What was Llull up to? -- Llull as computer scientist or why Llull was one of us -- Deductive verification of real-time systems using STeP -- Refinement of Time -- The verus language: Representing time efficiently with BDDs -- Refining interval temporal logic specifications -- Integrating temporal logics and model checking algorithms -- PLC-automata: A new class of implementable real-time automata -- Communication concepts for statecharts: A semantic foundation -- Regular processes and timed automata -- A visual formalism for real time requirement specifications -- Formal specification and verification method of concurrent and distributed systems by restricted timed automata -- Transformational formal development of real-time systems -- A transformation of monitor into communication synchronized parallel processes: A systematic refinement step in design -- Contracts for ODP -- Affine transformations in Signal and their application in the specification and validation of real-time systems -- Action-based concurrency and synchronization for objects -- Communication Extended Abstract Types in the refinement of parallel communicating processes -- Verification and refinement of distributed programs in a fair framework -- Formalizing real-time scheduling as program refinement -- Specification and refinement of continuous real-time systems -- High-level execution time analysis -- A sound and complete proof system for probabilistic processes -- Testing semantics for a probabilistic-timed process algebra -- Denotational semantics for timed testing -- Extending LOTOS with time: A true concurrency perspective -- of a suspend/resume operator in ET-LOTOS -- Specification and verification of a real-time field bus with formal description languages.

This book constitutes the refereed proceedings of the Fourth International AMAST Workshop on Real-Time Systems and Concurrent and Distributed Software, ARTS'97, held in Palma de Mallorca, Spain, in May 1997. The volume presents 24 carefully selected revised full papers. Also included are two historical contributions honoring Ramon Llull, who was born on Mallorca, as well as two invited papers. All current issues in the field of formal methods for real-time systems and distributed and concurrent systems are addressed.