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突发公共卫生事件影响范围广且对公众健康危害严重。疾病预防控制中心（CDC）作为中国疾病预防控制与公共卫生技术管理和服务的重要机构,其对突发公共卫生事件的应急反应能力会直接影响应急处置效果,而及时反应可以在第一时间为民众提供有效信息,在最大程度上减少突发事件造成的恐慌,因此,科学地评价CDC部门对突发公共卫生事件的应急反应能力十分重要。本研究以2016年3月18日在山东省发生的非法疫苗事件为例,收集了事件发生后各地级市CDC部门官网上公布的相关信息,并采用时空分析的方法,对中国地市级CDC部门突发公共卫生事件应急反应能力进行了评价。研究方法包括对疫苗事件各地市CDC部门的反应速度和内容的时空可视化分析,以及基于空间扫描统计量方法的CDC部门疫苗事件应急反应的空间聚集性分析,结果显示中国各地CDC部门信息化建设存在地域不均现象;西南地区CDC部门官网对突发公共卫生事件反应明显比其他区域迅速,且具有显著的空间聚集性;山东省和河南省作为疫苗事件中问题疫苗的流通大省,是此次事件的高风险区域,但是其CDC部门的反应速度较慢,对突发公共卫生事件的应急反应能力较弱。 相似文献
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互联网页面和社交网络文本中蕴含丰富的道路交通信息,是其他交通信息采集平台的有效补充。然而,自然语言文本形式的交通信息多以线性参考或地标方位描述交通事件空间位置,且大量存在事件元素缺失或隐含现象,对交通信息的自动化抽取有着较大影响。考虑到交通信息的自然语言表达方式虽然自由随意,但表达模式相对固定,提出一种从互联网文本中抽取道路交通信息的模式匹配方法。首先,基于道路交通事件描述的语言特征构建模式库;然后,以特征词词性序列的形式表达互联网文本和抽取模式,利用DTW距离度量序列相似度,实现抽取模式匹配;最后,在匹配抽取模式和填补规则指导下获取结构化的道路交通信息。由上海市城市交通相关门户网站和微博客平台的实验过程显示,本文所提出的模式匹配方法,抽取道路交通信息的准确率和召回率分别达到90%和80%以上,表明该方法能有效抽取互联网文本蕴含的道路交通信息,且实现过程相对简单,易于扩展,具有可用性。 相似文献
3.
Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economic structure adjustment and city economic growth, producer services have begun to play an increasingly important role in city-region networking. This paper employs the methodology of world city network to analyze and explain the spatial development characteristics of China’s urban network system based on the data of nationwide producer services enterprise network. The research result indicated that the distribution of producer services network has a positive effect on the development of Chinese city networks. City network connectivity is closely related to the significance of city in producer services development, and the former will gradually decline with the drop of the latter. Accordingly, the 64 cities can be divided into the national central cities, regional central cities, sub-regional central cities and local central cities in accordance with their position and role in the nationwide producer services network. It is concluded that high-grade cities with quality producer services dominate the pattern of Chinese city networks and there emerges three spatial agglomerations of producer services enterprises in Changjiang (Yangtze) River Delta, Zhujiang (Pearl) River Delta and Beijing-Tianjin-Tangshan Economical Region. Moreover, the distribution of different producer services industry varies from city to city, which also affects the characteristics of network development. 相似文献
4.
