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I received PhD from UCLA in 2000. My current research interests include the following, with a focus on collaboration modeling and infrastructure.

Collaboration is an inherent part of our everyday life. People have different and evolutionary ways of collaborating with each other. My research goal is to develop collaborative systems and models to support the cooperative work of users over the Internet, especially end users, in a distributed environment that possibly features a range of (palmtop to wallmounted) displays and devices. Specific ongoing projects explore both collaboration transparent and aware approaches to groupware engineering: The ICT project aims to develop a new generation of application sharing systems that are able to share heterogeneous familiar applications and support unconstrained interaction. The EFG project aims to develop a component-based framework for groupware applications that are adaptable and adaptive during actual use, especially collaboration protocols. Both ICT and EFG are also related to end-user programming and intelligent user interfaces in some way. Besides, as we use editors every day (who does not?) and a wide range of collaborative systems can be modeled as group editors, my group often uses group editors as a testbed application and looks into concurrency control issues, esp. operational transformation algorithms. Current projects can more or less be related back to my early experiences with COCA. Recently I am reorganizing all these projects into one called EXEC, an Evolvable and eXtensible Environment for Collaboration. It aims at providing an infrastructure for supporting everyday collaboration (sort of operating system).

While my projects are things that I can get going with limited resources, my research interests are not necessarily bound by projects. At least, collaborative systems should be interpreted much more broadly than systems/algorithms for synchronous collaboration (which I have been focusing on). Information sharing and human-computer interaction are also part of the story. Also consider the variety of combinations out of {human, computer}: people-people, people-machines-people, people-machines, machine-machine, ... There are indeed a wide spectrum of research problems including systems, algorithms, user interfaces, evaluation methods, and organization issues.


Graduate Students

Projects and Systems

Useful General Advices to Graduate Students

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I teach three classes every year (two semesters). Courses I usually teach include: Collaborative Systems and Models, Computer Supported Cooperative Work, Groupware (undergrad), Database Systems (grad and undergrad), Prolog and AI Programming.

Professional Activities

Selected Publications(For more publications see the projects above)

Consistency Control Algorithms
  1. A performance study of operational transformation algorithms. Du Li and RUi Li. IEEE ICPADS'06 conference. July 2006. Minneapolis, MN.
  2. A new operational transformation framework for realtime group editors. Rui Li and Du Li. IEEE Transactions on Parallel and Distributed Systems (TPDS). 2006. To appear. (early version in GROUP'05)
  3. Commutativity-Based Concurrency Control in Groupware. Rui Li and Du Li. The First IEEE Conference on Collaborative Computing: Networking, Applications and Work Sharing (CollaborateCom'05), Dec. 19-21, 2005, San Jose.
  4. An operational transformation algorithm and performance evaluation. Du Li and Rui Li. Journal of CSCW. 2006. To appear.
  5. Preserving Operation Effects Relation in Group Editors. Du Li and Rui Li. ACM CSCW'04 Conference. Nov. 6-10, 2004. Chicago. (early version in ICDCS'04, journal version in JCSCW 2006 to appear)
  6. A time interval based consistency control algorithm for interactive groupware applications. Rui Li, Du Li, and Chengzheng Sun. IEEE ICPADS'04 conference. July 2004. Newport Beach, CA.
  7. Operation Propagation in Real-Time Group Editors. Du Li, Chengzheng Sun, Limin Zhou, and Richard R. Muntz. IEEE Multimedia. Vol. 7, No. 4, pp. 55-61, Oct.-Dec. 2000 (invited paper)
Collaboration Infrastructures
  1. A framework for building collaboration tools by leveraging industrial components. Du Li, Yi Yang, James Creel, and Blake Dworaczyk. CoopIS'06. Nov. 2006. Montpellier, France.
  2. A lightweight approach to transparent sharing of familiar single-user editors. Du Li and Jiajun Lu. ACM CSCW'06 Conference. Nov. 2006. Banff, Canada.
  3. Separating Data and Control: Support for Adaptable Consistency Protocols in Collaborative Systems. Yi Yang and Du Li. ACM CSCW'04 Conference. Nov. 6-10, 2004. Chicago. (journal version in JCSCW)
  4. Transparent Sharing and Interoperation of Heterogeneous Single-User Applications. Du Li and Rui Li. ACM CSCW'02 Conference. Nov 16-20, 2002. New Orleans, Louisiana, USA.
  5. Ensuring Privacy in Presence Awareness Systems: An Automated Verification Approach.  with Patrice Godefroid, James D. Herbsleb, Lalita J. Jagadeesan at Bell Labs, Lucent Technologies. ACM CSCW'2000 Conference, Dec. 2000, Philadelphia. pp.59-68.
  6. A Collaboration Specification Language. Du Li and Richard R. Muntz, in Proceedings of the 2nd USENIX Conference on Domain Specific Languages (DSL'99), Oct. 99, Austin, Texas.
  7. COCA: Collaborative Objects Coordination Architecture Du Li and Richard R. Muntz, Proceedings of ACM CSCW '98 International Conference on Computer Supported Cooperative Work, Seattle, Nov. 1998, pp. 179-188