Fraunhofer-Institut für Angewandte Informationstechnik FIT

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  • Publication
    Near real-time collaborative modeling for view-based Web information systems engineering
    ( 2018)
    Nicolaescu, P.
    ;
    Rosenstengel, M.
    ;
    Derntl, M.
    ;
    Klamma, R.
    ;
    Jarke, M.
    Conceptual modeling is a creative, social process driven by the views of stakeholders. In modern, agile development - especially for continuously evolving Web applications - contributions from a wide variety of geographically distributed stakeholders, their involvement in negotiation and impact analysis from different perspectives and the rapid prototype generation from specifications gain much importance. Moreover, people have come to expect easy near real-time system support with few restrictions. While conceptual modeling or CSCW environments exist for each of these individual aspects, their interplay has barely been studied. This paper presents a collaborative conceptual modeling approach called SyncMeta that aims to close this gap by supporting view-based modeling in the Web browser in a near real-time shared editing environment1. In addition to domain-specific graphical modeling languages, viewpoints can be collaboratively defined on the meta-modeling layer and instantiated as views within a model editor instance. Besides this formal structure, we also discuss the choice of algorithms for locking-free shared model editing and of highly scalable team size. In addition to this kind of technical evaluation, the paper also presents several medium-scale user studies that have accompanied the iterative SyncMeta development. These studies investigated both the requirements (quality advantages and user acceptance of the view-based approach, near real-time support) and important design options such as centralized vs. peer-to-peer viewpoint resolution. A fully functional SyncMeta software framework which incorporates most of these results, is available in the GitHub open source repository. We expect this line of work to pave the way for methodologies and tools for socially engineered Web information systems.
  • Publication
    Community and trust-aware fake media detection
    ( 2014)
    Rashed, K.
    ;
    Renzel, D.
    ;
    Klamma, R.
    ;
    Jarke, M.
    Nowadays, it becomes increasingly difficult to find reliable multimedia content in the Web 2.0. Open decentralized networks (on the Web) are populated with lots of unauthenticated agents providing fake multimedia. Conventional automatic detection and authentication approaches lack scalability and the ability to capture media semantics by means of forgery. Using them in online scenarios is computationally expensive. Thus, our aim was to develop a trust-aware community approach to facilitate fake media detection. In this paper, we present our approach and highlight four important outcomes. First, a Media Quality Profile (MQP) is proposed for multimedia evaluation and semantic classification with one substantial part on estimating media authenticity based on trust-aware community ratings. Second, we employ the concept of serious gaming in our collaborative fake media detection approach overcoming the cold-start problem and providing sufficient data powering our Media Quality Profile. Third, we identify the notion of confidence, trust, distrust and their dynamics as necessary refinements of existing trust models. Finally, we improve the precision of trust-aware aggregated media authenticity ratings by introducing a trust inference algorithm for yet unknown sources uploading and rating media.
  • Publication
    Learn-as-you-go: new ways of cloud-based micro-learning for the mobile web
    ( 2011)
    Kovachev, D.
    ;
    Cao, Y.
    ;
    Klamma, R.
    ;
    Jarke, M.
  • Publication
    Causal vs. effectual behavior- support for entrepreneurs
    ( 2011)
    Schlüter, J.
    ;
    Schmitz, D.
    ;
    Brettel, M.
    ;
    Jarke, M.
    ;
    Klamma, R.
    "Effectuation" is a new approach to explain the success or failure of entrepreneurs. In contrast to the traditional "causation" approach the entrepreneur is not considered to be driven by a concrete goal and to choose between different alternatives in regard to how well they help to achieve this goal. Instead the entrepreneur evaluates the alternatives, in particular the choice of strategic partners, in regard to their potential for future success. The goals are adapted to the choices and in particular the needs of the strategic partners. Agent-based simulations are intended to help identifying the settings where one approach is more appropriate than the other.
  • Publication
    Der Bazar der Anforderungen
    ( 2011)
    Klamma, R.
    ;
    Jarke, M.
    ;
    Hannemann, A.
    ;
    Renzel, D.
  • Publication
    A clustering approach for collaborative filtering recommendation using social network analysis
    ( 2011)
    Pham, M.C.
    ;
    Cao, Y.
    ;
    Klamma, R.
    ;
    Jarke, M.
    Collaborative Filtering(CF) is a well-known technique in recommender systems. CF exploits relationships between users and recommends items to the active user according to the ratings of his/her neighbors. CF suffers from the data sparsity problem, where users only rate a small set of items. That makes the computation of similarity between users imprecise and consequently reduces the accuracy of CF algorithms. In this article, we propose a clustering approach based on the social information of users to derive the recommendations. We study the application of this approach in two application scenarios: academic venue recommendation based on collaboration information and trust-based recommendation. Using the data from DBLP digital library and Epinion, the evaluation shows that our clustering technique based CF performs better than traditional CF algorithms.
  • Publication
    Development of computer science disciplines
    ( 2011)
    Pham, M.C.
    ;
    Klamma, R.
    ;
    Jarke, M.
    In contrast to many other scientific disciplines, computer science considers conference publications. Conferences have the advantage of providing fast publication of papers and of bringing researchers together to present and discuss the paper with peers. Previous work on knowledge mapping focused on the map of all sciences or a particular domain based on ISI published Journal Citation Report (JCR). Although this data cover most of the important journals, it lacks computer science conference and workshop proceedings, which results in an imprecise and incomplete analysis of the computer science knowledge. This paper presents an analysis on the computer science knowledge network constructed from all types of publications, aiming at providing a complete view of computer science research. Based on the combination of two important digital libraries (DBLP and CiteSeerX), we study the knowledge network created at journal/conference level using citation linkage, to identify the development of sub-disciplines. We investigate the collaborative and citation behavior of journals/conferences by analyzing the properties of their co-authorship and citation subgraphs. The paper draws several important conclusions. First, conferences constitute social structures that shape the computer science knowledge. Second, computer science is becoming more interdisciplinary. Third, experts are the key success factor for sustainability of journals/conferences.
  • Publication
    Well-balanced usability & annotation complexity in interactive video semantization
    ( 2010)
    Renzel, D.
    ;
    Jarke, M.
    ;
    Klamma, R.
    ;
    Lottko, M.
    ;
    Toubekis, G.
    ;
    Jansen, M.
    In the recent years more and more people have begun to edit video files, as technologies are becoming more sophisticated and affordable. Web 2.0 has raised tagging functionality to a growing number of websites such as Flickr and YouTube. However, these services only provide basic video annotation support. In comparison to those well-known services there are many research efforts towards video semantization tools. These tools provide highly precise annotation functionality based on metadata standards such as MPEG-7, but tend to exhibit very complex user interfaces. In this paper we present the design, implementation and evaluation of SeViAnno, an MPEG-7 based interactive semantic video annotation Web platform with the main objective to find a well-balanced trade-off between a simple user interface and video semantization complexity.
  • Publication
    Early experiences with responsive open learning environments
    ( 2010)
    Wolpers, M.
    ;
    Ullrich, C.
    ;
    Renzel, D.
    ;
    Friedrich, M.
    ;
    Klamma, R.