Situation Aware Mobile Access to Digital Libraries - Semantic Scholar

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Fraunhofer Institute for Computer Graphics, 18059 Rostock, Germany. 2 current affiliation. IBM Silicon Valley Labs, 555 Bailey Ave, CA 95141 San Jose, USA.
Situation Aware Mobile Access to Digital Libraries Peter Haase 1

Database Research Group, Department of Computer Science University of Rostock, 18051 Rostock, Germany in cooperation with Fraunhofer Institute for Computer Graphics, 18059 Rostock, Germany 2 current affiliation IBM Silicon Valley Labs, 555 Bailey Ave, CA 95141 San Jose, USA [email protected]

Abstract. A conference and exhibition guide has been implemented to demonstrate how context information can be exploited to proactively provide situation relevant information in mobile environments. Different mobile devices, a wireless LAN and sensor technology provide the infrastructure for the situation aware mobile access to the Digital Library. Ontology based knowledge representation and reasoning are used to model the content of the Digital Library and user context and to determine situation relevant content.

Introduction Using state of the art mobile computing technology – ultraportable devices and wireless networks – it is possible to access any information at almost any place and any time. But considering the rapidly growing amounts of digital content, the following question gains importance: How do I find the right information at the right place and the right time. Specifically in mobile environments, lengthy interaction sequences to find the right information are not acceptable. Exploiting context information, i.e. information about the situation of the user and its surroundings, human computer interaction can be enriched by proactively providing situation relevant information. In the scientific context, often Digital Libraries are used for managing digital content such as conference proceedings, technical reports, lecture notes, etc. In the scope of a master’s thesis a system architecture for “Situation Aware Mobile Access to Digital Libraries” has been developed [Haa01]. In the demonstration an intelligent conference and exhibition guide based on this architecture will be presented. A notebook and a PocketPC as well as sensor and wireless technology are used to demonstrate how contextual information can be exploitated for the access to a Digital Library. The work is situated in the context of the Digital Library project BlueView [HMTP00] and a framework for Situation Aware Mobile Assistance, SaMOA [KCI98].

MoBible MoBible, the prototype of a conference and exhibition guide, is able to provide situation relevent content. For example, it suggests events to attend based on the interests and C.S. Jensen et al. (Eds.): EDBT 2002, LNCS 2287, pp. 772–774, 2002. c Springer-Verlag Berlin Heidelberg 2002 

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background of the user. On entering a conference room, lecture notes are displayed instantly. When approaching exponats of particular interest to the user, information is provided as well. All documents are presented in a format that matches the capabilities of the device in use. The system architecture consists of a stationary server and mobile devices to access the content of the Digital Library. To ensure an efficient, fault tolerant access, the architecture makes use of the following concepts: – Distributed data management: Using caching and replication techniques, the client holds a local copy of relevant data. Depending on network availability, information will be queried and retrieved transparently from either the server or the local copy on the mobile device. Different versions of IBM’s DB2 are used for data management: DB2 Everyplace on the mobile devices, DB2 UDB on the server side. – Level of Detail: This concept allows to provide only as much information as currently required. When relevant documents are suggested, initially only very condensed information, e.g. the title of a document, will be shown. On demand, more detailed information including an abstract will be presented. Finally, if requested, the full content, e.g. a PDF document or a Powerpoint presentation, will be displayed. The system has been implemented entirely in Java, therefore ensuring platform independence. For the demonstration, a PocketPC and a notebook are used as mobile devices. A wireless LAN is utilized for client-server communication.

Context Awareness To proactively provide relevant information it is necessary to discover and take advantage of contextual information. The MoBible system uses the following types of contextual information: – Physical environment: Obviously, location is one important aspect of the physical context. Objects in the proximity of the user are another aspect. – User tasks: Knowing the current activities of the user, it is possible to provide task relevant information. Typical tasks at conferences and exhibitions are for example attending events, scheduling meetings and obtaining information about exponats. – User profiles: These include for example interests and expertise of the user. – Device in use: The capabilities of mobile devices span a wide range. Obviously, information is valuable only if the device in use is able to display it. To discover certain contextual information, sensor technology can be utilized. For example, to determine the current position and objects in the proximity the system uses infrared technology. IrDA-BeaconsT M [Ide00], developed by the Fraunhofer Institute for Computer Graphics, identify objects and locations.

Ontology-Based Knowledge Representation and Reasoning For the modelling of the user situation and the content of the Digital Library, techniques from ontology-based knowledge representation have been used. This allows to enrich the available information with machine-processable semantics.

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The ontology has been expressed in DAML [vHa01], an evolving standard of the Semantic Web community based on the W3C standards RDF and XML. DAML offers rich modelling capabilities, allows for interoperability on a semantic level, and provides reasoning support. The facts of the knowledge base can be used in an inference engine to automatically reason about situation relevant information. In the implemented system an inference engine based on Frame-Logic – a rule-based, deductive query and inference language [DBSA] – has been used.

Summary The MoBible system demonstrates that with today’s technology it is possible to develop mobile intelligent assistants that allow situation aware access to content in Digital Libraries. The conference and exhibition guide is only one example where contextual information can be used to proactively relevant content. In contrast to existing solutions, this system supports a wide range of mobile devices. Moreover, it does not require a permanent network connection, since relevant information is replicated and processed locally on the mobile device.

References DBSA.

Haa01. HMTP00.

Ide00.

KCI98.

vHa01.

Stefan Decker, Dan Brickley, Janne Saarela, and J¨urgen Angele. A Query and Inference Service for RDF. http://www.w3.org/TandS/QL/QL98/pp/ queryservice.html Peter Haase. Situationsgesteuerter mobiler Zugriff auf Digitale Bibliotheken. Master’s thesis, University of Rostock, Germany, 2001 Andreas Heuer, Holger Meyer, Patrick Titzler, and Beate Porst. BlueView: Virtual Document Servers for Digital Libraries. In Proceedings of the IEEE Conference on Advances in Digital Libraries, 2000. http://wwwdb.informatik.unirostock.de/blueview/paper/adl00.pdf R¨udiger Ide. IrDA Beacon (TM) Transmitter, 2000. http://www.rostock.igd.fhg.de/fhg igd/abteilungen/a3/ projects/irda/ Thomas Kirste, Esteban Chavez, and R¨udiger Ide. SAMoA: An experimental platform for Situation-Aware Mobile Assistance. In Proceedings of the Workshop IMC 98, pages 29–36, 1998. http://www.rostock.igd.fhg.de/ fhg igd/abteilungen/a3/files/pdf/imc98-samoa.pdf Frank van Harmelen, Peter F. Patel-Schneider, and Ian Horrocks. Reference description of the DAML+OIL (March 2001) ontology markup language, 2001. http://www.daml.org/2001/03/reference.html