• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.11
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• pp.1931-1936
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• 2016

In this paper, we analyzed causes of accidents that recently increased in the illegal and defective LED lamps. They were analyzed by the electrical characteristics calculation and reappearance experiments. The causes of the accidents were analyzed from the circuit affected by the variation of voltage, current and power by harmonics. We drew a conclusion for electrical safety in illegal or degraded LED lamps from the analysis result. The management factors for electrical safety in LED lamps were harmonics, reactive power and power factor. It is possible to secure the electrical safety through monitoring of power factor in failure products and available in smart meters or smart distribution boards.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.835-841
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• 2007

The followings are concluded from the treatment of headache in Hyungsang medicine, focussed on 11 kinds of headaches in Donguibogam. Headache is classified into overall headache and migraine according to the affected region. The causes are divided into exogenous affection and internal injury; The former brings on headache due to Wind-Cold and headache due to Damp-Heat. The latter, reversal headache, headache due to adverse rising of phlegm, headache due to regurgitation of Gi, headache due to excessive Heat, headache due to excessive Damp, true headache, and alcoholic headache. Headache due to internal injury generally tends to show deficiency syndrome with external affection. Headache due to exogenous affections is common to those who have big head or white skin and to Bangkwang type, and woman. The primary causes are Wind-Cold and Wind-Heat. When the body is observed in the perspective of eight phases, Damp-Heat is to be produced in the front, and Dry-Damp, in the back. Headache due to Damp-Heat is susceptible to Yangmyeong meridian type whose body develops more in the front and to woman. In the perspective of the upper and the lower, Yangdu(that is, head) is related to Eumdu(that is, glans of penis). Headache is also caused by the problems of Eumdu ,such as deficiency of Essence in man, pathologic change of uterus in women, and San syndrome in lower abdomen. In the case of man, headache is frequently severe and difficult to treat because head is a root for man. Disharmony of Gi and blood between the right and the left brings out migraine and headache due to regurgitation of Gi. Migraine is usually accompanied by symptoms of exogenous affection and often afflicts Gi-type, Shin-type, Soyang meridian type, deer type, and Dam-type. Headache due to regurgitation of Gi is brought by Gi deficiency or blood deficiency so that symptoms of exogenous affection do not show. It is mainly common with old people and those who have sunken eyes induced by deficiency of stomach Gi. In the perspective of the upper, the middle, and the lower, the pathologic change of head, chest and abdomen also bring about headache. The pathologic cause of head is Wind-Heat ,which triggers overall headache, migraine, headache due to Wind-Cold, headache due to excessive Heat, The pathogen of chest is phlegm-Fire and brings out headache due to Damp-Heat and headache due to adverse rising of phlegm. The pathologic factor in abdomen is Cold-Damp and produces headache due to adverse rising of phlegm and headache due to excessive Damp. In case of women, headache is generally caused by phlegm-Fire and retention of undigested food.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.29-30
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• 2023

Wood is a construction material that has the advantages of carbon dioxide storage ability, noise reflection, and eco-friendliness. In order to use wood for a long time, you must use wood-specific paint, which is called oil stain. Oil stain improves water resistance and moisture resistance, but has the disadvantage of being weak against fire. This is because the oil contained in the oil stain causes a chemical reaction, and this chemical reaction causes the oil stain to spontaneously ignite, igniting nearby combustible materials and causing frequent fires. To improve this, in this study, different flame retardants were mixed and added to oil stain to produce functional oil stain. In addition, we would like to apply it to wood to check glow time and carbonization area. As a result of the experiment, it shows the best performance when mixed at 30(15 + 15)(%) and added to oil stain. The remaining burn time is satisfied from 10% for all samples, and the carbonized area is satisfied when it is 30%.

• Journal of the Korea Institute of Building Construction
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• v.21 no.5
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• pp.483-493
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• 2021

Urban overcrowding has created an explosive supply and demand for high-rise buildings. High-rise buildings are contributing to enhancing the image of the city by serving as focal points, but due to the stack effect, malfunction of elevator doors, difficulties in opening and closing the doors and windows of the outer wall, smoke and odors spreading to the upper floors, noise, energy loss, fire and pollutants have been causing various unexpected problems such as rapid spread of fire. This study classified high-rise buildings according to their vertical zoning, analyzed the causes of and solutions to the stack effect, and derived design and construction methods. Through the initial plan to block the outside air and securing airtightness through precise construction, we sought ways to secure the airtightness inside and outside the building by actively blocking the airflow from the lower floors. In addition, the facility solution can be a measure to reduce the specific phenomena caused by the stack effect, but it should only be applied to the minimum extent because the potential for secondary damage is high. This study emphasized the need for systematic stack effect management by suggesting design and construction measures for each vertical zoning of the causes and countermeasures of the stack effect. It is expected that this study will be helpful not only for design and construction, but also for building maintenance.

