Disclosed herein is footwear for three-beat rhythm walking. An electric storage system includes a lithium-ion capacitor unit and a lead-acid battery connected in parallel with a load, and a voltage detecting section that detects the voltage of the lithium-ion capacitor unit. Once the model has been positioned at the point in the three-dimensional data set at which the structure to be segmented is situated and positions of nodes have, if necessary, been changed by known methods of segmentation, any desired nodes can be displaced manually.