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607
Concurrent Dynamic Epistemic Logic
, 2003
"... When giving an nalysis of knowledge in multiagent systems, one needs a framework in which higherorder information and its dynamics can both be represented. A recent tradition stoxting in origina work by Plaza treats all of knowledge, higherorder knowledge, and its dynamics on the sae foot. Our ..."
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Cited by 181 (31 self)
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When giving an nalysis of knowledge in multiagent systems, one needs a framework in which higherorder information and its dynamics can both be represented. A recent tradition stoxting in origina work by Plaza treats all of knowledge, higherorder knowledge, and its dynamics on the sae foot. Our work is in that tradition. It also fits in approaches that not only dynaize the epistemics, but also epistemize the dynamics: the ac tions that (groups of) agents perform oxe epistemic actions. Different agents may have different information about which action is taking place, including higherorder information. We demonstrate that such information changes require subtle descriptions. Our contribution is to provide a complete axiomatization for n action language of vn Ditmoxsch, where an action is interpreted as a relation between epistemic states (pointed models) and sets of epistemic states. The applicability of the framework is found in every context where multiagent strategic decision making is at stake, and aready demonstrated in gaelike scenoxios such as Cluedo and coxd games.
Interpolation in Modal Logic
, 1999
"... The interpolation property and Robinson's consistency property are important tools for applying logic to software engineering. We provide a uniform technique for proving the Interpolation Property, using the notion of bisimulation. For modal logics, this leads to simple, easytocheck condit ..."
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Cited by 102 (8 self)
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The interpolation property and Robinson's consistency property are important tools for applying logic to software engineering. We provide a uniform technique for proving the Interpolation Property, using the notion of bisimulation. For modal logics, this leads to simple, easytocheck conditions on the logic which imply interpolation. We apply this result to fibering of modal logics and to modal logics of knowledge and belief.
Coalgebraic modal logic: Soundness, completeness and decidability of local consequence
 Theoret. Comput. Sci
, 2002
"... This paper studies finitary modal logics, interpreted over coalgebras for an endofunctor, and establishes soundness, completeness and decidability results. The logics are studied within the abstract framework of coalgebraic modal logic, which can be instantiated with arbitrary endofunctors on the ca ..."
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Cited by 74 (29 self)
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This paper studies finitary modal logics, interpreted over coalgebras for an endofunctor, and establishes soundness, completeness and decidability results. The logics are studied within the abstract framework of coalgebraic modal logic, which can be instantiated with arbitrary endofunctors on the category of sets. This is achieved through the use of predicate liftings, which generalise atomic propositions and modal operators from Kripke models to arbitrary coalgebras. Predicate liftings also allow us to use induction along the terminal sequence of the underlying endofunctor as a proof principle. This induction principle is systematically exploited to establish soundness, completeness and decidability of the logics. We believe that this induction principle also opens new ways for reasoning about modal logics: Our proof of completeness does not rely on a canonical model construction, and the proof of the finite model property does not use filtrations. 1
Hybrid Logics
"... This chapter provides a modern overview of the field of hybrid logic. Hybrid logics are extensions of standard modal logics, involving symbols that name individual states in models. The first results that are nowadays considered as part of the field date back to the early work of Arthur ..."
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Cited by 62 (18 self)
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This chapter provides a modern overview of the field of hybrid logic. Hybrid logics are extensions of standard modal logics, involving symbols that name individual states in models. The first results that are nowadays considered as part of the field date back to the early work of Arthur
Conditional XPath
 ACM Trans. Database Syst
, 2005
"... Abstract. XPath 1.0 is a variable free language designed to specify paths between nodes in XML documents. Such paths can alternatively be specified in firstorder logic. The logical abstraction of XPath 1.0, usually called Navigational or Core XPath, is not powerful enough to express every firstord ..."
