Weichang Qian or Weizang Chien, Chinese physicist (Wuxi County, Jiangsu Province 09 October 1912 – Shanghai 30 July 2010)

Authored over 200 papers and 18 monographs

Studied new generalized variational principles and established a new variational functional

Suggested using the Lagrange multiplier for eliminating the constraint conditions of all kinds of variational problems and established a new variational function using it 

Put forward a systematic method to construct generalized variational principles (1964) published only in 1979

Introduced the intrinsic methods in elasticity (1944)

With J.L. Synge authored a pioneering classical work on the intrinsic theory of plates and shells in solid mechanics

Established the complete intrinsic theory of plates and shells (1942)

Proposed a method to calculate the resistance of radar-wave guides

Perturbation theory (1947)

Developed the method of composite expansions, a novel singular perturbation method (1948)

Initiated a perturbation method by using the central deflection as ther perturbation parameter

Solved the variable twist torsion problem of thin-walled cylinders with closed cross sections

First to obtain the limit equation for thin ring shells and the general solution to the homogeneous equation 

Developed a new field of non-Kirchhoff-Love theory of plates and shells 

Derived a general solution for axisymmetric circular ring shells

Developed a new method of encoding Chinese characters (1984)

EPONYMY

Successive approximation method of treating large deflection problem or Chien method (1948)

Qian Weichang equation for nonlinear stability of shallow shell (1960s)

Qian Weichang general equation