• 동력기계공학회지
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• 제15권5호
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• pp.22-29
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• 2011

In this study, the damage mechanism of large scale steam turbine due to water induction was analyzed and recovery characteristics were reviewed. A turbine consists of the rotating rotor and the stationary casing, and the clearance between them is very small for the efficiency enhancement. If water induction, while relatively cold steam or water is introduced into turbine, occurs, the considerable humping is caused at the casing near the initial water induction point and that induces the rubbing between rotor and casing. Finally, it leads to the catastrophic failure. Bowed rotor has the different characteristics in the recovery depending on damage degree. The elastic deformation due to light rubbing is recovered by turning the rotor with 3 rpm under normal operation condition, but most plastic deformation due to rubbing deforms the local microstructure and that results in permanent deformation which could not be recovered under normal operation condition. Bowed rotor has diverse characteristics depending on the recovery method, and the method is empirical and needs the cutting edge technology. Careful recovery treatment of the rotor will eliminate the risks and secure the high quality rotor similar to new rotor. If any critical error is made during the recovery, the rotor would not be recovered permanently and it should be scrapped.

• 한국식품과학회지
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• 제41권5호
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• pp.587-591
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• 2009

무처리(R), 수증기 증류처리(SD), 동결건조 후 수증기 증류 처리(FD/SD)한 사자발쑥과 일반 쑥의 휘발성분을 HS-SPME방법으로 추출 후 GC-MS로 동정하였다. 무처리 사자발쑥 및 동결건조 후 수증기 증류 처리한 사자발쑥의 총 volatile함량은 각각의 일반 쑥 시료보다 유의적으로 높았으며(p<0.05), 무처리 일반 쑥의 수증기 증류처리 시료의 경우에는 유의적인 차이가 없었다(p>0.05). 무처리 사자발쑥의 주요 휘발성분은 2-hexenal, 1,8-cineol, transcaryophyllene, hexanal이었고 무처리 일반 쑥은 1-hexanol, ${\beta}$-myrcene, limonene, 2-hexenal이었다. 반면에 수증기 증류처리(SD) 및 동결건조 후 수증기 증류처리(FD/SD)된 사자발쑥에서는 1,8-cineole, 4-terpineol, 1-octen-3-ol, ${\alpha}$-terpineol이, 수증기 증류처리(SD) 및 동결건조 후 수증기 증류처리(FD/SD) 된 일반 쑥의 경우에는 1,8-cineol, camphor, borneol, artemisia ketone, ${\alpha}$-thujone, 1-octen-3-ol이 주요 휘발성분이었다. 무처리 쑥의 경우 지방산화에 의해 발생하는 이취성분인 2-hexenal, hexanal과 1-hexanol이 많이 검출되었으나 수증기 증류처리(SD) 및 동결건조 후 수증기 증류처리(FD/SD) 된 시료는 정유성분 유래 휘발성분이 상대적으로 많이 검출되었다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2000년도 추계학술대회 및 발표대회 강연 및 발표논문 초록집
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• pp.27-28
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• 2000

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2003년도 춘계학술발표회 초록집
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• pp.38-40
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• 2003

• 한국식품영양과학회지
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• 제35권5호
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• pp.649-654
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• 2006

