DOCTORAL SEMINAR: Mashups by Orchestration and Widget-based Personal Environments: Key Challenges, Solution Strategies, and an Application

Location: Celestijnenlaan 200A, Room 200A.05.001, 3001 Leuven-Heverlee

by Ahmet Soylu, PhD Student in Computer Science

Mashups have been studied extensively in the literature; nevertheless, the large body of work in this area focuses on service/data level integration and leaves UI level integration, hence UI mashups, almost unexplored. The latter generates digital environments in which participating sources exist as individual entities; member applications and data sources share the same graphical space particularly in the form of widgets. However, the true integration can only be realized through enabling widgets to be responsive to the events happening in each other. We call such an integration widget orchestration and the resulting application mashup by orchestration. This article aims to explore and address challenges regarding the realization of widget-based UI mashups and UI level integration, prominently in terms of widget orchestration, and to assess their suitability for creation of web-based personal environments. We provide a holistic view on mashups and a theoretical grounding for widget-based personal environments. We identified the following challenges: widget interoperability, end-user data mobility as a basis for manual widget orchestration, user behavior mining - for extracting behavioral patterns - as a basis for automated widget orchestration, and infrastructure. We introduce functional widget interfaces for application interoperability, exploit semantic web technologies for data interoperability, and realize end-user data mobility on top of this interoperability framework. We employ semantically enhanced workflow/process mining techniques, along with Petri nets as a formal ground, for user behavior mining. We outline a reference platform and architecture, compliant with our strategies, and extend W3C widget specification respectively - prominently with a communication channel - to foster standardization. We evaluate our solution approaches regarding interoperability and infrastructure through a qualitative comparison with respect to existing literature, and we provide a computational evaluation of our behavior mining approach. We have implemented a prototype for a widget-based personal learning environment for foreign language learning to demonstrate the feasibility of our solution strategies. The prototype is also used as a basis for the end-user assessment of widget-based personal environments and widget orchestration. Evaluation results suggest that our interoperability framework, platform, and architecture have certain advantages over the existing approaches and proposed behavior mining techniques are adequate for the extraction of behavioral patterns. User assessments show that widget-based UI mashups with orchestration (i.e., mashups by orchestration) are promising for the creation of personal environments as well as for an enhanced user experience. This article provides an extensive exploration of mashups by orchestration and their role in the creation of personal environments. Key challenges are described, along with novel solution strategies to meet them.