Stability of Spatial Structure of Urban Agglomeration in China Based on Central Place Theory

This paper brings forward the concept of stability of the spatial structure of urban agglomeration(UA)based on Central Place Theory by introducing centrality index and fractal theory.Before assessment,K=4 is selected as parameter to calculate centrality index and fractal dimension(K represents the quantitive relationship between city and the counties in Central Place Theory),and then found the number of nodes,the type of spatial structure,the spatial al-location of nodes with different hierarchy affecting the stability of spatial structure.According to spatial contact direction and the level of stability,UAs in China are classified into five types.Finally,it is posed as a further question that how to use hierarchical relation K=6 and K=7 in central place system to coordinate with the assessment of stability of spatial structure is brought forward.

Spatial Structure of Central Places in Jilin Central Urban Agglomeration, Jilin Province, China

Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China and the structural characteristics of each tier: 1) the 1st tier central place, Changchun Proper(not including Shuangyang District), provides the most service functions and has the most stable primate position; 2) the 2nd tier central places, Jilin Proper, Siping Proper, Liaoyuan Proper and Songyuan Proper have unclear statuses and do not provide certain functions; 3) the 3rd tier central places comprise 23 county-level cities, counties and urban districts(including Shuangyang District of Changchun), exhibiting a dense spatial structure that agrees with theory; 4) the 4th tier contains the largest number of central places(248 designated towns), but they are loosely distributed. In this study, a spatial image of the JCUA was created, based on vectorized data of the urban settlement distribution, which was then modified and abstracted to create a hexagonal network covering the JCUA. Compared to the traditional central place model, the modified spatial image conforms to the K = 3 principle. In reality, however, the growth of some 3rd tier central places should be increased with the cities being upgraded to the 2nd tier so as to overcome that tier′s functional deficiency. The loose distribution in the 4th tier should also be changed. This apparent anomaly can be explained by the fact that the classic hexagon model used to describe the way market areas layout does not exist in the real world. However, this should not be viewed as an obstacle to using central place theory. If its assumptions are properly applied, it can still assist research into the spatial structure of regions.

SOME EMPIRICAL EXAMPLES OF CENTRAL PLACE MODEL IN CHINA'S RURAL AND URBAN STUDIES

At the beginning of the 1980s, the Central Place Theory(CPT) was introduced into China from the West. The authors of this article are the initiators of applying this model to China’s urban and regional planning as well as to the allocation of commercial activities. Since the commodity economy has been developing in China for thousands of years,most of the areas in eastern plains and inland basins of the country show the spatial structure of typical central places scene. During some six years, the authors participatd in a lot of rural, urban and regional planning projects in which the spatial phenomena and relevant internal mechanism proved this medel and its deformation. This paper gives only a few examples of the application of CPT in China. 1. The distribution of rural markets: the empirical study is based mainly on the situation in Shengfang Town and its vicinal area, 2. The spatial combination of urban Systems; problems about city allocation in North China are emphasized, 3. Commercial centres in city and the networks: a crucial study on commercial distribution of the metropolis Beijing is done by using the central place model.

An Overall Urban System: Integrating Central Place Theory and Urban Network Idea in the Greater Pearl River Delta of China

Following a half century of popularity, central place theory experienced 20 years of neglect when the new urban system theory of network modeling gained attention at the beginning of the 1990s. However, central place theory remains valid, and it seems there has been a reemergence with it. Using the Greater Pearl River Delta (Greater PRD) as an experimental study region, this paper intends to present an empirical study that validates central place theory and shows that it can be integrated into an overall regional urban system. The study uses the compound Central Place Importance (CPI) to evaluate whether there is a hierarchy among the urban centers within the study area. The results indicate the existence of a hierarchy. Furthermore, empirical observation finds distinct complementarity relationships, rank-size distributions, and co-operative actions between the different cities, thus substantiating the claim that central place theory can be incorporated into an overall regional urban system. Besides, the presence of the densely distributed modern infrastructure system also appears to constitute a dimension of the overall urban system. There need further theoretical and empirical studies in order to support this proposition.

