@inproceedings {INPROC-2009-94, author = {Nazario Cipriani and Mike Eissele and Andreas Brodt and Matthias Gro{\ss}mann and Bernhard Mitschang}, title = {{NexusDS: A Flexible and Extensible Middleware for Distributed Stream Processing}}, booktitle = {IDEAS '09: Proceedings of the 2008 International Symposium on Database Engineering \& Applications}, editor = {ACM}, publisher = {ACM}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, pages = {152--161}, type = {Conference Paper}, month = {September}, year = {2009}, keywords = {Data Stream Processing; Stream Databases; Middleware Platforms for DataManagement; P2P and Networked DataManagement; Database Services and Applications}, language = {English}, cr-category = {C.2 Computer-Communication Networks, C.5 Computer System Implementation, H.2 Database Management}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {ABSTRACT Techniques for efficient and distributed processing of huge, unbound data streams have made some impact in the database community. Sensors and data sources, such as position data of moving objects, continuously produce data that is consumed, e.g., by location-aware applications. Depending on the domain of interest, e.g. visualization, the processing of such data often depends on domain-specific functionality. This functionality is specified in terms of dedicated operators that may require specialized hardware, e.g. GPUs. This creates a strong dependency which a data stream processing system must consider when deploying such operators. Many data stream processing systems have been presented so far. However, these systems assume homogeneous computing nodes, do not consider operator deployment constraints, and are not designed to address domain-specific needs. In this paper, we identify necessary features that a exible and extensible middleware for distributed stream processing of context data must satisfy. We present NexusDS, our approach to achieve these requirements. In NexusDS, data processing is specified by orchestrating data flow graphs, which are modeled as processing pipelines of predefined and general operators as well as custom-built and domain-specific ones. We focus on easy extensibility and support for domain-specific operators and services that may even utilize specific hardware available on dedicated computing nodes}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-94&engl=1} } @inproceedings {INPROC-2009-86, author = {Matthias Grossmann and Nicola H{\"o}nle and Carlos L{\"u}bbe and Harald Weinschrott}, title = {{An Abstract Processing Model for the Quality of Context Data}}, booktitle = {Proceedings of the 1st International Workshop on Quality of Context}, publisher = {Springer}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, pages = {132--143}, type = {Workshop Paper}, month = {June}, year = {2009}, keywords = {uncertainty; inconsistency; trust; processing model}, language = {English}, cr-category = {H.2.8 Database Applications}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2009-86/INPROC-2009-86.pdf, http://dx.doi.org/10.1007/978-3-642-04559-2_12}, contact = {Matthias.Grossmann@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems; University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Data quality can be relevant to many applications. Especially applications coping with sensor data cannot take a single sensor value for granted. Because of technical and physical restrictions each sensor reading is associated with an uncertainty. To improve quality, an application can combine data values from different sensors or, more generally, data providers. But as different data providers may have diverse opinions about a certain real world phenomenon, another issue arises: inconsistency. When handling data from different data providers, the application needs to consider their trustworthiness. This naturally introduces a third aspect of quality: trust. In this paper we propose a novel processing model integrating the three aspects of quality: uncertainty, inconsistency and trust.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-86&engl=1} } @inproceedings {INPROC-2009-68, author = {Sylvia Radesch{\"u}tz and Bernhard Mitschang}, title = {{Extended Analysis Techniques For a Comprehensive Business Process Optimization}}, booktitle = {Proc. of the International Conference on Knowledge Management and Information Sharing (KMIS 2009), Portugal, 6.-8. Oktober, 2009.}, publisher = {Springer}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {1--6}, type = {Conference Paper}, month = {October}, year = {2009}, language = {English}, cr-category = {H.2.7 Database Administration, H.2.8 Database Applications}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Efficient adaption of a company’s business and its business processes to a changing environment is a crucial ability to survive in today’s dynamic world. For optimizing business processes, a profound analysis of all relevant business data in the company is necessary. We define an extended data warehouse approach that integrates process-related data and operational business data. This extended data warehouse is used as the underlying data source for extended OLAP and data mining analysis techniques for a comprehensive business process optimization.