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1.
城市实体特征对城市网络空间影响力的作用机制——基于互联网新闻媒体的分析 总被引：5，自引：1，他引：4
借助百度新闻媒体指数功能,收集281个地级市或以上城市在2011~2014年间的媒体指数,分析基于互联网新闻媒体的城市网络空间影响力差异及其变化。其次,通过对面板数据的回归分析,从政府因素与市场因素两个方面探讨城市在实体空间中的特征（或传统影响力）是如何作用到城市在网络空间中的影响力。并且,通过对各年数据的回归分析,进一步考察政府因素与市场因素作用机制的演化过程。 相似文献
2.
演化经济地理强调与本地的技术关联对技术演化的影响,在建设科技创新中心的过程中,向复杂技术的升级需要充分考虑本地技术结构及演化特点。论文以北京、上海和深圳3个国际科技创新中心建设城市为例,将复杂性和关联性纳入研究框架,比较分析技术关联和复杂性对城市技术演化的影响。研究发现,北京、上海和深圳的技术结构、技术关联度、复杂性和演化路径存在明显的差异。上海的技术关联度较高,而复杂度偏低;深圳的技术关联度最低,技术复杂度最高;北京居中。从演化趋势看,北京经历了明显的向复杂技术演化的过程;深圳的整体技术复杂度上升幅度最大,但在2006年以后出现向低复杂度技术多元化发展的趋势;上海的技术复杂度上升幅度最小。计量分析表明,与本地技术关联越强的技术越有利于成为3个城市下一阶段的优势技术,但复杂度高的技术更容易成为北京下一阶段的优势技术,对上海和深圳的技术演化没有显著影响。未来国际科技创新中心建设需要充分考虑本地技术基础和演化特征,并制定针对性的技术发展策略。 相似文献
3.
技术关联性、复杂性与区域多样化——来自中国地级市的证据 总被引：1，自引：0，他引：1
忽视现实基础,盲目追求新兴产业的现象普遍存在于当前中国的一些城市。基于国家知识产权局的专利数据,描绘1987—2016年中国地级市技术关联性和复杂性的时空演化特征,探讨两者对区域技术进入和增长的影响。结果表明：① 新技术的本地关联度越高,就越有可能进入该地区;现有技术的本地关联度越低,就越容易退出该地区;② 中国城市的技术发展总体上呈现路径依赖特点。其中,东部地区的技术关联性和复杂性变化较大,中西部地区变化较小;③ 技术关联性对新技术的进入和增长起到显著的促进作用。在引入复杂性较高的技术时,只有存在较高关联性才会促进区域的技术进步。最后提出的区域多样化发展框架,可为决策者权衡选择技术发展道路提供参考。 相似文献
4.
Yaqiong Liu Hock Soon Seah 《International journal of geographical information science》2013,27(6):953-979
Recently, points of interest (POIs) recommendation has evolved into a hot research topic with real-world applications. In this paper, we propose a novel semantics-enhanced density-based clustering algorithm SEM-DTBJ-Cluster, to extract semantic POIs from GPS trajectories. We then take into account three different factors (popularity, temporal and geographical features) that can influence the recommendation score of a POI. We characterize the impacts caused by popularity, temporal and geographical information, by using different scoring functions based on three developed recommendation models. Finally, we combine the three scoring functions together and obtain a unified framework PTG-Recommend for recommending candidate POIs for a mobile user. To the best of our knowledge, this work is the first that considers popularity, temporal and geographical information together. Experimental results on two real-world data sets strongly demonstrate that our framework is robust and effective, and outperforms the baseline recommendation methods in terms of precision and recall. 相似文献
5.
基于关联度和复杂度的中国城市技术引入模式及其演化机制 总被引：2，自引：1，他引：1
"创新驱动发展"是中国的重要发展战略,论文利用中国知识产权局记录的城际技术转移专利条目数据,从关联度和复杂度入手,借助Gephi、ArcGIS、Stata等工具,探索中国城市的专利技术引入模式.论文以城市引入技术的平均关联度、平均复杂度为标尺,划分出"高关联度—高复杂度""低关联度—高复杂度""低关联度—低复杂度""高... 相似文献
6.
基于SD法的城市感知研究——以浙江台州地区为例 总被引：2，自引：0，他引：2
借助SD法即语义差别法获取人们对台州地区9个城市的整体感知,并研究这些感知与代表城市特征的客观指标之间的关系,为营造宜人的城市环境提供参考。结果表明,台州城市群总体特点较为中庸,但各城市特点各异,基本能分为三组;城市的感知和城市的客观指标之间存在着一定关系;与客观指标预期相关的感知和实际相关的感知存在一定出入;各种指标对感知的影响力由大到小依次为经济指标、规模指标、区位指标和建设指标;经济总量对感知的作用大于人均经济量的作用;受到客观指标影响程度由大到小的感知依次是:城市现代化的感知、城市规模和繁华度的感知、城市有序度和城市心理距离的感知、城市尺度的感知;通过进一步的回归分析,最后得到了特定感知量级下对应的城市客观指标值。 相似文献
7.
