We propose a new method to analyse the similarity of protein CPK models. In the proposed method we first construct the skeleton of protein models by an improved L1-medial skeleton extraction. The skeleton information is then used to form a local radius descriptor. Finally, the shape similarity of protein models is compared by using the local radius descriptor based on the absolute degree of grey incidence. Experimental results show that the improved L1-medial skeleton of protein models can describe the shapes of the protein models well. The local descriptor based on the skeleton combined with the absolute degree of grey incidence shows satisfactory performance for comparing the shape similarity of protein CPK models.
Keywords: CPK model; L1-medial skeleton; local descriptor; protein model; shape similarity.