• Nuclear Engineering and Technology
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• v.36 no.1
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• pp.64-72
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• 2004

The purpose of this study is to develop a system dynamics model for the assessment of the organizational and human factors in a nuclear power plant which contribute to nuclear safety. Previous studies can be classified into two major approaches. One is the engineering approach using tools such as ergonomics and Probability Safety Assessment (PSA). The other is the socio-psychology approach. Both have contributed to find organizational and human factors and to present guidelines to lessen human error in plants. However, since these approaches assume that the relationship among factors is independent they do not explain the interactions among the factors or variables in Nuclear Power Plants. To overcome these restrictions, a system dynamics model, which can show cause and effect relationships among factors and quantify the organizational and human factors, has been developed. Handling variables such as the degree of leadership, the number of employees, and workload in each department, users can simulate various situations in nuclear power plant organization. Through simulation, users can get insights to improve safety in plants and to find managerial tools in both organizational and human factors.

• Journal of Environmental Impact Assessment
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• v.20 no.5
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• pp.729-745
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• 2011

The purpose of this paper is to estimate the external diseconomies of an unwelcomed facility on the nearby houses. The facility and the area studied are Dangin-Ri power plant in Mapo-Gu, Seoul and the residential district surrounding it respectively. The nearby housing prices have been changed according to the time and circumstances of the public announcements about the reconstruction or removal plans of the plant. These price changes are regarded as the capitalized values of the external diseconomies due to the plant. This study is based on the hedonic price theory in order to estimate the diseconomies in monetary value. The tools for the estimation are four models of multiple regression with the transaction price as the dependant variable and various housing characteristics including the external effects of the plant as the independent variables. The sample analyzed is 833 house transactions for the past 5 years in the research area. The facts found are as follows; First, the most suitable functional form for the estimation is confirmed to be the linear model. Second, there are significant differences in influence on the housing values among the independent variables, that is, locational characteristics, physical features, and environmental changes with time. Third, the external diseconomy is estimated as \80,137,807 in case that the plant would be reconstructed in the underground of the present site, whereon a substitutional public park would be constructed and as \59,142,248 in case that the plant would move away.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.4
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• pp.830-837
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• 2011

A turbine control system which has been operated for years in a nuclear power plant was retrofitted with a newly developed digital control system. After completion of the retrofit, turbine valve tests were performed to ensure the integrity of each valve's control function. The sequence of each valve test is composed of a closing process and a reopening process. To minimize megawatt variation which normally occurs during the test sequence, we employed a kind of compensator algorithm in the new digital control system which also have been used in the old system. There were difficulties finding optimal parameter settings for our new compensator algorithm because the power plant didn't allow us to perform necessary tuning procedures while the turbine is on load operation. Therefore an alternative measure for the compensator tuning which is independent of the turbine actual operation had to be implemented. So, a process model for the test was required to overcome this situation. We analyzed the operation data of the test and implemented the process model by use of input and output variable relations. Also we verified the process model by use of another condition's operating data. The result shows that the output of model is similar to the actual operation data.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.3
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• pp.154-158
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• 2011

This research was carried out to compare the standard of estimated unit power and material in landscape architecture construction between Korea and Japan. It has also been done to offer a practical and reasonable information to Korea landscape architecture industry. The research results are as follows. First, both Korea and Japan's standard of estimated unit power and material in landscape architecture construction are part of civil construction. Second, Korea's detailed type of construction is centered on plant's type and size while Japan's centered on architectural construction. Third, Korea's standard of estimated unit power and material are composed of workforce construction, mechanical construction and addition of soil. On the other hand, Japan's estimated unit power and material are composed of workforce construction, time of transportation, date of transportation. Fourth, the planting specification of Korea seems to be more in detail than that of Japan, Japan's showing a wider implication. Fifth, when comparing the information regarding standard of estimated unit power and material between Japan and Korea, transportation, independent stalking for plant, soil for landscape architecture is difference between the two countries. On the base of this research results, Korea's standard of estimated unit power and material in planning construction should be more elastic in its implication and independent standard of estimated unit power and material in landscape architecture construction. Also, examination of transportation, independent skating for plant and soil for landscape architecture should be done in order for better improvements.

