Algebra and Coalgebra in Computer Science

CALCO, the Conference on Algebra and Coalgebra in Computer Science, is a high-level, bi-annual conference formed by joining CMCS (the International WorkshoponCoalgebraicMethodsinComputerScience)andWADT(theWo- shoponAlgebraicDevelopmentTechniques).CALCObringstogetherresearchers and practitioners to exchange new results related to foundational aspects and both traditional and emerging uses of algebras and coalgebras in computer s- ence. The study of algebra and coalgebra relates to the data, process and str- tural aspects of software systems. CALCO is supervised by the Steering C- mittee, co-chaired by Jos e Luiz Fiadeiro and Jan Rutten. The ?rst two CALCO conferences took place in 2005 in Swansea, Wales, and in 2007 in Bergen, Norway. CALCO 2009, the third event in the series, took place in Udine, Italy, during September 7 10, 2009. CALCO 2009 received 42 submissions, out of which 23 were selected for presentationattheconference.Inspiteofarelativelylownumberofsubmissions, their standard was generally very high. The selection process was carried out by the Program Committee, taking into account the originality, quality and relevance of the material presented in each submission, based on the opinions of expert reviewers, four for each submission. The selected and revised papers are included in this volume, together with the contributions from the invited speakersMaiGehrke,ConorMcBride,PrakashPanangadenandGordonPlotkin.

Inhalt
Algebraic Effects and Recursive Equations.- Adequacy for Infinitary Algebraic Effects (Abstract).- Algebras for Parameterised Monads.- Kleene Monads: Handling Iteration in a Framework of Generic Effects.- Complete Iterativity for Algebras with Effects.- Semantics of Higher-Order Recursion Schemes.- Theory of Coalgebra.- Coalgebraic Components in a Many-Sorted Microcosm.- Complementation of Coalgebra Automata.- Characterising Behavioural Equivalence: Three Sides of One Coin.- Coinduction.- Let's See How Things Unfold: Reconciling the Infinite with the Intensional (Extended Abstract).- Circular Coinduction: A Proof Theoretical Foundation.- Bisimulation.- Approximating Labelled Markov Processes Again!.- Weak Bisimilarity Coalgebraically.- Coalgebraic Symbolic Semantics.- Relating Coalgebraic Notions of Bisimulation.- Traces, Executions and Schedulers, Coalgebraically.- Non-strongly Stable Orders Also Define Interesting Simulation Relations.- Stone Duality.- Stone Duality and the Recognisable Languages over an Algebra.- Free Heyting Algebras: Revisited.- Distributive Lattice-Structured Ontologies.- A Duality Theorem for Real C * Algebras.- Game Theory.- Conway Games, Coalgebraically.- A Semantical Approach to Equilibria and Rationality.- Graph Transformation.- Van Kampen Colimits as Bicolimits in Span.- Unfolding Grammars in Adhesive Categories.- Software Development Techniques.- Views on Behaviour Protocols and Their Semantic Foundation.- Correctness, Completeness and Termination of Pattern-Based Model-to-Model Transformation.- Constructor-Based Institutions.- CALCO Tools Workshop.- DBtk: A Toolkit for Directed Bigraphs.- Constraint-Muse: A Soft-Constraint Based System for Music Therapy.- CIRC: A Behavioral Verification Tool Based on Circular Coinduction.- ThePriced-Timed Maude Tool.- A Tool Proving Well-Definedness of Streams Using Termination Tools.