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Temporal Development Methods for Agent-Based Systems
- J. Autonomous Agents and Multi-Agent Systems
"... Abstract. In this paper we overview one specific approach to the formal development of multi-agent systems. This approach is based on the use of temporal logics to represent both the behaviour of individual agents, and the macro-level behaviour of multi-agent systems. We describe how formal specific ..."
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Cited by 33 (5 self)
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Abstract. In this paper we overview one specific approach to the formal development of multi-agent systems. This approach is based on the use of temporal logics to represent both the behaviour of individual agents, and the macro-level behaviour of multi-agent systems. We describe how formal specification, verification and refinement can all be developed using this temporal basis, and how implementation can be achieved by directly executing these formal representations. We also show how the basic framework can be extended in various ways to handle the representation and implementation of agents capable of more complex deliberation and reasoning.
Monodic temporal resolution
- ACM Transactions on Computational Logic
, 2003
"... Until recently, First-Order Temporal Logic (FOTL) has been only partially understood. While it is well known that the full logic has no finite axiomatisation, a more detailed analysis of fragments of the logic was not previously available. However, a breakthrough by Hodkinson et al., identifying a f ..."
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Cited by 31 (15 self)
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Until recently, First-Order Temporal Logic (FOTL) has been only partially understood. While it is well known that the full logic has no finite axiomatisation, a more detailed analysis of fragments of the logic was not previously available. However, a breakthrough by Hodkinson et al., identifying a finitely axiomatisable fragment, termed the monodic fragment, has led to improved understanding of FOTL. Yet, in order to utilise these theoretical advances, it is important to have appropriate proof techniques for this monodic fragment. In this paper, we modify and extend the clausal temporal resolution technique, originally developed for propositional temporal logics, to enable its use in such monodic fragments. We develop a specific normal form for monodic formulae in FOTL, and provide a complete resolution calculus for formulae in this form. Not only is this clausal resolution technique useful as a practical proof technique for certain monodic classes, but the use of this approach provides us with increased understanding of the monodic fragment. In particular, we here show how several features of monodic FOTL can be established as corollaries of the completeness result for the clausal temporal resolution method. These include definitions of new decidable monodic classes, simplification of existing monodic classes by reductions, and completeness of clausal temporal resolution in the case of
Towards First-Order Temporal Resolution
- In KI 2001, Proceedings
"... In this paper we show how to extend clausal temporal resolution to the ground eventuality fragment of monodic first-order temporal logic, which has recently been introduced by Hodkinson, Wolter and Zakharyaschev. While a finite Hilbert-like axiomatization of complete monodic first order temporal ..."
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Cited by 27 (13 self)
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In this paper we show how to extend clausal temporal resolution to the ground eventuality fragment of monodic first-order temporal logic, which has recently been introduced by Hodkinson, Wolter and Zakharyaschev. While a finite Hilbert-like axiomatization of complete monodic first order temporal logic was developed by Wolter and Zakharyaschev, we propose a temporal resolutionbased proof system which reduces the satisfiability problem for ground eventuality monodic first-order temporal formulae to the satisfiability problem for formulae of classical first-order logic.
Temporal Resolution using a Breadth-First Search Algorithm
, 1998
"... this paper we present a breadth-rst search style algorithm which enables practical implementation of the resolution method for temporal logics developed by Fisher [15]. Fisher's method has been shown correct [36], deals with the full range of past and futuretime temporal operators and has only ..."
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Cited by 27 (14 self)
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this paper we present a breadth-rst search style algorithm which enables practical implementation of the resolution method for temporal logics developed by Fisher [15]. Fisher's method has been shown correct [36], deals with the full range of past and futuretime temporal operators and has only one temporal resolution rule making it suitable for mechanisation. The resolution procedure is characterised by translation to a normal form, the application of a classical style resolution rule to derive contradictions that occur at the same point in time (termed step resolution), together with a new resolution rule, which derives contradictions over temporal sequences (termed temporal resolution). As it is the latter that is the most expensive part of the algorithm, involving search through graphs, as well as the most novel, it is on the application of the temporal resolution rule that we concentrate. We suggest a breadth-rst search approach to the application of the temporal resolution rule and through analysis of its operation and output, explain why it is an improvement on search mechanisms suggested previously [12]
Combining Spatial and Temporal Logics: Expressiveness Vs. Complexity
- JOURNAL OF ARTIFICIAL INTELLIGENCE RESEARCH
, 2004
"... In this paper, we construct and investigate a hierarchy of spatio-temporal formalisms that result from various combinations of propositional spatial and temporal logics such as the propositional temporal logic the spatial logics RCC-8, BRCC-8, S4 u and their fragments. The obtained results give ..."
