• 한국의학물리학회지:의학물리
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• 제14권3호
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• pp.175-183
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• 2003

최근 선량측정의 정확성을 향상시키기 위하여 기존의 공기커마 교정인수에 기반한 표준측정법에서 물 흡수선량 교정인수에 기반한 표준측정법으로 변환하고 있는 추세이다. 본 연구에서는 미국의학물리학회의 AAPM TG-51과 국제원자력기구의 IAEA TRS-398 표준측정법에 대한 선량교정 프로그램을 개발하였다. 이 프로그램은 윈도우 환경에서 사용이 용이하도록 비쥬얼 C++언어를 사용하여 각각의 표준측정법에서 권고하고 있는 방법 및 절차에 따라 사용자의 편의성을 고려하여 개발하였다. 이 프로그램은 이온함에 대한 정보와 물리적인 자료에 대한 표와 그래프 값들을 수식화하여 데이터베이스화함으로써 수작업으로 인해 발생할 수 있는 실수 및 오차를 줄일 수 있다. 개발된 프로그램의 활용을 통하여 국내 실정에 적합한 물 흡수선량 표준에 기반한 표준측정법 개발에 토대를 마련하는데 있어 기여할 것으로 사료된다.

• 동의생리병리학회지
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• 제27권2호
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• pp.196-201
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• 2013

Abnormal regulation of glucose and impaired lipid metabolism that result from a defective or deficient insulin are the key etiological factor in type 2 diabetes mellitus (T2DM). The our study evaluated the beneficial effect of diet supplementation with Lentinus edodes on hyperglycemia and lipid metabolism in normal and type 2 diabetic rats. The animals were divided into 4 groups: group I(control) rats were fed standard diet (12% of calories as fat); group II (T2DM) rats were fed HFD (40% of calories as fat) for 2 weeks and then injected with STZ (50 mg/kg); group III and group IV rats were continually fed a diet containing 1% and 10% Lentinus edodes for 4 weeks after T2DM induction, respectively. After 4 weeks we determined biochemical parameters such as glucose, insulin concentration, serum total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), and glycosylated hemoglobin (HbA1c) concentration were also measured. There was a significant reduction in serum TC and TG in the Lentinus edodes supplement groups. The Lentinus edodes diet supplementation were found to have a potent lipid metabolism improvement as well as LDL concentration decreased and HDL concentration was increased. Concentrations of blood glucose and HbA1c in the experimental groups II were significantly decreased after 4 weeks compared with the control group. The Lentinus edodes diet supplementation is useful in regulating the glucose level, improves the insulin, HbA1c, serum lipid metabolism in experimental diabetic rats. We suggest that Lentinus edodes supplementation may have the control effects of diabetes mellitus by improving blood glucose control and lipid metabolism.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2000년도 Proceedings of 5th International Joint Symposium on Microeletronics and Packaging
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• pp.9-15
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• 2000

Flip chip assembly on organic substrates using ACAs have received much attentions due to many advantages such as easier processing, good electrical performance, lower cost, and low temperature processing compatible with organic substrates. ACAs are generally composed of epoxy polymer resin and small amount of conductive fillers (less than 10 wt. %). As a result, ACAs have almost the same CTE values as an epoxy material itself which are higher than conventional underfill materials which contains lots of fillers. Therefore, it is necessary to lower the CTE value of ACAs to obtain more reliable flip chip assembly on organic substrates using ACAs. To modify the ACA composite materials with some amount of conductive fillers, non-conductive fillers were incorporated into ACAs. In this paper, we investigated the effect of fillers on the thermo-mechanical properties of modified ACA composite materials and the reliability of flip chip assembly on organic substrates using modified ACA composite materials. For the characterization of modified ACAs composites with different content of non-conducting fillers, dynamic scanning calorimeter (DSC), and thermo-gravimetric analyzer (TGA), dynamic mechanical analyzer (DMA), and thermo-mechanical analyzer (TMA) were utilized. As the non-conducting filler content increased, CTE values decreased and storage modulus at room temperature increased. In addition, the increase in tile content of filler brought about the increase of Tg$^{DSC}$ and Tg$^{TMA}$. However, the TGA behaviors stayed almost the same. Contact resistance changes were measured during reliability tests such as thermal cycling, high humidity and temperature, and high temperature at dry condition. It was observed that reliability results were significant affected by CTEs of ACA materials especially at the thermal cycling test. Results showed that flip chip assembly using modified ACA composites with lower CTEs and higher modulus by loading non-conducting fillers exhibited better contact resistance behavior than conventional ACAs without non-conducting fillers.ers.

