• 한국항공우주학회지
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• 제39권12호
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• pp.1174-1180
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• 2011

Field Programmble Gate Array(FPGA)는 설계 시간 단축, 재구성 가능성 등의 이유로 우주용 시스템에 사용이 늘고 있다. 그러나, Static Random Access Memory (SRAM) 구조를 가지는 FPGA의 경우 우주 방사능 환경으로 인해 발생하는 single event upset (SEU)로 인한 영향에 더 취약한 단점을 가지고 있다. 과학기술위성 3호 온보드 컴퓨터에서는 SEU로 발생되는 영향을 감소시키기 위하여 triple modular redundancy (TMR)과 Scrubbing scheme (기법)을 사용하고 있다. 실제 방사선 조사 실험 결과, TMR과 Scrubbing 기법을 통하여 문턱 에너지 값이 10.6 MeV에서 20.3 MeV로 개선됨을 확인하였으며, 과학기술위성 3호 위성 궤도 환경을 시뮬레이션 한 결과와 실험 결과를 이용하여 1.23 bit-flips/day의 에러율을 얻었다.

• 대한환경공학회지
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• 제39권9호
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• pp.495-504
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• 2017

도시물순환시스템 내 10 cm 내외로 퇴적된 오염물질과 자갈이나 다양한 구조물에 부착된 부착조류와 협잡물을 쓸어내어(scrubbing) 제거가 가능하며, 오염물질이 주변으로 방출 확산되어 수체의 2차 오염을 방지할 수 있는 덮개(housing)와 혼탁 방지막(turbidity barrier)이 설치된 회전 브러쉬(rotating brush)를 활용한 저혼탁 scrub/흡입(suction)방식의 수륙양용형 퇴적토 준설장치를 개발하였다. 현장적용 검증을 통해, 저수위와 고수위에서 저혼탁 scrub/흡입 준설장치를 이용해 준설 중 수체 내 부유물질(SS)과 탁도(turbidity)의 증가는 매우 미미하며(p>0.05), 일부 부유물질로 인해 발생한 탁도도 준설 후 20분 이내에 빠르게 안정화되는 것으로 조사되었다. 총질소(TN)와 총인(TP)의 농도도 준설 전, 준설 중과 준설 후에 농도 변화가 시간대별 및 수심별로 통계학적으로 유의한 의미는 없는 것으로 조사되어(p>0.05), scrub/흡입 준설을 통해 호수 저면에 축적된 영양염류가 확산되어 수체오염을 유발하지 않는 것으로 조사되었다. 또한, 저혼탁 scrub/흡입 준설장치의 직접 준설을 통한 오염물질 제거량이 수처리시설의 운영을 통한 오염물질 제거량 대비 높은 것으로 산정되어, 수처리시설과 저혼탁 scrub/흡입 준설의 연계 적용이 도시물순환시스템의 수질관리에 효율적인 것으로 평가되었다. 최근에는 GPS 기반 실시간 scrub/흡입 준설장치의 추적 및 유지관리 프로그램을 개발해 등록하고 다양한 도시물순환시스템에 현장 적용하였으며, 추가적으로 준설장치 운전자를 보조 또는 제한된 환경에서 스스로 운전하는 협력형 주행시스템(driver cooperative autonomous driving system)의 개발을 현재 진행 중이다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.337-339
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• 2003

The technology removing radionuclides from soil using soil washing was studied. The main radionuclides contaminated in the soil are Cs$^{137}$ and Co$^{60}$ . It is suitable that scrubbing time is 4 hours and a mixing ratio of soil weight and washing solution volume is 1:10. more than two times continuous scrubbing method with 0.5 M oxalic acid was needed to remove Cs$^{137}$ and Co$^{60}$ from soil more than 70%. Radionuclides removal efficiencies of recycling washing solutions recycled with strong acid resins until 5 times are similar to that of 0.5 M oxalic acid.

• Restorative Dentistry and Endodontics
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• 제17권2호
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• pp.355-364
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• 1992

This is a study on the effect of the dentinal pretreatment method to the bond strength between dentin and glass ionomer cement. In this study, 196 human molar teeth with sound crown were used. The dentin surfaces of these teeth were exposed with wet trimmer and polished with # 800 Emory paper and teeth were divided into 7 groups according to the pretreatment agent and method. Each group has 4 subroups of the kinds of glass ionomers. The shear bond strength were measured by Instron Universal Testing machine model 1122. The data of the evaluations were then subjected to statistical analysis using one way ANOVA and the result were as follows : 1. In Durelon liquid 20 sec scrubbing & Vitrebond filling subgroup, shear bond strength was highest with measurements of 72.41(kg/$cm^2$) and in no pretreatment & Shofu lining cement filling subgroup, lowest with measurements of 4.77(kg/$cm^2$). 2. In no pretreatment group, statistical significant differences were found between the subgroups of G-C lining cement and Shofu lining cement. 3. In Ketac conditioner 20 sec scrubbing group, Vitrebond were bonded stronger than others, and in Ketac conditioner 10 sec passive contact group, it has the significant difference with other glass ionomers except G-C lining cement. 4. The subgroup og G-C dentin conditioner 20 sec scrubbing & G-C lining cement filling was bonded to dentin stronger than the subgroup of no pretreatment & Shofu lining cement. In G-C dentin conditioner groups, both of 10 sec passive contact and 20 sec scrubbing, Vitrebond has highest bond strength among the subgroups. 5. The subgroup of Durelon liquid 10 sec passive contact & G-C lining cement filling was bonded to dentin stronger than the subgroup of no pretreatment & Shofu lining cement. Also in both Durelon liquid groups, Vitrebond were bonded to dentin with the highest strength among the subgroups.

