Now showing 1 - 10 of 67
  • Publication
    Near real-time collaborative modeling for view-based Web information systems engineering
    ( 2018)
    Nicolaescu, P.
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    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
    View-based near real-time collaborative modeling for information systems engineering
    ( 2016)
    Nicolaescu, P.
    ;
    Rosenstengel, M.
    ;
    Derntl, M.
    ;
    Klamma, R.
    ;
    Jarke, M.
    Conceptual modeling is a creative, social process that is driven by the views of involved stakeholders. However, few systems offer view-based conceptual modeling on the Web using lock-free synchronous collaborative editing mechanisms. Based on a (meta-)modeling framework that supports near real-time collaborative modeling and metamodeling in the Web browser, this paper proposes an exploratory approach for collaboratively defining views and viewpoints on conceptual models. Viewpoints are defined on the metamodeling layer and instantiated as views within a model editor instance. The approach was successfully used for various conceptual modeling languages and it is based on user requirements for model-based creation and generation of nextgeneration community applications. An end-user evaluation showed the usefulness, usability and limitations of view-based collaborative modeling.
  • Publication
    A longitudinal study of community-oriented open source software development
    ( 2016)
    Neulinger, K.
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    Hannemann, A.
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    Klamma, R.
    ;
    Jarke, M.
    End-users are often argued to be the source of innovation in Open Source Software (OSS). However, most of the existing empirical studies about OSS projects have been restricted to developer subcommunities only. In this paper, we address the question, if and under which conditions the requirements and ideas from end-users indeed influence the development processes in OSS. We present an approach for automated requirements elicitation process discovery in OSS communities. The empirical basis are three large-scale interdisciplinary OSS projects in bioinformatics, focusing on communication in the mailing lists and source code histories over ten years. Our study results in preliminary guidelines for the organization of community-oriented software development.
  • Publication
    Community and trust-aware fake media detection
    ( 2014)
    Rashed, K.
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    Renzel, D.
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    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
    Early results of experiments with responsive open learning environments
    ( 2011)
    Friedrich, M.
    ;
    Wolpers, M.
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    Shen, R.
    ;
    Ullrich, C.
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    Klamma, R.
    ;
    Renzel, D.
    ;
    Richert, A.
    ;
    Heiden, B. von der
    Responsive open learning environments (ROLEs) are the next generation of personal learning environments (PLEs). While PLEs rely on the simple aggregation of existing content and services mainly using Web 2.0 technologies, ROLEs are transforming lifelong learning by introducing a new infrastructure on a global scale while dealing with existing learning management systems, institutions, and technologies. The requirements engineering process in highly populated test-beds is as important as the technology development. In this paper, we will describe first experiences deploying ROLEs at two higher learning institutions in very different cultural settings. The Shanghai Jiao Tong University in China and at the "Center for Learning and Knowledge Management and Department of Information Management in Mechanical Engineering" (ZLW/IMA) at RWTH Aachen University have exposed ROLEs to theirs students in already established courses. The results demonstrated to readiness of the technology for large-scale trials and the benefits for the students leading to new insights in the design of ROLEs also for more informal learning situations.
  • Publication
    Learn-as-you-go: new ways of cloud-based micro-learning for the mobile web
    ( 2011)
    Kovachev, D.
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    Cao, Y.
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    Klamma, R.
    ;
    Jarke, M.
  • Publication
    Causal vs. effectual behavior- support for entrepreneurs
    ( 2011)
    Schlüter, J.
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    Schmitz, D.
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    Brettel, M.
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    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
    The hero's journey - template-based storytelling for ubiquitous multimedia management
    ( 2011)
    Cao, Y.
    ;
    Klamma, R.
    ;
    Jarke, M.
    Professional communities in research domains including much fieldwork and mobile multimedia acquisition such as the domain of cultural heritage management lack support to create, access, organize and share multimedia within their communities. Digital storytelling is an excellent means to share knowledge represented by ubiquitous multimedia in communities. However, it is not easy for those professional communities to tell and share good digital stories, since they are amateurs in storytelling in many cases. This paper proposes the application of professional story templates to enhance (non-linear) digital storytelling with a template engine allowing users' collaborative design, adaptation and mashing up of story templates. A prototype of the template engine YouTell TE was integrated in a community storytelling platform. A set of case studies demonstrates the usefulness of this approach.
  • Publication
    A clustering approach for collaborative filtering recommendation using social network analysis
    ( 2011)
    Pham, M.C.
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    Cao, Y.
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    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.