Abstract
A well-designed human-computer interface for the visual display unit (VDU) in the control room of a complex environment can enhance operator efficiency and, thus, environmental safety. In fact, a cognitive gap often exists between an interface designer and an interface user. Therefore, the issue of the cognitive gap of interface design needs more improvement and investigation. The main tasks of the operators in the MCR are to constantly monitor the VDU and to ensure the system is stable and functioning normally. While the VDU interface may follow the design guidelines, a cognitive gap may still emerge between designers and users. Hence, the purpose of this research is to evaluate the VDU interface by two experiments. The ecological interface design (EID) framework was utilized in experiment 1 to improve the VDU interface of nuclear power plant (NPP). Experiment 2 is to examine operator performance while using computerized procedures from the perception of the different quantification of information. Experiment 1 presents an application of ecological interface design (EID) into three different cases, demonstrating that EID based framework can support operators in any situations, such as different levels of automation (LOA) and emergency situation in a Nuclear Power Plant (NPP) in Taiwan. A simulated feed-water system was developed to present two different interfaces styles. This study applied the NASA-TLX instrument to evaluate mental workload and also applied the situational awareness rating technique (SART) for assessing situation awareness. With regard to the experiment 2, simulated computer-based procedures (CBPs) were developed to present three information quantity styles. Operation time results were recorded to evaluate operator performance. A secondary task performance was incorporated to measure the redundancy of an operator faced with multiple tasks. NASA-TLX was also applied to evaluate the operators’ mental workload. The results of experiment 1 suggest that EID-based interface has a remarkable advantage in supporting operator performance in terms of response time and accuracy rate under both normal and emergent situation. The results of experiment 2 suggested that medium information quantity of five to eight events has a remarkable advantage in supporting operator performance under both simple and complex task. The results of this study could be a reference and might be applicable to other NPPs in Taiwan, or other complex control systems such as thermal power plant, chemical plants, oil refinery, and air traffic control to improve system reliability as well as life safety in Taiwan.