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-68&engl=1} } @inproceedings {INPROC-2009-60, author = {Andreas Brodt and Christoph Stach}, title = {{Mobile ortsbasierte Browserspiele}}, booktitle = {Tagungsband der 39. GI-Jahrestagung, 28.9. - 2.10.2009, Universit{\"a}t zu L{\"u}beck}, editor = {Gesellschaft f{\"u}r Informatik e.V.}, publisher = {Gesellschaft f{\"u}r Informatik e.V. (GI)}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, series = {Lecture Notes in Informatics}, type = {Workshop Paper}, month = {September}, year = {2009}, keywords = {Pervasive Games; GPS; location-based games; browser games}, language = {German}, cr-category = {H.5.1 Multimedia Information Systems, H.5.2 Information Interfaces and Presentation User Interfaces, K.8 Personal Computing}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2009-60/INPROC-2009-60.pdf}, contact = {Andreas Brodt andreas.brodt@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Die Verbreitung von mobilen Ger{\"a}ten und Positionssensoren wie GPS erm{\"o}glicht mobile ortsbasierte Spiele, in denen sich die Spieler physisch in ihrer Umwelt bewegen m{\"u}ssen, um Einfluss auf das Spielgeschehen zu nehmen. Klassische Computerspiele werden zunehmend als Browserspiel realisiert, d.h. der Web-Browser des Spielers wird f{\"u}r die Benutzerschnittstelle verwendet. Indem der Web-Browser um eine Kontextschnittstelle erweitert wird, kann einem Browserspiel Zugriff auf die aktuelle Position des Spielers gew{\"a}hrt werden. Dadurch wird es m{\"o}glich, mobile ortsbasierte Spiele im Web-Browser zu spielen. In diesem Papier besch{\"a}ftigen wir uns mit dem Eigenschaften mobiler ortsbasierter Browserspiele. Wir stellen zwei Beispiele vor, anhand derer wir untersuchen, welche Einfl{\"u}sse mobile ortsbasierte Spiele auf das Spielkonzept haben und welche technischen Konsequenzen sich daraus ergeben. Abschlie{\ss}end pr{\"a}sentieren wir ein Framework zur Entwicklung mobiler ortsbasierter Spiele.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-60&engl=1} } @inproceedings {INPROC-2009-53, author = {Nazario Cipriani and Matthias Wieland and Matthias Grossmann and Daniela Nicklas}, title = {{Tool Support for the Design and Management of Spatial Context Models}}, booktitle = {Proc. of the 13th East European Conference on Advances in Databases and Information Systems (ADBIS 2009)}, address = {Riga, Lativa}, publisher = {Springer}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, type = {Conference Paper}, month = {September}, year = {2009}, language = {English}, cr-category = {H.2.4 Database Management Systems}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems; University of Stuttgart, Institute of Architecture of Application Systems}, abstract = {A central task in the development of context-aware applications is the modeling and management of complex context information. In this paper, we present the NexusEditor, which eases this task by providing a graphical user interface to design schemas for spatial context models, interactively create queries, send them to a server and visualize the results. One main contribution is to show how schema awareness can improve such a tool: the NexusEditor dynamically parses the underlying data model and provides additional syntactic checks, semantic checks, and short-cuts based on the schema information. Furthermore, the tool helps to design new schema definitions based on the existing ones, which is crucial for an iterative and user-centric development of context-aware applications. Finally, it provides interfaces to existing information spaces and visualization tools for spatial data like GoogleEarth.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-53&engl=1} } @inproceedings {INPROC-2009-47, author = {Andreas Brodt and Sailesh Sathish}, title = {{Together we are strong -- Towards ad-hoc smart spaces}}, booktitle = {Proceedings of the 7th Annual IEEE International Conference on Pervasive Computing and Communications (PerCom '09). Galveston, TX, USA. March 2009}, publisher = {IEEE Computer Society}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, pages = {1--4}, type = {Conference Paper}, month = {January}, year = {2009}, keywords = {ad-hoc; smart space; mobile}, language = {English}, cr-category = {H.2.8 Database Applications, H.3.4 Information Storage and Retrieval Systems and Software, H.3.5 Online Information Services}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2009-47/INPROC-2009-47.pdf, http://www.nexus.uni-stuttgart.de/}, contact = {andreas.brodt@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Today's mobile devices feature many resources, sensors and data, which make it possible for them to adapt to their environment. However, they would have a lot more resources at hand, and thus could better adapt to their context, if they used their communication capabilities to share their resources with others near them. In this paper we propose the concept of ad-hoc smart spaces, which enables mobile devices to utilize resources owned by other devices in physical proximity. This imposes a number of challenges as cooperation partners can join and leave any time and as devices are highly heterogeneous. We propose a system architecture for ad-hoc smart spaces and present a prototypic implementation.