Formal verification increasingly has become recognized as an answer to the problem of how to create ever more complex control systems, which nonetheless are required to behave reliably. To be acceptable in an industrial setting, formal verification must be highly algorithmic; to cope with design complexity, it must support a top-down design methodology that leads from an abstract design to its detailed implementation. That combination of requirements points directly to the widely recognized solution of automata-theoretic verification, on account of its expressiveness, computational...