There have been many attempts to define a straightforward definition for presence, largely without success. Indeed, it is tempting to try and derive a simple measure for the amount of presence a particular system is able to provide and then relate this to user task performance. Unfortunately, this approach is flawed because presence is a multidimensional parameter that is arguably an umbrella t...

This study demonstrates an application of entropy for information theory in the field of survey scale. Based on computer anxiety scale we obtain that the desired information may be achieved with fewer questions. In particular, one question is insufficient and two questions are necessary for a survey subscale.

Cloud computing, one type of distributed systems, is becoming very popular. It has demonstrated easily processing very large data over commodity clusters is possible with correct programming model and infrastructure. One critical issue here lies in the file system (FS) [1]. In this report, I reviewed a number of outstanding distributed file systems (DFS).