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1.
《制图学和地理信息科学》2013,40(2):155-157
In this article, we suggest that a universally accepted cartographic software program does not currently exist and has never existed, but mapping software capabilities are improving, and cartographers should be involved software developments for map making. We describe the current state of software development and explore what an ideal solution for the future would be. In a related vein, GIS and other data are not generally designed for cartography, but we are learning how they can be, and cartographers should also be involved in the modeling of GIS and other data used for map making. 相似文献
2.
《测量评论》2013,45(60):217-219
AbstractMap Projections.—A matter that should have been mentioned in the original article under this title (E.S.R., vii, 51, 190) is the definition of a map projection. In the list of carefully worded “Definitions of Terms used in Surveying and Mapping” prepared by the American Society of Photogrammetry (Photogrammetrie Engineering, vol. 8,1942, pp. 247–283), a map projection is defined as “a systematic drawing of lines on a plane surface to represent the parallels of latitude and the meridians of longitude of the earth or a section of the earth”, and most other published works in which a definition appears employ a somewhat similar wording. This, however, is an unnecessary limitation of the term. Many projections are (and all projections can be) plotted from rectangular grid co-ordinates, and meridians and parallels need not be drawn at all; but a map is still on a projection even when a graticule is not shown. Objection could be raised also to the limitation to “plane surface”, since we may speak of the projection of the spheroid upon a sphere, or of the sphere upon a hemisphere. Hence, it is suggested that “any systematic method of representing the whole or a part of the curved surface of the Earth upon another (usually plane) surface” is an adequate definition of a map projection. 相似文献
3.
《制图学和地理信息科学》2013,40(1):49-57
Many cartographers subscribe to the view that unclassed choropleth maps and multivariate choropleth maps exceed map readers' abilities to process visual information. This paper examines recent evidence which controverts both of these beliefs and discusses applications of a computer program, BICHOR, designed to produce unclassed bivariate choropleth maps interactively on a line plotter or CRT. The maps utilize crossed-line symbolism and putatively overcome both the quantization error inherent in conventionally classed choroplethic displays and the perceptual difficulties associated with color-encoding schemes used for earlier bivariate maps. 相似文献
4.
《制图学和地理信息科学》2013,40(2):192-200
Efforts within cartography on indoor maps have previously not received a lot of attention. Work that has been carried out on indoor maps often focus on map design very similar to an architectural style (Klippel et al. 2006; Ciavarella and Paternò 2004). In some cases the design has been of a more novel character where approaches with augmented and virtual realities have been carried out (Radoczky 2007; Müller et al. 2006). Common to these approaches is the depiction of one floor per map. As well, the primary user task is often solely personal navigation. In this article I present an innovative approach to indoor maps. The design is directly inspired by underground tube maps first developed by Harry Beck (Garland 1994) and today a common design for public transport maps. The main advantages of the map design are its simplicity and the possibility of including all floors in one map view. This allows the map user to easier comprehend the structure of the building without using several maps, as commonly needed with today's indoor map designs. I present several different map styles each intended to satisfy different user groups and tasks depending on the user's familiarity with the environment. In addition the article motivate for new application areas suitable for indoor maps, especially large hospitals. I hypothesize that the design proposed in this article leans very well to displaying real-time dynamic geospatial information, such as patients, staff, equipment and room availability within hospitals. Due to the early phase of the work presented here I outline the needed further work and possibilities of technological platforms as well as evaluations necessary in order for the design to gain acceptance and success. 相似文献
5.
《制图学和地理信息科学》2013,40(1):59-70
In order to create a useful map, the cartographer must select a scale at which the map reader can distinguish features shown on the map and read their labels. However, the choice of scale for a paper map is also constrained by the size of the map sheet and by the cost of working with a large number of sheets. When the feature density pattern allows, space can be conserved by making the map at more than one scale: a small scale suitable for most of the map, while dense features are shown on inset maps at larger scales. Creating inset maps requires the cartographer to make a series of complex, interrelated decisions regarding the most effective overall sheet configuration, which is dependent upon the scale chosen for the main map and how the inset maps are created. The Census Automated Map Production System (CAMPS) applies cartographic logic and density analysis to make these decisions in a fully automated mapping environment. 相似文献
6.
