1. TEMPLATE DESIGN © 2008 www.PosterPresentations.com GroupNotes: Encouraging Proactive Student Engagement in Lectures through Collaborative Note-taking on Smartphones Mou Chen School of Computer Science, Engineering and Mathematics, Flinders University Introduction Project Scope System DesignSynchronisation Management User Input Interception - In order to control the cursor in the text area and make it follow the user's intention, the user's keyboard input should be intercepted by the program. Therefore, the text content of the text area is displayed by the program instead of the default text editor, and the cursor will be placed to the new calculated position. Following code segments show how to intercept user's input when user presses a key in the text area: Results Conclusion Further Investigation Contact information In conclusion, backend development was the major part of my participation in the development process of the GroupNotes project. The objective of backend development mainly was to achieve data consistency by contextualization in real-time collaborative Smartphone-based application. By designing system architecture, implementing server/client and synchronisation management, this goal has been substantially achieved, although some further work is required, for example, more comprehensive test cases are needed to testify the performance of application, and also backend part needs to be integrated the with the frontend of the application. The successful design and implementation of the system, combined with the server/client implementation and algorithms of synchronisation management, provide useful information to the GroupNotes Project development team as they continue to refine the application. Thus, significant progress has been made towards enabling this application to be tested in real lectures in the coming future, where several small groups of students using the GroupNotes application in real time, while evaluating the performance of application, hopefully to the benefit of many. Further comprehensive and complex test cases are necessary to evaluate the actual performance of the application. The current application may fail to achieve data consistency while test cases are beyond the scope. Thus, these tests should be repeated in a variety of contexts and application needs to be more intensively implemented to adjust those complex scenarios. Also, the entire work has identified that further effort is required to integrate the existing backend part with the frontend of the application. Additionally, the performance of application can be largely enhanced by introducing specific functionalities such as Swype ®. Application needs to be updated to adjust potential modifications. The goal of the GroupNotes is to allow multiple users to be engaged in a common task or activities involving common interests or goals. Lecture is still the primary teaching and learning form in university and will remain so. However, students disengagement caused by the traditional didactic style of lecture prevents students from taking full benefits of the learning. GroupNotes, as a real-time collaborative notes-taking Smartphone-based application, allows a small session of students to collaboratively interact with each other through taking, reviewing, commentating and questioning notes for lecture contents on slides in real time. GroupNotes provides a student-centred collaborative learning pedagogy into the lecture environment which encourages students to proactively engage themselves by means of student to student interaction on Smartphones. Acknowledgment GroupNotes Project supported by Dr Haifeng Shen, Mark Reilly and School of Computer Science, Engineering and Mathematics of Flinders University. For further information email haifeng.shen@flinders.edu.au Dr Haifeng Shen Flinders University Research Fellow Founder of the GroupNotes Project haifeng.shen@flinders.edu.au Mark Reilly Co-founder of the GroupNotes Project m.reilly@flinders.edu.au Server/Client Implementation GroupNotes, as a technical solution for students to take full benefits of the lectures, allows for personalized multi-user view through flexible layout of multiple windows, personalized content synchronisation through synchronisation protocols and algorithms based on the operational transformation technique. The main objective of the project is to design and implement a real-time collaborative Smartphone-based document editor which achieves data consistency. For example, users can collaborate synchronously or asynchronously, and users should be able to see the changes done by others. Challenging problems include: Divergence, Causality Violation and Intention Violation. Also, the data consistency model needs to be achieved via 3 aspects: Convergence, Causality Preservation and Intention Preservation. Figure 1: A scenario of a real-time collaborative editing session. Figure 5: Code segments of the rewrite Class EditText In a collaborative web-based session, each client maintains an OB(Outgoing Buffer) to store a sequence of local operations that are waiting to be broadcast to other clients and an IB (Incoming Buffer) to store a sequence of remote operations that were waiting to be replayed locally. Communication between server and client relies on HTTP- based protocols to achieve data consistency. The system contains following characteristics : Clients can only communicate with each other through the web server. Clients always initiate the communication connection between the web server in the manner of request/response. Client should send as many requests and to receive as many responses as possible in a roundtrip. Communication between a client and the web server is stateless. A collaborative session involves multiple clients, to achieve data consistency by the SLOT (Symmetric Linear Operational Transformation) and ROR (Responsive Operation Replaying) algorithms, HOB (HTTP-based Operation Broadcast) protocol and session management protocols. In order to achieve data consistency, a set of requirements are proposed: Fast local response, Total work preservation, Unconstrained interaction. In this project, a prototype application is designed and implemented for collaborative Smartphone-based editing. By adopting the contextualization-based OT solution, data consistency is achieved. The system can meet the basic requirements of fast local response, total work preservation and unconstrained interaction. However, problems remain with more complicated text cases, for example, work preservation and fast local response are not completely achieved while more than 2 users are simultaneously interacting. More work needs to be done to improve the performance of current application. The remainder of this poster describes the work to date on backend development of GroupNotes project, including system design, server/client implementation and synchronisation management. Figure 2: A collaborative Web-based session (session p) involving n clients. Figure 3: Server-side data model Web server hosts m collaborative sessions. In particular, session p has n clients. Each client contains its SIB (Server Incoming Buffer) for temporarily storing remote operations which are waiting to be pulled out the client. Figure 4: Client-side data model At client-side, as shown in Figure 4, every time when a user edits local replica, operations are buffered in OB and they are waiting to be broadcasted to other clients via the web server. Operation - A data type that contains all parameters of a key event (Client ID, type, position, text, length) For each client in its relevant session, operation sequences in OB and IB are context-equivalent and therefore need to be transformed with each other for achieving data consistency as well as contextualization. A sequence-oriented transformation control algorithm SLOT is needed to transform two operation sequences in OB and IB against each other. Figure 6: SLOT algorithm