http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
고분자물질 및 계면활성제의 유동마찰 저감 특성 비교 연구
하재순(Jae-Sun Ha),유재성(Jae-Sung Ryu),김성수(Seong-Su Kim),조성환(Sung-Hwan Cho),윤석만(Seok-Mann Yoon),엄재식(Jae-Sik Eom) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-
The drag reduction(DR) for Betaine+Amin and Xantan Gum as kinds of surfactant and Polyacrylamide as kinds of polymer solution according to the fluid velocity, temperature and surfactant concentration were compared experimentally. For this study, two kinds of experimental apparatus for short time and long time measurement were established. Each experimental appratus was equipped with hot water storage tanks, pumps, testing pipe network, flowmeter, two pressure gauges and data logging system was built for them. Results showed that Betaine+Amin and Xanthan Gum as kinds of surfactant had appeared optimal DR around 200-500 ppm and their DR tended to be decreased when flow velocity increased but Polyacrylamide as kinds of polymer solution showed the opposite trend to be increased when flow velocity increased. The both of them showed above 40% DR in the case of better condition by the short term measurement. But Polyacrylamide as kinds of polymer solution showed more degradation than Betaine+Amin and Xanthan Gum as kinds of surfactant by the long term measurement. As a result, Betaine+Amin and Xanthan Gum as kinds of surfactant showed better materials to use to the district heating system.
지역난방 공동주택 시스템에서 Smith Predictor 제어기 적용성 연구
정상훈(Sang-Hoon Jung),문연진(Youn-Jin Moon),하재순(Jae-Sun Ha),조성환(Sung-Hwan Cho) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-
It is known that the classical tuning formula for typical PID controllers in general provides unsatisfactory results for industrial plants where the time delay exceeds the dominant lag time. For this reason, alternative strategies have been studied in order to cope with this problem and the most popular scheme is the Smith Predictor(SP). In this paper, the dynamic model of a unit apartment in the district heating system ,which is the control process effected by the dead-time, is developed, and the on/off room temperature control method with the SP simulate using Matlab-Simulink. The simulation results show that the SP works effectively in outdoor temperature variation.
HaCaT 세포주에서 캐모마일 (Matricaria chamomilla) 추출물의 항병원성 및 항염 효과에 관한 연구
임은경(Eun Gyeong Lim),김근태(Guen Tae Kim),김보민(Bo Min Kim),김은지(Eun Ji Kim),김상용(Sang-Yong Kim),한남규(Nam Kyu Han),하재순(Jae Sun Ha),김영민(Young Min Kim) 한국생물공학회 2017 KSBB Journal Vol.32 No.1
Chamomile (Matricaria chamomilla), a member of the Asteraceae family, is a well-known for medicinal plant and can be found in India and Europe. Chamomile is an effective sedative and various medical effects. But, the effects of acne treatment by chamomile were not investigated. Therefore, we assessed the anti-oxidant effects, anti-microbial activity and anti-inflammatory effects by chamomile extracts in HaCaT keratinocyte cells. Anti-oxidant effects of chamomile extracts were investigated by DPPH assay. Also, results of MTT assay was demonstrated that chamomile extracts did not have a cytotoxic effect in HaCaT cells. To assess the antimicrobial activity, we determined formation of inhibition zone of Propionibacterium acnes by extracts from chamomile. Tumor necrosis factor-α (TNF-α) induces production of inflammatory cytokines such as interleukin-1β (IL-1β), IL-6 and IL-8 and expression of COX-2. Chamomile extracts could inhibit TNF-α-induced mRNA expression levels of IL-1β, IL-6, IL-8 and COX-2 gene. These results demonstrated the possibility of chamomile for prevention and treatment of skin inflammatory diseases such as acne.