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以地图自动综合为目的,定义了空间目标的几种基本空间关系.总结了道路、水系、居民地等要素之间存在的典型空间关系,着重讨论了它们之间空间关系抽象的规则,为地图自动综合中有效保持空间关系的一致性提供必要的理论基础. 相似文献
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郭庆胜 《武汉大学学报(信息科学版)》1999,24(3):83
讨论了面状要素图形轮廓简化的一些规则以及面的空间知识获取方法,结合以直角方式转折的面状要素图形轮廓的特点,重点讨论了其图形渐进式简化方法。 相似文献
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Acquiring and formalizing cartographic knowledge still is a challenge, especially when the generalization process concerns small-scale maps. We concentrate on the settlement selection process for small-scale maps, with the aim of rendering it more holistic, and making methodological contributions in four areas. First, we show how written specifications and rules can be validated against the actual published map products, thus pointing to gaps and potential improvements. Second, we use data enrichment based on supplementing information extracted from point-of-interest data in order to assign functional importance to particular settlements. Third, we use machine learning (ML) algorithms to infer additional rules from existing maps, thus making explicit the deep knowledge of cartographers and allowing to extend the cartographic rule set. And fourth, we show how the results of ML can be transformed into human-readable form for potential use in the guidelines of national mapping agencies. We use the case of settlement selection in the small-scale maps published by the Polish national mapping agency (GUGiK). However, we believe that the methods and findings of this paper can be adapted to other environments with minor modifications. 相似文献
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在地图制图综合中必须保持不同尺度同一区域地图要素之间拓扑关系的一致性,但目前有关的一致性评价方面的研究较少,本文讨论了不同比例尺地图中居民地与道路之间拓扑关系一致性的模糊评价问题。从制图规则和视觉限制的角度,分析了多尺度地图表达中居民地与道路之间的应该保持拓扑关系的一致性的几项规则;基于模糊数学理论提出了制图综合中拓扑关系的一致性评价模型,并通过一个简单实例证明了该方法的可行性。 相似文献
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示意性地图作为一种特殊的专题地图,较之传统专题地图,有着不同的制图法则和制图方法,目前,示意性地图的设计还缺乏充足的理论依据和技术支持,本文从图面、风格、符号等方面对示意性地图的设计进行了研究,提出了一些示意性地图综合的方法,最后将这些方法应用到一个实例之中。 相似文献
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本文论述了在地图数据库的基础上如何进行地形图智能综合系统的设计。地形图的自动综合是一个困难的大课题,本文只是就全要素的大比例尺地形图作了较详细的研究,同时提出了有关其它方面的策略。 相似文献
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《制图学和地理信息科学》2013,40(2):78-95
The automation of map design is a challenging task for both researchers and designers of spatial information systems. A main problem in automation is the quantification and formalization of the properties of the process to be automated. This article contributes to the formalization of some steps in the processes involved in map design and demonstrates how the Shannon information theory (Shannon and Weaver 1964) can be used to compute an evaluation index of a map, i.e., a parameter which measures the efficiency of the map. Throughout this article, the term "information" is mostly used in a narrow sense and the application of information theory is restricted to the syntactic level of cartographic communication. Information sources for map entropy computations are identified and elaborated on. A special class of map information sources are defined and termed "orthogonal map information sources". Further, a strategy to consider spatial properties of a map in entropy computations is presented. At the end of the article, some examples demonstrate how the channel capacity and other entropy related measures can be computed and used to control automated processes for map design or map generalization. 相似文献
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ABSTRACTOn nautical charts, undersea features are portrayed by sets of soundings (depth points) and isobaths (depth contours) from which map readers can interpret undersea features. Different techniques were developed for automatic sounding selection and isobath generalization. These methods are mainly used to generate a new chart from the bathymetric database or from a larger scale chart through selection and simplification. However, a part of the process consists in selecting and emphasizing undersea features formed by groups of soundings and isobaths on the chart according to their relevance to maritime navigation. Hence, automation of the process requires classification of features and their generalization through the application of a set of operators according not only to geometric constraints but also to their meaning.The objective of this work is to conceive a multi-agent system (MAS) for nautical chart generalization that is driven by the knowledge on the generalization process and the undersea features and their relationships. First, this work provides a feature-centered ontology modeling of the generalization process. Then, the MAS structure is introduced where agents access cartographic knowledge stored in the ontology. The MAS makes use of measure algorithms to evaluate constraint violations on the chart in order to decide which generalization operators to apply. The whole model has been implemented to provide generalization plans on a real case study. 相似文献
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结合生产实际,提出了1∶500-1∶2 000地形图缩编处理方法.在清华山维EPS 2008地理信息工作站上定制开发了1∶500-1∶2000地形图缩编平台,对现有1∶500 EDB数据源进行图元对照转换和制图综合完成复杂的地形图的编辑工作,其中制图综合采用全自动批处理、人机交互式,以及手工编辑相结合的处理模式. 相似文献
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《制图学和地理信息科学》2013,40(1):41-50
How to replace the human element of generalization with computer algorithms or rules in knowledge bases has been frequently discussed, but we have not succeeded in formulating these rules very well. The purpose of this article is to illustrate the problem of knowledge acquisition for generalization of topographic maps. Three studies to derive rule-based knowledge for automatic map generalization are presented and analyzed. In the tests, cartographers were asked to interpret map objects to be generalized and to describe the basis of their decisions. The studies showed that by interviewing cartographers, much of the domain knowledge can be gathered, but the most time-consuming part of documenting this knowledge is to analyze the data and formalize the results. It was also found that there is important domain knowledge on generalization that has not previously been documented. The tests performed resulted in the discovery of four categories of declarative rules: geometric, topological, context-related, and culture-related rules. 相似文献
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钟慧润 《测绘与空间地理信息》2017,40(5)
传统的地理底图缩编是在不小于本比例尺地形图的基础上通过拼接、内容取舍与更新、制图综合与编辑等地图制作技术,获取符合成图比例尺要求的地形图的过程[1],但实际生产中遇到的问题往往复杂得多,会有数据不是同一平台的情况,如何保质保量且快速高效地进行缩编,是一个比较有难度的技术问题。本文通过在实际生产中探索和实践,总结出一些技术要点,这些技术要点被证明是有效且实用的。 相似文献
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地图自动综合知识的分类及其形式化描述 总被引：1，自引：0，他引：1
在分析了已有地图综合知识的分类和表示方法的基础上 ,提出了一种新的地图综合知识的分类方法和形式化方法 ,这种分类方法易于系统开发 ,其形式化方法便于同地图综合模型和空间数据管理相结合。 相似文献
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郭庆胜 《武汉大学学报(信息科学版)》1999,(2)
从地图综合对象的本质特征出发,结合地图综合的自身规律,分解了地图自动综合问题。同时,在分析已有地图综合算子的基础上,提出了一套具有完备性的地图综合算子集合,讨论了算子的关联性和有序性。 相似文献
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以1∶2 000数字化地形图缩编1∶10 000地形图为例进行研究,通过对已有资料及现有技术标准的考察,依照制图综合的基本原理,总结出了1∶2 000地形图缩编的流程、基本方法。 相似文献