In the field of remote technologies for nuclear power plant (NPP), to reduce hazardous works for human labor during NPP maintenance, an automatic multi-stud tensioning machine using for the cap of the rector pressure vessel is developed [Citation1]. The position of meters for measuring elongations of each studs are controlled by a 2-DOF arm mechanism, and the anti-swing control is proposed to eliminate the swing phenomenon. This development can also contribute to save the overall operation time.
To ensure relatively high precision navigation of underwater remote-operated vehicle (ROV) in the reactor pool of NPP, a new navigation algorithm combining the propellers’ rotating speed detection and hydrodynamics analysis to deduce a position of the ROV and correcting deduced position by using sonar data is proposed [Citation2].
Another group also proposes a new localization method for ROV based on map-matching [Citation3]. This method refers cross-sectional shape date cut from a three-dimensional computer-aided design date as an environmental map and structural shapes measured by a scanning-type ultrasonic sensor as a rage sensor.
For Fukushima Daiich Nuclear Power Station, a remote radiation imaging system comprising a lightweight Compton camera and a multi-copter drone, which is superior to control in narrow space than conventional helicopters, has been developed to remotely and quickly measure radioactive contamination inside the building [Citation4].
In the field of safety design of NPP, reliability of the digital reactor protection system (RPS) has been researched to ensure the safety and economy which can be measured respectively by the probability of failure on demand (PDF) and probability of spurious trip (PST). PDF and PST are the two main modes that should be evaluated for the reliability of digital RPS, these calculation formulas considering the module repair time and common cause failure are developed [Citation5].
In order to operate NPP safely, there is a proposal that a hybrid of principal component analysis (PCA), signed directed graph (SDG) and Elman Neural Network (ENN) for fault detection, fault isolation and severity estimation, respectively [Citation6]. An integrated diagnostic method based on PCA, SDG and ENN is able to detect, identify and diagnose faults of NPP and more faults information will be provided for the operators which served as a good foundation for further decision makings.
In human factor research studies of NPP, most of them focus on operators’ behaviors in emergency situations, and computer simulations or subject experiments with NPP simulators have been often conducted. Two examples are appeared by same research organization that operational procedures generated by using the plant model (MFM; Multilevel Flow Modeling) were proposed [Citation7,Citation8].
Human factor research studies for advanced main control room (AMCR) have been also active for these several years. AMCR offers various operation support systems utilizing computers, large screen displays and individual terminals, while human centered design is the most important concept and many researchers seek the methodology for that. One example is that human-machine interaction design method for digitalized system was proposed using scenario simulator and interaction simulator with knowledge-base and DID risk monitor [Citation9].
References
- Haoyuan L, Meng L, Duan X, et al. Development and anti-swing control of an automated measurement robot system for multi-stud tensioning machine. J Nucl Sci Technol. 2017;54:850–861.
- Dong M, Chou W, Yao G. A new navigation strategy for underwater robot in reactor pool combined propeller speed detection and dynamics analysis with sonar data correction. J Nucl Sci Technol. 2018;55:1–10.
- Kobayashi R, Kono N. Development of localization system using ultrasonic sensor for an underwater robot to survey narrow environment. J Nucl Sci Technol. 2018;55:733–745.
- Sato Y, Ozawa S, Terasaka Y, et al. Remote radiation imaging system using a compact gamma-ray imager mounted on a multicopter drone. J Nucl Sci Technol. 2018;55:90–96.
- Zhanguo M, Yoshikawa H, Yang M. Reliability model of the digital reactor protection system considering the repair time and common cause failure. J Nucl Sci Technol. 2017;54:539–551.
- Yongkuo L, Zhi-Bin W, Ayodeji A, et al. An integrated hybrid intelligence fault diagnosis method for nuclear power plants. J Nucl Sci Technol. 2018;55:254–266.
- Gofuku A, Inoue T, Sugihara T. A technique to generate plausible counter operation procedures for an emergency situation based on a model expressing functions of components. J Nucl Sci Technol. 2017;51:521–525.
- Suryono T, Gofuku A. Techniques to derive additional information of operation actions for computer based operating procedure. J Nucl Sci Technol. 2017;51:521–525.
- Ma Z, Hidekazu Y, Nawaz A, et al. A new human-machine interaction evaluation method by combination of accident simulation and plant did risk monitor. J Nucl Sci Technol. 2017;51:521–525.