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Specifying and Executing Behavioral Requirements: The PlayIn/PlayOut Approach
 Software and System Modeling (SoSyM
, 2002
"... A powerful methodology for scenariobased specification of reactive systems is described, in which the behavior is "played in" directly from the system's GUI or some abstract version thereof, and can then be "played out". The approach is supported and illustrated by a tool, which we call the playen ..."
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Cited by 56 (19 self)
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A powerful methodology for scenariobased specification of reactive systems is described, in which the behavior is "played in" directly from the system's GUI or some abstract version thereof, and can then be "played out". The approach is supported and illustrated by a tool, which we call the playengine. As the behavior is played in, the playengine automatically generates a formal version in an extended version of the language of live sequence charts (LSCs). As they are played out, it causes the application to react according to the universal ("must") parts of the specification; the existential ("may") parts can be monitored to check their successful completion. Playin is a userfriendly highlevel way of specifying behavior and playout is a rather surprising way of working with a fully operational system directly from its interobject requirements. The ideas appear to be relevant to many stages of system development, including requirements engineering, specification, testing, analysis and implementation.
Natural Deduction as HigherOrder Resolution
 Journal of Logic Programming
, 1986
"... An interactive theorem prover, Isabelle, is under development. In LCF, each inference rule is represented by one function for forwards proof and another (a tactic) for backwards proof. In Isabelle, each inference rule is represented by a Horn clause. ..."
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Cited by 54 (8 self)
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An interactive theorem prover, Isabelle, is under development. In LCF, each inference rule is represented by one function for forwards proof and another (a tactic) for backwards proof. In Isabelle, each inference rule is represented by a Horn clause.
GentzenType Systems, Resolution And Tableaux
 Journal of Automated Reasoning
, 1993
"... Introduction In advanced books and courses on logic (e.g. [Sm], [BM]) Gentzentype systems or their dual, tableaux, are described as techniques for showing validity of formulae which are more practical than the usual Hilberttype formalisms. People who have learnt these methods often wonder why the ..."
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Cited by 32 (12 self)
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Introduction In advanced books and courses on logic (e.g. [Sm], [BM]) Gentzentype systems or their dual, tableaux, are described as techniques for showing validity of formulae which are more practical than the usual Hilberttype formalisms. People who have learnt these methods often wonder why the Automated Reasoning community seems to ignore them and prefers instead the resolution method. Some of the classical books on AD (such as [CL], [Lo]) do not mention these methods at all. Others (such as [Ro]) do, but the connections and reasons for preference remain unclear after reading them (at least to the present author, and obviously also the authors of [OS], in which a theoremprover, based exclusively on tableaux, is described). The confusion becomes greater when the reader is introduced to Kowalski's form of a clause ([Ko], [Bu]), which is nothing but a Gentzen's sequent of atomic formulae, and when he realizes that resolution is just a form of a Cut, and so that while the<F1
A Verified Prolog Compiler for the Warren Abstract Machine
 Journal of Logic Programming
, 1992
"... Machine David M. Russinoff Microelectronics and Computer Technology Corporation 3500 West Balcones Center Drive Austin, TX 78759 (512) 3383583 Abstract We extend the theory of Prolog to provide a framework for the study of Prolog compilation technology. For this purpose, we first demonstrate ..."
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Cited by 18 (0 self)
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Machine David M. Russinoff Microelectronics and Computer Technology Corporation 3500 West Balcones Center Drive Austin, TX 78759 (512) 3383583 Abstract We extend the theory of Prolog to provide a framework for the study of Prolog compilation technology. For this purpose, we first demonstrate the semantic equivalence of two Prolog interpreters: a conventional SLDrefutation procedure and one that employs Warren's "last call" optimization. Next, we formally define the Warren Abstract Machine (WAM) and its instruction set and present a Prolog compiler for the WAM. Finally, we prove that the WAM execution of a compiled Prolog program produces the same result as the interpretation of its source. Contents 1 Introduction 1 2 Prolog 4 2.1 Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2 Semantics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 Last Call Optimization . . . . . . . . . . . . . . . . . . . . . . 10 3 The WAM 15 3.1 WAM States . ...
Transformation Rules For GHC Programs
 New Generation Computing
, 1988
"... Transformation rules for (Flat) GHC programs are presented, which refine the previous rules proposed by one of the authors (Furukawa et al. 1987). The rules are based on unfolding/folding and are novel in that they are stated in terms of idempotent substitutions with preferred directions of bindings ..."
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Cited by 12 (6 self)
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Transformation rules for (Flat) GHC programs are presented, which refine the previous rules proposed by one of the authors (Furukawa et al. 1987). The rules are based on unfolding/folding and are novel in that they are stated in terms of idempotent substitutions with preferred directions of bindings. They are more general than the old rules in that no mode system is assumed and that the rule of folding is included. The presentation of the rules suggests that idempotent substitutions with preferred directions of bindings are an appropriate tool for modeling information in (concurrent) logic programming. A semantic model is given which associates a multiset of goals with the set of possible finite sequences of transactions (via substitutions) with the multiset. A transformation preserves the set of transaction sequences that are made without the risk of the failure of unification. The model also deals with anomalous behavior such as the failure of unification and deadlock, so it can be s...
