• Title/Summary/Keyword: Yoon Dong-ju

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The Effect of Sphingosine-1-Phosphate in Survival of Grafted Fat Tissues (Sphingosine-1-Phosphate (S1P)가 이식지방의 생존에 미치는 영향)

  • Yoon, Dong-Ju;Choi, Soo-Jong;Choi, Chi-Won;Nam, Su-Bong;Bae, Yong-Chan
    • Archives of Plastic Surgery
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    • v.37 no.6
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    • pp.726-731
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    • 2010
  • Purpose: Autologous fat grafting is a popular procedure for the correction of the soft tissue depression and deformity. But there are several issues required to be carefully considered in relation to this procedure, mainly about the unpredictability and the low survival rate of the grafted fat due to absorption and partial necrosis. Sphingosine-1-phosphate (S1P) is a lysophospholipid mediator that has been proposed to promote angiogenesis and to regulate the differentiation of adipose derived stromal cells (ASCs). In this study, we analyzed the viability of the grafted fat tissue mixed with S1P into each 12 nude mice (cann.cg-fox1nu/crlori) compared to the group of mice grafted fat tissue only. Methods: Human aspirated fat was grafted subcutaneously into the backs of 8-week-old nude mice with or without S1P. Eight weeks later, the grafted fat was harvested and the weight and volume were checked. The fat was stained with hematoxylin-eosin and 4',6-diamidino-2-phenylindole. Results: S1P group weighed significantly more than the control group (p=0.009), and the volume from the S1P group was considerably larger than that of the control group (p=0.004) either. In histological features, the surviving layer of the S1P group was thicker than the control group and microvasculature appeared to be prominent in the S1P group, especially in the outer layers. Conclusion: These findings suggest that S1P plays a vital role in the soft tissue augmentation, potentially providing a novel point of the control in adipose tissue for microfat graft.

Spectral Analysis of VCXO using the Test Jig (측정용 지그 시스템을 이용한 VCXO의 스펙트럼 분석 및 성능평가)

  • Kim, Seng-Woo;Bae, Dong-Ju;Yoon, Dal-Hwan;Heo, Jeong-Hwa;Kim, Ho-Kyun;Han, Jeong-Su;Lee, Sun-Ju
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.61-64
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    • 2005
  • 본 연구에서는 $5mm{\times}7mm$ 크기의 적층 세라믹 SMD(surface mounted device)형 PECL VCXO에 테스트지그를 이용하여 스펙트럼을 분석한다. 패키지에 PECL 칩을 장착 후 와이어결선(wire bonding)을 완료한 VCXO는 그 길이 및 패키지 내부의 패턴 등에 의하여 부유인덕턴스(stray inductance) 및 커패시턴스가 발생하고, 칩의 발진부 임피던스에 영향을 준다. 이에 칩이 패키지에 장착된 상태에서 발진부 입력임피던스 영향을 제거하고 안정한 발진기 측정을 통하여 발진기의 정확한 스펙트럼 분석 및 성능을 평가한다.

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Single-Phase Active Power Filter based on Digital Controller (디지털제어기를 기반으로 하는 단상 능동전력필터)

  • Bae, Byung-Yeol;Lee, Ji-Heon;Lee, Hye-Yeon;Ju, Young-Ah;Han, Byung-Moon;Park, Byung-Ju;Yoon, Dong-Chul
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.5
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    • pp.789-796
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    • 2008
  • This paper describes a single-phase active power filter based on a newly developed digital controller. The developed controller utilizes FFT(Fast Fourier Transform) algorithm to extract the reference signal from the load current, considering the phase-angle delay of each order of harmonics. Optimized technique was applied for whole control algorithm to implement the real-time operation of developed controller. The performance of developed controller for a single-phase active power filter was verified through computer simulations with PSCAD/EMTDC. The feasibility of hardware implementation was confirmed by building and testing a prototype. The developed digital controller for a single-phase active power filter can compensate the harmonic current generated by the power supply for digital equipment.

Development of One-seg using ISDB-T (ISDB-T를 이용한 원세그 개발)

  • Yoon, Dal-Hwan;Bae, Dong-Ju;Jeng, Ye-Heun;Ko, Hyun-Seok;Kang, Sun-Yeung;Ju, Hyeong-Jung;Choi, Seung-Young
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.151-152
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    • 2007
  • In this paper, we have developed the one-seg for the car type using an ISDB-T. The one is the territorial broadcasting method of Japan and we call it an one-seg.

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The CHP system efficiency (열병합발전시스템의 효율)

  • Lee, Song-Keun;Choi, Jun-Young;Jang, Gil-Soo;Mok, Hyung-Soo;Son, Sung-Yong;Yoon, Yong-Tae;Son, Kwang-M.;Hon, Jun-Hee
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.784-785
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    • 2007
  • 열병합발전시스템의 경제성은 배열을 회수하여 사용함으로써 전기를 생산함과 동시에 열을 사용하여 에너지의 효율을 높이는데 있다. 그렇지만 열과 전기의 사용이 동시에 이루어지지 않을 경우에는 열병합발전시스템의 장점이 사라지게 된다. 이 논문에서는 열병합발전시스템의 효율을 계산하는 방법을 제시하여 열병합발전시스템을 도입하는 단계에서 좀 더 체계적인 방법으로 분석할 수 있는 방법을 제시하였다.

