@inproceedings {INPROC-2002-42, author = {Bernhard Mitschang}, title = {{A Necessity for CSCW in Design - The CHAMPAGNE Approach and Experience (invited)}}, booktitle = {A Necessity for CSCW in Design - The CHAMPAGNE Approach and Experience}, editor = {Uni Rio de Janiero}, address = {Rio de Janiero}, publisher = {The Seventh International Conference on Computer Supported Cooperative Work in Design}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--2}, type = {Conference Paper}, month = {September}, year = {2002}, language = {English}, cr-category = {H.2.4 Database Management Systems}, contact = {Bernhard Mitschang Bernhard.Mitschang@informatik.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Data Propagation: A Necessity for CSCW in Design - The CHAMPAGNE Approach and Experience (invited), in: The Seventh International Conference on Computer Supported Cooperative Work in Design, Rio de Janeiro, Brasil, 2002.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-42&engl=1} } @inproceedings {INPROC-2002-41, author = {Aiko Frank and Bernhard Mitschang}, title = {{A customizable shared information space to support concurrent design}}, booktitle = {Computer in Industry}, address = {Amsterdam}, publisher = {Elsevier Science Publishers B. V.}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, volume = {48}, pages = {45--57}, type = {Conference Paper}, month = {May}, year = {2002}, language = {English}, cr-category = {H.5.3 Group and Organization Interfaces}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Sharing data is an important aspect in distributed design environments and should be supported by an underlying system. Any synchronous access to data is conflict prone. Applying concurrency control and two phase commit are one option to be considered. But design processes also demand for cooperation between the designers. Negotiation about actions on the product under design and the early exchange of preliminary results are crucial issues. Controlled data access by itself does not fulfil all the needs for cooperation. We will present a new approach that relies on a concept and system model which integrates concurrent activities by a joint information space offering flexible protocols for cooperation on the shared objects. We will describe the customizability of the protocols to effectively support different cooperative scenarios.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-41&engl=1} } @inproceedings {INPROC-2002-18, author = {Carmen Constantinescu and Uwe Heinkel and Holger Meinecke}, title = {{A Data Change Propagation System for Enterprise Application Integration}}, booktitle = {The 2nd International Conference on Information Systems and Engneering (ISE 2002)}, editor = {Waleed W. Smari and Nordine Melab and Shu-Ching Chen}, address = {San Diego}, publisher = {The Society for Modeling and Simulation International}, institution = {University of Stuttgart, Faculty of Computer Science, Germany}, pages = {129--134}, type = {Conference Paper}, month = {July}, year = {2002}, isbn = {1-56555-251-2}, keywords = {information systems; integration of heterogeneous data sources; XML technology}, language = {English}, cr-category = {H.2.5 Heterogeneous Databases}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2002-18/INPROC-2002-18.pdf}, contact = {carmen.constantinescu@informatik.uni-stuttgart.de oder uwe.heinkel@informatik.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Applications of Parallel and Distributed Systems}, abstract = {Most enterprises have a diverse environment of heterogeneous and autonomous information systems. If the same data is relevant for several information systems, then data changes in one supplier system affect data stored in other demander systems. The process of exchanging changed data between systems, named change propagation, is based on dependencies established between these systems. The management of a single, integrated enterprise information system is often infeasible or too expensive, due to the autonomy of business units and the heterogeneity of their IT infrastructures. The solution is to support the enterprise by a generic approach able to manage data dependencies and to transform data stored in a source information system into data stored in the dependent information systems. We propose a loosely coupled system, called Stuttgart Information and Exploration System. Our prototype mainly consists of a data dependency specification tool, a propagation engine and a repository that stores all relevant objects for these components.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-18&engl=1} } @inproceedings {INPROC-2002-17, author = {Marcello Mariucci and Bernhard Mitschang}, title = {{On Making RAMSES an Earth Observation Application Framework}}, booktitle = {Proceedings of the 2nd International Conference on Information Systems and Engineering: ISE 2002; San Diego, California, July 14-18, 2002}, editor = {Waleed W. Smari and Nordine Melab and Shu-Ching Chen}, address = {San Diego}, publisher = {The Society for Modeling and Simulation International (SCS)}, institution = {University of Stuttgart, Faculty of Computer Science, Germany}, series = {Simulation Series}, volume = {34 (2)}, pages = {67--72}, type = {Conference Paper}, month = {July}, year = {2002}, isbn = {1-56555-251-2}, keywords = {Frameworks for Information Technologies, Software Architectures for Information Systems, Component-Based Designs, Service-Based Approaches}, language = {English}, cr-category = {H.4.m Information Systems Applications Miscellaneous}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2002-17/INPROC-2002-17.pdf}, contact = {For further information, please send an email to mariucci@informatik.