加拿大地理信息产业发展基础与现状研究     

孙威  管谌  曹会超 《测绘与空间地理信息》2017,40(5)

从地理信息管理、空间基础设施、地理信息产业发展情况等方面介绍了加拿大地理信息产业发展的现状,并分析加拿大地理信息产业发展的特点,提出促进我国地理信息产业健康快速发展的对策、建议。  相似文献   

Extracting and analyzing semantic relatedness between cities using news articles   总被引：1，自引：0，他引：1  

Yingjie Hu  Xinyue Ye  Shih-Lung Shaw 《International journal of geographical information science》2017,31(12):2427-2451

News articles capture a variety of topics about our society. They reflect not only the socioeconomic activities that happened in our physical world, but also some of the cultures, human interests, and public concerns that exist only in the perceptions of people. Cities are frequently mentioned in news articles, and two or more cities may co-occur in the same article. Such co-occurrence often suggests certain relatedness between the mentioned cities, and the relatedness may be under different topics depending on the contents of the news articles. We consider the relatedness under different topics as semantic relatedness. By reading news articles, one can grasp the general semantic relatedness between cities; yet, given hundreds of thousands of news articles, it is very difficult, if not impossible, for anyone to manually read them. This paper proposes a computational framework which can ‘read’ a large number of news articles and extract the semantic relatedness between cities. This framework is based on a natural language processing model and employs a machine learning process to identify the main topics of news articles. We describe the overall structure of this framework and its individual modules, and then apply it to an experimental dataset with more than 500,000 news articles covering the top 100 US cities spanning a 10-year period. We perform exploratory visualizations of the extracted semantic relatedness under different topics and over multiple years. We also analyze the impact of geographic distance on semantic relatedness and find varied distance decay effects. The proposed framework can be used to support large-scale content analysis in city network research.  相似文献   

印度地理信息产业发展基础与现状研究   总被引：1，自引：0，他引：1  

刘利 《测绘与空间地理信息》2016,(11):6-9

主要从地理信息资源生产管理体制、空间基础设施建设、产业政策3个方面分析了印度地理信息产业发展基础,并对当前印度地理信息产业规模、市场、企业、人才培养以及发展潜力等方面的现状进行了研究,对比我国分析了当前印度地理信息产业发展的优势和存在的制约。  相似文献   

城市地理空间数据集成应用探讨   总被引：1，自引：0，他引：1  

张衡  徐青  古林玉  王晓理 《测绘科学》2016,41(9):176-180

城市地理空间数据是表达城市地理要素的数量、质量、分布特征、相互关系、变化规律的位置信息和属性信息。分析城市地理空间数据的组成结构、组织管理、集成利用,并将这些数据有效应用于城市地理信息系统建设之中,将在城市信息化道路上起到举足轻重的作用。该文以开发的"兰州市城关区地理信息集成系统"为例,重点阐述了城市地理空间数据的构成与获取方式,研究了城市地理空间数据与业务部门数据的集成方法,并对城市地理空间数据在晕渲图制作、三维景观生成、数据可视化等主要应用上进行了分析和探讨。  相似文献   

广东西江流域地名调查工作特点与实例分析     

周羽 《测绘与空间地理信息》2016,(4):212-214

地名调查工作涉及地域划分,地理空间,语言文化,历史文化等方面,运用"3S"技术,结合当地语言文化开展此项工作,能提高调查工作效率和准确度,有利于对存在尚未掌握的地理实体及地名信息的判断、界定和甄别。通过广东郁南县地名调查工作实例,探讨在"3S"技术背景下,根据具有地域性文化特征地区的地名调查工作所呈现的新问题、新特点,可作范例为粤语地区的地名调查提供可操作性建议。  相似文献   

面向地理空间框架建设的城市大比例尺数据整合改造研究与实践     

佘安娜 《测绘与空间地理信息》2016,(12):170-172

城市大比例尺基础地理信息数据蕴含了丰富的信息,是其他信息空间化、标准化处理的基础和空间依据,是数字城市地理空间框架建设的重要组成部分。本文以福建省明溪县为例,讨论了城市大比例尺数据整合改造方法的研究,以及数据制作过程中所遇技术难题的解决办法,探索了一条高效可行的城市大比例尺数据改造方法。  相似文献   

