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V.: Temporal query answering in the description logic DL-Lite
- In: Proc. of the 9th Int. Symposium on Frontiers of Combining Systems (FroCoS’13). LNCS
, 2013
"... Abstract. Ontology-based data access (OBDA) generalizes query an-swering in relational databases. It allows to query a database by using the language of an ontology, abstracting from the actual relations of the database. For ontologies formulated in Description Logics of the DL-Lite family, OBDA can ..."
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Abstract. Ontology-based data access (OBDA) generalizes query an-swering in relational databases. It allows to query a database by using the language of an ontology, abstracting from the actual relations of the database. For ontologies formulated in Description Logics of the DL-Lite family, OBDA can be realized by rewriting the query into a classical first-order query, e.g. an SQL query, by compiling the information of the ontology into the query. The query is then answered using classical database techniques. In this paper, we consider a temporal version of OBDA. We propose a temporal query language that combines a linear temporal logic with queries over DL-Litecore-ontologies. This language is well-suited to ex-press temporal properties of dynamical systems and is useful in context-aware applications that need to detect specific situations. Using a first-order rewriting approach, we transform our temporal queries into queries over a temporal database. We then present three approaches to answer-ing the resulting queries, all having different advantages and drawbacks. 1
Complexity of Reasoning over Temporal Data Models
"... Abstract. We investigate the computational complexity of reasoning over temporal extensions of conceptual data models. The temporal conceptual models we analyse include the standard UML/EER ISA between entities and relationships, disjointness and covering, cardinality constraints and their refinemen ..."
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Abstract. We investigate the computational complexity of reasoning over temporal extensions of conceptual data models. The temporal conceptual models we analyse include the standard UML/EER ISA between entities and relationships, disjointness and covering, cardinality constraints and their refinements, multiplicity and key constraints; in the temporal dimension, we have timestamping, evolution and transition constraints, as well as lifespan cardinalities. We give a nearly comprehensive picture of the impact of these constraints on the complexity of reasoning, which can range from NLOGSPACE to undecidability.
Temporal Conceptual Modelling with DL-Lite
"... Conceptual modelling formalisms such as the Entity-Relationship model (ER) and Unified Modelling Language (UML) have become a de facto standard in database design by providing visual means to describe application domains in a declarative and reusable way. On the other hand, both ER and UML turned ou ..."
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Cited by 5 (2 self)
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Conceptual modelling formalisms such as the Entity-Relationship model (ER) and Unified Modelling Language (UML) have become a de facto standard in database design by providing visual means to describe application domains in a declarative and reusable way. On the other hand, both ER and UML turned out
Past and Future of DL-Lite
"... We design minimal temporal description logics that are capable of expressing various aspects of temporal conceptual data models and investigate their computational complexity. We show that, depending on the required types of temporal and atemporal constraints, the satisfiability problem for temporal ..."
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We design minimal temporal description logics that are capable of expressing various aspects of temporal conceptual data models and investigate their computational complexity. We show that, depending on the required types of temporal and atemporal constraints, the satisfiability problem for temporal knowledge bases in the resulting logics can be NLOGSPACE-, NP- and PSPACE-complete, as well as undecidable.
Temporal Query Answering in DL-Lite ∗
"... Context-aware applications try to detect specific situations within a changing environment (e.g. a computer system or air traffic observed by radar) in order to react accordingly. To gain information, the environment is observed by sensors (for a computer system, data about its resources is gathered ..."
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Context-aware applications try to detect specific situations within a changing environment (e.g. a computer system or air traffic observed by radar) in order to react accordingly. To gain information, the environment is observed by sensors (for a computer system, data about its resources is gathered by the operating
Tailoring Temporal Description Logics for Reasoning over Temporal Conceptual Models
"... Abstract. Temporal data models have been used to describe how data can evolve in the context of temporal databases. Both the Extended Entity-Relationship (EER) model and the Unified Modelling Language (UML) have been temporally extended to design temporal databases. To automatically check quality pr ..."
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Abstract. Temporal data models have been used to describe how data can evolve in the context of temporal databases. Both the Extended Entity-Relationship (EER) model and the Unified Modelling Language (UML) have been temporally extended to design temporal databases. To automatically check quality properties of conceptual schemas various encoding to Description Logics (DLs) have been proposed in the literature. On the other hand, reasoning on temporally extended DLs turn out to be too complex for effective reasoning ranging from 2EXPTIME up to undecidable languages. We propose here to temporalize the ‘light-weight’ DL-Lite logics obtaining nice computational results while still being able to represent various constraints of temporal conceptual models. In particular, we consider temporal extensions of DL-Lite N bool, which was shown to be adequate for capturing non-temporal conceptual models without relationship inclusion, and its fragment DL-Lite N core with most primitive concept inclusions, which are nevertheless enough to represent almost all types of atemporal constraints (apart from covering). 1
Using Provenance to Debug ChangingOntologies 1
"... On the Semantic Web ontologies evolve and are managed in a distributed setting, e.g. in biomedical databases. Changes are contributed by multiple persons or organizations at various points in time. Often, changes differ by certainty or trustworthiness. When judging changes of automatically inferred ..."
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On the Semantic Web ontologies evolve and are managed in a distributed setting, e.g. in biomedical databases. Changes are contributed by multiple persons or organizations at various points in time. Often, changes differ by certainty or trustworthiness. When judging changes of automatically inferred knowledge and when debugging such evolving ontologies, the provenance of axioms (e.g. agent, trust degree and modification time) needs to be taken into account. Providing and reasoning with rich provenance data for expressive ontology languages, however, is a non-trivial task. In this paper we propose a formalization of provenance, which allows for the computation of provenance for inferences and inconsistencies. It allows us to answer questions such as “When has this inconsistency been introduced and who is responsible for this change? ” as well as “Can I trust this inference?”. We propose a black box algorithm for reasoning with provenance, which is based on general pinpointing, and an optimization, which enables the use of provenance for debugging in real time even for very large and expressive ontologies, such as used in biomedical portals.
Temporal Query Answering w.r.t.
"... This revised version proves that the presented algorithm achieves a bounded history encoding. ..."
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This revised version proves that the presented algorithm achieves a bounded history encoding.
Reasoning with Temporal Properties over Axioms of DL-Lite
"... Recently, a lot of research has combined description logics (DLs) of the DL-Lite family with temporal formalisms. Such logics are proposed to be used for situation recognition and temporalized ontology-based data ac-cess. In this report, we consider DL-Lite-LTL, in which axioms formulated in a membe ..."
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Recently, a lot of research has combined description logics (DLs) of the DL-Lite family with temporal formalisms. Such logics are proposed to be used for situation recognition and temporalized ontology-based data ac-cess. In this report, we consider DL-Lite-LTL, in which axioms formulated in a member of the DL-Lite family are combined using the operators of propositional linear-time temporal logic (LTL). We consider the satisfiabil-ity problem of this logic in the presence of so-called rigid symbols whose interpretation does not change over time. In contrast to more expressive temporalized DLs, the computational complexity of this problem is the same as for LTL, even w.r.t. rigid symbols.