• 마이크로전자및패키징학회지
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• 제7권1호
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• pp.41-49
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• 2000

Flip chip assembly on organic substrates using ACAs have received much attentions due to many advantages such as easier processing, good electrical performance, lower cost, and low temperature processing compatible with organic substrates. ACAs are generally composed of epoxy polymer resin and small amount of conductive fillers (less than 10 wt.%). As a result, ACAs have almost the same CTE values as an epoxy material itself which are higher than conventional underfill materials which contains lots of fillers. Therefore, it is necessary to lower the CTE value of ACAs to obtain more reliable flip chip assembly on organic substrates using ACAs. To modify the ACA composite materials with some amount of conductive fillers, non-conductive fillers were incorporated into ACAs. In this paper, we investigated the effect of fillers on the thermo-mechanical properties of modified ACA composite materials and the reliability of flip chip assembly on organic substrates using modified ACA composite materials. For the characterization of modified ACAs composites with different content of non-conducting fillers, dynamic scanning calorimeter (DSC), and thermo-gravimetric analyser (TGA), dynamic mechanical analyzer (DMA), and thermo-mechanical analyzer (TMA) were utilized. As the non-conducting filler content increased, CTE values decreased and storage modulus at room temperature increased. In addition, the increase in the content of filler brought about the increase of $Tg^{DSC}$ and $Tg^{TMA}$. However, the TGA behaviors stayed almost the same. Contact resistance changes were measured during reliability tests such as thermal cycling, high humidity and temperature, and high temperature at dry condition. It was observed that reliability results were significantly affected by CTEs of ACA materials especially at the thermal cycling test. Results showed that flip chip assembly using modified ACA composites with lower CTEs and higher modulus by loading non-conducting fillers exhibited better contact resistance behavior than conventional ACAs without non-conducting fillers.

• Fisheries and Aquatic Sciences
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• 제22권11호
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• pp.27.1-27.6
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• 2019

Background: In order to assess the high value-added use of the alginate-free residue of sea tangle, an animal study was performed to evaluate the functional activities and key compounds present. In the animal study, sea tangle and the alginate-free residue demonstrated good anti-hyperlipidemic and anti-arteriosclerotic abilities. Results: The functional compounds in the alginate-free residue of the sea tangle were effectively extracted by supercritical fluid extraction (SFE). The optimum extraction temperature and pressure were 40 ℃ and 6500 psi (M1) in the SFE, a better method in comparison to the conditions of 70 ℃ and 4500 psi (M2), respectively. The anti-atherosclerotic effects of the alginate-free residue of sea tangle (M1, M2) were investigated in Sprague-Dawley rats treated with poloxamer 407, Triton WR 1339, corn oil, and a high-fat diet. The M1 fraction reduced the serum lipid levels with greater efficacy than the M2 fraction. In the hyperlipidemic rats, treatment with M1 decreased the serum triglyceride (TG), total cholesterol (TC), and low-density lipoprotein-cholesterol (LDL-C) levels when compared to the levels in normal rats. Conclusion: Our results demonstrated that the alginate-free residue of sea tangle reduces serum TC, TG, and LDL-C. These results suggest that the alginate-free residue of sea tangle contains physiologically active components, such as fucosterol, that may exert beneficial effects in the prevention of atherosclerosis.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.665-670
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• 2003

우라늄 변환시설 내의 lagoon 슬러지의 처리 공정에서 발생하는 고농도 질산염 폐액의 처리를 위해 질산염 폐액의 열역학 및 열분해 특성을 조사하였다. 열역학적 특성은 고농도 질산염 폐액의 조성을 바탕으로 COACH와 GEMINKI II를 사용하여 조사하였으며, 열분해 특성은 TG/DTA, XRD 분석을 통하여 실제 질산염 폐액에 대하여 조사하였다. 폐액 내 함유 성분 중 $NH_4NO_3$는 $^250{\circ}C$에서 모두 분해되었으며, 잔류물의 대부분을 차지하는 $NaNO_3$는 $730^{\circ}C$에서 분해되는 것으로 나타났다. $NaNO_3$의 분해생성물인 불안정한 $Na_2O$를 안정한 화합물로 변화시켜 주기 위하여 $Al_2O_3$를 첨가할 경우 $NaNO_3$는 $450^{\circ}C$의 낮은 온도에서 분해 가능하였다. 이 같은 열역학 및 열분해 특성을 바탕으로 고농도 질산염 폐액의 처리 공정도를 제시하였으며, 특성 자료는 공정 모사의 기초 자료로 활용될 것이다.

• 한국구조물진단유지관리공학회 논문집
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• 제16권4호
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• pp.1-8
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• 2012

본 연구에서는 실물모형 화재시험 후 쉴드터널 라이닝의 손상평가를 수행하였다. 먼저 고온에 노출된 쉴드터널 라이닝의 코어 채취를 통해 잔존압축강도를 측정하고, X선 회절분석 및 열중량 분석으로 수열온도를 예측하였다. 코어 채취에 의해 측정된 잔존 압축강도를 통해 고온에 의한 부재의 강도저하를 평가할 수 있었다. 또한 정확한 수열온도 예측이 이루어진다면 기존의 연구결과를 통해 부재의 잔존압축강도를 추정할 수 있다. X선 회절분석 및 열중량 분석은 약 $450^{\circ}C$의 온도를 기준으로 수열온도 예측이 가능하지만 정량적인 수열온도의 판단에는 한계가 있었다. $400{\sim}600^{\circ}C$의 수열온도범위에서는 기기분석에 의한 평가와 더불어 해석적 기법이 병행된다면 보다 정확한 수열온도 예측이 가능할 것이다.