• The Journal of Korean Medical History
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• v.22 no.1
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• pp.57-67
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• 2009

The results of analyzing "Shanghanlun-Shanghan examples" of Song Dynasty Text and Liuwansu's writings in the pursuit of comprehending his views written in "Fire-Heat" & "Warm disease" -are as follow. 1.He introduced Exterior-Interior Shanghan and Latent in the Winter & recurrent in the Spring Shanghan concept in the Febrile disease pathology as the link and the bifurcation point. His perception on Febrile disease encompassed Shanghan and Febrile disease on the same plane but actually discriminated in the treatment and medication between the two actually. 2.He suggested Febrile disease pathology in the concept of Shanghan and Febrile disease, which is coherent in the formation of interior heat as the result of the invasion of the lung by warm pathogen described in Warm disease Wei, Qi, Ying and Xue Fen Syndrome differentiation. He expanded the concept of esoteric portal 玄府 of "Suwon Tiaojinglun", to that of the omni-present portal & way of Qi's all directions movement, which is in accordance of invasion of upper energizer 上焦 by warm or hot pathogen via mouth and nose as used in Warm disease three-energizer differentiation. 3.He recognized both exterior-interior febrile disease in the context of both exterior-interior contact cause disease. He prescribed pungent-cool exterior releasing medicinal similar to that of exterior-releasing treatment adopted in warm disease. As lily-talc powder百合散 introduced in "Golden chamber synopsis" dispells heat by promoting excretion of urine and defecation, it is regarded as the original formula of later ikwonsan yiyuansan 益元散.

• Korean Journal of Remote Sensing
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• v.36 no.1
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• pp.29-39
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• 2020

Forest fire is a critical disaster that causes massive destruction of forest ecosystem and economic loss. Hence, accurate estimation of the burned area is important for evaluation of the degree of damage and for preparing baseline data for recovery. Since most of the area size damaged by wildfires in Korea is less than 1 ha, it is necessary to use satellite or drone images with a resolution of less than 10m for detecting the damage area. This paper aims to detect wildfire-damaged area from a Kompsat-3 image using the indices such as NDVI (normalized difference vegetation index) and FBI (fire burn index) and to examine the classification characteristics according to the methods such as Otsu thresholding and ISODATA(iterative self-organizing data analysis technique). To mitigate the salt-and-pepper phenomenon of the pixel-based classification, a gaussian filter was applied to the images of NDVI and FBI. Otsu thresholding and ISODATA could distinguish the burned forest from normal forest appropriately, and the salt-and-pepper phenomenon at the boundaries of burned forest was reduced by the gaussian filter. The result from ISODATA with gaussian filter using NDVI was closest to the official record of damage area (56.9 ha) published by the Korea Forest Service. Unlike Otsu thresholding for binary classification,since the ISODATA categorizes the images into multiple classes such as(1)severely burned area, (2) moderately burned area, (3) mixture of burned and unburned areas, and (4) unburned area, the characteristics of the boundaries consisting of burned and normal forests can be better expressed. It is expected that our approach can be utilized for the high-resolution images obtained from other satellites and drones.

• Journal of the Korean Society of Safety
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• v.29 no.4
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• pp.48-53
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• 2014

This study is analyzed for electrical fire danger by electric equipments through surveys of stable owners and the field investigation at 64 stable. Also, an experiment is performed to analyze the thermal characteristics of 4 types electric wiring according to the number of operating halogen warm lamp group and automatic waterer group in Beon-young stable in the Cheongwon location. The survey is done to investigate the occurrence of electrical fire, electric equipment, causes and dangerous equipment. As a result, halogen warm lamp group and automatic waterer group are found to have dangerous loads. In the field investigation, the mode of load capacity of the halogen warm lamp group and automatic waterer group was investigated. The mode of load capacity of halogen warm lamp group (over 3 years) is found 17A and that of the auto waterer group (10 years) is 16A. In this experiment, the halogen warm lamp group aged at least 3 years showed $109^{\circ}C$ while that aged less than 1 year appeared $83^{\circ}C$, showing the max gap of $26^{\circ}C$. The automatic waterer group aged 10 years showed $90^{\circ}C$ while that aged less than 1 year appeared $68^{\circ}C$, showing the max gap of $22^{\circ}C$. These findings indicate that the mode of load capacity needs to be considered in selecting and installing wiring for the electric equipment construction of halogen warm lamp group and automatic waterer group in stable.