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Applications of Parallel and Distributed Systems}, abstract = {RAMSES is one of the first large-scale prototypes of an operational Earth Observation (EO) application system. It implements a complex infrastructure for the extensive support of a thematic EO application system, which focuses on the detection and monitoring of oil spills. Since EO application systems are usually built on top of a set of generic functions, this paper analyses and assesses the RAMSES infrastructure in order to form a generic EO application framework. This framework should mainly support the collaborative development and customization of emerging EO application systems by maximizing the use of already existing system facilities. Furthermore, it should support the flexible extension and rapid reconfiguration of workflows as the business changes. Results of our analyses show that the RAMSES infrastructure does not cover all requirements of an EO application framework. We therefore introduce advanced design concepts and propose a new framework architecture that structurally controls the inherent complexity of the interdisciplinary domain of EO application systems.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-17&engl=1} } @inproceedings {INPROC-2002-12, author = {Ralf Rantzau and Carmen Constantinescu and Uwe Heinkel and Holger Meinecke}, title = {{Champagne: Data Change Propagation for Heterogeneous Information Systems}}, booktitle = {Proceedings of the International Conference on Very Large Databases (VLDB); Demonstration Paper; Hong Kong, August 20-23, 2002}, publisher = {Morgan Kaufmann}, institution = {University of Stuttgart, Faculty of Computer Science, Germany}, type = {Conference Paper}, month = {August}, year = {2002}, keywords = {data transformation; data integration; schema mapping}, language = {English}, cr-category = {H.2.5 Heterogeneous Databases}, contact = {rrantzau@acm.org}, department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Applications of Parallel and Distributed Systems}, abstract = {Flexible methods supporting the data interchange between autonomous information systems are important for today's increasingly heterogeneous enterprise IT infrastructures. Updates, insertions, and deletions of data objects in autonomous information systems often have to trigger data changes in other autonomous systems, even if the distributed systems are not integrated into a global schema. We suggest a solution to this problem based on the propagation and transformation of data using several XML technologies. Our prototype manages dependencies between the schemas of distributed data sources and allows to define and process arbitrary actions on changed data by manipulating all dependent data sources. The prototype comprises a propagation engine that interprets scripts based on a workflow specification language, a data dependency specification tool, a system administration tool, and a repository that stores all relevant information for these tools.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-12&engl=1} } @inproceedings {INPROC-2002-05, author = {Ralf Rantzau}, title = {{Frequent Itemset Discovery with SQL Using Universal Quantification}}, booktitle = {Proceedings of the International Workshop on Database Technologies for Data Mining (DTDM); Prague, Czech Republic, March 2002}, address = {Prague, Czech Republic}, publisher = {unknown}, institution = {University of Stuttgart, Faculty of Computer Science, Germany}, pages = {51--66}, type = {Conference Paper}, month = {March}, year = {2002}, keywords = {data mining; association rules; relational division; mining and database integration}, language = {English}, cr-category = {H.2.4 Database Management Systems, H.2.8 Database Applications}, contact = {rrantzau@acm.org}, department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Applications of Parallel and Distributed Systems}, abstract = {Algorithms for finding frequent itemsets fall into two broad classes: (1) algorithms that are based on non-trivial SQL statements to query and update a database, and (2) algorithms that employ sophisticated in-memory data structures, where the data is stored into and retrieved from flat files. Most performance experiments have shown that SQL-based approaches are inferior to main-memory algorithms. However, the current trend of database vendors to integrate analysis functionalities into their query execution and optimization components, i.e., ``closer to the data,'' suggests revisiting these results and searching for new, potentially better solutions. We investigate approaches based on SQL-92 and present a new approach called Quiver that employs universal and existential quantifications. This approach uses a table layout for itemsets, where a group of multiple records represents a single itemset. Hence, our vertical layout is similar to the popular layout used for the transaction table, which is the input of frequent itemset discovery. Our approach is particularly beneficial if the database system in use provides adequate strategies and techniques for processing universally quantified queries, unlike current commercial systems.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-05&engl=1} } @inproceedings {INPROC-2002-03, author = {Carmen Constantinescu and Uwe Heinkel and Ralf Rantzau and Bernhard Mitschang}, title = {{A System for Data Change Propagation in Heterogeneous Information Systems}}, booktitle = {Proceedings of the International Conference on Enterprise Information Systems (ICEIS), Volume I, Cuidad Real, Spain, April 2002}, publisher = {ICEIS Press/Escola Superior de Technologia de Setubal, Portugal}, institution = {University of Stuttgart, Faculty of Computer Science, Germany}, pages = {73--80}, type = {Conference Paper}, month = {April}, year = {2002}, keywords = {enterprise application integration; manufacturing; repository; propagation}, language = {English}, cr-category = {H.3.4 Information Storage and Retrieval Systems and Software}, ee = {http://www.iceis.org}, contact = {carmen.constantinescu@informatik.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Applications of Parallel and Distributed Systems}, abstract = {Today, it is common that enterprises manage several mostly heterogeneous information systems to supply their production and business processes with data. There is a need to exchange data between the information systems while preserving system autonomy. Hence, an integration approach that relies on a single global en-terprise data schema is ruled out. This is also due to the widespread usage of legacy systems. We propose a system, called Propagation Manager, which manages dependencies between data objects stored in different information systems. A script specifying complex data transformations and other sophisticated activities, like the execution of external programs, is associated with each dependency. For example, an object update in a source system can trigger data transformations of the given source data for each destination system that depends on the object. Our system is implemented using current XML technologies. We present the archi-tecture and processing model of our system and demonstrate the benefit of our approach by illustrating an extensive example scenario.