• 대한한방내과학회지
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• 제28권3호
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• pp.502-509
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• 2007

Objectives : Folium perillae (FP) can relieve superficial pathogenic factors to dissipate cold and promote the circulation of qi and regulate the function of the stomach and is often used for interior qi-stagnation. We hypothesized that FP could rescue cerebral ischemia in rats. Methods : The present study was carried out to investigate the effects of FP on cerebral ischemia in terms of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in rats. Finally, lactate dehydrogenase (LDH) release was investigated, too. Results : In this study, treatment with FP elevated rCBF and MABP levels in dose-dependent manner. Pre-treatment with indomethacin, an inhibitor of cyclooxygenase, inhibited rCBF increase induced by FP effectively. However, FP did not affect stability during cerebral reperfusion. Finally, FP significantly inhibited LD H activity in vitro Conclusions : These results suggest that FP is useful to treat patient with diseases related to cerebral ischemia, because FP can increase rCBF and MABP.

• 한국세라믹학회지
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• 제32권7호
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• pp.777-782
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• 1995

The scale up production test for the hydrothermal synthesis of clay mineral from the anorthite, which is distributed in San Chung-District of Korea and called as the ground rock for halloysite-kaolin, has been investigated by using the gaitator type reactor. The automatic control system has been developed and applied for the more effective producibility and the reduction in the defect of this intermittent batch processing property, and finally for the feasibility of this system in actual use. It was observed that this agitator type reactor can reduce the synthesis reaction tme from 5 days to 3 days, only with the condition of 20rpm. The automatic control system could regulate the vessel temperature and pressure precisely at an optimum condition during the treatment. Therefore, from these test results the application-possibility for this system was found to be feasible in actual use.

• 설비공학논문집
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• 제29권1호
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• pp.38-42
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• 2017

This study proposes an idea for energy saving in apartment machine rooms. A conventional district heating system is equipped with constant-flow pumps and bypass valves to regulate pump differential pressure. Each family unit is equipped with a constant-flow on/off valve. This leads to excessive hot water circulation and a high return temperature. To reduce energy loss, this study assumes that each family unit is renovated with a heating valve which regulates the return temperature at $35^{\circ}C$. The hot water supply pump is also replaced with a pump with an inverter to vary flow rate. Expected energy savings is then estimated from field test data. According to the results, pump electricity consumption was reduced by 6,100 kWh for a family unit building over about half a year. The supply temperature can also be lowered by $5^{\circ}C$, which can contribute to a production of electricity of 10.3 kWh/ton of hot water.

• Nuclear Engineering and Technology
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• 제54권3호
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• pp.849-859
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• 2022

Feed-water valves (FWVs) are used to regulate the flow rate of water entering steam generators, which are very important devices in nuclear power plants. Due to the working environment of relatively high pressure and temperature, there is strength failure problem of valve body in some cases. Based on the thermo-fluid-solid coupling model, the valve body stress of the feed-water valve in the opening process is investigated. The flow field characteristics inside the valve and temperature change of the valve body with time are studied. The stress analysis of the valve body is carried out considering mechanical stress and thermal stress comprehensively. The results show that the area with relatively high-velocity area moves gradually from the bottom of the cross section to the top of the cross section with the increase of the opening degree. The whole valve body reaches the same temperature of 250 ℃ at the time of 1894 s. The maximum stress of the valve body meets the design requirements by stress assessment. This work can be referred for the design of FWVs and other similar valves.

• 대한한의학회지
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• 제27권4호
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• pp.198-208
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• 2006

Background : Ginseng has traditionally been used in oriental countries to recover vital energy from Qi deficiency, and has shown various biomedical effects in the scientific literature. Recent reports suggest that ginseng could regulate blood pressure (BP), but much controversy still remains. Therefore, we intended to assess the anti-hypertensive effect of several ginseng types frequently used in clinics. We also investigated the anti-hypertensive effect on Koreans and Chinese, and by the body type according to Sasang Constitution Medicine (SCM). Methods : The study subjects were recruited from mildly hypertensive patients who exhibited pre-hypertension(120/80 to 139/89 mmHg) and stage I hypertension (140/90 to 159/99 mmHg) in Korea and China. After assigning the subjects into a Korean, a Chinese, a red, and an American ginseng group by randomization, we prescribed ginseng at a dose of 4.5 g per day for 4 weeks. To assess the anti-hypertensive effect, we compared the mean of systolic and diastolic BP between before and after ginseng medication using a 24-hour ambulatory blood pressure monitor (24 hr ABPM. We also monitored adverse effect and laboratory findings to secure the subjects' safety. In addition, all of the subjects in Korea consulted a specialist of Sasang Constitution Medicine to identify their constitutional type. Results : There were 64 subjects treated with Korean ginseng, 58 treated with Chinese ginseng, 33 treated with red ginseng, and 64 treated with American ginseng. Korean, Chinese, and American ginseng all reduced subjects' BP; Korean and Chinese ginseng showed more effect. The secondary analysis on the subjects' nationality revealed that all of the ginseng types showed more significant anti-hypertensive effect in Chinese patients than in Koreans. The third analysis on the constitutional type of SCM showed there was no significant difference in the effectiveness and the safety of ginseng among the constitutional types. Conclusions : We suggest ginseng, especially Panax ginseng without any steaming-drying process, could be useful for mild hypertension. Further, ginseng is safe regardless of subjects' constitutional type or type of ginseng within a dosage of 4.5g per day.

