of the‘core-edge’network,reconfiguration and optimization of the spatial layout of the YRD city cluster,and the application of advanced technologies.

Characteristics of atmospheric particles and heavy metals in winter in Chang-Zhu-Tan city clusters, China

To understand the pollution characteristics of atmospheric particles and heavy metals in winter in Chang-Zhu-Tan city clusters, China, total suspended particulate （TSP） and PMI0 samples were collected in cities of Changsha, Zhuzhou and Xiangtan from December 2011 to January 2012, and heavy metals of Cd, Pb, Cr, and As were analyzed. It shows that the average TSP concentration in Changsha, Zhuzhou and Xiangtan were （183 ± 73）, （201± 84） and （190 ±66） μg/m3 respectively, and the average PM10 were （171 ± 82）, （178 ± 65） and （179 ± 55） μg/m3 respectively. The lowest TSP and PM10 concentrations occurred at the background Shaping site of Changsha. The average ratio of p（PM10）/p（TSP） was 91.9%, ranging from 81.3% to 98.9%. Concerning heavy metals, in TSP samples, the concentration of Cr, As, Cd and Pb were 28.8-56.5, 18.1-76.3, 3.9-26.1 and 148.0-460.9 ng/m3, respectively, while in PMI0 samples, were 16.4--42.1, 15.5-67.9, 3.3-22.2 and 127.9-389.3 ng/m3, respectively. The enrichment factor of Cd was the highest, followed by Pb and As, while that of Cr was the lowest.

Spatial and Temporal Distribution of PM_(2.5) Pollution and Control Strategy in the Chang-Zhu-Tan City Cluster

Utilizing the initial hourly monitoring data of PM_(2.5) concentrations at 23 monitoring sites across the Chang-Zhu-Tan city cluster between January 2013 and February 2014 that released in Real-time Air Quality Reporting System in Hunan Province, this paper draws diagrams and analyzes the change rule of the pollutants concentration over time. In addition, this paper studies the regional distribution of PM_(2.5) seasonal pollution in the vicinity of the monitoring sites using Arc GIS geographic information system with the Kriging interpolation method.On this basis, this paper puts forward some effective control strategies to cope with regional PM_(2.5) pollution combined with the information of industry distribution and development status in the Chang-Zhu-Tan city cluster.

Comprehensive Measurement for Carrying Capacity of Resources and Environment of City Clusters in Central China

Studying the carrying capacity of resources and environment of city clusters in the central China has important practical guidance significance for promoting the healthy, sustainable and stable development of this region. According to their influencing factors and reciprocity mechanism, using system dynamics approaches, this paper built a SD model for measuring the carrying capacity of resources and environment of the city clusters in the central China, and through setting different development models, the comprehensive measurement analysis on the carrying capacity was carried out. The results show that the model of promoting socio-economic development under the protection of resources and environment is the optimal model for promoting the harmony development of resources, environment, society and economy in the city clusters. According to this model, the optimum population scale of the city clusters in 2020 is 42.80×106 persons, and the moderate economic development scale is 22.055×1012 yuan (RMB). In 1996-2020, the carrying capacity of resources and environment in the city clusters took on obvious phase-change characteristics. During the studied period, it is basically at the initial development stage, and will come through the development process from slow development to speedup development.

Issues of Eco-agricultural Industrialization for Big Qinling Eco-city Cluster

Firstly,the necessities of ecological agriculture development in Big Qinling Eco-city Cluster were discussed.Then,condition endowment of eco-agricultural industrialization in Big Qinling Eco-city Cluster was analyzed from the aspects of basic conditions and differential endowment of eco-agricultural industrialization.Finally,specific forms and functional orientation of eco-agriculture were pointed out.Countermeasures for the eco-agricultural industrialization in Big Qinling Eco-city Cluster were put forward.Firstly,the government guidance and the media publicity should be strengthened.Secondly,financial support for the eco-agricultural industrialization in Big Qinling Eco-city Cluster should be enhanced.Thirdly,branding strategies of eco-agricultural products in Big Qinling Eco-city Cluster should be implemented as soon as possible.

Order Exponential Evaluation Model for Road Traffic Safety in City Clusters

This study presents an order exponential model for estimating road traffic safety in city clusters.The proposed model introduces the traffic flow intrinsic properties and uses the characteristics and regular patterns of traffic development to identify road traffic safety levels in city clusters.Additionally,an evaluation index system of city cluster road traffic safety was constructed based on the spatial and temporal distribution.Then Order Exponential Evaluation Model(OEEM),a comprehensive model using order exponent function for road traffic safety evaluation,was put forward,which considers the main characteristics and the generation process of traffic accidents.The model effectively controlled the unsafe behavior of the traffic system.It could define the levels of city cluster road traffic safety and dynamically detect road safety risk.The proposed model was verified with statistical data from three Chinese city clusters by comparing the common model for road traffic safety with an ideal model.The results indicate that the order exponent approach undertaken in this study can be extended and applied to other research topics and fields.

