政区地图设色方案的自动实现

分析了政区地图的设色要求 ,阐述了色彩设计中的对比调和理论 ,以此为依据设计出相应色环 ,规定一种间色 ,在色环中确定这种间色的对比色和类似色的CMY配色值 ,依据一定的顺序 ,自动把颜色配置在全国政区图上 ,并对自动设色和人工设色结果进行了比较分析 ,表明在可视化环境中 ,自动设色的地图比没有或仅有较少制图知识的人设计出的地图工效高     

关于网点和网线表现平网问题的探讨

在地图制印方面很早以前都是专色制版和印刷,这在大部分都是线划版的情况下用专色还是合理的。但是对很多种类的彩色地图如政区图等都是区域设色,并且用色较多,又如地质图多至数十个色,这些多色制印,延长了出版时间,提高了成本,因此有关方面对地图制印都在研究推广使用四色制印。推广使用四色制印这很好,但都用网点表现色调就值得考     

顾及视觉规律的行政区划图自动着色回溯法

行政区划图着色需要顾及区域配置、色彩平衡和用户意图等。本文从视觉规律出发,在给定配色模板前提下,研究了图面色彩协调、色彩对比和视觉平衡的定量化方法,并建立了行政区划图着色效果的评价模型。在此基础上,本文提出了行政区划图自动着色的面积均衡约束回溯法。试验结果表明,本方法能较好地顾及行政区划图着色过程中的视觉规律,满足制图要求。     

平均海拔与平均坡度图的编制及其应用

一、平均海拔地势图的编制地面高度与坡度是组成地貌特征的两个基本因素。在中、小比例尺地图上较大范围内表示地势高低的主要方法是等高线加分层设色，另一方法是利用各个制图单元的平均海拔分级着色。它的编图资料来源取决于在大、中比例尺地图上进行分高度带的面积量测。根据地形图已有的等高线，分别量测每个经纬网梯形内各制图单元（分政区、水系，或按其它指标划分的统计单元）所含高度分带（如每隔100～200m的海拔分带）的面积。量测成果能准确揭示各地海拔高度的空间分布差异，它既是进行农业规划、国土整治及建立地理信息系统所必…     

三维地图的机助制图试验

作者指出三维地图正在逐渐得到广泛使用,其原因是:1.许多制图物体具有三维表面,而就制图手段而言,三维地图能显示所表示物体的本来面目。2.从地图感受论来说,用透视方法制成的地图能较好地符合人们对实在的观察,因此这种地图具有更多的直观性而读者能便于获得具体印象。其次这种地图易于用机助制图方法制作。本文中指出若干不同题材的三维地图例子。是在美国北达科他州立大学地理系实验室用 IBM 370/158计算机和 Calcomp 自动绘图机用机助制图方法完成的。     

分级瓦片地图自动渲染制图规则设计与实现

目前瓦片地图是最普遍的网络地图形式,该技术用金字塔模型组织的地图瓦片模式代替了传统的Web GIS地图模式,大大提高了网络地图的响应速度。网络地图现势性要求高、比例尺跨度大,这些对瓦片地图制作和更新效率提出了更高的要求。本文研究了以多比例尺矢量基础地理信息数据库为数据源,通过自动渲染技术制作分级地图瓦片的方法。该方法已在不同区域导航图瓦片试生产中得到验证和完善,形成了一整套分级瓦片地图自动渲染制图规则,实现了矢量数据到瓦片地图的自动成图,减少了人工作业量90%以上,人工作业主要用于完成数据原始错误修改、现势性更新和瓦片地图质量检查等工作。此套规则不但适用于各图种瓦片地图要素的自动渲染,其他矢量电子地图数据可视化也可参照。     

