• 분석과학
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• 제13권4호
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• pp.412-422
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• 2000

실리콘 웨퍼 산업계의 청정실에서 사용되는 에어샤워기중 고분자로 제작된 부품들을 $100^{\circ}C$에서 30분간 다이나믹 해드 스페이스에서 가스로 용출한 후 GC-MS로 분석 하였다. 에어샤워기가 가동중인 청정실의 대기를 흡착관 튜브방식으로 채취하였고, 이러한 흡착관 튜브에 흡착된 유기화합물은 쏙시렛 용출법을 이용하여 용출한 후 GC-MS로 분석하였다. 에어샤워기의 제조 부품(electric over current relay, acryl plate. polycarbonate window, filter, fan housing, steel galvanized cold plate and canvas buffer)들로 부터의 분석결과 대부분의 성분들은 제조부품의 고분자 성분들에서 유래되었음을 확인 할 수 있었으며, 에어샤워기가 가동중인 청정실의 대기분석 결과와 비교 분석되었다. 이러한 분석결과의 비교 연구는 청정실내에서의 유기오염물질이 에어샤워기의 고분자 제조부품으로부터 유래 되었는지를 확인하게 해준다.

• 천문학회보
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• 제36권1호
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• pp.70.2-70.2
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• 2011

Ultra-high energy cosmic rays(UHECRs) refer cosmic rays with energy above 1018eV. UHECR experiments have employed air shower simulations to quantify the properties of cosmic rays. Using COSMOS and CORSIKA, we have produced a library of over 15000 thinned extensive air shower(EAS) simulations with the primary energies ranging from 1018.5eV to 1020eV and the zenith angle of primary cosmic ray particles from 0 to 45 for proton and iron primaries. We have compared the results from CORSIKA and COSMOS. The comparison has shown perceptible differences in the ground distributions, longitudinal distributions, Calorimetric energy, and Xmax distributions. We have also measured the detector response evaluated using GEANT4 simulations. Here, we discuss S(800), i.e. the signal at a distance of 800 m from the shower core, as the primary energy estimator and present the lateral distribution function(LDF) with S(800).

• 토지주택연구
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• 제12권2호
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• pp.91-97
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• 2021

본 연구는 에어샤워 시스템의 가동에 따른 5종의 의류(Dress Suit, Hiking Clothes, Knit, Cotton T-Shirt, Coat)의 미세먼지의 제거성능을 파악하고자 한 것으로 그 연구결과를 요약하면 다음과 같다. 첫째, 에어샤워 시스템 가동 실험결과, 미세먼지 제거율은 1회 가동시에만 평균 59.4%가 제거 되고 있었다. 특히, 2회 및 3회 가동시에는 68.5%에서 최고 73.3% 까지 제거율을 나타내고 있었다. 둘째, 5종류의 의류종류별 제거율은 Dress Suit 74.0% > Hiking Clothes 70.6% > Knit 63.3% > Cotton T-Shirt 50.5% > Coat 38.8% 순으로 나타났다. 즉, 의류 종류에 따라 코트 등 털 소재의 의류는 정전기 등의 원인으로 미세먼지 제거율이 다른 소재에 비해 적게 나타났지만 보통 의류인 경우는 50% 이상의 제거율을 보이고 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.585-589
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• 2008

This study is performed to analyze the fluid flow about 150mm shower heads of semiconductor device. Under the air pressure, the ideal gas of moving fluid is injected as 5m/s velocity into inlet of shower heads and the flow distribution in shower heads is measured according to pitch of plasma distribution device. As results, the maximum and minimum value of fluid velocity are investigated with their position. The velocity values at outlet are also studied. From two experiment using the plasma distribution device, the results of CFD are compared with the experimental results. That results shows stable flow of fluid in that case of corrected design from CFD.

• 한국환경과학회지
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• 제1권1호
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• pp.47-51
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• 1992

수중에 존재하는 휘발성 유기화합물은 샤워를 하는동안 공기로 방출되고 공기농도는 샤워 변수에 따라 달라지는데, 이는 휘발성 유기화합물의 호기농도의 변화를 야기 시킨다. 본 연구에서는 샤워를 하는 동안 공기중의 클로로포픔 노출에 영향을 미치는 주요한 샤워변수(물온다 및 노출시간)를 클로로포픔 호기농도를 측정하여 검토 하였다. 크롤로포름 호기농도는 물의 온도와 노출 시간이 증가함에 따라 증가 하였다. 가장 큰 클로로포름 호기농도 차이를 나타내는 두개의 흡기 노출 조건은 미지근한 물을 이용한 5분 동안의 노출과 더운 물을 이용한 15분 동안의 노출이었다. 클로로포름 호기농도는 후자의 노출후에 전자의 경우보다 거의 3배 정도 높았다. 주요 샤워변수와 수중농도로 조정된 호기농도 사이의 수학모델은 0.0001의 확률에서의 데이타와 훌륭한 일치되는 결과를 나타내었다.