地理距离对中国民营企业银行贷款的影响 总被引：1，自引：0，他引：1
地理距离是企业银行贷款过程中的客观约束,而地理距离对资本流动的影响是金融地理学的基本命题。在分析地理距离对企业银行贷款作用机理的基础上,采用中国银行业分支机构与民营上市公司贷款数据,刻画城市银企贷款的地理距离特征,探究地理距离对企业银行贷款的影响。研究发现：① 银企地理距离对企业贷款规模具有显著负向影响,地理距离越近,贷款额度越多;借贷双方地处相同城市或相同省份时地理距离对贷款规模的影响更为显著。② 中心城市、大型城市和发达城市企业银行贷款相对距离大,而非中心城市、小型城市和欠发达城市企业银行贷款相对距离小。银企地理距离对企业信贷的影响在中心城市、大型城市和发达城市更为凸显。③ 企业规模、上市年龄和国有控股历史可以缓解地理距离对银行贷款额度的约束。④ 信息化水平与地理距离在贷款可得性上具有替代关系,信息化发展有助于降低地理距离对银行贷款额度的制约,但无法消除地理距离的影响。本文认为缓解地理距离约束对于企业融资具有重要意义。 相似文献
8.
基于城际创业投资联系的中国城市网络结构和组织模式 总被引：3，自引：1，他引：2
鉴于现有的城市网络研究尚没有关注企业间投资这一最重要的经济行为之一,所得认知不全面,本文基于城际创业投资联系这一全新视角,刻画了中国城市网络的结构和组织模式,以丰富城市等级和距离衰减作用下的城市网络研究.从节点看,城际创业投资空间分布不均,高度集中在超大城市和直辖市.从联系看,城际创业投资具有明显的层级性,形成以京沪深... 相似文献
9.
Caglar Koylu 《International journal of geographical information science》2019,33(4):805-832
Interpersonal communication on online social networks has a significant impact on the society by not only diffusing information, but also forming social ties, norms, and behaviors. Knowing how the conversational discourse semantically and geographically vary over time can help uncover the changing dynamics of interpersonal ties and the digital traces of social events. This article introduces a framework for modeling and visualizing the semantic and spatio-temporal evolution of topics in a spatially embedded and time-stamped interpersonal communication network. The framework consists of (1) a topic modeling workflow for modeling topics and extracting the evolution of conversational discourse; (2) a geo-social network modeling and smoothing approach to projecting connection characteristics and semantics of communication onto geographic space and time; (3) a web-based geovisual analytics environment for exploring semantic and spatio-temporal evolution of topics in a spatially embedded and time-stamped interpersonal communication network. To demonstrate, geo-located and reciprocal user mention and reply tweets over the course of the 2016 primary and presidential elections in the United States from 1 August 2015 to 15 November 2016 were analyzed. The large portion of the topics extracted from mention tweets were related to daily life routines, human activities, and interests such as school, work, sports, dating, wearing, birthday celebration, music, food, and live-tweeting. Specific focus on the analysis of political conversations revealed that the content of conversational discourse was split between civil rights and election-related discussions of the political campaigns and candidates. These political topics exhibited major shifts in terms of content and the popularity in reaction to primaries, debates, and events throughout the study period. While civil rights discussions were more dominant and in higher intensity across the nation and throughout the whole time period, election-specific conversations resulted in temporally varying local hotspots that correlated with locations of primaries and events. 相似文献
10.
基于报纸媒体内容分析和信息熵的广交会综合影响力时空分布 总被引：3，自引：0，他引：3
从报纸媒体的角度研究广交会作为重大事件的综合影响力的时空分布特点。以中国知网(http://www.cnki.net/) 所属“中国重要报纸全文数据库”(CCND) 2000-05-05 到2011-05-30 时间段内“广交会”为主题的4333 条新闻报道为研究文本, 通过传播学中的内容分析法建构分析类目, 统计类目包括新闻的时间、所属的届数与期数、报社所在城市、新闻版面、新闻字数等, 共由3 个编码员进行统计, 并对类目编码进行信度检测。在对新闻内容进行计量统计的基础上, 引进信息熵度量信息量, 利用信息熵和报道篇数构建广交会综合影响力指标, 进一步构建广交会空间综合影响力指数方程, 分析广交会综合影响力在全国的分布情况, 并检验综合影响力指标和经济指标的相关性。结果发现:① 从时间分布来看, 以新闻报道数量来衡量, 在事件(广交会) 进行时其综合影响力存在时间衰减现象, 各展期综合影响力的年际变化则呈现为周期性的年度重复现象。② 从空间分布来看, 广交会综合影响力空间分布与城市参展商数量、经济情况和距离有着密切的联系:受影响大的城市主要集中在沿海经济发达的省份, 受影响小的城市主要分布在西部和北部, 整体上综合影响力大小和城市分布的密度由东到西递减;综合影响力总体上存在显著的空间距离衰减, 但对于北京和上海这两个特殊城市而言, 空间距离已经不是广交会综合影响力的主要因素, 而在广交会举办地的“当地”(广东省内) 较短的距离内, 距离衰减并不显著, 当空间距离超出一定范围, 则存在明显的距离衰减现象。 相似文献
11.