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-47&engl=1} } @inproceedings {INPROC-2009-46, author = {Eva Fenrich and Andreas Brodt and Daniela Nicklas}, title = {{WODCA: A MOBILE, WEB-BASED FIELD SAMPLING SUPPORT SYSTEM}}, booktitle = {Proceedings of the 8th international conference on Hydroinformatics, HEIC 2009}, publisher = {International Water Association}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, pages = {1--10}, type = {Conference Paper}, month = {January}, year = {2009}, keywords = {GPS, DCCI, Field sampling,}, language = {English}, cr-category = {H.3.5 Online Information Services}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Efficient data acquisition methods can save time and money in field measurements. As most field data in aquatic systems is time dependent, it is important to minimize sampling errors as measurements for a certain time and place cannot be re-taken. For larger measurement campaigns with different teams at distributed sampling sites, information about data from other teams as well as environmental data like gauge, tidal or upstream weather information could help to interpret measurement results already on site. We propose WODCA (Water Observation Data Collecting Application), a mobile, online measurement support system. The measurements are sent wirelessly to a geographic database that provides back an integrated view on already taken measurements of all mobile parties, augmented with online environmental data like gauge data or tidal information. This eases the collaboration between different mobile measurement teams. GPS integration and map based data input can help to avoid location errors. The proposed system could assist materially in the improvement of field data quality and sampling comfort.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-46&engl=1} } @inproceedings {INPROC-2009-45, author = {Andreas Brodt and Nazario Cipriani}, title = {{NexusWeb - eine kontextbasierte Webanwendung im World Wide Space}}, booktitle = {Datenbanksysteme in Business, Technologie und Web (BTW 2009), 13. Fachtagung des GI-Fachbereichs ``Datenbanken und Informationssysteme'' (DBIS), Proceedings, 2.-6. M{\"a}rz 2009, M{\"u}nster, Germany}, editor = {GI}, publisher = {GI}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, series = {Lecture Notes in Informatics}, volume = {144}, pages = {588--591}, type = {Conference Paper}, month = {March}, year = {2009}, isbn = {978-3-88579-238-3}, keywords = {DCCI, location-based services, Nokia N810, Internet Tablet, GPS, Google Maps, Nexus, AWQL, AWML}, language = {German}, cr-category = {H.3.5 Online Information Services}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2009-45/INPROC-2009-45.pdf}, contact = {Andreas Brodt andreas.brodt@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Wir pr{\"a}sentieren NexusWeb, eine kontextbasierte Webanwendung, die ein Umgebungsmodell des Benutzers zeichnet. NexusWeb bezieht dazu Kontextdaten des World Wide Space, einer F{\"o}deration verschiedenster Datenanbieter. Die GPS-Position des Benutzers gelangt {\"u}ber eine standardisierte Browsererweiterung in die Webanwendung und steuert die Ansicht von NexusWeb. Wir zeigen verschiedene Szenarien sowohl auf einem mobilen Ger{\"a}t als auch auf einem gew{\"o}hnlichen Laptop.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-45&engl=1} } @inproceedings {INPROC-2009-29, author = {Fabian Kaiser and Holger Schwarz and Mih{\'a}ly Jakob}, title = {{Using Wikipedia-based conceptual contexts to calculate document similarity}}, booktitle = {ICDS2009: Proceedings of the 3rd International Conference on Digital Society}, address = {Cancun, Mexico}, publisher = {IEEE Computer Society}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {322--327}, type = {Conference Paper}, month = {February}, year = {2009}, language = {English}, cr-category = {H.3 Information Storage and Retrieval, H.3.3 Information Search and Retrieval}, ee = {http://dx.doi.org/10.1109/ICDS.2009.7}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Rating the similarity of two or more text documents is an essential task in information retrieval. For example, document similarity can be used to rank search engine results, cluster documents according to topics etc. A major challenge in calculating document similarity originates from the fact that two documents can have the same topic or even mean the same, while they use different wording to describe the content. A sophisticated algorithm therefore will not directly operate on the texts but will have to find a more abstract representation that captures the texts' meaning. In this paper, we propose a novel approach for calculating the similarity of text documents. It builds on conceptual contexts that are derived from content and structure of the Wikipedia hypertext corpus.