• 동의생리병리학회지
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• 제24권3호
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• pp.439-445
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• 2010

Pretreatment with Taraxacum Mongolicum H(TMH) prior to the administration of on $CCl_4$ significantly prevented the increased serum enzymatic activity of aminotransferase(ALT, AST), gamma-glutamyl transpeptidase(GGT) and bilirubin concentration in dose-dependent manner. In addition, pretreatment with TMH also significantly restored the elevation of hepatic malondialdehyde formation and the depletion of reduced glutathione content in the liver $CCl_4$-intoxicated rats. The restoration of microsomal aniline hydroxylase and aminopyrine N-demethylase activities indicated the improvement in functional status of endoplasmic reticulum. $CCl_4$-induced hepatotoxicity was also essentially prevented, as indicated by a liver histopathologic study. TMH showed antioxidant effects in $FeCl_2$-ascorbate-induced lipid peroxidation in rat liver homogenate and in superoxide radical scavenging activity. Our results suggest that the protective effect of TMH against $CCl_4$-induced hepatotoxicity possibly involve mechanisms related to its ability to block p450-mediated $CCl_4$ bioactivation and free radical scavenging effects.

• 방송공학회논문지
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• 제7권1호
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• pp.37-44
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• 2002

본 논문에서는 동영상을 효율적으로 부호화하기 위한 새로운 다중 해상도 움직임 보상방법과 잉여 양자화 방법을 제안한다. 본 논문에서 제안하는 동영상 부호화기는 다단계 웨이브렛 분해, 움직임 예측 및 움직임 보상. 대역내에서의 래스터 주사. 블록 Tree의 구성 및 블록 분할. 적응적 산술 부호화기로 구성된다. 제안된 동영상 부호화기는 단순하면서도 낮은 연산량을 필요로 하며. 임베디드 특성과 SNR 계위 부호화 특성과 같은 좋은 기능을 제공한다. 또한 기존에 제안되었던 웨이브렛 변환을 이용하는 동영상 부호화 방법과 비교하여 우수한 성능을 제공한다.

• 천문학회보
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• 제36권2호
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• pp.147.1-147.1
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• 2011

We investigate the chemical differentiation in F, G, K type stars with and without planets to extend the work by Kang et al. (2011) to various spectral types. Since the primordial chemical composition has been preserved in the stellar atmosphere, stellar metallicity can provide the information on the primordial material, which is the potential building block of planets. Therefore, we can explore the favored conditions for planet formation through the comparison of chemical compositions between planet-host stars (PHSs) and stars without planets. In this work, we analyze 19 F, G, and K type stars. In each spectrum, we measure equivalent widths (EWs) of Fe, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Co, and Ni using TAME (Tools for Automatic Measurement of Equivalent width). The abundances of these species can be derived with the measured EWs and MOOG code (Sneden 1973). Like results by precedent studies, we find that planet-host stars have abundances higher than stars without planets. The typical difference in the abundances of Na, Mn, Co and Ni is $0.4{\pm}0.2dex$. In addition, as found in Kang et al. (2011), Mn is the most different element between PHSs and comparison stars.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제14권3호
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• pp.228-236
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• 1992

This study was to designed to evaluate the reactions of mouse femoral bone to bone wax. In sixteen mice with a strain of I. C. R. mouse weighed approximately 300 to 850g 2.0~2.0mm sized bone defects were created by drilling. Half of mice were inserted by bone wax and the remainder serving as control without bone wax application. The mice were sacrificed 1, 2, 6, 8 weeks after operation and block specimens were prepared for light microscopy examination. The results obtained were as follows. 1. Histologic features of tissue reaction to bone wax were the presence of inflammatory cell infiltration and multinucleated giant cell. 2. Bone ear healing from the created margin were markedly impaired by the application of bone wax 3. New bone formation was markedly decreased in bone wax application.

• 한국주거학회논문집
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• 제18권2호
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• pp.105-112
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• 2007

This research has been implemented based on the area of #369 Dowon-dong, Dalseo-gu, Dae-gu which is considered as a place with satisfactory characteristics for the flow of fresh air into the city. Simulations of the target area both prior to the development plan and after apartment complex blocking were analyzed in regard to blocking planning and pilotis based on the main direction of wind, $90^{\circ}$ (east wind) and $180^{\circ}$ (south wind). In addition, congested wind corridor flow in the target place was identified through a pollution spread simulation according to the wind corridor. Therefore, the flow of wind in the one area is affected by the blocking of the complex and the main direction of the wind. Also blocking, in regard of pilotis, provides a better flow of wind. This study was implemented based on wind formation by apartment complex planning, so further study on the other factors affecting the flow of a wind corridor along with block planning and pilotis need to be carried out. Sustainable environmental factors through analysis of the environmental factors have to be analyzed. Moreover, building and complementing fundamental resources and systematic devices should be supported.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.52-55
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• 2000