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Photochemical Reactions of Saccharin-$\alpha$-Silylamine Systems. Desilylmethylation of $\alpha$-Silylamine via Single Electron Transfer Pathway

  • Ung Chan Yoon;Young Sim Koh;Hyun Jin Kim;Dong Yoon Jung;Dong Uk Kim;Sung Ju Cho;Sang Jin Lee
    • Bulletin of the Korean Chemical Society
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    • v.15 no.9
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    • pp.743-748
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    • 1994
  • Photochemical reactions of saccharin with tertiary amines were explored. Saccharin was found to undergo an acid-base reaction with N-trimethylsilylmethyl-N,N-diethyl amine to form N-trimethylsilylmethyl-N,N-diethyl ammonium saccharin salt which is in equilibrium with free saccharin and N-trimethylsilylmethyl-N,N-diethyl amine insolution. Photoreaction of N-trimethylsilylmethyl-N,N-diethyl ammonium saccharin in $CH_3OH\;or\;CH_3CN$ results in the generation of desilylmethylated product, N,N-diethyl ammonium saccharin mainly along with benzamide. Photoreaction of N-methylsaccharin with N-trimethylsilylmethyl-N,N-diethyl amine in $CH_3OH$ leads to the production of o-(N-methylcarbamoyl)-N-ethylbenzenesulfonamid e as the major product along with N-methylbenzamide as the minor product. On the other hand, photoreaction of N,N,N-triethyl ammonium saccharin, generated from saccharin and triethylamine, produces N-methylbenzamide as the exclusive product. These photoreactions are quenched by oxygen indicating that triplets of saccharin and N-methylsaccharin are the reactive excited states. Based on the consideration of the redox potentials of saccharin and N-trimethylsilylmethyl-N,N-diethyl amine, and the nature of photoproducts, pathways involving initial triplet state single electron transfer are proposed for photoreactions of the saccharins with the ${\alpha}$-silylamine.

Expected problems in the Production of Nationwide Seamless Map Using Heterogeneous Spatial Data - with Emphasis on Digital Maps (이질적인 공간 데이터의 통합을 위한 범 국가적 연속지도 구축 방안 - 수치지도를 중심으로)

  • Kim, Yoon-Hyoung;Jeong, Jang-Yoon;Kyoung, Min-Ju;Yom, Jae-Hong;Lee, Dong-Cheon
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2007.04a
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    • pp.311-315
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    • 2007
  • Since the first phase of NGIS (National Geographic Information System) project was launched in 1988, various types and spatial database has been produced and updated. With recent developments in the information technology, the application of spatial data has increased in amount as well as in the coverage of the area of interest. There is a need for production and management of a nationwide single continuous digital map. This paper looks into three problems of map edge matching when dealing with such a task : 1) different scales of adjacent maps, 2) different time of capture between adjacent maps, and 3) different responsible organization where map matching has not been peformed along the boundary.

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A Study on Measurement Accuracy of Theodolite System(III) - A Measurement System Accuracy depending on a Distance of Scale Bar on the Distance 3 m between two Theodolites (데오드라이트 시스템의 측정 정확도에 대한 연구(III) - 시준거리 3 m에서 기준자 거리에 따른 측정 정도)

  • Yoon Yong Sik;Lee Dong Ju;Yoon In Jin
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.14 no.2
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    • pp.48-54
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    • 2005
  • The theodolite system consists of two theodolites, a scale bar and a target bu. A measurement accuracy of theodolite system is affected by a measurement distance of each equipment. This study was performed fir measuring an accuracy when the distance from theodolite to scale bar was changed 2~ 6 m on two theodolites distance 3 a The results showed thai the measurement accuracy could be $\pm$0.021 mm when the distance from theodolite to target was 2,3 and 6 n Specially, it was found that the maximum measurement accuracy was 10.017mm on theodolite collimation distance 3m and the distance 4 m of the theodolite and scale bar.

Performance Analysis of Maximum Data Rate for Telemetry Links in Space Communications for Lunar Explorations (달 탐사를 위한 우주통신에서 텔레메트리 링크에 대한 최대 전송속도 성능분석)

  • Lee, Woo-Ju;Yoon, Dong-Weon;Lee, Jae-Yoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.39 no.1
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    • pp.42-49
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    • 2011
  • Telemetry link requires high data rate to transmit the multimedia data for lunar explorations in space communications. In this paper, we analyze a data rate with the modulation and channel coding schemes based on Consultative Committee for Space Data Systems (CCSDS) in S, X, Ku and Ka bands, respectively. Then, we suggests modulation and channel coding schemes to meet the link margins and have a maximum data rate for lunar explorations in telemetry links.