• ALGAE
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• 제32권4호
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• pp.359-377
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• 2017

Pyropia haitanensis (T. J. Chang et B. F. Zheng) N. Kikuchi et M. Miyata is one of the most commercially useful macroalgae cultivated in southeastern China. In red algae, the biosynthesis of terpenoids through 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway can produce a direct influence on the synthesis of many biologically important metabolites. In this study, two genes of cDNAs, 1-deoxy-D-xylulose-5-phosphate synthase (DXS) and 1-deoxy-D-xylulose-5-phosphate reductase (DXR), which encoding the first two rate-limiting enzymes among MEP pathway were cloned from P. haitanensis. The cDNAs of P. haitanensis DXS (PhDXS) and DXR (PhDXR) both contained complete open reading frames encoding polypeptides of 764 and 426 amino acids residues, separately. The expression analysis showed that PhDXS was significant differently expressed between leafy thallus and conchocelis as PhDXR been non-significant. Additionally, expression of PhDXR and its downstream gene geranylgeranyl diphosphate synthase were both inhibited by fosmidomycin significantly. Meanwhile, we constructed types of phylogenetic trees through different algae and higher plants DXS and DXR encoding amino acid sequences, as a result we found tree clustering consequences basically in line with the "Cavalier-Smith endosymbiotic theory." Whereupon, we speculated that in red algae, there existed only complete MEP pathway to meet needs of terpenoids synthesis for themselves; Terpenoids synthesis of red algae derivatives through mevalonate pathway came from two or more times endosymbiosis of heterotrophic eukaryotic parasitifer. This study demonstrated that PhDXS and PhDXR could play significant roles in terpenoids biosynthesis at molecular levels. Meanwhile, as nuclear genes among MEP pathway, PhDXS and PhDXR could provide a new way of thinking to research the problem of chromalveolata biological evolution.

• Bulletin of the Korean Chemical Society
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• 제20권4호
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• pp.427-430
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• 1999

The Grignard coupling reaction of bis(chloromethyl)diorganosilanes [(ClCH2)2SiR1R2: R1 = R2 = Me, la; R1 = Me, R2 = Ph, lb; R1 = R2 = Ph, lc] with diorganodichlorosilanes [(Cl2SiR3R4: R3 = R4 = Me, 2a; R3 = Me, R4 = Ph, 2b; R3 = R4 = Ph, 2c] at THE reflux temperature gave the intermolecular C-Si coupling product of 1,1,3,3-tetraorgano-1,3-disilacyclobutanes 3a-f in poor to moderate yields ranging from 7% to 50% along with polydiorganosilapropanes. The cyclization reaction of la-c with methyl-substituted dichlorosilanes 2a, b gave 1,3-disilacyclobutanes 3a-c, e, d in moderate yields (42-50%), while the same reaction with dichlorodiphenylsilane (2c) to 1,3-disilacyclobutanes 3d, f resulted in low yield (7-18%) probably due to the steric hindrance of two-phenyl groups on the silicon of 2c.

• 자원리싸이클링
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• 제13권6호
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• pp.37-42
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• 2004

