Visualizing the characteristics of a work process being observed from the main control room of nuclear power plants - identifying underlying requirements

One of the disseminated approaches is to identify and manage vulnerable tasks (i.e., error-prone tasks) by applying many kinds of human reliability assessment (HRA) techniques. That is, if HRA practitioners are able to identify plausible error forcing factors (e.g., performance shaping factors; PSFs) under a given task context, effective countermeasures that are helpful for reducing the possibility of human error can be drawn by deducing how to eliminate the associated PSFs. In order to reduce the variability of HRA results, the development of an objective criterion for determining the level of each PSF could be the most plausible countermeasure. In order to address this issue, this paper applied a process mining technique to the analysis of communication logs gathered from main control room (MCR) crews in NPPs, which could be useful for visualizing their characteristics in terms of the Work process. In this study, before providing additional information that is helpful for HRA practitioners in determining the quality of the Work process, three kinds of underlying requirements are identified. They are: (1) an ability to describe the flow of a work, (2) an ability to incorporate time and spatial information into the flow of a work, and (3) an ability to identify the flow of symptoms and/or knowledge being employed by an MCR crew. In order to satisfy these requirements, a couple of techniques can be used. This might allow partial pooling of log information according to how the information can be clustered.' In other words, the process mining technique is very useful for discovering the flow of a work being involved in a given situation, it is strongly expected that the analysis of communication logs that allow us to understand what and how they did in order to cope with a situation at hand. If so, it is possible to visualize necessary information that is essential for minimizing the variability of HRA practitioners who have to determine the quality of the Work process