Materializing the “Urban Region” Concept by Integrating Ecological Networks and Central Place Theory

This paper attempts to integrate urban development and ecological conservation by applying and syncretizing the “urban region” concept from landscape ecology and the “city-region” concept from socioeconomics. First, various concepts pertaining to regions are discussed and then, the integration of ecological conservation and urban development on a regional scale is introduced. Subsequently, the Greater Pearl River Delta, in China, is used as a case study area and landscape ecology’s “urban region” concept is applied to produce a landscape spatial arrangement framework for an urban region. This framework is achieved through the following steps: conceiving the study area as a region that consists of two urban regions, arranging ecological conservation landscapes by establishing a regional ecological network within the urban-region rings;and formulating an urban development strategy using central place theory. The resulting landscape spatial arrangement solution includes natural protection areas that cover half of the study area, several key strategic urbanizing locations, and suggestions for the strict protection of certain agricultural land-use areas. We believe that this framework facilitates a feasible exploration of land-use planning on a regional scale, although more in-depth studies are required to refine this approach.

Evolutionary model of the central place hierarchical system

Central place theory is one of the two theoretical cornerstones of geography, yet it cannot be connected with other spatial structure models, fails to provide definite time-space parameter conditions, lacks an evolutionary process model, and does not easily enable construction of a complete theoretical system of regional spatial structure. This paper gives an in-depth analysis of the process and mechanism for production and evolution of central places of different grades, and constructs an evolutionary model of the central place hierarchical system. The results of deduction, analysis and simulation show that production and evolution of the central place hierarchical system may be divided into five stages. These stages are the embryonic, formative, improvement, maturation, and advancement stages. Affected by spatial location and centricity, central places have obvious differences in scale and functional structures. There are great differences in the scale of same-grade central places. However, low-grade central places could have larger scales than high-grade central places, and the central places of a central location may form the agglomeration area of central places. Based on the hypothesis condition of an isotropic plain, the research shows that it is possible not only to form proportional functional structures of central places, but also to produce non-proportional scale structures of central places, and thus to complete the transformation from rationalistic deduction of spatial equilibrium mode to an explanation and demonstration of an unbalanced practical model.

Central Place Theory and Distribution of Post Offices in Cities

The feasibility of application of the Central Place Theory in the distribution of post offices in cities is analysed, the grade scale structure and space distribution structure Shijiazhauang of post offices in city are studied, the research results prove the actual value of the Central Place Theory, and the suggestion of adjustment in the space distribution Shijiazhuang of post offices in city is put forward.

Diverse foraging strategies of breeding Swinhoe's Storm-petrel in the productive marginal sea of the Northwest Pacific

Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel.

由创作地与赋作中心地的离合论汉赋的颂讽怨娱功能

赋体颂讽功能多使用在赋家居于或趋近政治中心之际,而怨娱功能则多使用在偏离政治中心或打算偏离之际,两者皆可以由赋篇创作地及赋作中心地窥探一二。如果仔细梳理赋体流变的历史,也会发现汉代大赋、言志赋、行旅赋、抒情小赋的流变与汉赋创作地、赋作中心地以及赋体颂、讽、怨、娱功能有一定的关联。

都市圈新城区乡村医疗服务中心地网络结构及其影响因素研究——以武汉市新城区为例

医疗服务是维护居民健康的重要保障。基于修正引力模型和社会网络分析法,分析武汉市6个新城区乡村医疗服务中心地空间网络结构及其影响因素。研究表明:(1)新城区乡村医疗服务中心地呈现网络结构,多中心层级化共存。医疗服务网络密度整体上处于初级阶段,总体关联度偏低,且大部分联系限于各区内部,整体节点聚集度较低。医疗服务中心地的网络非均衡性明显,形成了不同尺度的空间嵌套格局。(2)医疗服务中心地可分为6个子群,并呈现由内到外的圈层结构。6个子群的空间关联网络由北向南形成层次分明的板块,而且呈现出小团体现象。特别需要指出的是,子群的划分表现出鲜明的邻近指向特征,地理邻近关系对医疗服务中心地关联强度的影响比较明显。(3)空间邻近性、农业产值、第二产业企业注册资本、人口数量、城镇化水平、道路密度和交通可达性对新城区乡村医疗服务中心地空间关联网络强度的提高具有显著影响,而第三产业企业的影响并不显著。

西部地区相对集中行政许可权改革的路径选择--基于西部X市的实地调研

行政审批制度改革是加快政府职能转变、深化行政体制改革的重要抓手。相对集中行政许可改革作为现阶段行政审批制度改革的主要方式,在实践中存在两种改革模式:“三集中三到位”和“一枚印章管审批”。通过对西部地区X市开展实地调研,从公众满意度和政府职能转变双重视角出发对比两种模式,进而探讨“一枚印章管审批”同西部地区经济社会发展状况的适配性。分析可得“一枚印章管审批”改革模式更适宜在西部地区推广,但需要谋划建立科学机制以实现高效审批和审管联动。

