• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.254-259
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• 2005

In this study, measurement of thermal conductivity of multilayer thin dielectric film has been conducted via differential 3$\omega$ method. Also, verification of differential 3$\omega$ method has been accomplished with various proposed criteria. The target film for measurement is 300 nm silicon dioxide and this thin film is covered with various thicknesses of upper protective layer. The upper protective layer is inserted between the target film and the heater line for purpose of electrical insulator or anti-oxidation barrier since the target film may be a good electrical conductor or a well-oxidizing material. However, the verification of differential 3$\omega$ method has not been conducted. Thus we have shown that the measurement of thermal conductivity of thin films with upper protective layer via differential 3$\omega$ method is verified to be reliable as long as the proposed preconditions are satisfied. Experimental results show that the experimental errors tend to increase with aspect ratio between upper protective layer thickness and width of the heater line due to heat spreading effect.

• Korean Journal of Materials Research
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• v.20 no.3
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• pp.161-166
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• 2010

The ac, dc conductivity and dielectric properties of $DyCoO_3$ were reported in the temperature range of 77 - 300K and in the frequency range of 20 Hz - 100 kHz. It was observed that at low temperature, ac conductivity is much higher than dc conductivity and the hopping carrier between localized states near the Fermi level was the dominant loss mechanism. A comparison of the measured ac conductivity $\sigma(\omega)$ was made with some of the models of hopping conductivity of the proposed earlier in the literature. It was observed that in $DyCoO_3$ the measured ac conductivity, over the entire frequency and temperature region, can be explained reasonably well by assuming two contributions $\sigma_1(\omega)$ and $\sigma_2(\omega)$ to the measured $\sigma(\omega)$. The first, $\sigma_1(\omega)$, which dominates at low temperature, may be due to impurity conduction in a small polaron; the second, $\sigma_2(\omega)$, which dominates at higher temperatures, depending on the frequency of measurements, may be due to the hopping of a small polaron and is reasonable for the dielectric relaxation peak.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.39-44
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• 2015

We investigated the effect of CNT-Ag composite pad on the contact resistance of flip-chip joints, which were formed by flip-chip bonding of Cu/Au chip bumps to Cu substrate metallization using anisotropic conductive adhesive. Lower contact resistances were obtained for the flip-chip joints which contained the CNT-Ag composite pad than the joints without the CNT-Ag composite pad. While the flip-chip joints with the CNT-Ag composite pad exhibited average contact resistances of $164m{\Omega}$, $141m{\Omega}$, and $132m{\Omega}$ at bonding pressures of 25 MPa, 50 MPa, and 100 MPa, the flip-chip joints without the CNT-Ag composite pad had an average contact resistance of $200m{\Omega}$, $150m{\Omega}$, and $140m{\Omega}$ at each bonding pressure.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.476-482
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• 2012

Estimations were made of oxidative susceptibility and fatty acid composition of edible meats of native chickens fed various dietary sources containing ${\omega}-3$ polyunsaturated fatty acids (PUFA). A total of 240 Korean native chickens were divided into 4 groups, placed into 3 replicates per group, and were fed a commercial diet (Control) or one of the three experimental diets containing 10% perilla meal (PM group), 10% perilla meal-5% full fat flaxseed (PM+FS group), or 10% perilla meal-5% full fat flaxseed-1% fish oil (PM+FS+FO group) for 20 days. Final body weight, weight gain, feed intake, and feed conversion rate among the groups were not significantly different. Dietary treatments did not affect the relative weights of liver, abdominal fat, and breast muscle. The leg weight was increased from the feeding of ${\omega}-3$ PUFA sources. The TBA reactive substance in the edible meat was not different with the dietary treatments. The total ${\omega}-3$ PUFA in chickens that were fed diets containing ${\omega}-3$ PUFA sources increased compared to that of the control. The level of longer chain ${\omega}-3$ PUFAs, such as C20:5 ${\omega}3$ and C22:6 ${\omega}3$ in the PM+FS+FO group, was much higher than that of the others. The addition of local ingredients, such as perilla meal with conventional sources, could be used to obtain value-enhanced meat by enhancing ${\omega}-3$ PUFA.

• Journal of the Korean Mathematical Society
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• v.31 no.3
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• pp.457-466
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• 1994

When we study complex analysis, we often encounter multi-valued functions. Provably the best known example would be $\sqrt{z}$, which has a singularity at the oritgin. In general, let $\Omega_1 and \Omega_2$ be domains in C, and let $\Gamma$ be a subvariety of $\Omega_1 \times \Omega_2$.