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-29&engl=1} } @inproceedings {INPROC-2009-130, author = {Jorge Minguez and Mihaly Jakob and Uwe Heinkel and Bernhard Mitschang}, title = {{A SOA-based approach for the integration of a data propagation system}}, booktitle = {IRI'09: Proceedings of the 10th IEEE international conference on Information Reuse \& Integration}, publisher = {IEEE Press}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {47--52}, type = {Conference Paper}, month = {August}, year = {2009}, isbn = {978-1-4244-4114-3}, language = {German}, cr-category = {D.2.11 Software Engineering Software Architectures, D.2.13 Software Engineering Reusable Software}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Major challenges that companies face nowadays are extremely volatile markets, a globally distributed supplier network and constantly changing business environments. These circumstances demand a high level of agility and extraordinary flexibility in the business modeling and the organizational structures of a company as well as adaptive and interoperable IT systems. In order to meet these requirements an integration of systems needs to be achieved. A possible solution for this problem is Champagne, which is a data propagation system that ensures the interoperability of enterprise applications at the data level. However, Champagne provides a tightly-coupled integration of applications and its architecture lacks the needed flexibility to link business processes. These deficiencies can be overcome with the adoption of a service-oriented architecture (SOA), based on loosely-coupled services, which enable a higher level of flexibility and interoperability. Therefore, we explore in this paper a number of options to reuse and integrate Champagne into a service-oriented architecture in order to benefit from SOA principles.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-130&engl=1} } @inproceedings {INPROC-2009-126, author = {Jorge M$\backslash$'$\backslash$inguez and Mih$\backslash$'aly Jakob and Uwe Heinkel and Bernhard Mitschang}, title = {{A SOA-based approach for the integration of a data propagation system}}, booktitle = {IRI'09: Proceedings of the 10th IEEE international conference on Information Reuse \& Integration}, publisher = {IEEE Press}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {47--52}, type = {Conference Paper}, month = {August}, year = {2009}, isbn = {978-1-4244-4114-3}, language = {English}, cr-category = {D.2.11 Software Engineering Software Architectures, D.2.13 Software Engineering Reusable Software}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Major challenges that companies face nowadays are extremely volatile markets, a globally distributed supplier network and constantly changing business environments. These circumstances demand a high level of agility and extraordinary flexibility in the business modeling and the organizational structures of a company as well as adaptive and interoperable IT systems. In order to meet these requirements an integration of systems needs to be achieved. A possible solution for this problem is Champagne, which is a data propagation system that ensures the interoperability of enterprise applications at the data level. However, Champagne provides a tightly-coupled integration of applications and its architecture lacks the needed flexibility to link business processes. These deficiencies can be overcome with the adoption of a service-oriented architecture (SOA), based on loosely-coupled services, which enable a higher level of flexibility and interoperability. Therefore, we explore in this paper a number of options to reuse and integrate Champagne into a service-oriented architecture in order to benefit from SOA principles.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-126&engl=1} } @inproceedings {INPROC-2009-125, author = {Jorge M$\backslash$'$\backslash$inguez and Mih$\backslash$'aly Jakob and Uwe Heinkel and Bernhard Mitschang}, title = {{A SOA-based approach for the integration of a data propagation system}}, booktitle = {IRI'09: Proceedings of the 10th IEEE international conference on Information Reuse \& Integration}, publisher = {IEEE Press}, institution = {University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology, Germany}, pages = {47--52}, type = {Conference Paper}, month = {August}, year = {2009}, isbn = {978-1-4244-4114-3}, language = {English}, cr-category = {D.2.11 Software Engineering Software Architectures, D.2.13 Software Engineering Reusable Software}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Major challenges that companies face nowadays are extremely volatile markets, a globally distributed supplier network and constantly changing business environments. These circumstances demand a high level of agility and extraordinary flexibility in the business modeling and the organizational structures