Evaluation of carrying capacity of city clusters in China with the example of the Blue Economic Zone of Shandong Peninsula

The conflict between city development and urban carrying capacity is getting ever prominent.In order to study and predict the restriction factors and prominent problems in the development of the Shandong Peninsula Blue Economic Zone as well as promote the transfer of economic development pattern in this region,this study starts from four single factor carrying capacity indicators of water,earth,transportation and environment in the city and its comprehensive carrying capacity indicator,evaluates and analyzes its carrying capacity and then papooses policy suggestions for improving its carrying capacity.

Research on the Joint Development of Cities of Guangdong-Hong Kong-Macao Greater Bay Area: A Case Study of Foshan City

Promoting the construction of Guangdong-Hong Kong-Macao Greater Bay Area is a major policy decision and national strategy made by the central government of China,which significantly supports the Belt and Road Initiative and maintains the long-term prosperity for the whole country.As an important part of the Guangdong-Hong Kong-Macao Greater Bay Area,Foshan needs to find its own position and direction in order to accelerate the joint development with other cities through five measures.

Development Status and Policy Path of Cultivating Marine Bio-industry Cluster in Zhanjiang City

Cultivating the marine bio-industry cluster is a key industrial strategy for Zhanjiang to seize the manufacturing position of Guangdong's marine economy. By deconstructing the overall scale,characteristics and industrial composition of marine bio-industry cluster and the development status of the industrial parks and bases in Zhanjiang,the resource misallocation coefficient was used to analyze the problems in the marine bio-industry cluster and the resource allocation in Zhanjiang. It is found that in the cultivation of the marine bio-industry cluster in Zhanjiang,the leading effect of leading enterprises needs to be upgraded,the key technologies needs to be broken,the scientific and technological service system needs to be improved,and policy support needs to be strengthened. Moreover,there are serious resource misallocation and high efficiency losses. By optimizing resource allocation,the healthy development of cultivation of marine bio-industry cluster in Zhanjiang will be promoted. To this end,the policy paths that the government can implement are as follows: improving the market access system to appropriately guide medium and small-sized marine enterprises to enter the marine bio-industry,inspiring the marine bio-industry market demand with the industrialization of innovation results as the guide,improving the legal guarantee system to create an innovative atmosphere for the marine bio-industry,and promoting the deepening of the division of labor in the industrial parks.

金融要素集聚的绿色创新效应:空间关联特征与城市群异质性

区域绿色技术创新体系建设是经济绿色转型的重要基础,而金融要素空间集聚则充当着科技创新活动的重要加速器。现有文献围绕着金融要素集聚和绿色技术创新两条主线展开广泛讨论,也关注到金融要素集聚所内生的绿色创新效应,但较少基于城市群这一新时期区域协同发展的新型空间载体,系统考察两者的空间关联效应及其区域异质性特征。因此,选取国内十大代表性城市群,对其内部金融要素集聚和绿色技术创新的时空演变轨迹和空间关联异质性进行多维度诊断。研究发现:第一,金融要素集聚有助于通过各种空间效应加速城市群内部的绿色金融发展,进而正向驱动区域绿色技术创新水平的提升;第二,城市群范围内的金融要素集聚不仅会对区域绿色技术创新产生明显的本地促进效应,也会同时形成显著的空间溢出效果;第三,金融要素集聚对于绿色技术创新的空间效应还会受到城市群金融集聚模式、行政层级特征、经济发展状况等因素制约。有鉴于此,区域协同发展过程中,应围绕城市群发展定位构建差异化的金融要素集聚模式,因之打造契合于不同城市群现实约束的绿色金融服务体系和绿色技术创新体系;同时深度挖掘金融要素集聚对于绿色金融发展和绿色技术创新的空间传导效应及其异质性特征,推动金融改革和绿色发展的有效空间互动。

城市群规划实施效果评估研究——以长株潭城市群为例

长株潭城市群经济发展对于湖南省以及中国中西部地区的发展至关重要,且该城市群规划实施的效果对其他城市群有重要借鉴意义。基于此,文章根据2000-2017年地级市面板数据,采用合成控制法,评估长株潭城市群规划实施后对城镇化和环境质量的影响。评估分析表明,长株潭城市群规划的实施推动了城市群城乡融合,在一定程度上促进了城镇化的进程,但对环境造成了一定的负面影响,其原因在于长株潭城市群内城市之间的非均衡发展。因此,城市群应着眼于制定合理规划,促进城市均衡发展,重点落实城乡融合和生态文明;各级政府应加强公共治理,强化监督和治理责任,以更好地实现城市群规划的既定目标。

