• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.87-90
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• 2005

High-efficiency switched-mode circuits such as the class-E amplifier are well-known in the MHz frequency range. The class-E amplifier is a type of switching mode amplifier offering very high efficiency approaching 100%. In this paper of the class-E amplifier by using pHEMT device, the design has been done theoretically and experimentally, with simulation by using the harmonic balance method using circuit simulator. The amplifier using microstrip circuit and the pHEMT demonstrate 66% power-added- efficiency (PAE) at 2.4GHz with 17.6dBm of output power.

• Journal of the Korean Chemical Society
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• v.37 no.6
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• pp.618-625
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• 1993

Rate constants of hydrolysis of N-(benzoyl)-C-(N-methylanilino)imidoylchlorides were determined by UV spectrophotometry in 50% (v/v) aqueous methanol at 25$^{\circ}C$. On the basis of rate equation, substituent effect, solvent effect, salt effect, thermodynamic parameters and hydrolysis product analysis, it may be concluded that the hydrolysis of N-(benzoyl)-C-(N-methylanilino)imidoylchlorides proceed through $S_N$1 mechanism via azocarbonium ion intermediate in the range of from pH 3.0 to pH 10.0, while above pH 10.0 and below pH 3.0 the hydrolysis proceeds through nucleophilic addition-elimination (A$d_{N-E}$) mechanism.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.42-42
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• 2011

본 연구에서는 광학소자에 폭넓게 이용되는 AlGaP III-V족 화합물 반도체 중에서 한쪽 끝 이 종화합물인 AlP의 유전함수를 0.75~5.05 eV의 에너지 영역에서 타원편광분석법을 이용하여 분석하였다. AlP는 산소와 급격히 반응하기 때문에, 대기 중에서 물질 고유의 광특성이 유지되기 어려울 뿐만 아니라, 박막 위에 생성되는 산화막 때문에 순수한 AlP의 유전함수 측정이 불가능 하다. 본 연구에서는 물질의 유전함수에 미치는 산화 효과를 최소화하기 위하여 Molecular Beam Epitaxy로 성장한 $1.0{\mu}m$ 두께의 AlP 박막을 초고진공 상태의 chamber 안에서 타원편광분석기를 이용하여 실시간으로 측정하였다. 박막의 투명도에 의해 나타나는 간섭 pattern과 표면거칠기 효과로 인한 유전함수의 왜곡을 보정하기 위하여 변수화 모델이 이용되었으며 다층 변수화모델 계산을 통하여 순수한 AlP의 유전함수를 얻어낼 수 있었다. 본 연구에서 측정된 순수한 AlP의 유전함수는 타원편광분석기를 이용한 최초의 실험결과로서 이차미분을 이용한 전이점 (Critical Point) 분석결과 이론적인 electronic band structure에서 $E_1$, $E_1+_{{\Delta}_1}$, $E_2$에 해당하는 전이점들을 확인할 수 있었다.

• Journal of the Korean association of regional geographers
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• v.22 no.1
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• pp.86-101
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• 2016

La situation de la $r{\acute{e}}gion$ rurale et maritime de la province de Jeollanam-do en $Cor{\acute{e}}e$ du sud se $caract{\acute{e}}rise$ par une relative $p{\acute{e}}nurie$ de population. Le projet 'Ces ${\hat{I}}les$ que l'on aime visiter', $g{\acute{e}}r{\acute{e}}$ par la province de Jeollanam-do, s'articule autour de villages insulaires lieux de bien- ${\hat{e}}tre$ pour viser une augmentation de la population. Il s'agit de $d{\acute{e}}velopper$ le tourisme durable en s'appuyant sur la $beaut{\acute{e}}$ des paysages naturels, l'histoire, la culture et les traditions de cette $r{\acute{e}}gion$ insulaire. Pour cela, la participation active des habitants est essentielle. Cette ${\acute{e}}tude$ a pour but de $r{\acute{e}}fl{\acute{e}}chir$ aux moyens de $d{\acute{e}}velopper$ la participation des habitants en se fondant sur une $enqu{\hat{e}}te$ $men{\acute{e}}e$ dans la campagne. Nous avons mutuellement $analys{\acute{e}}$ entre les moyens de la participation des habitants et l'apanage $d{\acute{e}}mographique$ ${\grave{a}}$ cause de leurs $r{\acute{e}}sultats$ $diff{\acute{e}}rentes$. Voici les moyens de la participation des habitants $fond{\acute{e}}s$ sur la $caract{\acute{e}}ristique$ communautaire: $l^{\prime}activit{\acute{e}}$ $r{\acute{e}}mun{\acute{e}}ratrice$ communautaire; $l^{\prime}am{\acute{e}}lioration$ de l'habitat; les loisirs dans la $r{\acute{e}}gion$. Nous proposons plusieurs exemples pour $d{\acute{e}}velopper$ des programmes $fond{\acute{e}}s$ sur la participation des habitants de $l^{\prime}{\hat{i}}le$ de Nangdo, d'un rite communautaire maritime et des programmes ${\acute{e}}ducationnels$ d'explication touristique.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.807-811
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• 2007