of a company as well as adaptive and interoperable IT systems. In order to meet these requirements an integration of systems needs to be achieved. A possible solution for this problem is Champagne, which is a data propagation system that ensures the interoperability of enterprise applications at the data level. However, Champagne provides a tightly-coupled integration of applications and its architecture lacks the needed flexibility to link business processes. These deficiencies can be overcome with the adoption of a service-oriented architecture (SOA), based on loosely-coupled services, which enable a higher level of flexibility and interoperability. Therefore, we explore in this paper a number of options to reuse and integrate Champagne into a service-oriented architecture in order to benefit from SOA principles.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-125&engl=1} } @inproceedings {INPROC-2009-120, author = {Nicola H{\"o}nle and Matthias Gro{\ss}mann and Dominik Lucke and Engelbert Westk{\"a}mper}, title = {{Historisierung und Analyse von Stromdaten in einem Data Warehouse am Beispiel der Smart Factory}}, booktitle = {Beitr{\"a}ge der 39. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI)}, editor = {Stefan Fischer and Erik Maehle and R{\"u}diger Reischuk}, address = {Bonn}, publisher = {Gesellschaft f{\"u}r Informatik e.V. (GI)}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, series = {Lecture Notes in Informatics}, volume = {P-154}, pages = {246--246}, type = {Workshop Paper}, month = {September}, year = {2009}, isbn = {978-3-88579-248-2}, language = {German}, cr-category = {H.2.8 Database Applications, J.7 Computers in Other Systems}, department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Industrielle Fertigung und Fabrikbetrieb (IFF); University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Die heute geforderte schnelle Anpassung von Fabriken an sich st{\"a}ndig {\"a}ndernde Herausforderungen des Marktes erfordert aktuelle und korrekte Informationen {\"u}ber den Zustand der Fabrik. Dabei fallen Stromdaten unterschiedlicher Herkunft an (z.B. Betriebsdaten aus Maschinen oder Sensormesswerte, verkn{\"u}pft mit virtuellen Informationen wie z.B. Workflows), zu deren Erfassung und Integration ein System zum Stromdatenmanagement ben{\"o}tigt wird. Dazu setzen wir ein spezielles Datenstromverarbeitungssystem ein. Im Teilprojekt „Smart Factory“ des Sonderforschungsbereichs 627 Nexus werden Anwendungen f{\"u}r die Produktion erforscht, die eine kontextbezogene Unterst{\"u}t-zung von Mitarbeitern und Maschinen erm{\"o}glichen. Die anfallenden Daten in der Smart Factory sowohl von Sensoren als auch von Leitrechnern und Maschinen k{\"o}nnen nicht nur zur Unterst{\"u}tzung aktueller Aufgaben verwendet werden, sondern aus der Analyse der Datenhistorien lassen sich auch wertvolle Erkenntnisse gewinnen, die wiederum r{\"u}ckwirkend den Alltagsbetrieb in der Fabrik verbessern k{\"o}nnen. In diesem Artikel stellen wir den Entwurf eines Data Warehouses vor, das zur Speicherung und Analyse von Datenhistorien aus der Smart Factory entworfen wurde, und wir skizzieren, wie mit Hilfe des verwendeten Datenstromverarbeitungssystems das kontinuierliche Laden der Daten realisiert werden kann.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-120&engl=1} } @inproceedings {INPROC-2009-119, author = {Nazario Cipriani and Carlos L{\"u}bbe}, title = {{Ausnutzung von Restriktionen zur Verbesserung des Deployment-Vorgangs des Verteilten Datenstromverarbeitungssystems NexusDS}}, booktitle = {Beitr{\"a}ge der 39. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI)}, editor = {Stefan Fischer and Erik Maehle and R{\"u}diger Reischug}, address = {Bonn}, publisher = {Gesellschaft f{\"u}r Informatik e.V. (GI)}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, series = {Lecture Notes in Informatics}, volume = {P-154}, pages = {240--240}, type = {Workshop Paper}, month = {September}, year = {2009}, isbn = {978-3-88579-248-2}, keywords = {Data Stream Processing; Stream Databases; Middleware Platforms for Data Management; P2P and Networked Data Management; Database Services and Applications}, language = {German}, cr-category = {C.2 Computer-Communication Networks, H.2 Database Management}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Kontextsensitive Informationssysteme verarbeiten h{\"a}ufig Daten der n{\"a}heren Umgebung, die mit Hilfe von Sensoren kontinuierlich erhoben werden. F{\"u}r die Verarbeitung kontinuierlicher Datenstr{\"o}me k{\"o}nnen Datenstromverarbeitungssysteme eingesetzt werden. Jedoch m{\"u}ssen diese im Bereich der Kontextdatenverarbeitung mit einem heterogenen Umfeld zurechtkommen. Je nach technischer Ausstattung der physischen Umgebung sollten sie sich an die dort geltenden Bedingungen bzw. Restriktionen anpassen. F{\"u}r verteilte Datenstromverarbeitungssysteme ist die Anfrageverteilung in einem solchen Umfeld eine besondere Herausforderung, denn das System muss Restriktionen auf verschiedenen Ebenen ber{\"u}cksichtigen. So k{\"o}nnte ein Teil der Anfrage gewisse Anforderungen an seine Ausf{\"u}hrungsumgebung haben, wie spezialisierte Hardware, oder es k{\"o}nnte aus Sicherheitsgr{\"u}nden notwendig sein, die Anfrage oder einen Anfrageteil in einer sicheren Ausf{\"u}hrungsumgebung auszuf{\"u}hren. In diesem Papier klassifizieren wir Restriktionen, die auf verschiedenen Ebenen der Anfrageverarbeitung des Systems vorkommen k{\"o}nnen. {\"U}berdies stellen wir ein Konzept zur Modellierung der Restriktionsklassen vor und zeigen wie diese in der Anfrageverarbeitung des verteilten Datenstromverarbeitungssystems NexusDS ber{\"u}cksichtigt werden.