CFD를 이용한 자동차 사이드 미러의 공력특성 연구

민선식,한준규,권기현,최은동,김문상,Min, Sun-sik,Han, Jun-Kyu,Kwon, Ki Hyun,Choi, Eun-Dong,Kim, Moon-Sang 항공우주시스템공학회 2008 항공우주시스템공학회지 Vol.2 No.2

Aerodynamic characteristics, such as drag and lift, play an important role in automobile design under certain speed conditions. Such characteristics are essential to design an automobile since they are directly related to automobile's performance such as passenger safety and fuel consumption. There is a huge demand for the automobile to have safe performance at high speed. Reduction in drag is also important and it could lead to the solution of air flow induced noise and dust problems. The objective of this research is to find out the aerodynamic differences between conventional side mirror and a modified one using CFD. Although drag generated around a side mirror is only about 7% of the total drag when a car runs, it is very closely related to driver's field of vision and noise generation. CFD simulation of the flowfield around a car side-view mirror was performed using a commercial code; Gambit and FLUENT.

백서에서 바질 에센셜 오일의 항통각 효과

민선식 ( Sun Seek Min ),한승호 ( Seung Ho Han ),이재용 ( Jae Yong Yee ),김찬 ( Chan Kim ),설근희 ( Geun Hee Seol ),임재형 ( Jae Hyeung Im ),김형태 ( Hyung Tae Kim ),이규창 ( Kyu Chang Lee ),김혜영 ( Hye Young Kim ),이명종 ( Myeon 대한통증학회 2009 The Korean Journal of Pain Vol.22 No.3

Japanese Export Price Strategy during the Appreciation of the Yen

민선식 ( Sun Shik Min ) 한국국제경영학회 1992 國際經營硏究 Vol.3 No.1

This paper examines how Japanese exporters were able to retain their market shares in Korea when the yen appreciated sharply beginning from 1985. The limited decrease in Japan`s share resulted from (1) an opportunistic share-holding pricing strategy of Japanese exporters: they reduced yen prices even further to retain their shares in cases where they were otherwise likely to lose large shares, and (2) inelastic Korean demand. This study focuses on the pricing behavior of Japanese exporters, using Korean import data and information from field interviews. Some factors enabled Japanese exporters to reduce yen prices. Yen costs of imported inputs for Japan`s exports fell, and Japanese exporters squeezed profit margins that existed before the yen appreciated. Some of them even subsidized price reductions with part of the windfall profits that they realized at home because they did not pass on the decrease in cost of imported inputs to domestic consumers. Subsidized price reductions, accompanied by cost reduction efforts, were a long-term strategy of preempting the entry of competitors since cost reduction required time. If the yen appreciates further, Japanese exporters are likely to substitute imported inputs for Japanese domestic value-added or shift to foreign production while reducing yen prices to defend their markets. This paper uses data from the author`s doctoral dissertation at the Harvard Business School, “The Appreciation of the Yen and Japan`s Exports to Korea.”The author received valuable comments from Louis T. Wells, Jr., Alice H. Amsden, and Benjamin-Gomes Casseres, and financial support from the Harvard Business School`s Division of Research for the dissertation.

갈화 ( Puerariae flos ) 추출물이 Rat 혈중 Ethanol 농도에 미치는 영향

김정한(Jeong Han Kim),민선식(Sun Sik Min),김성훈(Sung Hoon Kim),홍희도(Heu Do Hong),김종수(Jong Soo Kim),김수언(Soo Un Kim) 한국응용생명화학회 1995 Applied Biological Chemistry (Appl Biol Chem) Vol.38 No.6

Ethanol concentration in blood, brain and liver of rats was shown to be effectively lowered by arrowroot flower extract. The lowering effect for ethanol concentration in blood was maximum when measured after 1 hour from ethanol feeding. Hot water extract was more effective than 80% ethanol extract. The treatment of extract at 10 min. before ethanol feeding gave a better result than that at 10 min after or 1 hour before ethanol feeding. The ethanol concentration in brain and liver was lowered as found in the blood ethanol concentration. Acetaldehyde was not detected either in blood or the tissues. The optimal amount of the Puerariae flos was 55.7㎎/㎏·body weight. The newly developed analytical method using dichloromethane as extracting solvent was proven to be very effective in terms of speed and simplicity.

