Results 1  10
of
41
A Structure Preserving Encoding of Z in Isabelle/HOL
 Theorem Proving in HigherOrder Logics, LNCS 1125
, 1996
"... . We present a semantic representation of the core concepts of the specification language Z in higherorder logic. Although it is a "shallow embedding" like the one presented by Bowen and Gordon, our representation preserves the structure of a Z specification and avoids expanding Z sch ..."
Abstract

Cited by 35 (7 self)
 Add to MetaCart
. We present a semantic representation of the core concepts of the specification language Z in higherorder logic. Although it is a "shallow embedding" like the one presented by Bowen and Gordon, our representation preserves the structure of a Z specification and avoids expanding Z schemas. The representation is implemented in the higherorder logic instance of the generic theorem prover Isabelle. Its parser can convert the concrete syntax of Z schemas into their semantic representation and thus spare users from having to deal with the representation explicitly. Our representation essentially conforms with the latest draft of the Z standard and may give both a clearer understanding of Z schemas and inspire the development of proof calculi for Z. 1 Introduction Implementations of proof support for Z [Spi 92, Nic 95] can roughly be divided into two categories. In direct implementations, the rules of the logic are directly represented by functions of the prover's implementation...
A Logic for ObjectZ
 PROCEEDINGS OF THE 9TH ANNUAL ZUSER MEETING
, 1994
"... This paper presents a logic for ObjectZ which extends W , the logic for Z adopted as the basis of the deductive system in the Z Base Standard. The logic provides a basis on which tool support for reasoning about ObjectZ specifications can be developed. It also formalises the intended meaning of ..."
Abstract

Cited by 29 (8 self)
 Add to MetaCart
This paper presents a logic for ObjectZ which extends W , the logic for Z adopted as the basis of the deductive system in the Z Base Standard. The logic provides a basis on which tool support for reasoning about ObjectZ specifications can be developed. It also formalises the intended meaning of ObjectZ constructs and hence provides an abstract, axiomatic semantics of the language.
Refinement and verification of concurrent systems specified in ObjectZ and CSP
 First International Conference on Formal Engineering Methods (ICFEM ’97
, 1997
"... The formal development of large or complex systems can often be facilitated by the use of more then one formal specification language. Such a combination of languages is particularly suited to the specification of concurrent or distributed systems, where both the modelling of processes and state is ..."
Abstract

Cited by 20 (7 self)
 Add to MetaCart
The formal development of large or complex systems can often be facilitated by the use of more then one formal specification language. Such a combination of languages is particularly suited to the specification of concurrent or distributed systems, where both the modelling of processes and state is necessary. This paper presents an approach to refinement and verification of specifications written using a combination of ObjectZ and CSP. A common semantic basis for the two languages enables a unified method of refinement to be used, based upon CSP refinement. To enable statebased techniques to be used for the ObjectZ components of a specification we develop statebased refinement relations which are sound and complete with respect to CSP refinement. In addition, a verification method for static and dynamic properties is presented. The method allows us to verify properties of the CSP system specification in terms of its component ObjectZ classes by using the laws of the CSP operators ...
Investigating Z
, 2000
"... In this paper we introduce and investigate an improved kernel logic ZC for the specification language Z. Unlike the standard accounts, this logic is consistent and is easily shown to be sound. We show how a complete schema calculus can be derived within this logic and in doing so we reveal a high de ..."
Abstract

Cited by 13 (6 self)
 Add to MetaCart
In this paper we introduce and investigate an improved kernel logic ZC for the specification language Z. Unlike the standard accounts, this logic is consistent and is easily shown to be sound. We show how a complete schema calculus can be derived within this logic and in doing so we reveal a high degree of logical organisation within the language. Finally, our approach eschews all nonstandard concepts introduced in the standard approach, notably object level notions of substitution and entities which share properties both of constants and variables. We show, in addition, that these unusual notions are derivable in ZC and are, therefore, unnecessary innovations. Keywords: Specification language Z; Logic and semantics of specification languages. 1 Introduction In this paper we introduce and investigate an improved kernel logic ZC for the specification language Z, a logic in which, in particular, we can derive a schema calculus: a logic for the entire range of schema expressions permit...
Reasoning about ObjectZ specifications
 IN ASIAPACIFIC SOFTWARE ENGINEERING CONFERENCE (APSEC95
, 1995
"... This paper presents a method of reasoning about ObjectZ specifications. The approach utilises the modularity inherent in ObjectZ specifications to simplify proofs. Properties proved for a class in isolation can be used when that class is either inherited by another class or instantiated as part ..."
Abstract

Cited by 11 (2 self)
 Add to MetaCart
(Show Context)
This paper presents a method of reasoning about ObjectZ specifications. The approach utilises the modularity inherent in ObjectZ specifications to simplify proofs. Properties proved for a class in isolation can be used when that class is either inherited by another class or instantiated as part of a system of interacting objects. Proofs using structural induction and the notion of object integrity are discussed.
An Analysis of Total Correctness Refinement Models for Partial Relation Semantics II
, 2000
"... This is the second in a series of papers devoted to the thorough investigation of (total correctness) refinement based on an underlying partial relational model. This paper investigates operation refinement and datarefinement based on a weakest precondition interpretation for specifications whose s ..."
Abstract

