• 정보와 통신
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• 제19권9호
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• pp.31-42
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• 2002

CRL (Communications Research Laboratory, Independent Administrative Institution, Japan) is developing ITS wireless communication technologies in millimeter-wave frequency region. Technologies are categorized for inter-vehicle communications (IVC) and road-vehicle communications (RVC). In this paper, system concepts and the experimental facilities are introduced. The experimental facility for inter-vehicle communications is gotten ready in 60 GHz frequency region and the experimental system for road-vehicle communications is based on RoF (Radio on Fiber) technology in 36-37GHz frequency region.

• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1433-1438
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• 2006

An AsFlFFF channel was designed and built, and then tested for analysis of pullulans and proteins. Pullulans and proteins having various nominal molecular weights were injected at various conditions of the cross-flow rate ($F_c$) and the channel-out flow rate ($F_{out}$). The retention (measured by the retention ratio R) and the zone broadening (measured by the plate height H) were measured, and then compared with theory. When the incoming flow rate, $f_{in}$ (and thus $F_{out}$) was varied with $F_c$ fixed at 2.5 mL/min, the plate height measured for the pullulan with nominal molecular weight (M) of about 100,000 showed the trend expected by the longitudinal diffusion theory (H decreases with increasing flow rate). In contrast, when $F_{out}$ was varied with the flow rate ratio, $F_c/F_{out}$, fixed constant at 5, the plate height measured for the same sample showed the trend expected from the non-equilibrium theory (H increases with increasing flow rate). Calibration plots (log D vs. log M) obtained with pullulans and proteins were not coincide, probably due to the difference in molecular conformation, suggesting the analysis of pullulans and proteins using AsFlFFF requires independent calibration. It was found that the linearity of the protein-calibration plot was improved by using a buffer solution as the carrier.

• Archives of Pharmacal Research
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• 제20권1호
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• pp.85-87
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• 1997

The activity-guided fractionation upon the MeOH extract of the aerial parts of Sorbaria sorbifolia var. stellipila led to the isolation of two cucurbitacin-compounds, cucurbitacin D and cucurbitacin F, as active principles. Two compounds were shown to exhibit significant cytotoxicity against cultured human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF-498, and HCT 15.

• 전자공학회논문지A
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• 제33A권7호
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• pp.149-155
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• 1996

A new technique wasdeveloped which obtains selectively the htick fully recessed oxidized porous silicon layer (OPSL) with good dielectric property. The porous silicon layer was ocnverted to thick fully recessed oxide (FRO) with 3-step (1${\mu}$m, 1.5${\mu}$m, 1.8${\mu}$m) by multi-step thermal oxidation (after 400$^{\circ}$C, 1 hour by dry oxidation, 700$^{\circ}$C, 1 hour and then 1100$^{\circ}$C, 1 hour by wet oxidation). The breakdwon field of the FRO was about 2.5MV/cm and the leakage current was several pA ~ 100 pA in the range of 0 of 90 pF. The progress of oxidation of a porous silicon layer was studied by examining the infrared abosrption spectra. The refractive index (1.51) of the fRO, which was measured by ellipsometer, was comparable to that of the thermally grown silicon dioxide (1.46). The etching rate (1600${\AA}$/min) of the FRO was also almost equal to that of the thermal oxide.

• Natural Product Sciences
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• 제24권1호
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• pp.54-58
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• 2018

A phytochemical investigation of Allium macrostemon Bunge (Liliaceae) afforded the new pregnane steroidal glycoside, named allimacroside F (1), along with three known glycosides, benzyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (2), phenylethyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (3), (Z)-3-hexenyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (4). The identification and structural elucidation of a new compound (1) was carried out based on spectral data analyses ($^1H-NMR$, $^{13}C-NMR$, $^1H-^1H$ COSY, HSQC, HMBC, and NOESY) and HR-FAB-MS.

• Journal of Applied Biological Chemistry
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• 제62권1호
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• pp.93-100
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• 2019

The root of Panax ginseng is used in ethnomedicine throughout eastern Asia and various recent studies have proved that Panax ginseng has inhibitory effects on cardiovascular disease. Each factor causing cardiovascular disease is known to have a very complex process which is achieved by a diverse number of mechanisms. Among these factors, platelets are the most important because they directly participate in thrombogenesis. Therefore, inhibiting the activity of platelets is an essential element for prevention of cardiovascular diseases. Our previous study showed the antiplatelet effects of Korean red ginseng extract and two of its components, ginsenoside Rg3 and ginsenoside Ro. However, the inhibitory mechanism of other ginsenosides remains unclear. Therefore, we investigated the inhibitory mechanism of ginsenoside F4 (G-F4) from Korean red ginseng on the regulation of signaling molecules involved in human platelet aggregation. With the use of G-F4, collagen-induced human platelet aggregation was inhibited in a dose-dependent manner, and it suppressed collagen-induced elevation of $[Ca^{2+}]_i$ mobilization through elevated phosphorylation of inositol 1, 4, 5-triphosphate receptor I ($Ser^{1756}$). In addition, G-F4 inhibited fibrinogen binding to ${\alpha}IIb/{\beta}_3$ during collagen-induced human platelet aggregation. Thus, in the present study, G-F4 showed an inhibitory effect on human platelet activation, suggesting its potential use as a new natural medicine for preventing platelet-mediated cardiovascular diseases.

