• Title/Summary/Keyword: Yun Dong-Ju

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The Development of Tool for Evaluating Quantitative Independency between FRs in Axiomatic Design (공리적 설계에서 FRs의 상호 독립성을 정량적으로 측정하기 위한 도구의 개발)

  • Kang, Young-Ju;Hwang, Yun-Dong;Cha, Sung-Woon;Jung, Dae-Jin;Moon, Yong-Rak
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.3
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    • pp.122-130
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    • 2001
  • Axiomatic Design is the useful tool for making a good design. In Axiomatic design, the independency is an important property to determine whether the design is good. Until now many designers decide the independency between FRs by their own decision. The way depending on inspiration is simple and fast, but it can not be considered as precise conclusion. Also there are not exact rule that evaluate the quantitative independency between FRs. This thesis will show the way to evaluated the quantitative independency of FRs from the comparison between FRs of more lower levels, and develop more efficient and objective tool in Axiomatic Design.

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Conductivity Change of PEDOT:PSS Film according to the Surface Structuring

  • Yu, Jung-Hoon;Nam, Sang-Hoon;Lee, Jin-Su;Hwang, Ki-Hwan;Seo, Hyeon-Jin;Ju, Dong-Woo;Jeon, So-Hyoun;Yun, Sang-Ho;Boo, Jin-Hyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.248.1-248.1
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    • 2014
  • We present results from an experimental study of conductivity change of poly (3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) film according to the surface structuring. We demonstrate that the patterned structure was enhanced with approximately five times conductivity in comparison with non structure of PEDOT:PSS film. In order to patterning, we have fabricated polystyrene (PS) colloidal monolayer as a template with sphere diameter of 780nm and 1.8um. Structure has honeycomb shape and it provide shorter path way to flowing of electron. Pattern size was controlled by PS diameter and varied by Transformer Coupled Plasma (TCP) etching system. Conductivity was converted from sheet resistance which measured by 4-point prove. Film thickness was derived using Field Emission Scanning Electron Microscopy (FE-SEM) images.

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친환경 CuInS2 나노입자가 고분자 박막층 안에 분산된 유기 쌍안정성 소자의 메모리 특성

  • Ju, Ang;Yun, Dong-Yeol;Kim, Tae-Hwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.393.1-393.1
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    • 2014
  • 유기물/무기물 나노복합체를 이용하여 제작한 유기비휘발성 메모리 소자는 간단한 공정과 플렉서블기기 응용 가능성 때문에 많은 연구가 진행되고 있다. 유기물/무기물 나노복합체를 사용하여 제작한 비휘발성 메모리 소자의 전기적 성질에 대한 연구는 많이 진행되었으나, Poly (N-vinylcarbazole) (PVK) 박막 내부에 분산된 친환경 CuInS2 (CIS) 나노입자를 이용하여 제작한 유기 쌍안정 소자의 메모리 특성에 대한 연구는 미미한 실정이다. 본 연구에서는 PVK박막층안에 분산된 CIS나노입자를 사용한 메모리 소자를 제작하여 전기적 특성에 대하여 연구하였다. 화학적으로 합성 된 CIS 나노입자를 톨루엔에 용해되어있는 PVK에 넣고 초음파 교반기를 사용하여 두 물질을 고르게 섞었다. 전극이 되는 indium-tin-oxide 가 성장된 유리 기판 위에CIS 나노입자와 PVK가 섞인 용액을 스핀코팅 한 후, 열을 가해 용매를 제거하여 CIS 나노입자가 PVK에 분산되어 있는 나노복합체 박막을 형성하였다. 형성된 나노복합체 박막 위에 상부 전극으로 Al을 열증착하여 비휘발성 메모리 소자를 제작하였다. 제작된 소자의 전류-전압 측정 결과는 메모리 특성을 나타내었으며, CIS 나노입자를 포함하지 않은 소자와의 비교를 통해 CIS나노입자가 비휘발성 메모리 소자에서 메모리 특성을 나타내게 하는 역할을 확인하였다. 전류-시간 측정 결과 소자의 ON/OFF 전류 비율이 시간에 따라 큰 변화 없이 1,000 회 이상 지속적으로 유지함을 관찰함으로써 소자의 전기적 기억 상태 안정성을 확인하였다.

