青岛市城市轨道交通线路网络复杂特性分析

运用复杂网络理论,分别在Space-L和Space-P两种拓扑空间下构建青岛市规划至2020年的城市轨道交通线路网络。通过计算两种空间模式下的网络度分布、平均最短路径、聚类系数等统计特征指标进行对比分析。研究表明:青岛市规划至2020年的城市轨道交通网络具有小世界网络特征,线路交错程度不高,站点间的可达性程度为中等。从复杂网络角度观察城市轨道交通,旨在发现青岛市城市轨道交通内在特点,为青岛市轨道规划管理部门提供辅助性参考意见。     

A generic space definition framework to support seamless indoor/outdoor navigation systems

Contemporary public buildings are becoming conglomerates of open, semi‐open and closed spaces, with indoor, outdoor and underground sections. For humans and robots to navigate seamlessly through such environments, new flexible approaches need to be developed. Navigation systems generally rely on a network (nodes and edges) as an abstraction of underlying space availability. However, indoor and outdoor networks have different origins. While indoor systems rely on indoor space subdivision approaches, current outdoor systems utilize road‐based network approaches. Linking such networks via particular nodes is possible but restrictive. Many spaces in the built environment are not strictly indoor or outdoor spaces and are thus often omitted from navigation networks, further limiting navigation options. To overcome these shortcomings, we introduce a new space definition framework in which the entire built environment is categorized into indoor, outdoor, semi‐indoor and semi‐outdoor spaces. We provide strict definitions for the four space categories. Our framework allows the same navigation network extraction approaches to be used and therefore enables seamless indoor/outdoor path computation for single or combinations of locomotion modes. The notions of semi‐indoor and semi‐outdoor spaces offer new options for further tailoring of the navigation path with respect to environmental factors, which we demonstrate with two use cases.     

Exploring the link between urban form and work related transportation using combined satellite image and census information: Case of the Great lakes region

Aspects of urban transportation have significant implications for resource consumption and environmental quality. The level of travel activity, the viability of various modes of transportation and hence the level of transportation-related emissions are influenced by the structure of cities, i.e., their urban forms. While it is widely recognized that satellite remote sensing can provide spatial information on urban land cover and land use, its effective use for understanding impacts of urban form on issues such as transportation requires that this information be integrated with relevant demographic information. A comprehensive bi-national urban database, the Great Lakes Urban Survey (GLUS), comprising all cities with populations in excess of 200,000 has been created from Landsat imagery and national census and transportation survey information from Canada and the United States. A suite of analysis tools are proposed to utilize information sets such as GLUS to investigate the link between urban form and work-related travel. A new indicator, the Employment Deficit Measure (EDM), is proposed to quantify the balance between employment and worker availability at different transit horizons and hence to assess the viability of alternate modes of transportation. It is argued that the high degree of residential and commercial/industrial land uses greatly impact travel to work mode options as well as commute distance. A spatial interaction model is developed and found to accurately predict travel distance aggregated at the census tract level. We argue that this model could also be used to explore the relative levels of travel activity associated with different urban forms.     

Multi‐temporal transport network models for accessibility studies

Vehicle tracking is a spatio‐temporal source of high‐granularity travel time information that can be used for transportation planning. However, it is still a challenge to combine data from heterogeneous sources into a dynamic transport network, while allowing for network modifications over time. This article uses conceptual modeling to develop multi‐temporal transport networks in geographic information systems (GIS) for accessibility studies. The proposed multi‐temporal network enables accessibility studies with different temporal granularities and from any location inside the city, resulting in a flexible tool for transport and urban planning. The implemented network is tested in two case studies that focus on socially excluded people in a large global city, São Paulo, Brazil, including accessibility analyses from slum areas. It explores variations within a day and differences between transport modes across time. Case study results indicate how the accessibility is heterogeneous in low‐income regions.     

武汉市轨道交通4号线二期工程GPS控制网的建立及精度分析

介绍武汉市轨道交通4号线二期工程GPS控制网的设计、外业观测和数据处理,分析本次GPS控制网的成果精度,并就GPS技术在城市轨道平面控制测量中的应用提出有益的意见.     

