• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2018년도 춘계학술대회 논문집
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• pp.102-102
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• 2018

Electronic industry had required the finer size and the higher performance of the device. Therefore, 3-D die stacking technology such as TSV (through silicon via) and micro-bump had been used. Moreover, by the development of the 3-D die stacking technology, 3-D structure such as chip to chip (c2c) and chip to wafer (c2w) had become practicable. These technologies led to the appearance of HBM (high bandwidth memory). HBM was type of the memory, which is composed of several stacked layers of the memory chips. Each memory chips were connected by TSV and micro-bump. Thus, HBM had lower RC delay and higher performance of data processing than the conventional memory. Moreover, due to the development of the IT industry such as, AI (artificial intelligence), IOT (internet of things), and VR (virtual reality), the lower pitch size and the higher density were required to micro-electronics. Particularly, to obtain the fine pitch, some of the method such as copper pillar, nickel diffusion barrier, and tin-silver or tin-silver-copper based bump had been utillized. TCB (thermal compression bonding) and reflow process (thermal aging) were conventional method to bond between tin-silver or tin-silver-copper caps in the temperature range of 200 to 300 degrees. However, because of tin overflow which caused by higher operating temperature than melting point of Tin ($232^{\circ}C$), there would be the danger of bump bridge failure in fine-pitch bonding. Furthermore, regulating the phase of IMC (intermetallic compound) which was located between nickel diffusion barrier and bump, had a lot of problems. For example, an excess of kirkendall void which provides site of brittle fracture occurs at IMC layer after reflow process. The essential solution to reduce the difficulty of bump bonding process is copper to copper direct bonding below $300^{\circ}C$. In this study, in order to improve the problem of bump bonding process, copper to copper direct bonding was performed below $300^{\circ}C$. The driving force of bonding was the self-annealing properties of electrodeposited Cu with high defect density. The self-annealing property originated in high defect density and non-equilibrium grain boundaries at the triple junction. The electrodeposited Cu at high current density and low bath temperature was fabricated by electroplating on copper deposited silicon wafer. The copper-copper bonding experiments was conducted using thermal pressing machine. The condition of investigation such as thermal parameter and pressure parameter were varied to acquire proper bonded specimens. The bonded interface was characterized by SEM (scanning electron microscope) and OM (optical microscope). The density of grain boundary and defects were examined by TEM (transmission electron microscopy).

• 농업과학연구
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• 제26권1호
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• pp.50-57
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• 1999

본 시험은 L. monocytogenes KCTC 3443을 액체 배양한 후, 일반적인 열처리 및 마이크로파를 조사함으로써 가열효과에 의한 균의 불활성효과를 파악하는데 그 목적을 두었다. 2,450MHz, microwave oven을 통한 마이크로파의 온도 제어는 시료가 각각의 시험 설정 온도에 도달한 후 30분간 온도를 유지할 수 있도록 컴퓨터에 의해 제어되었으며, 온도의 편차는 ${\pm}1^{\circ}C$ 정도로 비교적 안정된 제어 효과를 보여주었다. 마이크로파 조사와 일반 가열처리 간의 균의 불활성효과를 비교한 시험에서는 55, 65, $75^{\circ}C$ 및 $85^{\circ}C$의 제어온도에서 거의 유사한 불활성도를 보여주었으며 이와같은 결과로 미루어 L. monocytogenes KCTC3443의 경우, 마이크로파 조사에 의한 비가 열 효과는 없는 것으로 보여진다. 아울러 공시균주인 L. monocytogenes KCTC3443는 $85^{\circ}C$의 30분간 가열에서도 약 $10^2{\sim}10^3cells/ml$의 균체가 생존하는 것으로 나타나 식품의 조리나 가열 후에도 2차 오염의 위험이 있는 병원성 균주로 주위가 요구된다.

