Results 1  10
of
44
Universal coalgebra: a theory of systems
, 2000
"... In the semantics of programming, nite data types such as finite lists, have traditionally been modelled by initial algebras. Later final coalgebras were used in order to deal with in finite data types. Coalgebras, which are the dual of algebras, turned out to be suited, moreover, as models for certa ..."
Abstract

Cited by 404 (43 self)
 Add to MetaCart
In the semantics of programming, nite data types such as finite lists, have traditionally been modelled by initial algebras. Later final coalgebras were used in order to deal with in finite data types. Coalgebras, which are the dual of algebras, turned out to be suited, moreover, as models for certain types of automata and more generally, for (transition and dynamical) systems. An important property of initial algebras is that they satisfy the familiar principle of induction. Such a principle was missing for coalgebras until the work of Aczel (NonWellFounded sets, CSLI Leethre Notes, Vol. 14, center for the study of Languages and information, Stanford, 1988) on a theory of nonwellfounded sets, in which he introduced a proof principle nowadays called coinduction. It was formulated in terms of bisimulation, a notion originally stemming from the world of concurrent programming languages. Using the notion of coalgebra homomorphism, the definition of bisimulation on coalgebras can be shown to be formally dual to that of congruence on algebras. Thus, the three basic notions of universal algebra: algebra, homomorphism of algebras, and congruence, turn out to correspond to coalgebra, homomorphism of coalgebras, and bisimulation, respectively. In this paper, the latter are taken
Ntyft/ntyxt rules reduce to ntree rules
 Information and Computation
, 1996
"... Groote and Vaandrager introduced the tyft/tyxt format for Transition System Specifications (TSSs), and established that for each TSS in this format that is wellfounded, the bisimulation equivalence it induces is a congruence. In this paper, we construct for each TSS in tyft/tyxt format an equivalen ..."
Abstract

Cited by 58 (18 self)
 Add to MetaCart
(Show Context)
Groote and Vaandrager introduced the tyft/tyxt format for Transition System Specifications (TSSs), and established that for each TSS in this format that is wellfounded, the bisimulation equivalence it induces is a congruence. In this paper, we construct for each TSS in tyft/tyxt format an equivalent TSS that consists of tree rules only. As a corollary we can give an affirmative answer to an open question, namely whether the wellfoundedness condition in the congruence theorem for tyft/tyxt can be dropped. These results extend to tyft/tyxt with negative premises and predicates. 1
A Conservative Look at Operational Semantics with Variable Binding
 INFORMATION AND COMPUTATION
, 1998
"... We set up a formal framework to describe transition system specifications in the style of Plotkin. This framework has the power to express manysortedness, general binding mechanisms and substitutions, among other notions such as negative hypotheses and unary predicates on terms. The framework i ..."
Abstract

Cited by 33 (4 self)
 Add to MetaCart
We set up a formal framework to describe transition system specifications in the style of Plotkin. This framework has the power to express manysortedness, general binding mechanisms and substitutions, among other notions such as negative hypotheses and unary predicates on terms. The framework is used to present a conservativity format in operational semantics, which states sufficient criteria to ensure that the extension of a transition system specification with new transition rules does not affect the semantics of the original terms.
Action Refinement
 Handbook of Proacess Algebra
, 2000
"... S. All local authors can be reached via email at the address lastname@cs.unibo.it. Questions and comments should be addressed to tradmin@cs.unibo.it. Recent Titles from the UBLCS Technical Report Series 974 An Algebra of Actors, M. Gaspari, G. Zavattaro, May 1997. 975 On the Turing Equivalen ..."
Abstract

Cited by 29 (4 self)
 Add to MetaCart
S. All local authors can be reached via email at the address lastname@cs.unibo.it. Questions and comments should be addressed to tradmin@cs.unibo.it. Recent Titles from the UBLCS Technical Report Series 974 An Algebra of Actors, M. Gaspari, G. Zavattaro, May 1997. 975 On the Turing Equivalence of Linda Coordination Primitives, N. Busi, R. Gorrieri, G. Zavattaro, May 1997 (Revised October 1998). 976 A Process Algebraic View of Linda Coordination Primitives, N. Busi, R. Gorrieri, G. Zavattaro, May 1997. 977 Validating a Software Architecture with respect to an Architectural Style, P. Ciancarini, W. Penzo, July 1997. 978 System Support for PartitionAware Network Applications, O. Babaoglu, R. Davoli, A. Montresor, R. Segala, October 1997. 979 Generalized SemiMarkovian Process Algebra, M. Bravetti, M. Bernardo, R. Gorrieri, October 1997. 981 Group Communication in Partitionable Systems: Specification and Algorithms, O. Babao glu, R. Davoli, A. Montresor, April 1998. 982...
Rooted branching bisimulation as a congruence
 Journal of Computer and System Sciences
, 2000
"... This article presents a congruence format, in structural operational semantics, for rooted branching bisimulation equivalence. The format imposes additional requirements on Groote’s ntyft format. It extends an earlier format by Bloom with standard notions such as recursion, iteration, predicates, an ..."
Abstract

Cited by 17 (6 self)
 Add to MetaCart
(Show Context)
This article presents a congruence format, in structural operational semantics, for rooted branching bisimulation equivalence. The format imposes additional requirements on Groote’s ntyft format. It extends an earlier format by Bloom with standard notions such as recursion, iteration, predicates, and negative premises. 1
SOS formats and metatheory: 20 years after
, 2007
"... In 1981 Structural Operational Semantics (SOS) was introduced as a systematic way to define operational semantics of programming languages by a set of rules of a certain shape [G.D. Plotkin, A structural approach to operational semantics, Technical ..."
Abstract

Cited by 14 (5 self)
 Add to MetaCart
(Show Context)
In 1981 Structural Operational Semantics (SOS) was introduced as a systematic way to define operational semantics of programming languages by a set of rules of a certain shape [G.D. Plotkin, A structural approach to operational semantics, Technical
A conservative look at term deduction systems with variable binding
, 1995
"... We set up a formal framework to describe term deduction systems, such as transition system speci cations in the style of Plotkin, and conditional term rewriting systems. This framework has the power to express manysortedness, general binding mechanisms and substitutions, among other notions such as ..."
Abstract

Cited by 11 (5 self)
 Add to MetaCart
(Show Context)
We set up a formal framework to describe term deduction systems, such as transition system speci cations in the style of Plotkin, and conditional term rewriting systems. This framework has the power to express manysortedness, general binding mechanisms and substitutions, among other notions such as negative premises and unary predicates on terms. The framework is used to present a conservativity format in operational semantics, which states sufficient criteria to ensure that the extension of a transition system specification with new rules does not affect the behaviour of the original terms. Furthermore, we showhowgeneral theorems in structured operational semantics can be transformed into results in conditional term rewriting. We apply this approach to the conservativity theorem, which yields a result that is useful in the field of abstract data types.
Conservative extension in positive/negative conditional term rewriting with applications to software renovation factories
 Proceedings 2nd Conference on Fundamental Approaches to Software Engineering
"... Abstract. We transpose a conservative extension theorem from structured operational semantics to conditional term rewriting. The result is useful for the development of software renovation factories, and for modular speci cation of abstract data types. 1 ..."
Abstract

Cited by 10 (5 self)
 Add to MetaCart
(Show Context)
Abstract. We transpose a conservative extension theorem from structured operational semantics to conditional term rewriting. The result is useful for the development of software renovation factories, and for modular speci cation of abstract data types. 1