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分形理论在城市交通网络时空演变特征研究中的应用--以上海市为例 总被引：6，自引：0，他引：6
以上海城市交通网络为例，通过不同行政区域交通网络的分维值测算，研究了分形特征的空间变化；利用上海全域及典型行政区交通网络不同时代的分维，研究了分形特征的时间演化。结果表明，上海城市交通网络的分形特征在空间域上城区内域明显复杂于外域，在城市发展主轴方向上表现为由内向外分维测度值的降低；而在时间域，近期的交通网络分形复杂度明显高于早期，反映了城市发展与形态演化的时间过程。 相似文献
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《International Journal of Digital Earth》2013,6(8):798-813
ABSTRACTCities often have a substantial green infrastructure, which provides local ecosystem services that improve the quality of life of urban residents. These services should be explicitly addressed in urban development policies, and areas with insufficient vegetation and limited access to public green spaces should be identified. This paper presents two spatially explicit urban green indicators that are derived using remote sensing imagery, freely available map data and spatial analysis tools from open source geospatial libraries and commercial software. The first indicator represents proportional green cover (public as well as private) in the vicinity of each building within a city. The second indicator quantifies the proximity of public green spaces as walking distances from buildings to actual park entrances. A dasymetric mapping approach was used to take spatial variations in population density into account. This allows representing the indicators from the perspective of citizens instead of buildings, which may be more meaningful for deriving statistics at city level or at the level of neighbourhoods or administrative zones. The potential use of these indicators in a planning context is discussed on a case study carried out for the city of Brussels, Belgium. 相似文献
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The obesity epidemic and inequalities in access to food are prompting increasing numbers of food environment studies, which rely on secondary data sources for mapping. This article assesses the reliability of the two main food outlet data sources in France: the volunteered geographical information (VGI) collaborative map OpenStreetMap (OSM) and the national business register Sirene. Their information on food outlets was assessed through ground-truthing in the city-region of Montpellier. Sensitivity, positive predictive value, and concordance were computed for each database. We analyzed the socio-spatial variability of these measures according to households' income level. The sensitivity of Sirene is good and that of OSM moderate, while the opposite holds for positive predictive value, and the concordance of both OSM and Sirene is fair. Sirene provides more reliable data on deprived neighborhoods and OSM on wealthy neighborhoods. Caution is recommended regarding the classifications on which they are based, the time required to update the institutional database, and socially influenced contributions to VGI. 相似文献
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Bradley W. Lane 《Journal of Geographical Systems》2011,13(2):147-171
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. 相似文献
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社区是城市细胞和基层单位,其防灾减灾能力建设对构建城市安全体系有着极其重要的作用。本文借助于熵权-灰靶模型和GIS叠置分析技术进行社区减灾能力综合评价方法研究,首先从灾害风险评估能力、救援与保障能力等6个方面构建起包含30个二级指标的社区减灾能力评价指标体系。经过指标序列的影响空间和标准模式的构建、灰靶变换和靶心度分级,进行社区减灾能力分级评价。以苏州新区作为案例分析研究区,借助于ArcMap10.2软件得到该区域的社区减灾能力空间分布特征图。分析结果表明,研究区社区减灾能力总体上呈现东区较好,西区较弱,区域内社区减灾能力建设不平衡特征。研究区各街道和社区的灾害风险评估能力和灾害管理能力较好,工程防御能力总体分布不均衡,经济基础支撑能力、救援与保障能力、公众认知能力较差,说明社区综合减灾能力不足,今后应从单纯依赖减灾示范社区建设转变为加强社区综合减灾能力的内涵建设。 相似文献