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-119&engl=1} } @inproceedings {INPROC-2009-07, author = {Ralph Lange and Nazario Cipriani and Lars Geiger and Matthias Gro{\ss}mann and Harald Weinschrott and Andreas Brodt and Matthias Wieland and Stamatia Rizou and Kurt Rothermel}, title = {{Making the World Wide Space Happen: New Challenges for the Nexus Context Platform}}, booktitle = {Proceedings of the 7th Annual IEEE International Conference on Pervasive Computing and Communications (PerCom '09). Galveston, TX, USA. March 2009}, publisher = {IEEE Computer Society}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, pages = {1--4}, type = {Conference Paper}, month = {March}, year = {2009}, keywords = {Nexus; context; mobile context-aware applications; context-awareness; context management; World Wide Space; stream-processing; situation recognition; reasoning; workflows; quality of context}, language = {English}, cr-category = {H.2.8 Database Applications, H.3.4 Information Storage and Retrieval Systems and Software, H.3.5 Online Information Services}, ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2009-07/INPROC-2009-07.pdf, http://www.nexus.uni-stuttgart.de/, http://dx.doi.org/10.1109/PERCOM.2009.4912782}, contact = {ralph.lange@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems; University of Stuttgart, Institute of Architecture of Application Systems; University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Context-aware applications rely on models of the physical world. Within the Nexus project, we envision a World Wide Space which provides the conceptual and technological framework for integrating and sharing such context models in an open, global platform of context providers. In our ongoing research we tackle important challenges in such a platform including distributed processing of streamed context data, situation recognition by distributed reasoning, efficient management of context data histories, and quality of context information. In this paper we discuss our approach to cope with these challenges and present an extended Nexus architecture.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-07&engl=1} } @article {ART-2009-30, author = {Nicola H{\"o}nle and Matthias Grossmann and Daniela Nicklas and Bernhard Mitschang}, title = {{Design and implementation of a domain-aware data model for pervasive context information}}, journal = {Computer Science Research + Development}, publisher = {Springer}, volume = {24}, number = {1-2}, pages = {69--83}, type = {Article in Journal}, month = {September}, year = {2009}, language = {English}, cr-category = {H.2.1 Database Management Logical Design, H.2.8 Database Applications}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {We introduce a data model for a context-management middleware that enables context-aware and pervasive computing applications to transparently access available data providers and that effectively combines their data. Our approach supports new data fusion concepts for overlapping and heterogeneous data sets and thus maximizes the information presented to the application. The main part of our data model is a flexible concept for meta data that is able to represent important aspects like quality, data derivation, or temporal characteristics of data. Attributes having multiple values are utilized to represent sensor measurements histories like locations of mobile objects at different points in time. In our paper, we characterize the requirements for our data model and show that existing data models, including the (object-) relational data model and standard XML data models, do not offer the required flexibility. Therefore basic XML technology is extended to support the necessary meta data concept and multiply typed objects.