• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.2
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• pp.103-110
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• 2020

Seismic qualification of instruments and devices mounted on electrical cabinets in a nuclear power plant is performed in this study by means of the in-cabinet response spectrum (ICRS). A simple method and two rigorous methods are proposed in the EPRI NP-7146-SL guidelines for generating the ICRS. The simple method of EPRI can give unrealistic spectra that are excessively conservative in many cases. In the past, the time domain analysis (TDA) methods have been mostly used to analyze a structure. However, the TDA requires the generation of an artificial earthquake input motion compatible to the target response spectrum. The process of generating an artificial earthquake may involve a great deal of uncertainty. In addition, many time history analyses should be performed to increase the accuracy of the results. This study developed a numerical analysis program for generating the ICRS by frequency domain analysis (FDA) method. The developed program was validated by the numerical study. The ICRS calculated by FDA thoroughly matched with those obtained from TDA. This study then confirms that the method it proposes can simply and efficiently generate the ICRS compared to the time domain method.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.8
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• pp.90-97
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• 2013

In recent years, the many electric saving methods are studied because of difficulty of meeting the demand. The electric energy management such as monitoring of branch power consumption, demand control, metering, power quality monitoring, electric safety monitoring can make energy saving. The purpose of this paper is to develop a system which can provide the integrated management of various functions required for energy management by consumers. In this system all functions which were embodied into each devices are integrated into intelligent meter. The developed systems are tested and implemented by installing at consumer electric distribution panel.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.11
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• pp.2093-2102
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• 2010

In this paper, we introduce a fixer attaching robot system which is used to attach several fixers to a TV cabinet. It is necessary to automate the fixer attaching process for two reasons. One is that the process is very harmful because very strong ultraviolet rays are used in that process. The other is that the productivity and the overall quality of the end-product are determined by the fixer attaching process. We proposed 9 candidates for the robot system to be used in the fixer attaching process. Then we simulated cycle time for each of the 9 candidates with considering physical constraints. We also considered other aspects such as the easiness of implementation, possible interference with other mechanical structure, and cost etc. to choose one of the 9 candidates. We implemented the chosen robot system and adopted it in a TV manufacturing process.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.2
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• pp.75-84
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• 2010

An in-cabinet response spectrum should be generated to perform the seismic qualification of devices and instruments mounted inside safety-related electrical equipment installed in nuclear power plants. The response spectrum is available by obtaining accurate seismic responses at the device mounting location of the cabinet. The dynamic behavior of most of electrical equipment may not be easily analyzed due to their complex mass and stiffness distributions. Considering these facts, this study proposes a procedure to estimate the seismic responses of a structure by a combination of a test and subsequent analysis. This technique firstly constructs the modal equations of the structure by using the experiment modal parameters obtained from the impact test. Then the seismic responses of the structure may be calculated by a mode superposition method. A simple steel frame structure was fabricated as a specimen for the validation of the proposed method. The seismic responses of the specimen were estimated by using the proposed technique and compared with the measurements obtained from the shaking table tests. The study results show that it is possible to accurately estimate the seismic response of the structure by using the experimental modal parameters obtained from the impact test.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.731-732
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• 2005

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2200-2202
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• 2004

This paper deals with the design of the Control Cabinet in Control Rod Control System(CRCS), using a domestic Distributed Control System(DCS) developed to localize the instrumentation and control(I&C) system for nuclear power plant(NPP). There are many parts developed by domestic skill and being operated successfully in NPP, but the development of I&C system as an essential part has been slow in progress. We will show the great possibility of developing our own I&C system by applying this domestic DCS to nuclear I&C system and confirming its successful operation, in this paper.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.772-774
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• 1998

MMIS System of KNGR is composed of systems by using of digital equipment in general, and also interface function among systems is completed by a network. According to this, KNGR PCS also got rid of many kinds of interface cards which have been used for hardwired interface to outside system, and most of function in these cards is to be programmed by PLC. This paper defines the function and method which is to be programmed to PLC. And this paper presents new function which is to be added for operator's interface by using network. It is expected that PCS logic cabinet will be more simplified, satisfy KNGR design concept, and operation convenience will be increased.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1626-1627
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• 2007

This paper deals with the design and manufacturing of power cabinet for reactor power control system(PCS). The PCS provides the control signals and motive power to operate the CEDMs(Control Element Drive Mechanism). The CEDM is raise and lower the CEAs(Control Element Assemblies) in the reactor core. The CEAs are constructed with the Boron-10 isotope which has a high microscopic cross section of absorption for thermal neutrons. This characteristic causes the addition of negative reactivity when a CEA is inserted and positive reactivity when it is withdrawn from the reactor core.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.575-579
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• 2003

In this paper, we describe a Duplex Power Controller for Control Rod Control System(CRCS). A Duplex Power Controller has the various functions for the reliable operations of Control Rod Drive Mechanism(CRDM). Also we have implemented the diverse functions by utilizing the developed Duplex Power Controller. Due to the developed Duplex Power Controller, we are assured that the commercial operation by this system be made before long.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.50-55
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• 2018

Earthquakes are almost impossible to predict and take place in a short time. In addition, there is little time to take aggressive action when an earthquake occurs. Therefore, there are more casualties and property damage than with other natural disasters. Recently, earthquakes have been occurring all over the world. As the number of earthquakes increase, studies on the safety of structures are being carried out. On the other hand, there are few studies on the electric facilities, which are relatively non - structural factors. Currently, electrical equipment in Korea is often not designed for earthquake safety and is quite vulnerable to damage when an earthquake occurs. Therefore, in this study, modeling was conducted through ABAQUS similar to an actual cabinet panel and 3D dynamic nonlinear analysis was performed using a natural seismic. According to seismic zone I and normal ground rock conditions of the power transmission and transmission facility seismic design practical guide, the maximum response acceleration of the performance level was 0.157g. In this study, however, it was not safe to reach the limit state of 30% of the analytical result at 0.1g for the general cabinet panel. From the results, the seismic fragility curve was derived and analyzed. The derived seismic fragility curve is presented as a quantitative basis for determining the limit state of the cabinet panel and can be utilized as basic data in related research.