顾及制图规则的地图多要素协同移位方法

在地图自动编制中,有时多类地图要素多个空间目标之间同时发生空间冲突,在移位过程中会影响到邻近区域的地图目标,这就需要对地图要素移位进行协同处理。在自动识别邻近空间冲突区的条件下,提出了一种顾及地图制图规则的解决地图目标群空间冲突的协同处理方法,并用参数表方法形式化表达了地形图上地图要素移位的常用制图规则。首先利用约束性Delaunay三角网识别出可能的空间冲突区域,并建立移位操作区;然后,建立移位传播关联线网,依据制图规则在关联线网上以能量最小化Beam移位模型为基础,对整个空间冲突区的地图目标群进行协同移位;最后,用实验验证了所提方法的有效性和适用性。     

制图自动化的数学方法

自动化制图可以看成实现计算机模拟的过程。实质上是由程序设计人员按照地图设计的要求选择的数学方法，由计算机完成对原始信息的运算处理，并通过程序控制，按排自动绘图机笔的移动，来实现图形的自动输出。因此，实现自动制图，必须建立精确描述地图内容和制作过程的数学逻辑方法，这是程序设计的前提。数学方法的精度和适用性直接影响自动制图的质量。对制图对象的分布特征和制图过程的各个环节的数学描述是一个复杂的课题。通常必须依据人们对制图对象规律的认识和制图的实践经验，总结成一套反映制图对象数量关系的数学表达式和具体算法，来描述其规律，并且不断地在运用这些数学法则和理论公式的实践过程中，加以改进和完善，逐渐形成一整套符合客观实际的公式和算法，被称为地图的“数学模式”。目前，关于用数学方法研究的制图模式，我们可以归纳为以下几个方面。     

论中小比例尺政区形式地图的更新编辑

更新编辑中小比例尺政区形式地图主要是在现有数据的基础上,充分利用现势性较好的相关资料对已有数据进行修改、补充、完善,并且在色彩和地图表现形式上进行新颖的加工处理。更新编辑过程中,涉及地图要素内容比较复杂,需要有丰富的制图经验和多层面的色彩设计理念,将地图的视觉效果和艺术价值达到较高水平[1]。更新编辑中要保证成图数学精度,还要进行制图综合,表达合理各要素关系。下面以更新编制1∶550 000辽宁省地图为例详细地介绍一下中小比例尺政区形式地图的更新编辑过程。     

四色印刷政区插图

常规政区地图的制印,一般都需要七八个颜色方能较好地反映地图的色彩效果。但用色越多,制版作业量越大,成本越高,并且用色多纸张易变形,地图质量也就难以保证。近年来,国内外地图印刷界都在致力研究减色印刷和四色印刷,并取得了可喜的成绩。但国内印图厂家还是用常规工艺的居多。地图类型繁多,用户要求各异,书中插图这一特有形式的地图对质量要求并不太高,且幅面小,印刷数量也很少,用户一般都不愿出太多的钱去印     

Searching for Boundaries on Maps: Cognitive Processes

The purpose of this research was to examine the interaction between color and the visual processes people use to search choropleth maps. Two experiments were performed in which subjects searched hypothetical choropleth maps displayed on a cathode-ray tube to determine whether a particular (target) boundary formed by two adjacent polygons filled with different colors was present. In experiment 1, the four pairs of colors used to form the target boundaries were red-blue, green-yellow, green-magenta, and cyan-magenta. In experiment 2, red-green, blue-yellow, red-orange, and cyan-orange were the color pairs used toform the target boundaries. The target boundary colors, target-background discriminability, target boundary location, and the number and types of boundaries on the maps had a significant effect on search time. The results of both experiments indicated that subjects were using a parallel search process followed by a serial search process as described by Cave and Wolfe's (1990) guided search theory. The relative mean search times for the various colored target boundaries was best explained by the opponent process theory.     

