Identification of material parameters from punch stretch test

To accurately describe the mechanical properties of aluminium alloy sheet during deformation, an inverse identification was presented to deal with material parameters from the popular punch stretch test. In the identification procedure, the optimization strategy combines finite element method （FEM）, Latin hypercube sampling （LHS）, Kriging model and multi-island genetic algorithm （MIGA）. The proposed approach is used on material parameter identification of aluminium alloy sheet 2D12. The anisotropic yield criterion Hill’90 is discussed. The results show that the Hill’90 anisotropic yield criterion with identified anisotropic material parameters has a good potential in describing the anisotropic behaviours. It provides a way to obtain the material parameters for FE simulations of sheet metal forming.

古汉诗英译本的“形”与“神”反合观

从反合论角度而言,在古汉诗英译过程中,形似型译文重“形”而轻“神”,强调语言形式与原文等值,但忽略了古汉诗的本质文化意象的塑造,译本“形合神离”使得“形”与“神”处于相互对立关系,贴切度表现为关系相反的语言表征;神似型译作重“神”而轻“形”,不太讲究格律对仗等诗形,但可再现原诗的文学性效果,其“形离神合”构成以“神”为主、以“形”为辅的相互辩证关系,贴切度具有互补相反的反合表征;形神相似型译文则是“形”与“神”的统一连续体,由于语言思维与民族心理上的差异,译本在贴切程度上表现出不同变化,存在着程度相反的反合关系。