Cited by 9 (7 self)
 Add to MetaCart
This is the second in a series of papers devoted to the thorough investigation of (total correctness) refinement based on an underlying partial relational model. This paper investigates operation refinement and datarefinement based on a weakest precondition interpretation for specifications whose semantics is given by partial relations. We consider three refinement theories based on a weakest precondition interpretation for partial relation semantics: an operation refinement theory, and theories characterising datarefinement with forward and backward simulations. We show that each of these is equivalent to a (corresponding) modeltheoretic refinement theory that is based on the standard approach involving relational completion operators. In addition, we demonstrate that each of the three is also equivalent to a (corresponding) prooftheoretic notion of refinement.
Compositional Verification for ObjectZ
 In
, 2003
"... This paper presents a framework for compositional verification of ObjectZ specifications. Its key feature is a proof rule based on decomposition of hierarchical ObjectZ models. For each component in the hierarchy local properties are proven in a single proof step. However, we do not consider c ..."
Abstract

Cited by 8 (3 self)
 Add to MetaCart
(Show Context)
This paper presents a framework for compositional verification of ObjectZ specifications. Its key feature is a proof rule based on decomposition of hierarchical ObjectZ models. For each component in the hierarchy local properties are proven in a single proof step. However, we do not consider components in isolation. Instead, components are envisaged in the context of the referencing supercomponent and proof steps involve assumptions on properties of the subcomponents.
W Reconstructed
"... An early version of the Z Standard included the deductive system W for reasoning about Z specifications. Later versions contain a different deductive system. In this paper we sketch a proof that W is relatively sound with respect to this new deductive system. We do this by demonstrating a semantic b ..."
Abstract

Cited by 7 (2 self)
 Add to MetaCart
An early version of the Z Standard included the deductive system W for reasoning about Z specifications. Later versions contain a different deductive system. In this paper we sketch a proof that W is relatively sound with respect to this new deductive system. We do this by demonstrating a semantic basis for a correspondence between the two systems, then showing that each of the inference rules of W can be simulated as derived rules in the new system. These new rules are presented as tactics over the the inference rules of the new deductive system. 1 Introduction An important part of the Z Standardization activity has been the definition of a logical deductive system for Z. Whilst some have sought to provide support for reasoning about Z specifications by embedding the language in an existing wellunderstood framework (HOL, Eves, PVS, Isabelle, for example; [BG94,Jon92,Saa92,KSW96,ES94]), other research has attempted to provide support for reasoning within Z, making use of Z's type ...
A Formal Semantic Model of the Semantic Web Service Ontology (WSMO
 In The Twelfth IEEE International Conference on Engineering Complex Computer Systems (ICECCS’07
"... Semantic Web Services, one of the most significant research areas within the Semantic Web vision, has attracted increasing attention from both the research community and industry. The Web Service Modelling Ontology (WSMO) has recently been proposed as an enabling framework for the total/partial auto ..."
Abstract

Cited by 6 (2 self)
 Add to MetaCart
(Show Context)
Semantic Web Services, one of the most significant research areas within the Semantic Web vision, has attracted increasing attention from both the research community and industry. The Web Service Modelling Ontology (WSMO) has recently been proposed as an enabling framework for the total/partial automation of the tasks (e.g., discovery, selection, composition, mediation, execution, monitoring, etc.) involved in both intra and interenterprise integration of Web Services. To support the standardization and tool support of WSMO, a formal semantics of the language is highly desirable. As there are a few variants of WSMO and it is still under development, the semantics of WSMO needs to be formally defined to facilitate easy reuse and future development. In this paper, we present a formal ObjectZ semantics of WSMO. Different aspects of the language have been precisely defined within one unified framework. This model not only provides a formal unambiguous model which can be used to develop tools and facilitate future development, but as demonstrated in this paper, can be used to identify and eliminate errors presented in existing documentation. 1
A Formal OO Method Inspired by Fusion and ObjectZ
"... . We present a new formal OO method, called FOX , which is a synergetic combination of the semiformal Fusion method and the formal specification language ObjectZ. To manage complexity and to foster separation of concerns, FOX distinguishes between analysis and design. In each phase structu ..."
Abstract

Cited by 6 (0 self)
 Add to MetaCart
(Show Context)
. We present a new formal OO method, called FOX , which is a synergetic combination of the semiformal Fusion method and the formal specification language ObjectZ. To manage complexity and to foster separation of concerns, FOX distinguishes between analysis and design. In each phase structure and behaviour specifications are developed stepbystep. The specifications may be graphical or textual. We give proof obligations to guarantee that the developed models are formally consistent and complete, and that the resulting system conforms to the original specification. By walking through a simple example  a graph editor  we illustrate the application of FOX . 1 The Need for a Formal OO Method Semiformal OOA/D methods, such as Booch's objectoriented design [1] or Rumbaugh's OMT [20], are widely accepted in practice. Generally, they have a planned procedure; that is, stepbystep the software developer can approach a specific goal. This fact, combined with the support...