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1.
廖克 《测绘学报》2017,46(10):1517-1525
本文分3部分:第1部分是中国古代和近代地图学发展历史的简要回顾,阐明中国是世界上地图出现最早的国家之一,在世界地图学发展史上占有重要地位,对世界地图学的发展作出过重要贡献,直至15世纪的中国明代,中国地图和地图学始终领先于西方国家,只是清代以后,才落后于西方发达国家;第2部分阐述新中国成立后中国地图事业和地图学飞速发展,在全国地形图的测绘与编制、专题地图与地图集编制、遥感制图、计算机制图、多媒体电子地图、移动通信地图、互联网地图、地图学理论研究等方面取得了巨大成就,赶上了世界先进水平;第3部分提出新世纪中国地图与地图学方向与任务的调整,分析了大数据、互联网和人工智能时代地图学的机遇、挑战与展望。大数据通过三维动态地图可视化,能够显示事物和现象的空间格局与区域分异及时空动态变化,进而作出分析评价、预测预报、区划布局、规划设计、管理调控。因此地图学在大数据时代能够发挥重要作用。今后互联网将成为地图编制与应用的主要平台,地图会更加大众化、个性化、智能化与实用化。  相似文献   

2.
As mapping is costly and labor‐intensive work, government mapping agencies are less and less willing to absorb these costs. In order to reduce the updating cycle and cost, researchers have started to use user generated content (UGC) for updating road maps; however, the existing methods either rely heavily on manual labor or cannot extract enough information for road maps. In view of the above problems, this article proposes a UGC‐based automatic road map inference method. In this method, data mining techniques and natural language processing tools are applied to trajectory data and geotagged data in social media to extract not only spatial information – the location of the road network – but also attribute information – road class and road name – in an effort to create a complete road map. A case study using floating car data, collected by the National Commercial Vehicle Monitoring Platform of China, and geotagged text data from Flickr and Google Maps/Earth, validates the effectiveness of this method in inferring road maps.  相似文献   

3.
Spurious evidence and spurious spatial associations between target mineral deposits and certain classes of spatial data undermine GIS-based data-driven modeling of mineral prospectivity. In a case study application of data-driven evidential belief functions, such problems were recognized and then, based on sound geological judgment, were addressed accordingly. By invoking knowledge of genetic associations between mineral deposits of the type sought and spatial geological attributes (lithology, fault/fracture density, hydrothermal alteration intensity), spurious spatial associations depicted in ‘original’ evidence maps were addressed by treatment of input spatial data via applications of certain basic GIS functionalities in order to derive ‘treated’ evidence maps. By invoking knowledge of geological processes involved in the formation of mineral deposits of the type sought and knowledge of how operations to combine evidence maps function, the integration of evidence maps was guided such that the inter-play of geological processes involved in the formation of mineral deposits of the type sought is represented in the modeling procedure and such that spurious evidence is filtered and not transmitted into the output map representing likelihood of mineral deposit occurrence in every location within a study area. The results show that: (a) using ‘treated’ evidence maps, instead of ‘original’ evidence maps, results in better mineral prospectivity maps and, thus, (b) knowledge-guided data-driven modeling of mineral prospectivity is better than a ‘purely’ data-driven modeling of mineral prospectivity.  相似文献   

4.
Information‐rich maps are today rendered from powerful back‐end servers. Unfortunately, there may be circumstances in which access to such Internet‐resident web services is infeasible or unreliable. These disconnected environments can theoretically occur during major power outages, malicious attacks on communications infrastructure, natural disasters, or in remote operating environments. One might also envision applications in which a disconnected service is preferred over Internet‐resident services, such as when the local internet service is overloaded with traffic, making communication though it difficult. To this end, this article presents a software stack (a map stack) that can serve GIS information from low power embedded nodes. The system combines a spatially enabled SQL database, location‐based routing, and multi‐scale map rendering to serve information‐rich GIS data on common hand‐held devices at minimal energy consumption. The maps are rendered on browsers on off‐the‐shelf mobile devices such as smart phones and tablets. The system also provides a crowd sourced capability where end users can annotate maps with up‐to‐date information on the scene of the natural disaster. We have prototyped a fully functional map stack on a battery powered Gumstix Overo air platform. We show that the map stack is a highly extensible platform that provides low latency, and low energy dissemination of maps during a natural disaster.  相似文献   

