• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.563-568
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• 1999

Generally the control method of wire feeding motor in welding machine has been used full-wave phase control method. The fire-angle control generates low frequency speed ripple, and it causes the output current ripple. So it results in the variation of welding condition and low welding performances such as spatter generation and bead state. For the purpose of welding performances improvement by speed controller in wire feeding motor, in this paper the constant speed control method for welding machine is proposed. The proposed system is composed of speed control loop and current control loop. As a result of experiment by using proposed constant wire feed experiment by using proposed constant wire feed speed controller, the output voltage and current waveform and metal transfer are maintained stably. And moreover the number of instantaneous short circuit occurrence is reduced remarkably.

• 한국재난정보학회 논문집
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• 제4권1호
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• pp.34-52
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• 2008

The result of all terrors causes enormous damage. In order to prevent this damage in advance and find a prompt provision after terror, we investigated a safety measure against terror on the assumption that the fire in Daegu central subway is a subway terror. The followings are the safety measures against terror based on an underground space. Frist, training systems have to be established to provide against a terror. Second, People's consciousness about safety from a terror, centering on early education, has to be raised. Third, the provisions related with underground tunnel have to be established so that people can take shelter in underground tunnel areas. Fourth, CCTV has to be established in the guest rooms of the electric motor cars. Last, cooperative systems among related organizations have to be constructed, and the networks of the organizations have to be established so that they can cope with an accident.

• 산업기술연구
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• 제24권A호
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• pp.83-90
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• 2004

Generally, electronic appliances are used on the basis of normal power source supply. The power source inevitably includes the abnormal condition, such as, sudden voltage sagging, power interrupt, and induced noises. As the electronic appliances which include micro-controller-based circuits are being increased recently, the controller circuit sometimes malfunctions by the abnormal condition of the power source. This situation causes serious problems such as hitch of electric appliance, fire and medical instrument glitch, which produces serious situations. In this paper, development of power interrupt tester which is highly suitable for an endurance test device under abnormal power source to microprocessor-based circuits is proposed 89C2051 microcontroller is performed to make power interrupt signal, and software controls peripheral hardwares and built-in functions. Experimental results of this study will offer a good application to electronic appliance maker as a test device of hardware and software debugging use.

• Nuclear Engineering and Technology
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• 제51권1호
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• pp.317-324
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• 2019

A high energy arcing fault event occurred in the medium-voltage (13.8 kV and 4.16 kV) metalclad switchgears in a nuclear power plant not only affecting switchgear but also connected equipment due to the arc energy. The high energy arcing fault also causes a fire that influences the safety function of the unit. Therefore, from the safety point of view, it is necessary to evaluate the influences of high energy arcing fault events on the safety functions of nuclear power plants. The purpose of this paper is to elaborate the characteristics of high energy arcing faults and propose a high energy arcing fault mitigation scheme for medium voltage networks in nuclear power plants.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.98-100
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• 2007

DC Arc Fault Current is an electric discharge which is occurred in two opposite electrode. In this paper, DC arc detection device is designed for the display of DC arc fault current which is occurred in the local electric network with DC Power. This DC arc is one of the main causes of electric fire. Arc fault in electrical network has the characteristics of low current, high impedance and low frequency. DC Arc current detection device is designed for the display of arc fault current which has the modified arc characteristics.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.471-477
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• 2009

This study investigated automatic malodor exhaust ventilating methods in a water closet system. Even though these days advanced equipment has been applied into the toilet in a building or house, the odor due to the evacuating the bowels should be carefully removed to maintain clean and pleasant toilet. Therefore, this study thoroughly considered the main causes of the malodor problems and suggested the best applicable methods to the closet system.

• 셀메드
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• 제10권2호
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• pp.10.1-10.5
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• 2020

Ayurveda is the science of life. It guides about the protection of health of the healthy and alleviation of ailments of diseased person. In Ayurveda Upavasa (fasting) is one among all Daivavyapashraya (spiritual) therapies and one among ten Langhana (that which produces lightness of the body) therapies. It is also stated in Ayurveda that fasting increases digestive fire and causes digestion of Ama-dosha (metabolic toxins). On religious grounds, Upavasa is a way to get closer to the almighty. Scientists have found fasting activates autophagy. Yoshinori Ohsumi, a Japanese cell biologist won the Nobel Prize in Medicine in 2016 for his research on how cell recycle and renew their content, a process called autophagy. Many published studies indicate positive effects of fasting on neuroprotection and longevity.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권6호
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• pp.255-260
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• 2006

Arc Fault Current is an which occurrs in two opposite electrode. In this paper, arc current control algorithm is designed for the interruption of arc fault current which is occurred in the low voltage network. This arc is one of the main causes of electric fire. General arc current sensor has troubles for detecting arc currents, thus we would like to propose the arc current detection method without current sensor. In this parer, arc discharge currents within power lines are being detected through the arc current control algorithm.

• 한국안전학회지
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• 제32권3호
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• pp.21-27
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• 2017

Even if several chemical accident prevention systems such as PSM(Process Safety Management), RMP(Risk Management Plan), etc. have been carried out, many chemical accidents have still occurred at industrial plants in Korea. We describe the status of chemical industry and the trend of occurrence of chemical accidents in Korea. And this paper analyzes the recent chemical accidents in eight ways. These ways include chemical accident forms, ignition sources, sources of chemical equipment, human vs equipment/material causes, worker's working situation, employee scale, hazardous substances, week & time, fatalities of manufacture & contractor's workers. Finally we proposes the four representative prevention measures brought to result of cause analysis by accident statistics.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.48-49
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• 2018

Recently the old buildings have been increasing and increasing reconstruction. As a result, the frequency of use of architectural adhesives has increased. Adhesives are not only used for bonding but also for building materials used in various fields. However, since the adhesive is made of an organic material, it causes various skin diseases and sick house syndrome, and when a fire occurs, harmful substances are generated, and incomplete combustion may cause personal injury. Therefore, in this study, to solve the disadvantages of conventional adhesives, we tried to develop inorganic adhesives using inorganic materials.