• Journal of the Korean Society for Railway
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• v.6 no.4
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• pp.232-238
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• 2003

A health monitoring system becomes a very useful tool to obtain information on long term behavior of the important railway structures such as very long span and special type bridges. It can be also used to give a warning signal to the maintenance engineer when the structure shows abnormal behavior. However, due to long term use and temperature changes, the health monitoring system needs to be calibrated periodically. In this study, calibration and gauge factor readjustment process made for the health monitoring system installed in the railroad bridges and tunnel are reviewed and a few findings are updated. Future work will be concentrated on the long-term analysis of the measurement data and on the database structures so that the assessment of the structure is possible

• Proceedings of the Korea Society for Simulation Conference
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• 2003.06a
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• pp.67-71
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• 2003

In order to manage a cluster system that consists of a number servers, management aspects such as configuration management, fault management, performance management, and user management should be considered. Especially, it is necessary to monitor performances for performance and fault management. An agent in each server collects performance counters, status changes, and events occurred in normal or abnormal states. The data collected are delivered to a collector sorter and processed in a report tool for performance analysts and management decision in the cluster system point of view, by detecting fault state and tracing out resource usage, service response, and response, and states until failed. In this paper we propose an architecture modeling of a performance report tool for proactive cluster system management. Some results on a cluster system are presented.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.10
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• pp.33-41
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• 2010

There are several overvoltages by abnormal conditions in power system. We need to calculate these ovevoltages for the insulation design and the fault analysis. For these calculations, we used EMTP(Electro-magnetic Transients Program). During EMTP calculations, the accurate modelling of the equipments is very important for analysis results. In this paper, we considered the effects of the modelling condition's changes for transmission line within EMTP modelling cases of overvoltage analysis. Specially, we considered CB closing cases of 765[kV] system. So, we had changed the calculation frequencies of Line Constants, which is used for CB closing cases. In addition, we compared the calculation result and the measured result.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.5
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• pp.838-844
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• 2015

Latest development of ICT makes building, including houses, factories and public facilities, more intelligent and automatized. It follows that a wide variety of electric and ICT installations are adopted along with micro electronic equipments. Corresponding to such changes, the frequency of lightning increases due to the abnormal climate. The major damage by lightning surge is disconnection and malfunction of facilities. It is necessary, therefore, to make a regulation of inspection and maintenance for lightning protection facilities. This paper deals with main issues of a regulation draft of inspection and maintenance for lightning protection facilities based on IEC 62305

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.4
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• pp.582-588
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• 2008

Microgrids are new distribution level power networks that consist of various electronically-interlaced generators and sensitive loads. The important control object of Microgrids is to supply reliable and high-quality power even during the faults or loss of mains(islanding) cases. This paper presents power control methods to coordinate multiple distributed generators(DGs) against abnormal cases such as islanding and load power variations. Using speed-droop and voltage-droop characteristics, multiple distributed generators can share the load power based on locally measured signals without any communications between them. This paper adopts the droop controllers for multiple DG control and improved them by considering the generation speed of distribution level generators. Dynamic response of the proposed control scheme has been investigated under severe operation cases such as islanding and abrupt load changes through PSCAD/EMTDC simulations.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.441-444
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• 2004

Each electrical apparatus radiates various infrared as the condition of surface and load current. Because heat distribution of the apparatus changes as the condition, it is able to analyze the condition of the apparatus by using the distribution. However, methods having been used to measure the heat distribution cannot compare normal condition with abnormal, and the apparatus has diagnosed by intuition. This paper deal with a program that is able to analyze changed temperature distribution. The program is to analyze temperatures on pixels in selected region of interest or position and is able momently and logically to analyze condition of the apparatus. The results are able to apply to a on-line monitoring system.

• The Journal of Internal Korean Medicine
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• v.22 no.2
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• pp.175-181
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• 2001

Objectives : This study was undertaken to study the action mechanism of Rhizoma Davalliae (RD) at parameter related to regulating bone density. Methods : We measured alkaline phosphatase activity and the contents : calcium, hydroxyproline, osteocalcin, calcitonin, and parathyroid hormone after the ovariectomized rats had been treated with RD for 30 days. Results : The following changes occurred: First, the serum calcium content and the calcitonin content, which decreased in ovariectomized rats, increased with RD treatment. Second, the serum alkaline phosphatase activity, the parathyroid hormone ativity, the osteocalcin content, the urinary calcium content, and the hydroxyprolin content-which increased in ovariectomized rats-decreased with RD treatment. Conclusions : These results show that RD treatment can recover abnormal calcium metabolic process by sex hormone inequality, promoting bone formation and inhibiting bone absorption.

• Toxicological Research
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• v.5 no.2
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• pp.111-121
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• 1989

Subacute toxicity of Hantabax, epidemic hemorrhagic fever vaccine, was investigated in ICR mice with subcutaneous injection. Any significant toxic symptom was not observed in the treated mice during the experimental period. Macroscopic examination on the organs of tested animals showed no abnormal findings. On autopsy, no significant changes were found in all organs examined.

• Toxicological Research
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• v.5 no.2
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• pp.123-133
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• 1989

Subacute toxicity of Hantabax, epidemic hemorrhagic fever vaccine, was investigated in Sprague-Dawley rats with subcutaneous injection. Any significant toxic clinical symptom was not observed in the treated rats during the experimental period. Macroscopic examination on the organs of tested animals showed no abnormal findings. On autopsy, no significant changes were found in organs examined.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.204-204
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• 2002

Alcohol drinking during pregnancy can result in abnormal fetal development including fetal alcohol syndrome (FAS). The molecular mechanisms of FAS, however, is not completely elucidated. In the present study, we evaluated the developmental toxicity of ethanol and its metabolite, acetaldehyde using post implantation whole embryo culture and determined changes of gene expression by ethanol treatment by cDNA microarray.(omitted)