품종별 무청의 표면 미생물 분포와 중심합성계획과 반응 표면분석법을 이용하여 물세척, 마이크로웨이브처리 및 스팀처리를 독립변수로 두고, 이들 전처리 조건에 따른 표면미생물의 변화를 조사하였다. 그 결과 무청 품종에 관계없이 병원성 미생물인 Salmomella spp., Camphylobacter spp., Vibrio spp., Shigella spp., Staphylococcus spp., Enterococcus spp. 및 Pediococcus spp.는 전혀 검출되지 않았다. 그러나 총균수의 경우는 품종에 따라 약간의 차이는 있었는데, $3.90{\times}10^5{\sim}1.20{\times}10^7CFU/g$의 범위를 보였고, 대장균군은 $1.10{\times}10^2{\sim}2.00{\times}10^5CFU/g$, 효모/곰팡이는 $2.40{\times}10^3{\sim}3.55{\times}10^6CFU/g$을 보인 반면 젖산균은 검출되지 않은 시료도 있었다. 또 전처리 방법에 따른 무청의 잔존 미생물의 감균 효과가 가장 좋은 전처리 방법은 스팀처리 방법이었다. 원료 무청의 각각의 전처리 방법을 독립변수(independent variables)로 하고, 총균수, 젖산균수 및 효모/곰팡이균수를 종속변수(dependent variables)로 하여 회귀 분석한 결과 상관관계를 나타내는 $R^2$값이 각각 0.89, 0.87, 0.85로 상관성이 높았으며, 물세척 횟수에 의한 감균 효과는 제한적이므고 마이크로웨이브처리나 스팀처리를 병행하여야 효과적이었다.

• 대한본초학회지
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• 제33권4호
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• pp.87-93
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• 2018

Objectives : The prevalence of infertility is reported to be 23.3%, which is a serious social problem. Habitual abortion is one of the important complications during pregnancy. The purpose of this study is to help the treatment of habitual abortion by observing and reporting the process in which four women who did not have children due to habitual abortion make healthy birth through treatment. Methods : We administered Jokyungjongok-tang gamibang as a herbal medicine treatment method and treated with acupuncture, moxibustion and uterine steam treatment. Treatment was done once or twice a week but it was also varied depending on the patient's circumstances. The herbal medicines were taken 30 minutes after meals and 3 times a day. While taking the Korean medicine, they were prohibited from eating flour, pork, liquor, tobacco and coffee. Patient status was assessed by consultation through pulse, tongue and abdomen. A detailed questionnaire was performed for each treatment. In some cases, they have tested hormone levels at the hospitals to know ovulation dates. The diagnosis of pregnancy was confirmed by ultrasonography at hospitals and the treatment for habitual abortion was judged based on healthy birth. Results : As a result of herbal medicine, acupuncture, moxibustion and uterine steam treatment, the coldness of the body became weak, the fatigue decreased and the digestive condition gradually began to improve. The bad condition of the uterus caused by the repeated administration of heritage has been improved with Boheosaenghwa-tang gamibang. After administration of Jokyungjongok-tang gamibang, they became pregnant and overcame the condition of addictive abortion and gave birth to healthy children. Conclusion : Jokyungjongok-tang gamibang is effective in overcoming the symptoms of habitual abortion and giving birth to a healthy child for a woman who had no children due to her habitual abortion

• 한국안전학회지
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• 제32권2호
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• pp.1-6
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• 2017

Modern society has been experiencing by population growth and urbanization that bring, a change of eating habits which has occurred a various types of waste in a large amount. Even though these wastes are required an immediate treatment with difficulties unsanitary handling and existing waste treatment method are by incineration, fermentation, drying and etc. however a bad smell occurs after the treatment that need's a lot of energy in processing organic wastes with high moisture contents and wasteful and inefficient problem. The strength assessment of the organic waste agitating vessel is required in terms of safety due to the differences of loading on the shaft that was treated by agitating the mixture of food waste. The damage of agitating axis is depended on steam pressure, temperature condition and the force moment that exerted by the food waste. Thus the strength assessment and stability evaluation are very important, especially to handle a hard waste. In this study the rotation capacity of agitation is about 5 tons considering general structural rolled steel pressure vessel strength and steam pressure. The purpose is to estimate the safety and strength evaluation for a agitator axis and impellers according to the rotating angle of the axis under the condition of the 3.2 ton capacity reactor.

