交互式地图综合过程中的符号可视化问题

针对计算机地图综合仍然以人机交互的方式为主的现状,本文根据地图综合操作中的符号可视化的四个特点,提出了建立以单套比例尺符号库适宜多套比例尺地形图数据的可视化方案。通过定义不同比例尺之间符号的衰减系数,讨论了单套比例尺可视化多套比例尺数据的实现方式,并结合1:1万地形图缩编至1:5万地形图进行了模拟实验。     

Problems of mapping a nature reserve: Aberlady Bay LNR and SSSI

Abstract

A new five-colour map of Aberlady Bay Local Nature Reserve and Site of Special Scientific Interest at 1:7,500 scale is published as a loose insert with the June 1993 issue of The Cartographic Journal. This accompanying paper describes the problems of producing the map at minimal cost, considers some of the cartographic issues particular to the site, and provides specification details of the compilation.

Such individual map sheets, which are used for environmental planning, research and teaching, have in the past been produced mainly by universities with the support of conservancy and countryside agencies. Future production costs at universities will inevitably rise although some economies may be possible by the use of digital database methods of cartography.     

Why Maps Matter in GIScience

Abstract

This paper is an elaboration of the theses proposed in ‘Cartographic presentation of forms and degradation of the natural environment: sozological map on a scale of 1∶50?000’ (), where a sozological map of Poland was presented. The said map contained comprehensive cartographic information on the forms of environmental protection and degradation, made to a scale of 1∶50?000. The thematic scope of the map has already been modified twice: in 1997 and in 2005, with the ensuing changes presented in corresponding manuals: Sozological Map on a Scale of 1∶50?000, in an Analogue and Digital Form (Chief National Geodesist, 1997) and Technical Guidelines GIS-4. Sozological Map of Poland, Scale of 1∶50?000, in an Analogue and Digital Form (2005). Many years’ worth of experience gained since the launch of this cartographic system points out to the need for broadening the presented content and improving the map’s scale. Thus, attempts have been made at rescaling the map to 1∶10?000. Increasing the degree of detail is particularly necessary for presenting areas of intensive human activity. In this paper, the authors propose technical and graphical solutions for the 1∶10?000 scale.     

Maps for the Reluctant

Abstract

This paper describes the design and development of two trial 1:100 000 scale Ordnance Survey maps targeted specifically at the inexperienced and reluctant map users in the touring and holiday market. These are two maps which depart from the very high map specification designs normally offered by Ordnance Survey. The use of extensive consumer market research and the objective analysis of existing touring type maps on sale have enabled Ordnance Survey to publish two experimental maps, which will succeed or fail by consumer reaction alone.     

THE APPLICATION OF TRANSFORMATION FACTORS TO THE ADJUSTMENT OF AIR PHOTOGRAPHS COVERING NARROW LAND AREAS AND COASTLINES

Abstract

1. This new method of adjusting air photographs numerically to a uniform scale on a final map grid has already been described by the writert, where it concerns a large block-adjustment. The method to be described in this paper is the application of the same principle to the adjustment of photographic strips, covering narrow land areas and coastlines.     

'Be Map Aware: Cutting-edge…Not Close to the Edge'

Abstract

An assessment is made of the accuracy of the map and written survey, which is essentially a list of land-holders and the areas held by each, and of their mutual consistency. The geometry of the map is compared quantitatively with that of the first edition (1852) Ordnance Survey 6-inch (1 : 10 560) map. The Saxton map is found to have a scale of 1 : 5140, leading to the conclusion that the perch used in the scale bar represents 7¹/₉ yards or thereabouts. The areas quoted in the written survey are consistent with acres based on this value. The positional accuracy of points on the map is found to be ～20 m, and areas of typical plots determined from the map are uncertain by between about 4 and 12%. The relationship between these two facts can be understood through a detailed study of the statistics of the errors in separations of points on the map. The written survey is found to omit a substantial number of plots of land from its listings. The map thus appears to be more reliable overall than the written survey.     

Effects of Animations in Zooming and Panning Operations on Web maps: A Web-based Experiment

Abstract

The presentation of graphics and maps on the Internet has led to the development of several new techniques. The use of dynamics and animations in maps has increased, and new types of applications are emerging frequently. Recently, several map providers on the web have introduced zooming in maps as an animated operation. In this paper, we look closer into how the animated zoom is perceived by participants in an experiment, and compare these observations with a corresponding test where the map scale is changed in more abrupt steps. The results indicate significant preference for the animated zoom. The experiment itself is carried out through the World Wide Web and all the participants made their contribution from their own computers.     

