Fraunhofer Institut für Integrierte Publikations-und Informationssysteme IPSI

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Efficient entity resolution for large heterogeneous information spaces

2011 , Papadakis, G. , Loannou, E. , Niederée, C. , Fankhauser, P.

We have recently witnessed an enormous growth in the volume of structured and semi-structured data sets available on the Web. An important prerequisite for using and combining such data sets is the detection and merge of information that describes the same real-world entities, a task known as Entity Resolution. To make this quadratic task efficient, blocking techniques are typically employed. However, the high dynamics, loose schema binding, and heterogeneity of (semi-)structured data, impose new challenges to entity resolution. Existing blocking approaches become inapplicable because they rely on the homogeneity of the considered data and a-priory known schemata. In this paper, we introduce a novel approach for entity resolution, scaling it up for large, noisy, and heterogeneous information spaces. It combines an attribute-agnostic mechanism for building blocks with intelligent block processing techniques that boost blocks with high expected utility, propagate knowledg e about identified matches, and preempt the resolution process when it gets too expensive. Our extensive evaluation on real-world, large, heterogeneous data sets verifies that the suggested approach is both effective and efficient. Copyright 2011 ACM.

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The disappearing computer. Interaction design, system infrastructures and application for smart environments
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Digitale Wasserzeichen in eHealth-Anwendungen als Schutzmechanismus für Multimedia-Dateien

2007 , Steinebach, M. , Croce-Ferri, L. , Pharow, P.

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Facilitating asynchronous discussions in learning communities: the impact of moderation strategies

2007 , Kienle, A. , Ritterskamp, C.

A facilitator or moderator is often responsible for supporting processes and their progress in learning communities. In this article we present an approach for supporting moderators of asynchronous processes in learning communities. This approach follows the socio-technical perspective: it includes a theory-based development of moderator tasks and the technical features designed to support these tasks. Starting with relevant work in this area, we describe our approach to moderator support in the collaborative learning environment KOLUMBUS 2. In a qualitative study, a professional moderator facilitated the discussion processes of a group of 12 students based on KOLUMBUS 2. The moderator used different methods and varying levels of participation intervention. The study showed that different intervention strategies led to different levels of student participation and different successes in finding common results at the end of the discussions. Suggestions for the design of technical features are also made.

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Context-oriented communication and the design of computer-supported discursive learning

2008 , Herrmann, T. , Kienle, A.

Computer-supported discursive learning (CSDL) systems for the support of asynchronous discursive learning need to fulfil specific socio-technical conditions. To understand these conditions, we employed design experiments combining aspects of communication theory, empirical findings, and continuous improvement of the investigated prototypes. Our theoretical perspective starts with a context-oriented model of communication which is-as a result of the experiments-extended by including the role of a third-party such as a facilitator. The theory-driven initial design requirements lead to the CSCL-prototype, KOLUMBUS, emphasizing the role of annotations. In KOLUMBUS, annotations can be immediately embedded in their context of learning material. Practical experience with the prototype in five cases reveals possibilities for implementing improvements and observing their impact. On this basis, we provide guidelines for the design of CSDL systems that focus on the support of asyn chronous discursive learning.

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Cross system personalization and collaborative filtering by learning manifold alignments

2007 , Mehta, B. , Hofmann, T.

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Interdisciplinarity in the CSCL community - An empirical study

2007 , Wessner, M. , Kienle, A.

In previous work the CSCL community was analysed with respect to its scope, development, continuity and connectivity (Hoadley 2005, Kienle & Wessner 2005, Kienle & Wessner 2006). Main insights included a relatively low but stable continuity of individuals in the community, increasing international participation and increasing connectivity across different countries. Concerning the disciplines involved in CSCL and the disciplinary backgrounds of CSCL community members it was found that a variety of disciplines are represented in the community. A detailed analysis of the way these disciplines contribute to the progress of CSCL, the way members with different disciplinary backgrounds collaborate is still missing. In this paper we report an analysis of the CSCL community with respect to the disciplinary background of its members and the interrelation of various disciplines in CSCL. The analysis is based on a survey among members of the CSCL community actively involved in th e CSCL 2007 conference (reviewers and authors of accepted contributions). The paper reports and discusses main results of this analysis with respect to disciplinary background of CSCL community members as well as links between the disciplines. In addition it provides insights into motives for interdisciplinary collaboration, beneficial and hindering factors. The results should help to sharpen our view of the CSCL community, contribute to a shared understanding about what CSCL (currently) is (and what is it not) and point out perspectives for future development of the CSCL community.

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Informations- und Wissensmanagement

2007 , Brocks, H. , Hofmann, T. , Kamps, T.

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Intelligent privacy support for large public displays

2007 , Röcker, C. , Hinske, S. , Magerkurth, C.

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Exploiting context information for identification of relevant experts in collaborative workplace-embedded e-learning environments

2007 , Lokaiczyk, R. , Godehardt, E. , Faatz, A. , Goertz, M. , Kienle, A. , Wessner, M. , Ulbrich, A.

This work introduces an approach to discover collaboration partners and adequate advising experts in a workplace-embedded collaborative e-learning environment. Based on existing papers dealing with work task and user context modelling, we propose the following steps towards a successful collaboration initiation. In the beginning, the user's current process task needs to be identified (1). Taking into account the knowledge about the current process, availability of experts as well as organizational and social distance, relevant experts regarding the actual work task of the learner are pre-selected by the environment (2). Depending on the pre-selection and users' preferences, the potential collaboration partners are displayed in an expert list (3). That way, the learner is able to initiate beneficial collaborations, whose transcripts are used to enhance the existing knowledge base of learning documents (4).

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