影响城市交通发展的基础问题研究

中国城市的发展阶段和趋势特征与社会主义市场经济体制改革的进程息息相关,不同阶段经济社会、城乡建设、法律制度、行政管理、财税制度等各方面的变革都对城市交通发展产生深刻影响。因此,研究新时期城市交通的发展模式必须遵循国家政策和改革措施。通过梳理改革开放以来的变革进程,总结当前中国发展呈现的一系列阶段性新特征,包括社会主要矛盾转变为人民日益增长的美好生活需要和不平衡不充分的发展之间的矛盾,经济体制改革强调推动有效市场和有为政府的更好结合,法律制度规定将城市交通问题的事权和财权划分为地方事务,城市发展进入区域化、数字化、低碳化发展新阶段等。基于这些特征,要求坚持城市政府的主体地位,以改革促进城市交通发展,支撑现代化都市圈培育,面向居民需求提升城市可持续发展能力和竞争力。

中国省会航空节点城市复杂时空系统协调度变化及空间特征分析

航空运输业提升了城市系统的吸引力并激发新的交通需求,引导城市经济和空间结构快速演进。本文构建了包含经济、规模、外贸、科技、社会、环境、航空等要素在内的城市复杂时空系统指标体系,对中国省会航空节点城市及其构成的7个空管区的复杂时空系统发展的协调程度变化情况及时空聚类特征、空间溢出效应进行了分析。研究发现:2001—2019年,中国31个省会(首府、直辖市)航空节点城市在复杂时空系统发展过程中呈现了或分散、或集中的趋势特征,南方城市在研究末期的协调程度表现更好。7个空管区中,华北区协调度最高,新疆区、西北区、华东区、中南区的协调度水平发展增速较快,航空系统的平均协调度最高。各航空节点城市复杂时空系统协调度的时空聚类模式存在空间分异特征与聚类特征,航空系统在空管区的聚类优势最为突出,经济系统在空管区聚类辐射范围最大。航空、规模、科技与环境系统均表现了正向直接空间溢出效应,经济与科技系统表现了正向间接空间溢出效应。通过全面分析航空节点城市及空管区的复杂时空系统协调度变化,精准判定了航空节点城市多指标系统在区域发展过程中的影响程度及时空分布异质性,对拓展航空地理研究及促进航空节点城市高质量综合发展提供理论依据。

城市休闲产业聚类模式APM算法模型开发与校验

城市休闲相关产业的高质量发展对当前我国城市消费升级以及人居环境质量提升具有重要现实意义。但是,现有研究未能精准地捕捉海量广域分布的城市休闲产业的基本空间分布规律与结构,而已有的空间聚类算法较多适用于城市用地分析,未能很好地适用于离散分布的城市休闲产业研究。为此,文章基于空间兴趣点数据,开发距离通达值及空间集群中心点等算法,构建城市休闲旅游产业聚类模式空间算法模型(APM)。在以广州为例的研究中,APM模型捕捉出3170个以500 m步行生活圈为范围的城市休闲产业集群,校验了APM模型的科学性与应用价值。整体上,APM算法可以较好地捕捉城市休闲业态集群的空间结构,清晰识别城市休闲产业空间冷、热点分布的基本结构,由其捕捉行程的聚类边界与实际道路和建筑走向、水系边界、区域范围等重合度高,聚类集群符合实际情况,具备可信度与有效性。该研究是休闲产业集聚机制研究的一次方法创新,在算法精度、实际应用、可视化效率上均做出了创新性推进。与Fishnet方法相比,可以更科学精准地识别城市内部多个休闲消费商圈的边界,实现了高效率的城市休闲产业集群捕捉;与同位模型相比,可以呈现多类别的城市休闲业态结构,突破了现有研究只能捕捉两类业态组团的局限。

黄河流域乡村集群的空间协同发展路径——以黄河滨州段为例

立足于黄河流域生态保护和高质量发展、乡村振兴国家战略在山东的地域性实践背景,基于对黄河流域乡村集群的空间协同发展路径研究,阐释乡村集群的概念并归纳沿黄乡村集群特征,从黄河流域乡村的发展壁垒入手,将乡村集群类型划分为城乡融合型、带状集聚型、组团提升型等3种集群空间模式,提出统筹体系架构与空间优化两层面的协同路径。随后,以《滨州市黄河沿岸国土空间规划》为例,以229个村庄为样本,构建由城乡融合示范区、特色集聚段、门户提升段构成的“一区三段”乡村集群空间格局,提出“尺度嵌合、显隐结合、城乡融合”的空间协同路径,以及空间多尺度的分类传导和规划多嵌套的分级传导体系,以期为黄河流域乡村高质量发展提供可参考的路径模式。

