A graph-based approach for the structural analysis of road and building layouts

A better understanding of the relationship between the structure and functions of urban and suburban spaces is one of the avenues of research still open for geographical information science. The research presented in this paper develops several graph-based metrics whose objective is to characterize some local and global structural properties that reflect the way the overall building layout can be cross-related to the one of the road layout. Such structural properties are modeled as an aggregation of parcels, buildings, and road networks. We introduce several computational measures (Ratio Minimum Distance, Minimum Ratio Minimum Distance, and Metric Compactness) that respectively evaluate the capability for a given road to be connected with the whole road network. These measures reveal emerging sub-network structures and point out differences between less-connective and more-connective parts of the network. Based on these local and global properties derived from the topological and graph-based representation, and on building density metrics, this paper proposes an analysis of road and building layouts at different levels of granularity. The metrics developed are applied to a case study in which the derived properties reveal coherent as well as incoherent neighborhoods that illustrate the potential of the approach and the way buildings and roads can be relatively connected in a given urban environment. Overall, and by integrating the parcels and buildings layouts, this approach complements other previous and related works that mainly retain the configurational structure of the urban network as well as morphological studies whose focus is generally limited to the analysis of the building layout.     

城市地价动态变化监测的空间分析方法研究

提出以土地交易样本作为监测样本进行城市地价变化监测与分析的新方法，通过时序监测样本的Voronoi图，分析城市土地市场的热点区域和发展趋势，采用主要交通干道作为特征剖面曲线对两个时点的地价变化值的等值线进行空间分析，确定地价突变区域作为城市基准地价更新资料调查的主要范围，并以武汉市2000～2003年的城市地价变化为例，分析验证了上述方法的可行性与合理性。     

A Comparative Analysis of Areal Interpolation Methods

Over the years many approaches to areal interpolation have been developed and utilized. They range from the simple 2-D areal weighing method which uses only the spatial Z variable being processed, to more sophisticated approaches which use auxiliary variable(s) to provide more specificity to the results. In the research reported here, four promising approaches are implemented and comparatively tested. These approaches have widely varying conceptual foundations, and different auxiliary variables, if used. The areal weighing reflects many earlier methods which assumes uniform distributions of the spatial Z variable, and does not use any auxiliary variable. Tobler's pycnophylactic method uses a volumetric preservation approach, which assumes spatial Z variable is heterogeneously distributed, but does not use any auxiliary variable. The traditional dasymetric method of Wright is used with remote sensing spectral data of land use. Xie's road network hierarchically weighted interpolation uses the road network as the auxiliary variable, and assumes that population density is related to the class of the road, and to the density of the road network. The research design implemented here uses Census population distributions at different levels in the hierarchy as the source and target variables analyzed. The source zone population is taken at the Census Tract level, and the target zones are specified at the Census Block Group level in the hierarchy. The first two tests use only the Census population Z data, and no auxiliary variables, whereas the next uses remotely sensed land use data as the auxiliary data variable, and the fourth test utilizes the road network hierarchy as the auxiliary variable. The paper reports on the findings from these tests, and then interprets them in a spatial setting in terms of accuracy and effectiveness. This research points to the network method as the most accurate of the areal interpolation methods tested in this research.     

StarBorn: Towards making in‐situ land cover data generation fun with a location‐based game

Data contributed by a large number of non‐experts is increasingly used to validate and curate land cover data, with location‐based games (LBGs) developed for this purpose generating particular interest. We here present our findings on StarBorn, a novel LBG with a strong focus on game play. Users conquer game‐tiles by visiting real‐world locations and collecting land cover data. Within three months, StarBorn generated 13,319 land cover classifications by 84 users. Results show that data are concentrated around users’ daily life spaces, agreement among users is highest for urban and industry land cover, and user‐generated land cover classifications exhibit high agreement with an authoritative data set. However, we also observe low user retention rates and negative correlations between number of contributions and agreement rates with an authoritative land cover product. We recommend that future work consider not only game play, but also how motivational aspects influence behavior and data quality. We conclude that LBGs are suitable tools for generating cost‐efficient in‐situ land cover classifications.     

