Now showing 1 - 10 of 68
  • Publication
    Requirements for workflow modeling in P2P - workflows derived from collaboration establishment
    ( 2004)
    Wombacher, A.
    ;
    Aberer, K.
    Web services advocate loosely coupled systems, although current applications are limited to centrally controlled structures. The reason for this limitation is the lack of a method for deciding collaboration consistency, that is deadlock freeness and boundedness, in a decentralized way. In particular, an intuitive approach classifies collaborations incorrectly being inconsistent due to the loss of information introduced by the decentralization. In this paper we identify loss of message ordering and message parameter value constraints caused by the decentralization to be the reasons for incorrect decision results. The proposed approach to overcome this issue is to explicate these constraints, which cannot represent in common workflow models.
  • Publication
    Configuration of distributed message converter systems
    ( 2004)
    Risse, T.
    ;
    Aberer, K.
    ;
    Wombacher, A.
    ;
    Surridge, M.
    ;
    Taylor, S.
    Finding a configuration of a distributed system satisfying performance goals is a complex search problem that involves many design parameters, like hardware selection, job distribution and process configuration. Performance models are a powerful tool to analyze potential system configurations, however, their evaluation is expensive, such that only a limited number of possible configurations can be evaluated. In this paper we present a systematic method to find a satisfactory configuration with feasible effort, based on a two-step approach. First, performing a queuing network analysis a hardware configuration is determined and then a software configuration is incrementally optimized by simulating Layered Queuing Network models. We applied this method to the design of performant EDI converter systems in the financial domain, where increasing message volumes need to be handled due to the growing importance of B2B interaction.
  • Publication
    Emergent semantics - Extended and revised version of the DASFAA 2004 paper
    ( 2004)
    Aberer, K.
    ;
    Catarci, T.
    ;
    Cudre-Mauroux, P.
    ;
    Dillon, T.
    ;
    Grimm, S.
    ;
    Hacid, M.-S.
    ;
    Illarramendi, A.
    ;
    Jarrar, M.
    ;
    Kashyap, V.
    ;
    Mecella, M.
    ;
    Mena, E.
    ;
    Neuhold, E.J.
    ;
    Ouksel, A.M.
    ;
    Risse, T.
    ;
    Scannapieco, M.
    ;
    Saltor, F.
    ;
    Santis, L. de
    ;
    Spaccapietra, S.
    ;
    Staab, S.
    ;
    Studer, R.
    ;
    Troyer, O. de
  • Publication
    Emergent semantics
    ( 2004)
    Aberer, K.
    ;
    Cudre-Mauroux, P.
    ;
    Ouksel, A.M.
    ;
    Catarci, T.
    ;
    Hacid, M.-S.
    ;
    Illarramendi, A.
    ;
    Kashyap, V.
    ;
    Mecella, M.
    ;
    Mena, E.
    ;
    Neuhold, E.J.
    ;
    Troyer, O. de
    ;
    Risse, T.
    ;
    Scannapieco, M.
    ;
    Saltor, F.
    ;
    Santis, L. de
    ;
    Spaccapietra, S.
    ;
    Staab, S.
    ;
    Studer, R.
  • Publication
    Online Scheduling in Distributed Message Converter Systems
    ( 2001)
    Risse, T.
    ;
    Wombacher, A.
    ;
    Surridge, M.
    ;
    Taylor, S.
    ;
    Aberer, K.
  • Publication
    Configuration of distributed message converter systems using performance modeling
    ( 2001)
    Aberer, K.
    ;
    Risse, T.
    ;
    Wombacher, A.
    To find a configuration of a distributed system satisfying performance goals is a complex search problem that involves many design parameters, like hardware selection, job distribution and process configuration. Performance models are a powerful tool to analyse potential system configurations, however, their evaluation is expensive, such that only a limited number of possible configurations can be evaluated. We present a systematic method to find a satisfactory configuration with feasible effort, based on a two-step approach. First, using performance estimates, a hardware configuration is determined and then the software configuration is incrementally optimized, evaluating Layered Queueing Network models. We applied this method to the design of performant EDI converter systems in the financial domain, where increasing message volumes need to be handled due to the increasing importance of B2B interaction.
  • Publication
    A language for information commerce processes
    ( 2001)
    Aberer, K.
    ;
    Wombacher, A.
  • Publication
    Efficient processing of voluminous EDI documants
    ( 2000)
    Risse, T.
    ;
    Wombacher, A.
    ;
    Aberer, K.
  • Publication
    Query Relaxation and Evaluation Optimization in Biological Databases
    ( 2000)
    Chen, Y.
    ;
    Che, D.
    ;
    Aberer, K.
    In this paper, a new technique is developed to support the query relaxation in biological databases. Query relaxation is required due to the fact that queries tend not to be expressed exactly by the users, especially in scientific databases like biological databases, in which complex domain knowledge is heavily involved. To treat this problem, we propose the concept of the so-called fuzzy equivalence classes to capture an important kind of domain knowledge that is used to relax queries. This concept is further integrated with the canonical techniques for pattern searching such as the position tree and automaton theory. As a result, fuzzy queries produced through relaxation can be efficiently evaluated. This method has been successfully utilized in a practical biological database - the GPCRDB.