Results 1  10
of
21
Monodic temporal resolution
 ACM Transactions on Computational Logic
, 2003
"... Until recently, FirstOrder 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 ..."
Abstract

Cited by 31 (15 self)
 Add to MetaCart
Until recently, FirstOrder 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
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 ..."
Abstract

Cited by 17 (8 self)
 Add to MetaCart
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 subclasses 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 multiagent 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
Reasoning support for expressive ontology languages using a theorem prover
 In FoIKS
, 2006
"... Abstract. It is claimed in [45] that firstorder theorem provers are not efficient for reasoning with ontologies based on description logics compared to specialised description logic reasoners. However, the development of more expressive ontology languages requires the use of theorem provers able to ..."
Abstract

Cited by 15 (0 self)
 Add to MetaCart
(Show Context)
Abstract. It is claimed in [45] that firstorder theorem provers are not efficient for reasoning with ontologies based on description logics compared to specialised description logic reasoners. However, the development of more expressive ontology languages requires the use of theorem provers able to reason with full firstorder logic and even its extensions. So far, theorem provers have extensively been used for running experiments over TPTP containing mainly problems with relatively small axiomatisations. A question arises whether such theorem provers can be used to reason in real time with large axiomatisations used in expressive ontologies such as SUMO. In this paper we answer this question affirmatively by showing that a carefully engineered theorem prover can answer queries to ontologies having over 15,000 firstorder axioms with equality. Ontologies used in our experiments are based on the language KIF, whose expressive power goes far beyond the description logic based languages currently used in the Semantic Web.
TRP ++ : A temporal resolution prover
 In Collegium Logicum
, 2002
"... this paper. 2 Basics of PLTL Let P be a set of propositional variables. The set of formulae of propositional linear time logic PLTL (over P) is inductively defined as follows: (i) ? is a formula of PLTL, (ii) every propositional variable of P is a formula of PLTL, (iii) if ' and / are formula ..."
Abstract

Cited by 12 (5 self)
 Add to MetaCart
(Show Context)
this paper. 2 Basics of PLTL Let P be a set of propositional variables. The set of formulae of propositional linear time logic PLTL (over P) is inductively defined as follows: (i) ? is a formula of PLTL, (ii) every propositional variable of P is a formula of PLTL, (iii) if ' and / are formulae of PLTL, then :' and (' /) are formulae of PLTL, and (iv) if ' and / are formulae of PLTL, then #' (in the next moment of time ' is true), 3' (sometimes in the future ' is true), 2' (always in the future ' is true), (' U /) (' is true until / is true), and (' W /) (' is true unless / is true) are formulae of PLTL. Other Boolean connectives including ?, , !, and $ are defined using ?, :, and
Is There a Future for Deductive Temporal Verification
 In Proc. TIME06. IEEE Computer
, 2006
"... complexity; clausal temporal resolution. In this paper, we consider a tractable subclass of propositional linear time temporal logic, and provide a complete clausal resolution calculus for it. The fragment is important as it captures simple Büchi automata. We also show that, just as the emptiness c ..."
Abstract

Cited by 10 (8 self)
 Add to MetaCart
(Show Context)
complexity; clausal temporal resolution. In this paper, we consider a tractable subclass of propositional linear time temporal logic, and provide a complete clausal resolution calculus for it. The fragment is important as it captures simple Büchi automata. We also show that, just as the emptiness check for a Büchi automaton is tractable, the complexity of deciding unsatisfiability, via resolution, of our logic is polynomial (rather than exponential). Consequently, a Büchi automaton can be represented within our logic, and its emptiness can be tractably decided via deductive methods. This may have a significant impact upon approaches to verification, since techniques such as model checking inherently depend on the ability to check emptiness of an appropriate Büchi automaton. Thus, we also discuss how such a logic might form the basis for practical deductive temporal verification. 1
Deciding monodic fragments by temporal resolution
 In Proc. CADE20
, 2005
"... Abstract. In this paper we study the decidability of various fragments of monodic firstorder temporal logic by temporal resolution. We focus on two resolution calculi, namely, monodic temporal resolution and finegrained temporal resolution. For the first, we state a very general decidability result ..."
Abstract

