• Journal of Applied Biological Chemistry
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• 제50권3호
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• pp.148-154
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• 2007

Volatile components of the essential oils of Satsuma mandarin (C. unshiu), Dangyuza (C. grandis), Yuza (C. junos), Byungkyul (C. playtymamma), Jinkyul (C. sunki), and Hakyul (C. natsudaidai) grown in Jeju Island were isolated from the fruit peels by hydro distillation and determined by GC-MS. GC-MS analysis identified 58 compounds, with main components being d-limonene $(64.01{\sim}79.34%),\;{\beta}-myrcene\;(3.01{\sim}26.53%),\;{\gamma}-terpinene\;(0.11{\sim}12.88%),\;{\beta}-pinene\;(0.78{\sim}4.74%),\;and\;{\alpha}-pinene\;(1.01{\sim}2.55%)$. Differences in compositions and contents of the essential oils were observed among citrus varieties. Effects of citrus oils on growth inhibitions of Escherchia coli, Staphyllococcus epidermidis, and Candida albicans were investigated using disc diffusion assay and minimal inhibitory concentration (MIC) assay. The essential oils inhibited growths of the test organisms, exhibiting higher levels of activity against Gram-positive S. epidermidis (MIC values $0.04{\sim}0.17mg/mL$), whereas Gram-negative E. coli was moderately resistant (MIC values $1.66{\sim}20.30mg/mL$). MIC of citrus essential oils ranged from $0.82{\sim}23.69mg/mL$ against C. albicans. The essential oils obtained from C. sunki, C. grandis, and C. playtymamma showed the highest antimicrobial activities against S. epidermidis and C. albicans, indicating their potential as natural antimicrobial agents.

• 한국광학회지
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• 제27권2호
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• pp.73-80
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• 2016

본 논문에서는 광생물 반응기의 조명 시스템에 적용할 수 있는 LED(Light-Emitting Diode)와 태양광 하이브리드 광원을 이용한 도광판의 설계 및 제작 결과에 대해 보고한다. LED용 도광판 패턴을 설계하고 기존에 보고된 태양광용 도광판에 함께 중첩하여 가공하였다. 하이브리드 도광판의 출력 PFD(Photon Flux Density)를 일정하게 유지시켜주기 위한 제어 시스템을 제작하였으며, 출력 PFD 목표값을 $70{\mu}E/(m^2{\cdot}s)$로 설정하였을 경우 오차범위 ${\pm}2%$ 이내에서 제어가 이루어짐을 확인하였다.

• 복식문화연구
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• 제17권2호
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• pp.296-308
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• 2009

The purpose of this study is to comprehend the contemporary sports star fashion and to contemplate aesthetic characteristics of sports star fashion, thereby to establish the styles of sports star fashion. For such purposes, this study first examines aesthetic characteristics of sports fashion and star fashion based on previous studies, in order to analyze aesthetic characteristics of sports star fashion, and conducts a case study by analyzing photographic materials of fashion styles of well-known male sports stars such as the English soccer player David Beckham and American golf player Tiger Woods. The result of this study is as follows: the aesthetic characteristics of the contemporary sports star fashion are virility, functionality, sensuality and deconstruction. (1) Virility emphasizes manly features by displaying trained and disciplined body. (2) Functionality is expressed through structural simplicity and temperance of decoration. High-tech textiles and fibers are favored in order to fit in comfortable bodily movement for the heavy exercises. (3) Sensuality, as an expression of indulgence of sexual pleasure, is expressed through bodily exposure. Lastly, (4) deconstruction, which means destroying existed boundaries of cultural categories, is shown as co-existence of design elements from different times and places, stereotypes and sensibilities. Virility and functionality are prominent characteristics expressed in sports uniforms and training costumes. Sensuality and deconstruction are shown in daily fashion and formal dress outside the sports field.

• 한국생활과학회지
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• 제16권5호
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• pp.1061-1068
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• 2007

The study has sought to explore how fashion emerges as a comprehensive tool of dress for increasing its brand appeal and express one's artistic sense and fashion by using everything from make-up to hair to trappings. Therefore, when it comes to fashion trends reflected in collections, the study is designed to improve understanding of make-up as one of the elements of total fashion and to help create diverse ideas in expressing creative and free make-up that can help perfect fashion concept in harmony with all the other elements. The study has pondered upon collection, trends and fashion make-up through literature study, and has gathered image data via the Internet. It also has conducted analysis of Ethnic style reconstructed combining past and the future, East and the West, and futurism style using asymmetrical forms without no defined patterns and hi-tech textures, which emerges as a result of post-modernism. The results of the study are as follows. Ethnic fashion that pursues strange and exotic beauty is characterized by its simple and idyllic images of traditional costume in Asia or primitive clothes in Africa. Make-up represent images of matt and pale skin, tanned yellow, glossy and thickly powered squeaky white skin. Point make-up highlighted eye lines, red chick, small and voluptuous red lips. Hair and accessory seeks diversity combining various ethnic styles together such as oriental, Indian, Islam and Africa. In addition, future-oriented fashion of the 21st century, twists in texture, various kinds of materials and changes in technique help give impressions of freedom and bizarreness.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1018-1021
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• 2006