• 한국식품조리과학회지
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• 제22권2호
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• pp.147-157
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• 2006

멥쌀가루의 특성을 개선하여 제빵을 비롯한 가공 적성을 증가하기 위해 습식제분쌀가루를 이용하여 수분함량을 30%와 50%로 조절하고, 50과 $70^{\circ}C$로 6시간과 18시간 열처리하여 수분-열처리 쌀가루를 제조하였다. 제조한 수분-열처리 쌀가루의 특성인 입도분포, 형태적, 이화학적특성과 호화특성을 건식제분과 습식제분 쌀가루와 비교하였다. 30% 수분함량으로 처리한 쌀가루입자는 습식제분쌀가루와 같이 $4-20{\mu}m$와 $100-200{\mu}m$ 범위에 분포하였으며 열처리온도가 증가하면 $200{\mu}m$이상의 입자가 형성되었다. 주사전자현미경으로 형태를 보면 30% 수분으로 처리한 경우에는 전분입자를 뚜렷하게 볼 수 있었으나 50%로 처리한 쌀가루는 쌀가루 입자끼리 엉겨 붙거나 호화된 상태를 보여주었다. 색도는 수분함량과 열처리온도가 높은 경우 명도는 감소하고 황색도는 증가하였으며 30% 수분함량으로 처리한 쌀가루의 물결합능력은 SWRF와 비슷하였다. $70^{\circ}C$에서 쌀가루의 팽윤력은 수분함량에 따른 차이는 없었으며 같은 수분함량에서 열처리 온도가 낮은 $50^{\circ}C$일 때 더 높았고 용해도는 더 낮았다. 신속점도 측정기에 의한 호화개시온도는 수분-열처리로 모두 높아졌으며 최고점도는 30%로 처리한 쌀가루가 높았고 setback은 30%로 $50^{\circ}C$에서 처리하였을 때 낮아 노화에 안정성을 보였다. 그러므로 수분함량을 30%로 조절하고 호화온도 이하의 온도인 $50^{\circ}C$로 처리한 수분-열처리 쌀가루의 특성이 쌀가루의 가공용으로 습식제분쌀가루보다 개선된 것으로 생각되었다.

• 한국작물학회지
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• 제24권1호
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• pp.107-118
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• 1979

1. 너도방동산이 (괴경), 올미 (괴경), 가래 (인경)을 공시해서 영양번식기관의 사멸온도 및 수분조건을 밝힘과 동시 사멸에 관여하는 양요인의 상호관계에 대하여 검토했다. 2. 저온처리에 의한 영양번식기관의 사멸양상은 초종간 차이가 보일뿐 아니라 토양건습에 의해 현저히 달라서 침수토양의 경우 영양번식기관의 저온치사한계는 너도방동산이가 -5^\circ C, 올마-7^\circ C 가래 -6^\circ C로 추정되었다. 이중 내동성은 올미가 가장 강하였다. 한편 건토에서는 초종의 내건성차이를 보여 0^\circ C 또는 -5^\circC가 되어도 너도방동산이와 올미의 괴경은 사멸하나 가래의 인경은 사멸되지 않았다. 3. 침수토, 건토 공히 괴경(인경)을 토양 표면과 상중2.5cm 깊이로 묻은 결과 침수토양에서는 양치상조건에서 사멸의 차이는 거의 없고 건토에서는 각 초종 모두 처리온도에 약간 차이가 있었다. 4. 괴경 (인경)의 고온치사한계에 있어서는 너도방동산이가 50^\circ C에서 2시간, 올미는 45^\circ C에서 24시간, 가래는 45^\circ C에서 1시간으로 사멸하는 것을 보여 고위도에 분포가 많은 가래가 고온에서 가장 약하였다. 5. 영양번식기관의 내건성에 있어서는 너도방동산이와 올미는 괴경수분이 40~50%에서 발아가 현저히 낮아지나 가래는 인경수분이 45%에서도 대부분 발아가 되어 건조에 강한 성질을 가지고 있었다. 6. 일광하에서 토양수분별 괴경치상위치와 발아와의 관계를 보면 가래는 토양수분이 3.5~4.5%인 건토(A Plot)에서 표면에 있거나 묻혀있는 경우 발아율이 낮아 고사하지만 토양성분이 17%이상인 경우에는 양치상 조건에서 고사되지 않았다. 그러나 너도방동산이, 올미는 토양수분17%에서 묻을 경우는 발아되지만 표면에 둘 경우는 토양수분25%에서도 2~3일 두면 발아능력을 상실하여 점차 고사하였다. 7 이상의 결과로서 경기에 의해 노출된 괴경의 사멸은 토양건습과 밀접한 관계가 있는 것으로 보이며 일반적으로 노출된 괴경은 동계 저온에 의한 것보다는 건조에 의한 사멸을 촉진하는 요인이 큰 것으로 보여 진다.