Andrew Curtis 《制图学和地理信息科学》2013,40(2):177-178
National Geographic Society (NGS) has made several changes throughout the years in their choice of map projection for their world reference maps. The Van der Crinten I map projection was used from 1922 to 1988. Then, in 1988, it was replaced by the Robinson projection. Beginning in 1998, the Winkel Tripel became the map projection of choice for NCS' world maps. Given this change, cartographers and others who make maps may be interested in using the Winkel Tripel for custom applications. The goal of this paper is to show how Winkel Tripel's complex projection equations can be programmed using Visual Basic. Those who use other languages such as C++ can use this programming example to help them create a similar algorithm in their language of choice. 相似文献
7.
胡毓钜 《武汉大学学报(信息科学版)》1987,(2)
本文对编制城市游览图提出了变比例尺地图投影系统。通过由普通城市平面图向辅助球面作逆投影A,再由辅助球面向平面作非A投影,构成了变比例尺地图的数学基础。由不同性质的投影的组合,能起到适应不同城市街区结构的特点。使本系统具有相当的灵活性。文中还讨论了辅助球适宜的大小和不同方位投影之间的变换公式。文末试作了北京市的变比例尺地图。 相似文献
8.
《制图学和地理信息科学》2013,40(2):132-138
Some inexpensive personal computers may be programmed to produce, at a nominal incremental cost, map projection graphics useful as educational tools. Programs have been developed to produce outline maps based on anyone of dozens of projections, in almost any aspect, at a size of up to 13.5 by 27.1 cm or 20.3 by 20.3 cm [5?by 10? in. or 8 by 8 in.]. They are printed in a dot-matrix format normally containing up to 320 by 768 dots, with alternatives of 640 by 768 or 960 by 576 dots. Available options include features such as interrupted projection, miscellaneous great or small circles, and Tissot indicatrices. The maps often require many hours to prepare, but the programs can run unattended after initial parameters have been entered. 相似文献
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10.
《制图学和地理信息科学》2013,40(3):161-180
Real cognitive maps encoded by humans are difficult to study using experimental methods because they are a product of complex processes whose content and timing cannot easily be known or controlled. This paper assesses the value of using neural network model simulations for investigating cognitive maps. The study simulated the learning of mapped city locations in South Carolina from reference sites in the three primary regions of the state using Kohonen self-organizing maps. The learning performances of models were considered based on available prior knowledge. Bi-dimensional regression analyses were used to assess the congruity of the simulated cognitive maps with a cartographic map and with sketch maps produced by human subjects. Error analyses indicated differences between central and peripheral reference sites. The cities known by subjects living at a central location were more evenly distributed in space and associated with significantly smaller errors. Models that learned combined state boundary and interstate highway information as prior knowledge or simultaneously with city locations consistently produced the best simulation results. The results indicated simulated cognitive maps could be used effectively to study the acquisition of spatial knowledge. 相似文献
11.
《制图学和地理信息科学》2013,40(4):246-254
The graticule of meridians and parallels is a largely artificial type of map boundary that can detract from the display of irregular features such as oceans. Such natural boundaries as shorelines may be used instead as the boundary of world maps. The principle of natural boundaries has been applied to several examples of equal-area or conformal world ocean maps with single or multiple lobes. By careful selection of the poles and centers, these maps can show both oceans and continents in their entirety on a single map. 相似文献
12.
《制图学和地理信息科学》2013,40(4):231-241
This paper proposes a methodology to assess gradation as a cartographic tool for communicating information in area-class maps. The communication model is used as a theoretical foundation, suggesting distinction between errors that occur in encoding and decoding of geographic information. The proposed methodology begins with the determination of a target level of encoding error. Map alternatives are constrained to achieve this target, with gradation considered as one variable in the map production process. The result is a series of maps of equal encoding accuracy but varying in the degree of gradation represented. The individual maps of the series can then be evaluated in terms of decoding accuracy. The methodology is demonstrated by producing a series of alternative forest region maps of New York, Pennsylvania, and New Jersey based on U.S. Forest Service data on tree genus distributions. The series ranges from a 4-class graded area-class map to a 13-class crisp map. The results show gradation to be a viable alternative to the proliferation of map classes as a means of cartographic communication. 相似文献
13.
