A shannon entropy graph-based model to evaluate the operator mental workload involved in procedure-guided tasks

Recent studies showed that an increasing number of procedures are available in industrial processes, in fields such as maintenance and safety. In many cases, the complexity of a procedure requires a decision-making process to evaluate the correct choice to be adopted in a specific situation. To this concern, the operator is subject to the mental workload to identify the proper strategy to be applied for each case. In the scientific literature, a model that allows evaluating the task complexity of a procedure, through the ‘Shannon Entropy’ applied to graphs, was proposed by J. Park. Similarly, the mental workload of an operator in performing cognitive-oriented tasks was studied by G. Salvendy. Consistently to these topics, the authors propose a new model to estimate the mental workload of an operator during the execution of cognitive-oriented tasks of safety or maintenance procedures. The model has been applied to a numerical simulation; results obtained showed how the complexity of cognitive-oriented tasks of safety or maintenance procedures allows affecting the mental workload. The model can be usefully adopted to design emergency (safety) or maintenance procedures by considering the expected mental workload of operators in performing cognitive-oriented tasks.