• 한국산학기술학회논문지
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• 제17권7호
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• pp.734-739
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• 2016

선형으로 움직이는 글로브 밸브의 목적은 주로 유량을 제어할 수 있도록 설계 되어 있으며, 디스크의 움직임으로 인해서 유량을 제어가 가능하게 된다. 본 논문은 유량계수를 예측하기 위해서 전산유동해석 프로그램인 ANSYS-CFX로 유동해석을 진행 하였고 본 해석에서 사용되는 글로브 밸브 모델을 시제품과 동일한 형상의 크기로 설계하였다. 유량계수는 밸브 전개 시 $16.5^{\circ}C$의 맑은 물이 전후의 압력차 1psi로 흐를 때 그때의 유량을 말한다. 다시 말해서 밸브의 크기를 결정할 수 있는 중요한 요인이 된다. 밸브의 유량계수와 유량을 해석을 통해서 얻어낼 수 있었고, 그 해석으로 인해서 분당 0~0.1gal 유량을 제어할 수 있는 정밀제어 글로브 밸브를 개발 할 수 있었다. 유동해석과 실험의 결과로 유량계수를 서로 비교하였으며 그 결과로 인해서 유량계수의 오차율이 매우 작음을 확인하였고, 해석의 신뢰성을 확보하였다. 따라서 실험 없이 해석만으로 충분히 유량계수의 경향성을 파악하는데 크게 어려움이 없음을 보여주었다.

• Clinical and Experimental Pediatrics
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• 제53권1호
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• pp.21-27
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• 2010

목 적 : 인공호흡기 사용과 관련된 폐손상에 대한 연구가 활발히 이루어져 왔다. 특히 전통적 압력조절방식의 인공호흡기 사용시 발생하는 용적손상의 중요성이 밝혀지면서 신생아 호흡 곤란 증후군의 치료에서 용적조절방식의 인공호흡기가 부각되고 있다. 이에 저자들은 신생아 호흡곤란 증후군 환아를 대상으로 전통적 압력조절방식의 SIMV와 용적조절방식을 바탕으로 한 PRVC를 비교분석하고자 하였다. 방 법 : 2007년 5월부터 2008년 4월까지 대구파티마병원 신생아 중환자실에 입원한 환아중 출생 체중이 1,500 g 미만이고 신생아 호흡곤란 증후군이 있어 기도삽관에 의한 인공호흡기 치료 및 폐표면 활성제를 투여한 환아 34명을 대상으로 하여 PRVC 사용군 14명, SIMV 사용군 20명으로 나누어 비교하였다. 폐표면 활성제 투여 후 시간경과에 따른 PIP값의 변화, 감압된 PIP의 누적값, 기도발관까지의 기간, 그리고 전체 인공호흡기 사용기간을 조사하였고, 주요 합병증인 폐외 공기 누출, 기관지폐 이형성증, 폐고혈압, 미숙아 망막증, 뇌실내 출혈, 동맥관 개존증의 빈도를 조사하였다. 결 과 : 재태연령, 출생시 체중, 성별, 극소 저출생 체중아 비율, 1분 및 5분 Apgar 점수, 호흡 곤란 증후군 등급, 폐표면 활성제 투여 횟수 및 분만 방법, 산모의 임신성 고혈압, 조기양막파수 유무에서 두 군간의 임상적 특성 차이는 없었다. 폐표면 활성제 투여 전 및 투여 후 48시간까지의 PIP값은 PRVC군에서 보다 낮게 측정되었고, 투여 후 24시간까지 PRVC군에서 PIP의 감압이 더 잘 이루어 졌다(P<0.05). 기도발관까지 걸린 시간과 전체 인공호흡기 사용기간, 합병증의 발생 빈도 및 퇴원시점까지 소요된 시간 비교에서는 의미있는 차이는 없었다. 결 론 : SIMV군에 비해 PRVC군에서 PIP 값이 낮고, 폐표면 활성제 투여 후 감압이 더 잘 이루어졌다. 급변하는 폐유순도에 상응하는 감압에 있어 PRVC군이 더 유리하다고 볼 수 있다. 호흡기 이탈기간 및 합병증의 발생에 있어 차이는 없었으나, 잠재적인 폐의 용적손상과 관련 기존 SIMV군에서 필요 이상의 PIP가 설정되었던 것으로 생각되는 바, 이는 앞으로 더 많은 연구가 필요할 것으로 사료된다.

