• Title/Summary/Keyword: Gwang Ju

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수열합성법으로 성장된 ZnO 박막의 열처리에 따른 특성 변화

  • Kim, Min-Su;Im, Gwang-Guk;Kim, So-ARam;Nam, Gi-Ung;Lee, Jae-Yong;No, Geun-Tae;Lee, Dong-Yul;Kim, Jin-Su;Kim, Jong-Su;Lee, Ju-In;Im, Jae-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.78-78
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    • 2011
  • 수열합성법을 이용하여 Si(111) 기판에 ZnO 박막을 성장하였다. ZnO 박막의 성장을 위한 씨앗층은 plasma-assisted molecular beam epitaxy (PA-MBE)를 이용하였다. 씨앗층의 표면 거칠기(root-mean-square roughness)는 2.5 nm이고, 씨앗층 위에 성장된 ZnO 박막은 다양한 크기의 입자들로 이루어져 있었으며 두께는 약 $1.8{\mu}m$로 매우 일정하였다. 배향성을 알아보기 위하여 texture coefficient (TC)를 계산해 보았다. TC(100)과 TC(200)은 a-축 배향성을, TC(002)는 c-축 배향성을 나타내는데, c-축으로 더 우세한 배향성(99.5%)을 보였다. TC 비율(TCa-axis/TCc-axis)은 열처리 온도를 $700^{\circ}C$까지 올렸을 때, 점차적으로 증가하였고, 그 이상의 열처리 온도(< $900^{\circ}C$)에서는 급격히 감소하였다. 잔류응력과 Zn와 O의 bond length도 유사한 경향을 보였다. $700^{\circ}C$까지 열처리 온도가 증가함에 따라, 잔류응력은 증가하였고 bond length는 감소하였다. Near-band-edge emission (NBE)의 피크 강도는 열처리 온도가 $700^{\circ}C$까지 증가함에 따라 점차적으로 증가하였다. 열처리 온도가 $800^{\circ}C$ 이상 증가함에 따라 deep-level emission (DLE)가 적색편이(red-shift)하였다. $700^{\circ}C$로 열처리를 한 ZnO 박막이 가장 우세한 (002)방향의 배향성을 보였을 뿐만 아니라 가장 큰 발광효율 증가를 보였다.

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광방사 세기비를 이용한 공정 플라즈마의 변수 진단

  • Lee, Yeong-Gwang;O, Se-Jin;Lee, Jae-Won;Hwang, Hye-Ju;Lee, Hui-Jin;Kim, Yu-Sin;Jeong, Jin-Uk
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.149-149
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    • 2011
  • 아르곤 기체의 방사세기 또는 그 세기 비는 플라즈마 공정 진단에서 일반적으로 사용된다. 본 실험에서는 100 mTorr 압력 조건하의 유도결합 플라즈마(13.56 MHz)에서 E-H 모드 전이 영역, rf 바이어스(12.5 MHz) 전력 인가 및 N2 혼합 시 단순화한 충돌-방사 모델에 기초한 광방사 세기비 방법을 적용하여 플라즈마 변수를 진단하였다. 개발 프로그램 기반의 분광기를 사용하여 아르곤 기체의 특정 파장(750.4, 751.5 그리고 811.5 nm)들을 관측하였고, 동일한 조건하에서 정전 탐침법으을 이용하여 전자 에너지 분포함수의 변화도 측정 하였다. 맥스웰 전자 에너지 분포를 가정하는 일반적인 경우와 비교하여 볼 때 실제적인 전자 에너지 분포함수의 측정은 전자의 가열 메커니즘에 대한 상세한 정보를 제공함과 동시에 플라즈마 재흡수에 대한 보정을 가능하게 해준다. 광방사 세기비법에 의해 측정된 결과에 의하면, 750.4 nm/751.5 nm는 높은 에너지(>13.08 eV)의 전자들의 유효 전자온도에 대한 정보를 나타내는 반면 811.5 nm/750.4 nm는 아르곤 준안정 준위 밀도(1s5)에 대한 정보를 제공하게 된다. 수행된 실험 조건하에서, 측정된 준안정 준위 밀도는 E-H 모드 전이 영역에서 최대값을 나타내었고 바이어스 전압 및 N2 기체 혼합 비율이 증가함에 따라 감소하는 결과를 얻었다. 유효 전자온도의 경우 광방사 세기비법과 정전 탐침법 모두 같은 결과를 보여 주었는데, E-H 모드 전이 영역에서는 전자온도는 거의 일정하였고 바이어스 전압 및 N2 기체 혼합 비율이 증가함에 따라 전자온도는 증가하였다. 이러한 실험 결과는 방전 모드 전이, 바이어스 인가 그리고 혼합 기체 사용하는 공정 플라즈마를 이해하는데 있어 이들 변수의 진단이 중요한 요소임을 보여준다.

