• Title/Summary/Keyword: Cheong Song

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Evaluation of Performance of Protective Surface Coating for Concrete

  • Ahn, Tae Song;Cheong, Hai Moon
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.1061-1066
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    • 2003
  • Chloride penetration into concrete is the main cause of the steel corrosion in concrete structures exposed to chloride-rich environments. Protective surface coatings are increasingly being applied to concrete structures to reduce chloride penetration. In this study, the performance of various surface coatings was evaluated. Most coatings showed good results for the various tests of the performance evaluation. Surface coatings can delay deterioration such as chloride-induced reinforcing bar corrosion effectively.

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A Programmable CMOS Negative Resistor using Bump Circuit (Bump 회로를 이용한 Programmable CMOS Negative Resistor)

  • Song, Han-Jung
    • Proceedings of the KIEE Conference
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    • 2002.11c
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    • pp.253-256
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    • 2002
  • A programmable CMOS negative resistor has been designed and fabricated in a 0.5um double poly double metal technology. The proposed CMOS negative resistor consists of a positive feedback OTA and a bump circuit with Gaussian-like I-V curve. Measurements of the fabricated chip confirm that the proposed CMOS resistor shows various negative resistance according to control voltage.

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Surface Chloride Content of Concrete in Domestic West and South Coast (국내 서남해안의 콘크리트 표면염화물량 산정에 관한 연구)

  • Cheong Haimoon;Ahn Tas-Song;Lee Byung-Duck
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05b
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    • pp.173-176
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    • 2005
  • Corrosion of reinforced concrete structures in marine environment is one of the most important mechanism of deterioration. For estimate of service-life for chloride attack, it is necessary to get exact surface chloride content. This paper reports the results of estimate for surface chloride content in domestic west and south coast.

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Optimizing the Cobalt Deposition Condition using the Experiment Design

  • Cheong, Seonghwee;Song, Ohsung
    • Proceedings of the Korean Magnestics Society Conference
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    • 2002.12a
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    • pp.184-185
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    • 2002
  • 최신 강자성 메모리 공정과 실리콘 비메모리 공정에서 Co, Ni, Fe 등 천이금속 계열의 증착 조건이 소자의 특성 향상 및 신뢰성 향상을 위하여 중요성이 점점 중요해 지고 있다. 강자성 메모리(MRAM)의 출현과 함께 Co, Ni, Fe 등의 수십 $\AA$ 두께를 전체 기판에 대해 균일하게 증착할 요구가 생겼다. MRAM에 요구되는 자기저항특성은 이러한 박막의 수 $\AA$ 두께 변화에 급격히 변화할 수 있으므로[1,2] 원하는 두께로 균일하게 증착 할 수 있는 기술의 확보가 필요하다[3]. (중략)

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실리콘 태양전지의 후면 점접촉 구조를 위한 Al 확산에 의한 국부 후면전계의 제조

  • Lee, Jun-Seong;Gwon, Sun-U;Song, Cheong-Ho;Park, Seong-Eun;Park, Ha-Yeong;Song, Ju-Yong;Park, Hyo-Min;Yun, Se-Wang;Kim, Dong-Hwan
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2009.05a
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    • pp.54.2-54.2
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    • 2009
  • 결정질 실리콘 태양전지의 알루미늄 후면전극이 패시베이션층의 공극을 통하여 확산됨으로써 국부 후면전계(local back surface field)가 형성되는 후면 점접촉 구조를 제조하였으며, 이에 대한 공정조건 및 특성을 연구하였다. 후면 패시베이션층은 실리콘 기판과 금속전극사이에 삽입됨으로써 표면 재결합속도를 낮추고, 후면 반사도를 높여 광흡수 경로를 증가시킬 수 있다. 고가의 사진식각기술 대신에 저가의 단순한 공정인 레이저 식각기술을 사용하여 후면 패시베이션층에 균일하고 잘 정렬된 공극 패턴을 형성할 수 있었다. 레이저 식각 조건 및 소성조건에 따른 Al 확산 국부 후면전계의 단면 형상을 주사전자현미경(SEM)을 사용하여 관찰하였으며 이에 대한 전기적, 광학적 특성 변화를 조사하였다.

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A Study on the Organization of the Village and the Characteristics of Folk Houses on Cheongunri in Cheong-Song (청송 청운리 마을구조와 민가특성 연구)

  • Kwak, Dong-Yeob
    • Journal of the Korean housing association
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    • v.19 no.2
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    • pp.105-114
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    • 2008
  • This study is conducted to investigate the organization of Cheongunri in Cheong-song, as well as the characteristics of folk houses. In this study, 82 folk houses, including the villages, are surveyed; among them, 15 houses are intensively analyzed in terms of the structure of plane and the arrangement of space. The focus of study is on discovering an internal order system of villages and tracing a relationship between the characteristics of houses and the environmental factors. According to the results of the study, an Intrinsic order in Cheongunri is found to be related to the mountain axis, the road system, and the flow axis; and the form of folk houses is also found to be influenced by this order. The major characteristics of folk houses can be summarized as follows: (1) Most of the houses face east along the mountain axis, whereas houses influenced by the flow axis tend to face south. (2) The side of houses tend to be open to the outside, showing external directionality. This characteristic seems to be closely related to the direction of the main gate in a house site. (3) The layout of the main quarters and the annex quarters is found to be related to the direction of the main gate in a house site. Especially, the characteristics of courtyard are found to be affected by the annex quarters. From the above results, it can be concluded that villages have an intrinsic order depending on the geographic characteristics of a surrounding natural environment, and folk houses have also changed accordingly.