• Journal of Nutrition and Health
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• v.31 no.8
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• pp.1315-1323
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• 1998

Effect of oral taurine supplementation on plasma total and phospholidpid -fatty acid profiles and their metabolism were evaluated in healthy female adults. Among twenty five female volunteers(23.6$\pm$0.3 years old ) participated in the taruine supplementation program(6g taurine /day), twenty four subjects succesfully completed the 2 week program , and only nine subjects continued to take taurine for another 2 weeks. Levels of plasma fatty acids and taruine were measured by gas-liquid chromatobraphy and an automated amino acid analyzer based on ion exchange chromatography, respectively. Plasma taurine concentration s of the subjects were 108. 7$\pm$3.4 , 184.2$\pm$8.2 and 235.9$\pm$77.0$\mu$emol/L at 0 , 2 and 4 weeks of taurine supplementation. Fatty acid compositions and elongation and desaturation indices of polyunsaturated fatty acids (PUFA) in plasma total lipids were not influenced by oral taurine supplementation. However, fatty acid compositions and their metabolism in plasma phospholipids were significantly affected by taurine supplementation in female adults. Compared to the values for 0 week, the percentage of saturated fatty acids (SFA) in plasma phospholipid was significantly lowered at 2 weeks, but elevated at 4 weeks of taurine supplementation. In contrast , the percentage of phospholipid PUFA significantly increased at 2 weeks and decreased at 4 weeks of taurine supplementation from to the values for 0 weeks. Foru weeks of oral taurine supplementation signifinatly elevated the eongation index(20 : 4$\omega$6 ⇒22 : 4 $\omega$6, p<0.01), and decreased the desaturation index (20 : 3 $\omega$6 ⇒20 : 4 $\omega$6 , p<0.01) of $\omega$6 fatty acids in plasma phospholipids. Plasma taurine concentration was positively correlated with the percentage of 14 : 0 fatty acids and the enlongation index o f$\omega$3 fatty acids(20 : 5 $\omega$3 ⇒22 : 5 $\omega$3), and thenegatively correlated with the percentage of 20 : 0 in plasma phospholipids. These results indicate that oral taurine supplementation for 4 weeks signidicantly elelvated the percentage of SFA, and lowered the percentage of PUFA in plasma phospholipids with no influence on plasm total fatty aicd composition in healthy female adults.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.1
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• pp.98-104
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• 2020

Purpose: To investigate the impact of omega-3-enriched lipid emulsion (LE) on liver enzyme (aspartate transaminase [AST] and alanine aminotransferase [ALT]) and triglyceride (TG) levels of children undergoing gastrointestinal surgery. Methods: This experimental randomized controlled group pretest-posttest design study included 14 children who underwent gastrointestinal surgery due to duodenal atresia, jejunal atresia, esophageal atresia, and need for parenteral nutrition for a minimum of 3 days at RSUD Dr. Soetomo Surabaya between August 2018 and January 2019. These children were divided into two groups, those who received standard intravenous LE (medium-chain triglyceride [MCT]/long-chain triglyceride [LCT]) and those who received intravenous omega-3-enriched LE. Differences in AST, ALT, and TG levels were measured before surgery and 3 days after the administration of parenteral nutrition. Results: Liver enzyme and TG levels in each group did not differ significantly before versus 3 days after surgery. However, TG levels were significantly lower in the omega-3-enriched intravenous LE group (p=0.041) at 3 days after surgery, and statistically significant difference in changes in TG levels was noted at 3 days after surgery between MCT/LCT intravenous LE group and the omega-3-enriched intravenous LE group (p=0.008). Conclusion: The intravenous omega-3-enriched LE had a better TG-lowering effect than the MCT/LCT intravenous LE in children undergoing gastrointestinal surgery.