• Journal of the Korea Safety Management & Science
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• v.23 no.4
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• pp.23-29
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• 2021

The purpose of this study is to reduce the probability of occurrence of electric fires as a preemptive preventive measure, and to strengthen the capability of preventing electric fires by strengthening the cooperative function between electric fire-related departments and establishing a cooperative system. In this study, the general aspects of electric fires were identified by reviewing the literature such as ignition mechanisms of electric fires. And the major electrical fires that occurred in the last 10 years were classified into ignition factors (short circuit, overload/overcurrent, and earth leakage/ground fault) and ignition sources (wiring/wiring appliances, electrical equipment/household appliances). And the 4M technique was used to analyze the potential causes of ignition at the fire site and to suggest preventive measures. In the case In this study, out of 48 electrical fires in the past 10 years, 16 short-circuit fires, 3 overload/overcurrent fires, 3 short-circuit and earth fault fires, 16 fires in wiring/wiring appliances, and 10 fires in electrical equipment/home appliances classified as cases. And prevention measures were presented in terms of human, machine, media, and management by using the 4M technique. For the preemptive prevention of electric fires, strengthening the compulsory electrical safety inspection and making it mandatory to report when new or expanding electric facilities, charging a fee for electric safety inspection for detached houses and granting benefits subject to inspection completion, improvement of the electric safety voluntary inspection table and safety indications; It was suggested as a policy to organize and operate electrical safety inspection personnel in a two-person team (mixed), establish a close work cooperation system with related organizations, and strengthen electrical safety education and publicity.

• Journal of Korean Society of Rural Planning
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• v.21 no.4
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• pp.157-165
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• 2015

The purpose of this study is on identifying charactreistics and management direction of complementary pond of Dalmaji village in Gangjin. Accordingly, this village was indicated as Experience and Resort village by Korean government. This study describes the construction background and characteristics and identifies species diversity and characteristics through field survey. For this, literature and field survey was performed. In field survey, vegetational survey was performed in Aug. of 2015. D(Dominant degree) and S(Sociability degree) was measured by Brown-Blanquet's method. The answer was searched from Myungsanron(明山論), a textbook of Fengsui(風水) in Joseon dynasty. Of these causes, it was considered that the representative one is a protection of fire and infectious disease because the Wolgak mountain is a fire mountain(火山) as a stone mountain in Fengsui. The results demonstrate decline of aquatic ecosystem because of neglect management. The total number of species was 24. Of the species, Zelkova serrata is a natural vegetation of this complementary forest. This is nominated as Lagerstroemia indica and Camellia japonica community. Species composition demonstrate the characteristics of Korean southern region as mixed forest of evergreen trees and deciduous ones which are indigenous plants. It was considered Juniperus chinensis KaizukaVariega in central round island was planted in Japanese colonial period and it have to be removed. It was considered that name of moon pond and moon island etc. projects the mind of village ancestors which are going to reach an ideal condition of moon. And management of quantity and depth of pond water was critical for restoration of disappearing lotus from related literature. Periodic management was needed for ecological structure and function improvement because of ecological disturbance by the invasive plants like Humulus japonicus.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.5
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• pp.423-430
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• 2009

Recently as the inactive response characteristics of the existing RCD used on low voltage power distribution system, so control of overload and electric short circuit faults, major causes of electrical fires, are not enough. Therefore, this paper confirms the unreliability of the existing RCD by electrical fault simulator and proposes a EFDPD by using semiconductor switching devices and a high precision current sensor (namely, reed switch) for the prevention of electrical disasters in low voltage power distribution system caused by overload or electric short circuit faults. The sensitive reed switch in the proposed EFDPD exactly detects the increased magnetic flux with the overload or the short current caused by a number of electrical faults, and the following, the self circuit breaker in EFDPD rapidly cuts off the system. The proposed EFDPD confirms the excellent characteristics in response velocity and accuracy in comparison with the conventional circuit breaker through various operation performance analysis. The proposed EFDPD can also prevent electrical disasters, like as electrical fires, which resulted from the malfunction and inactive response characteristics of the existing RCD.