Use of Artificial Neural Networks for Selective Omission in Updating Road Networks

Abstract

An important problem faced by national mapping agencies is frequent map updates. An ideal solution is only updating the large-scale map with other smaller scale maps undergoing automatic updates. This process may involve a series of operators, among which selective omission has received much attention. This study focuses on selective omission in a road network, and the use of an artificial neural network (i.e. a back propagation neural network, BPNN). The use of another type of artificial neural network (i.e. a self-organizing map, SOM) is investigated as a comparison. The use of both neural networks for selective omission is tested on a real-life road network. The use of a BPNN for practical application road updating is also tested. The results of selective omission are evaluated by overall accuracy. It is found that (1) the use of a BPNN can adaptively determine which and how many roads are to be retained at a specific scale, with an overall accuracy above 80%; (2) it may be hard to determine which and how many roads should be retained at a specific scale using an SOM. Therefore, the BPNN is more effective for selective omission in road updating.     

Approach to calculating spatial similarity degrees of the same river basin networks on multi-scale maps

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.     

BinSq: visualizing geographic dot density patterns with gridded maps

ABSTRACT

Dot maps have become a popular way to visualize discrete geographic data. Yet, beyond showing how the data are spatially distributed, dot maps are often visually cluttered in terms of consistency, overlap, and representativeness. Existing clutter reduction techniques like jittering, refinement, distortion, and aggregation also address this issue, but do so by arbitrarily displacing dots from their exact location, removing dots from the map, changing the spatial reference of the map, or reducing its level of detail, respectively. We present BinSq, a novel visualization technique to compare variations in dot density patterns without visual clutter. Based on a careful synthesis of existing clutter reduction techniques, BinSq reduces the wide variety of dot density variations on the map to a representative subset of density intervals that are more distinguishable. The subset is derived from a nested binning operation that introduces order and regularity to the map. Thereafter, a dot prioritization operation improves the representativeness of the map by equalizing visible data values to correspond with the actual data. In this paper, we describe the algorithmic implementation of BinSq, explore its parametric design space, and discuss its capabilities in comparison to six existing clutter reduction techniques for dot maps.     

Mapping for Cycle Touring in Britain; Past,Present, and a Possible Future

Abstract

The Lack hitherto of studies of cycle-touring mapping in Britain is noted, and some basic attributes of cycle touring, including speed, daily distance, gradients and wind, are described. Essential and desirable qualities for a cycle-touring map are enumerated, including the need to depict all rural routes available to cyclists; it is concluded that the optimum scale is in the range 1:100 000–1:126 720, and that relief should by contours at an interval not greater than 30 metres. National mapping in the optimum scale range which were published after 1945 are then reviewed, and reasons suggested as to why none has been kept in print. The mapping available for cycle touring in Britain in 2001 is Ordnance Survey (OS) 1:50 000 Landranger series contains all the necessary information, it is too bulky to be suitable; and that most of the other maps published in the optimum scale range have inadequate relief information and all offer very limited geographical cover. The potential competition for the OS 1:50 000 from a national map series in the optimum scale range is acknowledged, and an outline specification for a 1:125 000 series is described, which seeks to minimize that competiton whilst providing all the necessary information for cycle touring.     

Bartholomew and the Half-Inch Layer Coloured Map 1883–1903

Abstract

In their pre-war heyday Batholomew, that most famous of British commercial mapmakers, had a huge worldwide business in every sort and scale of map and atlas for every purpose; not to mention, at one time, an extensive general printing trade. But, even so, their name became firmly associated in the public consciousness with one particular design of map on one particular scale — the half-inch to one mile (1.126 720) layer colored map of Great Britain. This study deals with the early history of the phenomenon, in the context of the firm's other work. It concludes with the completion of the England and Wales series, and the moment when it could be said, in the most elevated and objective of contexts, that the British map buyer — trade and public both — had, thanks to this map, acquired 'the Bartholomew habit'.     

NOTES ON THE USE OF THE SLIDE-RULE IN TOPOGRAPHICAL SURVEYING

Abstract

The Survey in which the following methods were employed was for a final map on a scale of 1/500,000, with contours at a 500-foot Vertical Interval. In order to make use of any available information shown on existing maps, the scale used in different areas in the field was that of existing maps. These scales were 1,000 roods to 1 inch (1 rood = 12.396 English feet), 840 roods to 1 inch (1/125,000), and 1,680 roods to 1 inch (1/250,000).     

Experiments in the Design of 1:100 000 Scale Topographic Mapping for Great Britain

Abstract

Most European countries have a national topographic map series at 1:100 000 scale, but currently Great Britain does not. The history of mapping at or around 1:100 000 in Britain is described briefly and consideration given as to why such a scale would be appropriate for a national series of mapping aimed at tourist and leisure users. The main focus of the article is to review a series of 1:100 000 scale maps of two sample areas of Great Britain, produced in the style of various western European medium scale topographic maps. Two further design examples are produced combining desirable characteristics of the maps examined. The results show both that many of the designs translate well to 1:100 000 scale maps of the British landscape and that there is considerable potential for a topographic base at this scale providing a basis for a national series aimed at tourist and leisure users.     