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GIS空间分析功能在超市选址中的应用 总被引：5，自引：1，他引：4
选择科学有效的位置是超市经营发展的先决条件,地理信息系统依靠其强大的空间分析和可视化功能使超市选址更具直观性和科学性。本文通过对商业选址影响因素的分析,采用GIS的空间分析功能实现其对多要素指标的综合分析,做出运用GIS选址的方案,实现GIS在超市选址分析中的系统设计。 相似文献
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城市建成环境是人类赖以生存的人造环境,城市建成环境存量是指城市中建筑物和基础设施的材料质量。反演城市建成环境存量的空间分布,是数字城市建设的新方向,它能够帮助我们了解城市发展模式,更加有效管理城市资源和废弃物等,对发展城市循环经济、实现城市的可持续发展有着十分重要的意义。本文详细介绍了城市建成环境存量空间计算的3种方法（自上而下、自下而上和遥感计算方法）的理论基础和发展现状,总结了目前的几中方法都存在着过度依赖统计数据、无法兼顾研究区域大尺度和高空间分辨率等问题。在地理大数据时代,更多的数据源为存量的计算带来了新的研究方向。本文总结了新数据源的优势,并展望了结合地理大数据和机器学习方法的存量计算方法,为城市建成环境存量的空间计算提供了一种新的思路。 相似文献
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居民区生活便利度分析是城市研究的热点问题之一，对提升城市居民生活质量具有重要意义。城市空间中的居民活动主要发生在道路网络空间，加色法同位规则是一种网络空间同位模式可视化挖掘方法，避免了复杂的数学公式、算法及相关参数，具有形象直观的特点。鉴于此，本文利用加色法同位规则这一可视化数据挖掘手段，在表达空间交互的同时将数据挖掘的结果直接用于居民区生活便利度分析。以兰州市为例，进行居民区与其他14类城市基础设施之间位置关系的挖掘试验，全局分析与局部分析相结合，对不同区域的居民区生活便利度进行评价，以期为兰州市城市建设提供参考。结果表明：在兰州市，居民区与药店、超市、牛肉面馆等地理要素存在最强同位规则，与医院、火锅店存在较强同位规则，与商场、派出所、消防站无同位规则；居民区在整体上呈现多个宜居中心的分布特点，在区位上呈现便利度东高西低的分布特征。 相似文献
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公共地图服务的普及是人们步入数字生活、建设智慧城市的重要一步。如何准确地探测群体用户访问行为的时空聚集访问模式,将网络虚拟空间访问行为映射为现实世界行为,是提升公共地图服务和推动智慧城市建设的关键所在。探寻了群体用户访问公共地图服务产生的热点聚集区域的时间及空间规律,基于海量用户访问日志记录,结合分组分析、时间序列统计分析和时空三维图可视化方法,挖掘得出公共地图服务热点区域具有明显的以星期为单位的周期自相似特征,多数热点区域在周期内连续出现;基于箱形图和频率密度图的统计方法,分析得到热点区域间距在空间上呈“小间距多,大间距少”的聚集分布形态,且在不同的图层中热点区域间距分布迥异。公共地图服务用户访问时空规律揭示了用户行为意图,可将人类活动数字化,促进智慧城市建设中人地关系的发展。 相似文献
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Water-poverty relationships in the coastal town of Mbour (Senegal): Relevance of GIS for decision support 总被引：1，自引：0，他引：1
Néné Makoya Toure Alioune KaneJean François Noel Vincent TurmineValentin Nedeff Gabriel Lazar 《International Journal of Applied Earth Observation and Geoinformation》2012,14(1):33-39
Coastal area is always a zone with complex problems. Due to the attraction they exert, are facing many social problems. Therefore, a coastal city is usually a city with problems. Its extension, caused by the influx of people from different backgrounds, creates an increased demand for services. One of the problems frequently encountered, especially in Senegal, is access to water. The problem of access to water is poorly treated, without being correlated with the urban evolution, i.e. with increasing population and demand growth. The water resource is facing numerous complications such as the lack of integrated management, integration issues at the governance level, where the local factor is often forgotten.The town of Mbour, object of our study, does not come out of that lot, being an attractive coastal city, from an African country. This indicates the need for an integrated management oriented from local to a global basis and not vice versa. The study presented in this paper indicates that a large proportion of the population has not access to a verified drinking water system and uses water from wells or standpipes. Half of the surveyed population (50%) has no access to a water supply system. The water poverty map of the town overlaps with that of the general poverty excepting few neighborhoods. This means that even areas that are not affected by poverty have a very low or poor access to water, which so far remains the perverse effect of the reform of the Senegalese water sector in 1995. 相似文献
