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Geocoding urban addresses usually requires the use of an underlying address database. Under the influence of the format defined for TIGER files decades ago, most address databases and street geocoding algorithms are organized around street centerlines, associating numbering ranges to thoroughfare segments between two street crossings. While this method has been successfully employed in the USA for a long time, its transposition to other countries may lead to increased errors. This article presents an evaluation of the centerline‐geocoding resources provided by Google Maps, as compared to the point‐geocoding method used in the city of Belo Horizonte, Brazil, which we took as a baseline. We generated a textual address for each point object found in the city's point‐based address database, and submitted it to the Google Maps geocoding API. We then compared the resulting coordinates with the ones recorded in Belo Horizonte's GIS. We demonstrate that the centerline segment interpolation method, employed by the online resources following the American practice, has problems that can considerably influence the quality of the geocoding outcome. Completeness and accuracy have been found to be irregular, especially within lower income areas. Such errors in online services can have a significant impact on geocoding efforts related to social applications, such as public health and education, since the online service can be faulty and error‐prone in the most socially demanding areas of the city. In the conclusion, we point out that a volunteered geographic information (VGI) approach can help with the enrichment and enhancement of current geocoding resources, and can possibly lead to their transformation into more reliable point‐based geocoding services. 相似文献
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兰州市基本公共服务水平的区域差异分析 总被引：1，自引：0，他引：1
针对现有从乡(镇、街道)尺度研究基本公共服务水平空间差异较少的问题,该文以乡(镇、街道)为尺度,运用熵值法分析兰州市基本公共服务水平的空间差异。结果表明:得分最高酒泉路街道是得分最低哈岘乡的3.32倍,中等水平以下的区域占比为55.86%,说明空间差异较大且整体水平较低;较高和高水平区域沿铁路和公路成轴带状延展,而整体水平在东西和南北向均呈现出"n"形趋势;基本公共服务水平存在一定程度的空间关联,局部区域集聚效应显著;人口密度、经济和城市化水平均影响了基本公共服务的发展。研究结果可为相关政府部门推进兰州市基本公共服务均等化发展提供更加翔实的决策支持信息。 相似文献
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With the rapid development of social economy in Chengdu, it is of great significance to analyze the accessibility of a public facilities resources, and services in respective regions for the spatial planning of public facilities and the optimization of urban construction in Chengdu. Most existing studies only consider the accessibility of a single public facility under a single transportation mode studying facilities at the same level. In this research, with the consideration of all these factors mentioned above, an improved 3-step floating catchment area (3SFCA) model of multi-transportation modes is introduced to analyze the accessibility and spatial distribution of multiple types of public facilities under multiple traffic modes. The new model classifies the grade of public facilities and calculates the service accessibility of public facilities under the driving, public transport, cycling, and walking modes in the five dimensions of education, medical care, commerce, transportation, and leisure in the central urban areas of Chengdu. Through the comparative analysis of multiple models, we found that the improved 3SFCA can more accurately evaluate the accessibility of all dimensions of public facilities in central urban areas of Chengdu. The accessibility of compound public facilities in the central city is excellent. With the gradual expansion to the outward areas, the diversity and accessibility of compound public facilities gradually decreases. Furthermore, the accessibility distribution of public facilities in the study area is not balanced. The accessibility between the central urban areas and the marginal areas differs greatly and the spatial differentiation is substantial. 相似文献
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Cloud computing has been considered as the next-generation computing platform with the potential to address the data and computing challenges in geosciences. However, only a limited number of geoscientists have been adapting this platform for their scientific research mainly due to two barriers: 1) selecting an appropriate cloud platform for a specific application could be challenging, as various cloud services are available and 2) existing general cloud platforms are not designed to support geoscience applications, algorithms and models. To tackle such barriers, this research aims to design a hybrid cloud computing (HCC) platform that can utilize and integrate the computing resources across different organizations to build a unified geospatial cloud computing platform. This platform can manage different types of underlying cloud infrastructure (e.g., private or public clouds), and enables geoscientists to test and leverage the cloud capabilities through a web interface. Additionally, the platform also provides different geospatial cloud services, such as workflow as a service, on the top of common cloud services (e.g., infrastructure as a service) provided by general cloud platforms. Therefore, geoscientists can easily create a model workflow by recruiting the needed models for a geospatial application or task on the fly. A HCC prototype is developed and dust storm simulation is used to demonstrate the capability and feasibility of such platform in facilitating geosciences by leveraging across-organization computing and model resources. 相似文献