• 대한전자공학회논문지SD
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• 제45권5호
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• pp.33-39
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• 2008

레이저 다이오드의 비선형성으로 인해 발생하는 왜곡성분들을 제거하기 위해 피드포워드 선형화 기법을 적용한 광송신기를 제작하였다. 레이저 다이오드의 파장차이에 따른 광전송 실험을 위해 광 주입 기술을 피드포워드 기법에 적용하여 3차 상호변조 왜곡성분(IMD3)의 크기변화를 측정하였다. 광 전송길이 및 레이저 다이오드의 파장차이로 인해 생기는 위상 부정합 현상을 분석하고 이에 따른 IMD3의 크기변화를 시뮬레이션 및 측정 하였다. 그리고 IMD3의 억제량의 변화를 극복하기 위해 정량적인 위상 가변량을 계산하였으며, 시스템 설계시 고려해야 할 가이드라인을 제시한다.

• Journal of Applied Biological Chemistry
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• 제65권4호
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• pp.253-259
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• 2022

본 연구의 목적은 서로 다른 지역에서 재배된 4년근 산양삼의 생육특성과 진세노사이드 함량 간의 상관관계를 조사하는 것이다. 유효 인산을 제외한 대부분의 토양 특성은 다른 재배지에서 보다 평창에서 유의적으로 높았다. 뿌리 길이와 세근수를 제외한 생육특성은 다른 재배지보다 평창 재배지에서 유의적으로 높게 나타났다. 8종의 진세노사이드 함량의 경우, 무주 재배지의 F2-AS 함량은 다른 재배지보다 높았으며, 영주 재배지의 F1 함량은 유의적으로 높게 나타났다. 영월 재배지에서는 Rb1과 Re-p의 함량이 유의적으로 높았고, 평창 재배지에서 Ro의 함량은 다른 재배지보다 유의적으로 높게 나타났다. 뿌리 길이와 토양 pH는 각각 토양특성 및 산양삼의 생육특성과 유의적인 상관관계를 보이지 않았다. 대부분의 생육특성은 전기전도도 및 유기물 함량, 전질소 함량, 치환성양이온(K⁺, Ca²⁺, Mg²⁺), 양이온치환용량과 유의적인 정의 상관관계를 보였다. Rb1과 Re-p는 세근수를 제외한 대부분의 산양삼 생육특성과 유의적인 부의 상관관계를 보였다. Ro는 줄기 길이, 줄기당 소엽수, 소엽 길이, 소엽 넓이, 뿌리 두께와 유의적인 정의 상관관계를 보였다. 본 연구의 이러한 결과는 4년근 산양삼의 생육특성과 진세노사이드 함량 간의 상관관계를 조사함으로써 품질 기준을 수립하기 위해 유용한 정보를 제공하는 데 도움이 될 수 있을 것이다.

• 한국생산제조학회지
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• 제22권5호
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• pp.824-830
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• 2013

In ultra-precision machining, the inside temperature should be controlled precisely. The important factors are environmental conditions (outside temperature, humidity) and temperature conditions (cutting heat, spindle heat). Thus, in this study, an environmental control cell for the ultra-precision machine that could control the inside temperature and minimize effects of the surrounding environment to achieve a thermal deformation of less than 400nm of a specimen was designed and verified through C.F.D. Further, a method that could control the temperature precisely by using a blower, heat exchanger and heater was evaluated. As a result, this study established a C.F.D technic for the environmental control cell, and the specimen temperature was controlled to be within $17.465{\pm}0.055^{\circ}C$.

• 생약학회지
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• 제31권1호
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• pp.87-94
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• 2000

Mt. Dae-Am is the branch-range of DMZ located on the $38^{\circ}7'$ N KangWon-Do in South Korea. The resources of important Herbal medicine (medicinal plants) were Phacellanthus tubiflorus (fam.: Orobanchaceae), Ostericum maximowiczii, Dendranthemum zawadskii Herbich f. latifolium, D. zawadskii subsp. acutilobum, D. var. campanulatum, Halenia corniculata (fam.: gentianaceae), Prunus mandshurica var. glabra, Acanthopanax divaricatus f. inermis. A. chiisanense, A. sessiliflorum, Eleutherococcus senticosus, Bupleurum longeradiatum, Heracleum moellendorffii sub-spp. subbipinnatum, Sanicula rubriflora, Spuriopimpinella bracycarpa f. latifolia, Angelico gigas, Artemisia montana, A. stelleriana, Paeonia japonica, Phellodendron amurense, Schizandra chinensis, Menyanthes trifoliata, and Gentiana axillariflora var. coreana, etc.