北京环线建设驱动的土地利用变化遥感检测与分析

近年来,北京市的环线建设大大改进了北京的交通状况,促进了环线周边的商业发展和房地产开发的繁荣,同时也带来了环线周边地区的土地利用的变更。在“科技奥运”科技攻关项目和在研自然科学基金项目的支撑下,选择了1988,1994,2001和2003年5—6月份的TM数据,在影像经过几何校正和辐射归一化校正后对其应用高精度的自组织神经网络分类和利用高分辨率的航空照片验证;在分类数据和变更信息的基础上,采用了空间自相关分析模型、频率指数模型和潜力模型分别对北京各种用地类型的频率指数和建设用地的Moran系数和Geary系数,以及城市增长的潜力指她进行计算。一系列计算显示了环线驱动的北京市土地利用变化情况。结果表明:在环线建设的驱动下,北京市的建设用地围绕环线呈快速增长趋势;绿地面积在四环、五环的环线一带也呈增加趋势;城市增长潜力从四环到六环呈逐渐增大趋势。     

航拍图像跨数据域特征迁移道路提取方法

针对传统道路提取方法应用于新数据泛化能力不足的问题,研究了通过特征迁移和编解码网络实现跨数据域的道路提取方法。首先,构建了基于编解码网络的道路提取基本模型,用于实现单一数据来源的道路提取任务。然后,基于道路提取网络结构和循环一致性原则,提出了用于跨数据域图像特征迁移的循环生成对抗网络,使目标域图像映射入源域特征空间。使用预训练的道路提取模型处理特征迁移后的目标域图像,即可实现跨数据域道路提取任务。试验结果表明,本文所提方法能够拓展道路提取网络的泛化能力,准确有效地提取跨数据域图像中的道路目标。相较于未特征迁移的结果,本文所提方法大幅改善了道路提取指标,使得F1提升了50%以上。本文方法不需要目标域的标注信息,也不需要对道路提取网络进行微调训练,而只需训练由目标域向源域的特征迁移模型,所耗时间和人力成本较低,因而具有良好的应用价值。     

应用PSInSAR技术分析上海道路网沉降时空特性

城市道路网的持续稳定性监测不仅可以避免重大事故带来的人身财产损失,也有利于经济社会的可持续发展。针对道路网长距离、大跨度的实时监测需求,将永久散射体雷达干涉测量（persistent scatterer synthetic aperture radar interferometry,PSInSAR）技术引入城市道路网的形变监测和预警,处理了上海26景时间序列TerraSAR-X卫星数据,对道路网的沉降进行时空分析。空间上,首先阐述道路网整体的沉降格局,然后探讨局部路段的沉降细节及其驱动力;时间上,分析温度变化对路面沉降时间序列变化的影响,并对实验结果进行精度验证。结果表明,上海道路网沉降主要分布在浦东区,与路网密度相关,新区城市化发展建设已成为道路网主要的沉降原因;沥青路面的沉降时间序列与温度变化存在时间相关性,沉降结果与水准数据基本一致。     

运用复杂网络方法分析城市道路网的鲁棒性

道路网的鲁棒性分析有助于预防或者降低恐怖袭击、自然灾害以及交通拥堵造成的损失。从开放街道地图上获得世界范围内的50个城市道路网,沿用复杂网络鲁棒性分析方法,运用连续删除模型和级联模型对以道路链相交关系表示的城市道路网进行了鲁棒性分析,同时对路网的鲁棒性与其拓扑模式间的关系进行了探讨。研究发现,对于路网的鲁棒性,运用连续删除模型和级联模型所得到的鲁棒性结果存在差异。其中,连续删除模型的道路网鲁棒性普遍较差;而级联模型的鲁棒性,不同路网之间的差别较大;对于同一模型下的度策略和介数策略,介数策略的破坏性大于度策略。对于路网鲁棒性与其拓扑模式的关系,在连续删除模型下,路网鲁棒性与度相关性呈现显著正相关,无标度与非无标度的路网鲁棒性有差异;在级联模型下,路网鲁棒性与度相关性不相关,无标度与非无标度的路网鲁棒性差异不显著。     

采用层次分析法的道路网整体匹配方法

道路网变化较快,对其匹配和更新受到广泛关注。目前道路网匹配算法多集中于离散弧段间的匹配,匹配整体性不强,匹配精度不高。本文在分析道路匹配关系的基础上,借鉴人类认知客观世界从整体到局部的思想,对离散道路弧段通过Stroke模型进行聚合处理,然后采用线、面相对位置关系探测候选匹配集,进行道路筛选及整体匹配。针对当前匹配方法中各相似权值确定较为随意的问题,本文在分析各相似指标关系的基础上,借鉴层次分析法中的决策思维方式,对道路网匹配中的各相似指标进行定性和定量分析,并自动分配权值,进而根据获得的整体相似度来自动匹配。实验结果表明,采用层次分析法进行道路网整体匹配,可有效提高匹配效率、正确率及自动化水平。     