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城市教育资源分配问题一直是全社会关注的焦点问题,本文以城市中学的选址问题为研究对象,在考虑到新建中学与已有学校覆盖范围、与公共基础设施距离等经典选址问题的基础上,结合DEM数据、土地利用数据、降雨量数据等,创新性地排除了大坡度、容易被淹没等不适合建立学校的区域,提出了一种新的城市新建中学候选范围提取模型,为城市新建学校选址提供参考。基于该模型,本文利用Arc GIS平台实现北京市现有中学教育资源的空间分布分析,发现北京市的中学教育资源存在较严重的总量不足和分布不均衡现象,认为新建中学应该建在北京市延庆县西部、昌平区南部以及房山大庆区南部。 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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地理信息是城市信息资源共享的基础,以地理空间框架为基础,建设城市地理信息公共服务平台,对于整合城市信息资源、促进部门间数据共享、交换与业务协同,推动城市信息化发展及数字城市、智慧城市建设具有重要的意义。本文以贵阳市基础地理信息公共服务平台建设为例,详细介绍公共服务平台建设模式、内容,并对预期效益进行了分析,为其他公共服务平台的建设提供参考。 相似文献
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GPS技术已应用于静态、准动态、动态以及基础设施支撑下的实时动态测量中。GPS系统发展成多系统兼容的GNSS系统,区城CORS系统发展成全国统一的一个网,基础设施的完善促进了技术的进步。但在一些无法进行网络RTK作业地区的地铁、桥梁施工等高精度工程建设中,需要布设高精度控制网。如何利用现有的CORS系统资源,为这些地区的工程项目提供技术支持？本文针对该问题,利用已有的软硬件设施,开展了试验分析研究,提供了一套可行的解决方法。 相似文献
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Economic, legal, and public policy issues influencing the creation, accessibility, and use of GIS databases 总被引：1，自引：0，他引：1
DAVID W RHIND 《Transactions in GIS》1996,1(1):3-12
Rhind (1992) argued that government data policies and Intellectual Property Righr (IPR) considerations would play an increasingly large role in influencing the use of GIS. This has proved to be correct in general but the non-technical factors affecting data collection, supply, and price have become ever more complex. Indeed, one characteristic of the present situation is that it is now impossible to consider the legal, economic, and public policy issues in isolation. Consequently, this paper sets out to identify the interactions between them and the areas of conflict. It draws upon the literature of a much wider area than traditional GIS. This approach is essential because of two factors. The first is that GIS databases are presently of modest commercial value compared to some other data and hence key decisions on IPR, etc are being made outside our discipline. The second is that the nature of GIS databases is mutating rapidly through the wider use of multi-media and of the internet. It is concluded that the future is largely unpredictable in any detail since the interactions differ in different countries and at different moments in time. In many cases, however, revenue generation from sales or leasing of data or from services built upon data exploitation is likely to be a characteristic of both the public and the private sectors. Such charging has observable beneficial effects to set against the frequently claimed disadvantages, whether measured in financial, legal, or public access terms. 相似文献
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作为社会化媒体的重要类型,微博已经成为继新闻网站、论坛、博客之后,网络舆论生成的主要载体,＂微博问政＂成为热点和趋势,政务微博也成为政府信息公开、发布权威信息、提供公共服务、加强政民互动、引导网络舆论的重要平台。随着政务微博的快速发展,一系列新问题、新挑战也逐步显现。本文结合国土资源部政务微博的现状,就如何使用政务微博为民服务,提高政务微博应用水平,促进政务微博的健康发展,提升政府公信力,提出了对策建议。 相似文献
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城市公共服务设施优化配置是实现城市公共服务均等化的必要途径。近年来,时空大数据、智能决策与仿真等技术蓬勃发展,引发了城市公共服务设施配置模型研究的革命。基于以上时代背景,本文对城市公共服务设施优化配置模型的近期研究进展进行了总结和展望：①优化决策模型朝着精细化方向快速发展,优化决策目标将更加多元化;②多源地理大数据和时空数据挖掘方法的城市公共服务需求建模动态化;③多目标群智能优化算法使城市公共服务设施优化决策朝着智能化的方向发展。随着大数据、云计算、并行计算和人工智能等新技术在GIS领域的广泛应用与集成,城市公共服务设施优化配置模型将越来越朝着精细化和智能化的方向发展。 相似文献
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Shawky MANSOUR 《地球空间信息科学学报》2016,19(1):26-38
Much attention has been given to address public health policy in Saudi Arabia, particularly for the management, quality, and coverage issues. However, assessment of spatial patterns, distribution, and provision of public health services has been neglected. This paper analyzes the availability and accessibility of public health facilities across Riyadh Governorate, Saudi Arabia at the subnational level. Spatial and attribute data of public health facilities potentially have been analyzed using GIS to produce accurate measure of accessibility. The spatial pattern of service distribution was examined using average nearest neighbor. Distances from demand points (populations) to providers (facilities) were calculated for each district using near analysis. In addition, the ratios of public health facility to population were calculated to identify underserved and overserved areas. The findings clearly indicate that the spatial pattern of the distribution of public health facilities was significantly clustered (p value < 0.001) with Z-score of ?10.9. Several districts within the central