Cited by 4 (2 self)
 Add to MetaCart
(Show Context)
Abstract. In this paper we study the decidability of various fragments of monodic firstorder temporal logic by temporal resolution. We focus on two resolution calculi, namely, monodic temporal resolution and finegrained temporal resolution. For the first, we state a very general decidability result, which is independent of the particular decision procedure used to decide the firstorder part of the logic. For the second, we introduce refinements using orderings and selection functions. This allows us to transfer existing results on decidability by resolution for firstorder fragments to monodic firstorder temporal logic and obtain new decision procedures. The latter is of immediate practical value, due to the availability of TeMP, an implementation of finegrained temporal resolution. 1
Practical firstorder temporal reasoning
 Proceedings of 15th International Symposium on Temporal Representation and Reasoning (TIME), IEEE
, 2008
"... In this paper we consider the specification and verification of infinitestate systems using temporal logic. In particular, we describe parameterised systems using a new variety of firstorder temporal logic that is both powerful enough for this form of specification and tractable enough for practic ..."
Abstract

Cited by 3 (1 self)
 Add to MetaCart
(Show Context)
In this paper we consider the specification and verification of infinitestate systems using temporal logic. In particular, we describe parameterised systems using a new variety of firstorder temporal logic that is both powerful enough for this form of specification and tractable enough for practical deductive verification. Importantly, the power of the temporal language allows us to describe (and verify) asynchronous systems, communication delays and more complex liveness and fairness properties. These aspects appear difficult for many other approaches to infinitestate verification. 1.
Efficient FirstOrder Temporal Logic for InfiniteState Systems
, 2007
"... In this paper we consider the specification and verification of infinitestate systems using temporal logic. In particular, we describe parameterised systems using a new variety of firstorder temporal logic that is both powerful enough for this form of specification and tractable enough for practic ..."
Abstract

Cited by 2 (0 self)
 Add to MetaCart
(Show Context)
In this paper we consider the specification and verification of infinitestate systems using temporal logic. In particular, we describe parameterised systems using a new variety of firstorder temporal logic that is both powerful enough for this form of specification and tractable enough for practical deductive verification. Importantly, the power of the temporal language allows us to describe (and verify) asynchronous systems, communication delays and more complex properties such as liveness and fairness properties. These aspects appear difficult for many other approaches to infinitestate verification. 1
Temporal verification of faulttolerant protocols
 In Methods Models and Tools for Fault Tolerance
"... The automated verification of concurrent and distributed systems is a vibrant and successful area within Computer Science. Over the last 30 years, temporal logic [10, 20] has been shown to provide a clear, concise and intuitive description of many such systems, and automatatheoretic techniques such ..."
Abstract

Cited by 1 (1 self)
 Add to MetaCart
(Show Context)
The automated verification of concurrent and distributed systems is a vibrant and successful area within Computer Science. Over the last 30 years, temporal logic [10, 20] has been shown to provide a clear, concise and intuitive description of many such systems, and automatatheoretic techniques such as model checking [7, 14] have been
A Matrix Based Approach for Modeling Robotic Swarm Behavior
"... Abstract Swarm robotics systems can be categorized as discrete event systems (DES) and can therefore be subjected to DES modeling and analysis tools. Taking on the same approach and considering successful application of matrices to model complex DES like flexible manufacturing systems, we present h ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
(Show Context)
Abstract Swarm robotics systems can be categorized as discrete event systems (DES) and can therefore be subjected to DES modeling and analysis tools. Taking on the same approach and considering successful application of matrices to model complex DES like flexible manufacturing systems, we present here a novel matrix formulation to model emergent coherent movement of a wirelessly connected swarm of robots. In order to move the swarm in a desired direction, an external control input is defined that changes the direction of every robot to desired direction. This approach can be applied not only to model swarm dynamics but also to quickly verify its emergent behavior. The simulation in MATLAB gives interesting insight into emergent behavior of the swarm over time, which other wise requires expensive experimentation.