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A Scheme for Integrating Concrete Domains into Concept Languages
, 1991
"... A drawback which concept languages based on klone have is that all the terminological knowledge has to be defined on an abstract logical level. In many applications, one would like to be able to refer to concrete domains and predicates on these domains when defining concepts. Examples for such conc ..."
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Cited by 262 (20 self)
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A drawback which concept languages based on klone have is that all the terminological knowledge has to be defined on an abstract logical level. In many applications, one would like to be able to refer to concrete domains and predicates on these domains when defining concepts. Examples for such concrete domains are the integers, the real numbers, or also nonarithmetic domains, and predicates could be equality, inequality, or more complex predicates. In the present paper we shall propose a scheme for integrating such concrete domains into concept languages rather than describing a particular extension by some specific concrete domain. We shall define a terminological and an assertional language, and consider the important inference problems such as subsumption, instantiation, and consistency. The formal semantics as well as the reasoning algorithms are given on the scheme level. In contrast to existing klone based systems, these algorithms will be not only sound but also complete. The...
A Temporal Description Logic for Reasoning about Actions and Plans
 Journal of Artificial Intelligence Research
, 1998
"... A class of intervalbased temporal languages for uniformly representing and reasoning about actions and plans is presented. Actions are represented by describing what is true while the action itself is occurring, and plans are constructed by temporally relating actions and world states. The tempo ..."
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Cited by 87 (18 self)
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A class of intervalbased temporal languages for uniformly representing and reasoning about actions and plans is presented. Actions are represented by describing what is true while the action itself is occurring, and plans are constructed by temporally relating actions and world states. The temporal languages are members of the family of Description Logics, which are characterized by high expressivity combined with good computational properties. The subsumption problem for a class of temporal Description Logics is investigated and sound and complete decision procedures are given. The basic language TLF is considered #rst: it is the composition of a temporal logic TL # able to express interval temporal networks # together with the nontemporal logic F # a Feature Description Logic. It is proven that subsumption in this language is an NPcomplete problem. Then it is shown how to reason with the more expressive languages TLUFU and TLALCF . The former adds disjunction both at...
Terminological Reasoning with Constraint Networks and an Application to Plan Recognition
, 1992
"... Terminological systems, such as KLONE and KRep, are widely used in AI to represent and reason with concept descriptions. They compute subsumption relations between concepts and automatically classify concepts into a taxonomy. Each concept in the taxonomy describes a set of possible instances ..."
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Cited by 62 (5 self)
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Terminological systems, such as KLONE and KRep, are widely used in AI to represent and reason with concept descriptions. They compute subsumption relations between concepts and automatically classify concepts into a taxonomy. Each concept in the taxonomy describes a set of possible instances which are a superset of those described by its descendants. One limitation of current systems is their inability to handle complex compositions of concepts, such as constraint networks where each node is described by an associated concept. For example, plans are often represented (in part) as collections of actions related by a rich variety of temporal constraints. The TREX system integrates terminological reasoning with constraint network reasoning to classify such plans, producing a "terminological" plan library. TREX also introduces a new view of plan recognition as a process which dynamically partitions the plan library by modalities, e.g., necessary, possible and impo...
Temporalizing description logics
, 1998
"... Traditional rst order predicate logic is known to be designed for representing and manipulating static knowledge (e.g. mathematical theories). So are manyof its applications. Knowledge representation systems based on concept description logics are not exceptions. ..."
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Cited by 59 (20 self)
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Traditional rst order predicate logic is known to be designed for representing and manipulating static knowledge (e.g. mathematical theories). So are manyof its applications. Knowledge representation systems based on concept description logics are not exceptions.
Modal description logics: Modalizing roles
 Fundam. Inform
, 1999
"... In this paper, we construct a new concept description language intended for representing dynamic and intensional knowledge. The most important feature distinguishing this language from its predecessors in the literature is that it allows applications of modal operators to all kinds of syntactic term ..."
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Cited by 31 (14 self)
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In this paper, we construct a new concept description language intended for representing dynamic and intensional knowledge. The most important feature distinguishing this language from its predecessors in the literature is that it allows applications of modal operators to all kinds of syntactic terms: concepts, roles and formulas. Moreover, the language may contain both local (i.e., statedependent) and global (i.e., stateindependent) concepts, roles and objects. All this provides us with the most complete and natural means for re ecting the dynamic and intensional behaviour of application domains. We construct a satis ability checking (mosaictype) algorithm for this language (based on ALC) in(i) arbitrary multimodal frames, (ii) frames with universal accessibility relations (for knowledge) and (iii) frames with transitive, symmetrical and euclidean relations (for beliefs). On the other hand, it is shown that the satisfaction problem becomes undecidable if the underlying frames are arbitrary strict linear orders, hN; <i, or the language contains the common knowledge operator for n 2 agents. 1
LTL over description logic axioms
 In Proceedings of DL08, CEUR Workshop Proceedings. CEURWS.org
, 2008
"... In many applications of Description Logics (DLs) [7], such as the use of DLs as ontology languages or conceptual modeling languages, being able to represent dynamic aspects of the application domain would be quite useful. This is, for instance, the case if one wants to use DLs as conceptual modeling ..."
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Cited by 18 (3 self)
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In many applications of Description Logics (DLs) [7], such as the use of DLs as ontology languages or conceptual modeling languages, being able to represent dynamic aspects of the application domain would be quite useful. This is, for instance, the case if one wants to use DLs as conceptual modeling languages
The Product of Converse PDL and Polymodal K
 Journal of Logic and Computation
"... The product of two modal logics L1 and L2 is the modal logic determined by the class of frames of the form F G such that F and G validate L1 and L2, respectively. This paper proves the decidability of the product of converse PDL and polymodal K. Decidability results for products of modal logics of k ..."
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Cited by 15 (3 self)
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The product of two modal logics L1 and L2 is the modal logic determined by the class of frames of the form F G such that F and G validate L1 and L2, respectively. This paper proves the decidability of the product of converse PDL and polymodal K. Decidability results for products of modal logics of knowledge as well as temporal logics and polymodal K are discussed. All those products form rather expressive but still decidable fragments of modal predicate logics. Based on the equivalence of polymodal K and the description logic ALC we shall discuss the obtained fragments, extend the expressive power a bit, and compare them with other modal description logics. 1
Subsumption and Recognition of Heterogeneous Constraint Networks
 In Proceedings of CAIA94
, 1994
"... Terminological knowledge representation (tkr) systems such as klone are widely used in AI to construct concept taxonomies based on subsumption inferences. However, current tkr systems are unable to represent temporal patterns or recognize instances of such patterns from ongoing observations. Motiva ..."
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Cited by 14 (3 self)
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Terminological knowledge representation (tkr) systems such as klone are widely used in AI to construct concept taxonomies based on subsumption inferences. However, current tkr systems are unable to represent temporal patterns or recognize instances of such patterns from ongoing observations. Motivated by applications such as service personnel dispatching and plan recognition for interactive user interfaces, we extend tkr by introducing terminological QME networks. In QME networks, nodes are tkr concepts and arcs are qualitative constraints between temporal intervals associated with nodes, metric constraints between endpoints of temporal intervals, and equality constraints among roles of different concepts. We use QME networks to represent patterns, and define QME network subsumption, which enables us to organize a pattern library into a taxonomy. We also develop a terminological approach to predictive pattern recognition based on subsumption and a related notion of compatibility. We a...