VERIFICATION AND VALIDATION OF COMPLEX SYSTEMS

Verification and validation of complex system simulations are generally considered to be independent concepts. We consider the system model verified if there is a proof of the properties in question. We demonstrate that validation is a contravariant form of verification. We do this by considering the refutation tree produced by a resolution proof of the system properties. We indicate areas requiring further development. Keyword I: Complex systems Keyword II: Systems, modeling, theory, logic, theorem proving Introduction The goal of science is to explain the natural world. While some phenomena can be explained without reference to mathematics, most phenomena are modeled using mathematics (?). As our understanding increases, we can model more complex phenomena more completely . These complex models now most often require supercomputers to solve. These computational models — simulations — 1 Copyright  2002 by ASME