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1.
变比例尺城市平面地图通常应用一般的城市平面地图编制。因此变比例尺地图所需要的地图投影实际是两平面之间的变换。本文提出一种采用过渡球面的方法:首先把一般城市平面地图表示于过渡球面上,然后把过渡球面表示于平面上成为变比例尺地图。两次投影可以分别采用现有的各种地图投影。因此这种变换的种类是很多的。本文论述了逆等距方位投影——正射透视投影、逆等距方位投影——等角横圆柱投影和逆等距切圆柱投影——普通多圆锥投影等三种变换,并导出了长度比公式。同时还指出,平面上的方格网经逆等距切圆柱投影后,其横线和纵线分别成为过渡球面上的经线圈和纬线圈。因此方格网可以进一步变换成为和现有的某一种地图投影经纬线网图形一样的曲线网。  相似文献   

2.
变比例尺城市旅游地图的理论探讨   总被引:1,自引:0,他引:1  
张传明  焦健 《测绘通报》2005,(10):44-47
随着城市规模的不断扩大,城市旅游地图所要表示的范围也越来越大,对于固定幅面的纸质地图则增加了市中心道路的密集程度,使浏览变得困难.针对不同形式的城市路网,提出几种适合它们的变比例尺投影数学模型,并在实践中以北京市区为制图对象,进行变比例尺地图投影的尝试.  相似文献   

3.
变比例尺地图投影及其应用初探   总被引:1,自引:1,他引:1  
在介绍变比例尺投资基本原理、方法和应用的基础上,着重分析限制其应用的主要原因,提出利用计算机地图制图技术提高变比例尺投影地图制作效率的新方法。最后,对变比例尺地图投影技术在地理信息系统(GIS)中的应用前景作了展望。  相似文献   

4.
闫超德  郭王  白建军  赵姗  武舫  贺添 《测绘科学》2014,(3):34-36,44
本文详述了基于过渡曲面二次投影制作变比例尺纸质地图的方法及特点,以及通过分带连续变比例尺函数制作变比例尺电子地图的方法及特点,并针对导航设备及便携式移动信息设备,介绍了圆形与方形变比例尺地图模型、基于ROI和焦点区域的道路网变比例尺模型和基于邻近关系的自适应变比例尺地图模型。  相似文献   

5.
一类可调放大镜式地图投影   总被引:1,自引:0,他引:1  
王桥  胡毓钜 《测绘学报》1993,22(4):270-278
提出了一类新的变化比例尺地图投影,它具有“放大镜“的效果,可将地图上的重点地区、内宁可用较大比例尺放大表示出来而周围地区的比例尺不变。“放大镜“的边界及其形状、“放大“的方式、幅度亦可自由设计、灵活调整。此类投影可以基本概括现有的变比例尺投影,并克服了现有方法的诸多缺陷,产生更佳、更广泛的结果。  相似文献   

6.
变比例尺可视化技术是当今地图可视化技术发展的热门方向。提出了一种基于地图投影思想来实现大比例尺地图的变比例尺可视化的改进方法,并利用此方法通过Matlab(R2008a)实现了大比例尺地图的变比例尺显示,得到了不错的效果。  相似文献   

7.
通过对我国现行世界地图上比例尺的差异化与地图投影的关系进行初步分析和研究,总结了比例尺在世界地图上的一些变化规律。结果表明,地图比例尺差异与比例尺的大小成反比、与地图投影变形成正比,比例尺差异化问题与地图选择的投影方式、地图的逐级缩编等因素有着直接的关系。  相似文献   

8.
导航电子地图的变比例尺可视化   总被引:2,自引:1,他引:2  
将变比例尺可视化技术应用到导航电子地图可视化中,实现了“近大远小”的“哈哈镜”显示效果。设计了图形、矩形两种不同放大区域,讨论了不同比例尺区域目标的自适应可视化,并根据变比例尺地图变形特点,对距离量算方法进行改进,以克服该种可视化地图距离感弱的缺点。  相似文献   

9.
本文提出了一组新的具有“放大镜”效果的方位投影,它适用于突出重点地区而以其周围地区衬托的地图。在此组投影上,包围重点地区的圆的内部是一个标准等距或兰勃特等面积方位投影。在该圆与外围圆之间,方位角保持正确,而向径或面积比例尺分别地保持为常数,但缩小了一个定值。在其他四个投影上,其内部是一标准方位投影,可能是球面、球心或上述两者,但该部分之外向径比例尺逐渐缩小到零。带有矩形界线的这类投影也是存在的。  相似文献   

10.
军事网格参考系统(MGRS)是基于通用横墨卡托(UTM)投影面上或通用极球面(UPS)投影面上,附加在美军地图上的两组分别平行于投影坐标轴且垂直相交形成的方格网。论文较详细剖析了MGRS的网格基准、分区、编码、多分辨率网格构成及其MGRS在军事上的应用,为我国基本比例尺地形图方里网建立与完善,基于平面的地理空间信息多级网格构建提供了一些启发与思考。  相似文献   