바질 에센셜 오일 향흡입이 척추수술 전 만성요통환자에서 통증, 불안 및 활력징후에 미치는 효과

강푸름(Purum Kang),정금미(Kum Mi Jung),민선식(Sun Seek Min),설근희(Geun Hee Seol) 대한스트레스학회 2012 스트레스硏究 Vol.20 No.3

Ocimum basilicum L.은 민간요법에서 통증, 염증 및 고혈압을 치료하는데 사용되어 온 식물로 알려져 있다. Ocimum basilicum L.에서 추출된 바질 에센셜 오일을 사용하여 만성 요통으로 척추수술을 받기 위해 입원 중인 환자를 모집단으로 하여 농도에 따른 바질 에센셜 오일 향흡입이 척추수술 전 통증, 불안 및 활력징후에 미치는 효과를 규명하기위해 이중맹검법을 이용한 무작위 대조군 전?후 실험설계로 검증한 연구이다. 연구대상자는 0.1%, 1%, 5%의 바질에센셜 향흡입군 및 대조군으로 무작위 배치되었으며 통증, 불안, 기분상태(profile of mood states), 수축기 혈압, 이완기 혈압, 맥박 및 호흡수를 바질 에센셜 오일 향흡입 전·후에 측정하였다. 연구결과 0.1%와 1%의 바질 에센셜 오일을 흡입한 군은 대조군에 비해 유의미한 통증의 감소를 나타내었으며(p=.022, p=.022, respectively) 5%의 바질 에센셜 오일을 향흡입한 군에서는 대조군에 비해 이완기 혈압을 유의미하게 감소시켰다(p=.023). 반면에 수축기 혈압 및 맥박, 호흡수, 기분상태 및 불안은 대조군에 비해 실험군에서 감소하는 경향은 보였으나 네 그룹 간 유의미한 차이를 나타내지 않았다. 따라서, 본 연구 결과로 미뤄볼 때 바질 에센셜 오일 향흡입은 농도 비의존적으로 특정 농도에서 통증 완화 및 이완기 혈압을 조절시키는 효과가 있음을 알 수 있었으며 이러한 연구결과는 향후 임상에서 아로마요법 시행 시 아로마 에센셜 오일의 적정 농도 선별이 선행되어야함을 시사하고 있다. Ocimum basilicum L. (basil essential oil, BEO) is a plant used in traditional folk medicine for the treatment of pain, inflammation and hypertension. BEO-inhalation was used to examine the effects of the odor of BEO and BEO concentration dependency on pain and anxiety before spine surgery in patients with chronic low back pain. A total of sixty patients were randomly assigned to one of the four study groups (control, 0.1%, 1%, 5% BEO-inhalation group). Pain-visual analog scale (P-VAS), anxiety-visual analog scale (A-VAS), profile of mood states (POMS) test, blood pressure, heart rate, and respiratory rate were measured before and after inhalation of the odors for five minutes. Inhalation of BEO at 0.1%, 1% concentration caused significant decreases in P-VAS compared with control (p=.022, p=.022, respectively), meanwhile 5% BEO-inhalation significantly reduced in diastolic blood pressure compared with control (p=.023). However, there was no significant difference among the four groups in systolic blood pressure, heart rate, respiratory rate, A-VAS, POMS test. In patients with chronic low back pain before spine surgery, 0.1% and 1% BEO-inhalation is effective in alleviating pain and 5% BEO-inhalation reduce diastolic blood pressure. In conclusion, BEO-inhalation at specific concentrations can be useful method for the relief of pain and blood pressure control for patients with chronic low back pain before spine surgery. (Korean J Str Res 2012;20:169∼178)