NiO, ZnO 조성이 다른 Ni-Cu-Zn 페라이트의 손실 분석을 실시했다. 손실, Ph는 측정 온도의 상승에 따라 감소해 100-120$^{\circ}C$ 근처에서 일정한 값을 얻었다. Pcv의 주파수의존성은 Pcv~f$^n$ 로 표현될 수 있는데, n은 1 MHz까지 일정했다. Pcv는 ZnO/NiO비가 증가함에 따라 감소한다. Pcv를 Hysteresis loss(Ph) 및 잔류손실(Pcv-Ph)로 분리했다. Pcv의 온도특성 및 조성 의존성은 Ph에 기인하지만, Pcv-Ph는 온도 및 조성에 의존하지 않는다. Ph와 초투자율, ${\mu}_i$의 온도 및 조성 의존성을 분석해, 다음과 같은 식이 성립된다는 것을 알 수 있었다. ${\mu}_i{\mu}_0=I_s^2/(K_I+b{\sigma}_0{\lambda}_s)$ Wh=13.5(I$_s^2/{\mu}_i{\mu}_0)$ 여기서, ${\mu}_0$은 진공의 투자율, I$_s$는 포화자화, K$_I$는 이방성상수, ${\sigma}_0$는 내부 불균일 응력, ${\lambda}_s$는 자기이방성 상수, b는 미지의 상수, Wh는 1주기 당의 히스테리시스 손실(Ph=Wh${\times}$f)이다. Ni-Cu-Zn 페라이트의 Steinmetz 상수 m=1.64~2.2는 Mn-Zn 페라이트보다는 적은데, 이는 양 재료 간의 손실 메커니즘의 차가 있음을 암시하는 것이다.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2004년도 13회 산화철워크샵
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• pp.3-11
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• 2004

NiO, ZnO 조성이 다른 Ni-Cu-Zn 페라이트의 손실 분석을 실시했다. 손실, Ph는 측정 온도의 상승에 따라 감소 해 $100-120^{\circ}C$ 근처에서 일정한 값을 얻었다. Pcv 의 주파수의존성은 $Pcv\~f^n$ 로 표현될 수 있는데, n는 1 MHz 까지 일정했다. Pcv 는 ZnO/NiO 비가 증가함에 따라 감소한다. Pcv 를 Hysteresis loss, Ph 및 잔류손실, (Pcv-Ph)로 분리했다. Pcv 의 온도특성 및 조성 의존성은 Ph에 기인하지만, (Pcv-Ph)는 온도 및 조성에 의존하지 않는다 Ph 와 초투자률, ${\mu}$i의 온도 및 조성 의존성을 분석 해, 다음과 같은 식이 성립된다는 것을 알 수 있었다. $${\mu}\;_i{\mu}\;_o=I_s\;^2/(K_1+b{\sigma}\;_o{\lambda}\;_s)\;\;\;\;(1)$$ $$Wh=13.5(I_s\;^2/{\mu}\;i{\mu}\;0)\;\;\;\;(2)$$ 여기서, ${\mu}\;_o$ 은 진공의 투자율, $I_s$, 는 포화자화, $K_1$는 이방성상수, ${\sigma}_\;o$는 내부 불균일 응력, ${\lambda}_\;s$ 는 자기이방성 상수,b는 미지의 정수, Wh는 1 주기 당의 히스테리시스 손실(Ph=Wh*f)이다. Ni-Cu-Zn 페라이트의 Steinmetz 정수 m=1.64-2.2는 Mn-Zn 페라이트보다는 적은데, 이는 양 재료간의 손실 메커니즘의 차가 있음을 암시하는 것이다.

• 영어어문교육
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• 제15권3호
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• pp.199-222
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• 2009

As great attention is given to a high quality of English education in Korea, more and more in-service and pre-service English teachers are looking for an opportunity to study in an English speaking country to become better qualified teachers. However, after receiving a degree in an English speaking country, many teachers fail to apply what they have learned to their own teaching due to their tensions of identity, beliefs, knowledge, and professionalism within the changes of sociocultural settings. By using sociocultural theory as a theoretical framework, this paper explores how formal training and Ph.D. studies in the U.S. have influenced a Korean teacher educator in applying theory to practice in relation to her identity, beliefs, knowledge, and professionalism during 30 years of her teaching experience. Rather than facing tensions, the teacher educator has been willing to change her roles, broaden and deepen her beliefs in teaching and knowledge about theory of teaching and learning, and continue her professional development. Limitations and implications of the study are provided.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.52.1-52
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• 2002

Young Sam Lee : He is currently a PhD candidate student. His research interest includes time-delay systems, signal processing, and receding horizon control. Wook Hyun Kwon : His research interest includes time-delay systems, signal processing, receding horizon control, and robust control. He is the president of IFAC 2008 which is to be held in Korea. Soo Hee Han : He is currently a PhD candidate student. His research interest includes time-delay systems, signal processing, receding horizon control, and communication.

