• YAKHAK HOEJI
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• v.21 no.2
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• pp.81-86
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• 1977

A lignan glycoside, mp 263-$5^{\circ}$, $C_{34}H_{46}O_{18}$, was isolated from the cortex of Acanthopanax sessiliflorum forma chungbunensis C.S.Yook and it was identified as lirioresinol ${\beta}$-diglucoside, liriodendrin. The compound stimulated the incorporation of $^{14}$C-leucine into mouse liver protein.

• Korean Journal of Microbiology
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• v.29 no.4
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• pp.263-266
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• 1991

The growth of T. novellus in auto trophic and geterotrophic media was studied to determine the time required for cells to enter stationary phase and relative percentage of ribosomal proteins. When T. novellus was grown autotrophically, growth proceeded at a slow rate characteristic of autotrophs and did not enter log phase until the end of the first day. Logarithmic growth proceeded for 3-4 days at which time the cells entered the stationary phase. In particular, logarithmic growth was accompanied by decreasing pH of culture media and in the stationary phase the pH levelled off at 6.0, a decrease of 1.6 pH value compared to original pH of media. The pH decrease was greatest during log phase when cells oxidized thiosulfate to $H_{2}$$SO_{4}$. The doubling time was about 26h. In heterotrophic media growth proceeded at a much faster rate and cells entered stationary phase 20-22h after inoculation. The doubling time was 3h. The protein content of the ribosomes in T. novellus grown heterotrophically was 4.2% greater than those from the organism grown autotrophically.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.263-264
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• 2008

• Proceedings of the Korea Society for Simulation Conference
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• 1999.10a
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• pp.263-266
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• 1999

국제적으로 에너지관련 연구는 매우 비약적인 발전을 해가고 있다. 전기 에너지쪽을 살펴보면 발전소의 전기생산량은 호기당 나날이 늘어만 가고 있고, 이 호기당 전기 생산량은 터빈 또는 보일러의 금속의 재질의 한계성 때문에 열이나 압력등이 일정 수준이상으로 올라가기가 힘들다. 요즘은 이런 이유 때문에 단위기기 효율 향상이나 주변기기 효율 높혀서 궁극적으로 전체 효율을 높이는데 연구의 초점을 돌리고 있다. 발전소 Air Heater Auto Seal은 연소가스를 이용한 보일러내 연소용 공기의 온도를 높이는 장치이다. 발전소 효율의 중대한 영향을 미치는 A/H Sealing의 갭을 효과적으로 조정하여 발전소 효율을 극대화하는 방법에 관해 이론적 해석 및 시뮬레이션을 하고져 한다.

• Bulletin of the Korean Mathematical Society
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• v.56 no.1
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• pp.253-263
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• 2019

Let M be a curvature homogeneous or ball-homogeneous non-$coK{\ddot{a}}hler$ almost $coK{\ddot{a}}hler$ 3-manifold. In this paper, we prove that M is locally isometric to a unimodular Lie group if and only if the Reeb vector field ${\xi}$ is an eigenvector field of the Ricci operator. To extend this result, we prove that M is homogeneous if and only if it satisfies ${\nabla}_{\xi}h=2f{\phi}h$, $f{\in}{\mathbb{R}}$.

• The KIPS Transactions:PartB
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• v.9B no.3
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• pp.263-270
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• 2002

Most conventional systems of fire fighting control in a ship have been based on rule-based system in which expert knowledges are expressed with production rules. Renewing and adding of rules is needed continuously for the improvement of the system capability in an already build-up system and such adding and renewing procedures could hinder users from fluent utilization of a system. The author proposes an advanced fire fighting control intelligent system (A-FFIS) using rule-based and carte-based reasoning by clustering to implement conventional hybrid system (H-FFIS). Compared with H-FFIS, new approach with A-FFIS shows that the system proposed here improves fire detection rate and reduces fire detection time.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.556-562
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• 2005

This study was performed to evaluate effects of pH and heavy metals on soil pollution in 167 sites of Gangwon-do. The overall pH range of soils was 4.3~8.4 The average soil pollution of Cd was 0.089 mg/kg (0.000~3.493 mg/kg), Cu 3.093 mg/kg (0.078~60.263 mg/kg), Pb 4.74 mg/kg (0.01~38.08 mg/kg), Hg 0.054 mg/kg (0.002~1.050 mg/kg), and As 0.971 mg/kg (0.031~77.051 mg/kg), but $Cr^{6+}$ was not detected in these soils. The average concentration of heavy metals in these soils was acceptable under the preliminary standard of soil preservation acts in Korea.

• Broadcasting and Media Magazine
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• v.7 no.3
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• pp.83-93
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• 2002

본 고에서는 최근 표준화가 진행 중인 H.26L 부호기의 화면내 예측기법에 대해서 살펴보고자 한다 기존의 H.261, MPEG-1, MPEG-2등에서는 블록별로 독립적으로 UT 기반의 변환부호화를 수행하였으나, H.261의 화면내 부호화 방식은 공간 예측 및 정수형 변환을 사용한다. 또한, H.261에서 시작해서, MPEG-4에 이르기까지 지속적으로 사용되어 온 8x8화소 블록과는 달리 4x4또는 16x16단위의 처리, 휘도 성분과 색도 성분의 독립적인 처리 등 많은 새로운 부호화 방식이 도입되었다. 효과적인 예측 모드 부호화를 위해 주변 블록의 모드들을 이용한 예측 부호화 방식이 도입되었다. 기존의 가장 대표적인 화면내 부호화기인 H.263에 비해서 H.26L방식이 같은 화질에서 약40%의 추가적인 압축 효과가 있음을 확인하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.12C
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• pp.1209-1216
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• 2003

The transcoding is needed to modify the bit rate of the video bitstream in accordance with the bandwidth of a variety of channels in order to provide users with a realtime multimedia service and more stable and credible VOD(Video On Demand) service on various wire/wireless network. This paper suggests how to guarantee the video quality in the transcoding process, taking the activity and direction of the macroblock into consideration, thereby reducing the calculation. The threshold of the macroblock's activity and direction is applicable to the different videos, with the DCT coefficients from the intermediate data in the decoding process. Moreover, the suggested video transcoding algorism enables us to maintain the proper video quality and reduce the calculation through the video bit rate change experiment in H.263 environment.

• Journal of Broadcast Engineering
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• v.2 no.2
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• pp.194-205
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• 1997

In video compression standards such as MPEG and H.263. rate control is one of the key components for good coding performance. This paper presents a simple adaptive rate control scheme using a piecewise linear approximation model. While conventional buffer control approach is performed by adjusting the quantization parameter linearly according to the buffer fullness. the proposed approach uses a piecewise linear approximation model derived from logarithmic relation between the quantization parameter and bitrate in data compression. In addition. a forward analyzer performed in the spatial domain is used to improve image quality. Simulation results demonstrate that the proposed method provides better performance than the conventional one and reduces the fluctuation of the PSNR per frame while maintaining the quality of the reconstructed frames at a relatively stable level.