• 한국대기환경학회지
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• 제24권6호
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• pp.674-681
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• 2008

Silver as a metal catalyst has been used to remove odorous compounds. In this study, silver particles in nano sizes ($5{\sim}30nm$) were prepared on the surface of $NaHCO_3$, the supporting material, using a sputtering method. The silver nano-particles were dispersed by dissolving $Ag-NaHCO_3$ into water, and the dispersed silver nano-particles in the aqueous phase was applied to remove inorganic odor compounds, $NH_3$ and ${H_2}O$, in a scrubbing reactor. Since ammonia has high solubility, it was removed from the gas phase even by spraying water in the scrubber. However, the concentration of nitrate (${NO_3}^-$) ion increased only in the silver nano-particle solution, implying that the silver nano-particles oxidized ammonia. Hydrogen sulfide in the gas phase was rapidly removed by the silver nano-particles, and the concentration of sulfate (${SO_4}^{2-}$) ion increased with time due to the oxidation reaction by silver. As a result, the silver nano-particles in the aqueous solution can be successfully applied to remove odorous compounds without adding additional energy sources and producing any harmful byproducts.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.366-367
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• 2006

In general, HF chemistry lifts off the particles during scrubbing after polishing and effectively removes particles. It is sometimes impossible to apply HF chemistry on W plug due to the degradation of electrical characteristics of a device. In this paper, a post W CMP cleaning process is proposed to remove residue particles without applying HF chemistry. After W CMP, recessed plugs are created, therefore they easily trap slurry particles during CMP process. These particles in recessed plug are not easy to remove by brush scrubbing when $NH_4OH$ chemistry is used for the cleaning because the brush surface can not reach the recessed area of plugs. Buffing with oxide slurry was followed by W CMP due to its high selectivity to W. The buffing polishes only oxide slightly which creates higher plug profiles than surrounding oxide. Higher profiles make the brush contact much more effectively and result in a similar particle removal efficiency even in $NH_4OH$ cleaning to that in HF brush scrubbing.

• Nuclear Engineering and Technology
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• 제56권4호
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• pp.1513-1525
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• 2024

An improved mitigation system for thermally-induced steam generator tube rupture accidents was introduced to prevent direct environmental release of fission products bypassing the containment in the OPR1000. This involves injecting bypassed steam into the containment, cooling, and decontaminating it using a water coolant tank. To evaluate its performance, a severe accident analysis was performed using the MELCOR 2.2 code for OPR1000. Simulation results show that the proposed system sufficiently prevented the release of radioactive nuclides (RNs) into the environment via containment injection. The pool scrubbing system effectively decontaminated the injected RN and consequently reduced the aerosol mass in the containment atmosphere. However, the decay heat of the collected RNs causes re-vaporization. To restrict the re-vaporization, an external water source was considered, where the decontamination performance was significantly improved, and the RNs were effectively isolated. However, due to the continuous evaporation of the feed water caused by decay heat, a substantial amount of steam is released into the containment. Despite the slight pressurization inside the containment by the injected and evaporated steam, the steam decreased the hydrogen mole fraction, thereby reducing the possibility of ignition.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2004년도 추계학술대회 논문집
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• pp.457-458
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• 2004

• 한국분무공학회지
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• 제18권2호
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• pp.81-86
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• 2013

To comply with the regulation of the reinforcing Clean Air Conservation Act, it is necessary for the semiconductor manufacturers to develop effective low-concentration acid gas abatement system to treat the flue gas. The low-concentration acid gas was found to be harder to deal with than the high-concentration one. In this study, the effect of various potential treatments such as air-assist nozzle spraying, magnetizing the scrubbing water, and adding surfactants to spraying and scrubbing water were investigate through the application of the statistical ANCOVA method, which was proved to be very useful tool when the inlet concentration of acid gas could not be controlled precisely and it affected the removal efficiency of the abatement system.

• 한국안전학회지
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• 제12권2호
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• pp.102-111
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• 1997

An In-line dry scrubbing FGD process was investigated. Calcium hydroxide was entrained in flue gas and the SO$_2$ removal efficiency by humidity and additives were examined. The range of reaction temperature was $200^{\circ}C$~$500^{\circ}C$ and the concentration of $SO_2$ was around 900ppm. By the increase of humidity in flue gas, the removal efficiency was increased. The effect of NaOH as a additive was very high and got high conversion of $Ca(OH)_2$, however in case of RH 90%, it was reverse. The effect of particle size and flow rate were examined. And the reaction rate constant and effective diffusivity also calculated.