湘中稻草湾锑矿区矿体空间分布规律及深边部找矿预测

稻草湾锑矿区位于湘中锡矿山锑矿田的北部,是近年来新发现的隐伏锑矿床,通过钻孔和坑探工程控制,锑矿资源规模已达到中型,是近年老矿山边部找矿的重要突破。通过对该矿床矿体空间分布特征以及控矿条件进行分析预测找矿靶区。经研究表明,锡矿山矿田各矿床的矿体自特定的层位产出,具有方向性、成群性、等距性等特征;矿体呈层状、似层状产出于上泥盆统佘田桥组(D_(3)s^(2))硅化灰岩和层间破碎带中;矿体受构造控制明显,稻草湾背斜为矿体富集提供虚脱空间;矿体的成矿有利岩性组合为佘田桥组(D_(3)s^(2))灰岩+佘田桥组(D_(3)s^(3))钙质页岩(总屏蔽层)。

隧道中心水沟及现浇盖板施工技术研究

隧道中心水沟传统施工工艺一般采取分次浇筑,沟壁模板易上浮,沟壁烂根,沟底、沟壁结合部位渗水,盖板在预制场预制后运输至现场安装,占地面积大,阻碍交通,施工效率低,施工代价大。基于以上原因,依托彭水特长隧道中心水沟施工,积极探索新技术,提出沟底、沟壁利用底部设置斜坡接口的组合钢模一次施工,采用滑动底模在现场进行盖板现浇施工,每次施工长度15m,工序循环快,施工效率高,节省了大量的人力、物力,该技术可推广应用至诸多盖板沟槽施工。

河南乡村姓氏地名的构成及文化价值

姓氏地名是传统地名的一个主要种类。河南的乡村姓氏地名,依托4000多年的文明史,留下了历史文化的特有印痕。从地名通名的构成来看,来源比较广泛。地名专名,有的使用单纯一个姓氏,有的使用复合姓氏。姓氏与地名有着密不可分的关系,古代中国以家族为单元的传统村落形态特征使然。我们应保护姓氏地名实体,传承古地名“非遗”;研究姓氏地名,挖掘运用根亲文化;弘扬姓氏地名文化,助力新时代乡村振兴。这也是我们的历史使命。

区域金融中心建设与金融资源空间格局优化省域单中心与多中心的比较

在新发展阶段,积极建设区域金融中心成为地方政府促进经济高质量发展的重要抓手,并导致中心城市发展对金融资源配置空间格局的影响日益增强。运用拓展的新经济地理学“中心地”模型分析表明,区域金融中心建设会形成中心城市对外围城市金融资源的虹吸效应,而城市间距离的增加和多中心布局可以弱化这种虹吸效应。选取12个单中心省域和6个双(多)中心省域,以2006—2019年为样本期间的分析发现:在单中心省域,中心城市金融集聚水平的提高对外围城市中小银行分支机构增长具有显著的负向影响,这种负向影响随外围城市与中心城市的距离增大而减弱;在双(多)中心省域,中心城市之间的交互作用(相互竞争)弱化了单个中心城市金融集聚对外围城市中小银行分支机构增长的负向影响;上述影响在地级市层面和县级市层面、对于不同类型的中小银行均存在,具有广泛性和普遍性。目前,多数省域的金融中心建设采取单中心模式,少数采取多中心模式。有条件的省域应适时采取多中心模式或构建多层次的金融中心体系,同时也要重视和激励外围城市的金融发展及其从业人员效用水平的提高。