地理空间数据本质特征语义相关度计算模型 总被引：1，自引：1，他引：0
关联数据是跨网域整合多源异构地理空间数据的有效方式,语义丰富的关联是准确、快速发现目标数据的关键。根据地理空间数据在空间、时间、内容上的语义关系,提出地理空间数据本质特征语义相关度计算模型。通过构建本质特征的关联指标体系,分层次逐级计算地理空间数据的语义相关度。与传统的语义相关度计算方式不同,以地理元数据为语料库,充分考虑地理空间数据的特点及空间、时间、内容在检索中不同的重要程度,分别采用几何运算、数值运算、词语语义相似度计算和类别层次相关度计算的方式,构建地理空间数据的语义相关度计算模型。该模型具有构建简单、适用于多源异构数据、充分结合了数学运算和专家经验知识等特点。实验表明：模型能够有效地计算地理空间数据本质特征的语义相关度,并具备一定的扩展性。 相似文献
12.
中国工业结对集聚和空间关联性分析 总被引：1，自引：1，他引：0
要推动形成优势互补高质量发展的区域经济布局,就需要从产业关联视角考察中国工业的空间格局.集聚是工业在空间的重要表现形式,通过把测度两两配对产业集聚的结对集聚指数和测度两两配对产业关联度的投入产出表相结合,首次构建集聚关联指数和关联集聚指数,以研究不同空间尺度下空间关联性的差异和出现差异的原因.通过整理中国工业企业数据库... 相似文献
13.
Jinyao Lin 《International journal of geographical information science》2013,27(10):1721-1736
As a consequence of rapid and immoderate urbanization, simulating urban growth in metropolitan areas effectively becomes a crucial and yet difficult task. Cellular automata (CA) model is an attractive tool for understanding complex geographical phenomena. Although intercity urban flows, the key factors in metropolitan development, have already been taken into consideration in CA models, there is still room for improvement because the influences of urban flows may not necessarily follow the distance decay relationship and may change over time. A feasible solution is to define the weights of intercity urban flows. Therefore, this study presents a novel method based on weighted urban flows (CAWeightedFlow) with the support of web search engine. The relatedness measured by the co-occurrences of the cities’ names (toponyms) on massive web pages can be deemed as the weights of intercity urban flows. After applying the weights, the gravitational field model is integrated with Logistic-CA to fulfill the modeling task. This method is employed to the urban growth simulation in the Pearl River Delta, one of the most urbanized metropolitan areas in China, from 2005 to 2008. The results indicate that our method outperforms traditional methods with respect to two measures of calibration goodness-of-fit. For example, CAWeightedFlow can yield the best value of ‘figure of merit’. Moreover, the proposed method can be further used to explore various development possibilities by simply changing the weights. 相似文献
14.
论中国未来城镇化道路的选择 总被引：5，自引：1，他引：4
中国未来的城市化政策应该有利于打破城乡分割体制的限制,并促进资源和要素按照市场的原则合理地向不同规模等级的城镇集中。中国城镇化应当按照"以市场为导向,大中小为一体,促两头带中间"的战略方针,在结构上,以大城市为龙头,以中等城市为纽带,以小城镇为依托;在数量上,适当发展大城市,积极发展中等城市,大力发展小城镇;在借鉴别国的成功经验的基础上,紧密结合中国的实际,探索出一条具有中国特色的城镇化道路。 相似文献
15.
Comparison is now taken as vital to the constitution of knowledge about cities and urbanism. However, debate on comparative urbanism has been far more attentive to the merits of comparisons between cities than it has been to the potential and challenges of comparisons within cities—to what we call “Intra-Urban Comparison” (IUC). We argue that a focus on the diverse forms of urbanism located within cities may generate critical knowledge for both intra- and inter-urban comparative projects. IUCs highlight the diversity inherent in the category “city,” revealing dimensions of the urban that are central to how cities work and are experienced. We mobilise fieldwork within three cities: Mumbai, Delhi and Cape Town, and consider both how these cities have been historically understood as different urban worlds within a city, and discuss key findings from IUCs we have conducted on infrastructures. We find that IUCs can enhance comparative work both within and between cities: reconceptualising urban politics; attending to the varied and contradictory trajectories of urban life; and bringing visibility to the diverse routes through which progressive change can occur. 相似文献
16.