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Cited by 62 (5 self)
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Abstract. XPath 1.0 is a variable free language designed to specify paths between nodes in XML documents. Such paths can alternatively be specified in firstorder logic. The logical abstraction of XPath 1.0, usually called Navigational or Core XPath, is not powerful enough to express every firstorder definable path. In this paper we show that there exists a natural expansion of Core XPath in which every firstorder definable path in XML document trees is expressible. This expansion is called Conditional XPath. It contains additional axis relations of the form (child::n[F])+, denoting the transitive closure of the path expressed by child::n[F]. The difference with XPath’s descendant::n[F] is that the path (child::n[F])+ is conditional on the fact that all nodes in between should be labeled by n and should make the predicate F true. This result can be viewed as the XPath analogue of the expressive completeness of the relational algebra with respect to firstorder logic. 1
On the Origins of Bisimulation and Coinduction
"... The origins of bisimulation and bisimilarity are examined, in the three fields where they have been ..."
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Cited by 61 (0 self)
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The origins of bisimulation and bisimilarity are examined, in the three fields where they have been
On The Logic Of Cooperation And Propositional Control
, 2005
"... Cooperation logics have recently begun to attract attention within the multiagent systems community. Using a cooperation logic, it is possible to represent and reason about the strategic powers of agents and coalitions of agents in gamelike multiagent systems. These powers are generally assumed t ..."
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Cited by 57 (22 self)
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Cooperation logics have recently begun to attract attention within the multiagent systems community. Using a cooperation logic, it is possible to represent and reason about the strategic powers of agents and coalitions of agents in gamelike multiagent systems. These powers are generally assumed to be implicitly defined within the structure of the environment, and their origin is rarely discussed. In this paper, we study a cooperation logic in which agents are each assumed to control a set of propositional variablesthe powers of agents and coalitions then derive from the allocation of propositions to agents. The basic modal constructs in this Coalition Logic of Propositional Control (CLPC) allow us to express the fact that a group of agents can cooperate to bring about a certain state of affairs. After motivating and introducing CLPC, we provide a complete axiom system for the logic, investigate the issue of characterising control in CLPC with respect to the underlying power structures of the logic, and formally investigate the relationship between CLPC and Pauly's Coalition Logic. We then show that the model checking and satisfiability problems for CLPC are both PSPACEcomplete, and conclude by discussing our results and how CLPC sits in relation to other logics of cooperation.
Talking About Trees
 In Proceedings of the 6th Conference of the European Chapter of the Association for Computational Linguistics
, 1993
"... In this paper we introduce a modal lan guage L T for imposing constraints on trees, and an extension LT(L r) for imposing con straints on trees decorated with feature structures. The motivation for introducing these languages is to provide tools for formalising grammatical frameworks perspic ..."
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Cited by 49 (3 self)
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In this paper we introduce a modal lan guage L T for imposing constraints on trees, and an extension LT(L r) for imposing con straints on trees decorated with feature structures. The motivation for introducing these languages is to provide tools for formalising grammatical frameworks perspicuously, and the paper illustrates this by showing how the leading ideas of arsa can be captured in LT(Lr).
Hierarchies of Modal and Temporal Logics with Reference Pointers
 Journal of Logic, Language and Information
, 1995
"... . We introduce and study hierarchies of extensions of the propositional modal and temporal languages with pairs of new syntactic devices: "point of reference  reference pointer" which enable semantic references to be made within a formula. We propose three different but equivalent sema ..."
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Cited by 46 (4 self)
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. We introduce and study hierarchies of extensions of the propositional modal and temporal languages with pairs of new syntactic devices: "point of reference  reference pointer" which enable semantic references to be made within a formula. We propose three different but equivalent semantics for the extended languages, discuss and compare their expressiveness. The languages with reference pointers are shown to have great expressive power (especially when their frugal syntax is taken into account), perspicuous semantics, and simple deductive systems. For instance, Kamp's and Stavi's temporal operators, as well as nominals (names, clock variables), are definable in them. The universal validity in these languages is proved undecidable. The basic modal and temporal logics with reference pointers are uniformly axiomatized and strong completeness theorem is proved for them and extended to some classes of their extensions. Key words: Modal and Temporal Logics, Reference Pointers, Expressi...