5.
The quality of spatial data is limited by the accuracy of their sources such as paper maps and satellite images. It is also reduced by errors in map digitization and photo interpretation. Spatial operations performed on spatial data such as map overlay, buffer operations and spatial smoothing, do not always work correctly because their accuracy depends on the quality of spatial data. The present paper evaluates the accuracy of the buffer operation on a point and a line segment in relation to the positional accuracy of spatial data. Two quantitative measures are introduced to assess the accuracy of the buffer operation. Their explicit forms are derived for a point, and a condition is presented where the measures can be evaluated efficiently by numerical calculation. Applications provide empirical findings that deepen our understanding of the relationship between the accuracy of spatial data and that of the buffer operation.  相似文献   

6.
This paper presents concepts that motivate the use of hexagon mosaic maps and hexagon-based ray-glyph maps. The phrase "hexagon mosaic map" refers to maps that use hexagons to tessellate major areas of a map, such as land masses. Hexagon mosaic maps are similar to color-contour (isarithm) maps and show broad regional patterns. The ray glyph, an oriented line segment with a dot at the base, provides a convenient symbol for representing information within a hexagon cell. Ray angle encodes the local estimate for the hexagon. A simple extension adds upper- and lower-confidence bounds as a shaded arc bounded by two rays. Another extension, the bivariate ray glyph, provides a continuous representation for showing the local correlation of two variables. The theme of integrating statistical analysis and cartographic methods appears throughout this paper. Example maps show statistical summaries of acidic deposition data for the eastern United States. These maps provide useful templates for a wide range of statistical summarization and exploration tasks. Correspondingly, the concepts in this paper address the incorporation of statistical information, visual appeal, representational accuracy, and map interpretation.  相似文献   

7.
With the declaration of India’s new map policy (NMP), user community is looking towards its impact on spatial accuracy of GIS theme maps arising out of transformation from existing system (Polyconic Projection on Everest 1830 spheroid datum) to Open series maps (OSM in UTM projection on WGS 84 ellipsoid) and vice versa. This results in registration error of existing maps with new maps. This study aims at finding out the impact of transformation on the spatial location and to determine the extent to which the existing theme layers can be used along with the new series maps without losing accuracy. Results show that there are some geographic regions in India whose GIS database can be used as it is available, depending on the scale and within the acceptable positional accuracy. For other region, depending on the scale of theme layers, a detail analysis of the situation will be required depending on project requirements.  相似文献   

8.
SVG具有适合网络发布的优点,其应用于地图网络传输与发布,既能解决目前地图网络发布面临的难点问题,又能增强基于网络的地图应用功能。分析了SVG应用于地图网络发布的优势,论述了地图符号的SVG描述与引用、地图数据的SVG编码与组织、SVG地图的显示控制与网络交互等关键技术,并提出了基于SVG的地图网络发布系统模型。  相似文献   

9.
随着互联网信息技术的飞速发展,电子化地图得到了广泛应用,高德地图、百度地图等互联网地图广泛应用于我们日常生活中,地图的美观性和设计感就决定了人们对它的第一印象。专题图作为一种集设计理念、空间信息于一体的地图产品,在很多场合中发挥着越来越大的作用。在制作专题地图中常常使用到的软件工具有ArcMap、CorelDRAW、Adobe Illustrator等,本文基于ArcMap进行专题图地图符号的设计,利用ArcMap专业地理信息的特性和强大的符号管理工具,对地图符号设计进行深入研究探索,发掘ArcMap对专题地图符号设计的潜力。  相似文献   

