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111.
Delineating travel patterns and city structure has long been a core research topic in transport geography. Different from the physical structure, the city structure beneath the complex travel-flow system shows the inherent connection patterns within the city. On the basis of taxi-trip data from Shanghai, we built spatially embedded networks to model intra-city spatial interactions and to introduce network science methods into the analysis. The community detection method is applied to reveal sub-regional structures, and several network measures are used to examine the properties of sub-regions. Considering the differences between long- and short-distance trips, we reveal a two-level hierarchical polycentric city structure in Shanghai. Further explorations of sub-network structures demonstrate that urban sub-regions have broader internal spatial interactions, while suburban centers are more influential on local traffic. By incorporating the land use of centers from a travel-pattern perspective, we investigate sub-region formation and the interaction patterns of center–local places. This study provides insights into using emerging data sources to reveal travel patterns and city structures, which could potentially aid in developing and applying urban transportation policies. The sub-regional structures revealed in this study are more easily interpreted for transportation-related issues than for other structures, such as administrative divisions.  相似文献   
112.
王莺鹤 《价值工程》2015,(10):85-87
对于球形单层网壳结构进行考虑初始缺陷的几何非线性的有限元分析即荷载-位移全过程分析。  相似文献   
113.
This article looks at successive attempts to create new spatial imaginaries around three estuary‐based city regions in England: the London–Thames Gateway, the Atlantic Gateway/Mersey Belt (Manchester and Liverpool), and Hull and the Humber ports. We develop a framework of analysis for new planning and regeneration spaces that takes forward debates on relational and territorial geographies, spatial imaginaries and the creation of new regional identities as governance objects. Specifically, we adopt a long‐term and comparative perspective that allows an examination of how successive efforts at regional building are both path‐dependent and context‐specific, as new approaches reflect emerging ideas about how best to construct successful regions in a changing global economy.  相似文献   
114.
The spatial spillovers of housing prices across regions are well documented by a large body of previous studies. This paper tries to investigate the dynamic (time-varying) evolution of spatial interactions and their underlying driving factors intensively. Using a recently developed Generalized Autoregressive Score (GAS) model, this paper examines the time-varying spatial spillovers of housing prices in 70 major and median cities of China from 2006 to 2019. We find that the GAS model can well capture the impact of time-varying critical events of Chinese real estate market on the whole. However, different regions display heterogeneous variation patterns over time. Further investigation shows that inter-regional labor mobility and trades are two major channels, accounting for 1.25% and 2.58% of the monthly standard deviations of spatial spillover effects from one city to another, respectively. We also characterize and distinguish between three time-varying patterns of spatial spillovers within different regions of China. Our results shed lights on the understanding of spatial spillovers across regional real estate markets across different city network structures within China.  相似文献   
115.
Small area estimation (SAE) entails estimating characteristics of interest for domains, often geographical areas, in which there may be few or no samples available. SAE has a long history and a wide variety of methods have been suggested, from a bewildering range of philosophical standpoints. We describe design-based and model-based approaches and models that are specified at the area level and at the unit level, focusing on health applications and fully Bayesian spatial models. The use of auxiliary information is a key ingredient for successful inference when response data are sparse, and we discuss a number of approaches that allow the inclusion of covariate data. SAE for HIV prevalence, using data collected from a Demographic Health Survey in Malawi in 2015–2016, is used to illustrate a number of techniques. The potential use of SAE techniques for outcomes related to coronavirus disease 2019 is discussed.  相似文献   
116.
从大气环境与城市竞争力的关联性入手,将大气环境风险、现状和治理纳入评价指标体系,基于组合权重的大气环境竞争力评价模型,对2013-2017年京津冀13个城市的大气环境竞争力水平进行了测评,并结合空间自相关分析和障碍度模型揭示了其空间效应及障碍因素。结果显示:京津冀城市大气环境竞争力存在明显的空间差异,呈"北部高、南部低、局部跳跃"格局,城市差距逐渐缩小;京津冀城市大气环境竞争力呈显著的空间集聚效应且存在正向相关性,空间分布格局相对稳定。  相似文献   
117.
This paper estimates a spatial autoregressive (SAR) model of price dispersion using publicly available internet bookselling data. It uses a semiparametric adaptive estimator that does not require the usual Gaussian assumption of maximum likelihood (ML) estimators. The results suggest that both price competition and seller heterogeneity are key drivers of the observed price dispersion. The paper finds that sellers with large sales volume, newly established sellers and US mainland states-based sellers tend to price lower. The identified significant spatial interaction is evidence of spatial price competition. Controlling for everything else, a seller asks a lower price when large sellers charge relatively high prices, which is also evidence of price-based selling and undercutting.  相似文献   
118.
This study examined the travel motivation of international students in Korea using the theory of travel career pattern (TCP). In particular, latent profile analysis (LPA) was applied to identify latent classes within international students. Based on the results, four latent profiles were derived and named “Core,” “Longing,” “Middle,” and “Veteran.” The results described the travel motivation and patterns across these four profiles to enhance the understanding of international students in the context of tourism. There were significant differences in travel patterns (i.e. travel companion and information sources) among the profiles segmented by motivation. This study has expanded travel motivation research by (a) applying TCP to an understudied population (i.e. international students in a non-English-speaking country); (b) comparing travel careers between the home country, Korea (i.e. a study abroad destination), and the third countries; and (c) highlighting LPA as a clustering tool to understand travel motivation.  相似文献   
119.
邵博  郭雨珏  刘煜  冯昊  叶翀 《科技和产业》2020,20(8):157-162
福州市作为“21世纪海上丝绸之路”核心区建设支点城市获得快速发展,各区县之间的经济联系逐步加深,区域经济格局不断演变。以福州市13个区县作为研究对象,测度“海丝”核心区建设实施前后各区县的经济潜力与经济联系强度,通过分析区域经济格局演变,对福州市在“海丝”背景下的经济发展方向提出建议,为今后加快建成支点城市提供参考。  相似文献   
120.
在旅游业高质量快速发展的背景下,全面厘清与掌握省域尺度范围各旅游节点在网络中的角色和地位,并解析其网络结构效应具有重大意义。针对现有研究因旅游流数据采集限制而较少对团队游空间结构研究的不足,基于云南省旅游包车客运信息,运用社会网络结合空间分析的方法,提取了云南省团队游网络空间结构特征,并对其聚散效应进行分析。结果表明:云南省团队游整体网络密度较小且淡旺季表现出相似特征,网络对各节点的旅游联系与合作影响尚未显现,暴露出云南省团队游旅游市场发展的不均衡;团队游网络外向中心势显著高于内向中心势,网络空间集聚趋势明显;通常具有较强外向中心性的旅游节点同时也具有较强内向中心性,表现出“集中—发散”的聚散规律;旅游节点的聚散效应表现为单个节点以圈层状向外递减形式发生,其扩散路径主要集中于文山—蒙自、景洪—思茅方向。整体上,云南省区域旅游业发展差异明显,应重点加强滇西南与滇西旅游区、滇中与滇东北旅游区的旅游资源开发与合作。  相似文献   
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