• 제목/요약/키워드: Yoon Baek Nam

검색결과 153건 처리시간 0.031초

국내 저온용 집열기의 열성능 특성 (Thermal Characteristics of Domestic Solar Collector for Low-Temperature Applications)

  • 김정배;이순명;윤응상;이진국;주문창;이동원;곽희열;백남춘
    • 한국태양에너지학회 논문집
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    • 제27권3호
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    • pp.155-160
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    • 2007
  • This study shows the results on thermal performance test with domestic solar collector for low-temperature applications using KS, then reveals the efficiency difference between KS and EN standard. Using the test results, this study Presents the status of thermal performance with domestic solar collector including flat-plate, single evacuated, and double evacuated (with mirror or U-tube) solar collector.

Corrosion at the Grain Boundary and a Fluorine-Related Passivation Layer on Etched Al-Cu (1%) Alloy Surfaces

  • Baek, Kyu-Ha;Yoon, Yong-Sun;Park, Jong-Moon;Kwon, Kwang-Ho;Kim, Chang-Il;Nam, Kee-Soo
    • ETRI Journal
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    • 제21권3호
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    • pp.16-21
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    • 1999
  • After etching Al-Cu alloy films using SiCl4/Cl_2/He/CHF3 mixed gas plasma, the corrosion phenomenon at the grain boundary of the etched surface and a passivation layer on the etched surface with an SF6 plasma treatment subsequent to the etching were studied. In Al-Cu alloy system, corrosion occurs rapidly on the etched surface by residual chlorine atoms, and it occurs dominantly at the grain boundaries rather than the crystalline surfaces. To prevent corrosion, the SF6 gas plasma treatment subsequent to etching was carried out. The passivation layer is composed of fluorine-related compounds on the etched Al-Cu surface after the SF6 treatment, and it suppresses effectively corrosion on the surface as the SF6 treatment pressure increases. Corrosion could be suppressed successfully with the SF6 treatment at a total pressure of 300 mTorr. To investigate the reason why corrosion could be suppressed with the SF6 treatment, behaviors of chlorine and fluorine were studied by various analysis techniques. It was also found that the residual chlorine incorporated at the grain boundary of the etched surface accelerated corrosion and could not be removed after the SF6 plasma treatment.

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Genotypic and Geographical Variations of $\beta$amylase Isozyme in Soybean Land Races by Isoelectric Focusing (IEF)

  • Yoon, Mun-Sup;Ahn, Jong-Woong;Kang, Jung-Hoon;Baek, Hyung-Jin;Park, Nam-Kyu;Rho, Yong-Deok
    • 한국작물학회지
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    • 제45권2호
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    • pp.139-142
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    • 2000
  • The experiment was carried out to study the variations and geographical distribution of $\beta$-amylase isozyme by isoelectric focusing (IEF) within Korean, Chinese and Japanese soybean land races. In pH 3-10 gel of IEF, the amylase of soybean accessions was separated into low pI group isozymes (TEX>${$Sp_1$}^b$) and high pI group isozymes(${$Sp_1$}^a$). In pH4-6.5 gel, isoelectric points were at 5.07, 5.15, 5.25, 5.40, and 5.94, and h, j, and k bands also were found. The distribution of Sp$_1$$^{a}$ allele (high pI type) was 29.3% in soybean accessions from Korea, 10.1 % in those from China, and 6.9% in Japanese accessions. The percentage of ${$Sp_1$}^a$) allele was the highest in soybean accessions from Kyungsang province (35 %) in Korea, then central China (32 %) in China, and Honshu (10%) in Japan.

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CNC 기계의 원격 에너지 모니터링을 위한 온라인 시스템 구조 (An On-line System Architecture for Remote Energy Monitoring of CNC Machine Tools)

  • 남성호;송기형;백재용;이동윤;류광열
    • 한국정밀공학회지
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    • 제30권5호
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    • pp.480-485
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    • 2013
  • Enhancing energy efficiency of machine tools causes substantial impacts on the manufacturing industries, to cope with the competitive introduction of the total energy management strategies. Real-time energy monitoring is essential to identify energy consumption patterns of the machine tools and correlate them with the energy management strategy. Integrated analysis of machine tool's operation status and the corresponding energy usage is most important to accurately evaluate the energy efficiency under the various machining process environments. This paper proposes a system architecture to realize the online energy monitoring system and the embedded energy monitoring approach interconnected with the CNC kernel. The shop-floor operation management system is presented to integrate the proposed online energy monitoring approach.

식용 식물자원으로부터 활성물질의 탐색-V. -상추(Lactuca sativa L.)의 ACAT 억제 Diterpenoid, Phytol- (Development of Biologically Active Compound from Edible Plant Sources -V. -Phytol, ACAT (Acyl-CoA: Cholesterol Acyltransferase) Inhibitory Diterpenoid From the Leaves of Lactuca sativa L.-)

  • 장태오;방면호;송명종;홍윤희;김지영;정대균;배동근;권병목;김영국;이현선;김인호;백남인
    • Applied Biological Chemistry
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    • 제46권1호
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    • pp.66-68
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    • 2003

