• 한국지반환경공학회 논문집
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• 제5권1호
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• pp.27-34
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• 2004

매립이 완료된 소규모 매립지의 쓰레기층에 대하여 JSP 공법으로 지반안정화 후 재이용시 응용자료로 제공하기 위하여 공법전과 후의 매립가스 변화를 알아보았다. 부지 내에 매립된 쓰레기로부터 발생되는 매립가스를 안정화전과 안정화 직후 및 28개월이 경과한 후에 대하여 측정하여 비교 분석 하였다. 이 결과 매립가스 중 $H_2S$와 $NH_3$는 각각 안정화전 123.51ppm과 171.54ppm로 TWA값을 초과하여 문제가 되었으나 안정화 직후 각각 55.59ppm, 20.51ppm으로 낮아진 후 다시 시간경과에 따라 9.04ppm과 11.82ppm으로 낮아졌고, 매립지에서의 주요 발생가스인 메탄과 그 외 다른 매립가스를 측정한 결과 안정화 후 극히 미량 검출되었거나 검출되지 않아 안정화전 문제가 되었던 가스의 발생이 지반안정화를 통하여 줄어들었다.

• 한국전기전자재료학회논문지
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• 제36권2호
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• pp.99-108
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• 2023

Currently, semiconductor manufacturing industry heavily relies on a wide range of high global warming potential (GWP) gases, particularly during etching and cleaning processes, and their use and relevant carbon emissions are subject to global rules and regulations for achieving carbon neutrality by 2050. To replace high GWP gases in near future, dry etching using alternative low GWP gases is thus being under intense investigations. In this review, we report a current status and recent progress of the relevant research activities on dry etching processes using a low GWP gas. First, we review the concept of GWP itself and then introduce the difference between high and low GWP gases. Although most of the studies have concentrated on potentially replaceable additive gases such as C₄F₈, an ultimate solution with a lower GWP for main etching gases including CF₄ should be developed; therefore, we provide our own perspective in this regard. Finally, we summarize the advanced dry etch process research with low GWP gases and list up several issues to be considered in future research.

• 한국결정성장학회지
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• 제14권5호
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• pp.220-225
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• 2004

Four different Fluorine-based gases ($SF_6/,NF_3, PF_5,\; and \; BF_3$) were examined for high rate Inductively Coupled Plasma etching of Si. Etch rates up to ~8$\mu\textrm{m}$/min were achieved with pure $SF_6$ discharges at high source power (1500 W) and pressure (35 mTorr). A direct comparison of the four feedstock gases under the same plasma conditions showed the Si etch rate to increase in the order $BF_3$ < $NF_3$< $PF_5$ < $SF_6$. This is in good correlation with the average bond energies of the gases, except for $NF_3$, which is the least strongly bound. Optical emission spectroscopy showed that the ICP source efficiently dissociated $NF_3$, but the etched Si surface morphologies were significantly worse with this gas than with the other 3 gases.

• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3527-3531
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• 2014

In this paper, we report thermodynamic and transport properties (diffusion coefficient, viscosity, and thermal conductivity) of diatomic gases ($H_2$, $N_2$, $O_2$, and $Cl_2$) at 273.15 K and 1.00 atm by performing molecular dynamics simulations using Lennard-Jones intermolecular potential and modified Green-Kubo formulas. The results of self-diffusion coefficients of diatomic gases obtained from velocity auto-correlation functions by Green-Kubo relation are in good agreement with those obtained from mean square displacements by Einstein relation. While the results for viscosities of diatomic gases obtained from stress auto-correlation functions underestimate the experimental results, those for thermal conductivities obtained from heat flux auto-correlation functions overestimate the experimental data except $H_2$.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1533-1539
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• 2007

It is mainly due to the toxic gases, produced from the material combustion, threatens human body in case of urban railway car like subway which passes through underground tunnel. In the field of railway industry, fire accidents was not frequent but occurs in each country and, the causes was investigated. The advanced country established the test standard (e.g., BS, EN) to measure the toxic gases quantitatively and, have applied to enhance the fire safety of railway car. We must also follow the procedures to use gangway material for railway car as stated the Safety regulation for the urban railway car. In this study, various gangway materials(silicon, synthtic rubber, soaltapulin) are used to investigate element of toxic gases when the fire occurs. The amount of toxic gases measured from the ISO 5659 chamber using cone heater was measured and compared the results for each materials.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2003년도 춘계 학술발표회 논문집
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• pp.359-364
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• 2003