基于GIS的青岛市中心城区道路网络可达性研究

针对青岛市中心城区交通网络建设不完善的问题,研究了该区域路网的综合可达性,并提出了相应的解决方案。基于GIS平台,建立了青岛市中心城区路网模型;选取最小阻抗(时间和距离)、交叉口服务指数、路网密度和路网连通度作为关键评价指标,分别从路网距离关系、路网结构合理性、路网密度和路网发育程度4个方面分析了该区域的路网可达性;在此基础上,建立了青岛市中心城区路网综合评价模型。研究结果表明,该区域的路网以多中心多圈层形式分布,整体可达性良好;西南区域路网密度低,南部外围区域机动性差,南部地区可达性较差,应不断加强该地区的基础设施与路网建设。     

Network Density and the Delimitation of Urban Areas

This paper examines network analysis for urban areas. The research is focused on the problem of definition and visualisation of network geography and network spaces at different scales. The urban scale of analysis is examined and different spatial indices are considered. The built environment of the city is considered as a reference environment for a road network density index. The latter is implemented in order to study the spatial interactions between network phenomena and spaces and to provide further elements for the analysis of urban shape. The study is focused in particular on understanding spatial patterns drawn by networks and in helping with the delimitation of city centres. Different approaches are used to obtain the two indices: a grid–based analysis and a spatial density estimator based on Kernel Density Estimation. The two methodologies are analysed and compared using point data for the urban road network junctions and street numbers as house location identifiers in the Trieste (Italy) Municipality area. The density analysis is also used on road network junctions' data for the city of Swindon (UK) in order to test the methodology on a different urban area.     

基于复杂网络的城市道路重要度评价及路网自动综合方法

利用复杂网络理论,构建城市复杂路网模型,基于该模型从道路的结构和功能特征角度,以连接度、介中心和接近度为度量指标定义道路重要度评价模型,并顾及路网的整体形态及路网的拓扑连通性,提出基于复杂网络理论的路网综合算法。为检验方法有效性,针对成都市道路网络进行实验分析。实验结果表明,该道路重要度评价模型较好地反映道路在整个路网结构和功能上的重要程度,复杂路网综合算法能较好地保持原始路网的整体形态结构特征。     

The influence of sampling design on spatial data quality in a geographic citizen science project

Geographic citizen science has much potential to assist in wildlife research and conservation, but the quality of observation data is a key concern. We examined the effects of sampling design on the quality of spatial data collected for a koala citizen science project in Australia. Data were collected from three samples—volunteers (n = 454), an Internet panel (n = 103), and landowners (n = 35)—to assess spatial data quality, a dimension of citizen science projects rarely considered. The locational accuracy of koala observations among the samples was similar when benchmarked against authoritative data (i.e., an expert‐derived koala distribution model), but there were differences in the quantity of data generated. Fewer koala location data were generated per participant by the Internet panel sample than the volunteer or landowner samples. Spatial preferences for land uses affecting koala conservation were also mapped, with landowners more likely to map locations for residential and tourism development and volunteers less likely. These spatial preferences have the potential to influence the social acceptability of future koala conservation proposals. With careful sampling design, both citizen observations and land use preferences can be included within the same project to augment scientific assessments and identify conservation opportunities and constraints.     

一种道路网三维建模方法

针对道路网三维建模中成本高、周期长等问题,该文介绍了一种基于规则的道路网三维建模方法。在规则文件驱动下,该方法充分考虑道路网的结构化特征和地理环境,利用抽象化的道路网实体数据和属性信息,实现批量化道路网建模,并在云平台上发布,进而实现道路网三维景观的浏览、查询和分析。采用上述方法实现了一段包含立体交叉在内的道路网的三维模型的快速搭建。结果表明,该方法的规则复用性强、建模效率高、模型调整速度快,为在三维GIS环境下构建道路网模型提供了高效的技术手段。     

重庆市房价与地价影响因素实证研究

房价与地价的影响因素多且因素之间相关关系复杂,本次研究通过收集整理重庆市房价与地价的相关数据,采用政策因素、宏观区位因素、微观区位因素、平均容积率因素、规划因素、路网密度因素来研究房价与地价之间的关系,通过建立因素间的通径图构建房价地价的结构方程模型,详细分析了各因素之间的影响关系.     

Road hierarchy with integration of attributes using fuzzy-AHP

Road objects in a network data model are categorised into a hierarchical structure in accordance with their functions and capacities. In this study; five road attributes derived from semantic, geometric and topological properties of network data set (i.e. road class, road length and centralities of degree, closeness and betweenness) are utilised for the creation of road network hierarchy. The relationships with each attributes except road class and their effects on the determination of road importance are analysed by using a distribution graph and the equation of Pearson correlation coefficient. For creating road network hierarchy, integration process is achieved through the application of fuzzy analytic hierarchy process assuming attributes as the fuzzy criteria. The integration process is followed by the calculation of new priority attribute that indicates the importance of road objects. At the end of the process, road class, which is the most important attribute, is also used for the validation of proposed methodology. The results show that the new priority value of a road is superior to its each attribute value in hierarchical organisation.     

