• The KIPS Transactions:PartB
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• v.18B no.4
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• pp.213-220
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• 2011

This paper proposes an effective, four-stage smoke detection method based on video that provides emergency response in the event of unexpected hazards in early fire-alarming systems. In the first phase, an approximate median method is used to segment moving regions in the present frame of video. In the second phase, a color segmentation of smoke is performed to select candidate smoke regions from these moving regions. In the third phase, a feature extraction algorithm is used to extract five feature parameters of smoke by analyzing characteristics of the candidate smoke regions such as area randomness and motion of smoke. In the fourth phase, extracted five parameters of smoke are used as an input for a K-nearest neighbor (KNN) algorithm to identify whether the candidate smoke regions are smoke or non-smoke. Experimental results indicate that the proposed four-stage smoke detection method outperforms other algorithms in terms of smoke detection, providing a low false alarm rate and high reliability in open and large spaces.

• Journal of the Korean Geotechnical Society
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• v.26 no.10
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• pp.27-38
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• 2010

In every summer season, most of the slope failures and debris flows occurr due to seasonal rain, typhoon, and localized extreme rainfall in Gangwon Province where 83% of the area is of mountain region. To investigate the slope-hazard triggering rainfall characteristics in Gangwon Province, slope hazard data, precipitation records, and forest fire data were collected and the DATABASE was constructed. Analysis results based on the DATABASE showed that many slope hazards occurred when there was little rainfall and the preceding rainfall had more effect on the slope hazard than the rainfall intensity at the day of hazard. It also showed that the burned area by forest fire was highly susceptible to slope hazard with low rainfall intensity, and the slope hazard in burned area showed highest frequency, especially, under the rainfall below 2-year return period.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.04a
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• pp.468-475
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• 2001

It can be seen through the previous earthquake damages that indirect damages such as those by fire are much greater rather than direct (firsthand) damage by earthquakes. Recently, gas is used very popularly all over the country but no measures have been taken against hazards (or dangers), for instance, such as fires caused by leaking gas pipes when earthquakes occur. Earthquake-Actuated Automatic Gas Shutoff Devices (Shutoff Device) are used to prevent such disaster in other countries. ChungJung Engineering. Co. is making a sample of a Shutoff Device for the first time in Korea. In this study, a derivation of mathermatical model and the important effects of various variables on the shutoff device are mentioned.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.8
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• pp.405-411
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• 2000

When faults occur in transmission lines, the classification of faults is very important. If the fault is HIF(High Impedance Fault), it cannot be detected or removed by conventional overcurrent relays (OCRs), and results in fire hazards and causes damages in electrical equipment or personal threat. The fast discrimination of fault needs to effective protection and treatment and is important problem for power system protection. This paper propolsed the fault detection and discrimination algorithm for LIFs(Low Impedance Faults) and HIFs(High Impedance Faults). This algorithm uses artificial neural networks and variation of 3-phase maximum currents per period while faults. A double lines-to-ground and line-to-line faults can be detected using Neural Network. Also, the other faults can be detected using the value of variation of maximum current. Test results show that the proposed algorithms discriminate LIFs and HIFs accurately within a half cycle.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.208-210
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• 2009

본 논문에서는 비닐절연코드의 기계적 피로에 의한 소손패턴과 화재위험성에 대하여 실험, 분석하였다. 비닐절연코드는 2중의 절연피복으로 되어 있으며 도체는 여러 가닥의 소손들로 구성되어 있다. 비닐코드는 반복적인 구부림이나 인장등 기계적 피로에 의해 피복 내 도체가 손상을 입게 되며 전기가 흐르고 있는 상태에서 끊어진 소선들이 접촉과 끊어짐을 반복함으로써 아크와 열이 발생하며 이때 발생한 마크와 열에 의해 피복이 탄화되어 결국에는 착화됨을 볼 수 있었다. 이러한 기계적 피로에 의한 국부 발열과 화재 예방을 위한 기술개발이 필요한 것으로 사료된다.

• Biomedical Science Letters
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• v.23 no.3
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• pp.155-160
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• 2017

Biomedical laboratory is full of risks. Risk could be biological, chemical, radioactive, mechanical, physical, fire and electrical. All possible risks need to be identified, evaluated and controlled. A risk management system must be in place to prevent accident or loss of lives and to improve overall workplace safety and productivity. Safety in laboratory is a combination of appropriate risk management system, engineering controls and technical facilities, administrative controls and safety procedures and practices. Laboratory safety culture must be developed so that exposure to hazards for laboratory personnel, community and environment will be minimized or eliminated. In this review, importance of safety in a biomedical laboratory and risk management will be discussed.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.30-35
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• 1996

Accumulations of worn-out automobile tires creat fire and health hazards. As a possible solution to the problem of scrap-tire disposal, an experimental study was conducted to examine the potential of using tire chips as aggregate in rubber mortar. This paper examines strength and toughness properties of rubber mortar in which different amounts of rubber-tire particles of several sizes were used as aggregate. The rubber mortar mixtures exhibited lower compressive, bending, tensile than did normal mortar. However, these mixtures did not demonstrate brittle failure, but rather a ductile, plastic failure, and had the ability to absorb a large amount of plastic energy under compressive loads.

• Journal of the Korean Institute of Gas
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• v.15 no.4
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• pp.44-50
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• 2011

Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower explosion limit(LEL) and upper explosion limit(UEL) of ethers were predicted by using the heat of combustion and stoichiometric coefficients. The values calculated by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other flammable ethers.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.589-599
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• 2016

Korean wooden cultural heritages are treated by flame retardants to protect fire hazards. Two types of flame retardants are used to treat wooden cultural heritage. These flame retardants cause some problems such as surface whitening, discoloration, and cracks due to the chemical reaction caused by Korean traditional wood painting (Dancheong), flame retardant and wood humidity. The Korean government is trying to cut down on the amount of flame retardants for the wooden cultural heritage because of these problems. This study was carried out to find the cause of whitening by flame retardants treatment. The reaction between pigment and flame retardant chemicals was analyzed by infrared spectroscopy.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.252-254
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• 2001

Accurate detection and classification of faults on transmission lines is vitally important. High impedance faults(HIF) in particular pose difficulties for the commonly employed conventional overcurrent and distance relays, and if not detected, can cause damage to expensive equipment, threaten life and cause fire hazards. Although HIFs are far less common than LIFs, it is imperative that any protection device should be able to satisfactorily deal with both HIFs and LIFs. This paper proposes an algorithm for fault detection and classification for both LIFs and HIFs using Adaptive Network-based Fuzzy Inference System(ANFIS). The performance of the proposed algorithm is tested on a typical 154[kV] Korean transmission line system under various fault conditions. Test results show that the ANFIS can detect and classify faults including (LIFs and HIFs) accurately within half a cycle.