Ben Derudder Zhan Cao Xingjian Liu Wei Shen Liang Dai Weiyang Zhang Freke Caset Frank Witlox Peter J. Taylor 《中国地理科学(英文版)》2018,28(2):183-201
Against the backdrop of the sizable economic growth of China in recent years, this paper uses the most recent data gathering of the Globalization and World Cities(Ga WC) research network to update and supplement earlier research on the shifting global connectivity of Chinese cities. The update consists of an evaluation of the connectivity of Chinese cities in 2016, the supplement of an analysis of the changing position of Chinese cities in the world city network between 2010 and 2016. To this end, we build on a specification of the world city network as an ‘interlocking network' in which producer services firms play the crucial role in city network formation. Information about the presence of leading producer services firms in cities in 2010 and 2016 is used as the input to a bipartite network projection algorithm in order to measure cities' network connectivity. The first set of results discusses the geographies of urban connectivity in the world city network in 2016. The second set of results discusses standardized measures of change to reveal the major dimensions of the transformations between 2010 and 2016. We find that, with the exception of Hong Kong, Macau and Kaohsiung of Taiwan, all Chinese cities record connectivity gains. This wholesale rise in connectivity is nonetheless geographically uneven, with above all Beijing, Chengdu/Chongqing and Changsha/Wuhan becoming more connected. We conclude that the wholesale rise of Chinese cities in the world city network and their changing trajectories in the post-crisis era are embedded in shifting external and internal political economies. 相似文献
5.
中国历史文化研究一直是中国文学研究的热点,大量的研究都是基于文学作品本身或文人个体特征进行,缺乏大数据的支持;历史的发展是大量个体共同驱动的结果,文化地理中众多文人的行为潜在影响着古代文化分布和变迁。本文提出基于文人群体运动行为的位置关联和聚合的大数据分析方法,根据唐宋时期文人的移动足迹数据来论证中国历史上的文化中心城市的变迁。文化地理领域中的3次文化中心转移的观点,是基于3次历史事件驱动的定性推理分析,缺乏有效的古代文化方面的数据支撑。本文力图从数据科学、信息科学和GIS分析角度来审视这一结论。从人文领域已经出版的学术研究著作中采集唐宋时期具有代表性作家的11万条足迹数据,利用GIS的位置关联技术形成足迹图,构建了文人迁徙网络图;并采用空间化的PageRank算法计算出唐宋时期各城市的文化吸引力,直观地呈现出了不同时期文人聚集的中心城市,重塑唐宋文化中心变迁。同时,从定量、地理位置变化和时序角度剖析了中国不同时期城市的文化吸引力的分布和变化。为论证中国文化中心的南北变迁,对唐宋时期的城市文化吸引力聚合,以20年间隔来科学计算出南北文化中心的对比和演变,科学表现文化中心的南北随时间的变化,论证了中国文化中心3次南移的后2次,发现中国文化中心南移的时间早在北宋时期就已完成。 相似文献
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Measurement and interpretation of connectivity of Chinese cities in world city network, 2010 总被引：5，自引：3，他引：2
Ben DERUDDER Peter J TAYLOR Michael HOYLER NI Pengfei LIU Xingjian ZHAO Miaoxi SHEN Wei Frank WITLOX 《中国地理科学(英文版)》2013,23(3):261-273
This is an empirical paper that measures and interprets the position of Chinese cities in the world city network in 2010. Building on a specification of the world city network as a′interlocking network′in which business services firms play the crucial role in city network formation, information is gathered about the presence of global service firms in cities. This information is converted into data to provide the′service value′of a city for a firm′s provision of corporate services in a 526(cities)×175(firms) matrix. These data are then used as the input to the interlocking network model in order to measure cities′connectivity and its predominant geographical orientation. Here we focus on the position of some key Chinese cities in this regard, and discuss and interpret results in the context of the urban dimensions of the′opening up′of the Chinese economy. 相似文献
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随着移动互联网、云计算、大数据等新一轮信息通信技术的发展,智慧城市逐渐成为城市建设的重要发展趋势。“十三五”期间,全国各城市纷纷制定智慧城市建设或发展规划,并将其定位为城市中长期发展战略的重要组成部分。由于智慧城市涉及范围广泛、内容体系庞杂,目前还在不断发展完善之中,尚未形成统一的评价标准。基于此,本文对比了国内外智慧城市评价重点与趋势,以提高城市可持续发展能力、实现高效、公平的城市管理、保障民生福祉为目标,构建了包括智慧经济、智慧交通、智慧医疗、智慧教育、智慧管理等多子系统的智慧城市评价指标体系;运用文本、网页、统计等多源数据,本文开展了全面的、统一的、多层次、模块化的全国智慧城市发展状态评估,并从子系统协调程度对智慧城市发展提出了建设性意见。研究发现：① 从整体评价结果分析,除北京、上海、广州、武汉、成都、杭州、天津和南京8个城市综合得分及各子系统得分都较高外,绝大部分城市的智慧建设水平不高;② 在空间分布上,沿海地区的智慧城市建设水平普遍高于内陆地区,直辖市和省会城市高于其他城市;③ 从协调关系分析,70%以上城市的5个子系统为中度甚至低度协调,80%以上城市以智慧教育或智慧医疗成为发展短板,这也是未来政府应关注的重点。本文通过构建指标体系,探讨了中国智慧城市的发展状态,为城市未来的发展和管理提供了借鉴与参考。 相似文献
8.
