Now showing items 1-20 of 1759

    • PROSET - A Language for Prototyping with Sets 

      Doberkat E; Franke W; Gutenbeil U; Hasselbring W; Lammers U; Pahl C (IEEE, 1992)
      We discuss the prototyping language PROSET(Prototyping with Sets) as a language for experimental and evolutionary prototyping, focusing its attention on algorithm design. Some of PROSET's features include generative ...
    • Proposing measurements in dynamic systems 

      Gamper J; Nejdl W (Morgan Kaufmann Publishers, 1995)
      Proposing measurements in diagnosis systems for static systems is a well understood task. Usually, entropy based approaches are used, sometimes extended by cost and other considerations. How to do the same task in dynamic ...
    • Describing Database Objects in a Concept Language Environment 

      Artale A; Cesarini F; Soda G (1996)
      We formally investigate the structural similarities and differences existing between object database models and concept languages establishing a correspondence between the two environments. Object database models deal with ...
    • Evaluation of main memory join algorithms for joins with subset join predicates 

      Helmer, S; Moerkotte, G (Morgan Kaufmann Publishers, 1997)
      Current data models like the NF2 model and object-oriented models support set-valued attributes. Hence, it becomes possible to have join predicates based on set comparison. This paper introduces and evaluates two main ...
    • An Epistemic Operator for Description Logics 

      Donini, FM; Lenzerini, M; Nardi, D; Nutt, W; Schaerf, A (Elsevier, 1998)
      Description logics (also called terminological logics, or concept languages) are fragments of first-order logic that provide a formal account of the basic features of frame-based systems. However, there are aspects of ...
    • Diag-Join: An Opportunistic Join Algorithm for 1:N Relationships 

      Helmer, S; Westmann, T; Moerkotte, G (Morgan Kaufmann Publishers Inc., 1998)
      Time of creation is one of the predominant (often implicit) clustering strategies found not only in Data Warehouse systems: line items are created together with their corresponding order, objects are created together with ...
    • Index structures for efficiently accessing fuzzy data including cost models and measurements 

      Boss, B; Helmer, S (Elsevier, 1999)
      Recently, the call for database management systems (DBMS) with uncertainty capabilities is getting stronger. Many of the existing approaches to modeling uncertainty in database management systems are based on the theory ...
    • Temporal ER modelling with description logics 

      Artale A; Franconi E (Springer, 1999)
      Recent efforts in the Conceptual Modelling community have been devoted to properly capturing time-varying information. Various temporally enhanced Entity-Relationship (ER) models have been proposed that are intended to ...
    • Mobile computing in outdoor environments 

      Ancona M; Dodero G; Gianuzzi V (Association for Computing Machinery, 1999)
      The paper describes an experience in developing and using a system for real-time field support to archaeological excavations.The experience is made possible by using mobile computers in outdoor environments, like archaeological ...
    • Efficient use of parallel libraries on heterogeneous Networks of Workstations 

      Clematis, A; Dodero, GM; Gianuzzi, V (Elsevier, 2000)
      The paper is motivated by efficiency considerations about porting mathematical software from Massively Parallel Processors (MPPs) to Networks of Workstations (NOWs). Heterogeneity of the network is the major obstacle to ...
    • The implementation and performance of compressed databases 

      Westmann, T; Kossmann, D; Helmer, S; Moerkotte, G (Association for Computing Machinery; 1999, 2000)
      In this paper, we show how compression can be integrated into a relational database system. Specifically, we describe how the storage manager, the query execution engine, and the query optimizer of a database system can ...
    • Integrating knowledge-based configuration systems by sharing functional architectures 

      Felfernig A; Friedrich G; Jannach D; Zanker M (Springer, 2000)
      Configuration problems are a thriving application area for declarative knowledge representation that experiences a constant increase in size and complexity of knowledge bases. However, today’s configurators are designed ...
    • A Framework for a markup language for the definition of scalable user interfaces 

      Tkalcic M; Tasic JF (EC, 2000)
      In this paper we present a novel framework for a markup language for the definition of user interfaces. Such framework includes the possibility and mechanisms for user interfaces adaptability and scalability. The typical ...
    • Cooperating configuration agents supporting supply chain integration of customizable products 

      Felfernig A; Friedrich G; Jannach D; Zanker M (IEEE Computer Society, 2000)
      The integration of configuration systems for supporting the supply-chain management of configurable products and services is still an open research issue. Current configurator approaches are designed for solving local ...
    • Diagrammatic Acquisition of Functional Knowledge for Product Configuration Systems with the Unified Modeling Language 

      Felfernig, A; Zanker, M (Springer, 2000)
      Shorter product cycles, lower prices of products, and the production of goods that are tailored to the customers needs made knowledge based product configuration systems a great success of AI technology. However, configuration ...
    • Modal Logics for Reasoning about Object-based Component Composition 

      Pahl C (British Computer Society, 2000)
      Component-oriented development of software supports the adaptability and maintainability of large systems, in particular if requirements change over time and parts of a system have to be modified or replaced. The software ...
    • Contextual diagrams as structuring mechanisms for designing configuration knowledge bases in UML 

      Felfernig, A; Jannach, D; Zanker, M (Springer, 2000)
      Lower prices, shorter product cycles, and the customer individual production of highly variant products are the main reasons for the success of product configuration systems in various application domains (telecommunication ...
    • Studies for optimization of data analysis queries for HEP using HERA-B commissioning data 

      Amaral, V; Moerkotte, G; Amorim, A; Helmer, S (Science Press NY Ltd., 2001)
      In this paper we present an overview of the ongoing studies to build up a framework that supports the analysis after the reprocessing phase. This framework aims to develop a standard data query language for the HEP community. ...
    • Indexing fuzzy data 

      Helmer, S (IFSA/NAFIPS, 2001)
      Providing efficient query processing in database systems is one step in gaining acceptance of such systems by end users. We propose several techniques for indexing fuzzy sets in databases to improve the query evaluation ...
    • Interactivity and integration in virtual courses 

      Pahl C (IEEE, 2001)
      Web-based virtual courses focussing on content delivery only have turned out not to be as successful as expected, We will investigate reasons and suggest some remedies using our own virtual Database course for illustration. ...