A land use/land cover change geospatial cyberinfrastructure to integrate big data and temporal topology     

Jin Xing  Renee E. Sieber 《International journal of geographical information science》2016,30(3):573-593

ABSTRACT

Big data have shifted spatial optimization from a purely computational-intensive problem to a data-intensive challenge. This is especially the case for spatiotemporal (ST) land use/land cover change (LUCC) research. In addition to greater variety, for example, from sensing platforms, big data offer datasets at higher spatial and temporal resolutions; these new offerings require new methods to optimize data handling and analysis. We propose a LUCC-based geospatial cyberinfrastructure (GCI) that optimizes big data handling and analysis, in this case with raster data. The GCI provides three levels of optimization. First, we employ spatial optimization with graph-based image segmentation. Second, we propose ST Atom Model to temporally optimize the image segments for LUCC. At last, the first two domain ST optimizations are supported by the computational optimization for big data analysis. The evaluation is conducted using DMTI (DMTI Spatial Inc.) Satellite StreetView imagery datasets acquired for the Greater Montreal area, Canada in 2006, 2009, and 2012 (534 GB, 60 cm spatial resolution, RGB image). Our LUCC-based GCI builds an optimization bridge among LUCC, ST modelling, and big data.  相似文献   

Enabling point pattern analysis on spatial big data using cloud computing: optimizing and accelerating Ripley’s K function     

Guiming Zhang  Qunying Huang  John H. Keel 《International journal of geographical information science》2016,30(11):2230-2252

Performing point pattern analysis using Ripley’s K function on point events of large size is computationally intensive as it involves massive point-wise comparisons, time-consuming edge effect correction weights calculation, and a large number of simulations. This article presented two strategies to optimize the algorithm for point pattern analysis using Ripley’s K function and utilized cloud computing to further accelerate the optimized algorithm. The first optimization sorted the points on their x and y coordinates and thus narrowed the scope of searching for neighboring points down to a rectangular area around each point in estimating K function. Using the actual study area in computing edge effect correction weights is essential to estimate an unbiased K function, but is very computationally intensive if the study area is of complex shape. The second optimization reused the previously computed weights to avoid repeating expensive weights calculation. The optimized algorithm was then parallelized using Open Multi-Processing (OpenMP) and hybrid Message Passing Interface (MPI)/OpenMP on the cloud computing platform. Performance testing showed that the optimizations effectively accelerated point pattern analysis using K function by a factor of 8 using both the sequential version and the OpenMP-parallel version of the optimized algorithm. While the OpenMP-based parallelization achieved good scalability with respect to the number of CPU cores utilized and the problem size, the hybrid MPI/OpenMP-based parallelization significantly shortened the time for estimating K function and performing simulations by utilizing computing resources on multiple computing nodes. Computational challenge imposed by point pattern analysis tasks on point events of large size involving a large number of simulations can be addressed by utilizing elastic, distributed cloud resources.  相似文献   

Free and open source software for geospatial applications (FOSS4G) to support Future Earth     

Maria Antonia Brovelli  Marco Minghini  Rafael Moreno-Sanchez  Ricardo Oliveira 《International Journal of Digital Earth》2017,10(4):386-404

ABSTRACT

The development, integration, and distribution of the information and spatial data infrastructure (i.e. Digital Earth; DE) necessary to support the vision and goals of Future Earth (FE) will occur in a distributed fashion, in very diverse technological, institutional, socio-cultural, and economic contexts around the world. This complex context and ambitious goals require bringing to bear not only the best minds, but also the best science and technologies available. Free and Open Source Software for Geospatial Applications (FOSS4G) offers mature, capable and reliable software to contribute to the creation of this infrastructure. In this paper we point to a selected set of some of the most mature and reliable FOSS4G solutions that can be used to develop the functionality required as part of DE and FE. We provide examples of large-scale, sophisticated, mission-critical applications of each software to illustrate their power and capabilities in systems where they perform roles or functionality similar to the ones they could perform as part of DE and FE. We provide information and resources to assist the readers in carrying out their own assessments to select the best FOSS4G solutions for their particular contexts and system development needs.  相似文献   

Spatial Thinking Assists Geographic Thinking: Evidence from a Study Exploring the Effects of Geospatial Technology     

Sandra Metoyer  Robert Bednarz 《The Journal of geography》2017,116(1):20-33

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