• 한국의류산업학회지
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• 제9권6호
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• pp.671-678
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• 2007

Formulations of compact and supercompact heavy-duty detergents, which are being used widely around the world, differ from those of conventional heavy-duty detergents. Significant differences in composition exist between the compact detergents and the conventional detergents. The compact detergents have a higher content of surfactants, oxygen bleach and enzymes than the conventional detergents. We have studied to find the most effective washing conditions of artificially soiled cloths with a commercial, supercompact, heavy-duty detergent and a drum type washing machine which is becoming the preferred type in Korea. Moreover, we have studied the washing performance with an impeller type washing machine, which has heretofore been the most popular type in East Asia. With the drum-type washing machine, washing performances improved as the washing temperatures went up and the washing times were lengthened. Though the rate of soil removal with a double recommended dosage was higher than with the recommended amount at $20^{\circ}C$, the effects of the higher dosage decreased as the washing temperatures increased. Finally, the washing performances with the two different dosages were the same at $60^{\circ}C$. The washing performances at $40^{\circ}C$ with the recommended dosage for 90 minutes were the same as with the double recommended dosage for 45 minutes. The soil removal efficiencies with the impeller-type washing machine were much lower than those of the drum-type washing machine. The reasons for this were the higher bath ratio that led to the lower concentration of wash liquor, the shorter washing time, and the lower washing temperature.

• 대한의생명과학회지
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• 제18권3호
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• pp.227-236
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• 2012

Previous study showed that swimming improved obesity but was not through $PPAR{\alpha}$ activation in liver and skeletal muscle in high fat diet-fed female mice with functioning ovaries as an animal model of obese premenopausal women. Thus, this study was aimed at investigation of the effects of swimming on the promotion of health and its molecular mechanism in adipose tissue of high fat diet-fed female mice. Eight-week-old female C57BL/6J mice were randomly divided into two groups (a non-swim control group and a swim group, n=8/group). Mice in the swim group swam for 2 h daily for 6 weeks in water bath with temperature of $35{\pm}1^{\circ}C$. All the animals received high fat diet (45% kcal fat) for 6 weeks. Reverse transcription-polymerase chain reaction was used to elucidate the molecular mechanism. Female mice subjected to swimming had significantly decreased body weight gain and white adipose tissue mass compared with the female control mice. Histological studies illustrated that swimming decreases the hepatic lipid accumulation. As expected, swimming did not affect the expression of mRNA levels of peroxisome proliferator-activated receptor (PPAR) ${\alpha}$ and $PPAR{\alpha}$ target genes responsible for mitochondrial fatty acid ${\beta}$-oxidation, such as carnitine palmitoyltransgerase-1 and medium chain acyl-CoA dehydrogenase in the white adipose tissue. However, mice that underwent 6-weeks of swimming exercise had decreased the mRNA expression of lipogenic genes, such as sterol regulatory element-binding proteins-1C and fatty acid synthase in comparison to sedentary control mice, with decreased $PPAR{\gamma}$ target genes involved in adipocyte-specific marker genes, such as adipocyte fatty acid binding protein and leptin in the white adipose tissue. These results suggest that swimming can effectively prevent obesity induced by high fat diet-fed, in part through down-regulation of adipogenesis and lipogenesis in white adipose tissue of female obese mice. Moreover, these results suggest that swimming maybe contributing the promotion of health through regulation of adipogenesis and lipogenesis in overweight premenopausal women.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.178-178
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• 2016

Every display is equipped with a cover glass to protect the underneath displaying devices from mechanical and environmental impact during its use. The strengthened glass such as Gorilla glass.$^{TM}$ has been exclusively adopted as a cover glass in many displays. Conventionally, the strengthened glass has been manufactured via ion-exchange process in wet salt bath at high temperature of around $500^{\circ}C$ for hours of treatment time. During ion-exchange process, Na ions with smaller diameter are substituted with larger-diameter K ions, resulting in high compressive stress in near-surface region and making the treated glass very resistant to scratch or impact during its use. In this study, PIIID (plasma immersion ion implantation and deposition) technique was used to implant metal ions into the glass surface for strengthening. In addition, due to the plasmonic effect of the implanted metal ions, the metal-ion implanted glass samples got colored. To implant metal ions, plasma immersion ion implantation technique combined with HiPIMS method was adopted. The HiPIMS pulse voltage of up to 1.4 kV was applied to the 3" magnetron sputtering targets (Cu, Ag, Au, Al). At the same time, the sample stage with glass samples was synchronously pulse-biased via -50 kV high voltage pulse modulator. The frequency and pulse width of 100 Hz and 15 usec, respectively, were used during metal ion implantation. In addition, nitrogen ions were implanted to study the strengthening effect of gas ion implantation. The mechanical and optical properties of implanted glass samples were investigated using micro-hardness tester and UV-Vis spectrometer. The implanted ion distribution and the chemical states along depth was studied with XPS (X-ray photo-electron spectroscopy). A cross-sectional TEM study was also conducted to investigate the nature of implanted metal ions. The ion-implanted glass samples showed increased hardness of ~1.5 times at short implantation times. However, with increasing the implantation time, the surface hardness was decreased due to the accumulation of implantation damage.