Structually organized mono- and multilayers were developed on gold for the catalytic and affinity biosensing using hyper-branched dendrimers. For the catalytic biosensing interface, a new approach to construct a multilayered enzyme film on the electrode surface was developed. The film was prepared by layer-by-layer depositions of dendrimers and periodate-oxidized glucose oxidase. The voltammograms obtained from the GOx/dendrimer multilayered electrodes revealed that bioelectrocatalytic response is directly correlated to the number of deposited bilayers. From the analysis of voltammetric and ellipsometric signals, the coverage of active enzyme per layer during the layering steps was estimated, demonstrating the spatially-ordered multilayer formation. As an extension of the study, dendrimers having various degrees of ferrocenyl modification were prepared and used. The resulting electrodes were electrochemically characterized, and the density of ferrocenyl groups, active enzyme coverage, and sensitivity were estimated. For the affinity-sensing surrface, a biosensor system based on avidin-biotin interaction was developed. As the building block of affinity monolayer, G4 dendrimer having partial ferrocenyl-tethered surface groups was prepared and used. And the biotinylated and electroactive dendritic monolayer was used for the affinity-sensing surface interacting with avidin. Electrochemical characterization of the resulting biosensor was conducted using free enzyme in electrolyte in terms of degree of surface coverage with avidin and subsequent surface shielding.

• 한국위성정보통신학회논문지
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• 제9권2호
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• pp.12-17
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• 2014

본 논문에서는 고전압에서 동작하는 마이크로칩의 안정하고 튼튼한 정전기 보호 성능을 구현하기 위해 이중 극성 소오스를 갖는 DPS_EDNMOS 변형소자가 제안되었다. 제안된 DPS는 N+ 소오스로 부터 전자 풍부 영역이 측면 확산되는 것을 방지하기 위해 N+ 소오스 측에 P+ 확산층을 의도적으로 삽입한 구조이다. 시뮬레이션 결과에 의하면 삽입된 P+ 확산층은 고전자 주입에 의해 발생하는 깊은 전자채널의 형성을 효과적으로 막아주고 있음을 알 수 있었다. 따라서 종래의 EDNMOS 표준소자에서 문제시 되었던 더블 스냅백 현상을 해결할 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.514-514
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• 2007

1차원 구조를 갖는 나노 와이어들은 나노 소자를 구현하기 위한 building-block으로 많은 과학자들의 주목을 받고 있고 또한 연구되고 있다. 하지만 그것을 정확하게 위치시키고 일정한 간격으로 정렬시키기 위한 기술 개발은 아직도 해결해야 할 큰 과제로 남아 있다. 이 논문에서, 우리는 ahsing 기술과 표면 패터닝 기술을 이용하여 대면적의 실리콘웨이퍼 위에 DNA(deoxyribonucleic acid)를 기반으로 한 금 나노 와이어를 정확하게 위치시키고 일정한 간격으로 정렬시킬 수 있는 새로운 제어 기술을 제안한다. 먼저 우리는 포토 리소그래피 공정과 $O_2$ 플라즈마 ashing 기술을 이용하여 선폭을 100 nm로 감소 시켰다. 그리고 자기조립단분자막 (self-assembled monolayers; SAMs) 방법과 lift-off 공정을 반복함으로서 1-octadecyltrichlorosilane(OTS) 층과 aminopropylethoxysilane(APS) 층을 형성하였다. 마지막으로 DNA 용액을 샘플 표면 위에 도포하고 분자 빗질 방법으로 DNA를 한 방향으로 정렬 시켰고 금 나노입자 용액을 처리하였다. 그 결과 금 나노 와이어는 $10{\mu}m$ 간격으로 일정하게 정열 되었고, APS 층에만 정확하게 정렬되었다. 우리는 금 나노 와이어를 관찰하기 위하여 원자간력 현미경 (Atomic Force Microscope AFM)을 사용하였다.

• 대한원격탐사학회지
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• 제11권2호
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• pp.59-73
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• 1995

The study is focused on the analysis of geomorphological environment changes of alluvial bar in lower Kum river using satellite-based multitemporal/multisensor data. Landsat datas for environment changes analysis consists of Landset MSS(2 scenes) and Landset TM(7 scenes) acquired from 1979 to 1994. This study is to develop the analysis techniques for the environment change detection of using ratio, classification, false color composite etc, of Landsat data especially useful to the geomorphological study of tidal flats and river channels. The results of this study can be summarized as follows : 1. The lower Kum River alluvial bar have had rapid geomorphological changes after the construction of the temporary dam to block the river flowing in 1983. The most alluvial bar located in the river has both bankway growth, especially the allurival bar in the Lower Kum River had grown between 1983 to 1990. 2. After construction of the estuarine barrage, no remarkable geomorphological changes have been found in Kum River area but the growth and formation of new underwater bar has continued. The enormous materials was needed for the growth and formations of new underwater barrier oslands and bar would be supplied from the sea bottom and river sediment to diminish of stream velocity after construction of the estuarine barrage.

• 반도체디스플레이기술학회지
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• 제8권2호
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• pp.31-35
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• 2009

In the silicon wafer polishing process, the mounting stage of silicon wafer on the ceramic carrier block has been using the polishing template which utilizes the porous surface instead of traditional wax mounting method. Here in this article, the experimental study is carried out in order to study the wafer demounting by water jet and the effects of operating conditions such as the water jet flowrate and the number of water jet nozzles on the wafer demounting time. It is found that the measured wafer demounting time is inversely proportional to the water flowrate per nozzle, regardless of number of nozzles used; implying that the stagnation pressure by the water jet impingement is the dominant key factor. Additionally, by using the transparent disk instead of wafer, the air bubble formation and growth is observed under the disk, making the passage of water flow, and subsequently demounting the wafer from the porous pad.