Express/SOS

Combined International Workshop on Expressiveness in Concurrency and on Structural Operational Semantics

New

Express/SOS 2025

Scope and Topics

The EXPRESS/SOS workshop series aims at bringing together researchers interested in the formal semantics of systems and programming concepts, and in the expressiveness of computational models.

Topics of interest for this combined workshop include:

  • expressiveness and rigorous comparisons between models of computation (process algebras, event structures, Petri nets, rewrite systems)
  • expressiveness and rigorous comparisons between programming languages and models (distributed, component-based, object-oriented, service-oriented)
  • logics for concurrency (modal logics, probabilistic and stochastic logics, temporal logics and resource logics)
  • analysis techniques for concurrent systems theory of structural operational semantics (metatheory, category-theoretic approaches, congruence results)
  • comparisons between structural operational semantics and other formal semantic approaches
  • applications and case studies of structural operational semantics
  • software tools that automate, or are based on, structural operational semantics

We especially welcome contributions bridging the gap between the above topics and neighbouring areas, such as:

  • computer security
  • multi-agent systems
  • programming languages and formal verification
  • reversible computation
  • knowledge representation

History

The Express workshops aim at bringing together researchers interested in the expressiveness of various formal systems and semantic notions, particularly in the field of concurrency. Their focus has traditionally been on the comparison between programming concepts (such as concurrent, functional, imperative, logic and object-oriented programming) and between mathematical models of computation (such as process algebras, Petri nets, event structures, modal logics, and rewrite systems) on the basis of their relative expressive power. The Express workshop series has run successfully since 1994 and over the years this focus has become broadly construed. The EXPRESS workshops were originally held as meetings of the HCM project EXPRESS, which was active with the same focus from January 1994 till December 1997.

The SOS workshops, whose first edition was in 2004, aim at being a forum for researchers, students and practitioners interested in new developments, and directions for future investigation, in the field of structural operational semantics. One of the specific goals of the SOS workshop series is to establish synergies between the concurrency and programming language communities working on the theory and practice of SOS. Reports on applications of SOS to other fields are also most welcome, including: modelling and analysis of biological systems, security of computer systems programming, modelling and analysis of embedded systems, specification of middle-ware and coordination languages, programming language semantics and implementation, static analysis software and hardware verification, semantics for domain-specific languages and model-based engineering.

Since 2012, the Express and SOS communities have joined forces and organised a combined Express/SOS workshop. The past combined workshops were a success, so this year there will again be a combined workshop on the semantics of systems and programming concepts, and on the expressiveness of mathematical models of computation.

2023 marked the 30th edition of Express and the 20th edition of SOS.

Steering committee

  • Johannes Borgstrom
  • Ilaria Castellani
  • Valentina Castiglioni
  • Ornela Dardha
  • Wan Fokkink
  • Rob van Glabbeek
  • Bas Luttik
  • Uwe Nestmann
  • Jorge A. Pérez
  • Kirstin Peters
  • Jurriaan Rot
  • Simone Tini
  • Claudio Mezzina