10.
在分析三维地形图特征的基础上全面探讨了三维地形图自动绘制时所面临的问题,从三维地形图数据组织、数据处理、空间关系处理、三维地图符号化等方面进行了研究,设计并实现了基于ArcEngine的三维地形图制图系统,利用西部的多幅地形图进行了实验,证明该软件是可行的。  相似文献   

11.
Advances in computer technologies have improved the quality of maps, making map comparison and analysis easier, but uncertainty and error still exist in GIS when overlaying geographic data with multiple or unknown confidence levels. The goals of this research are to review current geospatial uncertainty literature, present the Error‐Band Geometry Model (EBGM) for classifying the size and shape of spatial confidence intervals for vector GIS data, and to analyze the interpretability of the model by looking at how people use metadata to classify the uncertainty of geographic objects. The results from this research are positive and provide important insight into how people interpret maps and geographic data. They suggest that uncertainty is more easily interpreted for well defined point data and GPS data. When data is poorly defined, people are unable to determine an approach to model uncertainty and generate error‐bands. There is potential for using the EBGM to aid in the development of a GIS tool that can help individuals parameterize and model spatial confidence intervals, but more research is needed to refine the process by which people use the decision tree. A series of guiding questions or an “uncertainty wizard” tool that helps one select an uncertainty modeling approach might improve the way people apply this model to real‐world applications.  相似文献   

12.
数字地图的理论、方法和技术体系探讨   总被引:8,自引:4,他引:4  
本文探讨数字地图的理论、方法和技术体系,既介绍研究心得,更意在诚邀专家学者的合作。在理论体系方面,本文章阐述了数字地图的概念、体系结构、理论基础,以及数字地图带来的地图学新观念。在方法体系方面,文章阐述了数字地图能够解决的地学问题、数字地图的分析方法、数字地图的数据模型;在技术体系方面,文章阐述了数字地图制图系统、移动数字地图技术等内容。文章给出了数字地图的应用实例,包括国家自然地图集数据库、电子版、网络版,以及中国科学院资源环境数据库电子地图集等两内容。  相似文献   

13.
郭庆胜  李国贤  王勇  刘纪平  魏智威 《测绘学报》1957,49(10):1354-1364
地图综合中,建筑物群的排列结构是需要重点考虑的因素。当不同排列的子建筑物群之间存在空间图形冲突时,这些建筑物群的综合就显得更为复杂。直线排列建筑物群的综合在大比例尺地形图上以典型化操作为主。本文提出一种相互之间存在潜在空间图形冲突的多个直线排列建筑物子群的渐进式典型化方法,渐进式地处理多个直线排列建筑物子群之间的空间图形冲突,保留建筑物群重要的直线排列结构;以建筑物表达的视觉图形约束为限制条件,自动确定典型化后的建筑物位置、形状、大小和方位。本文还研究了基于建筑物群空间邻近图的直线排列建筑物子群的自动识别方法,分析了这些直线排列之间的邻近关系和相交关系。最后,以1:5000地图上的建筑物群综合为1:25 000为试验对象,验证了所提出算法的可用性和有效性。  相似文献   

14.
为解决我国数字化测图生产中数字地图的相邻图幅自动接边的难题,本文提出了一种可适用于微机的数字地图的接边方法——要素分类接边法。该方法分三步完成接边:(1)提取接边要素对;(2)接边要素对自动分类接边;(3)分幅剪辑与拼接。生产试验说明,这种接边方法可适用于各种大小比例尺的数字地图接边,可达到较高的自动化程度,接边效果满意。  相似文献   

