Author Archives: petru

Distributing User Interfaces for Widget-based Web Applications

Ever wondered why not using all your devices as a homogenous environment? Why not distributing parts of a complex application to different devices and keep on using the application and making use of your mobile devices and their specific I/O features? We have developed and demonstrated a framework that can migrate Web widgets to various (mobile) devices without losing the application state in the process and keeping the interactions between the widgets using an inter-widget communication approach. Profiting of this, one can use both mobile and desktop environments together, for a new and rich user experience. The framework was presented as a full paper, together with an invited poster/demo at the International Conference for Web Engineering (ICWE), Aalborg, 2013. Below you can find an abstract, slides and poster.

Web applications have overcome traditional desktop applications especially in collaborative  settings. However, the bulk of Web applications still follow the “single user on a single device” computing model. Therefore, the DireWolf framework was created for rich Web applications with Distributed User Interfaces (DUIs) over a federation of heterogeneous commodity devices supporting modern Web browsers such as laptops, smart phones and tablet computers. The DUIs are based on widget technology coupled with cross-platform inter-widget communication and seamless session mobility. In particular, we built DireWolf on top of the ROLE SDK and its XMPP-based Inter-widget communication. Inter-widget communication connect the widgets and enable real-time collaborative applications as well as runtime migration in our framework. For a single user, DireWolf provides more flexible control over different parts of an application by enabling the simultaneous use of smart phones, tablets and computers. As reference use case of the DireWolf framework we realized a collaborative semantic video annotation application in the domain of cultural heritage documentation.

Prototyping Web-Based and Mobile Apps for Informal Learning: A Semantic Video Annotation Scenario (SeViAnno)

At the Joint Summer School in Technology Enhanced Learning (JTEL) 2013 in Limassol, Cyprus, we held a workshop about semantic video annotation (SeViAnno) as a scaffold for bridging formal and informal learning at the workplace. The workshop was organized as part of our involvement in the Learning Layers EU project. The main objective of the workshop was to actively engage PhD students in design and prototyping activities within the Learning Layers project.

resultsThe workshop audience was composed of PhD students and experts in the TEL domain. The  workshop generated lively discussions in an international, multicultural and dynamic environment about the core research concepts in the Learning Layers project, including learning scaffolds, interaction with digital and physical artifacts and mobile learning. The event turned out to be a good occasion for raising interest around the project and possibly attracting research collaborations for the future.


The students were asked to explore different existing user interfaces for semantic video annotation. They were encouraged to explore the features of the classical Web-based SeViAnno application, of a Widget-based SeViAnno version capable of user interface distribution and of AnViAnno, a vesion running on Android.  After a round of reflection on these different user interface metaphors the participants were asked to design apps and create ideas on how to exploit semantic video annotation for bridging formal and informal learning experiences at the workplace. As a starting point, they were provided with material gathered from application partners in the Learning Layers project by involving the end-user clusters from the construction domain.

Among the ideas discussed as an outcome were annotated 3D animation videos of expected finalized construction work, improving the communication between actors (e.g. master, architect, skilled and apprentice workers, etc.) through semantic video annotation, gamification of the annotation process, real-time feedback through questions, as well as rating and reenactment/circular filming for achieving the best performances in certain scenarios.

IMG_4425Furthermore, it was presumed that semantic annotations are able to capture and characterize work practices––e.g. expected location of various construction artifacts, the sequence of steps necessary in the construction work, and so forth. The annotations could be used to improve the communication between the workers and the masters and ease the capturing and assessment of the work activities. A feedback cycle was also mentioned, where videos can be revised and enriched with new/revised annotations, as a result of the collaboration between workers and masters and the identification of problems and knowledge gaps. Therefore, product reengineering might be necessary or the whole annotation and meaning-making process can be repeated until all involved parties feel confident about the different stages of a construction project.


For maintaining contact with workshop participants and other persons interested in the Learning Layers project and the SeViAnno use case, a design team was established to further promote the ideas generated in the workshop. A dedicated project “JTEL13 Workshop” was also created in the Requirements Bazaar, where everyone can follow the developments in the design team and contribute with new requirements for scaffolding informal learning and peer production by using semantic video annotation.

The workshop slides are available on Slideshare:

More information can also be found at:

For any questions, do not hesitate to contact us!