• 천문학회보
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• 제35권2호
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• pp.57.2-57.2
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• 2010

Cosmic rays with energy exceeding 10^18eV are referred to as Ultra high energy cosmic rays (UHECRs). UHECR experiments have utilized air shower simulations to estimate the properties of cosmic rays. Telescope array (TA) experiment has used COSMOS and CORSIKA mainly; the Monte Carlo codes of CORSIKA and COSMOS simulate the evolution of extensive air showers in the atmosphere initiated by photons, hadrons or nuclei UHECRs. We compare the simulations from CORSIKA and COSMOS. Comparison has shown noticeable differences at the ground distributions, longitudinal distributions, Calorimetric energy, and Xmax value. The implications of our results are discussed.

• 천문학회보
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• 제36권2호
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• pp.128.2-128.2
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• 2011

Experiments to study high-energy cosmic rays (CRs) employ Monte Carlo codes for extensive air shower (EAS) simulations to figure out the properties of CRs. COSMOS and CORSIKA among EAS simulation codes are currently being used to analyze the data of the Telescope Array experiment. We have generated a library of about 10,000 simulated EASs with the primary energy ranging from $10^{18.5}eV$ to $10^{20}eV$ and the zenith angle of primary particles ranging from 0 to 45 degree for proton and iron primaries. We have compared the results predicted by CORSIKA and COSMOS under the same condition. In this talk, we show the differences in the energy spectra at the ground, the longitudinal shower profile as a function of atmospheric depth, the Calorimetric energy, and the Xmax distribution. We also discuss the lateral distribution function obtained from GEANT4 simulations which is being used to measure the detector response.

• 천문학회보
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• 제37권1호
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• pp.69.1-69.1
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• 2012

Monte Carlo codes for extensive air shower (EAS) simulate the development of EASs initiated in the Earth's atmosphere by ultra-high energy cosmic rays (UHECRs) with energy exceeding - $10^{18}$ eV. Here, we compare EAS simulations with two different codes, CORSIKA and COSMOS, presenting quantities including the longitudinal distribution of particles, depth of shower maximum, kinetic energy distribution of particle at the ground, and calorimetric energy. In addition, the lateral distribution of local energy density far from the EAS core has been known as an important quantity to estimate the energy of UHECRs. We also present the lateral distribution function obtained from GEANT4 simulations for detector response.

• 설비공학논문집
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• 제16권2호
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• pp.128-134
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• 2004

In order to verify and take measures against a variety of troubles which cannot be predicted in a well-controlled laboratory, it is necessary that solar system should be experimented in an actual situation during a long period. Through this experiment it can be also understood how the load pattern and operational conditions expected in a design process become different to those in the actual running, which can be applied to a new system design. We installed 6 kW solar hot water heating system with a shower facility and operated during 7 months. As a result, average 8.3 persons took a shower a day； solar fraction is 71％ and total collector efficiency is 40％ during the periods from March to September. We confirmed several troubles encountered in the actual situation and considered practical center-measures.

• 한국염색가공학회지
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• 제12권3호
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• pp.207-217
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• 2000

A new, high-efficiency ultrasonic fabric washing machine was developed to be an energy-efficient washing machine and to enhance fabric washing quality in washing processes of the dyeing and finishing process in the textile industry. This system is composed of ultrasonic wave generator, air blowing nozzle, torque motor for fabric tension control, and enclosed washing bath, multi-tube type exchanger, noiseless heater, air cylinder, expander roller, mangle upper and lower rollers, bend bar, dancer, shower spray nozzle, and solenoid valve, and so on. These elements are synergised for fabric washing. One of the very important principles is the low tension fabric running system. For an efficient washing effect, a counter flow system is also adopted. The new system also adopts the dancer and torque motor to control fabric tension and prevent fabric creasing. Shower spray nozzle, counter flow and overflow apparatus, and air-blowing apparatus are adopted to enhance the fabric washing effect. In this study, peach yoryu, exter, and moss crepe fabrics were washed by the general and ultrasonic washing systems under different conditions respectively. The washing efficiency was affected by the fabric running speed and characteristics of fabrics. Size content after washing increased with increasing the fabric running speed. The values in the general washing system were higher than those of the ultrasonic washing system. The changes of conductivity in the ultrasonic and the cooling bath were affected by the running time under the ultrasonic generating. The values of conductivity decreased as the experimental time passed.