Duringtheprocessofnationaleconomy'stransi-tion,thedeterminantpowerofeconomicdevelopmenthaschangedgraduallyfromcentralgovemmenttolocalgovemments.Cities,asthecenterofregionaleconomicdevelopment,notonlydeterminethecompetitivenessoftheregionbuthavebecomethemainimpetusforthechangesofmacroeconomicpatternasweIl.Sotaking2o9perfecture-levelcitiesasresearchsubjects,weanalyzethemacropatternofurbancompetitivenessandcomprehendtheinternalimpetusandmechanismofre-gionaldevelopment,whichhavegreatsignificanceon… 相似文献
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作者选择电子政务中政府门户网站最具代表力的国家各部、委、局网站为调查对象,采用多种方式、详细调查、分析了网站中地图的应用状况,根据调查结果将各部、委、局网站分为“空间信息非密切相关政府网站”和“空间信息密切相关政府网站”两类。通过对地图应用的分类、地图数据形式的总结,发现了目前政府门户网站中地图应用存在的一些问题,例如,地图数量少、功能挖掘不充分、缺少非中文版本地图等。最后对门户网站的地图应用方向作了合理而大胆的预测。 相似文献
11.
At present, paid urban landuse system is one of the most important economic reform in China. In the other words, landuse right
can be transferred and land users must pay the rent to the state according to the quality of land. It is necessary to apply
the theory of rent and location to the economic approaisal of urban land.
China is vast in territory. Is’s geographical condition and economic development vary from place to place, so does the urban
land value. In order to reveal the difference of land value between different cities, the following method is used. (1) Analysing
the factors and elements that affect the quality of urban land. Six factors including 17 elements were selected in this paper:
macrolocation of a city, benefit of urban aggregation, infrastructure investment, output value of urban land, potential of
urban land, and investment intensity. (2) Deciding the weight andvalue of each factor. (3) Appraising each element separately.
(4) Accounting the value of all factors and getting the total appraisal score of each city. (5) Grouping the 430 Chinese cities
into sevencategories according to the appraisal values.
The result shows that all the cities in the category with the highest land output values are in the coast belt, whereas most
cities in the inland and outlying areas are belong to the category with low rank. For example, 87% of the cities in the outlying
regions are belong to the lowest rank. Although there are some relationship between the size of cities and urban land rank,
generally speaking, the larger the city, the higher the urban land rank. In fact, the locational condition is the most important
factor which influences the rank of urban land. 相似文献
12.
