中文摘要：

采用数学形态学图象分析处理的方法，对8字形连杆曲线进行了深入研究，发现了8字形连杆曲线形状谱的一些重要特征。在计算实践，发现现有的相似度计算公式不能很好地区别不同形状的8字形连杆曲线。针对现有相似度计算公式在区别不同8字形连杆曲线上存在的问题，提出了8字形连杆曲线扭曲角的新概念，对相似度计算公式进行了修改，最后用更多的实例验证了修正公式的有效性。

英文摘要：

Using the image-processing method of mathematical morphology, we study in depth an 8-shaped linkage curve and discover some of the important features of its shape spectrum. In calculating the shape spectrum, we find that the existing equation for calculating conformity degree does not well distinguish the 8-shaped linkage curve. Accordingly we put forward the new concept of warp angle and modify the equation for calculating the conformity degree. Finally we use more instances to verify the modified equation.