• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.3
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• pp.256-261
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• 2019

The use of military lithium batteries in this field accelerates the generation of internal pressure because the active materials, lithium and the electrolyte, react to form sulfur dioxide gas. This also reduces the amount of electrolyte. In this condition, batteries can 'vent' or 'explode' especially when completely discharged. Such venting and explosion can be regarded as a safety accident, as toxic gases and shrapnel are ejected from the batteries which can harm the user. A DTaQ was carried out in 2017 as a quality problem solution project to solve this safety issue. A protection circuit was thereby developed, which included a micro controller unit (MCU) which can stop battery usage when in an over-discharging state by sensing its low-voltage condition. In 2018, this concept was expanded to lithium batteries for the remote controlled ammunition system. This paper reports results of the improved performance.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1009-1011
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• 2002

Some defective cells in the battery bank of power systems using batteries result in deterioration of the performance of the total battery bank. Consequently, the battery bank can't perfectly back up the system in occurrence of any power problems and the overcharge of defective cells may lead to their explosion or the occurrence of fire. The developed battery management system in this study enables operators to telemeter and analyze internal resistance, voltages, currents, and temperatures of batteries at remote sites through a PC, so they can detect defective cells before the occurrence of power problems. And adoption of this system ensures extension of battery life.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.129-131
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• 1990

When insulating oil is flowed through a pipe, the electrostatic charge in the oil will be increased. Using inflammability oil, an electrostatic phenomena which may cause significantly problems as explosion must be circumvented by some methods. In this paper we made a new electrode which was applied AC field to the flowing oil for reducing electrostatic charge. Before we developed the new method of an electrostatic elimination, the electrification experiment was performed by using the same electrode which was supplied DC voltage to realize electrified conditions. As a result of this study, the effect of the electrostatic elimination could be observed.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.104-106
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• 2004

There are many under grounds facilities like oil pipes, gas pipes, water pipes, oil tanks, etc. and severe corrosion of these facilities made big problems. Fire, wide area water and soil pollution, massive and hazardous explosion, etc. can make big problems and cause big economical loss. So, various technologies were developed to keep these undergrouns facilities safely, and cathodic protection is one of it. For cathodic protection, one must detect potential of pipes, and there are so many test box to check pipes potentials. In this thesis, we describe on the development of small size corrosion monitoring system that measure pipes potentials easily and economically.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.6
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• pp.373-379
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• 2006

Vibration-based structural health monitoring is one of non-destructive evaluation (NDE) techniques for civil infrastructures. This paper presents a novel fiber optic accelerometer system to monitor civil engineering structures and a successful application of the novel sensor system for measuring ambient vibration of a real building structure. This sensor system integrates the Moire fringe phenomenon with fiber optics to achieve accurate and reliable measurements. The sensor system is immune to electromagnetic (EM) interference making it suitable for difficult applications in such environments involving strong EM fields, electrical spark-induced explosion risks, and cabling problems, prohibiting the use of conventional electromagnetic accelerometers. A prototype sensor system has been developed, together with a signal processing software. The experimental studies demonstrated the high-performance of the fiber optic sensor system. Especially, the sensor was successfully used for monitoring a real building on UCI (University of California Irvine, USA).

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.93-93
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• 2003

Tungsten and tungsten heavy alloys have widespread application as radiation shielding devices and heavy duty electrical contacts. High density and good room temperature mechanical properties have generated interest in evaluating tungsten and tungsten alloys as kinetic energy penetrators against armor. Nowdays ultra fine-grained tungsten powders are in great interest because higly dense structures can be obtained at low temperature, pressure and lower sintering time. Several physical md chemical methods are available for the synthesis of nanometric metal Powders: ball milling, laser abalation, vapor condensation, chemical precipitation, metallic wire explosion i.e. However production rates of the above mentioned methods are low and further efforts are needed to find out large-scale synthesis methods. From this point of view solid state combustion method ( known as SHS) represents undoubted interest.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1749-1751
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• 1998

Close to high power radio/radar transmitters there is a possibility that sparks may be occur at discontinuities in metallic structures. If these structures are in an area in which a flammable mixture may be present, there is a possibility that a fire or explosion may be caused by the sparking. A number of assessment procedures for quantification of the hazard have been produced. This paper reviews the bases of the British Standard covering ignition hazards by radio-frequency radiation and presents some ignition test apparatus to access these hazards.

• Proceedings of the KIEE Conference
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• 1999.11c
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• pp.618-620
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• 1999

The owner of metallic structures has a burden of responsibility for the protection of corrosion and the prevention against big accident such as gas explosion or collapse of bridge and building and so on. So, he has been spent the money and the time for corrosion monitoring and analysis of measuring data. Therefore, KERI(Korea Electrotechnology Research Institute) has developed the real-time wireless remote corrosion monitoring system using by TRS(Trunked Radio System). The results of development for corrosion monitoring system are described briefly. Especially, the interfacing technology between the server and rectifier introduced in this paper.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.192-194
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• 2005

Acceptance of the international standards for video compression, such as H.261, MPEG-1 and MPEG-2, along with the developments in video codec hardware, has created an explosion of application. Among these, the long time quest for long-distance digital video transmission causes an increasing interest in transporting compressed video over networks which are nontraditional for this purpose, including asynchronous transfer mode networks, the Internet, and cellular and wireless channels. Transmission of compression video over packet network is improved for error resilience. And layered video coding techniques improves error resilience. We present a efficient method of scalable video coding for low bandwidth.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1513-1514
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• 2015

전력설비가 열화, 서지에 의해 절연이 파괴되었을 경우 밀폐기기 경우 폭발, 화재를 일으킴으로써 일반인에게 피해를 입히거나 인근 설비로 파급이 확대될 가능성이 있다. 최근 전력설비는 대용량화 추세인 반면 콤팩트 사이즈를 요구하고 있어 절연문제로 인한 폭발 가능성은 더욱 커지고 있다. 이러한 전력설비의 폭발을 방지하고 피해확대를 줄이기 위해 방압변, 순간압력상승 방지장치 등이 설치되고 있으나, 예방에는 한계가 있다. 이에 최근, 국외를 중심으로 전력기기 특히, 지상설치기기의 안전성 확보를 위해 고속투입 접지스위치(Arc Eliminator)를 개발하여 설치 의무화를 고려하고 있다.