We have automated a Seeman-Bohlin Guinier x-ray diffractometer by interfacing it to a minimally configured PDP 11/23 computer. The programs that run on the microcomputer to control the operation of the diffractometer are stored on a mainframe host running the UNIX+ operating system. A software interface allows a particular data acquisition program to be downloaded from the UNIX host and executed on the satellite processor. This same interface allows the collected data to be periodically off-loaded to the host for processing and storage.
Models of users' procedural knowledge were derived from the records of command usage obtained from nine experienced users of the Unix operating system. Pairwise transitions between user command entries were analyzed for the purpose of identifying salient command patterns associated with task-based user behaviors. Structural models of command usage patterns were obtained from Pathfinder network scaling of Unix command events. The network representation of command patterns was evaluated as a method for abstracting users' procedural knowledge. These network scaling solutions revealed patterns that were common both within and across users' command usage.
Obfuscating Live Computer Forensic Investigative Process on a Windows 7 Operating System: A Criminal's Perspective
