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Auflistung nach Autor:in "Baader, Franz"

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  • Zeitschriftenartikel
    Decidability and Complexity of Fuzzy Description Logics
    (KI - Künstliche Intelligenz: Vol. 31, No. 1, 2017) Baader, Franz; Borgwardt, Stefan; Peñaloza, Rafael
    Fuzzy description logics (FDLs) have been introduced to represent concepts for which membership cannot be determined in a precise way, i.e., where instead of providing a strict border between being a member and not being a member, it is more appropriate to model a gradual change from membership to non-membership. First approaches for reasoning in FDLs where based either on a reduction to reasoning in classical description logics (DLs) or on adaptations of reasoning approaches for DLs to the fuzzy case. However, it turned out that these approaches in general do not work if expressive terminological axioms, called general concept inclusions (GCIs), are available in the FDL. The goal of this project was a comprehensive study of the border between decidability and undecidability for FDLs with GCIs, as well as determining the exact complexity of the decidable logics. As a result, we have provided an almost complete classification of the decidability and complexity of FDLs with GCIs.
  • Zeitschriftenartikel
    Deduktion: von der Theorie zur Anwendung
    (Informatik-Spektrum: Vol. 33, No. 5, 2010) Baader, Franz; Beckert, Bernhard; Nipkow, Tobias
  • Zeitschriftenartikel
    Editorial
    (Informatik-Spektrum: Vol. 35, No. 4, 2012) Baader, Franz; Thomas, Wolfgang
  • Zeitschriftenartikel
    Role-Value Maps and General Concept Inclusions in the Minimal Description Logic with Value Restrictions or Revisiting Old Skeletons in the DL Cupboard
    (KI - Künstliche Intelligenz: Vol. 34, No. 3, 2020) Baader, Franz; Théron, Clément
    We investigate the impact that general concept inclusions and role-value maps have on the complexity and decidability of reasoning in the description logic $$\mathcal{FL}_0$$ FL 0 . On the one hand, we give a more direct proof for ExpTime-hardness of subsumption w.r.t. general concept inclusions in $$\mathcal{FL}_0$$ FL 0 . On the other hand, we determine restrictions on role-value maps that ensure decidability of subsumption, but we also show undecidability for the cases where these restrictions are not satisfied.
  • Zeitschriftenartikel
    Semantic Technologies for Situation Awareness
    (KI - Künstliche Intelligenz: Vol. 34, No. 4, 2020) Baader, Franz; Borgwardt, Stefan; Koopmann, Patrick; Thost, Veronika; Turhan, Anni-Yasmin
    The project “Semantic Technologies for Situation Awareness” was concerned with detecting certain critical situations from data obtained by observing a complex hard- and software system, in order to trigger actions that allow this system to save energy. The general idea was to formalize situations as ontology-mediated queries, but in order to express the relevant situations, both the employed ontology language and the query language had to be extended. In this paper we sketch the general approach and then concentrate on reporting the formal results obtained for reasoning in these extensions, but do not describe the application that triggered these extensions in detail.
  • Zeitschriftenartikel
    Small is Again Beautiful in Description Logics
    (KI - Künstliche Intelligenz: Vol. 24, No. 1, 2010) Baader, Franz; Lutz, Carsten; Turhan, Anni-Yasmin
    The Description Logic (DL) research of the last 20 years was mainly concerned with increasing the expressive power of the employed description language without losing the ability of implementing highly-optimized reasoning systems that behave well in practice, in spite of the ever increasing worst-case complexity of the underlying inference problems. OWL DL, the standard ontology language for the Semantic Web, is based on such an expressive DL for which reasoning is highly intractable. Its sublanguage OWL Lite was intended to provide a tractable version of OWL, but turned out to be only of a slightly lower worst-case complexity than OWL DL. This and other reasons have led to the development of two new families of light-weight DLs, $\mathcal{EL}$ and DL-Lite, which recently have been proposed as profiles of OWL 2, the new version of the OWL standard. In this paper, we give an introduction to these new logics, explaining the rationales behind their design.
  • Zeitschriftenartikel
    What’s new in Description Logics
    (Informatik-Spektrum: Vol. 34, No. 5, 2011) Baader, Franz
    Mainstream research in Description Logics (DLs) until recently concentrated on increasing the expressive power of the employed description language while keeping standard inference problems like subsumption and instance manageable in the sense that highly optimized reasoning procedures for them behave well in practice. One of the main successes of this line of research was the adoption of OWL DL, which is based on an expressive DL, as the standard ontology language for the Semantic Web.More recently, there has been a growing interest in more light-weight DLs, and in other kinds of inference problems, mainly triggered by need in applications with large-scale ontologies. In this paper, we first review the DL research leading to the very expressive DLs with practical inference procedures underlying OWL, and then sketch the recent development of light-weight DLs and novel inference procedures.