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A Study on the Characteristics of Ammonia Doped Plasma Polymer Thin Film with a Controlled Plasma Power

  • Seo, Hyeon-Jin;Hwang, Gi-Hwan;Ju, Dong-U;Yu, Jeong-Hun;Lee, Jin-Su;Jeon, So-Hyeon;Nam, Sang-Hun;Yun, Sang-Ho;Bu, Jin-Hyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.242.2-242.2
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    • 2014
  • Plasma-polymer thin films (PPTF) have been deposited on a Si(100) wafer and glass under several conditions such as different RF power by using plasma-enhanced chemical vapor deposition (PECVD) system. Ethylcyclohexane, ammonia gas, hydrogen and argon were utilized as organic precursor, doping gas, bubbler gas and carrier gases, respectively. PPTFs were grown up with RF (ratio frequency using 13.56 MHz) powers in the range of 20~60 watt. PPTFs were characterized by FT-IR (Fourier Transform Infrared), FE-SEM (Scanning Electron Microscope), AFM (Atomic Force Microscope), Contact angle and Probe station. The result of FT-IR measurement showed that the PPTFs have high cross-link density nitrogen doping ratio was also changed with a RF power increasing. AFM and FE-SEM also showed that the PPTFs have smooth surface and thickness. Impedance analyzer was utilized for the measurements of C-V curves having different dielectric constant as RF power.

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온라인 전기 자동차를 위한 급전 및 집전 시스템

  • Jung, Gu-Ho;Lee, Kyung-Hun;Kim, Hyung-Guk;Cho, Yang-Jin;Song, Bo-Yun;Son, Young-Dong;Park, Eun-Ha;Choi, Ju-Young;Kong, Byung-O;Huh, Jin;Son, Ho-Sub;Cho, Jung-Gu;Rim, Chun-Taek;Jeon, Sung-Jeub
    • Proceedings of the KIPE Conference
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    • 2010.07a
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    • pp.218-219
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    • 2010
  • 온라인 전기자동차는 도로에 매설된 급전선로로부터 유도자계를 통하여 비접촉 방식으로 전기를 집전 받아 정차 및 주행 중에 충전하는 자동차이다. 이러한 비접촉 충전을 위해서는 도로에 매설된 급전 시스템과 차량 하부에 장착된 집전 시스템이 필요하며, 급전 시스템은 다시 급전 인버터와 급전선로로, 집전 시스템은 집전 모듈(pick-up)과 집전 레귤레이터로 구성된다. 본 논문에서는 급집전 시스템 각각의 장치를 소개하며, 더불어 구축된 시스템의 성능에 대해서도 소개한다.

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Design and Implementation of Field Classification and Information Retrieval Engine;JULSE (검색과 분류가 동시에 가능한 JULSE 시스템의 설계 및 구현)

  • Jang, Jeong-Hyo;Son, Ju-Sung;Kim, Do-Yun;Lee, Sang-Kon;Lee, Won-Hee;Ahn, Dong-Un
    • Proceedings of the Korea Information Processing Society Conference
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    • 2005.11a
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    • pp.673-676
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    • 2005
  • 기존의 정보검색 엔진은 문서의 분야에 상관없이 본문 전체의 내용을 보여주므로 사용자가 적합한 내용인지를 파악하기 위해서는 본문 전체를 읽어 보아야 그 적절성 여부를 알 수 있다. 본 논문에서 제안하는 방법은 질의어가 지시하는 분야를 분야연상어를 이용하여 자동으로 파악하고, 사용자가 원하는 분야에서의 검색이 이루어지도록 하는 검색과 분류가 동시에 가능한 엔진을 설계하여 검색결과의 성능을 향상하고자 한다. 이와 함께 적당한 분야연상어가 다수 출현한 단락을 사용자에게 제공하여 본문 전체를 보지 않아도 질의어에 적당한 문서인지를 빠르게 파악하도록 설계하여 구현하였다.

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Electrochemical Properties of Carbon Nano-tube as the Counter Electrode of Dye-sensitized solar cell (염료감응형 태양전지의 상대전극 재료로서 탄소나노튜브의 전기화학적 특성)