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Manufacturing and Properties of CGI-based Composite Coating Layer Utilizing a Warm Spray Process and Cu-Ga and Cu-In Mixed Powders (Warm Spray 공정과 Cu-Ga 및 Cu-In 혼합 분말을 이용한 CGI계 복합 코팅층의 제조 및 특성)

  • Jeon, Min-Gwang;Lee, Myeong-Ju;Kim, Hyeong-Jun;Lee, Kee-Ahn
    • Journal of Powder Materials
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    • v.21 no.3
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    • pp.229-234
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    • 2014
  • This study manufactured a CIG-based composite coating layer utilizing a new warm spray process, and a mixed powder of Cu-20at.%Ga and Cu-20at.%In. In order to obtain the mixed powder with desired composition, the Cu-20at.%Ga and Cu-20at.%In powders were mixed with a 7:1 ratio. The mixed powder had an average particle size of $35.4{\mu}m$. Through the utilization of a warm spray process, a CIG-based composite coating layer of $180{\mu}m$ thickness could be manufactured on a pure Al matrix. To analyze the microstructure and phase, the warm sprayed coating layer underwent XRD, SEM/EDS and EMPA analyses. In addition, to improve the physical properties of the coating layer, an annealing heat treatment was conducted at temperatures of $200^{\circ}C$, $400^{\circ}C$ and $600^{\circ}C$ for 1 hour each. The microstructure analysis identified ${\alpha}$-Cu, $Cu_4In$ and $Cu_3Ga$ phases in the early mixed powder, while $Cu_4In$ disappeared, and additional $Cu_9In_4$ and $Cu_9Ga_4$ phases were identified in the warm sprayed coating layer. Porosity after annealing heat treatment reduced from 0.75% (warm sprayed coating layer) to 0.6% (after $600^{\circ}C/1hr$. heat treatment), and hardness reduced from 288 Hv to 190 Hv. No significant phase changes were found after annealing heat treatment.

Water Quality Forecasting of River using Neural Network and Fuzzy Algorithm (신경망과 퍼지 알고리즘을 이용한 하천 수질예측)

  • Rhee, Kyoung-Hoon;Kang, Il-Hwan;Moon, Byoung-Seok;Park, Jin-Geum
    • Journal of Environmental Impact Assessment
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    • v.14 no.2
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    • pp.55-62
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    • 2005
  • This study applied the Neural Network and Fuzzy theory to show water-purity control and preventive measure in water quality forecasting of the future river. This study picked out NAJU and HAMPYUNG as the subject of investigation and used monthly the water quality and the outflow data of KWANGJU2, NAJU, YOUNGSANNPO and HAMPYUNG from 1995 to 1999 to forecast BOD, COD, T-N, T-P water density. The datum from 1995 to 1999 are used for study and that of 2000 are used for verification. To develop model of water quality forecasting, firstly, this research formed Neural Network model and divided Neural Network model into two case - the case of considering lag and not considering. And this study selected optimal Neural Network model through changing the number of hidden layer based on input layer(n) from n to 3n. Through forecasting result, the case without considering lag showed more precise simulated result. Accordingly, this study intended to compare, analyse that Fuzzy model using the method without considering lag with Neural Network model. As a result, this study found that the model without considering lag in Neural Network Network shows the most excellent outcome. Thus this study examined a forecasting accuracy, analyzed result and verified propriety through appling the method of water quality forecasting using Neural Network and Fuzzy Algorithms to the actual case.

