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24
Adding temporal constraints to XML schema
- IEEE Transactions on Knowledge and Data Engineering
, 2012
"... Abstract-If past versions of XML documents are retained, what of the various integrity constraints defined in XML Schema on those documents? This paper describes how to interpret such constraints as sequenced constraints, applicable at each point in time. We also consider how to add new variants th ..."
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Abstract-If past versions of XML documents are retained, what of the various integrity constraints defined in XML Schema on those documents? This paper describes how to interpret such constraints as sequenced constraints, applicable at each point in time. We also consider how to add new variants that apply across time, so-called non-sequenced constraints. Our approach supports temporal documents that vary over both valid and transaction time, whose schema can vary over transaction time. We do this by replacing the schema with a (possibly time-varying) temporal schema and replacing the document with a temporal document, both of which are upward compatible with conventional XML and with conventional tools like XMLLINT, which we have extended to support the temporal constraints introduced here.
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 representation and reasoning for the semantic web
, 2003
"... We introduce period names, a new approach for quantita-tive and qualitative temporal representation and reasoning of resources in the Semantic Web. Our work has been imple-mented into the Bremen University Semantic Translator for Enhanced Retrieval (BUSTER). This enables us to perform a query of the ..."
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We introduce period names, a new approach for quantita-tive and qualitative temporal representation and reasoning of resources in the Semantic Web. Our work has been imple-mented into the Bremen University Semantic Translator for Enhanced Retrieval (BUSTER). This enables us to perform a query of the form
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
A basic characterization of relation migration
"... Abstract. Representing and reasoning over evolving objects has been investigated widely. Less attention has been devoted to the similar notion of relation migration, i.e., how tuples of a relation (ORM facts) can evolve along time. We identify different ways how a relation can change over time and g ..."
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Abstract. Representing and reasoning over evolving objects has been investigated widely. Less attention has been devoted to the similar notion of relation migration, i.e., how tuples of a relation (ORM facts) can evolve along time. We identify different ways how a relation can change over time and give a logicbased semantics to the notion of relation migration to capture its behaviour. We also introduce the notion of lifespan of a relation and clarify the interactions between object migration and relation migration. Its use in graphical conceptual data modelling is illustrated with a minor extension to ORM2 so as to more easily communicate such constraints with domain experts. 1
C.M.: Essential, mandatory, and shared parts in conceptual data models
- Innovations in Information Systems modeling: Methods and Best Practices. IGI Global (2008) 17–52
"... Abstract. This chapter focuses on formally representing life cycle semantics of part-whole relations in conceptual data models by utilizing the temporal modality. We approach this by resorting to the temporal conceptual data modeling language ERV T and extend it with the novel notion of status relat ..."
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Abstract. This chapter focuses on formally representing life cycle semantics of part-whole relations in conceptual data models by utilizing the temporal modality. We approach this by resorting to the temporal conceptual data modeling language ERV T and extend it with the novel notion of status relations. This enables a precise axiomatization of the constraints for essential parts and wholes compared to mandatory parts and wholes, as well as introduction of temporally suspended partwhole relations. To facilitate usage in the conceptual stage, a set of closed questions and decision diagram are proposed. The long-term objectives are to ascertain which type of shareability and which lifetime aspects are possible for part-whole relations, investigate the formal semantics for sharability, and how to model these kind of differences in conceptual data models. 1
Constraints for representing transforming entities in bio-ontologies
"... Abstract. Things change—develop, mature morph—but not everything in the same way. Representing this knowledge in ontologies faces issues on three fronts: what the category of the participating objects are, which type of relations they involve, and where constraints should be added. More precise dist ..."
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Abstract. Things change—develop, mature morph—but not everything in the same way. Representing this knowledge in ontologies faces issues on three fronts: what the category of the participating objects are, which type of relations they involve, and where constraints should be added. More precise distinctions can be made by using OntoClean’s properties and a novel status property that is generalised from formal temporal conceptual data modeling. Criteria are identified, formulated in 17 additional constraints, and assessed on applicability for representing transformations more accurately. This enables developers of (bio-)ontologies to represent and relate entities more precisely, such as monocyte & macrophage and healthy & unhealthy organs. 1
Unifying industry-grade class-based conceptual data modeling languages with CMcom
"... Abstract. From the side of modelers and early-adopter industry, interest in reasoning over conceptual models and other online usage of conceptual models is growing. To obtain a more precise insight in the characteristics of the main conceptual modeling languages, we define the (semi-)standardized OR ..."
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Abstract. From the side of modelers and early-adopter industry, interest in reasoning over conceptual models and other online usage of conceptual models is growing. To obtain a more precise insight in the characteristics of the main conceptual modeling languages, we define the (semi-)standardized ORM, ORM2, UML, ER, and EER diagram languages in terms of the new generic conceptual data modeling language CMcom that is based on the DL language DLR ifd. CMcom has the most expressive common denominator with these languages. CMcom advances prospects for automated, online, interoperability among diverse conceptual data models and ensures compatibility with and between industrygrade conceptual data modeling languages. 1
Capturing Telic/Atelic Temporal Data Semantics: Generalizing Conventional Conceptual Models
"... Abstract—Time provides context for all our experiences, cognition, and coordinated collective action. Prior research in linguistics, artificial intelligence and temporal databases suggests the need to differentiate between temporal facts with goal-related semantics (i.e., telic) from those are intri ..."
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Abstract—Time provides context for all our experiences, cognition, and coordinated collective action. Prior research in linguistics, artificial intelligence and temporal databases suggests the need to differentiate between temporal facts with goal-related semantics (i.e., telic) from those are intrinsically devoid of culmination (i.e., atelic). To differentiate between telic and atelic data semantics in conceptual database design, we propose an annotation-based temporal conceptual model that generalizes the semantics of a conventional conceptual model. Our temporal conceptual design approach involves: 1) capturing “what ” semantics using a conventional conceptual model; 2) employing annotations to differentiate between telic and atelic data semantics that help capture “when ” semantics; 3) specifying temporal constraints, specifically non-sequenced semantics, in the temporal data dictionary as metadata. Our proposed approach provides a mechanism to represent telic/atelic temporal semantics using temporal annotations. We also show how these semantics can be formally defined using constructs of the conventional conceptual model and axioms in first-order logic. Via what we refer to as the “semantics of composition, ” i.e., semantics implied by the interaction of annotations, we illustrate the logical consequences of representing telic/atelic data semantics during temporal conceptual design. Index Terms—temporal database, conceptual modeling, data semantics, temporal conceptual model, database design. 1