产品差异化和市场开放度对城市群空间结构的影响研究

城市群是提高地区经济增长和深入实施区域协调发展战略过程中的重要载体。本文尝试结合“新”新经济地理学模型和基于agent计算经济学对多重异质性下城市差异化对企业和人口的空间演化影响进行研究,建立了一个企业生产效率与规模、居民工资等多重异质性的两区域空间经济模型对城市间人口和企业迁移进行动态模拟以研究空间经济演化过程。结果表明:(1)无论是否存在市场进入和退出机制,小城市内部工业产品的差异性越大,越有利于企业和人口向小城市迁移,企业和人口倾向于分散。但是存在市场机制能提高城市内产品差异化对人口和企业迁移的吸引力。(2)城市群中小城市要更多的企业和人口,需要继续鼓励创新生产差异化产品,使城市内的产品更加多样化和差异化。(3)为了使城市内产品差异化发挥更大的作用,整个地区需要更加健全企业进入和退出的市场机制,使得有利可图的资本可以进入市场,同时亏损的企业能够退出市场或者转型升级和改制。

城市群型自创区创新共同体的建构基础与策略

创新共同体作为促进跨区域创新体系建设的有效途径,已成为城市群型自创区引领区域均衡发展和跨界协同创新的重要模式,其建构基础决定着自创区的创新路径选择与突破重点。结合城市群型自创区创新共同体的基本内涵与运行结构,设计涵盖自主创新力、协同配置力、效益贡献力和国际竞争力的“四力”评价体系,运用全局熵值法和耦合协调度模型测度我国8个城市群型自创区41个核心园区的“四力”耦合协调水平。结果表明:核心园区“四力”耦合协调水平整体呈结构稳定的偏态分布,板块间差异显著且趋势向好;自创区“四力”两极分化且优势各异。随后基于Dagum基尼系数揭示创新共同体建构基础的组内和组间差异,并对差异性溯源分析。组内差异显示:覆盖核心园区越多,协同创新难度越大;核心园区非均衡异化,差异性变动反差明显。组间差异显示:创新共同体建构基础表现出奋力争先、震荡纠缠、低速稳健、成长禁锢4种类型。基于此,从创新动力、协同配置、效益输出、国际竞争等方面提出创新共同体建构策略,以期为打造高质量紧密型创新生态圈提供参考。

中国智慧城市建设研究热点及发展趋势分析

智慧城市是提升城市管理成效和改善市民生活质量的重要手段之一。为深入明晰当前我国智慧城市建设研究现状,追溯探讨智慧城市建设的研究热点和发展趋势,运用CiteSpace软件,对2009~2023年间中国知网收录的500篇代表性研究文献进行学科分布、关键词聚类等可视化分析。结果显示:(1)智慧城市建设形成了战略性新兴产业研究、数字化构成、技术创新与战略规划三大类群主题;(2)我国的智慧城市建设领域演进可归纳为积极探索期、战略攻坚期和创新发展期三个阶段。分析结果将为我国智慧城市建设的高速发展提供决策参考依据。

社区尺度斜入射波场下场地-建筑群耦合作用模拟方法

场地-城市相互作用(site-city interaction,SCI)效应会显著改变场地地震波场分布及建筑反应,基于SCI效应理论计算研究方法的发展现状,发挥谱元(spectral element,SE)法可快速高效求解三维地震波场传播和多自由度(multi-degree of freedom,MDOF)模型计算量小且可同时模拟大量建筑的优势,同时,结合频率波数域(frequency wave number analysis,FK)方法,以等效地震荷载的方式施加地震波场,建立了FK-SE-MDOF耦合方法,实现了SE-MDOF耦合模型中多种波型(P波、SV波和SH波)的斜入射输入,解决了当前三维SCI效应研究方法中未能同时考虑建筑非线性、频谱特性、地震波波型及入射角度影响的问题。首先对方法原理进行了介绍;然后,通过与振动台试验的对比,验证了方法的正确性;进而,采用该方法建立理想场地-城市建筑群相互作用耦合模型,主要探讨了入射角度和地震波波型对SCI效应的影响,得到了一些有益结论。该方法较为真实地反映SCI效应影响的同时,可反映建筑基础轮廓对地震波场的影响,适用于需考虑建筑轮廓信息的社区尺度SCI效应研究,可为城市规划、抗震设计、风险评估以及震后救援等工作提供定量指导。

新乡市智能装备制造业存在的问题及竞争力提升对策研究

新乡市是河南省四大智能装备产业基地之一,但存在转型升级任务艰巨、集聚集群程度不高、小微企业多而不强、高端技术人才不足等问题。结合产业集群和技术创新产业升级理论,从加大支持力度、强化政策支持组织保障,坚持创新驱动、提升企业核心竞争能力,优化产业布局,推进产业集聚集群发展,加强人才保障、加快吸引高端人才落户,提升品牌影响力、打造智能装备制造名片等五个方面提出了提升新乡市智能装备制造业竞争力的对策。