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2009-30&engl=1} } @article {ART-2009-09, author = {Jing Lu and Bernhard Mitschang}, title = {{Enforcing Data Consistency in Data Integration Systems by XQuery Trigger Service}}, journal = {International Journal of Web Information Systems}, publisher = {Emerald Group Publishing Limited}, volume = {5}, number = {2}, pages = {1--19}, type = {Article in Journal}, month = {May}, year = {2009}, language = {English}, cr-category = {E.0 Data General}, contact = {jinglu76@gmail.com}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Nowadays XML-based data integration systems are accepted as data service providers on the web. In order to make such a data integration system fully equipped with data manipulation capabilities, programming frameworks which support update at the integration level are being developed. When the user is permitted to submit updates, it is necessary to establish the best possible data consistency for the whole data integration system. To that extend, we present an approach based on an XQuery trigger service. We define an XQuery trigger model together with its semantics. We report on the integration of the XQuery trigger service into the overall architecture and discuss details of the execution model. Experiments show that our approach provides an easy, efficient and convenient way to achieve data consistency at the global level.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2009-09&engl=1} } @article {ART-2009-08, author = {Nazario Cipriani and Daniela Nicklas and Matthias Gro{\ss}mann and Nicola H{\"o}nle and Carlos L{\"u}bbe and Bernhard Mitschang}, title = {{Verteilte Datenstromverarbeitung von Sensordaten}}, journal = {Datenbank-Spektrum}, publisher = {dpunkt Verlag}, volume = {9}, number = {28}, pages = {37--43}, type = {Article in Journal}, month = {February}, year = {2009}, language = {German}, cr-category = {H.2.4 Database Management Systems, H.2.8 Database Applications, E.4 Data Coding and Information Theory}, contact = {nazario.cipriani@ipvs.uni-stuttgart.de}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Technologischer Fortschritt im Bereich der Mikroelektronik und Kommunikationstechnik f{\"u}hren zunehmend zu einem stark vernetzten, mit Sensoren ausgestatteten Umfeld. Die Herausforderung, die in diesem Zusammenhang auftretenden kontinuierlichen Datenstr{\"o}me zu verwalten und effizient zu verarbeiten, sowie heterogene Sensorger{\"a}te und Netztopologien zu integrieren, ist f{\"u}r viele Anwendungsentwickler eine zu gro{\ss}e H{\"u}rde. In dieser Arbeit wird eine Middleware vorgestellt, die es einer Anwendung erm{\"o}glicht, anfragebasiert die Verarbeitung von kontinuierlichen Datenstr{\"o}men zu steuern. Die zur Verarbeitung der Daten ben{\"o}tigten Operatoren werden virtualisiert ausgef{\"u}hrt, um die gr{\"o}{\ss}tm{\"o}gliche Flexibilit{\"a}t bei der Verteilung auf die beteiligten physischen Knoten zu erreichen. Weiterhin werden Ans{\"a}tze zur Komprimierung von Datenstr{\"o}men vorgestellt, um das Gesamtvolumen der ausgetauschten Daten zwischen den Knoten zu reduzieren.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2009-08&engl=1} } @article {ART-2009-03, author = {Daniela Nicklas and Matthias Grossmann and Matthias Wieland}, title = {{Context Modeling for Mobile, Adaptive Applications}}, journal = {it - Information Technology}, publisher = {Oldenbourg Wissenschaftsverlag GmbH}, volume = {51}, number = {2}, pages = {85--92}, type = {Article in Journal}, month = {March}, year = {2009}, doi = {10.1524/itit.2009.0527}, keywords = {ubiquitous Computing; pervasive Computing; context modeling; mobile applications; Content Analysis and indexing}, language = {English}, cr-category = {H.2.4 Database Management Systems, H.2.8 Database Applications, H.3 Information Storage and Retrieval}, ee = {http://www.atypon-link.com/OLD/toc/itit/51/2, http://www.atypon-link.com/OLD/doi/pdf/10.1524/itit.2009.0527}, department = {University of Stuttgart, Institute of Architecture of Application Systems; University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Abstract Context-aware applications adapt their behavior according to the current situation. In this paper we present a layered model to separate different tasks and concerns in designing data models for context-aware applications. The layers are discussed along the Nexus approach, which is designed to support large-scale, mobile applications by federated context models. Furthermore, related approaches are described and compared. Zusammenfassung Kontextbezogene Anwendungen adaptieren ihr Verhalten aufgrund von Situationen. Dieser Beitrag pr{\"a}sentiert ein Ebenenmodell f{\"u}r Datenmodelle solcher Anwendungen, das verschiedene Probleme und Aufgaben im Entwurf der Daten, der Adaptionslogik und der Verarbeitung kapselt. Die Ebenen werden anhand des Nexus-Ansatzes diskutiert, dessen Ziel es ist, mobile, kontext-bezogene Anwendungen durch f{\"o}derierte Kontextmodelle zu unterst{\"u}tzen, und mit verwandten Arbeiten verglichen.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2009-03&engl=1} } @inbook {INBOOK-2009-04, author = {Rodrigo Salvador Monteiro and Geraldo Zimbr{\~a}o and Jano Moreira de Souza and Holger Schwarz and Bernhard Mitschang}, title = {{Exploring Calendar-based Pattern Mining in Data Streams}}, series = {Complex Data Warehousing and Knowledge Discovery for Advanced Retrieval Development: Innovative Methods and Applications}, publisher = {IGI Global}, pages = {1--30}, type = {Article in Book}, month = {June}, year = {2009}, isbn = {978-1-60566-748-5}, language = {English}, cr-category = {H.2.8 Database Applications}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {Finally, Chapter XVI introduces a calendar-based pattern mining that aims at identifying patterns on specific calendar partitions in continuous data streams. The authors present how a data warehouse approach can be applied to leverage calendar-based pattern mining in data streams and how the framework of the DWFIST approach can cope with tight time constraints imposed by data streams, keep storage requirements at a manageable level and, at the same time, support calendar-based frequent itemset mining. The minimum granularity of analysis, parameters of the data warehouse (e.g. mining minimum support) and parameters of the database (e.g. extent size) provide ways to tune the load performance.