• 대한한방내과학회지
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• 제25권2호
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• pp.277-287
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• 2004

Objective : Diabetes is a disease in which the body does not produce or properly use insulin. Etiological studies of diabetes and its complications showed that oxidative stress might playa major role. Therefore, many efforts have been made to regulate oxygen free radicals for treating diabetes and its complications. Because Jindangwon has been known to be effective in treatment of diabetes, the methanol extract of Jindangwon was tested for its effectiveness in reducing the oxidative stress induced by Streptozotocin. Methods : Jindangwon was washed, dried in the shade and crushed. The crushed Jindangwon was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 hours. The extract was filtered and evaporated under reduced pressure using a rotary evaporator to yield 30.6 g. Jindangwon extract was oral-administered to the diabetic rats induced by streptozotocin 50 mg per 1 kg of body weight for 15 days. The efficacy of the Jindangwon extract was examined with regard to the enzymatic pathways involved in the oxygen free radical production and the glutathione balance. Results : he effects of the methanol extract of Jindangwon in streptozotocin-induced diabetics rats with regard to body weight, blood glucose level, hepatic lipid peroxide level, hepatic xanthine oxidase activity and type conversion rate, hepatic glutathione level, hepatic glutathione peroxidase activity, hepatic glutathione reductase activity, hepatic aldose reductase activity, and hepatic sorbitol dehydrogenase activity were favorable enough to suggest that it is a cure for diabetes and its complications. Conclusions :These results support Jindangwon as an effective reducing agent for oxidative stress in the tissues and organs by regulating the production of oxygen free radicals. Jindangwon, in particular, shows promising results for its use as a cure, or preventative medicine for diabetes and its complications by reducing oxidative stress in beta-cells of the pancreas.

• 한국추진공학회지
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• 제18권2호
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• pp.27-34
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• 2014

넓은 비행마하수와 받음각 기동 조건에서 고정된 형상을 가지는 초음속 흡입구에 안정되고 높은 압축비의 공기를 공급할 수 있는 제어기법을 제안하였다. 다양한 선행연구 결과 분석을 통하여 가장 현실적으로 적용하기에 용이한 제어변수를 도출하였고, 이를 비행조건에서 스케줄링 하여 사용할 수 있는 방법을 제시하였다. 제안된 스케줄링 및 흡입구 전압력 회복율 제어기를 추진기관 모델과 결합하여 시뮬레이션 함으로써 다른 제어변수에 비해 광범위한 비행영역에서 운용하기에 적합한 방법임을 보였다. 아울러 다양한 비행 조건에서의 제어기의 안정화 및 추종 성능을 시뮬레이션 함으로써 엔진의 동적 특성과 비행 기동역학 및 외란에 의해 나타나는 특성에 대해 살펴보았다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.127-127
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• 2018

Probiotics are microorganisms that have beneficial effects on the health of the host. The health promoting effect by probiotics influences suppressing harmful bacteria, prevention of constipation, blood cholesterol reduction and regulation of blood pressure. Prebiotics are used to promote the growth or activity of microorganisms. Synbiotics, which are a mixture of probiotics and prebiotics, synergize in the intestines by complementing each other. Synbiotics not only improves the viability of the probiotics while passing through the gastrointestinal tract, maintain intestinal homeostasis, but also regulate balance of harmful and useful bacterial growth. Glycine max Merr (GMM) has been widely used in Asian countries to treat cancer, obesity, oxidative stress and imbalanced immune diseases. In addition, it has been reported that dietary fiber-rich grains promote bowel movements and prevent constipation. In this study, we investigated the viability of LactobacillIus buchneri (L.buchneri) strains, known as lactic acid bacteria under conditions of gastric fluid and intestinal fluid to determine the suitability of L.buchneri as probiotics. The adhesion ability of L.buchneri to caco-2 cells was also confirmed. The present studies showed that GMM extract promoted the growth and activity of L.buchneri strains as prebiotics. Also, this results suggested that the mixture of L.buchneri and GMM extract can helps maintain intestinal health and healthy body as synbiotics and health functional food material.