網址: https://www.researchgate.net/publication/355485316/figure/fig3/AS:1123573880098818@1644892296013/Left-The-slice-of-and-its-Convex-hull-Right-the-loop-gdocumentclass12ptminimal.png
網址2: https://www.researchgate.net/figure/Left-The-slice-of-and-its-Convex-hull-Right-the-loop-gdocumentclass12ptminimal_fig3_355485316