• The Korean Journal of Rheology
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• v.9 no.3
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• pp.89-96
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• 1997

PS/PPO 블렌등의 동적 탄성율 E*($\omega$)와 동적 스트레인-광학계수 O*($\omega$)을 유리전이 영역에서 동시에 측정하여, PS/PPO 3종류조성블렌드의 E*($\omega$)와 O*($\omega$)완화거동을 조성 단 일 중합체와 비교고찰하였다. PS/PPO 블렌드의 $\alpha$-분산 점탄성 거동은 조성에 관계없이 거 의 유사하여 조성 고분자가 상호 협동적으로 완화하는 것을 알수 있었다. 그러나 광학적 완 화 스펙트럼 O*($\omega$)는 정성적으로 명확히 다른 거동을 보였다. 단일 PS와 PPO의 O*($\omega$)는 전 영역에 걸쳐 상반된 부로를 나타냈으며 두 고분자의 블렌드는 조성고분자의 반대부호를 상호보상으로 인하여 복굴절이 감소하였다. 3종류블렌드는 PPO의 조성이 증가함에 따라 상 호보상에 의해 O*($\omega$)의부호가 순차적으로 변하여 반전하였으며, 저 복굴절 PS/PPO 블렌드 의 PS조성이 65-80wt% 범위내에 있음을 추정할수 있었다. 상이한 부호를 갖는 복굴절 특 성으로 인하여 블렌드 내에서 각 성분 고분자의 완화 기여를 다순 가성법칙에 의해 정량적 으로 계산하는 것이 가능하였다. 또한 PS/PPO 블렌드의 상용성을 광학적 부분 기여 파라메 터를 사용하여 고찰하였다.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.108-117
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• 1985

The process of conveying of soil with the open auger to cover the seed completly with less power was reviewed by theoretical analysis. The power efficiency, the reasonable range of RPM of the open auger and the velocity of soil conveying to the direction of the shaft are examined to establish the extent of characteristics of the open auger performance. The results of theoretical analysis and application of similitude are as follows: 1. It is possible to predict the power efficiency by the following equation; ${\eta}_p={\frac{P_n}{P_g}}=({\frac{{\omega}_s}{{\omega}_a}}){\cdot}tan{\gamma}{\frac{mg}{(F_mcos{\alpha}+F_scos{\gamma})}}$ 2. The reasonable range of the revolutions per minute of the open auger was presented as follow to cover completely with less power ; $$\frac{4d(L_a-L_i){\cdot}V_w}{{\pi}(D_o^2-D_s^2){\cdot}r{\cdot}{\frac{{\omega}_s}{{\omega}_a}}{\cdot}tan{\gamma}}{{\leq_-}}{\omega}_a{{\leq_-}}({\frac{{\omega}_a}{{\omega}_s}}){\sqrt{\frac{g}{r}}}$$ 3. The velocity of soil conveying to the direction of the auger shaft may be calculated by the equation; $V_h=({\frac{{\omega}_s}{{\omega}_s}})V_a{\cdot}tan{\gamma}$ 4. The factor of RPM was more important than other factors on the power efficiency.

• The Korean Journal of Rheology
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• v.9 no.4
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• pp.163-173
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• 1997

Polystyrene/polycarbonate 조성이 약 50/50인 3종류의 Poly(carbonate-g-styrene) 공중합체의 동적 탄성율, E*($\omega$)와 동적 스트레인-광학계수 O*($\omega$)을 유리전이 영역부근의 여러온도에서 동시에 측정하여 연구하였다. 두 개의 공중합체는 각각의 스티렌 그라프트쇄 에 5, 10 wt%의 MAH를 함유하고 있다. 이들 공중합체의 E*($\omega$)와 O*($\omega$)완화거동과 그라 프트 공중합체의 상용성과 연관하여 비교 고찰하였다. 공중합체들의 E*($\omega$)는 전형적인 무 정형 고분자의 유리전이 완하거동을 보였으며 정성적인 차이를 발견할수 없었다. 그러나 고 강도의 단일 tan$\delta$분산의 저주파수 영역에 미세분산을 나타내, 공중합체는 2상으로 분리되 어 있음이 추정되엇다. 폴리스티렌 그라프트체에 무수 말레인산 함유량이 증가함에 따라, 저 주파수 영역의 미세피크가 $\alpha$주분산에 병합되어 성분 고분자간의 상호 형동성이 증가함을 알수 있었다. 3공중합체의 유사한 기계적 특성과는 달리, 광학적 완화 스펙트럼 O*($\omega$)는 정 성적으로 명확한 차이를 보여 공중합체들의 광학완화 거동이 명확히 다름을 나타냈다. 기계 적 특성보다는 광학적 특성이 공중합체내의 성분 고분자의 미세한 완하 거동에 훨씬 민감한 응답을나타냈다. 이러한 특성적인 공중합체의 O*($\omega$)차이를 공중합체의 조성단일 고분자 PS, PC의 O*($\omega$)의 가성성을 가정하여 모사하였다 모사에서 구한 광학적 부분 기여 파라메 터를 사용하여 공중합체의 상용성을 고찰하였다.