In the paper, the authors present the approach to modelling of austenitic steel hardening basing on the Frederick-Armstrong’s rule and Chaboche elastic-plastic material model with mixed hardening. Non-linear uniaxial constitutive equations are derived from more general relations with the assumption of an appropriate evolution of back stress. The aim of the paper is to propose a robust and efficient identification method of a well known material model. A typical LCF strain-controlled test was conducted for selected amplitudes of total strain. Continuous measurements of instant stress and total strain values were performed. Life time of a specimen, signals amplitudes and load frequency were also recorded. Based on the measurement, identification of constitutive equation parameters was performed. The goal was to obtain a model that describes, including hardening phenomenon, a material behaviour during the experiment until the material failure. As a criterion of optimisation of the model least square projection accuracy of the material response was selected. Several optimisation methods were examined. Finally, the differential evolution method was selected as the most efficient one. The method was compared to standard optimisation methods available in the MATLAB environment. Significant decrease of computation time was achieved as all the optimisation procedures were run parallel on a computer cluster.

In the paper the problem of optimum experimental design for estimating parameters of multivariate regression functions is considered. We address the question: under what conditions one can compose the optimal design from partial designs, obtained by considering partial regressions, which depend on reduced number of variables. After reinterpreting and reviewing briefly existing results we provide some new conditions

Ksiazka jest przewodnikiem po oprogramowaniu systemu obslugi eksperymentu /soe/ zrealizowanego w ramach programu resortowego rr i. 14, i oprogramowaniu systemowym wspomagania eksperymentu. Moze byc ona takze pomocna przy rozbudowie zoe lub przy tworzeniu przez uzytkownika wlasnych wersji oprogramowania komputerowego wspomagania eksperymentu /kwe/. Ksiazka jest przeznaczona dla osob zajmujacych sie badaniami eksperymentalnymi, ktore nie specjalizuja sie w informatyce i statystycznej obrobce danych. Merytoryczne opisy algorytmow moga zainteresowac specjalistow z poszczegolnych dziedzin.

In the note Hoel’s result (1965, Ann. Math. Statist., 36, 1097- 1106) is generalized to a large family of experimental design optimality criterions. Sufficient conditions for optimality criterion are given, which ensure existence of the optimum experimental design measure which is a product of design measures on lower dimensional domains.