  The time people spend in front of computers has been increasing steadily due
to the role computers play in modern society. Individuals who sit in front of
computers for an extended period of time, specifically with improper postures
may incur various health issues. In this work, individuals' behaviors in front
of computers are studied using web cameras. By means of non-rigid face tracking
system, data are analyzed to determine the 3D head pose, blink rate and yawn
frequency of computer users. When combining these visual cues, a system of
intelligent personal assistants for computer users is proposed.
