Departmental Papers (CIS)

Date of this Version

July 2006

Document Type

Journal Article


In this paper,we develop a theory of modular design and refinement of hierarchical hybrid systems. In particular, we present compositional trace-based semantics for the language CHARON that allows modular specification of interacting hybrid systems. For hierarchical description of the system architecture, CHARON supports building complex agents via the operations of instantiation, hiding, and parallel composition. For hierarchical description of the behavior of atomic components, CHARON supports building complex modes via the operations of instantiation, scoping, and encapsulation. We develop an observational trace semantics for agents as well as for modes, and define a notion of refinement for both, based on trace inclusion. We show this semantics to be compositional with respect to the constructs in the language.

Subject Area

CPS Real-Time, CPS Model-Based Design

Publication Source

Journal of Logic and Algebraic Programming





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Copyright/Permission Statement

NOTICE: This is the author’s version of a work that was accepted for publication in The Journal of Logic and Algebraic Programming. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms, may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in The Journal of Logic and Algebraic Programming, Volume 68, Issues 1-2, June-July 2006, DOI: 10.1016/j.jlap.2005.10.004.


Hybrid Systems, Formal Methods, Compositional semantics, Model refinement



Date Posted: 20 August 2006

This document has been peer reviewed.