为简化传统正轴等角圆锥投影求解基准纬度时繁琐的迭代算法,引入平均纬度和平均纬差的概念,借助计算机代数系统Mathematica,在平均纬差处级数展开,导出了基于球体模型的正轴等角圆锥投影求解基准纬度的非迭代算法。以全国和不同纬差的省区为例,将其与传统椭球迭代算法进行对比分析。结果表明,推导的基于球体模型的非迭代公式计算基准纬度B0、B1、B2的相对误差最大值为2.011%,长度变形的相对误差小于1×10-6,基本可满足全国以及各省区地图制图的精度要求,从而验证了所研究算法的精确性与实用性。 相似文献
14.
空间地图投影分类研究 总被引：3，自引：0，他引：3
为了进一步完善空间地图投影的系统理论，对空间地图投影进行了科学分类，主要是借鉴静态地图投影的分类研究成果，介绍按4种不同投影性质对空间地图投影进行科学分类的方法。 相似文献
15.
《测量评论》2013,45(15):16-23
AbstractTHE formula for the projection is based upon the spherical assumption. To calculate it for the spheroid might be very complicated and would not be worth while. The projection is suitable for very large areas as a compromise between the Zenithal Equal-area projection on the one hand and the Zenithal Equidistant or Zenithal Orthomorphic on the other. Its application to an area as small as the British Isles would not serve any useful purpose. An analysis of its errors in the general case reveals some unexpected simplicities. This analysis is given below, followed by its application to the particular case of the British Isles on the ten-mile scale. This is done merely to find out what changes would have occurred if the supposed drawing of that map on Airy's projection had been real. 相似文献
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17.
Richard Barnes 《International Journal of Digital Earth》2020,13(7):803-816
ABSTRACT Spatial analyses involving binning often require that every bin have the same area, but this is impossible using a rectangular grid laid over the Earth or over any projection of the Earth. Discrete global grids use hexagons, triangles, and diamonds to overcome this issue, overlaying the Earth with equally-sized bins. Such discrete global grids are formed by tiling the faces of a polyhedron. Previously, the orientations of these polyhedra have been chosen to satisfy only simple criteria such as equatorial symmetry or minimizing the number of vertices intersecting landmasses. However, projection distortion and singularities in discrete global grids mean that such simple orientations may not be sufficient for all use cases. Here, I present an algorithm for finding suitable orientations; this involves solving a nonconvex optimization problem. As a side-effect of this study I show that Fuller's Dymaxion map corresponds closely to one of the optimal orientations I find. I also give new high-accuracy calculations of the Poles of Inaccessibility, which show that Point Nemo, the Oceanic Pole of Inaccessibility, is 15?km farther from land than previously recognized. 相似文献
18.
《制图学和地理信息科学》2013,40(3):167-182
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
19.
Shapes on a plane: evaluating the impact of projection distortion on spatial binning 总被引：1，自引：0，他引：1
ABSTRACTOne method for working with large, dense sets of spatial point data is to aggregate the measure of the data into polygonal containers, such as political boundaries, or into regular spatial bins such as triangles, squares, or hexagons. When mapping these aggregations, the map projection must inevitably distort relationships. This distortion can impact the reader’s ability to compare count and density measures across the map. Spatial binning, particularly via hexagons, is becoming a popular technique for displaying aggregate measures of point data sets. Increasingly, we see questionable use of the technique without attendant discussion of its hazards. In this work, we discuss when and why spatial binning works and how mapmakers can better understand the limitations caused by distortion from projecting to the plane. We introduce equations for evaluating distortion’s impact on one common projection (Web Mercator) and discuss how the methods used generalize to other projections. While we focus on hexagonal binning, these same considerations affect spatial bins of any shape, and more generally, any analysis of geographic data performed in planar space. 相似文献
20.
日照投影是将地球被阳光照射的状态绘制在平面上,使得地图和时间建立了联系。日照正射方位投影保持了地球的圆弧轮廓,逼真地表现出了昼、夜半球。基于坐标系的变换,给出了实现日照正射方位投影的原理,并推导出了投影方程。 相似文献