parts of the governorate were identified as having a higher density of facilities, while most of districts that are located in the marginal parts exhibit very low density of health facilities. Overall, there was a considerable variation in the average distance from district centroids to health facilities. Substantially, less than half of the population (45.4%) living in 61 districts has access to public health facility within less than 1-km distance. In contrast, the greatest increase in distances was observed for 6% of population living in 38 districts. People that live in such districts need to travel long distances for public health care. The output of this analysis can assist policy-makers and authorities of Riyadh Governorate in planning public health delivery. 相似文献
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连续运行参考站(CORS)系统在城市管理中的应用 总被引：4，自引：0，他引：4
刘士宁 《测绘与空间地理信息》2009,32(5):6-8
连续运行参考站（Continuous Operating Reference Station,CORS）系统技术具有提供导航、定位、气象等数据服务的准确性和时效性,已经在测绘、气象、地震、海洋、国防、公安、交通等多个行业广泛应用,但是,如何建立一套统一、完整的应用服务管理体系,综合协调各行业和部门之间的资源共享,满足各行业对CORS系统精度要求,为城市管理和建设提供高效有力的保障,本文对此进行了探讨,并得出以下结论：CORS系统应由政府测绘行政主管部门牵头建设和统一管理维护,以城市基础地理信息中心为技术依托和服务运转枢纽,社会其他需求行业参与建设并负责管理本行业数据的应用及维护,通过市场运作保障CORS系统正常运行。 相似文献
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《International Journal of Digital Earth》2013,6(4):285-304
Abstract Several innovative ‘participatory sensing’ initiatives are under way in East Africa. They can be seen as local manifestations of the global notion of Digital Earth. The initiatives aim to amplify the voice of ordinary citizens, improve citizens' capacity to directly influence public service delivery and hold local government accountable. The popularity of these innovations is, among other things, a local reaction to the partial failure of the millennium development goals (MDGs) to deliver accurate statistics on public services in Africa. Empowered citizens, with access to standard mobile phones, can ‘sense’ via text messages and report failures in the delivery of local government services. The public disclosure of these reports on the web and other mass media may pressure local authorities to take remedial action. In this paper, we outline the potential and research challenges of a ‘participatory sensing’ platform, which we call a ‘human sensor web.’ Digital Africa's first priority could be to harness continent-wide and national data as well as local information resources, collected by citizens, in order to monitor, measure and forecast MDGs. 相似文献
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基于互联网的国土资源信息“申请—应答”服务系统构架 总被引：1，自引：0，他引：1
本文在分析当前国土资源信息服务模式的基础上,针对现有模式难以满足的国土资源信息服务需求,提出了国土资源信息"申请—应答"式服务模式,设计了一个基于互联网的国土资源信息"申请—应答"式服务系统,并成功应用于土地登记信息查询服务。 相似文献
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In recent years, the increase in the number of hurricanes and other costal hazards in the US pose a tremendous threat to the residents of coastal states. According to the National Hurricane Center, Florida is the most vulnerable coastal state to hurricanes. Mitigation policies have been formulated to reduce mortality and provide emergency services by evacuating people from the hazard zone. Many of these evacuees, particularly the elderly or lower income populations, rely on evacuation shelters for temporary housing. Because of the cost and limited use, evacuation shelters are almost exclusively dual use shelters where the primary purpose of the facility is for some other public function (e.g. school, hospital, etc.). In 2000, the estimated shortage of public shelter spaces in Florida was about 1.5 million. The purpose of this study was to rank the existing and candidate shelters (schools, colleges, churches and community centers) available in the state based on their site suitability. The research questions examined in this study include: (1) How many candidate shelters are located in physically suitable areas (e.g. not in a flood prone area, not near hazardous facilities, etc.)?; (2) How many existing shelters are located in physically un suitable areas, but in socially suitable areas (situated in areas with demand)?; (3) How many alternative existing and/or candidate shelters with high/very high physical suitability are located near physically un suitable existing shelters and thus, may be better choices for a shelter?; and (4) How many existing shelters located in physically un suitable areas are not near alternative existing and/or candidate shelters? A Geographic Information System‐based suitability model integrating Weighted Linear Combination (WLC) with a Pass/Fail screening technique was implemented for the 17 counties of Southern Florida. It was found that 48% of the existing shelters are located in physically unsuitable areas. Out of all the candidate shelters, 57% are located in physically unsuitable areas. For 15 of the existing shelters in unsuitable locations, no alternative candidate or existing shelter with medium to high physical suitability exists within 10 miles (16.1 km). 相似文献