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段新民 《测绘与空间地理信息》2011,34(5):113-116
城市基础空间数据库是城市GIS的核心,而数据质量的高低又是数据库建设成功与否的关键。本文在分析城市空间数据的基本特征、数据的特点以及空间数据库中存在的误差来源基础上,结合广州市1∶10 000城市地图数据建库,详细论述了城市基础空间数据建库中进行质量控制的内容及方法。 相似文献
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空间数据挖掘是一种知识决策支持技术,本文以大型综合连锁超市为例,研究了空间分类挖掘方法在连锁超市选址预测中的应用问题。结合连锁超市定位理论,对实验数据进行了选择和处理。同时进行了基于关联的分类实验,得到指导和预测选址的知识,并对预测知识的准确性和可信度进行了检验,结果显示预测准确率和可信度较高。本文制定的挖掘方案可为连... 相似文献
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We estimate spatiotemporal models of average neighborhood single family home prices to use in predicting individual property prices. Average home-price variations are explained in terms of changes in average neighborhood house attributes, spatial attributes,
and temporal economic variables. Models adopting three different definitions of neighborhoods are estimated with quarterly
cross-sectional data over the period 2000–2004 from four cities in Southern California. Heteroscedasticity and autocorrelation
problems are detected and adjusted for via a sequential routine. Results of these models suggest that forecasts obtained using
city neighborhood average price equations may have advantage over forecasts obtained using city aggregated price equations.
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以清代兰州城为研究对象,分乾隆和光绪两个时期,通过对历史文献、古地图以及现代文献等资料进行分析,运用GIS技术,基本复原了古城兰州的城市格局,绘制了清代两个时期兰州的城市格局复原图,分析和总结了乾隆和光绪两个时期兰州城市空间格局特征和发展特征。结果表明:清代两个时期的兰州城总体格局一致,城池"内小外大,内方外凸",内城街道呈丁字形,郭城街道呈十字形,外出道路在东西南北方向各有一条;经济的发展和近代工业的兴盛,使光绪时期的兰州有了进一步的发展:内城客商会馆林立,郭城的城西北角和东关一带工厂聚集,此外,教育也由县文庙、府文庙等的官学为主转变为中学堂、小学堂、师范学堂、军事学堂、实业学堂等多种类型,呈现出多元化特征。 相似文献
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为了解决空间数据集成、检索和访问的问题,从数据提供者和数据使用者2个角度出发,提出了建立具有统一集成、检索和访问接口的空间数据访问组件。该组件针对数据提供者提供统一的集成接口,实现了以ArcSDE为例的空间数据引擎和以REST服务为例的Web Service引擎,建立了针对第三方空间数据引擎和Web Service空间数据源集成方法。该组件内部构建了空间数据处理模块和Web Service数据处理模块,与空间数据集成接口相互协作完成集成并处理空间数据源的任务。同时,针对数据使用者提供了空间数据检索和访问功能,在空间数据检索接口中实现了基于要素的检索方法,能对集成后的空间数据进行快速的查询检索,达到空间数据共享、访问的目的。 相似文献
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Juan Mariano Camarillo-Naranjo Natalia Limones-Rodríguez María Fernanda Pita-López Mónica Aguilar-Alba 《International Journal of Digital Earth》2019,12(4):394-414
This paper summarizes our work on building a data model and a geovisualization tool that provides access to global climate data: the Global Climate Monitor Web Viewer. Linked to this viewer, a complete set of climate-environmental indicators capable of displaying climate patterns on a global scale that is accessible to any potential user (scientists and laypeople) will be built and published using the same online application. The data currently available correspond to the CRU TS3.21 version of the Climate Research Unit (University of East Anglia) database – a product that provides data at a spatial resolution of half of a degree in latitude and longitude, spanning January 1901 to December 2012, on a monthly basis. Since January 2013, the datasets feeding the system have been the GHCN-CAMS temperature dataset and the Global Precipitation Climatology Centre (GPCC) First Guess precipitation dataset. Climatologists, hydrologists, planners and non-experts users such as media workers, policymakers, non-profit organizations, teachers or students, can access useful climatological information through the Global Climate Monitor system. 相似文献