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246
First Order Data Types and First Order Logic
, 1991
"... : This paper concerns the relation between parameterized first order data types and first order logic. Augmenting first order logic by data type definitions yields in general a strictly stronger logic than first order logic. We consider some properties of the new logic for fixed data type definition ..."
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definitions. While our new logic always fulfills the downward SkolemLowenheim property, compactness is fulfilled if and only if for the given data type definition the new logic has the same expressive power than first order logic. We show that this last property is undecidable. Ralf Treinen, Fachbereich 14
Augmenting Concept Languages by Transitive Closure of Roles: An Alternative to Terminological Cycles
, 1990
"... In Baader (1990a,1990b), we have considered different types of semantics for terminologicial cycles in the concept language FL0 which allows only conjunction of concepts and value restrictions. It turned out that greatest fixedpoint semantics (gfpsemantics) seems to be most appropriate for cycles ..."
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Cited by 132 (24 self)
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In Baader (1990a,1990b), we have considered different types of semantics for terminologicial cycles in the concept language FL0 which allows only conjunction of concepts and value restrictions. It turned out that greatest fixedpoint semantics (gfpsemantics) seems to be most appropriate for cycles in this language. In the present paper we shall show that the concept defining facilities of FL0 with cyclic definitions and gfpsemantics can also be obtained in a different way. One may replace cycles by role definitions involving union, composition, and transitive closure of roles. This proposes a way of retaining, in an extended language, the pleasant features of gfpsemantics for FL0 with cyclic definitions without running into the troubles caused by cycles in larger languages. Starting with the language ALC of Schmidt Schauß
Records for Logic Programming
 Journal of Logic Programming
, 1994
"... CFT is a new constraint system providing records as logical data structure for constraint (logic) programming. It can be seen as a generalization of the rational tree system employed in Prolog II, where finergrained constraints are used, and where subtrees are identified by keywords rather than by ..."
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Cited by 101 (19 self)
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CFT is a new constraint system providing records as logical data structure for constraint (logic) programming. It can be seen as a generalization of the rational tree system employed in Prolog II, where finergrained constraints are used, and where subtrees are identified by keywords rather than by position. CFT is defined by a firstorder structure consisting of socalled feature trees. Feature trees generalize the ordinary trees corresponding to firstorder terms by having their edges labeled with field names called features. The mathematical semantics given by the feature tree structure is complemented with a logical semantics given by five axiom schemes, which we conjecture to comprise a complete axiomatization of the feature tree structure. We present a decision method for CFT, which decides entailment / disentailment between possibly existentially quantified constraints. Since CFT satisfies the independence property, our decision method can also be employed for checking the sat...
A survey of algebraic properties used in cryptographic protocols
 JOURNAL OF COMPUTER SECURITY
"... Cryptographic protocols are successfully analyzed using formal methods. However, formal approaches usually consider the encryption schemes as black boxes and assume that an adversary cannot learn anything from an encrypted message except if he has the key. Such an assumption is too strong in general ..."
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Cited by 69 (20 self)
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Cryptographic protocols are successfully analyzed using formal methods. However, formal approaches usually consider the encryption schemes as black boxes and assume that an adversary cannot learn anything from an encrypted message except if he has the key. Such an assumption is too strong in general since some attacks exploit in a clever way the interaction between protocol rules and properties of cryptographic operators. Moreover, the executability of some protocols relies explicitly on some algebraic properties of cryptographic primitives such as commutative encryption. We give a list of some relevant algebraic properties of cryptographic operators, and for each of them, we provide examples of protocols or attacks using these properties. We also give an overview of the existing methods in formal approaches for analyzing cryptographic proto
A Foundation for Higherorder Concurrent Constraint Programming
, 1994
"... We present the flcalculus, a computational calculus for higherorder concurrent programming. The calculus can elegantly express higherorder functions (both eager and lazy) and concurrent objects with encapsulated state and multiple inheritance. The primitives of the flcalculus are logic variables ..."
