Yu Mao-Hong (Chinese: 俞茂宏, b. 1934) is a Chinese engineer and a university professor. He is noted for his research on the strength hypotheses and yield surfaces of isotropic materials. His unified strength theory (UST) has found acceptance as generalized classical strength theory. It contains the following nonparametric strength theories and criteria: * the normal stress theory (the William John Macquorn Rankine hypothesis), * the Tresca yield criterion, * the von Mises yield criterion (the Sokolovsky regular dodecagon in the π-plane), and * the Schmidt-Ishlinsky yield criterion