2 September 2004A Brief Report on the Workshop on Structural Operational Semantics
On August 30, 2004, I was in London, United Kingdom, for the Workshop on Structural Operational Semantics that I co-organized with Wan Fokkink and Irek Ulidowski. This was one of the pre-conference workshops affiliated with CONCUR 2004, and was held concurrently with five other events in the beautiful setting of the Royal Society. (The room that was allocated to us hosted a table that had belonged to Robert Hooke, the first Curator of Experiments of the Royal Society!)
Irek, Wan and I had originally been a bit worried about the event, as we had received only seven submissions to the workshop. We chose, however, to uphold a high scientific standard, and selected three papers for presentation at the workshop and for inclusion in the proceedings. Since the workshop also marked the the publication of a special issue of the Journal of Logic and Algebraic Programming devoted to SOS edited by Wan and me, we decided to invite several of the contributors to that volume to deliver presentations at the workshop based on their special issue papers. All registered workshop participants received a copy of the special issue, courtesy of Elsevier. Moreover, thanks to a grant from the Engineering and Physical Sciences Research Council (EPSRC) arranged by Irek, we were able to fund the participation of some U.K-based PhD students.
Of course I am biased, but I believe that the workshop was a success, both scientifically and socially. We had about 30 participants1 who attended essentially the whole workshop, and the level of the talks was consistently very high. Apart from some initial technical problems, that we shared with all of the other workshops, the day went smoothly, and was rounded up by a relaxed and pleasant workshop dinner in a good Chinese restaurant in Soho.
The scientific programme for the workshop was kicked off by Andrew Pitts, who delivered a beautifully paced talk in which he surveyed his work on a lightweight theory of structural recursion and alpha-congruence for languages that involve binders that is close to common nominal practices. His proposal involves the use of Fraenkel-Mostowski permutation model of set theory with atoms, and is being embodied in the FreshML research project. Look also at the slides of Andy's talk for more details.
The programme included two very clear tutorials by David Sands and Rob van Glabbeek that were aimed at PhD students. (I for one, however, still learned much from them, and probably should have learned more.) David showed how the use of a higher-order syntax representation of contexts combines smoothly with higher-order syntax for evaluation rules, so that definitions can be extended to work over contexts, and argued that this leads to a useful technique for directly reasoning about operational equivalence. Rob gave an entertaining and interactive whiteboard based presentation of his work on how to assign meaning to transition systems specifications with negative premises. (I am proud to say that, with the help of a few attendees, Rob and I managed to carry the whiteboard over a flight of stairs without damaging the walls or paintings in the Royal Society!)
The three interesting contributed talks were delivered by Matthias Mann, Olivier Tardieu and Marija Kulas. Matthias presented his difficult result on the congruence of bisimulation in a non-deterministic call-by-need lambda calculus. (Look here for the slides.) Olivier gave a talk on his new deterministic logical semantics for Esterel. Marija's talk on the other hand described a structural operational semantics for Prolog that can handle backtracking.
The scientific programme was completed by two special issue talks delivered by two researchers affiliated with BRICS, namely Bartek Klin and Peter Mosses, and one by Ralf Laemmel. Bartek gave a very lucid account of his work on the derivation of congruences from bialgebraic semantics. (You can find the full story in his doctoral dissertation.) Peter gave a talk on Modular SOS, an approach to making SOS semantic descriptions usable for describing the semantics of full-blown programming languages in a modular fashion. Ralf closed the workshop with a well attended talk on evolution scenarios for rule-based implementations of language-based functionality in which he presented his software Rule Evolution Kit.
Overall, we ended the day tired, but feeling that it would be a good idea to organize a second edition of the workshop some time next year.
List of Participants to the Workshop: Luca Aceto (Denmark), Joey Coleman (UK), Paulien de Wind (The Netherlands), Adam Eppendahl (UK), Wan Fokkink (The Netherlands), Adrian Francalanza (UK), Rachele Fuzzati (Switzerland), Rob van Glabbeek (Australia), Andy Gordon (UK), Benjamin Hirsch (UK), Bartek Klin (UK), Marija Kulas (Germany), Ralf Laemmel (The Netherlands), Paul Levy (UK), Matthias Mann (Germany), Jose Manuel Mendez (Spain), Peter Mosses (Denmark), Evelyn Pacanza (Philippines), Andrew Pitts (UK), Gemma Robles (Spain), David Sands (Sweden), Sam Staton (UK), Olivier Tardieu (France), Alwen Tiu (France), Irek Ulidowski (UK), Christian Urban (UK), Daniele Varacca (France), Hiroshi Watanabe (Japan), Axelle Ziegler (France).
1 To put this number of participants into perspective, and have an idea of the difficult choices that the attendees of the pre-conference workshops had to make, it suffices only to note that Rob van Glabbeek, Chris Hankin, Andrew Pitts, Corrado Priami and Julian Rathke were delivering invited talks concurrently in the morning session, and Rocco De Nicola, Andrew Finney, Rob van Glabbeek, Roberto Gorrieri and Uwe Nestmann were speaking at the same time in the afternoon! Which talks would you have chosen? As organizer of one of the workshops, I was left without a choice, and maybe that was just as well!
Last modified: Tuesday, 07-Sep-2004 15:30:53 CEST.