Diabetes is marked by high glucose levels and is associated with decreased bone mass and increased fracture rates. To determine if [6]-gingerol could influence osteoblast dysfunction induced by 2-deoxy-D-ribose (dRib), osteoblastic MC3T3-E1 cells was treated with dRib and [6]-gingerol and markers of osteoblast function and oxidized protein were examined. [6]-Gingerol ($10^{-7}\;M$) significantly increased the growth of MC3T3-E1 cells in the presence of 30 mM dRib (p<0.05). [6]-Gingerol ($10^{-7}\;M$) caused a significant elevation of alkaline phosphatase (ALP) activity, collagen content, and osteocalcin secretion in the cells. We then examined the effect of [6]-gingerol on the production of osteoprotegerin and protein carbonyl in osteoblasts. Treatment with [6]-gingerol ($10^{-9}$ and $10^{-7}\;M$) increased osteoprotegerin secretion in osteoblastic cells. Moreover, [6]-gingerol ($10^{-9}$ and $10^{-7}\;M$) decreased protein carbonyl contents of osteoblastic MC3T3-E1 cells in the presence of 30 mM dRib. Taken together, these results demonstrate that [6]-gingerol inhibits dRib-induced damage and may be useful in the treatment of diabetes related bone diseases.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.1
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• pp.1-11
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• 2000

Relining and rebasing are essential for long-term success and oral health in removable prosthodontics. Major features of failures between metal base and relining resins are adhesive failure due to lack of chemical bonding. The purpose of this study was to find a better metal primer and metal surface treatment method that enhance the bonding strength with relining resin materials. The surfaces of ticonium alloys were treated with $25{\mu}m$ sandblasting (Group A), stone wheel(Group B), stone wheel and EZ oxisor(Group C), $75{\mu}m$ sandblasting(Group D) and EZ oxisor application after $75{\mu}m$ sandblasting(Group E). They were subdivided into no primer application (Group I), MR bond application(Group II) and Metafast bonding liner (Group III). Then specimens were completed though being bonded with relining resins. The specimens were stored in $38^{\circ}C$ water for 48 hours and tensile strength was measured using the universal testing machine. The results were as follows, 1. Primer application groups showed higher bond strength than no primer application group(p<0.05). 2. In comparison with primer application groups, MR bond group showed higher bond strength than Meta fast bonding liner application group(p<0.05). 3. In comparison with surface treatment methods, Bond strengths of group A and B were significantly different with group C, D, and E, and group C were significantly different with group D, and E in no primer application group()(0.05). In primer application groups, group A, B, C were significantly different with group D and E(p<0.05). According to results of this study, Metal primer application and metal surface roughening were considered to be advantageous for relining of metal base dentures.

• The Korean Journal of Mycology
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• v.22 no.3
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• pp.254-259
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• 1994

The ever increasing demand for energy and the shortage of resources all over the world have generated interest in recycling renewable sources such as lignocelluloses which otherwise would go to waste and cause environmental pollution. Lignin is the incrustation material for cellulose and hemicellulose, therefore, cellulose and hemicellulose are not easily degraded. Recycling lignocellulosic wastes as agricultural material are benefit to everybody and everything. In order to improve ligninase and laccase production of Phanerochaete chrysosporium, BKM-F-1767 and Ceriporiopsis subvermispora, FP 90031-SP, were compared. The ligninase activity of P. chrysosporium was maximum on day 4.5 of shaking culture at 150 rpm 2.5 cm in a back and forth cycle. The laccase activity of C. subvermispora was maximum on day 5.5 for 2% malt extract+0.1% yeast extract+0.1% Tween 20+6 mM Benzyl alcohol culture medium at stationary state.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.66-66
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• 2003

