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1.
Successful implementation of an intelligent system for automated map generalization requires formalization of cartographic principles that are, in many cases, only intuitively understood. Formalizing these principles requires acquisition and re-expression in the form of semantic nets, frames, production rules, or similar formalization methods. The various techniques for cartographic knowledge acquisition have been discussed on a theoretical basis; however, little empirical research has been conducted. This paper reports on empirical acquisition of cartographic knowledge by reverse engineering; that is, on trying to recapitulate decisions made on published documents or maps. The work is based on a computer-assisted multi-scale inventory of the Austrian National Topographic Map Series. Queries of the relational database, within which inventory data are stored, lead to the formulation of prototype production rules for modifying map symbols during automatic scale changes. Components of map generalization expressed in such rules include the selection behavior of settlement, transportation, and hydrographic objects, and the degree of simplification of settlement domains and building clusters. The acquired cartographic knowledge reveals quantitative relations between map elements and the changes in these relations that occur with scale transition. These insights can guide subsequent knowledge refinement using other acquisition methods. This paper provides, in addition, a conceptual framework by which other topographic map series may be compared at multiple scales.  相似文献   

2.
Map reading is effective to the extent that the user has a basic understanding of the nature of geographical information, is familiar with the logic of various cartographic techniques, and grasps the map deciphering problems that may result through the matching of cartographic method to geographical data in specific mapping situations. The qualitative/quantitative dichotomy that was formerly so frequently resorted to when dealing with geographical information has been replaced by a more sensitive four-level measurement scheme or scaling system which is not only useful in sorting out the relations between environmental information and its cartographic portrayal, but which also provides an important key to understanding the special interpretative considerations that these relations create for the map reader. From a measurement perspective, the information yielded by a particular map symbol depends on the nature of the data that go into its construction, the nature of the data that survive the symbolic transformation, and the ability of the map user to decode the symbol effectively. The utility of measurement concepts in map reading is further demonstrated in the clarifying effect they can have in determining map information content and in the area of map generalization.  相似文献   

3.
Spatial decision-making in time-critical situations requires effective and usable two-dimensional and three-dimensional (3D) cartographic products. Holographic displays allow decision makers to work with auto-stereoscopic maps without the hassle of interacting with complex user interfaces or additional vision hardware. Holographic production processes have advanced greatly in a short period and now support timely and full integration of digital 3D models in geospatial holograms. George Mason University’s and Zebra Imaging’s research on interactive holographic motion displays showcases the leadership in moving cartography and geovisualization research in the US forward. In close cooperation with academic researchers, decision makers, and domain experts, the usability and usefulness of these cartographic products is tested and design guidelines for effective geospatial holograms are being developed.  相似文献   

4.
In economy, society and personal life map-based interactive geospatial visualization becomes a natural element of a growing number of applications and systems. The visualization of 3D geospatial information, however, raises the question how to represent the information in an effective way. Considerable research has been done in technology-driven directions in the fields of cartography and computer graphics (e.g., design principles, visualization techniques). Here, non-photorealistic rendering (NPR) represents a promising visualization category – situated between both fields – that offers a large number of degrees for the cartography-oriented visual design of complex 2D and 3D geospatial information for a given application context. Still today, however, specifications and techniques for mapping cartographic design principles to the state-of-the-art rendering pipeline of 3D computer graphics remain to be explored. This paper revisits cartographic design principles for 3D geospatial visualization and introduces an extended 3D semiotic model that complies with the general, interactive visualization pipeline. Based on this model, we propose NPR techniques to interactively synthesize cartographic renditions of basic feature types, such as terrain, water, and buildings. In particular, it includes a novel iconification concept to seamlessly interpolate between photorealistic and cartographic representations of 3D landmarks. Our work concludes with a discussion of open challenges in this field of research, including topics, such as user interaction and evaluation.  相似文献   

5.
One of the most fundamental steps in map creation is the transformation of information from the surface of a globe onto a flat map. Mapmakers have developed and used hundreds of different map projections over the past 2,000 years, yet there is no perfect choice because every map projection uniquely alters some aspect of space during the transformation process. Detailed information about the type, amount, and distribution of distortion is essential for choosing the best projection for a particular map or data set. The distortion inherent in projections can be measured and symbolized much like any other map variable. Methods for symbolizing map projection distortion are reviewed, with each method described and illustrated in graphical form. The symbolization methods are collected under ten separate headings organized from simple to more complex in terms of interpretation. Most of these methods are highly effective at communicating distortion, yet they are rarely used beyond textbooks and technical documentation. Map projections and the distortions they carry need to be better understood by spatial data developers, distributors, and users. Map distortion should be carried along with map data as confidence layers, and the easily accessible distortion displays should be available to help in the selection of map projections. There is a suitably wide array of symbolization methods to match any need from basic education to research.  相似文献   

