Bridging Digital and Physical Worlds Using Tangible Drag-and-Drop Interfaces.-Puppet Playing: An Interactive Character Animation System with Hand Motion Control.-Reconstructing Multiresolution Mesh for Web Visualization Based onPDE Resampling.-On the Development of a Talking Head System Based on the Use of PDE-Based Parametic Surfaces.-Real-Time Spatial and Depth Upsampling for Range Data.-Six Degree-of-Freedom Haptic Rendering for Biomolecular Docking.-Design of a Multiuser Virtual Trade Fair Using a Game Engine.-Applying Biometric Principles to Avatar Recognition.-Range Based Cybernavigation in Natural Known Environments.-Generating Situation Awareness for Time Critical Decision Making.-HumDPM: A Decision Process Model for Modeling Human-Like Behaviors in Time-Critical and Uncertain Situations.-Group-Agreement as a Reliability Measure for Witness Recommendations in Reputation-Based Trust Protocols.-Real-Time EEG-Based Emotion Recognition and Its Applications.

The 12th issue of the Transactions on Computational Science journal, edited by Alexei Sourin and Olga Sourina, is devoted to the topic of cyberworlds. The 13 papers in the volume constitute revised and extended versions of a selection of contributions presented at CW 2010, the 20th International Conference on Cyberworlds, held in Singapore in October 2010. The selected papers span the areas of tangible interfaces, emotion recognition, haptic modeling, decision making under uncertainty, reliability measures, use of biometrics for avatar recognition, cybernavigation, multiuser virtual environments, spatial data sampling, web visualization, and interactive character animation system design.