The aim of this study was to investigate effect of different energy substrates on embryonic development of mouse embryos. Two cell embryos, recovered from ICR female mice (4 weeks old) at 44~52hrs after hCG injection (mated just after hCG injection), were cultured fur 72 hrs in the medium (MEM) supplemented with the three different energy substrates [glucose(G), pyruvate(P) and lactate(L)] and combinations (Control: 0 mM: group A: G 0.5; B: G 3.15; C: P 0.1; D: P 0.32; E: L 5.87; F: L 10.5; G: G0.5+P0.32+L10.5; H: G3.15+P0.1+L5.87; I: G0.5+P0.1+L5.87; J: G3.15+P0.32+L10.5). Blastocysts were stained differentially using PI and bisbenzimide. The 69.8% of the 2 cell embryos cultured in group F were developed the blastocysts. This was the highest (NS) than all other tested groups (44.2~62.8%). Blastocysts, cultured in the group E (60.4$\pm$26.9) and G (58.1$\pm$26.3), had significantly(p<0.05: group E vs. control, B, C, D; G vs. control, A, B, C, D) higher mean cell number compared with the other (42.6$\pm$25.8 ~ 55.2$\pm$31.3) and control (42.6$\pm$25.8) was at the basal level. The proportion of ICM (% ICM of total cells) in blastocysts cultured in group B (26.0$\pm$9.5%), C (29.6$\pm$22.8%) and J (26.0$\pm$11.8%) were significantly higher (p<0.05: control vs. group B, C, J: A vs. C, J; C vs. D, E, I) than those of other tested groups (15.0$\pm$10.6 ~ 23.8$\pm$ 12.9％) and control (15.0$\pm$10.6％) was at the basal level. These results showed that energy substrates supported the development of mouse 2 cell embryos, especially with greater embryo development in high dose of lactate added to media.

• Korean Journal of Applied Biomechanics
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• v.14 no.2
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• pp.153-166
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• 2004

The purpose of this study was to investigate time of the phase, angle of the right ankle, knee, and hip joint, lateral angle of the trunk, mediolateral displacement of COM, and vertical displacement of COM between two groups while executing grand battement $jet{\acute{e}}$ $\acute{a}$ la seconde in a center exercise setting through 3D video analysis. The subjects participated in this study were skilled and unskilled 6 female ballet majors in Busan, respectively. The conclusions are as follows: 1. The time of the phase 2 was faster than P3. It shows a significant difference(p<.05) for P1 and P4 between skilled and unskilled groups 2. The angle of He right ankle joint has a significant difference(p<.05) at E4 between skilled and unskilled groups. The angle of the right knee joint has no significant difference at all events between skilled and unskilled groups. The angle of the right hip joint has a significant difference(p<.001) at E3 between skilled and unskilled groups. 3. The lateral angle of the trunk has a significant difference(p<.05) at E1 and at E5 between skilled and unskilled groups. The skilled group of the lateral angle of the trunk was lower than the unskilled group. However the skilled group's lateral angle of the trunk was bigger than the unskilled group at E3. It has significant difference(p<.001) at E3 between skilled and unskilled groups. 4. The mediolateral displacement of COM has no significant difference at all events between skilled and unskilled groups. The vertical displacement of COM has a significant difference(p<.01) at E3 between skilled and unskilled groups.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.207-215
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• 2012

Six different mashing types ((A) $koji$+purified enzyme, (B) $koji$+crude enzyme, (C) $koji$+$nuruk$, (D) $koji$+purified enzyme+$nuruk$, (E) $koji$+crude enzyme+$nuruk$, (F) purified enzyme+$nuruk$) had been established, according to fermentation agents and a mixing rate of rice $makgeolli$, in this study. The alcohol content was the highest in the mashing type (C), which was 13.6%, followed by (D) 13.5%, (A) 13.1%, (B) 12.9%, (E) 12.7% and (F) 12.1%. The reducing sugar content of (A) was the highest with 401.6 mg% and those of (B), (C), (D) and (F) were between 337.3- 380.9 mg%. The alcohol components were found and tended to increase during the fermentation. The oligo-saccharides content was the highest in (D) with 1251.3 mg%, which was followed by (E) 1,219.2 mg%, (C) 1,141.4 mg%, (A) 1,049.9 mg% and 973.8 mg% in (B). The total free amino acid was highest in (B) with 781.4 mg% and followed by (C) 703.2 mg%, (D) 702.6 mg%, (E) 678.7 mg%, (A) 630.4 mg% and (F) 328.7 mg% in order. There were 16 different types of volatile flavor components, in the mashing types (A) and (B), in addition to 15 different types of those in type (C), as well as 14 different types of those in (D), (E) and (F). There were significant differences in the overall preference between the type (A) and (C).