基于InSAR的城市地下轨道交通沉降与灾害监测

城市地铁建设会对邻域造成地质环境损伤，甚至发生灾变。传统基于点位测量的方法在实际应用过程中存在野外作业周期长、受天气影响及耗费大量人力物力等缺点。因此，本文基于城市地下轨道交通安全施工中的应用需求，以天津市地铁五号线为例，利用27景TerraSAR数据和PS-InSAR时序监测方法，对地下轨道交通地铁站和隧道施工影响进行了监测和评估。结果表明，PS-InSAR能在施工期间监测到地铁线及周边的形变，有利于城市轨道交通全生命健康监测。     

A spatiotemporal analysis of metro-stop based accessibility to bus services in Shanghai,China

Ground-level bus offers flexible services with relatively inexpensive fares and high-level accessibility, thus is the dominant feeder mode for metro in the majority of metropolitan areas in China. Intermodal transfer between the metro and bus networks is therefore a crucial element in the successful operation of an integrated transit system. In this circumstance, a key challenge is lack of appropriate methodologies to evaluate the spatial–temporal disparities of intermodal transfers between metro and bus. To address this issue, this research aims to promote an existing two-step floating catchment area (2SFCA) model by incorporating the temporal variability of service supply, demand, and travel time to provide a more realistic estimation of accessibility using smart card data and automatic vehicle location data. The proposed methodology was applied in a case study of the metropolitan area of Shanghai in the specific context of metro-stop based accessibility to bus services. The results of the case study show that the daily fluctuations in output metro-to-bus transfer accessibility values are highly sensitive to temporal dynamics of transfer time, service supply, and demand. It is hoped the results output here could give planners and policymakers greater insight into spatiotemporal dynamics on transfer accessibility, and help to establish an effective and efficient integrated transit system.     

地铁网络可达性时空演化及空间形态分析

针对广州地铁网络的可达性空间特征及产生的区域响应,该文基于图及可达性测度模型,结合GIS技术,探讨其时空发育状况、拓扑结构、可达性演变与区域差异特征。结果显示,广州地铁网络与商住区的空间扩张过程在时空上吻合;广州地铁网络逐步演化为回路网络,但拓扑结构存在不足;时间可达性重心从政治中心向商业中心转移,可达性从商业中心向四周区域辐射,并随距离逐渐衰弱;可达性空间模式存在着明显的区域差异,换乘站点对所在区域的可达性作用显著;潜力可达性空间分布形态呈现双中心特征,且在空间分异上与城市交通发展水平相呼应。通过对广州地铁网络进行可达性演化和空间特征分析,既为交通可达性研究提供实践经验,也为地铁网络发展决策提供理论参考。     

集成多源地理大数据感知城市空间分异格局

多源地理大数据为地理现象的分布格局、相互作用及动态演化提供了前所未有的社会感知手段。城市是人类活动最为集中的区域,产生了多种地理大数据,并支持对于城市空间的理解。城市内部的分异格局是城市研究和规划所要面对的重要议题,社会感知数据提供了从"人-地-静-动"4个维度刻画城市分异格局的途径。梳理了不同类型大数据对于表达这4个维度特征的支持,并借鉴"生态位"模型,通过一个实例研究展示了集成多源数据量化城市空间分异特征的应用,最后讨论了相关的理论问题。     

Knowledge Transfer for Large‐Scale Urban Growth Modeling Based on Formal Concept Analysis

Cellular automata (CA) are useful for studies on urban growth and land‐use changes. Although various methods have been developed to define transition rules, modeling urban growth of large areas remains a tough challenge owing to heterogeneous geographical features. To address the problem, we present a novel method based on the combination of Formal Concept Analysis (FCA) and knowledge transfer techniques. FCA is used to solicit association rules among cities within a large area. This method can provide a theoretical basis for the knowledge transfer process. A cutting‐edge algorithm called TrAdaBoost is then integrated with the commonly‐used Logistic‐CA as the modeling framework. The proposed method is applied to the urban growth modeling of Guangdong Province, a large region with 21 cities in China, from 2005 to 2008. Compared with traditional methods, this method can achieve better results at the provincial and local levels, according to the experiments. The combination of FCA and knowledge transfer is expected to provide a useful tool for calibrating large‐scale urban CA models.     