彩色扫描地形图的自动分色与处理

提出了一种基于颜色特征的地形图要素自动分层的方法，并针对地形图上的图形要素特征，提出了对等高线分版图进行后处理的算法，分析和讨论了该方法和算法的实验效果及效率。     

用标记法压缩色域

提出了一种新的色域压缩方法。用此种方法不仅能将超色域颜色压缩到目标设备的色域内,使色域内大部分颜色保护不变,而且能保证被压缩图像部分的灰色级不受损失;提出了判断色域的检测方法。试验证明,使用该检测方法处理的图像的超色域与用Photoshop中的色域警告处理的超色域非常相似。     

基于核密度估计方法的地图色域分析

针对地图制图中色彩选择较为困难的问题,该文收集国内外优秀地图、地图集、著作等上成功的设色方案,提取大量地图色彩样本。利用核密度估计方法,分析各类地图的常用色域区间,作为地图配色时的基色调。根据大量的地图色彩样本,利用定量的数学方法以及数据挖掘方法,探索地图色域特征分布规律。最后以收集的人口地图和环保地图颜色样本为例进行实验分析,对比证明本文方法能够很好地缩小地图色域选择区间,方便制图者根据地图种类选择颜色。     

The circular dataimage,a graph for high-resolution circular-spatial data

Abstract

Vectors and periodic phenomena, e.g. traffic versus time, have direction on a circular scale of 360°. An overview of existing methods for the display of circular-spatial and vectorial-spatial data, such as arrow plots, is given. We introduce the circular dataimage, a new type of graphic for the display of circular-spatial data. It is defined by encoding direction in a spatial display by using colors from a color wheel constructed by connecting three or more two-color gradients with color continuity at the connections. Therefore, image discontinuity from using a single-color gradient, e.g. blue–red, does not occur. High-resolution global views of ocean wind direction are used as a running example throughout the paper. Advantages and disadvantages of circular dataimages compared to arrow plots were obtained from a usability study. Circular dataimages provide for simultaneous recognition of fine structure on a small-scale and large-scale structure on a global scale.     

The effect of spatial distance on the discriminability of colors in maps

ABSTRACT

The spatial distance (gap) between map symbols can have a great impact on their discriminability, however, there is little empirical evidence to establish spatial and attribute thresholds. In this paper, we examine the effect of the spatial gap in discriminability of color hue and value, that is, we conducted an online study to obtain performance metrics; then an eye-tracking study to understand participants’ strategies and cognitive processes. Participants completed two experimental tasks (compare two areas and decide if their color is the same; and compare three areas and rank them from the lightest to the darkest). The color distances and the spatial distances were strictly controlled for the compared areas. Our analyses confirmed that, overall, increasing the gap between colors has a consistent negative impact on the ability to differentiate them with both sequential and qualitative schemes. Furthermore, we observed that sequential schemes require larger color distances than qualitative schemes for discriminability. Finally, our results suggested that for qualitative colors, the largest tested color distance ?E₀₀ = 10 yields considerably higher levels of accuracy in color discrimination (even when the spatial gap between the two colors is large), thus we recommend ?E₀₀ = 10 to practicing cartographers and other information visualization designers.     

Evaluating Alternative Line Simplification Strategies for Multiple Representations of Cartographic Lines

Two basic strategies have been identified for handling multiple representations of line features in digital databases. Either a finite number of scale-dependent representations of cartographic lines can be explicitly stored, or a scale-independent database is generated from which subsequent scale representations can be extracted as needed. These two strategies parallel differences in hierarchical and non-hierarchical line simplification operators. Non-hierarchical line-simplification can produce the most geometrically accurate simplification at any scale, while hierarchical operators are often associated with scale-independent databases. In this research, hierarchical and non-hierarchical line simplification operators are evaluated by comparing both the points retained by these different algorithms and the overall quality of the graphic portrayal for sample lines of different complexity and at different scales. Visual inspection of the results did not reveal any discernable difference at any scale for any line. Subsequent numerical analyses shows some differences but overall little geometric quality is lost by using a hierarchical operator as opposed to a non-hierarchical one and given the greater flexibility of scale representations that is possible, hierarchical methods appear to be more satisfactory.     

行政区划图自动着色的混合遗传算法

结合贪心算法的局部搜索能力与遗传算法的全局搜索能力,研究了政区图四色着色问题的混合遗传算法,并在此基础上提出了一些改进措施。试验结果表明,这种混合遗传算法能有效地解决行政区划图自动着色问题,并取得了较好的结果。