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Cited by 66 (13 self)
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We present the flcalculus, a computational calculus for higherorder concurrent programming. The calculus can elegantly express higherorder functions (both eager and lazy) and concurrent objects with encapsulated state and multiple inheritance. The primitives of the flcalculus are logic variables, names, procedural abstraction, and cells. Cells provide a notion of state that is fully compatible with concurrency and constraints. Although it does not have a dedicated communication primitive, the flcalculus can elegantly express onetomany and manytoone communication. There is an interesting relationship between the flcalculus and the ßcalculus: The flcalculus is subsumed by a calculus obtained by extending the asynchronous and polyadic ßcalculus with logic variables. The flcalculus can be extended with primitives providing for constraintbased problem solving in the style of logic programming. A such extended flcalculus has the remarkable property that it combines firstor...
Managing the Complexity of Large Free and Open Source PackageBased Software Distributions
 in &quot;Proceedings of the 21st IEEE/ACM International Conference on Automated Software Ingineering (ASE’06
, 2006
"... The widespread adoption of Free and Open Source Software (FOSS) in many strategic contexts of the information technology society has drawn the attention on the issues regarding how to handle the complexity of assembling and managing a huge number of (packaged) components in a consistent and effectiv ..."
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Cited by 53 (18 self)
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The widespread adoption of Free and Open Source Software (FOSS) in many strategic contexts of the information technology society has drawn the attention on the issues regarding how to handle the complexity of assembling and managing a huge number of (packaged) components in a consistent and effective way. FOSS distributions (and in particular GNU/Linuxbased ones) have always provided tools for managing the tasks of installing, removing and upgrading the (packaged) components they were made of. While these tools provide a (not always effective) way to handle these tasks on the client side, there is still a lack of tools that could help the distribution editors to maintain, on the server side, large and highquality distributions. In this paper we present our research whose main goal is to fill this gap: we show our approach, the tools we have developed and their application with experimental results. Our contribution provides an effective and automatic way to support distribution editors in handling those issues that were, until now, mostly addressed using adhoc tools and manual techniques. 1
Dominance Constraints: Algorithms and Complexity
 IN PROCEEDINGS OF THE THIRD CONFERENCE ON LOGICAL ASPECTS OF COMPUTATIONAL LINGUISTICS
, 1998
"... Dominance constraints for finite tree structures are widely used in several areas of computational linguistics including syntax, semantics, and discourse. In this paper, we investigate algorithmic and complexity questions for dominance constraints and their firstorder theory. We present two NP algo ..."
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Cited by 40 (21 self)
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Dominance constraints for finite tree structures are widely used in several areas of computational linguistics including syntax, semantics, and discourse. In this paper, we investigate algorithmic and complexity questions for dominance constraints and their firstorder theory. We present two NP algorithms for solving dominance constraints, which have been implemented in the concurrent constraint programming language Oz. The main result of this paper is that the satisfiability problem of dominance constraints is NPcomplete. Despite this intractability result, the more sophisticated of our algorithms performs well in an application to scope underspecification. We also show that the existential fragment of the firstorder theory of dominance constraints is NPcomplete and that the full firstorder theory has nonelementary complexity.
Programming Constraint Inference Engines
 Proceedings of the Third International Conference on Principles and Practice of Constraint Programming
, 1997
"... Existing constraint programming systems offer a fixed set of inference engines implementing search strategies such as single, all, and best solution search. This is unfortunate, since new engines cannot be integrated by the user. ..."
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Cited by 49 (6 self)
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Existing constraint programming systems offer a fixed set of inference engines implementing search strategies such as single, all, and best solution search. This is unfortunate, since new engines cannot be integrated by the user.
A New Method for Undecidability Proofs of First Order Theories
 Journal of Symbolic Computation
, 1992
"... this paper is to define a framework for such reduction proofs. The method proposed is illustrated by proving the undecidability of the theory of a term algebra modulo the axioms of associativity and commutativity and of the theory of a partial lexicographic path ordering. 1. Introduction ..."
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Cited by 30 (6 self)
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this paper is to define a framework for such reduction proofs. The method proposed is illustrated by proving the undecidability of the theory of a term algebra modulo the axioms of associativity and commutativity and of the theory of a partial lexicographic path ordering. 1. Introduction
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