6.
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   

7.
Animation is an important method of communicating information that lends itself to cartographic display. Cartographers may be delinquent in their utilization of this technique. Meteorologists, medical researchers, and physical scientists, employing mini-, mainframe, and supercomputers, are creating today's most sophisticated animated maps and continue to develop high-quality systems for data display. Though today's cartographers are concerned with the geometric accuracy and computer automation of their map products, they may be overlooking current developments in spatiotemporal display within other disciplines. Creating a method to bridge the current animation gap between cartography and these disciplines has been the primary goal of this research. Since personal computers are the platforms most commonly available to cartographers, development of animated cartographic displays is feasible with this technology. As a result of this research, an interactive microcomputer-based animated map of U.S. surface temperatures was designed to help understand the rapid climatic change occurring during the 20th century.  相似文献   

8.
9.
Cartographers must make numerous decisions during the process of constructing a map. In the present era, when spatial data sets are abundant and mapping software is accessible to the general public, cartographic knowledge developed in the literature is under-used and threatened with irrelevance. We view cartographic design as a multiobjective problem solving process that must meet many, often conflicting, goals. The application of this multiobjective view to cartographic design will help a new generation of cartographers develop design capabilities. We illustrate our concepts using several thematic mapping examples.  相似文献   

10.
The geospatial field significantly influences the development of the environmental domain, including a wide range of geospatial and cartographic information systems, such as Geographic Information Systems (GIS), Multimedia Atlas Information Systems (MAIS) and more recently web-based GIS (Web-GIS). In this context, we introduce web-based environmental geospatial information systems (Web-EGIS) as a special case of Web-GIS, aiming to integrate the functionalities of geospatial information systems with the enormous quantity of specialized, distributed and highly heterogeneous environmental geo-referenced data and services. We define three main characteristics of the Web-EGIS. The first is a generic hypercube-based data organization and visualization. The next characteristic is a standard-based, three-tier service-oriented architecture. The third and last characteristic is the traceability of the architectural and design decisions, for which we introduce the new concept of an ‘Environmental Application Context’, arguing that not only the functional but also the non-functional requirements (NFRs) have an important role in defining the architecture, software components and data services of such systems. In a nutshell, a Web-EGIS is characterized by a coherent user experience through the hypercube-based visualization concept, technically supported by a service-oriented architecture that is structured according to an extensive analysis of NFRs. On this basis, we introduce the Geodata visualization and interactive training environment (GeoVITe) Platform for Interdisciplinary Environmental Research as a reference implementation of a Web-EGIS with its basic design requirements, integrative hypercube-based visualization for heterogeneous data sources, extended web cartography functionalities, and its de facto system architecture. The concept of the hypercube-based visualization is better transferred to the system architecture by understanding the ‘Environmental Application Context’ of this particular Web-EGIS, which also makes it easier to maintain and enhance. The resulting system is a support platform for research activities in the environmental domain.  相似文献   

11.
自适应地图可视化系统设计研究   总被引:10,自引:0,他引:10  
传统的地图可视化系统设计思想已经不能完全适应现阶段地图可视化系统发展的需要,如何满足不同用户的个性化需求,是地图可视化系统进一步发展所面临的重要问题。自适应地图可视化系统,将自适应理论引入到地图可视化系统的设计开发中,为解决这一问题提供了一种有效的方法。文中阐述了自适应地图可视化系统的概念和提出背景,分析了建立自适应地图可视化系统所需要研究的内容,并以自适应用户界面为重点探讨了设计自适应地图可视化系统的基本原理和方法。  相似文献   

12.
基于地图的地理信息可视化现状与发展   总被引:10,自引:0,他引:10  
地理信息可视化是在地理数据库驱动下,以地图形式表达地理信息的过程。地图可视化和GIS可视化是地学可视化研究的两个重要部分,地图可视化通常在制图系统中完成,脱离了地理数据库,不便于地图更新;GIS可视化又缺乏足够的地图制图工具。文中探讨了地理数据库驱动下的地图表达机制,融入了地图制图机制与GIS符号化,形成GIS数据管理、数据综合、符号化、图形综合一体化的地图表达模型。  相似文献   

13.
14.
Communication of natural hazard assessment results is crucial to protect people and infrastructure from devastating impacts of extreme events. While hazard maps provide important information on potential impacts, their interpretation and the general knowledge exchange between stakeholders is often difficult. Web-based information systems contain the potential to support hazard management tasks by fast distribution and customization of hazard visualizations through interactive functionality. Cartographic principles are, however, often ignored in existing web-based visualizations which leads to poor graphical results and consequently to an impairment of the information flow. While these issues need to be solved, a new task is already waiting: the integration of uncertainty information into hazard visualizations. Since many hazard management activities rely on hazard assessment results, communication of associated uncertainties among experts is vital.