Spatio-temporal Analysis of Urban Spatial Interaction in Globalizing China —— A Case Study of Beijing-Shanghai Corridor 总被引：1，自引：1，他引：0
This paper aims to explore urban geography with a new perspective. Endowed with the urban geography connotations, an improved data field model is employed to integrate temporal dimension into spatial process of cities in a typical region in this article. Taking the Beijing-Shanghai Corridor including 18 cities as an example, the authors chose the city centricity index (CCI) and the spatial data field model to analyze the evolution process and features of sub-region and urban spatial interaction in this corridor based on the data of 1991, 1996 and 2002. Through the analysis, we found that: 1) with the improvement of the urbanization level and the development of urban economy, the cities' CCI grew, the urban spatial radiative potential enhanced and the radiative range expanded gradually, which reflects the urban spatial interaction's intensity has been increasing greatly; 2) although the spatial interaction intensity among the cities and sub-regions in the Beijing-Shanghai Corridor was growing constantly, the gap of the spatial interaction strength among different cities and sub-regions was widening, and the spatial division between the developed areas and the less developed areas was obvious; and 3) the intensity of the spatial interaction of Beijing, Shanghai and their urban agglomerations was far greater than that in small cities of other parts of the corridor, and it may have a strong drive force on the choice of spatial location of the economic activities. 相似文献
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董黎明，李向明，冯长春ＡＳＴＵＤＹＯＮＲＥＧＩＯＮＡＬＤＩＦＦＥＲＥＮＣＥＯＦＣＨＩＮＡ＇ＳＰＡＩＤＵＲＢＡＮＬＡＮＤＵＳＥＳＹＳＴＥＭＡＮＤＧＲＡＤＩＮＧ￥ＤｏｎｇＬｉｍｉｎｇ；ＬｉＸｉａｎｇｍｉｎｇ；ＦｅｎｇＣｈａｎｇｃｈｕｎ（ＰｅｋｉｎｇＵｎｉ... 相似文献
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In recent years,researchers have devoted considerable attention to identifying the causes of urban environmental pollution.To determine whether migrant populations significantly affect urban environments,we examined the relationship between urban environmental pollutant emissions and migrant populations at the prefectural level using data obtained for 90 Chinese cities evidencing net in-migration.By dividing the permanent populations of these cities into natives and migrants in relation to the population structure,we constructed an improved Stochastic Impacts by Regression on Population,Affluence and Technology model(STIRPAT)that included not only environmental pollutant emission variables but also variables on the cities’attributes.We subsequently conducted detailed analyses of the results of the models to assess the impacts of natives and migrants on environmental pollutant emissions.The main findings of our study were as follows:1)Migrant populations have significant impacts on environmental emissions both in terms of their size and concentration.Specifically,migrant populations have negative impacts on Air Quality Index(AQI)as well as PM2.5 emissions and positive impacts on emissions of NO2 and CO2.2)The impacts of migrant populations on urban environmental pollutant emissions were 8 to 30 times weaker than that of local populations.3)Urban environmental pollutant emissions in different cities differ significantly according to variations in the industrial structures,public transportation facilities,and population densities. 相似文献
15.
城市是人类文明的主要组成部分,是伴随人类文明与进步发展起来的。在城市建设飞速发展的今天,对古近代城市发展演变的研究显得尤为重要,其中一个重要的手段就是借助于城市地图。城市地图可相对准确地反映出当时城市的空间形态,对于研究城市历史平面布局变迁具有重要的参考价值。本文以近代城市地图（明、清、民国时期的城市地图）为主要研究对象,从其对传统城市地图的继承与受西方文化及先进测绘制图技术影响发展的角度,探究近代城市地图的类型特点、发展方向与价值。近代城市地图一方面既没有完全摆脱传统城市舆图在绘图手法和表现内容上的特点,另一方面又受到西方制图技术和文化的冲击与推动,在继承与发展中逐渐趋向多样化、专题化和近代化,并且能充分反映该时期城市发展的特点与地域特色。本文分别从同一城市（以北京为例）不同时期的城市地图和不同城市典型的城市图2个角度进行分析,讨论并总结了近代城市地图在表现手法、内容和绘图技术等方面的特征及地图本身的价值。 相似文献
