• Journal of the Ergonomics Society of Korea
• /
• v.32 no.1
• /
• pp.87-96
• /
• 2013

Objective: The aim of this study is to describe several issues which should be considered in the human reliability analysis of soft control operations in nuclear power plants. Background: The operational environment of advanced main control rooms is totally different from that of conventional control rooms. The soft control is one of the major distinguishable features of the advanced main control rooms. The soft control operations should be analyzed to estimate the effects on human reliability. Method: The literatures, about task analysis, simulation data analysis, and a human reliability analysis method for the soft control, were reviewed. From the review, important issues for the human reliability analysis of the soft control were raised. Results: The results of task and simulation data analysis showed that the soft control characteristics could have large effect on human reliability and they should be considered in the human reliability analysis of the soft control operations. Conclusion: The soft control may affect human error and performance of operators. The issues described in this paper should be considered in the human reliability method for the advanced main control rooms. Application: The results of the soft control operation analysis might help to design more efficient interface and education/training program for preventing human errors. The described issues might help to develop a human reliability analysis method for soft control operations.

• Journal of the Ergonomics Society of Korea
• /
• v.30 no.1
• /
• pp.55-64
• /
• 2011

Objective: The aim of this paper is to introduce the activities and research trends of human reliability analysis including brief summary about contents and methods of the analysis. Background: Various approaches and methods have been suggested and used to assess human reliability in field of risk assessment of nuclear power plants. However, it has noticed that there is high uncertainty in human reliability analysis which results in a major bottleneck for risk-informed activities of nuclear power plants. Method: First and second generation methods of human reliability analysis are reviewed and a few representative methods are discussed from the risk assessment perspective. The strength and weakness of each method is also examined from the viewpoint of reliability analyst as a user. In addition, new research trends in this field are briefly summarized. Results: Human reliability analysis has become an important tool to support not only risk assessment but also system design of a centralized complex system. Conclusion: Human reliability analysis should be improved by active cooperation with researchers in field of human factors. Application: The trends of human reliability analysis explained in this paper will help researchers to find interest topics to which they could contribute.

• Proceedings of the ESK Conference
• /
• 1996.04a
• /
• pp.113-127
• /
• 1996

In Human Reliability Analysis(HRA), the uncertainties involved in many factors that affect human reliability have to be represented as the quantitative forms. Conventional probability- based human reliability theory is used to evaluate the effect of those uncertainties but it is pointed out that the actual human reliability should be different from that of conventional one. Conventional HRA makes use of error rates, however, it is difficult to collect data enough to estimate these error rates, and the estimates of error rates are dependent only on engineering judgement. In this paper, the error possibility that is proposed by Onisawa is used to represent human reliability, and the error possibility is obtained by use of fuzzy reasoning that plays an important role to clarify the relation between human reliability and human error. Also, assuming these factors are connected to the top event through Fault Tree structure, the influence and correlation of these factors are measured by fuzzy operation. When a fuzzy operation is applied to Fault Tree Analysis, it is possible to simplify the operation applying the logic disjuction and logic conjuction to structure function, and the structure of human reliability can be represented as membership function of the top event. Also, on the basis of the the membership function, the characteristics of human reliability can be evaluated by use of the concept of pattern recognition.

• Journal of the Korea Management Engineers Society
• /
• v.23 no.4
• /
• pp.159-164
• /
• 2018

Human-machine serial systems must be normal in both systems. Though the failure of machine is irreducible by itself, the human errors are of recurring type. When the human performance is described quantitatively, non-homogeneous Poisson Process model of human errors can be developed. And the model parameters can be estimated by maximum likelihood estimation and numerical analysis method. System reliability is obtained by multiplying machine reliability by human reliability.

• Nuclear Engineering and Technology
• /
• v.55 no.3
• /
• pp.801-813
• /
• 2023

The events at Three Mile Island in the United States brought about fundamental changes in the ways that simulation would be used in nuclear operations. The need for research simulators was identified to scientifically study human-centered risk and make recommendations for process control system designs. This paper documents the human factors research conducted at the Human Systems and Simulation Laboratory (HSSL) since its inception in 2010 at Idaho National Laboratory. The facility's primary purposes are to provide support to utilities for system upgrades and to validate modernized control room concepts. In the last decade, however, as nuclear industry needs have evolved, so too have the purposes of the HSSL. Thus, beyond control room modernization, human factors researchers have evaluated the security of nuclear infrastructure from cyber adversaries and evaluated human-in-the-loop simulations for joint operations with an integrated hydrogen generation plant. Lastly, our review presents research using human reliability analysis techniques with data collected from HSSL-based studies and concludes with potential future directions for the HSSL, including severe accident management and advanced control room technologies.