高分辨率PS-InSAR在轨道交通形变特征探测中的应用

为了确保城市轨道交通的安全运营和可持续发展,将高分辨率PS-InSAR技术引入城市轨道交通的形变监测领域。以上海为例,分析了城市轨道交通网络专题的形变特征。首先,利用26景TerraSAR-X影像在上海开展高分辨率PS-InSAR沉降精细测量,得到轨道交通网络整体的沉降格局;然后,针对不同建成时期和建设形式的路段,分类探讨其形变特性及原因;最后,进行测量结果的精度验证。分析结果表明,快速的城市化发展建设已成为上海轨道交通沿线主要的沉降原因;不同建成时期和建设形式的路段表现出不同的形变特征,早期建设路段比晚期建设路段更稳定,高架路段比地下路段沉降速率更小;PS-InSAR与水准数据保持很好的一致性。证实了高分辨率PS-InSAR技术在城市轨道交通形变监测、管理维护和预警方面具有一定的可行性,可以为城市公共交通的规划和建设提供决策支持。通形变监测、管理维护和预警方面具有一定的可行性,可以为城市公共交通的规划和建设提供决策支持。     

Assessing the effect of temporal dynamics on urban growth simulation: Towards an asynchronous cellular automata

Time is a fundamental dimension in urban dynamics, but the effect of various definitions of time on urban growth models has rarely been evaluated. In urban growth models such as cellular automata (CA), time has typically been defined as a sequence of discrete time steps. However, most urban growth processes such as land‐use changes are asynchronous. The aim of this study is to examine the effect of various temporal dynamics scenarios on urban growth simulation, in terms of urban land‐use planning, and to introduce an asynchronous parcel‐based cellular automata (AParCA) model. In this study, eight different scenarios were generated to investigate the impact of temporal dynamics on CA‐based urban growth models, and their outputs were evaluated using various urban planning indicators. The obtained results show that different degrees of temporal dynamics lead to various patterns appearing in urban growth CA models, and the application of asynchronous (event‐driven) CA models achieves better simulation results than synchronous models.     

Fine‐scale intra‐ and inter‐city commercial store site recommendations using knowledge transfer

The rapid development of urban retail companies brings new opportunities to the Chinese economy. Due to the spatiotemporal heterogeneity of different cities, selecting a business location in a new area has become a challenge. The application of multi‐source geospatial data makes it possible to describe human activities and urban functional zones at fine scale. We propose a knowledge transfer‐based model named KTSR to support citywide business location selections at the land‐parcel scale. This framework can optimize customer scores and study the pattern of business location selection for chain brands. First, we extract the features of each urban land parcel and study the similarities between them. Then, singular value decomposition was used to build a knowledge‐transfer model of similar urban land parcels between different cities. The results show that: (1) compared with the actual scores, the estimated deviation of the proposed model decreased by more than 50%, and the Pearson correlation coefficient reached 0.84 or higher; (2) the decomposed features were good at quantifying and describing high‐level commercial operation information, which has a strong relationship with urban functional structures. In general, our method can work for selecting business locations and estimating sale volumes and user evaluations.     

区域沉降对城市轨道交通建设的影响及应对措施

当轨道交通穿越沉降漏斗区和沉降带时,会对城市轨道交通线路的建设及运营产生非常大的破坏影响。为使测量技术更好地为城市轨道交通工程建设服务,本文以北京地铁14号线工程建设的实际测量作业为背景,通过分析、研究与总结,从高程贯通误差公式设计依据、地面沉降对高程贯通误差的影响、考虑地面沉降的高程贯通误差计算、建设阶段实际地面沉降影响及应对措施等几个部分进行阐述。区域沉降对城市轨道交通建设的影响及应对措施是在工程实践中通过研究分析得出的成果,对今后我国各城市的城市轨道交通工程建设的测量具有参考和指导意义。     

雷达技术支持下的福州市地铁沿线形变监测

近年来,由于地铁等地下工程大规模的建设产生了严重的地表沉降,从而诱发许多地质灾害,严重阻碍了中国城市化进程。因此,采用高精度雷达监测技术,对城市地质灾害监测及风险评估具有重要意义。本文利用SBAS-InSAR技术,基于24景X波段TerraSAR数据和32景C波段Sentinel-1数据,时间跨度分别为2013年7月至2015年8月、2015年7月至2018年2月,对地铁建设完成后的福州市区地表沉降进行长时间系列形变监测。监测结果表明,研究区域内的最大沉降速率为-12 mm/a,在整个观测周期内发现了8个沉降漏斗。并对这些区域进行进一步的时间序列分析,其中有3个区域呈现出地质灾害初期的特征,并且地表沉降存在进一步加剧的可能。     

A multi‐modal transportation data‐driven approach to identify urban functional zones: An exploration based on Hangzhou City,China