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-03&engl=1} } @inproceedings {INPROC-2002-01, author = {Ralf Rantzau and Leonard Shapiro and Bernhard Mitschang and Quan Wang}, title = {{Universal Quantification in Relational Databases: A Classification of Data and Algorithms}}, booktitle = {Proceedings of the International Conference on Extending Database Technology (EDBT), Prague, Czech Republic, March 2002}, publisher = {Springer}, institution = {University of Stuttgart, Faculty of Computer Science, Germany}, series = {Lecture Notes in Computer Science}, volume = {2287}, pages = {445--463}, type = {Conference Paper}, month = {March}, year = {2002}, isbn = {3-540-43324-4}, keywords = {query processing; relational division; physical operators}, language = {English}, cr-category = {H.2.4 Database Management Systems}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2002-01/INPROC-2002-01.ps, http://www.springer.de/comp/lncs/index.html}, contact = {rrantzau@acm.org}, department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Applications of Parallel and Distributed Systems}, abstract = {Queries containing universal quantification are used in many applications, including business intelligence applications. Several algorithms have been proposed to implement universal quantification efficiently. These algorithms are presented in an isolated manner in the research literature - typically, no relationships are shown between them. Furthermore, each of these algorithms claims to be superior to others, but in fact each algorithm has optimal performance only for certain types of input data. In this paper, we present a comprehensive survey of the structure and performance of algorithms for universal quantification. We introduce a framework for classifying all possible kinds of input data for universal quantification. Then we go on to identify the most efficient algorithm for each such class. One of the input data classes has not been covered so far. For this class, we propose several new algorithms. For the first time, we are able to identify the optimal algorithm to use for any given input dataset. These two classifications of input data and optimal algorithms are important for query optimization. They allow a query optimizer to make the best selection when optimizing at intermediate steps for the quantification problem.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2002-01&engl=1} } @article {ART-2002-08, author = {Bernhard Mitschang and Aiko Frank}, title = {{A customizable shared information space to support concurrent design}}, journal = {Special Issue of Computers in Industry}, address = {Amsterdam}, publisher = {Elsevier Science Publishers B. V.}, volume = {48}, number = {1}, pages = {45--58}, type = {Article in Journal}, month = {May}, year = {2002}, issn = {0166-3615}, language = {English}, cr-category = {H.2.2 Database Management Physical Design}, contact = {Bernhard.Mitschang@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Sharing data is an important aspect in distributed design environments and should be supported by an underlying system. Any synchronous access to data is conflict prone. Applying concurrency control and two phase commit are one option to be considered. But design processes also demand for cooperation between the designers. Negotiation about actions on the product under design and the early exchange of preliminary results are crucial issues. Controlled data access by itself does not fulfil all the needs for cooperation. We will present a new approach that relies on a concept and system model which integrates concurrent activities by a joint information space offering flexible protocols for cooperation on the shared objects. We will describe the customizability of the protocols to effectively support different cooperative scenarios.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2002-08&engl=1} } @article {ART-2002-03, author = {Steffen (ifp) Volz and Matthias Gro{\ss}mann and Nicola H{\"o}nle and Daniela Nicklas and Thomas Schwarz}, title = {{Integration mehrfach repr{\"a}sentierter Stra{\ss}enverkehrsdaten f{\"u}r eine f{\"o}derierte Navigation}}, journal = {it+ti}, publisher = {Oldenbourg Verlag}, volume = {44}, number = {5}, pages = {260--267}, type = {Article in Journal}, month = {October}, year = {2002}, keywords = {Mobile Computing; Augmented World Model; GDF; ATKIS}, language = {German}, cr-category = {H.3.4 Information Storage and Retrieval Systems and Software, H.2.1 Database Management Logical Design}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2002-03/ART-2002-03.pdf, http://www.nexus.uni-stuttgart.de, http://www.it-ti.de}, contact = {steffen.volz@ifp.uni-stuttgart.de, matthias.grossmann@informatik.uni-stuttgart.de, nicola.hoenle@informatik.uni-stuttgart.de, daniela.nicklas@informatik.uni-stuttgart.de, thomas.schwarz@informatik.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed High-Performance Systems, Applications of Parallel and Distributed Systems; Universit{\"a}t Stuttgart, Institut f{\"u}r Photogrammetrie (ifp)}, abstract = {Die Forschergruppe Nexus entwickelt eine offene, verteilte Plattform f{\"u}r Anwendungen mit Ortsbezug. Dieser Artikel beschreibt, wie Strassenverkehrsdaten aus unterschiedlichen Quellen in das gemeinsame Datenmodell der Plattform integriert werden k{\"o}nnen, um Navigationsanwendungen zu erm{\"o}glichen. Die Abbildung mehrfach repr{\"a}sentierter Daten in einem einheitlichen Schema ist notwendig, um Anfragen auf Quellen zu verteilen, die Ergebnisse zusammenzufassen und so bestehende Daten weiter nutzen zu k{\"o}nnen.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2002-03&engl=1} }