【作者】 陈杰；

【导师】 邓敏； 李光强；

【作者基本信息】 中南大学 ， 地图学与地理信息系统， 2009， 硕士

【摘要】 地图信息的定量度量是地图制图学领域中的一个重要问题,也是分析、评价地图制图质量的基础。它不仅有助于理解空间信息的特征,而且对有效地利用空间信息也是十分重要的。本文回顾了国内外相关研究成果,指出了现有研究中存在的主要问题和不足之处,并紧紧围绕着地图信息度量这一主题在理论和方法上进行了较为深入的研究,主要工作包括:(1)研究了基于分形维数的地图信息度量方法。首先,将地图信息度量分为三个层次:目标层次(即单个目标信息度量)、类层次(即一组目标的信息度量)、地图层次(即一幅地图的信息度量)。然后,针对单个目标计算方法存在的不足,本文提出一种基于buffer分形维数计算方法(缓冲区法),该方法与现有的计盒法、步长法不同,它不涉及计盒法中起始盒子位置和步长法中曲线起始点位置的选择。在一定程度上,可视为一种基于整体的计算方法。进而,探讨了类层次和地图层次的分形维数计算。(2)针对现有的基于信息熵的地图信息度量方法存在的问题,提出了一种新的地图信息分类和度量方法。该方法分别从几何、专题、拓扑以及专题拓扑四个方面来度量地图空间信息。然后,利用膨胀和序贯膨胀形态学算子分别对地图上一组线目标、面目标和一幅地图进行信息度量,并且分析了几何信息熵、专题信息熵、拓扑信息熵以及专题拓扑信息熵随地图符号影响范围不同而引起的变化。从计算结果中可以直观地看出:利用Voronoi图计算得到的结果是本文方法的一个极值结果(即特例),并且本论文提出的方法便于定量分析地图空间信息熵随符号影响范围(或大小)的变化情况。最后,总结了本文的研究成果,并展望了该方向进一步研究的若干问题。更多还原

【Abstract】 To measure map information is one of key issues in the field of cartography, and is aslo the basis of analyzing, evaluating the quality of cartography. It is not only important for further understanding characteristics of map information, but also for the effective use of map information. This paper develops some quantitative methods for the measurement of map information. These methods can be used to evaluate cartographic quality, generalization algorithms, and the transferring of map information. After reviewing relevant research progress and pointing out the existing problems and deficiencies, this paper systematically studies the measurement of map information in theories and methods. Main works are summarized as follows:(1) From the view of spatial complexity, this paper utilizes the fractal dimension to measure map information, which is respectively considered from three levels, i.e., object level, class level and map level. Then, a new method is proposed, which is based on a series of buffering operation, so it is named a buffering-based method. Unlike box-counting method and walking dividers method, the buffering-based method does not involve the location of starting box and the choice of starting point on curve. To large degree, the buffering-based method is built upon object itself.(2) From the view of the distribution of spatial objects, this paper firstly makes a critical examination of the existing approaches for map information measurement. And then, a reclassification of contents of map information is made from the consideration of geometric, thematic, topological and thematic topology. The corresponding measurements are further developed, including geometric information entropy, thematic information entropy, topological information entropy and thematic topological information entropy. On this basis, the morphology operators, i.e. dilation and sequential dilation, are used to analyze the changes of map information with the influence space of map symbols. Then it has been shown by two examples, a group of simple lines and areas, which the result obtained by Voronoi diagram is an extreme value of those by the proposed method in this paper. Indeed, our method is able to provide a series of entropy measures with different times of dilations for map symbols.Finally, this paper summarizes main findings, and highlights further research directions in the near future.更多还原