以欧美对中国光伏反倾销、反补贴（“双反”）事件为例,使用网络分析研究2009—2015年世界光伏贸易格局,以Logit模型探讨2009—2011年和2011—2013年中国210个地级市与175个目的国的光伏贸易演变。结果表明,“双反”后中国与欧美贸易量急剧下降,与非“双反”国家贸易量有所提升,主要目的国从德国、荷兰、意大利和美国转向日本、韩国、印度和新加坡。政策激励促进光伏出口,且“双反”后政策效力增强。出口关联显著提升正常贸易环境下出口增长,“双反”后则为负向作用。加工贸易比重高的区域受到贸易保护冲击更为严重。市场多元化不能缓冲“双反”冲击,目的国中心性高有利于建立稳健贸易联系。政策激励在光伏贸易中作用突出,减少直接补贴,增加创新奖励是政策优化方向。 相似文献
17.
Anthony Stefanidis Peggy Agouris Charalambos Georgiadis Michela Bertolotto James D. Carswell 《International journal of geographical information science》2013,27(8):749-772
In this paper we extend our previous work on shape-based queries to support queries on configurations of image objects. Here we consider spatial reasoning, especially directional and metric object relationships. Existing models for spatial reasoning tend to rely on pre-identified cardinal directions and minimal scale variations, assumptions that cannot be considered as given in our image applications, where orientations and scale may vary substantially, and are often unknown. Accordingly, we have developed the method of varying baselines to identify similarities in direction and distance relations. Our method allows us to evaluate directional similarities without a priori knowledge of cardinal directions, and to compare distance relations even when query scene and database content differ in scale by unknown amounts. We use our method to evaluate similarity between a user-defined query scene and object configurations. Here we present this new method, and discuss its role within a broader image retrieval framework. 相似文献
18.
“土地分离”与“土地共享”是2种不同的土地利用思维方式,反映人类土地利用的决策选择。中国有大量包含土地分离和共享思维的实践,但缺乏将这些实践案例纳入统一体系的研究范式。土地分离与共享框架最初用来探索粮食生产与生物多样性保护的权衡关系。经过10多年的发展,其理论内涵和研究内容不断丰富,是地理资源与环境领域重要的研究议题。论文在解析土地分离与共享框架内涵的基础上,综述土地分离与共享框架的相关研究成果,探讨土地分离与土地共享的策略选择。研究发现土地分离与共享相关研究存在从农业环境主题向城市管理主题转化的趋势,而且除了强调单一生物多样性保护和农业生产外,还有少数研究开始关注碳储存、土壤保持等其他生态系统服务类型;尽管土地分离与土地共享策略各有其优势和局限,但在目前的研究和实践中,土地分离比土地共享更受青睐。论文基于土地的多功能性进一步扩展该框架在城市用地管理中的应用,可为复杂社会—生态系统可持续发展提供路径指导。 相似文献
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Why GPS makes distances bigger than they are 总被引：1，自引：0，他引：1
Peter Ranacher Richard Brunauer Wolfgang Trutschnig Stefan Van der Spek Siegfried Reich 《International journal of geographical information science》2016,30(2):316-333
Global navigation satellite systems such as the Global Positioning System (GPS) is one of the most important sensors for movement analysis. GPS is widely used to record the trajectories of vehicles, animals and human beings. However, all GPS movement data are affected by both measurement and interpolation errors. In this article we show that measurement error causes a systematic bias in distances recorded with a GPS; the distance between two points recorded with a GPS is – on average – bigger than the true distance between these points. This systematic ‘overestimation of distance’ becomes relevant if the influence of interpolation error can be neglected, which in practice is the case for movement sampled at high frequencies. We provide a mathematical explanation of this phenomenon and illustrate that it functionally depends on the autocorrelation of GPS measurement error (C). We argue that C can be interpreted as a quality measure for movement data recorded with a GPS. If there is a strong autocorrelation between any two consecutive position estimates, they have very similar error. This error cancels out when average speed, distance or direction is calculated along the trajectory. Based on our theoretical findings we introduce a novel approach to determine C in real-world GPS movement data sampled at high frequencies. We apply our approach to pedestrian trajectories and car trajectories. We found that the measurement error in the data was strongly spatially and temporally autocorrelated and give a quality estimate of the data. Most importantly, our findings are not limited to GPS alone. The systematic bias and its implications are bound to occur in any movement data collected with absolute positioning if interpolation error can be neglected. 相似文献