Now showing items 1017-1036 of 1759

    • OBDA Beyond Relational DBs: A Study for MongoDB 

      Botoeva E; Calvanese D; Cogrel B; Rezk M; Xiao G (CEUR-WS, 2016)
      The database landscape has been significantly diversified during the last decade, resulting in the emergence of a variety of non-relational (also called NoSQL) databases, e.g., XML and JSON-document databases, key-value ...
    • OBDA Constraints for Effective Query Answering 

      Hovland D; Lanti D; Rezk M; Xiao G (Springer, 2016)
      In Ontology Based Data Access (OBDA) users pose SPARQL queries over an ontology that lies on top of relational data-sources. These queries are translated on-the-fly into SQL queries by OBDA systems. Standard SPARQL-to-SQL ...
    • OBDA for Log Extraction in Process Mining 

      Calvanese D; Kalayci TE; Montali M; Santoso A (Springer, 2017)
      Process mining is an emerging area that synergically combines model-based and data-oriented analysis techniques to obtain useful insights on how business processes are executed within an organization. Through process mining, ...
    • OBDA Over Non-Relational Databases 

      Botoeva E; Calvanese D; Cogrel B; Rezk M; Xiao G (CEUR-WS, 2016)
      The database landscape has been significantly diversified during the last decade, resulting in the emergence of a variety of non-relational (also called NoSQL) databases, e.g., XML and JSON-document databases, key-value ...
    • OBDA with the Ontop Framework 

      Calvanese D; Cogrel B; Guzel Kalayci E; Komla Ebri S; Kontchakov R; Lanti D; Rezk M; Rodriguez-Muro M; Xiao G (Curran, 2015)
      Ontology-based data access (OBDA) has become a popular paradigm for accessing data stored in legacy sources using Semantic Web technologies. In the OBDA setting, users access the data through a conceptual layer, which ...
    • Object-Centric Behavioral Constraints: Integrating Data and Declarative Process Modelling 

      Artale A; Montali M; Tritini S; van der Aalst WMP (CEUR-WS.org, 2017)
    • Object-oriented software extensions in practice 

      Robbes R; Röthlisberger D; Tanter É (Kluwer Academic Publishers, 2015)
      As software evolves, data types have to be extended, possibly with new data variants or new operations. Object-oriented design is well-known to support data extensions well. In fact, most popular books showcase data ...
    • Observation and abstract behaviour in specification and implementation of state-based systems 

      Pahl C (British Computer Society, 2001)
      Classical algebraic specification is an accepted framework for specification. A criticism which applies is the fact that it is functional, not based on a notion of state as most software development and implementation ...
    • An observational user study for group recommender systems in the tourism domain 

      Delic A; Neidhardt J; Nguyen TN; Ricci G (2018)
      In this article we argue and give evidence that the research on group recommender systems must look more carefully at the dynamics of group decision-making in order to produce technologies that will be truly beneficial for ...
    • OCL-Lite: A decidable (yet expressive) fragment of OCL 

      Queralt A; Artale A; Calvanese D; Teniente E (CEUR-WS.org, 2012)
      UML has become a de facto standard in conceptual modeling. Class diagrams in UML allow one to model the data in the domain of interest by specifying a set of graphical constraints. However, in most cases one needs to provide ...
    • OCL-Lite: Finite reasoning on UML/OCL conceptual schemas 

      Queralt A; Artale A; Calvanese D; Teniente E (2012)
      To ensure the quality of an information system we must guarantee the correctness of the conceptual schema that represents the knowledge about its domain. The high expressivity of UML schemas annotated with textual OCL ...
    • Off-diagonal low-rank preconditioner for difficult PageRank problems 

      Shen ZL; Huang TZ; Carpentieri B; Wen C; Gu XM; Tan XY (North-Holland, 2019)
      PageRank problem is the cornerstone of Google search engine and is usually stated as solving a huge linear system. Moreover, when the damping factor approaches 1, the spectrum properties of this system deteriorate rapidly ...
    • On first-order μ-calculus over situation calculus action theories 

      Calvanese D; De Giacomo G; Montali M; Patrizi F (AAAI Press, 2016)
      In this paper we study verification of situation calculus action theories against first-order mu-calculus with quantification across situations. Specifically, we consider muLa and muLp, the two variants of mu-calculus ...
    • On Help and Interpersonal Control 

      Bottazzi E; Troquard N (Springer, 2015)
      Help is not much considered in the literature of analytic social philosophy. According to Tuomela (Cooperation – a philosophical study, Springer, 2000), when a helps an agent b (1) a contributes to the achievement of b’s ...
    • On how often code is cloned across repositories 

      Schwarz N; Lungu M; Robbes R (IEEE Computer Society, 2012)
      Detecting code duplication in large code bases, or even across project boundaries, is problematic due to the massive amount of data involved. Large-scale clone detection also opens new challenges beyond asking for the ...
    • On Metric Temporal Description Logics 

      Gutierrez-Basulto V; Ozaki A; Jung J (IOS Press, 2016)
      We introduce metric temporal description logics (mTDLs) as combinations of the classical description logic ALC with (a) LTLbin, an extension of the temporal logic LTL with succinctly represented intervals, and (b) metric ...
    • On Non-normal Modal Description Logics 

      Dalmonte T; Mazzullo A; Ozaki A (CEUR-WS, 2019)
      Non-normal modal logics based on neighbourhood semantics can be used to formalise normative, epistemic and coalitional reasoning in autonomous and multi-agent systems, since they do not validate principles known to be ...
    • On porting software visualization tools to the web 

      D'Ambros M; Lanza M; Lungu M; Robbes R (2011)
      Software systems are hard to understand due to the complexity and the sheer size of the data to be analyzed. Software visualization tools are a great help as they can sum up large quantities of data in dense, meaningful ...
    • On Rewriting and Answering Queries in OBDA Systems for Big Data 

      Calvanese D; Horrocks I; Jiménez-Ruiz E; Kharlamov E; Meier M; Rodriguez-Muro M; Zheleznyakov D (RWTH, 2013)
      The project Optique aims at providing an end-to-end solution for scalable access to Big Data integration, were end users will formulate queries based on a familiar conceptualization of the underlying domain. From the users ...
    • On Simplification of Schema Mappings 

      Calvanese D; De Giacomo G; Lenzerini M; Vardi M (2013)
      A schema mapping is a formal specification of the relationship holding between the databases conforming to two given schemas, called source and target, respectively. While in the general case a schema mapping is specified ...