• Journal of Korean Society for Quality Management
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• v.46 no.2
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• pp.351-374
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• 2018

Purpose: The collective civil complaint problem is considered as important obstructive factor of the nuclear power plant construction project's success and quality. Therefore, this study demonstrate the factors which can affect the settling collective civil complaints, and also suggest the improvement of the resolution. Methods: This study collected the data of Kori Nuclear Power Division staff, local residents and Hanul Nuclear Power Division staff, local residents, and use them for analysis. Results: The results are twofold in the study: First, the 'Situation Recognition' and 'Mutual Cooperation' which are independent variables for solving collective civil complaints have proved to give positive influence on both the nuclear staff and the local residents about the complaint resolution outcome of the dependent variable. Second, the moderation variable 'Expected Benefit' on the influential relationship between the collective civil complaint resolution factor and the civil complaints resolution outcome proved to have a moderating effect only on the nuclear staff. On the other hand, moderation variables 'Time of SOC Business Implementation' and 'Time of Compensation' proved to have a moderating effect only for the local residents. Conclusion: According to the results, the staff have a positive opinion on the benefits of the nuclear power plant construction, while residents feel strongly that they do not get any benefit from the construction despite of tremendous investment and expected benefit in local area. As this results, policy implementation which is superable different understanding is required.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.4
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• pp.321-329
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• 1998

Structural integrity of nuclear components is important for a safe operation of nuclear power plants. Therefore, nuclear power plants require to perform reliable, periodic inservice inspections. Korea Electric Power Company(KEPCO) operates the entire Korean nuclear power plants. Since nuclear power plant safety and the associated inservice inspection(ISI) are under the plant owner's responsibility, Korea Electric Power Research Institute(KEPRI), the R&D division of KEPCO, has established the ISI NDE Total Support system(TSS) for an efficient performance of ISI tasks, and initiated both key ISI NDE technology development program and traing & qualification system development program for an independent ISI operation. This paper describes details of these programs.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.905-913
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• 2017

Advanced reactor designs often feature longer operating cycles between refueling and new concepts of operation beyond traditional baseload electricity production. Owing to this increased complexity, traditional proportional-integral control may not be sufficient across all potential operating regimes. The prototypical advanced reactor (PAR) design features two independent reactor modules, each connected to a single dedicated steam generator that feeds a common balance of plant for electricity generation and process heat applications. In the current research, the PAR is expected to operate in a load-following manner to produce electricity to meet grid demand over a 24-hour period. Over the operational lifetime of the PAR system, primary and intermediate sodium pumps are expected to degrade in performance. The independent operation of the two reactor modules in the PAR may allow the system to continue operating under degraded pump performance by shifting the power production between reactor modules in order to meet overall load demands. This paper proposes a Takagi-Sugeno (T-S) fuzzy logic-based power distribution system. Two T-S fuzzy power distribution controllers have been designed and tested. Simulation shows that the devised T-S fuzzy controllers provide improved performance over traditional controls during daily load-following operation under different levels of pump degradation.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.2059-2063
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• 2004

Most power plants have operated many independent computerize systems for maintenance. Independence of systems have caused complexity of business process and inconvenience of computer system management. Because the equipment and material master data is not standardize and structurize, it is difficult to manage equipment maintenance history and material delivery. Especially equipment classification criterion is important for standardization of every maintenance information. It is necessary to integrate function of independent systems for business process simplification and rapid work flow. this paper provides equipment classification criterion design and system integration method with the case of live system development.

• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1163-1170
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• 2014

Due to global environmental regulations and policies with rapid advancement of renewable energy technologies, the development type of renewable energy sources (RES) in power systems is expanding from small-scale distributed generation to large-scale grid-connected systems. In the near future, it is expected that RES achieves grid parity which means the equilibrium point where the power cost of RES is equal to the power costs of conventional generators. However, although RES would achieve the grid parity, the cost related with development of large-scale RES is still a big burden. Furthermore, it is hard to determine a suitable capacity of RES because of their output characteristics affected by locations and weather effects. Therefore, to determine an optimal capacity for RES becomes an important decision-making problem. This study proposes a method for determining an optimal installed capacity of RES from the business viewpoint of an independent power plant (IPP). In order to verify the proposed method, we have performed case studies on real power system in Incheon and Shiheung areas, South Korea.

• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.559-568
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• 2017

Objective: The aim of this study is to investigate the effective managerial factors influencing dose reduction of the nozzle dam installation and removal tasks ranking within top 3 in viewpoint of average collective dose of nuclear power plant maintenance job. Background: International Commission on Radiation Protection (ICRP) recommended to reduce unnecessary dose and to minimize the necessary dose on the participants of maintenance job in radiation fields. Method: Seven sessions of nozzle dam installation and removal task logs yielded a multiple regression model with collective dose as a dependent variable and work time, number of participants, space doses before and after shield as independent variables. From the sessions in which a significant reduction in collective dose occurred, the effective managerial factors were elicited. Results: Work time was the most important factor contributing to collective dose reduction of nozzle dam installation and removal task. Introduction of new technology in nozzle dam design or maintenance job is the most important factor for work time reduction. Conclusion: With extended task logs and big data processing technique, the more accurate prediction model illustrating the relationship between collective dose reduction and effective managerial factors would be developed. Application: The effective managerial factors will be useful to reduce collective dose of decommissioning tasks as well as regular preventive maintenance tasks for a nuclear power plant.