  • Kim, Hyun-Ju;Lee, Dong-Yun;Koo, Bo-Kun;Lee, Won-Jae;Song, Jae-Sung;Lee, Dae-Yeol
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.10
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    • pp.1090-1094
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    • 2004
  • Studies on porous oxide electrode, dye and electrolyte for dye-sensitized solar cells have been intensively carried out until now. However, counter electrode have not been much studied so far. Accordingly, it is needed to investigate new counter electrode materials with superior catalyst property and to substitute for Pt electrode. In this case, carbon nano-tubes (CNTs) are one of alternatives for counter electrodes as following merits: low resistivity, excellent electron emission property, large surface area and low cost due to development of mass production technique. Such advantages gave us to select multiwalled CNTs (MWCNT) as counter electrode for dye-sensitized solar cell. Also, cyclic voltammetry and impedance spectroscopy were used to investigate electrochemical properties of both CNT electrode and Pt electrode. It was found that sheet resistance of CNT electrode was similar to that of Pt electrode, also, electrochemical properties of CNT electrode was superior to that of Pt electrode on the basis on the measurement of CV and impedance spectrum. It was found that CNT is likely to be a very promising electrode material for dye solar cells.

Minimal-incision tenorrhaphy in flexor tendon injury (굴곡건 손상에서 최소절개 건 봉합술)

  • Jang, Ju Yun;Oh, Sang Ah;Kang, Dong Hee;Lee, Chi Ho
    • Archives of Plastic Surgery
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    • v.36 no.4
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    • pp.516-518
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    • 2009
  • Purpose: To retrieve the retracted flexor tendon, additional incision and wide dissection are conventionally required. We introduce minimal - incision tenorrhaphy using 1 cm - length incision and minimal dissection. Methods: Transverse incision about 1 cm - length is made over the level of retracted tendon. Nelaton's catheter is advanced into tendon sheath from distal primary laceration wound to emerge proximally through the incisional wound. Catheter is sutured to proximal tendon in end - to - end fashion. By gently pulling the catheter, retracted tendon is delivered to distal wound. Tenorrhaphy with core suture and epitendinous suture is then carried out. Results: This retrieving technique provides minimal incision, minimal dissection, minimal bleeding, minimal injury to tendon end, and shorter operation time with preservation of vincula tendinum and pulley system. Conclusion: In case of flexor tendon rupture with retraction, this operative method is believed to allow reliable and effective tenorrhaphy and excellent postoperative outcomes.

Anti-nociceptive Effects of Sorbus alnifolia (팥배나무의 진통 효과)

  • Kim, Bong Seok;Yun, Sun Hwa;Shin, Youn Chel;Kang, Bo Hye;Park, Seung Ju;Yang, Woo In;Lee, Se Youn;Cha, Dong Seok;Jeon, Hoon
    • Korean Journal of Pharmacognosy
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    • v.51 no.3
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    • pp.186-191
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    • 2020
  • In this study, we evaluated the anti-nociceptive activities of Sorbus alnifolia. To investigate the anti-nociceptive properties of the methanolic extract of Sorbus alnifolia (MSA), we conducted several tests using various experimental mouse pain models. Herein, MSA significantly delayed the latency time and writhing motion in the hotplate test and acetic acid test, respectively. These result indicated that MSA has an ability to manage both peripheral and central nociception. We could further confirm the analgesic effects of MSA by performing formalin test. In combination test using naloxone, a non-selective opioid receptor antagonist, analgesic activity of MSA was partly antagonized by naloxone, but not completely, indicating that the MSA acts as a partial opioid receptor agonist. Out results suggest that the S. alnifolia may be possibly used as valuable anti-nociceptive agent.

Four cases of gastric submucosal mass suspected as anisakiasis

  • KIM Seoung-Gu;JO Yun-Ju;PARK Young-Sook;KIM Sung-Hwan;SONG Moon-Hee;LEE Han-Hyo;KIM Jeong-Seon;RYOU Ji-Won;JOO Jong-Eun;KIM Dong-Hoon
    • Parasites, Hosts and Diseases
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    • v.44 no.1 s.137
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    • pp.81-86
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    • 2006
  • Anisakiasis is a parasitic disease caused by ingestion of raw fish infected with anisakid larvae. Endoscopic changing patterns of submucosal lesions in chronic gastric anisakiasis have not been known yet. Here we report 4 cases of suspected gastric anisakiasis which were improved during follow-up periods without surgical treatment. The patients presented with abdominal pain, nausea and vomiting after consuming raw marine fish, and visited our gastroenterology outpatient department. Their endoscopic findings showed firm and yellowish submucosal masses accompanied with eccentric erosions. Histologic findings showed severe eosinophilic infiltrations. In blood tests, peripheral eosinophil counts and total IgE levels were elevated. We believed that all cases were caused by larval anisakid infections. The submucosal mass lesions disappeared during the follow-up periods of 2 to 4 mo.