Editorial: special issue on ubiquitous electronic commerce systems

Ubiquitous computing is a post-desktop model of human-computer interaction in which information processing has been thoroughly integrated into everyday objects and activities. Emerging ubiquitous electronic commerce systems (UECS) are expected to be available anytime, anywhere, and using different official or personal computing devices. Systems and services such as digital libraries, on-line business transactions, mobile office and mobile TV are widely deployed. Users will be able to access these services anytime, anywhere, while using any computing device in a pervasive way. For example, a user may bring a PDA on a field trip, carry a laptop (with both wireless and wired network cards) on a business trip, use high performance workstations at work, and use desktop PCs at home (with dial-up, cable, or DSL connection). In another example, a user continues to watch the soccer game over home TV, while he watches the game through a mobile device out of home. Some other