• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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• pp.72-75
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• 2003

Effects of delay and panel temperature on the discharge time lag and the controllability of weak discharge mode were studied under single cell driving circumstances of ac PDP. It was found that sufficient number of priming particle is necessary for inducing weak discharge in ramp voltage driving. Discharge time lag was reduced dramatically under elevated panel temperature condition It is speculated that decrement of discharge time lag at the high temperature is related to the reduction of diffusion loss of charged particles during the after glow.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1998년도 제17회 KOSCI SYMPOSIUM 논문집
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• pp.69-77
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• 1998

In order to meet the stringent emission regulations, fast light-off of a catalyst is essential to reduce the HC and CO emissions during cold start. Cranking Exhaust Gas Ignition (CEGI) method developed in this study showed that the catalyst reaches the light-off temperature in a few seconds after cold start. The CEGI system cuts off the ignition signal for a few seconds during the cranking period. so the unburned fuel-air mixture bypasses the combustion chamber and flows through the exhaust manifold. When the unburned mixture reaches two glow plugs installed upstream of the catalyst, it burns and releases the thermal energy to heat up the catalyst. Results from the FTP-75 tests showed that the exhaust emissions with the CEGI reduced by 47.7% for THC and by 88.6% for CO in the cold-transient phase of the test.

• 한국표면공학회지
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• 제50권6호
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• pp.504-509
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• 2017

In order to improve corrosion resistance for cast stainless steel in seawater, the characteristics of corrosion resistance after plasma ion nitriding was investigated. Plasma ion nitriding process was conducted in a mixture of nitrogen of 25% and hydrogen of 75% at substrate temperature ranging from 350 to $500^{\circ}C$ for 10 hours using pulsed-DC glow discharge plasma with working pressure of 250 Pa in vacuum condition. Corrosion tests were carried out for as-received and plasma ion nitrided specimens. The corrosion characteristics were investigated by measurement of weight loss and observation of surface morphology. In anodic polarization experiment, relatively less damage depth and weight loss were presented at a nitrided temperature of $400^{\circ}C$, attributing to the formation of S-phase.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 C
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• pp.1686-1688
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• 2003

Effects of delay and panel temperature on the discharge time lag and the controllability of weak discharge mode were studied under single cell driving circumstances of at PDP. It was found that sufficient number of priming particle is necessary for inducing weak discharge in ramp voltage driving. Discharge time lag was reduced dramatically under elevated panel temperature condition. It is speculated that decrement of discharge time lag at the high temperature is related to the reduction of diffusion loss of charged particles during the after glow.

• Journal of the Korean Wood Science and Technology
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• 제40권5호
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• pp.311-318
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• 2012

This study investigated the flame retardant performance of developed four types of flame retardant chemicals (FRC), FRC-A, B, C and D. Four kinds of soft wood species, Sugi (Cryptomeria), Spruce (Picea abies), Hinoki (Chamaecyparis obtusa) and Korean pine (Pinus koraiensis), were used. The wood specimens were treated by spreading the FRC on the surface with different quantities, 30, 50, 70, 90, 110 g/$m^2$, respectively. The charred area, charred length, after flame time and after glow time were tested. And their suitabilities as incombustible materials were evaluated. The specimen treated by FRC-D showed better incombustible properties than others, even though with lower quantity. Therefore it is supposed that the FRC-D could be able to be applied on the cultural heritage, such as Korean wooden house for preventing fire.

• 한국입자에어로졸학회지
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• 제9권1호
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• pp.31-36
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• 2013

In this study, Mo metal powder was prepared by hydrogen reduction of Mo trioxides with different purity of 2N and 3N grades. We have obtained Mo metal powder with oxygen content of 1450 ppm by hydrogen reduction and subsequent heat treatment for degassing. Using the Mo metal powder, a low-oxygen Mo ingot was prepared by repetitive vacuum arc melting. The oxygen content of the obtained Mo ingot was less than 70 ppm after vacuum arc melting for 30 min. The purity of the Mo metal powder and the ingot was evaluated using glow discharge mass spectrometry. The purity of the respective Mo ingots was increased to 3N and 4N grades from the Mo powder of 2N and 3N grades after the repetitive vacuum arc melting. The low oxygen Mo ingot thus can be used as a raw material for sputtering targets.

