https://nhuantranduc.dev/blog All about Data and Artifical Intelligence en-us tranducnhuan@hotmail.com (Steve Tran) tranducnhuan@hotmail.com (Steve Tran) Sun, 31 May 2026 00:00:00 GMT https://nhuantranduc.dev/blog/til-curves-of-constant-width https://nhuantranduc.dev/blog/til-curves-of-constant-width Today I learned that manholes are round because of 'curves of constant width' — a mathematical concept Euler discovered in 1771, 100 years before engineers needed it. Sun, 31 May 2026 00:00:00 GMT tranducnhuan@hotmail.com (Steve Tran) TILmathematicsengineeringgeometryinfrastructure