• 제목/요약/키워드: Byung-cheon Park

검색결과 166건 처리시간 0.021초

건축물 실내 CO2 농도 분포에 따른 콘크리트 탄산화 깊이 산정에 관한 연구 (Analytic Expectation of Carbonation Depth of Indoor Concrete According to CO2 Concentration)

  • 박동천;박근석;안재철;강병희
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 추계 학술논문 발표대회
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    • pp.231-233
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    • 2011
  • Carbon dioxide in atmosphere causes concrete carbonation which is the phenomenon, that is, the pH of concrete changes from 12-13 to 8.85-10. Even though the carbon dioxide concentration of indoor is higher than that of outdoor, the micro measurement has not carried out. The concentration of carbon dioxide was measured in three places. The data was used as boundary condition to FEM analysis for expectation of concrete carbonation depth. The affect of building finish materials to concrete carbonation was discussed.

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Thin-film passivation of the polymer EL device using parylene and its application to the passive matrix PELD system

  • Lee, Cheon-An;Jin, Sung-Hun;Jung, Keum-Dong;Lee, Jong-Duk;Park, Byung-Gook
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.669-672
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    • 2004
  • The thin-film passivation technology using the poly-para-xylylene (parylene) was applied to polymer electroluminescent devices. The fabricated device shows a good luminescent characteristic of maximum 11640 cd/$m^2$. The measured lifetime was reached up to 28 hours, which means the effectiveness of the passivation. Applying the parylene thin-film passivation technique, 10${\times}$10 passive matrix display system was implemented and obtained some still images.

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RF 전력 증폭기 메모리 효과의 효율적인 측정과 모델링 기법 (Effective Measurement and modeling of memory effects in Power Amplifier)

  • 김원호;황보훈;나완수;박천석;김병성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.261-264
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    • 2004
  • In this paper, we identify the memory effect of high power(125W) laterally diffused metal oxide-semiconductor(LDMOS) RF Power Amplifier(PA) by two tone IMD measurement. We measure two tone IMD by changing the tone spacing and the power level. Different asymmetric IMD is founded at different center frequency measurements. We propose the Tapped Delay Line-Neural Network(TDNN) technique as the modeling method of LDMOS PA based on two tone IMD data. TDNN's modeling accuracy is highly reasonable compared to the memoryless adaptive modeling method.

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Most Probable Number 방법을 이용하여 측정한 중랑천 하상토양의 혐기성 세균의 수와 수질과의 상관 관계

  • 박두현;김병홍;임시근;최영효
    • 한국미생물·생명공학회지
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    • 제24권3호
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    • pp.364-370
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    • 1996
  • Sediments collected from the Jungnang-cheon and its tributaries were used to enumerate anaerobic bacteria by most probable number (MPN) methods. A simple method was developed to detect ferrous ion in the culture fluid in order to count the number of iron ion reducers, and sulfate-reducing bacteria (SRB) and methanogens were detected by the presence of FeS precipitate in the culture or methane in the head space, respectively. The numbers of iron reducer was in the range of 10$^{7}$ - 10$^{8}$ /g in the sediment of the stream containing higher organic content than the tributaries. The sediments of tributaries were analyzed to contain iron reducers less than 10$^{7}$ cells/g. With one exception the numbers of SRB and methanogens were less than 10$^{3}$ cells/g in the sediment. From these results it is concluded that organics in the sediment support the growth of iron reducers, which out-compete SRB and methanogens.

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오버레이 멀티캐스트에서 멀티미디어 스트리밍 서비스를 위한 최적 속도 할당에 관한 연구 (A Study on the Optimal Rate Allocation Problem in Overlay Multimedia Multicasting)

  • 정지복;최병천;박종대;류호용
    • 한국경영과학회지
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    • 제36권2호
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    • pp.33-42
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    • 2011
  • Overlay multicasting has received a lot of attention as a core technology for multimedia streaming service. In this paper, we consider the discrete optimal rate allocation problem in multimedia overlay multicasting, which has been proposed by Akbari et al.[2]. The computational complexity of this problem is not known. Thus, we propose a special case which can be solved in polynomial time.

정상 영역의 등고선 재구성을 위한 극좌표계 선형보간 (Polar-coordinates Linear Interpolation for Map Contour Reconstruction at Summit Area)

  • 황동국;전병민;박천주
    • 한국콘텐츠학회논문지
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    • 제5권1호
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    • pp.127-134
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    • 2005
  • 본 연구에서는 등고선 영상의 정점근방에서 발생하는 끊김을 연결하기 위하여 극좌표계 선형 보간을 제안한다. 성능을 평가하기 위해 몇 가지의 그래픽 영상에 기존 방법과 제안 방법을 적용한 실험에서, MAE가 평균 1.940화소인 선분을 생성할 수 있었다. 특히 실제의 등고선 영상에 대해서는 1.240화소의 MAE로 기존 방법보다 우수한 것으로 나타났다. 또한 인접 등고선과 닮은 꼴의 등고선을 생성함으로써 자연스러운 등고선을 재구성하였다.

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An intelligent consultant for material handling euqipment selection and evaluation

  • Park, Yang-Byung;Cha, Kyung-Cheon
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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    • pp.79-90
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    • 1995
  • The material handling equipment selection, that is a key task in the material handling system design, is a complex, difficult task, and requires a massive technical knowledge and systematic analysis. It is invaluable to justify the selected equipment model by the performance evaluation before its actual implementation. This paper presents an intelligent knowledge-based expert system called "IMESE" created by authors, for the selection and evaluation of material handling equipment model suitable for movement and storage of materials in a manufacturing facility. The IMESE is consisted of four modules: a knowledge base to select an appropriate equipment type, a multiple criteria decision making procedure to choose the most favorable commercial model of the selected equipment type, a database to store the list of commercial models of equipment types with their specifications, and simulators to evaluate the performance of the equipment model. The whole process of IMESE is executed under VP-Expert expert system environment.vironment.

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순서 독립적인 셋업타임을 가진 동일작업의 병렬기계 배치스케줄링 (Parallel Machine Scheduling with Identical Jobs and Sequence-Independent Setup Times)

  • 최병천;박명주
    • 한국경영과학회지
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    • 제39권3호
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    • pp.83-91
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    • 2014
  • We consider the problem of scheduling identical jobs with sequence-independent setup times on parallel machines. The objective is to minimize total completion times. We present the pseudopolynomial-time algorithm for the case with a fixed number of machines and an efficient approximation algorithm for our problem with identical setup times, which is known to be NP-hard even for the two-machine case.

실리카흄과 금속비누를 이용한 구체방수재의 개발에 관한 연구 (A Study on the Development of Self Waterproof Agents Using Silica Fumes and Zinc Stearates)

  • 최훈;이상태;박상준;신병철;한천구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.102-107
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    • 1999
  • This study is to develop a self waterproof agent by varying the addition ratios of silica fumes and zinc stearates. As the experimental results, it shows a possibility to produce a high performance self waterproof agent which performs a better properties in workability, strength, waterproof, dry-shrinkage and cost, if it is manufactured with silica fumes to zinc steartes ratios of 1 : 2 and mixed 6kg per 1㎥ into concrete mixtures.

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