Recent urban studies have used human mobility data such as taxi trajectories and smartcard data as a complementary way to identify the social functions of land use. However, little work has been conducted to reveal how multi‐modal transportation data impact on this identification process. In our study, we propose a data‐driven approach that addresses the relationships between travel behavior and urban structure: first, multi‐modal transportation data are aggregated to extract explicit statistical features; then, topic modeling methods are applied to transform these explicit statistical features into latent semantic features; and finally, a classification method is used to identify functional zones with similar latent topic distributions. Two 10‐day‐long “big” datasets from the 2,370 bicycle stations of the public bicycle‐sharing system, and up to 9,992 taxi cabs within the core urban area of Hangzhou City, China, as well as point‐of‐interest data are tested to reveal the extent to which different travel modes contribute to the detection and understanding of urban land functions. Our results show that: (1) using latent semantic features delineated from the topic modeling process as the classification input outperforms approaches using explicit statistical features; (2) combining multi‐modal data visibly improves the accuracy and consistency of the identified functional zones; and (3) the proposed data‐driven approach is also capable of identifying mixed land use in the urban space. This work presents a novel attempt to uncover the hidden linkages between urban transportation patterns with urban land use and its functions.     

A Network Model for Dispersion of Communicable Diseases

The spread of communicable diseases through a population is an intrinsic spatial and temporal process. This paper presents an individual‐based analytical framework for modeling the spatial and temporal heterogeneity in the disease transmission. The framework specifies a network model structure and six associated parameters. These parameters describe the properties of nodes, the properties of links, and the topology of the network. Through this model structure and associated parameters, this framework allows the representation of discrete individuals, individualized interactions, and interaction patterns in a network of human contact. The explicit representation of the spatial distribution and mobility of individuals in particular facilitates the modeling of spatial heterogeneity in the disease transmission.     

移动三维激光测量系统在地铁运营隧道病害监测中的应用研究

随着我国轨道交通建设事业的蓬勃发展，三维地理信息系统在地铁隧道相关的竣工测量、变形监测等方面逐步得到应用，越来越受到地铁工程建设和管理部门的重视。由于地铁隧道工程的复杂性，采用传统方法进行运营隧道监测需要花费大量的人力、物力和时间。为了适应地铁建设和运营管理部门对地铁工程信息化、三维可视化工作的迫切要求，本文提出了一种集成多种传感器于一体的移动三维激光测量系统。该系统集成了高精度三维扫描仪及编码器等传感器，能快速、高精度地获取隧道内轮廓断面尺寸，通过配套的软件处理，高效地对限界、断面轮廓及隧道变形进行分析。通过在实际项目中应用验证表明，该方法能有效地解决地铁隧道病害监测中的实际问题，可供同类地铁工程项目参考借鉴。     

Spatio-temporal analysis of urban growth in selected small,medium and large Indian cities

This study attempts to ascertain the spatial and temporal variations in the evolution of Indian cities using multi-date remote sensing data. A two-stage object-based nearest neighbour classification approach with hierarchical segmentation was used to extract built-up area in selected small, medium and large cities, whereas object-based temporal inversion was applied for change analysis. The temporal trend of net population density, degree of scattered development and compactness of urban core in each city was determined using the built-up area. The study observed a declining trend in growth rate of built-up area in small and medium sized-cities, in contrast to large cities. However, the net population density in cities of all types is decreasing as urban growth has outpaced the corresponding population growth. Furthermore, small and medium cities indicated greater tendency for scattered development in comparison to large cities, whereas the core urban areas of the later appeared relatively less compact.     

TAZ-level variation in work trip mode choice between 1990 and 2000 and the presence of rail transit

Rail transit continues to be a popular alternative for cities as a tool for alleviating automobile congestion and for redeveloping areas into transit and pedestrian-friendly environments. Ideally, rail transit will draw trips away from cars, but the quantitative work that tests this notion has often been either case studies of neighborhoods, in which conclusions are tough to generalize, or citywide comparisons where important spatial variation is lost in aggregation. This study seeks to narrow this gap in the research by using multivariate analysis of covariance to isolate the effect of covariates and cities on changes in work trip mode choice at the traffic analysis zone (TAZ) level for nine cities between 1990 and 2000. The results suggest differences by city in the change at the TAZ level of the proportion of people driving alone and taking transit. Increases in transit usage were associated with cities that built rail transit, while increases in automobile commuting and decreases in transit usage were associated with cities that did not.