The challenge of this research is to overcome these existing shortcomings by combining high quality cartographic visualizations of natural hazard data as well as associated uncertainties with interactive functionality. The resulting web-based cartographic information system will convene the needs of natural hazard specialists by offering a high level of customization: the suggested visualizations include various cartographic techniques such as the application of textures, bars, and interpolated surfaces. The possibility to interactively select particular data sets, customize colors, choose dimensions, query attribute data, and include uncertainty information facilitates the interpretation of complex data and finally the communication among natural hazard specialists.

In this article we summarize requirements that have to be considered, suggest functionalities necessary to perform natural hazards management tasks, and present a prototype of an expert system for the visualization and exploration of natural hazards assessments results and associated uncertainties.  相似文献   

15.
地图可视化系统用户界面是实现用户和地图可视化系统交互的关键环节,但对这一情况目前地图学界还没有给予足够的重视。本文首先拓宽用户界面的概念并介绍了地图可视化系统用户界面元素,通过分析现有地图可视化系统用户界面设计中存在的一些问题,提出了基于认知规律的地图可视化系统用户界面设计原则,并通过实例进行了详细说明。  相似文献   

16.
In recent years, the visualization of geospatial data has undergone dramatic and important developments. Next to static maps, nowadays, immersive and highly interactive virtual environments can be used to explore and present dynamic geospatial data. Additionally, the World Wide Web has developed into a prominent medium to disseminate geospatial data and maps. In visualizing geospatial data, methods and techniques from fields, such as scientific visualization and information visualization, are applied because of the large volumes of data at hand. This has accumulated in what is known as geovisualization—the use of visual geospatial displays to explore data and through that exploration to generate hypotheses, develop problem solutions and construct knowledge. Maps and other linked graphics play a key role in this process. The objective of this paper is to demonstrate the usefulness of geovisualization and, in particular, how alternative graphic representations can stimulate the visual thought process. This is demonstrated by applying geovisualization techniques to Minard's well-known map of Napoleon's 1812 campaign into Russia, the “Carte figurative des pertes successives en hommes de l'Armee Française dans la campagne de Russie 1812–1813” (http://www.itc.nl/personal/kraak/1812/).  相似文献   

17.
自适应地图可视化系统中用户模型构建与匹配算法研究   总被引:1,自引:0,他引:1  
谢超  陈毓芬  吴增红 《测绘学报》2011,40(1):118-124
为增强自适应地图可视化系统中用户模型构建和匹配的准确性,提出四元组交互用户模型及基于概率的相似度匹配算法.该模型充分考虑了自适应地图可视化系统中的"人""机"交互特征,能更加全面反映用户在使用自适应地图可视化系统时的特征.详细地介绍概率的相似度匹配算法的基本思想和实现过程.最后进行实例验证.实例证明,所提出的用户模型构...  相似文献   

18.
From the application of information theory capacity limits of maps are derived and some cartographic rules are formulated—based on theoretical models and perception studies. The perception study shows that for a relief map with coloured height intervals the channel capacity, as defined in information theory, is reached at seven~eight height classes. Generally, the length of a visual variable may be characterized by the channel capacity of the map. This theoretical study shows how increased attention should be paid to perceptual separation as the number of categories increases. The requirement becomes more and more crucial as the number of categories exceeds five. The principle of group visibility is formulated and demonstrated. Group visibility considers the visibility of groups of map features and may be utilized in a visual search for geographical patterns. The quantitative measures presented offers computational methods to control group visibility for example in an interactive visualization system.  相似文献   

19.
图标是地图可视化系统一个重要组成部分,图标设计是实现用户和地图可视化系统交互的关键环节,但对这一情况目前地图学界还没有给予足够的重视。文中阐述了图标在普通软件中的应用、作用以及用户如何去认知图标,并对地图可视化系统中图标设计常见的问题进行了分析,提出了地图可视化系统中图标设计的一般原则,并给出了图标设计实现的一个实例。  相似文献   

20.
基于用户认知特征的地图可视化系统自适应用户界面研究   总被引:24,自引:0,他引:24  
凌云  陈毓芬  王英杰 《测绘学报》2005,34(3):277-282
地图可视化系统用户界面是地图可视化系统和用户进行信息交互的接口.用户界面存在的问题制约用户对地图可视化系统应有功能的使用.以地图可视化系统的用户为中心,通过探讨用户的认知特征和分析现有地图可视化系统用户界面设计中存在的一些问题,拓宽用户界面的概念,设计一种地图可视化系统自适应用户界面的初步机制,探索让系统的用户界面自动地适应用户特征的方法.  相似文献   

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