Determining a Vertical Scale for Graphical Representations of Three-Dimensional Surfaces

Abstract

The selection of a vertical scale in the production of block diagrams or three-dimensional views is a decision which can have a great effect on the map reader's perception of the information presented. Advice available in the cartographic literature is extremely subjective and refers mainly to physical data. In the absence of suitable guidelines for statistical mapping, an experimental technique is presented which utilises the power of automated cartography in determining a scale which can be applied to all types of three-dimensional surfaces.     

Weight-Setting and Quality Assessment in Simultaneous Graphic Generalization

Abstract

Cartographic generalization aims at simplifying the representation of data to suit the scale and purpose of the map. This paper deals with a method that implements the whole graphic generalization process (roughly defined as the operators simplification, smoothing, exaggeration and displacement) called simultaneous graphic generalization. This method is based on constraints, i.e. requirements that should be fulfilled in the generalization process. The constraints strive to make the map readable while preserving the characteristics of the data, which implies that all constraints cannot be completely satisfied. This study was concentrated on finding the optimal compromise between the constraints in simultaneous graphic generalization by setting weights for the constraints. Four strategies for determining the weights are described and their advantages and disadvantages are discussed. The discussion is based on the following assumptions: the constraints are independent, and the weights are only dependent on constraint type and object type. A comparison of the strategies reveals that the strategy constraint violation is the most promising. One advantage with this strategy is that it is related to the quality requirements of the map, and another advantage is that it provides a numerical measure for quality assessment. The paper concludes with a case study of the constraint violation strategy, in which visualization of the numerical quality measure is used. The case study shows that the constraint violation strategy gives a sound compromise between the constraints.     

区县级地名图集中符号的视觉层次设计——以《汕头市澄海区地名图集》为例

第二次全国地名普查（以下简称“二普”）数据具有精度高、类型全面、现势性强等特点。如何对地名数据进行最优符号化是“二普”成果转化中一个重要的问题。为此,本文构建了地图符号库树结构模型,提出从主题尺度、符号形态、要素分类分级3个方面进行符号视觉层次构建的思路,充分利用视觉变量构图元素的组合实现多层次符号视觉效果。将该方法运用于《汕头市澄海区地名图集》的编制中,通过符号设计实例充分论证符号视觉层次体系设计在地名图集设计中的重要作用,可为“二普”成果转化工作中的地名图编制提供参考。     

Moving On. Where Should the University Map Collection be Going?

Abstract

This paper argues for the importance of retaining a map library presence on UK university campuses at a time when many are under threat of closure, and access to geospatial data is increasingly moving to web-based services. It is suggested that the need for local expertise is undiminished and map curators need to redefine themselves as geoinformation specialists, preserving their paper map collections, but also meeting some of the challenges of GIS, and contributing to national developments in the construction of distributed geolibraries and the provision of metadata, especially with regard to local data sets.     

基于GML的地图符号化研究与实现

采用基于GML（Geography Markup Language）地理标识语言,将地理要素符号化并表达出来。GML基于XML的架构,XML被设计为传输和存储数据,结构简单。使用基于GML的地图制图,就是一种基于规则的产生式方法,具有模块性和清晰性结构,这种结构易于地图要素的符号化管理和扩展,全方位地表达地图信息。     

New measures for analysis and comparison of shape distortion in world map projections

ABSTRACT

World maps can have quite different depictions of reality depending on the projection adopted, and this can influence our perception of the world. In this respect, shape is a significant property that needs to be considered, especially when representing large regions in general-purpose world maps. A map projection distorts most geometric properties (area, distance, direction/angle, shape, and specific curves) and usually preserves a single property or provides a compromise between different properties when transforming terrestrial features from globe to plane. The distortions are mainly classified based on area, distance and direction/angle and analyzed with Tissot’s theorem. However, this theorem offers a local (pointwise) solution, so the distortion assessment is valid at infinitesimal scale (i.e. for very small regions). For this reason, different approaches are required to analyze the distortions at finite scale (i.e. for larger regions). However, there are very few attempts at analyzing and comparing shape distortion of landmasses in world map projections owing to the fact that shape measurement is difficult and usually involves measuring different characteristics. Seeking to fill this gap, in this study, compactness and elongation distortion measures are introduced. In this regard, 16 world map projections are analyzed and compared with these distortion measures in a GIS environment, based on map datasets of continents and countries. An analysis of the effect of the levels of detail of the datasets is also presented.