Quality assurance and control (QAC) of uncertainty models and simulations of life cycle assessment (LCA)

The life cycle analyst in systems engineering and environmental engineering is associated with large uncertainties, being of a forecasting or predictive nature. Various approaches are used to estimate trends in the life cycle, either by its probabilistic nature or by fuzzy variables. Regardless of the approach, the models are used for decision support and need to be assured and controlled for their quality in describing the real situation. This paper draws attention to this problem, and suggests methods for cross-checking simulation models, by various methods based on underlying fundamental principles, asymptotic conditions, average properties, submodel interrelations, etc. A generic systems engineering principles approach is used in developing the model of the life cycle. This approach is based on analyses and justifications of needs and a definition of requirements for the model and its simulation results.