• 대한치과교정학회지
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• 제21권2호
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• pp.433-446
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• 1991

The present study was performed to evaluate the relaxation patterns of rubber elastics, elastomeric modules and chains stored in the water bath. Initial loading profiles were established for extension of $100\%,\;200\%$ of their original length for elastomeric chains and of 21, 28, 35, 42, 49mm for rubber elastics and elastomeric modules. The tests were performed on materials stored in distilled water at $37^{\circ}C$ and extraoral elastics stored in dry state at room temperature, at 0 hour, 1 hour, 6 hours, 1 day, 1 week, 2 weeks, 3 weeks, and 4 weeks, respectively. The following results were drawn: 1. The relaxation of rubber elastics manifested no correlation with increments of the extension distances, but showed correlation with time lapse. Remaining forces of rubber elastics carne out $84.6-98.52\%$ after 1 day, $70.92-89.31\%$ after 3 weeks of period. 2. The relaxation of elastomers manifested no correlation with increments of the extension distances, however represented considerable relaxation with time lapse as rapid relaxation after 1 hour and then gradual relaxations with time lapse. Modules relaxed much more than chains. $60.58-67.05\%$ of remaining forces for chains and $37.77-65.17\%$ for modules after 1 hour were turned out, and $51.48-62.22\%$ for chains and $8.04-25.15\%$ for modules after 3 weeks as well. 3. Permanent deformation rates of rubber elastics could not be measured with present investigation, but elastomers underwent severe deformations. 4. $3-9\%$ of permanent deformations for chains, $3-10\%$ for modules at 0 hour were turned out, and $25-30\%$ for chains, $96-145\%$ for modules after 3 weeks as well.

• Biomolecules & Therapeutics
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• 제1권2호
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• pp.211-219
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• 1993

The general and some pharmacological actions of DWP 302 were investigated in animals and the following results were obtained. In central nervous system, DWP 302 had no effects on the pentobarbital induced anaesthesia, locomotor activity, rotarod test, traction test, analgesic action in the mice and body temperature in the rat. DWP 302 showed no depressive action on the convulsion induced by strychnine and electronic shock. From these results, DWP 302 was considered to have no or little pharmacological effect on the central nervous system. Furthermore, DWP 302 had no influences on the normal blood pressure and heart rate. In the isolated ileum of guinea pig, DWP 302 showed neither contractive nor relaxing effects against the acetylcholine ($10^{-6}g/mι$), histamine ($10^{-6}g/mι$) and $BaCl_2$ ($10^{-4}g/mι$) at a concentration of $1.9{\times}10^{-4}g/mι$ in bath. But it caused a slight increase in basal tone at a concentration of $6.3{\times}10^{-4}g/mι$ and this effect was inhibited by atropine $10^{-7}g/mι.$ In the isolated trachea and vas deference, DWP 302 showed no effect on the contractions produced by histamine and norepinephrine, respectively. And DWP 302 showed no effect on the contractions produced by acetylcholine and oxytocin in the isolated nonpregnant rat uterus. DWP 302 had no effect on bile excretion, urine volume, pH and gastrointestinal motility, But, DWP 302 showed a significant inhibitory effect on gastric secretion in the rat.

• 한국염색가공학회지
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• 제20권2호
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• pp.75-82
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• 2008

The optimum extraction conditions of green tea used for a bath were investigated for application to textiles. The stability of the extracts and content of active ingredients were analyzed as well. The extraction was more effective in water and methanol than in ethanol. The optimum extraction temperature was determined as $80^{\circ}C$ in water and $60^{\circ}C$ in methanol. The solid extracts were obtained about 7% in water and 9% in methanol on the weight of dry green tea. The extracts were more stable in acid and neutral conditions than in alkaline region. From the analysis of contents of active ingredients, about 20% of effective catechins was appeared to be contained in the extract solid, which was thought to be available for application to textiles.