15.
Abstract

Although the efficiency of label placement algorithms has been studied extensively, few studies considered the influence of the label designs on the efficiency of map readers. Labels are one of the most important elements on the map as they can provide more information than other symbols can. The design of the labels does have to stress the theme, shape and functionality of the associated objects, which results in a more efficient interpretation of the map content by the user. How the label designs can enhance the map readers’ efficiency (and thus the quality of the maps themselves) is the main objective of this study. A user study was conducted in which the participants were asked to locate a target label on a map. Different label designs were implemented across the trials. The participants’ reactions times were registered to measure their efficiency and statistically analysed using a one-way ANOVA. Two different users’ characteristics were considered: gender and expertise. Related to the size, shape, orientation and texture of the labels, a number of significant differences (P<0·05) and trends were located. Differences in efficiency between males and females, on the one hand, and between novices and experts, on the other hand, were also described statistically. Consequently, recommendations can be formulated regarding the design of labels in order to obtain more efficient maps, keeping in mind the map users’ characteristics.  相似文献   

16.
Computer-generated maps have become commonplace over the past decade. Most internet search engines, for example, have the ability to generate maps in response to spatial queries and routes between specified origins and destinations. Advances in mobile computing technologies provide access to these mapping capabilities from virtually any location on the Earth's surface. Maps and map-making have become ubiquitous, and this phenomenon requires cartographers to rethink basic concepts about map design and map use. In this special issue we present five research projects that are focused on the emerging field of ubiquitous cartography. These projects were selected, in part, because they are representative of key research challenges that face the cartographic research community. In this introductory paper, key terms are defined and research challenges outlined. By way of this collected set of papers, ubiquitous cartography is presented as a new and important arena for cartographic research.  相似文献   

17.
在现代到后现代社会的转变过程中, 人类的信息传播模式进入自媒体时代, 在地图上表现为制图用户向大众或地图爱好者转移, 地图的精确性不高、表达方式多样化。微地图是其中的一种, 旨在改善传统地图表达和大众地理空间认知的矛盾, 改进自媒体时代地图用户的主观信息表达, 突破传统地图仅从有限、规范化的角度和维度对地理事物和现象进行表达的局限。首先, 针对微地图的3个特点, 在后现代哲学的视角下分析其产生的原因并给予解释; 然后, 利用认知语言学的体验人本观、原型范畴论和去中心论等后现代哲学方法论, 对传统地图的空间认知、信息分类、制图表达等基础问题进行批判性分析和重构, 形成具有后现代哲学特点的微地图概念框架;最后, 通过实验验证了微地图存在的可能性及其后现代属性。  相似文献   

18.
蔡先华  王浪  付晓 《测绘通报》2020,(5):130-133
城市交通网络规模的不断扩大使得交通线路图成为一种常用地图。为了提高信息的传输效率,更好地保证图形的清晰易读性,出现了变形交通线路地图[1]。本文分析了变形交通线路图特性并对其自动制作过程进行了总结。为解决制作过程中地图符号冲突问题,提出了作用力驱动站点位移的交通线路图变形压缩方法。建立交通线路图中站点受力移动模型并设计了以坐标轴为轴心的移位算法。试验表明,该算法能够有效解决地图符号冲突问题,为完全自动制作变形交通线路图建立了基础。  相似文献   

19.
Obtaining spatial similarity degrees among the same objects on multi-scale maps is of importance in map generalization. This paper firstly defines the concepts of ‘map scale change’ and ‘spatial similarity degree’; then it proposes a model for calculating the spatial similarity degree between a river basin network at one scale and its generalized version at another scale. After this, it validates the new model and gets 16 points in the model validation process. The x-coordinate and y-coordinate of each point are map scale change and spatial similarity degree, respectively. Last, a formula for calculating spatial similarity degree taking map scale change as the only variable is obtained by the curve fitting method. The formula along with the model can be used to automate the algorithms for simplifying river basin networks.  相似文献   

20.
从等值线图形获取DAT和GRD格式的数据文件   总被引:2,自引:0,他引:2  
王宜芳 《现代测绘》2004,27(2):45-46
在盆地模拟研究工作中,需要处理大量的地质数据和地质图件,一方面,随时需要把各种数据变为可视的图形;另一方面,还时常需要从图形中得到研究中所必需的数据,例如,由构造图得到研究区域的深度数据文件。本文介绍一种从等值线图形获取DAT格式和网格化GRD格式的数据文件的方法。  相似文献   

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