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41
Substructural Logics on Display
, 1998
"... Substructural logics are traditionally obtained by dropping some or all of the structural rules from Gentzen's sequent calculi LK or LJ. It is well known that the usual logical connectives then split into more than one connective. Alternatively, one can start with the (intuitionistic) Lambek calculu ..."
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Cited by 38 (16 self)
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Substructural logics are traditionally obtained by dropping some or all of the structural rules from Gentzen's sequent calculi LK or LJ. It is well known that the usual logical connectives then split into more than one connective. Alternatively, one can start with the (intuitionistic) Lambek calculus, which contains these multiple connectives, and obtain numerous logics like: exponentialfree linear logic, relevant logic, BCK logic, and intuitionistic logic, in an incremental way. Each of these logics also has a classical counterpart, and some also have a "cyclic" counterpart. These logics have been studied extensively and are quite well understood. Generalising further, one can start with intuitionistic BiLambek logic, which contains the dual of every connective from the Lambek calculus. The addition of the structural rules then gives Bilinear, Birelevant, BiBCK and Biintuitionistic logic, again in an incremental way. Each of these logics also has a classical counterpart, and som...
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 schemas. The ..."
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Cited by 34 (7 self)
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. 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...
The Refinement Calculator: Proof Support for Program Refinement
 Formal Methods Pacific ’97
, 1997
"... . We describe the Refinement Calculator, a tool which supports ..."
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Cited by 27 (2 self)
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. We describe the Refinement Calculator, a tool which supports
Cutfree Display Calculi for Relation Algebras
, 1997
"... . We extend Belnap's Display Logic to give a cutfree Gentzenstyle calculus for relation algebras. The calculus gives many axiomatic extensions of relation algebras by the addition of further structural rules. It also appears to be the first purely propositional Gentzenstyle calculus for relation ..."
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Cited by 21 (14 self)
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. We extend Belnap's Display Logic to give a cutfree Gentzenstyle calculus for relation algebras. The calculus gives many axiomatic extensions of relation algebras by the addition of further structural rules. It also appears to be the first purely propositional Gentzenstyle calculus for relation algebras. 1 Introduction Given a nonempty set U , the universal relation U \Theta U is the set of all ordered pairs (a; b) where a 2 U and b 2 U . Any subset of U \Theta U is a binary relation over U , and the set of all subsets of U \Theta U is the set of all binary relations over U . Thus any two binary relations R and S are each just a set of ordered pairs, and we can use the settheoretic operations of complement, intersection and union to build other relations. The identity relation is f(a; a) j a 2 Ug while the "relative" analogues of complement, intersection and union are converse (` R) = f(b; a) j (a; b) 2 Rg, composition (R ffi S) = f(a; b) j 9c; (a; c) 2 R and (c; b) 2 Sg and ...
Structured Calculational Proof
, 1996
"... We propose a new format for writing proofs, which we call structured calculational proof. The format is similar to the calculational style of proof already familiar to many computer scientists, but extends it by allowing large proofs to be hierarchically decomposed into smaller ones. In fact, struc ..."
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Cited by 16 (9 self)
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We propose a new format for writing proofs, which we call structured calculational proof. The format is similar to the calculational style of proof already familiar to many computer scientists, but extends it by allowing large proofs to be hierarchically decomposed into smaller ones. In fact, structured calculational proof can be seen as an alternative presentation of natural deduction. Natural deduction is a well established style of reasoning which uses hierarchical decomposition to great effect, but which is traditionally expressed in a notation that is inconvenient for writing calculational proofs. The hierarchical nature of structured calculational proofs can be used for proof browsing. We comment on how browsing can increase the value of a proof, and discuss the possibilities offered by electronic publishing for the presentation and dissemination of papers containing browsable proofs. Note: This paper is also available as Australian National University Joint Computer Science Tec...
A Tool for Developing Correct Programs By Refinement
 PROC. BCS 7TH REFINEMENT WORKSHOP
, 1996
"... The refinement calculus for the development of programs from specifications is well suited to mechanised support. We review the requirements for tool support of refinement as gleaned from our experience with a number of existing refinement tools, and report on the design and implementation of a ..."
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Cited by 13 (4 self)
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The refinement calculus for the development of programs from specifications is well suited to mechanised support. We review the requirements for tool support of refinement as gleaned from our experience with a number of existing refinement tools, and report on the design and implementation of a new tool to support refinement based on these requirements. The main features of the new tool are close integration of refinement and proof in a single tool (the same mechanism is used for both), good management of the refinement context, an extensible theory base that allows the tool to be adapted to new application domains, and a flexible user interface.