• Journal of Photoscience
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• 제8권1호
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• pp.19-22
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• 2001

It was reported that Red ginseng contains specific ginsenoside-Rg$_2$,-Rg$_3$,-Rh$_1$and -Rh$_2$, which show various pharmacological effects. However, production of these specific ginsenosides from Red ginseng is not commercially applicable because of high cost of the raw material, roots. This work was carried out to examine the production of Red ginseng specific ginsenosides from Agrobacterium-transformed hairy roots. Hairy roots were induced from 3 year-old root segment of Korean ginseng (Panax ginseng C.A. Meyer) after infection with Agrobacterium rhizogenes A4. Among many lines of hairybroots, KGHR-8A was selected. Steam heat treatment of hairy roots was resulted in the changes of ginsenoside composition. Eleven ginsenosides were detected in heat-treated hairy roots but eight in freeze dried hairy roots. In heat treated hairy root, content of ginsenoside-Rb$_1$,Rb$_2$,Rc, Rd, Re, Rf, and Rg$_1$were decreased compared to those of freeze dried hairy roots. However, heat treatment strongly enhanced the amount of Red ginseng specific ginsenogides (ginsenoside-Rg$_2$,-Rg$_3$,-Rh$_1$and -Rh$_2$). Amounts of ginsenoside-Rg$_3$,-Rh$_1$and -Rh$_2$ in heat-treated hairy roots were 2.58, 3.62 and 1.08 mg/g dry wt, respectively, but these were detected as trace amount in hairy roots without heat treatment. Optimum condition of heat treatment for the production of Red ginseng specific ginsenoside was 2 h at 105$^{\circ}C$. This result represents that Red ginseng specific ginsenoside can be producted from hairy roots by steam heat treatment.

• 한국과학교육학회지
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• 제35권6호
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• pp.1007-1018
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• 2015

21세기 지식 기반 정보화 사회에서 융합인재교육이 요구하는 과학기술 인재는 복잡한 문제 현상을 이해하고 해결하기 위해서 시스템 사고 능력이 중요하게 요구된다. 이 연구는 시스템 사고를 기반으로 한 융합인재교육 프로그램을 개발하고, 고등학생에게 적용하여 시스템 사고에 미치는 효과를 검증하는 데 그 목적이 있다. Park & Lee(2014)의 ADBAS 모형을 적용하고 물레방아를 주제로 개발된 프로그램을 고등학생 60명을 대상으로 투입하여 효과를 검증하였다. 그 결과 시스템 사고 능력에 대하여 양적 효과와 질적 효과 모든 측면에서 향상된 것을 확인하였다. 따라서 학생들의 시스템 사고 능력과 창의적 문제 해결 능력을 위해 시스템 사고 기반의 융합인재교육 프로그램을 투입하기에 적절한 것으로 판단되며, 교육 현장에서 융합인재를 양성하는데 활용될 수 있을 것으로 기대 된다.

• Journal of the Korean Wood Science and Technology
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• 제44권5호
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• pp.776-784
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• 2016

본 연구에서는 pilot scale에서 과열증기를 이용하여 실대재 낙엽송 생재 각재를 열처리하고, 열처리된 낙엽송재의 다양한 물리 역학적 성능과 내후성능을 측정하였다. 또한, 이를 고온 열기 열처리한 낙엽송재의 물성과 비교하였다. 생재로부터 할렬 발생이 억제된 상태로 과열증기 열처리된 낙엽송재의 갈색부후균과 백색부후균에 대한 저항성과 종압축강도는 증가한 반면에 밀도와 평형함수율 및 수축률과 휨강도는 관행 열처리재보다 낮게 측정되었다. 과열증기 목재 열처리는 다량의 수분에 의해 열전달이 빠르고 열가수분해가 촉진되기 때문에 유사한 시간과 온도에서 열기를 이용하여 관행 열처리한 경우보다 열처리 효과가 높게 나타났다. 따라서 과열증기 열처리 방법은 생재를 할렬 없이 열처리할 수 있으며, 관행 열처리 방법보다 낮은 온도 또는 짧은 열처리 시간으로도 동일한 열처리 효과를 발현시킬 수 있다. 즉, 열처리에 소요되는 시간과 에너지를 줄일 수 있다.