멀티미디어 정보통신 서비스와 인간공학 핵심기술

  • 박범;신용백;김해숙;윤병남;임주환
    • 대한인간공학회:학술대회논문집
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    • 대한인간공학회 1995년도 춘계학술대회논문집
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    • pp.15-15
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    • 1995
  • 90년대 중반에 이르러 세계는 정보화사회로의 진입이 예고되고 있으며21세기는 지 식과 정보로 이루어진 사이버스페이스(Cyberspace)가 지배하는 가상사회(Virtual Society), 그리고 나아가 가상세계(Virtual World)가 될 것이다. Cyberspace는 컴퓨터와 통신망을 통한 다양한 멀티미디어 정보통신 서비스에 의해 형성되는 가상의 공간을 의미한다. 이러 한 21세기 정보화사회의 특성은 사회적 그리고 기술적 Paradigm 변화의 추세와 속성이 변질되고, 정보사회의 변화에 대해 그 근간이 되는 21세기 정보통신기술은 각각 정보의 운반수단, 정보용량, 정보신호처리방식, 통신영역, 그리고 정보통신 자원 등의 영역에서 그 기준과 수준이 변화할 것이다. 본 논문에서는 21세기 사회의 변화에 적응하는 정보통신 기술의 진화 모델과 차세대 정보통신 기술의 예측항목들을 분석하여 지능화(Intelligent), 복합화(Multimedia), 개인화(Human) 등의 IMPH의 특성 요소를 정의 한다. 정보화사회에 있어서 인간 중심의 정보통신 체계(Human Oriented Information and Tele-communication Service System)는 인간의 성능과 특성에 가장 최적합한 서비스 기능 체계를 구축하기 위해서 인간의 각 정보통신 처리 영역인 Perceptual Processor, Cognitive Processor에 대한 구현 서비스들의 정의와 그와 관련하여 예측되는 연구 및 기반기술 과제를 기술한다. 또한, 광대역 멀티미디어 정보통신 서비스들의 형태, 응용, 정보 요소, 기술적인 대칭성과 연결형태 등을 분석하고 4단계로의 차세대 정보통신 기술의 연구개발 전략과 방안을 제시한다.

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누액선에 발생한 Adenoid Cytic Carcinoma - 증 례 보 고 - (Lacrimal Gland Adenoid Cystic Carcinoma - A Case Report -)

  • 서대희;백정환;김윤덕;하범준;박익성;남도현;박관;김종현
    • Journal of Korean Neurosurgical Society
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    • 제29권8호
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    • pp.1089-1093
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    • 2000
  • Adenoid cystic carcinoma(ACC) is a rare malignant tumor that occurs in exocrine glands such as major and minor salivary glands, lacrimal glands, ceruminal glands. It has a tendency for delayed distant metastasis and long clinical course. ACC of the lacrimal gland is generally found in adults and is usually managed by radical orbitectomy and supplemental external beam irradiation. The authors present two cases of recurrent lacrimal gland ACC with review of the literature.

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Genetic Variation in Wild and Cultured Populations of the Sea Squirt Halocynthia roretzi Inferred from Microsatellite DNA Analysis

  • Han, Hyon-Sob;Nam, Bo-Hye;Kang, Jung-Ha;Kim, Yi-Kyoung;Jee, Young-Ju;Hur, Young-Baek;Yoon, Moon-Geun
    • Fisheries and Aquatic Sciences
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    • 제15권2호
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    • pp.151-155
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    • 2012
  • We used nine microsatellite DNA markers to estimate genetic variation among wild and cultured populations of the sea squirt Halocynthia roretzi. The loci were polymorphic, with 6-32 alleles, and allelic richness ranged from 6.0 to 26.1 in each population. The wild and the cultured populations had similar mean heterozygosities ($H_O$ and $H_E$), allele numbers, and allelic richness. One cultured population with softness syndrome had a lower mean in the observed heterozygosity ($H_O$ = 0.57) and higher mean inbreeding coefficient ($F_{IS}$ = 0.261) than any other populations. This suggests that the loss of genetic variation in the diseased population might be due to increased inbreeding. A neighbor-joining tree and pairwise population estimates of $F_{ST}$ showed moderate genetic differentiation between the wild and the cultured populations. Additionally, the softness syndrome population was genetically divergent from wild populations, but it was genetically close to the cultured populations.

브러시리스 직류전동기의 정속도 운전을 위한 디지털 PI제어 (The Digital PI Control for Driving Constant Speed of Brushless DC Motor)

  • 윤신용;김현수;김용;김일남;백수현
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제49권6호
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    • pp.395-402
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    • 2000
  • This paper presents the improvement for speed characteristics of a Brushless DC Motor (BLDCM), it was applied to digital PI control for this. The practical PID control has been widely used to velocity control of DC motors. In this paper, a digital PI controller is used in order to decrease the speed error in constant velocity control of BLDCM. A TMS320C31 DSP is used for the microprocessor of digital PI control. The method using the DSP carry out the real-time control. The DSP has the rapid calculation ability and sampling time used lms. Driving BLDCM used 50W, motor input DC 150V and rotation speed 3000rpm. When BLDCM is to approval for discretion velocity at the acceleration and deceleration driving with any load, it was a feasible for stabilization control. Therefore, the experimental results indicate the superiority and validity of the velocity control by digital PI control.

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식물추출물의 Human-ACAT 저해활성 검색 (Screening for Human ACAT-1 and ACAT-2 Inhibitory Activity of Edible Plant Extracts)

  • 이대영;정태숙;류하나;방면호;홍윤희;이윤형;백남인
    • 한국약용작물학회지
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    • 제16권5호
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    • pp.341-348
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    • 2008
  • Cholesterol acyltransferase (ACAT) catalyzes the acylation of cholesterol to cholesteryl ester with long chain fatty acids and ACAT inhibition is a useful strategy for treating hypercholesterolemia or atherosclerosis. Inhibitory effects on ACAT of the MeOH extracts prepared from 163 edible plants were evaluated. 15 species out of 163 species exhibited higher than 50% of inhibition on the hACAT-1 and 9 species exhibited higher than 50% of inhibition on the hACAT-2 activity at their concentration of $100\;{\mu}g/mL$.