• 대한본초학회지
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• 제30권3호
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• pp.69-76
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• 2015

Objectives : The effect of mixture extracted from Bupleuri Radix and Physalidis Herba(BR+RH) on the LPS-induced Depression in rats was investigated. Methods : Rats were administered intragastrically BR+PH after injectio of LPS to induce deprssion. Immobility was examined using Tail Suspension Test(TST), Forced Swimming Test(FST). The level of plasma corticosterone was measured by an Enzyme-Linked Immunosorbent Assay(ELISA) method. The expressions of c-Fos, Corticotropin Releasing Factor(CRF), NADPH-d in the Paraventricular nucleus(PVN) and TH in the Locus coeruleus(LC) were measured by immunohistochemical method. Results : In the effect of BR + PH on TST, immobility was significantly decreased comparing with the LPS group. In FST, immobility was shown decrease tendency in the BR+PH group. The expression of c-Fos in the PVN was significantly decreased at BR + PH400 group, comparing with the LPS group. The expression of CRF in PVN was shown dto have the decrease tendency in the BR+PH group, comparing with the LPS group. The expression of NADPH-d in PVN was not significantly decreased at BR+PH groups, comparing with the LPS group. The expression of TH in the LC was shown to have the decrease tendency at BR + RH groups, but not significantly, comparing with the LPS group. Conclusions : Anti-depressant effect of mixture after extracted from Bupleuri Radix and Physalidis Herba was through the anti-inflammatory effect via inhibition of HPA axis. NO and catecholamine system is not involved.

• Journal of international Conference on Electrical Machines and Systems
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• 제3권2호
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• pp.116-120
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• 2014

3-phase Induction machines are being used in industry and dq transformation from 3 phase of a, b, c is commonly used to analyze these machines. The equivalent circuits of d and q axis are however generally cross coupled and not simple to analyze. In this study, an analysis method of 3ph induction motor considering current regulator using dq transformation and matrix vector is proposed and it can explain the 3ph induction motor physically. This model does not need the separating process of d and q components. With this technique, the model becomes simple, is easy to understand in physical, and can get the same results with those from the other dq models. These simulation results of the proposed model are compared with those of other models for the conformation of the proposed method.

• Archives of Plastic Surgery
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• 제47권4호
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• pp.375-376
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• 2020

• 한국어류학회지
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• 제35권4호
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• pp.217-223
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• 2023

잔가시고기 Pungitius kaibarae의 신규 집단인 고령(GR) 집단과 야생 집단의 특성을 규명하기 위해 미토콘드리아 cytb 유전자 영역의 886 bp 서열을 이용 총 4개 집단 (경상북도 고령(회천, GR), 포항(곡강천, PH), 경산(오목천, GYSA), 강원도 고성(배봉천, GS))을 분석하였다. 고령(GR) 집단에서 가장 낮은 haplotype 다양성을 나타냈고(H_d=0.000), 고성(GS) 집단에서 0.755로 가장 높은 haplotype 다양성을 확인하였다. Nucleotide 다양성은 고성(GS) 집단에서 0.00291로 가장 높은 다양성을 나타냈으며, 고령(GR) 집단에서 가장 0.00000로 가장 낮은 다양성을 보였다. 유전적 분화도에서 고령(GR) 집단은 포항(PH) 집단과 유전적으로 가장 가까운 것으로 나타났다. Haplotype 네트워크는 고령 (GR) 집단이 포항(PH) 집단과 군집되어 가장 유사한 것으로 나타났다. 고령(GR) 집단은 계통발생학적 tree에서 높은 지지도(98%)의 값으로 포항(PH) 집단과 군집됨을 확인하였다. 따라서 고령(GR) 집단은 포항(PH) 집단과 유사한 집단에서 유래됨을 추정하였다.