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2009-04&engl=1} } @inbook {INBOOK-2009-01, author = {Cataldo Mega and Kathleen Krebs and Frank Wagner and Norbert Ritter and Bernhard Mitschang}, title = {{Content-Management-Systeme der n{\"a}chsten Generation}}, series = {Wissens- und Informationsmanagement ; Strategien, Organisation und Prozesse}, address = {Wiesbaden}, publisher = {Gabler Verlag}, pages = {539--567}, type = {Article in Book}, month = {January}, year = {2009}, isbn = {978-3-8349-0937-4}, language = {German}, cr-category = {H.3.2 Information Storage}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems}, abstract = {...}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2009-01&engl=1} } @proceedings {PROC-2009-02, editor = {Kurt Rothermel and Dieter Fritsch and Wolfgang Blochinger and Frank D{\"u}rr}, title = {{Quality of Context -- Proceedings of the First International Workshop on Quality of Context (QuaCon 2009)}}, address = {Stuttgart, Germany}, publisher = {Springer}, institution = {University of Stuttgart : Collaborative Research Center SFB 627 (Nexus: World Models for Mobile Context-Based Systems), Germany}, series = {Lecture Notes in Computer Science}, volume = {5786}, pages = {184}, type = {Proceedings}, month = {June}, year = {2009}, isbn = {978-3-642-04558-5}, keywords = {context-aware systems; location-based services; quality; context}, language = {English}, cr-category = {H.2.8 Database Applications, H.3.3 Information Search and Retrieval, H.3.5 Online Information Services}, department = {University of Stuttgart, Institute of Parallel and Distributed Systems, Applications of Parallel and Distributed Systems; Universit{\"a}t Stuttgart, Institut f{\"u}r Photogrammetrie (ifp); University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems; University of Stuttgart, Institute for Natural Language Processing}, abstract = {Advances in sensor technology, wireless communication, and mobile devices lead to the proliferation of sensors in our physical environment. At the same time detailed digital models of buildings, towns, or even the globe become widely available. Integrating the huge amount of sensor data into spatial models results in highly dynamic models of the real world, often called context models. A wide range of applications can substantially benefit from context models. However, context data are inherently associated with uncertainty. In general, quality of context information has to be taken into account by both context management and applications. For example, the accuracy, completeness, and trustworthiness of spatial context information such as street or building data are very important for navigation and guidance systems. QuaCon 2009 was the first international scientific meeting that specifically focused on the different aspects of quality of context data. Research in context management and, in particular, context quality, requires an interdisciplinary approach. Therefore, the QuaCon workshop aimed to bring together researchers from various fields to discuss approaches to context quality and to make a consolidated contribution toward an integrated way of treating this topic. We received 19 high-quality paper submissions by researchers from Europe, USA, and Asia. The International Program Committee selected 11 papers for presentation at the workshop. Additionally, five invited contributions by internationally renowned experts in the field were included in the workshop program. The presentations at the workshop showed many facets of quality of context from different research fields including context data management, spatial models, context reasoning, privacy, and system frameworks. The lively discussions underlined the great interest in this topic and in particular led to a deeper understanding of the relations between the various aspects of quality of context. The success of QuaCon 2009 was the result of a team effort. We are grateful to the members of the Program Committee and the external reviewers for their thorough and timely reviews as well as to the authors for their high-quality submissions and interesting talks. We would like to extend special thanks to our invited speakers for their excellent and inspiring keynotes. Finally, we wish to thank all persons involved in the organization of the QuaCon 2009 workshop who did really a great job.}, url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=PROC-2009-02&engl=1} }