• 대한지역사회영양학회지
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• 제16권1호
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• pp.126-135
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• 2011

Obesity is characterized by increased storage of fatty acids in an adipose tissue and closely associated with the development of insulin resistance and cardiovascular diseases (CVD) through secretion of adipokines. This study was done to compare serum insulin, leptin, adiponectin and high sensitivity C-reactive protein (hs-CRP) levels according to body masss index (BMI) in Korean adult women aged 19 to 50. In addition, we examined the association of BMI, serum lipids and Homa-IR with serum adiponectin, leptin and hs-CRP levels. The subjects were divided into 3 groups by their BMI, normal weight (BMI ${\leq}$ 22.9, n = 30), overweight (23.0 ${\leq}$ BMI ${\leq}$ 24.9, n = 71) and obese group (25.0 ${\leq}$ BMI, n = 59). Serum levels of total-cholesterol, TG, and LDL-cholesterol were significantly higher in obese group than in normal weight group. LDL/HDL ratio and AI were significantly higher in obese group than in normal or overweight group. Fasting serum levels of glucose and insulin and Homa-IR as a marker of insulin resistance were significantly higher in obese group than in overweight group. Serum leptin level was significantly higher in obese group while serum adiponectin level was significantly lower in obese group compared to other two groups. hs-CRP was significantly increased in obese group. Correlation data show that serum adiponectin level was positively correlated with serum HDLcholesterol level and was negatively correlated with BMI, WC, TG, LDL-cholesterol, Homa-IR, hs-CRP and leptin. In addition, serum leptin level was positively correlated with BMI, WC, glucose, insulin, Homa-IR and hs-CRP. These results might imply that the regulation of key adipokines such as adiponectin might be a strategy for the prevention or treatment of obesity-associated diseases such as diabetes and CVD.

• Korean Chemical Engineering Research
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• 제56권2호
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• pp.275-280
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• 2018

Methyl ester derived from coconut oil is very interesting to study since it contains free-fatty acid with chemical structure of medium carbon chain ($C_{12}-C_{14}$), so the methyl ester obtained from its part can be a biodiesel and another partially into biokerosene. The use of heterogeneous catalysts in the production of methyl ester requires severe conditions (high pressure and high temperature), while at low temperature and atmospheric conditions, yield of methyl ester is relatively very low. By using microwave irradiation trans-esterification reaction with heterogeneous catalysts, it is expected to be much faster and can give higher yields. Therefore, we studied the production of methyl ester from coconut oil using CaO catalyst assisted by microwave. Our aim was to find a kinetic model of methyl ester production through a transesterification process from coconut oil assisted by microwave using heterogeneous CaO catalyst. The experimental apparatus consisted of a batch reactor placed in a microwave oven equipped with a condenser, stirrer and temperature controllers. Batch process was conducted at atmospheric pressure with a variation of CaO catalyst concentration (0.5; 1.0; 1.5; 2.0, 2.5%) and microwave power (100, 264 and 400 W). In general, the production process of methyl esters by heterogeneous catalyst will obtain three layers, wherein the first layer is the product of methyl ester, the second layer is glycerol and the third layer is the catalyst. The experimental results show that the yield of methyl ester increases along with the increase of microwave power, catalyst concentration and reaction time. Kinetic model of methyl ester production can be represented by the following equation: $-r_{TG}=1.7{\cdot}10^6{_e}{\frac{-43.86}{RT}}C_{TG}$.

• 동의생리병리학회지
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• 제19권2호
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• pp.466-474
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• 2005

Four kinds of decoctions (Wolbi-tang, Wolbigachul-tang, Wolbigabanha-tang and Wolbi-tang with Psyllium Husk diet)was prescribed to examined the therapeutic effects on hyperlipidemia. Four decoctions prepared from the prescriptions were respectively administrated to the corpulent rats induced by a high cholesterol diet. Wolbi-tang mollified the increasing rate of the body weight, and decreased the amount of food eaten. It slightly increased the concentrations of blood Tc, blood TG, blood FFA, and lipids in feces, and decreased the contents of blood HDL-c. Wolbigachul-tang mollified the increasing rate of the body weight, and decreased the amount of food eaten. It decreased the amount of FFA and HDL-c lipids in the blood. Wolbigabanha-tang mollified the increasing rate of the body weight, and decreased the amount of food eaten. Also, it decreased the concentrations of blood glucose. However, it increased the content of blood HDL-c. Wolbi-tang with Psyllium Husk diet mollified the increasing rate of body weight, and decreased the amount of food eaten. Also, it slightly decreased the concentrations of blood TG and blood FFA, but increased the concentrations of blood Tc. Considering the above results, four kinds of decoctions(Wolbi-tang, Wolbigachul-tang, Wolbigabanha-tang and Wolbi-tang with Psyllium Husk diet) could be applied for the treatment of obesity, and Wolbigabanha-tang would be the most recommendable among them.