The objective of this investigation is to determine whether student site location in an instructional videoconference is related to students' motives for communicating with their instructor. The study is based, in part, on the work of Martin et al. who identify five separate student-teacher communication motives. These motives, or dimensions, are termed relational, functional, excuse, participation, and sycophancy, and are measured by a 30-item questionnaire. Several communication-related theories were used to predict differences between on-site and off-site students, Media richness theory was used, foundationally, to explain differences between mediated and face-to-face communication and other theories such as uncertainty reduction theory were used in conjunction with media richness theory to predict specific differences.Two hundred eighty-one completed questionnaires were obtained from Education and Library and Information Science students in 17 separate course-sections employing interactive video at the University of North Texas during the Spring and Summer semesters of the 2001/2002 school year. This study concludes that off-site students in an instructional videoconference are more likely than their on-site peers to report being motivated to communicate with their instructor for participation reasons. If off-site students are more motivated than on-site students to communicate as a means to participate, then it may be important …

The recent advances in mobile computing and distributed multimedia systems allow mobile hosts (clients) to access wireless multimedia Data at anywhere and at anytime. In accessing multimedia information on the distributed multimedia servers from wireless personal communication service systems, a channel assignment problem and synchronization problems should be solved efficiently. Recent demand for mobile telephone service have been growing rapidly while the electro-magnetic spectrum of frequencies allocated for this purpose remain limited. Any solution to the channel assignment problem is subject to this limitation, as well as the interference constraint between adjacent channels in the spectrum. Channel allocation schemes provide a flexible and efficient access to bandwidth in wireless and mobile communication systems. In this dissertation, both an efficient distributed algorithm for dynamic channel allocation based upon mutual exclusion model, and an efficient distributed synchronization algorithm using Quasi-sink for wireless and mobile multimedia systems to ensure and facilitate mobile client access to multimedia objects are proposed. Algorithm's performance with several channel systems using different types of call arrival patterns is determined analytically. A set of simulation experiments to evaluate the performance of our scheme using message complexity and buffer usage at each frame arrival time.