• Journal of the Ergonomics Society of Korea
• /
• v.16 no.2
• /
• pp.1-14
• /
• 1997

In conventional probability-based human reliability analysis, the basic human error rates are modified by experts to consider the influences of many factors that affect human reliability. However, these influences are not easily represented quantitatively, because the relation between human reliability and each of these factors in not clear. In this paper, the relation is expressed quantitatively. Furthermore, human reliability is represented by error possibilities proposed by Onisawa, which is a fuzzy set on the interval [0,1]. Fuzzy reasoning is used in this method in order to obtain error possibilities. And, it is supposed that many basic events affected by the above factors are connected to the top event through Fault Tree structure, and an estimate of the top event expressed by a member- ship function is obtained by using the fuzzy measure and fuzzy integral. Finally, a numerical example of human reliability analysis obtained by this method is given.

• Journal of Korean Society for Quality Management
• /
• v.20 no.2
• /
• pp.94-108
• /
• 1992

This study involves an experiment for the cognitive experiment design and the human reliability in software engineering. Its overall objectives are to analyze common-cause human domain error and reliability in human-software interaction. A laboratory study was performed to analyze software engineers' task behavior in software production and to identify software design factors contributing to the effects in common cause failure redundancy. Common-cause model and its function were developed, then the main experiment using programming experts was conducted in order to define a new cognitive paradigm, in the aspects of identification, pattern recognition, and behavior domain for human reliability and quality control in software development. The results and analytical procedures developed in this research can be applied to reliability improvement and cost reduction in software development for many applications. Results are also expected to provide guidelines for software engineering quality control and for more effective design of human-software interface system.

• Nuclear Engineering and Technology
• /
• v.53 no.2
• /
• pp.368-375
• /
• 2021

The performance time of human operators has been recognized as a key aspect of human reliability in socio-complex systems, including nuclear industries. Because of the importance of the time factor, most existing human reliability assessment methods provide ways to quantify human error probabilities (HEPs) that are associated with the performance time. To quantify such kinds of HEPs, it is crucial to rationally predict the length of time required and time available and compare them. However, there have not been detailed guidelines that identify the critical cue presentation time or initial time of human performance, which is important to calculate the time information. In this paper, we introduce a time-related HEP calculation technique with a decision algorithm that determines the critical cue and its timing. The calculation process is presented with the application examples. It is expected that the proposed algorithm will reduce the variability in the time-related reliability assessment and strengthen the scientific evidence of the assessment process. The detailed description is provided in the technical report KAERI/TR-7607/2019.

• Fashion & Textile Research Journal
• /
• v.24 no.2
• /
• pp.229-240
• /
• 2022

This study explores the effect of anthropomorphism on fashion chatbot reliability, mediated by perceived intelligence and cognitive evaluation. The moderating effects of individuals' need for human interaction between chatbot anthropomorphism and perceived intelligence, cognitive evaluation, and chatbot reliability are also explored. Participants, who were recruited through the online research firm, responded to questions after watching a video clip showing a conversation with a fashion chatbot on a mobile screen. The data were collected through Mturk, a crowdsourcing platform with an online research panel. All responses (N = 212) were analyzed using SPSS 26.0 for the descriptive statistics, frequency analysis, reliability analysis, exploratory factor analysis, and PROCESS procedure. The results demonstrate that chatbot anthropomorphism increases chatbot reliability, and this is mediated by chatbot intelligence. Although chatbot anthropomorphism increases cognitive evaluation, the effect of cognitive evaluation on chatbot reliability is not significant; thereby, the effect of chatbot anthropomorphism on chatbot reliability is not mediated by the cognitive evaluation. The direct effect of anthropomorphism on chatbot reliability is also moderated by individuals' need for human interaction. For participants with a high need for human interaction, chatbot anthropomorphism increases chatbot reliability; however, anthropomorphism does not significantly affect chatbot reliability for participants with a low need for human interaction. The study's findings contribute to expanding the literature on consumers' new technology acceptance by testing the antecedents affecting service reliability.

• Nuclear Engineering and Technology
• /
• v.52 no.9
• /
• pp.1983-1989
• /
• 2020

The human reliability analysis is a method by which, in general terms, the human impact to the safety and risk of a nuclear power plant operation can be modelled, quantified and analysed. It is an indispensable element of the PSA process within the nuclear industry nowadays. The paper herein presents a sensitivity study of the human reliability analysis performed on a real nuclear power plant-specific probabilistic safety assessment model. The analysis is performed on a pre-selected set of post-initiator operator actions. The purpose of the study is to investigate the impact of these operator actions on the plant risk by altering their corresponding human error probabilities in a wide spectrum. The results direct the fact that the future effort should be focused on maintaining the current human reliability level, i.e. not letting it worsen, rather than improving it.