• Journal of the Korean Chemical Society
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• v.34 no.3
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• pp.255-259
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• 1990

The nitrogen-laser flash photolysis apparatus has been set up to detect directly the transient produced from the excited Benoxaprofen (BXP). The function of the instrument has been tested by using anthracene as a standard sample. The laser photoexcitation of BXP in ethanol has been carried out under a constant stream of $N_2$ gas and a transient absorption spectrurn has been recorded over the 400-600 nm. The effects of oxygen and ${\beta}-carotene$ on the transient spectrum reveal that thee maximum transient absorption at 415 nm is attributed to the triplet state of BXP and the triplet energy of BXP is above 22 Kcal/mole. In addition to the triplet state, another transient species has been observed to be produced, which is probably a radical form of BXP. The photosensitization mechanism of BXP is discussed based on these results.

• Journal of Korean Electronics
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• v.24 no.1
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• pp.42-46
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• 2004

• Journal of Korean Electronics
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• v.24 no.10
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• pp.56-57
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• 2004

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.150-151
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• 2001

• Journal of the Microelectronics and Packaging Society
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• v.24 no.3
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• pp.47-52
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• 2017

This research scrutinizes the data retention characteristics of the MLC NAND Flash Memory instigated by the loss effect of trapped charge when the memory is in the state of program saturation. It is attributed to the threshold voltage saturation phenomenon which engenders an interruption to the linear increase of the voltage in the memory cell. This phenomenon is occasioned by the outflow of the trapped charge from the floating gate to the control gate, which has been programmed by the ISPP (Incremental Step Pulse Programming), via Inter-Poly Dielectric (IPD). This study stipulates the significant degradation of thermal retention characteristics of threshold voltage in the saturation region in contrast to the ones in the linear region. Thus the current study evaluates the data retention characteristics of voltage after the program with a repeated reading test in various measurement conditions. The loss effect of trapped charge is found in the IPD layer located between the floating gate and the control gate especially in the nitride layer of the IPD. After the thermal stress, the trapped charge is de-trapped and displays the impediment of the characteristic of reliability. To increase the threshold saturation voltage in the NAND Flash Memory, the storage ability of the charge in the floating gate must be enhanced with a well-thought-out designing of the module in the IPD layer.

• Fire Science and Engineering
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• v.12 no.2
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• pp.3-15
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• 1998

The consequence analysis for jet and flash fire accidents by the continuous release of butane vapor was performed and effects of process variables on consequences were analyzed in standard conditions. For the continuous release (87.8 kg/s) of butane vapor at 8m elevated height in the debutanizing process of the naphtha cracking plant operating at 877 kPa, 346.75 K, we found that for the jet fire accident, shape and size of the flame could be predicted and thermal radiation estimated by API model at 200m distance from release point was 1.5kW/$m^2$, and that for the flash fire accident, effect range was 11.2~120.2m. Also, simulation results showed that effects of operating pressures on consequences were larger than those of operating temperatures and results of accidents were increased with increasing operating pressures. At this time, effects of operating pressures on XUFL were smaller(about 1/10) than those on XLFL for the flash fire accident.

• Fire Science and Engineering
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• v.17 no.4
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• pp.117-123
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• 2003

In this study; the ignition and heat release rate characteristics of rigid polyurethane foam were investigated in accordance with setchkin ignition tester and cone calorimeter which is using oxygen consumption principle. In the ignition temperature study; flash-ignition temperature was $383^{\circ}C$-$390^{\circ}C$, self-ignition temperature was$ 493^{\circ}C$∼495$^{\circ}C$. The self-ignition temperature of rigid polyurethane foam was about $100^{\circ}C$ higher than the flash-ignition temperature. In the cone calorimeter study, the time to ignition of rigid polyurethane foam was faster as the external heat flux increase. In the same heat flux level, the time to ignition was faster as the density of rigid polyurethane foam decrease. Also the heat release rate was the largest value at the heat flux of /$50 ㎾\m^2$ and had a tendency of increase as the heat flux level and density increase. In the standpoint of time to ignition and heat release rate, the fire performance of rigid polyurethane foam was influenced by the applied heat flux level and density and the flashover propensity classified by Petrella's proposal was high.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.105-118
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• 2021

The purpose of this study is to explore the American Youth Film Director Damien Chazelle and his cinema world. Chazelle as a youth director directs three movies as (2014), (2016), (2018) in Hollywood, and represents youth directors in Hollywood. For this study, adopt two research methodologies which are 'Auteurism' and 'culture studies', and explore traits of esthetics, subject and context meaning by analyzing representative three movies. Lastly examines significance of his movies in Hollywood history. This study concludes that Chazelle is a 'Auteurism director of self-reflexivity' who has three things in common as 'narrative: success myth', 'mise-en-scene: Chazelle's world', 'self-reflexivity: Auteurism film directing'. Youth film director Chazelle is opening up the future of Hollywood as a 'Auteurism film of self-reflexivity' and the creative film directing of the youth generation.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.1018-1021
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• 2009

여기시켜 고출력, 고안정화 레이저 빔 특성을 실험적으로 분석 및 고찰하였다. 실험적 결과 완전한 형태의 선형적인 레이저 빔 특성을 얻을 수는 없었으나 레이저 특성인 거의 선형적인 모양의 그래프 특성이 나타남을 확인할 수 있었다.

• Proceedings of the KAIS Fall Conference
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• 2012.05b
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• pp.762-764
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• 2012

본 연구에서는 잉곳을 절삭하여 웨이퍼를 만들 때 발생하는 슬러리로부터 SiC를 분리하고, 이를 재생시켜 다공성 SiC 세라믹 히트싱크를 제작하였다. 또한 제작 된 다공성 SiC 세라믹 히트싱크의 열적물성치를 레이저 플래쉬 방법으로 측정하였고 알루미늄 히트싱크와의 비교실험을 통해 다공성 SiC 세라믹 히트싱크의 방열성능을 검증하였다.