A Study on clothing in Suhainmyuldo painted on an old tomb of ancient kingdom of Goguryeo between the $4^{th}$ and late $6^{th}$ century

  • Kang, Eun-Sook
    • Journal of Fashion Business
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    • v.10 no.3
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    • pp.54-68
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    • 2006
  • Suhainmyuldo (樹下人物圖) is a type of picture which expresses a person under the tree and is known to be brought to the Korean Peninsula from the Middle Asia. The origin of this kind of expression is assumed to be from Iykshini (or Iygsha), the fairy of tree, in India and the 'Tree of Life' in Western Asia which influenced on the craft art design of Chinese art. However, Chinese art had already developed the motif of this kind in its unique way; for example, Jookrimchilhundo (竹林七賢圖: seven wise men in bamboo forest) in the Six Dynasty. There are only two items of female dress and its ornament from the 4th to 6th century Suhainmyuldo of the Goguryeo ancient tomb mural: one from the Jangchun Tomb No. 1 in which a female figure is portrayed as a part of living genre painting and the other from the Anahk Tomb No. 1 with seven female figures in a painting which is one of the earliest Suhainmyuldos, presumably from the 4th century. These two paintings must be considered in parallel with the origin of Suhainmyuldo. The mountain wizard's dress and Men's dress and its ornament in Suhainmyuldo from the 4th to the late 6th century Goguryeo ancient tomb is mostly joint adjust in which its collar is connected by a line and almost all the wizards are wearing Sang (upper garment). Most mountain wizards are wearing black feather shaped jackets and upper garments. One noticeable observation is that the mountain wizards of Mooyongchong, Tongu Ohgoibun Nos. 4 and 5 are completely different from one another in terms of ways to dress each wizard's official hats and shoes.

A Case Study on the Modernization of Traditional Brands, 'Burberry Prosum' - Focused on the Design Comparison between Original Burberry and Burberry Prosum - ('버버리 프로섬'의 사례를 통해 본 전통 브랜드의 현대화 연구 - 오리지널 버버리와 버버리 프로섬의 디자인 비교를 중심으로 -)

  • Jung, Kyung-Hee;Kim, Eun-Sil;Bae, Soo-Jeong
    • Journal of Fashion Business
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    • v.13 no.2
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    • pp.87-99
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    • 2009
  • The purpose of this study is to analyse the successful modernization strategy, and the difference between original Burberry and Burberry Prosum design. This will help in providing the fundamental information to Korean luxury fashion brands. Burberry, in particular, is rated as the most popular luxury brand in Korean fashion market. This brand has also rated 5th in sale worldwide and 1st in Korea in 2002, and was continuously been rated in 10th for the last 5 years. Related articles, fashion magazines, fashion web-site were used in this analysis, and the method was theoretical and case study. The results are divided into two categories of internal and external factors and two design patterns of check pattern and trench coat were observed. First of all, internal factor in Burberry is that they have scouted a new CEO and quickly changed their image with famous British models for the purpose of marketing strategies. They have also moved their main shop in London to Bond street, and opened shops in every country's capital cities. They were successful in achieving this by using celebrity marketing strategies with many famous celebrities. Secondly, external factor was that they have hired a designer named Christoper Bailey and this highlighted and enhanced the check pattern and trench coat. As a results, more generalized and diverse design items were presented and accessory line was enhanced, creating a much more younger image. This in turn attracted more younger customers. To sum up, original Burberry focused on classic designs, however Burberry Prosum focused on transforming traditional Burberry design into avant-garde and young. In other words, the reason for the success of this brand is highly dependent on its marketing strategies in which its uniqueness of schizophrenic cloche has appropriately represented and used in design.

Determining Relative Weights of Criteria for Evaluating National Quarantine Station by the Analytic Hierarchy Process (AHP방법(方法)을 적용(適用)한 국립검역소(國立檢疫所) 평가준거(評價準據)의 가중치(加重値) 결정(決定))

  • Yong, Yeong-Mun;Lee, Moo-Sik;Na, Baeg-Ju;Kim, Cheol-Ung;Kim, Gwang-Hwan;Yoo, In-Sook
    • Proceedings of the KAIS Fall Conference
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    • 2009.05a
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    • pp.817-820
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    • 2009
  • 신종 및 재출현 전염병이 지속적으로 유행하고 해외 전염병의 국내유입가능성이 증대됨에 따라 국립검역소의 검역관리 사업의 효율성 평가는 매우 중요하다. 연구는 평가 구성요소 사이의 상대적 중요도, 즉 가중치(weight) 부여에 있어서 과학적 타당성을 인정받고 있는 계층분석절차(Analytical Hierarchy Process; AHP) 기법에 의한 이원비교방법을 사용하여 설정하였다. AHP기법은 복잡한 다기준 의사결정문제(multi-criteria decision making problem)를 계층화하여 단순화 체계화시킴으로써 그 영향도를 계량화하는데 탁월한 기법이라는 평가를 받고 있다. 실제 측정에 있어서는 본 모형을 이용하여 얻어졌다. 대영역(기관평가영역, 서비스 및 프로그램평가 영역), 중영역(투입, 과정, 결과, 검역업무, 검사업무, 위생관리업무, 병원체조사감시업무, 전염병예방홍보 교육업무)으로 구분하여 최종적으로 평가지표로 선정된 지표는 실제 국립검역소 사업에 적용하였으며, 이에 대한 최소한의 평가지표를 최종 선정하여 향후 국립검역소사업 평가체계를 보다 체계화 하였다.

