Solving inverse viscoelasticity problems via aggregate function approach

This paper presents a nonlinear programming model with multi-constraints of inequality to solve inverse viscoelasticity problems. By utilizing an aggregate function approach, multi-constraints are converted into a single smooth constraint. The optimization with a single constraint is realized by using a technique of multiplier penalty functions, and a standard BFGS algorithm is employed in the solution process. Results with time dependent and independent noise data are given.