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In China, the land resource per person is poor withregard to the huge number of population. According tothe recent data from the National Land Bureau, theaverage land per person is 0. 11 ha, much less than0. 25 ha, the average land per person in the world(FAN, 1997). On the other hand, a large scale ofrural land is to be transmitted into urban land upon thefast proceeding of urbanization. At present, the urbanpopulation occupies about 30% of the total in China. Ifthe percent become 50% (th… 相似文献
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突发性重大公共传染性疫情在地级城市层面政府严格防控时期的时空演变特征能够有效反应我国综合应急防控能力。基于中国2020年1月24日—3月5日312个城市的COVID-19累计确诊数、现有确诊数、治愈数等统计数据,采用ESDA、优化的热点分析、空间马尔科夫链、空间面板数据模型等方法分析了政府严控期COVID-19疫情在312个城市的时空变化特征。研究发现：① 全国COVID-19现存确诊数经历了“快速增长扩散、基本控制、逐渐下降、局部地区完全控制”的变化特征并在2月17日达到峰值,上升期的日均增长率为17.5%,下降期的日均下降率为5.1%,绝大部分城市的疫情变化特征与全国总体情况类似;② 春运期间的人口流动性高是导致疫情快速扩张的主要原因,武汉“封城”之前14 d的百度迁徙强度指数与部分城市的累计确诊数显著相关;③ 优化的热点分析方法识别出疫情热点的空间分布具有固定性且主要分布于以武汉为中心、半径约350 km范围内的36个城市,未识别出具有统计显著性的疫情冷点城市;④ 对各城市现有确诊人数的马尔科夫链转移概率矩阵分析结果显示,各种类型维持现状的概率大于0.85,向下转移的平均概率明显高于向上转移的概率,在不同空间滞后类型的影响下各类型转移概率发生明显变化;⑤ 空间面板数据模型估计结果显示312个城市的现存确诊数具有显著的空间和时间自相关性。本研究从地级市层面多角度分析了政府严控期间COVID-19疫情的时空变化特征,疫情防控重点在于降低其时空自相关效应,为我国当前及未来应对突发性重大公共传染性疫情提供决策参考。 相似文献
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Shujuan Li 《中国地理科学(英文版)》2016,26(5):577-588
A large number of studies have been conducted to find a better fit for city rank-size distributions in different countries. Many theoretical curves have been proposed, but no consensus has been reached. This study argues for the importance of examining city rank-size distribution across different city size scales. In addition to focusing on macro patterns, this study examines the micro patterns of city rank-size distributions in China. A moving window method is developed to detect rank-size distributions of cities in different sizes incrementally. The results show that micro patterns of the actual city rank-size distributions in China are much more complex than those suggested by the three theoretical distributions examined(Pareto, quadratic, and q-exponential distributions). City size distributions present persistent discontinuities. Large cities are more evenly distributed than small cities and than that predicted by Zipf′s law. In addition, the trend is becoming more pronounced over time. Medium-sized cities became evenly distributed first and then unevenly distributed thereafter. The rank-size distributions of small cities are relatively consistent. While the three theoretical distributions examined in this study all have the ability to detect the overall dynamics of city rank-size distributions, the actual macro distribution may be composed of a combination of the three theoretical distributions. 相似文献
20.
Urban redevelopment,gentrification and gentrifiers in post-reform inland China: A case study of Chengdu,China 总被引：1，自引：0，他引：1
Since its process evolved in recent years, the definition of gentrification has expanded to cover different forms of social upgrading, new spaces and new actors around the world. Studies on gentrification in Chinese cities began to take off in the 2000 s. However, they all mainly focused on the newly emerging global cities and there has been a lack of investigation on provincial cities. Furthermore, discussions on gentrifiers′ profiles and their motivations for housing choice are absent from literature on Chinese gentrification. Therefore, this paper aims to assess the relevance of the broad definition of gentrification in provincial Chinese cities through empirical research on urban redevelopment projects in Chengdu, and to examine the characteristics of gentrifiers(as new incoming residents) in it. The results show the rationality of gentrification processes as urban redevelopment in Chengdu, and reveal original outcomes on the corresponding gentrifiers′ profiles and the motivations behind their housing choice, which are different from the general features of gentrifiers in standard Western gentrification research. 相似文献