Deriving Database Queries from Logical Forms by Abductive Definition Expansion
, 1992
"... The paper describes a principled approach to the problem of deriving database queries from logical forms produced by a general NL interface. Our method attempts to construct a database query and a set of plausible assumptions, such that the logical form is equivalent to the query given the assumptio ..."
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Cited by 12 (3 self)
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The paper describes a principled approach to the problem of deriving database queries from logical forms produced by a general NL interface. Our method attempts to construct a database query and a set of plausible assumptions, such that the logical form is equivalent to the query given the assumptions. The domain information needed is provided as declarative meaning postulates, including "defini tional equivalences". The technical basis for the approach is that a "definition" of the form Head A Conditions  Body can be read procedurally as "Expand Head to Body if it oc curs in an environment where Conditions can be inferred". The "environment" is provided by the other conjuncts occurring together with Head in the original logical form, together with other meaning postulates and the contents of the database. The method has been implemented in CLARE, a language and reasoning system whose linguistic component is the SRI Core Language Engine.
First Order Linear Logic in Symmetric Monoidal Closed Categories
, 1991
"... There has recently been considerable interest in the development of `logical frameworks ' which can represent many of the logics arising in computer science in a uniform way. Within the Edinburgh LF project, this concept is split into two components; the first being a general proof theoretic encodin ..."
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Cited by 11 (0 self)
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There has recently been considerable interest in the development of `logical frameworks ' which can represent many of the logics arising in computer science in a uniform way. Within the Edinburgh LF project, this concept is split into two components; the first being a general proof theoretic encoding of logics, and the second a uniform treatment of their model theory. This thesis forms a case study for the work on model theory. The models of many first and higher order logics can be represented as fibred or indexed categories with certain extra structure, and this has been suggested as a general paradigm. The aim of the thesis is to test the strength and flexibility of this paradigm by studying the specific case of Girard's linear logic. It should be noted that the exact form of this logic in the first order case is not entirely certain, and the system treated here is significantly different to that considered by Girard.
Integrating Heterogenous OO Schemas
 Journal of Information Science and Engineering
, 2000
"... A key problem in providing enterprisewide information is the integration of databases that have been independently developed. A major requirement is to accommodate heterogeneity and at the same time preserve the autonomy of component databases. This article addresses this problem and presents a str ..."
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Cited by 2 (0 self)
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A key problem in providing enterprisewide information is the integration of databases that have been independently developed. A major requirement is to accommodate heterogeneity and at the same time preserve the autonomy of component databases. This article addresses this problem and presents a strategy to integrate heterogeneous OO schemas. As compared to the existing methodologies, this approach integrates local schemas into a deductionlike global schema. In this way, more semantic relationships of component schemas can be captured, and more complete integration can be obtained. In addition, an efficient algorithm is proposed which can do the integration almost automatically, based on the correspondence assertions supplied by designers. This algorithm is efficient in the sense that the characteristics of assertions are utilized to avoid useless matchings.
Automatically Reformulating SatEncoded CSPs
"... We examine two encodings of binary constraint satisfaction problems (CSPs) into propositional satisfiability (SAT). We show that hyperresolution rules can be used to infer, from the direct encoding, many of the clauses in the betterperforming support encoding. Our experimental results confirm that ..."
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Cited by 2 (0 self)
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We examine two encodings of binary constraint satisfaction problems (CSPs) into propositional satisfiability (SAT). We show that hyperresolution rules can be used to infer, from the direct encoding, many of the clauses in the betterperforming support encoding. Our experimental results confirm that applying hyperresolution in this way reduces both the runtime and the number of search nodes used by a SAT solver on the encoded CSPs.
Agents in Logic Programming
, 1997
"... The objective of this thesis is to explore ways of describing agents in logical theories. The contribution is that the logical theories we build are a generalised form of logic programs. Like normal logic programs, these theories have an intuitive declarative reading and a procedural interpretation ..."
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The objective of this thesis is to explore ways of describing agents in logical theories. The contribution is that the logical theories we build are a generalised form of logic programs. Like normal logic programs, these theories have an intuitive declarative reading and a procedural interpretation to guide the implementation of automatic devices and software. Both human beings and machines can reason about these logical theories. We employ the amalgamation of object and metalogic programs to model notions such as beliefs, goals and agent's "mental" activities. But we also accommodate less usual notions such as reactivity, openness, activation of goals and preference encoding, that have proved to be essential in realistic models of agents. Four logic programming languages to program agent with those features are introduced. We use an eventbased approach to model dynamic universes with changing properties, concurrency and synergistic effects. NOTE: This is a copy of the thesis with si...