Abstract
Nuclear process control is a complex domain requiring human factors research to ensure the safe, reliable, and efficient operation of nuclear power plants. The aging fleet of U.S. nuclear power plants are undergoing control room modernization. This control room modernization effort focuses on upgrading the human system interfaces with advanced digital interfaces. To aid this effort, the Rancor Microworld was developed as a platform to examine human factors and related psychological constructs in the complex nuclear process control domain. Rancor was designed for use with novice student populations to augment full-scope simulation studies using expert operator participants. Students and operators were evaluated while they completed the Rancor Microworld process control task. Several aspects of human performance were examined, including primary process control task performance, situation awareness, and patterns of attention. Situation awareness, a key element of complex process control, was assessed with SAGAT-like and SACRI-like freeze probes. Patterns of attention were assessed using a traditional eye tracking fixation measure. Additionally, a new simple attention-acknowledgement measure was proposed, developed, and evaluated to provide researchers with another method of assessing attention within the complex process control domain. Results from this work suggest students and operators demonstrate similar performance with a noticeable decrement for operators, likely due to negative expertise transfer, during the first trial. Operators demonstrated better situation awareness than students, which suggests there is at least one key difference between the novice student and expert operator populations. The eye tracking fixation-based measure and the attention-acknowledgement measure of attention both assessed similar patterns of attention during the Rancor Microworld task. Additionally, both measures were sensitive to different patterns of attention for the various process control subtasks, which indicates the attention-acknowledgement measure is an effective method for assessing patterns of attention in a complex nuclear process control domain.