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Astract: Model transformations play a key role in the vision of Model- Driven Engineering (MDE) whereby the overcoming of structural heterogeneities, being a result of applying different meta-modeling constructs for the same semantic concept, is a challenging, recurring problem, urgently demanding for reuse of transformations. In this respect, an approach is required which (i) abstracts from the concrete execution language allowing to focus on the resolution of structural heterogeneities, (ii) keeps the impedance mismatch between specification and execution low enabling seamless debuggability, and (iii) provides formal underpinnings enabling model checking. Therefore, we propose to specify model transformations by applying a set of abstract mapping operators (MOPs), each resolving a certain kind of structural heterogeneity. For specifying the operational semantics of the MOPs, we propose to use Transformation Nets (TNs), a DSL on top of Colored Petri Nets (CPNs), since it allows (i) to keep the impedance mismatch between specification and execution low and (ii) to analyze model transformations by evaluating behavioral properties of CPNs.

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Astract: Social networks have seen enormous growth over the past few years, providing also a powerful new channel for distributing personalized services. Personalization, however, is exacerbated because social content is scattered across different social networks serving specific human needs and social networkers are particularly reluctant to share social content with service providers, if not under their full control. This paper sketches TheHiddenU, a social nexus exploiting semantic techniques for integrating, profiling and privatising social content, thereby providing the technical prerequisites for personalized brokerage, a new, sustainable business model in the Social Web.

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Astract: Abstract. Metamodel evolution and model co-evolution are considered to be essential ingredients for the successful adoption of model-driven engineering in practice. In this respect, on the one hand, dedicated co-evolution languages have been proposed for migrating models conforming to an initial metamodel to models conforming to a revised metamodel with the drawback of requiring to learn a new language. On the other hand, the employment of dedicated model-to-model transformation languages has been proposed demanding for the speci cation of rules for copying unchanged elements. In this paper, we propose to tackle the co-evolution problem from a di erent viewpoint. Instead of describing the co-evolution of models as a transformation between two metamodels, we employ existing inplace transformation languages. For this, the prerequisite is to represent both language versions within one metamodel which is automatically computed by merging the initial and the revised metamodel. This ensures that the initial as well as the revised model conform to the merged metamodel, enabling the employment of inplace transformations for initializing new metamodel elements. Finally, a check-out transformation is used for eliminating model elements which are no longer covered by the revised metamodel.We demonstrate this idea by using ATL for merging the metamodels and realizing the check-out transformation. Furthermore, we discuss the ATL re nement mode for co-evolving the models.

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Astract: Software engineering deals with the development of complex software systems which is an inherently team-based task. Therefore, version control support is needed to coordinate the teamwork and to manage parallel modifications. If conflicting modifications occur, in standard approaches the developer who detected the conflict is responsible for the conflict resolution alone and has to resolve the conflict immediately. Especially in early project phases, when software models are typically employed for brainstorming, analysis, and design purposes, such an approach bears the danger of losing important viewpoints of different stakeholders and domain engineers, resulting in a lower quality of the overall system specification. In this paper, we propose conflict-tolerant model versioning to overcome this problem. Conflicts are marked during the merge phase and are tolerated temporarily in order to resolve them later in a collaborative setting. We illustrate the proposed approach for the standardized modeling language UML and discuss how it can be integrated in current modeling tools and version control systems.

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Astract: The urgent demand for optimistic version control support for software models induced active research within the modeling community. Recently, several approaches have been proposed addressing the task of detecting conflicts when merging two concurrently changed versions of a model. In this context, the holistic representation and supportive visualization of detected merge conflicts pose a challenge. In this paper, we present a modeling language independent conflict model comprising all necessary information to profoundly represent merge conflicts. From this conflict model, we leverage the dynamic extension power of UML profi les by introducing a dedicated conflict pro file to visually assist modelers in resolving merge conflicts of UML models. As a result, modelers may resolve conflicts in the concrete graphical syntax conducting their familiar UML editors without tool extensions.