11.
An adaptable equal-area pseudoconic map projection   总被引:1,自引:1,他引:0  
Equivalence (the equal-area property of a map projection) is important to some categories of maps. However, unlike conformal projections, completely general techniques do not exist for creating new, computationally reasonable equal-area projections. The literature describes many specific equal-area projections and a few equal-area projections that are more or less configurable, but flexibility is still sparse. This work describes a new, highly configurable equal-area projection system consisting of arcs of concentric circles, placing it in the pseudoconic class. The system uses a novel technique to hybridize the Bonne pseudoconic projection and the Albers conic projection, subsuming many existing projections as degenerate cases. With the resulting system and the technique used to develop it, map projection designers will have greater choice in tailoring the projection to the need. The system may be particularly suited to maps that dynamically adapt to changing scale and region of interest, such as required for online maps.  相似文献   

12.
Equivalence (the equal-area property of a map projection) is important to some categories of maps. However, unlike for conformal projections, completely general techniques have not been developed for creating new, computationally reasonable equal-area projections. The literature describes many specific equal-area projections and a few equal-area projections that are more or less configurable, but flexibility is still sparse. This work develops a tractable technique for generating a continuum of equal-area projections between two chosen equal-area projections. The technique gives map projection designers unlimited choice in tailoring the projection to the need. The technique is particularly suited to maps that dynamically adapt optimally to changing scale and region of interest, such as required for online maps.  相似文献   

13.
A series of new equal-area map projections has been devised. Called Oblated Equal-Area, its lines of constant distortion follow approximately oval or rectangular paths instead of the circles of the Lambert Azimuthal Equal-Area projection or the straight lines of the Cylindrical Equal-Area projection. The projection series permits design of equal-area maps of oblong regions with less overall distortion of shape and scale than equal-area maps on other projections.  相似文献   

14.
以常用地图投影为基础,通过组合投影方法,得到一类新的变比例尺地图投影。该研究开拓了常用地图投影的功能和应用范围,获得了系统的理论结果和应用实例。  相似文献   

15.
The adaptive composite map projection technique changes the projection to minimize distortion for the geographic area shown on a map. This article improves the transition between the Lambert azimuthal projection and the transverse equal-area cylindrical projection that are used by adaptive composite projections for portrait-format maps. Originally, a transverse Albers conic projection was suggested for transforming between these two projections, resulting in graticules that are not symmetric relative to the central meridian. We propose the alternative transverse Wagner transformation between the two projections and provide equations and parameters for the transition. The suggested technique results in a graticule that is symmetric relative to the central meridian, and a map transformation that is visually continuous with changing map scale.  相似文献   

16.
The Robinson projection is one of the most preferred projections for world reference maps in atlas cartography. The projection is constructed from Robinson's look-up table since there are no analytical formulas. This deficiency has led to a number of requests for the plotting formulas to which cartographers have responded by deriving analytical equations using different interpolation algorithms applied to Robinson's table values. The Robinson projection was examined with regard to its deformations calculated by four different algorithms, including the multiquadratic method. The numerical evaluations were then used to compare the algorithms. Solutions have been presented including some criticisms about this projection. The latitudes along which the scale is true and on which the maximum angular distortion equals zero have been determined.  相似文献   

17.
《测量评论》2013,45(60):217-219
Abstract

Map 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   

18.
针对球体横墨卡托投影与基于地球椭球体的导航设备结合使用存在误差以及传统椭球横墨卡托投影依据经差分带不适用于极区的问题,在分析双重投影可用于极区存在计算奇异和计算溢出问题的基础上,研究了一种基于双重投影的横墨卡托投影极区应用改进方法。首先利用函数等效变换和经线长度比计算公式推导出椭球投影到球体上的坐标变换、球体半径和长度比计算公式,然后利用分段函数的方法研究了球体横墨卡托投影计算公式,综合两个阶段给出了完整的坐标变换公式和长度比计算公式,最后推导了子午线收敛角计算公式。理论分析和算例仿真表明,该改进方法能够解决极区投影计算奇异和计算溢出问题,近极点地区长度变形较小,且与导航设备采用的地球模型一致,可消除由于地球模型不同引起的误差,提高航海绘算精度。  相似文献   

19.
The qibla problem—determination of the direction to Mecca—has given rise to retro-azimuthal map projections, an interesting, albeit unusual and little known, class of map projections. Principal contributors to this subject were Craig and Hammer, both writing in 1910. A property of retro-azimuthal projections is that the parallels are bent downwards towards the equator. The resulting maps, when extended to the entire world, thus must overlap themselves. An unusual recent discovery from Iran suggests that Muslims might have been prior inventors of a similar projection, by at least several centuries. A later corollary by Schoy leads to a new "cylindrical" azimuthal map projection with parallels bending away from the equator, here illustrated for the first time.  相似文献   

20.
《测量评论》2013,45(32):66-67
Abstract

The projection in question is a mean between Mercator's and the Equal-Area Cylindrical Projection which is formed by orthographic projection from the sphere upon the circumscribing cylinder. Both projections are computed on the spherical assumption. Mercator's Projection is, of course, the best known of the orthomorphic group; the Equal-Area Cylindrical Projection is the simplest of the equal-area group. Each projection may be said to represent an extreme case; and the mean between them may perhaps, for some purposes, be a useful compromise.  相似文献   

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