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Cited by 25 (9 self)
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In this paper, we construct and investigate a hierarchy of spatio-temporal formalisms that result from various combinations of propositional spatial and temporal logics such as the propositional temporal logic the spatial logics RCC-8, BRCC-8, S4 u and their fragments. The obtained results give a clear picture of the trade-off between expressiveness and `computational realisability' within the hierarchy. We demonstrate how di#erent combining principles as well as spatial and temporal primitives can produce NP-, PSPACE-, EXPSPACE-, 2EXPSPACE-complete, and even undecidable spatio-temporal logics out of components that are at most NP- or PSPACE-complete.
Search Strategies for Resolution in Temporal Logics
- Proceedings of the Thirteenth International Conference on Automated Deduction (CADE
, 1996
"... . In this paper we give and evaluate the algorithms for a fully automated temporal resolution theorem prover. An approach to applying resolution, a proof method for classical logics suited to mechanisation, to temporal logics has been developed by Fisher. As the application of the temporal resolutio ..."
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Cited by 25 (12 self)
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. In this paper we give and evaluate the algorithms for a fully automated temporal resolution theorem prover. An approach to applying resolution, a proof method for classical logics suited to mechanisation, to temporal logics has been developed by Fisher. As the application of the temporal resolution rule is the most costly part of the method, involving search amongst graphs, we propose different algorithms on which to base an implementation. The paper concludes with a comparison of their performance. 1 Introduction Temporal logics have been used extensively for the specification and verification of properties of concurrent systems, see for example [Hai82, Lam83, MP92]. However proof procedures for such logics have tended to be tableau [Wol85, Gou84] or automata [VW86] based rather than based on resolution [Rob65]. In many cases the resolution based decision procedures that have been developed for temporal logics [CdC84, Ven86, AM90] are unsuitable for implementation because they only...
TeMP: A Temporal Monodic Prover
- In Proc. IJCAR-04, LNAI
, 2004
"... We present TeMP---the first experimental system for testing validity of monodic temporal logic formulae. The prover implements fine-grained temporal resolution. The core operations required by the procedure are performed by an efficient resolution-based prover for classical first-order logic. ..."
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Cited by 21 (11 self)
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We present TeMP---the first experimental system for testing validity of monodic temporal logic formulae. The prover implements fine-grained temporal resolution. The core operations required by the procedure are performed by an efficient resolution-based prover for classical first-order logic.
Scientific benchmarking with temporal logic decision procedures
- In Proc. KR2002
, 2002
"... In this paper we propose a hypothesis-driven design of the empirical analysis of different decision procedures which we refer to as scientific benchmarking. The approach is to start by choosing the benchmark problems for which, on the basis of analytical considerations, we expect a particular decisi ..."
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Cited by 19 (9 self)
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In this paper we propose a hypothesis-driven design of the empirical analysis of different decision procedures which we refer to as scientific benchmarking. The approach is to start by choosing the benchmark problems for which, on the basis of analytical considerations, we expect a particular decision procedure to exhibit a behaviour different from another decision procedure. Then empirical tests are performed in order to verify the particular hypothesis concerning the decision procedures under consideration. As a case study, we apply this methodology to compare different decision procedures for propositional temporal logic. We define two classes of randomly generated temporal logic formulae which we use to investigate the behaviour of two tableaux-based temporal logic approaches using the Logics Workbench, a third tableaux-based approach using the STeP system, and temporal resolution using a new prover called TRP. 1
TRP++ 2.0: A temporal resolution prover
- In Proc. CADE-19, LNAI
, 2003
"... Temporal logics are extensions of classical logic with operators that deal with time. They have been used in a wide variety of areas within Computer Science and Artificial Intelligence, for example robotics [14], databases [15], hardware verification [8] and agent-based systems [12]. ..."
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Cited by 19 (8 self)
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Temporal logics are extensions of classical logic with operators that deal with time. They have been used in a wide variety of areas within Computer Science and Artificial Intelligence, for example robotics [14], databases [15], hardware verification [8] and agent-based systems [12].
Tractable Temporal Reasoning
- In Proc. International Joint Conference on Artificial Intelligence (IJCAI
, 2007
"... Temporal reasoning is widely used within both Computer Science and A.I. However, the underlying complexity of temporal proof in discrete temporal logics has led to the use of simplified formalisms and techniques, such as temporal interval algebras or model checking. In this paper we show that tracta ..."
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Cited by 17 (8 self)
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Temporal reasoning is widely used within both Computer Science and A.I. However, the underlying complexity of temporal proof in discrete temporal logics has led to the use of simplified formalisms and techniques, such as temporal interval algebras or model checking. In this paper we show that tractable sub-classes of propositional linear temporal logic can be developed, based on the use of XOR fragments of the logic. We not only show that such fragments can be decided, tractably, via clausal temporal resolution, but also show the benefits of combining multiple XOR fragments. For such combinations we establish completeness and complexity (of the resolution method), and also describe how such a temporal language might be used in application areas, for example the verification of multi-agent systems. This new approach to temporal reasoning provides a framework in which tractable temporal logics can be engineered by intelligently combining appropriate XOR fragments. 1