基于客流特征的轨道站点影响区和轨道站点之间功能布局研究——以厦门为例

轨道站点影响区和站点之间功能布局是落实TOD理念(Transit-Oriented-Development)——以公共交通为空间开发导向的重要内容,客流是站点功能布局成效的直接体现。通过轨道站点影响区POI结构,将厦门轨道站点分为单主导功能、双主导功能和混合功能3类。通过分析站点客流量,明晰站点影响区功能布局与出行发生之间的关系。以站点间客流OD量及站点客流OD在各距离段的分布,分析站点之间功能布局与空间客流分布的关系。根据现状呈现出来的轨道站点功能布局特征及对应的客流特征,提出下一步发展策略。结果表明:1)高客流量站点以单、双主导功能站点为主,混合功能站点客流量并不突出;2)同类型站点间OD量较小,不同类型站点间OD量较大,空间站点功能互补性直接影响OD的空间特征;3)站点各距离段OD比例受中心地职能等级及周边站点功能互补性的双重影响。文章基于对站点影响区和站点之间功能布局与乘客出行相关关系的分析,结合城市功能布局的市场规律及城市空间结构发展需求,提出站点影响区“混合基本功能,集聚主导功能”和站点之间“差异互补,连点成轴”的功能布局原则,以期为以轨道交通为主体的TOD综合开发提供参考。

建制镇功能演变下县-镇-村空间模式——以广东省两县为例

基于地方志等文献,对建制镇的功能演变进行讨论,并采用2021年住房和城乡建设部开展的乡村建设评价中村民问卷调查数据,辅以实地调研,对当前广东省翁源、阳西两县的建制镇在县-镇-村体系中所承担的功能与角色进行分析,并在此基础上探讨县-镇-村空间模式与建制镇作用的演变。研究发现,当前建制镇日益成为综合服务功能空间,在市场交易、学前教育、义务教育与基础医疗等方面发挥着重要作用,是“等级+网络”的县-镇-村空间结构中连接城乡的重要节点。不同类型功能的服务体系在县-镇-村空间模式中呈现中心地结构与县城中心结构的差异。因此,未来在建制镇建设中,除完善基础设施建设外,还应考虑不同类型建制镇与功能的人口规模与服务门槛,实现资源的合理配置。

黑龙江省贫困村空间分布特征与交通可达性差异研究

以黑龙江省20个国家级贫困县和8个省级贫困县的1 359个贫困村为研究对象,基于Arc GIS 10.2空间分析平台,通过最近邻指数分析黑龙江省贫困村的空间分布特征,通过缓冲区分析和成本距离分析黑龙江省国家级贫困县贫困村和省级贫困县贫困村的距离可达性和时间可达性差异。结果表明,(1)黑龙江省贫困村空间分布整体上呈集中分布态势,省级贫困县贫困村的集聚程度高于国家级贫困县贫困村。(2)黑龙江省贫困村至一级、二级、三级中心地距离可达性水平均依次升高。(3)黑龙江省国家级贫困县贫困村至一级、二级、三级中心地时间可达性水平依次升高,省级贫困县贫困村至一级、二级、三级中心地时间可达性水平依次降低。

2020-2021年苏州市公共场所集中空调通风系统卫生状况

目的了解苏州市公共场所集中空调通风系统卫生状况。方法采用随机抽样的方式于2020年7—8月至2021年8—9月对苏州市区正常使用的38家次集中空调通风系统进行卫生监测,检测送风中PM_(10)、细菌总数、真菌总数、β-溶血性链球菌,风管内表面细菌总数、真菌总数、积尘量,冷却水中嗜肺军团菌,依据《公共场所集中空调通风系统卫生规范》(WS 394-2012)和《公共场所卫生检验方法》(GB/T 18204.5-2013)进行采样和检测。结果2020—2021年检测的38家次集中空调通风系统中,检测指标总体合格率为93.8%,各场所中宾馆酒店合格率最高,医疗场所合格率较低,差异有统计学意义(χ^(2)=11.87,P<0.05)。集中空调送风指标PM_(10)、细菌总数、真菌总数、β-溶血性链球菌合格率分别为97.8%、92.4%、76.1%、100.0%,各指标间差异有统计学意义(χ^(2)=41.81,P<0.05);风管内表面细菌总数、真菌总数、积尘量合格率为98.4%、89.5%、100.0%,各指标间差异有统计学意义(χ^(2)=20.42,P<0.05);冷却水中嗜肺军团菌检出率为10.5%。结论苏州市公共场所集中空调通风系统卫生状况总体较好,但真菌和军团菌污染需要加以关注。

基于图像识别的隧洞排尘控制系统分析

随着信息化、智能化、网络化的发展,计算机图像识别技术已在多数领域得到广泛应用。云南TB水电站在进行过坝隧洞通风及照明系统升级时,设计了一套基于图像识别的排尘控制系统,分析了系统的组成、网络、集中控制级、现地控制站和图像识别控制,探讨了图像识别的关键技术。