• International Journal of Automotive Technology
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• 제6권5호
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• pp.445-451
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• 2005

Most of the pollutants from passenger cars are emitted during the cold-transient phase of the FTP-75 test. In order to reduce the exhaust emissions during the cold-transient period, it is essential to warm up the catalyst as fast as possible after the engine starts, and the Unburned Exhaust Gas Ignition (UEGI) technology was developed through our previous studies to help close-coupled catalytic converters (CCC) reach the light-off temperature within a few seconds after cold-start. The UEGI system operates by igniting the unburned exhaust mixture by glow plugs installed upstream of the catalyst. The flame generates a high amount of heat, and if the heat is concentrated on a specific area of monolith surface, then thermal crack or failure of the monolith could occur. Therefore, it is very important to monitor the temperature distribution in the CCC during the UEGI operation, so the local temperatures in the monolith were measured using thermocouples. Experimental results showed that the temperature of CCC rises faster with the UEGI technology, and the CCC reaches the light-off temperature earlier than the baseline case. Under the conditions tested, the light-off time of the baseline case was 62 seconds, compared with 33 seconds for the UEGI case. The peak temperature is well under the thermal melting condition, and temperature distribution is not so severe as to consider thermal stress. It is noted that the UEGI technology is an effective method to warm up the catalyst with a small amount of thermal stress during the cold start period.

• 한국염색가공학회지
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• 제16권5호
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• pp.28-34
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• 2004

The polarizing film application exploits the unique physicochemical properties between PVA(Poly vinyl alcohol) film and CTA(Cellulose triacetate) film. However, hardly any research was aimed at improving the adhesion characteristics of the CTA film by radio frequency(RF) plasma treatment at argon(Ar) gaseous state. In this report, we deal with surface treatment technology for protective CTA film developed specifically for high adhesion applications. After Ar plasma, surface of the films is analyzed by atomic force microscopy(AFM), roughness parameter and peel strength. Furthermore, the wetting properties of the CTA film were studied by contact angle analysis. Results obtained for CTA films treated with a glow discharge showed that this technique is sensitive to newly created physical functions. The roughness and peel strength value increased with an increase in treatment time for initial treatment, but showed decreasing trend for continuous treatment time. The result of contact angle measurement refer that the hydrophilicity of surface was increased. AFM studies indicated that no considerable change of surface morphology occurred up to 3 minutes of treatment time, but a considerable uneven of surface structure resulted from treating time after 5 minutes.

• 한국식품영양과학회지
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• 제37권11호
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• pp.1529-1533
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• 2008

한약재의 방사선 조사여부를 확인하기 위해 도라지와 오가피에 $0{\sim}10\;kGy$의 감마선을 조사하고 PSL, TL 및 ERS 특성을 비교 검토하였다. PSL을 측정한 결과 비 조사된 한약재에서 한계치($T_1$)인 700보다 낮은 photon count 값을 보이면서 negative로 판정되었고, 0.15 kGy 이상 조사구는 한계치($T_2$)인 5,000보다 높은 photon count 값을 나타내면서 positive로 표시되어 방사선 조사된 것을 확인할 수 있었다. 또한 시료로부터 mineral을 분리하여 TL의 glow curve와 TL ratio($TL_1/TL_2$)를 확인하였다. 방사선 조사가 되지 않은 도라지와 오가피는 TL ratio가 0.007 이하의 값을 나타내었으며, 조사구(1.0 kGy 이상)에서는 0.314 이상의 TL ratio를 나타내었다. 도라지와 오가피는 본 연구에서 설정한 TL ratio의 한계치 0.1보다 높은 수치를 나타내어 방사선 조사여부 확인이 가능하였다. ESR 측정을 통한 방사선 조사 한약재 검지에서는 cellulose 라디칼에서 유래된 특이한 라디칼 신호를 보여주었고, 이는 도라지 시료에서 더욱 뚜렷하게 확인할 수 있었다. 이상의 결과에서 PSL, TL 및 ESR 분석은 도라지와 오가피의 방사선 조사 여부 확인에 적합한 방법임을 확인할 수 있었다

• 한국방사선학회논문지
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• 제8권7호
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• pp.455-459
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• 2014

본 논문에서는 $Li_6Gd(BO_3)_3:Ce^{3+}$ 할라이드 섬광체를 초크랄스키법으로 육성하고, 육성된 단결정의 X선에 대한 섬광 및 열형광 특성에 대하여 조사하였다. $Li_6Gd(BO_3)_3:Ce^{3+}$의 섬광스펙트럼은 $Ce^{3+}$이온의 $4f{\rightarrow}5d$ 천이에 따라 파장범위가 370~500 nm, 피이크 파장은 423 nm 및 455 nm이었다. 섬광감쇠시간 특성은 60 ns의 빠른 시간 특성 성분(25%), 787 ns의 중간 시간특성 성분(29%)과 $5.9{\mu}s$의 느린 성분(46%)의 3개로 구성되며, 잔광에 기여한 포획준위의 물리적 변수를 열형광 측정법에서 분석한 결과, 2개의 포획준위에 기인하며 각 포획 준위의 활성화에너지, 발광차수 및 주파수 인자의 평균값은 각각 0.65 eV, 1.01 및 $6.9{\times}10^8s^{-1}$ 및 0.96 eV, 1.79 및 $3.1{\times}10^{12 }s^{-1}$ 이었다.