Ergo 4.1 Reference Manual
, 1996
"... This document describes the commands available in the theorem prover Ergo. It assumes that the reader is familiar, to some extent, with Ergo (refer to the Ergo User Manual [UW94]). As such, it is intended to serve as a reference only. Ergo is a term rewriting theorem prover designed and implemented ..."
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Cited by 11 (2 self)
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This document describes the commands available in the theorem prover Ergo. It assumes that the reader is familiar, to some extent, with Ergo (refer to the Ergo User Manual [UW94]). As such, it is intended to serve as a reference only. Ergo is a term rewriting theorem prover designed and implemented at the Software Verification Research Centre at the University of Queensland. It is based on the window inference [RS93, Gru92] proof paradigm. The architecture of Ergo is based on a layered design (Figure 1). The proof engine
Annotated Reasoning
 Annals of Mathematics and Artificial Intelligence (AMAI). Special Issue on Strategies in Automated Deduction
, 2000
"... Proof Search According to [12], abstract proof search is a process by which, starting from a representation of a problem at a socalled ground level, we construct a new and simpler representation at a socalled abstract level and use it to solve the original problem. That is, we abstract the given ..."
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Cited by 11 (4 self)
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Proof Search According to [12], abstract proof search is a process by which, starting from a representation of a problem at a socalled ground level, we construct a new and simpler representation at a socalled abstract level and use it to solve the original problem. That is, we abstract the given goal, prove its abstracted version and then use the information about the resulting abstract proof as an outline to construct the proof at the ground level. Dierent techniques to abstract from details have been studied in the literature. The problem is to nd out which details should be abstracted away. On one hand, if we abstract too much information then we often obtain abstract solutions that cannot be transferred to the ground level. Then, planning at the abstract level is even more dicult than planning at the ground level because the abstraction removes necessary control information, or we obtain only little information from the abstract proof how to guide the proof at the ground leve...
A Browsable Format for Proof Presentation
 Mathesis Universalis
, 1996
"... The paper describes a format for presenting proofs called structured calculational proof. The format resembles calculational proof, a style of reasoning popular among computer scientists, but extended with structuring facilities. A prototype tool has been developed which allows readers to interacti ..."
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Cited by 10 (2 self)
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The paper describes a format for presenting proofs called structured calculational proof. The format resembles calculational proof, a style of reasoning popular among computer scientists, but extended with structuring facilities. A prototype tool has been developed which allows readers to interactively browse proofs presented in this format via the world wide web. The ability to browse a proof increases its readability, and hence its value as a proof. Computers have been used for some time to both construct and check mathematical proofs, but using them to enhance the readability of proofs is a relatively novel application. This paper was originally presented at the symposium on Logic, Mathematics and the Computer The reference is as follows: Jim Grundy. A browsable format for proof presentation. In Christoffer Gefwert, Pekka Orponen and Jouko Seppanen (editors), Logic, Mathematics and the Computer  Foundations: History, Philosophy and Applications, volume 14 of the Finnish Artifi...
A Transformational Approach to Formal Digital System Design
, 1993
"... syntax for design annotations : : : : : : : : : : : : : : : : : 45 4.3 Semantic algebras for design annotations : : : : : : : : : : : : : : : : 46 4.4 Semantic algebras, continued : : : : : : : : : : : : : : : : : : : : : : : 47 4.5 Valuation functions for design annotations : : : : : : : : : : : : ..."
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Cited by 10 (0 self)
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syntax for design annotations : : : : : : : : : : : : : : : : : 45 4.3 Semantic algebras for design annotations : : : : : : : : : : : : : : : : 46 4.4 Semantic algebras, continued : : : : : : : : : : : : : : : : : : : : : : : 47 4.5 Valuation functions for design annotations : : : : : : : : : : : : : : : 48 4.6 Devices : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 50 5.1 Constant dummy in the basic library : : : : : : : : : : : : : : : : : : 58 5.2 Interconnection devices in the basic library : : : : : : : : : : : : : : : 58 5.3 Devices in the comp library : : : : : : : : : : : : : : : : : : : : : : : 59 5.4 Timing analysis of the design in session box 7 : : : : : : : : : : : : : 66 5.5 Scheduling the design in session box 7 : : : : : : : : : : : : : : : : : : 67 5.6 The design after session box 8 : : : : : : : : : : : : : : : : : : : : : : 68 5.7 The design after session box 15 : : : : : : : : : : : : : : : : : : : : : 74 5.8 The design after session box 16 : : :...