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Implementation of Acoustic Properties Measurement System Based on LabVIEW Using PXI for Marine Sediment (PXI를 이용한 LabVIEW기반 해양퇴적물의 음향특성 측정시스템 개발)

  • Park, Ki-Ju;Kim, Dae-Choul;Lee, Gwang-Soo;Bae, Sung Ho;Kim, Gil Young
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.3
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    • pp.216-222
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    • 2015
  • A previous velocity measurement system for marine sediment had several problems such as the errors occurred when picking first arrival time and the inconvenient measurement procedure. In order to resolve these problems, we developed a new acoustic properties measurement system by using PXI (PCI eXtentions for Instrumentation) module based on LabVIEW. To verify the new system, we measured the velocity and attenuation of sediment using the new system in a parallel with the previous system under the same experimental environment. The result of measurement showed 1~2% margin of error for the velocity as well as similar attenuation values. We concluded that the new system can efficiently measure the acoustic properties of marine sediment. It also has an advantage to construct the database of acoustic data and raw signal.

The Law Regarding International Marriage Migrant Women from the Perspective of Human Rights and Social Integration (인권과 사회통합관점에서 본 여성결혼이민자 관련법)

  • Wee, In-Baek
    • The Journal of the Korea Contents Association
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    • v.11 no.5
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    • pp.317-327
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    • 2011
  • This study examined with a view to legal system how to get over the adaptation problem as well as protection of human right about the cases of marriage immigration have sharply increased in Korea through Globalization and this brought about serious matters to multi-cultural families : disguise marriage, contract marriage, frequent divorces, especially conflict, violence, maltreatment of couple is guaranteed efficiently include against mankind universal value regardless of race, class, region undergoing farm village female marriage immigrants by cultural difference. This study is when the families of the marriage immigrants are left unattended in the state of the crisis, it definitely seems to be a serious obstacle for social integration and cost vast social expense. Therefore, I suggest the problems of multi-culture family support law and improvement plans for Marriage bureau agency management law and nationality Act through a comparative method about legislation of each country which has dealt with a phenomenon called 'multi-cultural Society' and fact-finding of female marriage immigrants in Gwang-ju Metropolitan City, professing "the city of human right".

Do Bars Trigger Activity in Galactic Nuclei?

  • Lee, Gwang-Ho;Woo, Jong-Hak;Lee, Myung-Gyoon;Hwang, Ho-Seong;Lee, Jong-Chul;Sohn, Ju-Bee;Lee, Jong-Hwan
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.75.1-75.1
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    • 2011
  • We investigate the connection between the presence of bars and AGN activity, using a volume-limited sample of ~6,000 late-type galaxies with axis ratio b/a > 0.6 and $M_r=-19.5+5logh$ at low redshift (0.02 < z ${\leq}$ 0.055), selected from Sloan Digital Sky Survey Data Release 7. Although bars are believed to play an important role in fueling AGNs, it is still an open question whether AGN activity is connected with the presence of bars. We find that the bar fraction in AGN-host galaxies (44.1%) is 2.5 times higher than in non-AGN galaxies (17.6%), implying an AGN-bar connection. However, this trend is simply caused by the fact that AGN-host galaxies are on average more massive and redder than non-AGN galaxies since the bar fraction increases with u-r color and velocity dispersion. When AGN-host and non-AGN galaxies with fixed u-r color and velocity dispersion are compared, the excess of bar fraction in AGN-host galaxies disappears. Among AGN-host galaxies we find no strong difference of the Eddington ratio distributions between barred and non-barred systems. These results indicate that AGN activity is not directly connected with the presence of bars.

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