Multi-objective modeling for engineering applications: DIDASN++ system

Modeling and simulation of various physical, technical, environmental or socio-economic processes is often a preliminary step for using the resulting models in computer-aided design or decision support. In engineering computer-aided design, the decisions of the designer might be supported by multicriteria optimization – which in this case should be considered as a tool for supporting the final choice of the design, but much more as a tool for helping in a flexible analysis of various design options or even various modeling and simulation options. The paper shows how multicriteria optimization techniques can be used for multi-objective analysis of a model from the beginning stages of model construction. With the advancement of computing technology and the methodology of decision support, it is now possible to revise this way basic approaches to modeling and simulation. Various formats of defining nonlinear and time-discrete models are discussed together with related problems of inverse and softly constrained multi-objective simulation. Algebraic differentiation and sensitivity analysis, fuzzy set representation of modeler preferences are also useful techniques of multi-objective modeling. Such techniques are illustrated by engineering applications of a software package DIDASN++ in mechanics and automatic control.