클라리세이지 향흡입이 치주염환자의 치료 시 통증 및 스트레스에 미치는 효과

유지혜 ( Ji Hye You ),김미영 ( Mi Young Kim ),문혜경 ( Hae Kyung Moon ),민선식 ( Sun Seek Min ),설근희 ( Geun Hee Seol ) 대한예방치과·구강보건학회 2011 大韓口腔保健學會誌 Vol.35 No.1

Objectives. The purpose of this study was to investigate the analgesic and antistress effect of clary sage-inhalation in periodontitis patients. Methods. Thirty-five patients with periodontitis, who were classified under Russell`s Periodontal Index, were studied from September to December 2009. All patients understood the purpose of this study and written informed consent for the study was obtained. Results. Clary sage-inhalation was conducted during the treatment period. Blood pressure, pulse, visual analog scale, and salivary cortisol levels were measured before and after treatment. The visual analog scale score which represents subjective pain perception in the experimental (clary sage-inhalation) group was significantly lower than that in the vehicle (almond oil-inhalation) or control (saline-inhalation) group. In addition, the experimental group showed the lowest systolic and diastolic blood pressure and pulse rate among the three groups. However, there was no significant difference in salivary cortisol level among the three groups. Conclusions. Clary sage-inhalation is effective in alleviating pain and blood pressure. These results suggest that clary sage-inhalation can be a useful method for the relief of pain during the treatment of periodontitis.

백서의 슬관절강내 주입된 Agmatine과 Clonidine이 슬관절통의 유도 및 유지에 미치는 효과

이명종 ( Myeong Jong Lee ),심현수 ( Hyen Soo Shim ),설근희 ( Geun Hee Seol ),김필주 ( Pill Joo Kim ),한승호 ( Seung Ho Han ),이재용 ( Jae Yong Yee ),김찬 ( Chan Kim ),이규창 ( Kyu Chang Lee ),김혜영 ( Hye Young Kim ),민선식 ( Sun 대한마취과학회 2008 Korean Journal of Anesthesiology Vol.54 No.6

고양이 방광의 기계적 수용체에 대한 노르에피네프린의 억제 효과

오현주,홍승길,민선식,이서은,황종문,강유진,한희철,윤영욱 대한마취과학회 2001 Korean Journal of Anesthesiology Vol.40 No.3

Background: Recent findings suggest that a coupling between the somatic and sympathetic nervous system is critical not only for the development but also for the maintenance of pain behavioral changes. However, studies on the effect of sympathetic efferent system on sensory receptors in the visceral organ that is more dependent on the autonomic nervous system are lacking. This study examined whether norepinephrine (NE) had an influence on the mechanoreceptors in the feline urinary bladder. Methods: Ten adult male cats were used and anesthetized with α-chloralose and artificially ventilated. A cannula with the pressure transducer was inserted through the urethra to apply mechanical stimuli and monitor the pressure of bladder. A tiny caulula inserted into the bilateral side branches of vesical arteries were used as a route for a NE (10 ㎍ bilaterally) injection. Nerve fiber recordings were obtained from the distal stump of the pelvic nerve. Results: After the NE injection, the response of mechanoreceptors (n = 13) to the isotonic pressure stimulus (50-60 mmHg) decreased significantly (p < 0.05) in terms of sensitivity (i.e., ratio of nerve activity change to urinary bladder pressure change). The responses to pressure stimuli after an injection of an α 1 adrenoceptor blocker (terazosin) reversed the effect of NE. The responses of mechanoreceptors to isotonic pessure stimulus were not affected significantly by NE with preinjection of an α2 adrenoceptor blocker (yohimbine). Conclusions: These results suggest that NE may have influence on the sensitivity of mechanoreceptois in the normal feline urinary bladder via an α1 adrenoceptor. (Korean J Anesthesiol 2001; 40: 406~412)