中文摘要：

提出了一种基于分维扩展理论的关键比例尺确定方法，认为地图目标的自相似性是随着比例足的变化呈衰减趋势变化，可以反映在图面信息量的变化上，并借助分维扩展中的反“S”曲线模型来确定两个已知比例尺之间的关键比例尺。

英文摘要：

A new method for the determination of the catastrophe-scale based on the theory of the extended fractal dimension is presented. From the large-scale to the small-scale, the selfsimilarity of map object descends gradually, and reflects as the change of the map information. Make use of the extended fractal model of inverse ＂S＂ can determine the catastrophescale between two known scales.