利用Minkowski距离逼近道路网络距离算法研究

道路网络背景下的距离度量（如道路网络距离、旅行时间）是在空间分析或空间统计过程中常用的距离度量,但在科研过程中由于道路数据的可获得性和精度等方面的限制,该类距离的计算可能较为困难。Minkowski距离函数是欧氏空间中的广义距离函数,其参数p值的不同代表着对空间不同的度量。利用Minkowski的通用性和灵活性（参数p不同的取值）,研究如何更好地逼近道路网络距离。同时,探索不同道路网络的部分计量特征（如密度、弯曲度等）与最优p值之间的关系。实验证明,相对于最常用的欧氏距离度量,优选p值后的Minkowski距离函数能够更大程度上逼近道路距离。而通过对道路网络计量特征与最优p值之间的关系的分析,指出了弯曲度与最优p值之间的对应关系,它对于p值的选择具有重要的指导意义。此外,为了验证Minkowski距离逼近算法的可行性,以地理加权回归分析为例,通过对比传统的欧氏距离度量、最优Minkowski距离度量和道路网络距离（旅行时间）对模型解算结果的影响,指出优选后Minkowski距离一定程度上更接近于采用旅行时间对模型解算的结果。     

城市轨道站点拓扑网络通达性建模及分析

通过研究交通网络的空间连接及由此决定的节点间联系的连通程度,可观测交通可达性水平。本文对地下轨道交通和地面道路交通构成的立体拓扑网络进行了建模,采用空间句法形态分析变量构建了基于轨道站点的通达性模型,分析了深圳市轨道站点通达性水平和空间特征,并探讨了站点通达性与周边土地利用的相互关系。研究结果表明,深圳市轨道站点通达性平均值为0.088 4,通达性数值离散程度较低,在空间上形成了福田中心区、华强北商业区、东门商业区和后海片区4个高值热点区;商业用地、办公用地与站点通达性的相关程度最大,工业仓储用地受轨道站点的影响较小,轨道站点倾向于商业及办公用地等人流量集中的空间节点;轨道站点基本可承载周边的土地开发,组合类型为"高-中""中-低"的27个站点需提升综合立体交通体系功能。笔者从拓扑网络耦合的思路,客观评价了深圳市轨道站点通达性及其与土地利用的相互关系,提供了研究对象由线路向站点转换的研究视角,可为同类研究提供参考意义。     

集成暴雨洪水管理模型的带权雨水网络构建

针对城市雨水网络传统规划手段落后导致城市地面雨水不能及时有效地收集和排除的问题,该文提出了基于GIS和暴雨洪水管理模型(SWMM)集成的带权雨水网络的构建方法。通过软件互操作模式将SWMM模型封装成.NET托管动态库,实现了其与GIS空间分析组件的无缝集成;以新城区竖向设计高程和规划路网为基础数据,构建顾及路网的格网DEM;基于新城区规划用地类型和研究区暴雨模型,运用GIS空间分析实现了水文参数的自动提取;进一步率定雨水管网权重因子,利用GIS几何网络分析实现了带权有向雨水网络自动构建及布局优化。实验结果表明:该方法较传统方法工作效率更高,且布网方案、雨水出口选择、管力计算等方面更加科学合理。     

Methodology of Maintenance Criteria of PMGSY Roads in Second Phase of Planning-A Case Study

Present paper focuses on the development of a planning model for upgradation of rural roads keeping Pradhan Mantry Gram Sadak Yoyna (PMGSY) program as the base of this model. Database for the PMGSY roads of Gandevi block of Navasari district in Gujarat state is prepared which includes data like village data, road network & traffic data. Core network is prepared for all the villages under study which can be defined as rural network required for providing ‘basic accesses to all villages. i.e. all villages are connected nearby market centre and essential places from all weather roads. Planning model is classified in two phases. First phase is the network planning and the second phase is upgradation of roads. For the network planning utility values of the villages is calculated by using Delphi technique and on the basis of that alternative routes are decided. For the upgradation of existing roads, Pavement Condition Index (PCI) value of each road is determined and based on these values upgradation of roads are priorities. The rural road network planning methodology for PMGSY roads based on the accessibility concept is presented in this paper and implemented using Geographic Information System (GIS) technology.