Heat regenerator occupied by regenerative materials improves thermal efficiency of regenerative combustion system through the recovery of sensible heat of exhaust gases. By using one-dimensional two-phase fluid dynamics model, the unsteady thermal flow of regenerator with spherical particles, were numerically analyzed to evaluate the heat transfer and pressure losses and to suggest the parameter for designing heat regenerator. It is confirmed that the computational results, such as air preheat temperature, exhausted gases outlet temperature, and pressure losses, agreed well with the experimental data conducted from Chugairo. The thermal flow in heat regenerator varies with porosity, configuration of regenerator and diameter of regenerative particle. Assuming a given exhaust gases temperature at the regenerator outlet, the regenerator length need to be linearly increased with inlet Reynolds number of exhaust gases. It is considered that inlet Reynolds number of exhaust gases should be introduced as a regenerator design parameter.

• Carbon letters
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• 제1권1호
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• pp.31-35
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• 2000

[ $SO_2$ ]and NO gases that come from the flue gases of most of all industrial combustion processes are harmful to everything include person and industrial facilities. For the simplification of the environmental clean-up processes, we studied the decomposition process by microwave. The microwave can destroy molecules into elementary atoms and offers energy to the atoms to react with carbons. Since the microwave is not absorbed into quartz tube and metallic chamber, the air pollution gases can be removed with much lower energy than in the case of conventional methods. We studied the decomposition of $SO_2$ and NO gases on the carbon beds by microwave. In the microwave field, the gases can be decomposed to form other compounds, such as elementary sulfur, nitrogen, carbon monoxide and carbon dioxide. It was found that CO gas is formed at higher temperature than is $CO_2$ gas, so it needs to control the bed temperature depend on products that we want to get.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2011년도 추계학술대회
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• pp.55-66
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• 2011

Recently developed a variety of architectural interior decoration according hwadoeme type of toxic gases generated during fire also are becoming diversified, resulting in fatal casualties occurred in the trend is also being increased. During a fire, toxic gas that is generated varies depending on the combustible material occurs. However, all combustible materials, including carbon, incomplete combustion of carbon monoxide which is generated in the most common toxic gases can be seen as one. Accordingly, in this study of organic solids that are generated in case of fire toxic gases, and briefly discuss the characteristics of the risks and, by far the most common Co gas for measures to prevent human casualties, seolbijeok, the temperature dependence, divided into four aspects of administrative daechaekdeung explained.

• 한국안전학회지
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• 제6권1호
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• pp.26-30
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• 1991

Flammability, and released toxic halogen gases during combustion about two kinds of flame-retardant flexible foam(F.R. flexible PV foam) were investigated. One of the above was F.R. flexible PU foam with the containment of halogen and the other was manufactured with pure flexible PU foam in aqueous solution of alumina trihydrate(ATH) and dried 4 hours at 10$0^{\circ}C$. Flammability by L.O.I and UL94 HF-1 of the two materials were similarly shown. And combustion gases were analyzed with GC-Mass. HCI, CI$_2$ and HF were detected at both halogen being contained F.R. flexible PU foam and ATH dolng one The reason, to find halogen gases from burning ATH-containing F, R. flexible PU foam which wasn't used for any halogenated F.R., could be considered as by using trichlorofluoromethane with blowing agent to make PU foam. The relative quanity of relesed halogen gases of F.R. flexible PU foam with the containment of halogen had been indicated tree times HCI and CI$_2$, two times HF than ATH containing, respectively.

• 센서학회지
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• 제24권5호
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• pp.311-318
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• 2015

The excess use and generation of various toxic gases from many industrial complexes and plant facilities have increased the possibility of leakage or explosion accidents, which can cause fatal damage to human beings in the wide range of neighboring area. To prevent the exposure to the fatal toxic gases, it is very important to monitor the leakage of toxic gases using gas sensors in real time. Various types of gas sensors, which can be classified as semiconductor, electrochemical, optical, and catalytic combustion types according to the operating principles, have been developed. In this review, the operation principles of gas sensors are explained and the performance of those sensors is compared. The state-of-the-art gas sensor technologies developed by research institutes or companies are reviewed also.