Known unknowns — Knowledge in the presence of unknowns

With ever increasing complexities and a component-based design style there is a growing number of unknowns (e.g., at the interface of components) and their handling becomes more and more important in electronic design automation (EDA) and production processes. Methods and tools are required that in principle allow a modeling of unknowns balancing between exactness of representation and efficiency of calculation. We highlight state-of-the-art approaches that enable an efficient and successful integration of unknown values using formal techniques in the areas of Test and Verification/Validation.