Powdered metal parts and components may be carburized successfully in a vacuum furnace by combining carburizing technology $VacCarb^{TM}$ with a hi-tech control system. This approach is different from traditional carburizing methods, because vacuum carburizing is a non-equilibrium process. It is not possible to set the carbon potential as in a traditional carburizing atmosphere and control its composition in order to obtain a desired carburized case. This paper presents test results that demonstrate that vacuum carburizing system $VacCarb^{TM}$ carburized P.M. materials faster than traditional steel with acceptable results. In the experiments conducted, PM samples with the lowest density and open porosity showed a dramatic increase in the surface carbon content up to 2.5%C and a 3 times deeper case. Currently the boost-diffusion technique is applied to control the surface carbon content and distribution in the case. In the first boost step, the flow of the carburizing gas has to be sufficient to saturate the austenite, while avoiding soot deposition and formation of massive carbides. To accomplish this goal, the proper gas flow rate has to be calculated. In the case of P.M. parts, more carbon can be absorbed by the part's surface because of the additional internal surface area created by pores present in the carburized case. This amount will depend on the density of the part, the densification grade of the surface layer and the stage of the surface. "as machined" or "as sintered". It is believed that enhanced gas diffusion after initial evacuation of the P.M. parts leads to faster carburization from within the pores, especially when pores are open . surface "as sintered" and interconnected . low density. A serious problem with vacuum carburizing is delivery of the carbon in a uniform manner to the work pieces. This led to the development of the different methods of carburizing gas circulation such as the pulse/pump method or the pulse/pause technique applied in SECO/WARWICK's $VacCarb^{TM}$ Technology. In both cases, each pressure change may deliver fresh carburizing atmosphere into the pores and leads to faster carburization from within the pores. Since today's control of vacuum carburizing is based largely on empirical results, presented experiments may lead to better understanding and improved control of the process.

• Environmental Analysis Health and Toxicology
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• 제20권1호
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• pp.57-65
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• 2005

Effects of five polycyclic aromatic hydrocarbon (PAHs) constituents (naphthalene, fluorine, fluoranthene, benzo(a)pyrene, pyrene) on fertilization and early development of sea urchin egg, sperm and fertilized egg were investigated. The eggs, sperm and fertilized eggs were exposed to several concentrations of PAHs (1, 10, 100, 1000 and 10000㎍/L). The rate of fertilization and hatching decreased when the eggs and sperm were exposed to aqueous solution of PAHs. Also, Exposure of fertilized eggs with each PAHs did decrease survival and hatching rate. Concentration-dependent toxic effects on the rate of fertilization, hatching, survival and abnormality in A. crassispina were observed following exposure to PAHs (1, 10, 100, 1000 and 10000㎍/L). These data show that PAHs exposure decreased in fertilization success of sea urchin egg and sperm and producted abnormal embryo. It is plausible to suggest that PAHs had the potential to significantly reduce coastal recruitment of sea urchin.

• 대한화장품학회지
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• 제33권2호
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• pp.69-77
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• 2007

본 연구에서는 제주도 자생 감귤 17종에 대하여 탈색소효과(depigment effect)를 연구하였다. B16 멜라닌 생성세포(B16 melanoma cell)를 이용하여 tyrosinase 및 멜라닌 생성억제 효과를 연구한 결과 대조군 대비하여 농도 의존적으로 감소하는 3종의 미성숙 온주밀감(immature Citrus unshue), 팔삭(Citrus hassaku), 진지향(Citrus sinensis ${\times}$ reticulata)을 도출하였다. 또한, 이와 같이 도출된 감귤 추출물을 이용하여 멜라닌 세포 생성(melanogenesis)에 영향을 미치는 tyrosinase, DOPAchrome tautomerase (TRP-2)와 DHICA oxidase (TRP-1) 단백질 발현을 실험한 결과 tyrosinase, TRP-1, TRP-2 단백질 발현이 감소함을 나타내었다. 특히 이들 중 미성숙 온주밀감은 tyrosinase와 TRP-1 단백질 발현에서 유의적으로 감소하는 결과를 보였다. 본 연구 결과로써 미성숙 온주밀감은 모든 실험에서 우수한 효과를 나타내어 UV에 의해서 야기되는 피부 색소 침착을 방지할 수 있는 물질로서 기대할 수 있다.

• 컴퓨터교육학회논문지
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• 제3권1호
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• pp.127-134
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• 2000

최첨단 정보통신 기술의 급속한 발전과 구성주의 학습 이론을 기반으로 등장한 원격 교육에서는 학습자가 자신의 학습 과정을 주관함으로써 자신에게 필요한 지식과 기술을 습득하는 자기주도적 학습이 이루어진다. 그러나 웹 기반 원격 교육이나 구성주의에서 학습자 중심적, 주도적 학습을 강조 했을 때 그것이 곧 교사로부터의 해방이나 자유방임적 교육을 의미하는 것은 아니다. 따라서 본 논문에서는 교사 에이전트를 활용하여 학습자를 다양한 수준별로 지도할 수 있는 원격 교육 시스템 모델을 제안하고자 한다. 제안하는 모델에서 교사 에이전트는 학습자 정보를 바탕으로 학습자 개개인의 학습 수준에 맞는 학습 모델을 생성하고 평가에 의해 학업 성취 정도를 파악하여 다음 단계로의 학습 진행 여부를 제어한다. 이를 통하여 웹기반 원격 교육이 제공하는 학습 자원이 아무 목적없이 정보 검색 자체로 활용되는 문제점을 해결하고 진정한 학습자 중심의 교육을 실현할 수 있는 기반을 마련할 수 있다.

• 전기화학회지
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• 제1권1호
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• pp.14-17
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• 1998

MPCF는 Li ion 2차전지용 부극 활물질로 연구되고 있다. 흑연화 MPCF는 높은 방전 용량과 우수한 충방전 효율을 가진다. $0\~1$ V전위영역에서 25 mA/g의 정전류로 충방전할 때의 MPCF/Li전지의 초기 방전 용량은 300 mAh/g이며, 충방전 효율은 $90\%$ 이상을 나타낸다. $LiCoO_2$을 정극 활물질로, 혼합 탄소재료를 부극 활물질로 사용하여 원통형 Li ion 2차전지를 제작하였다. Li ion 2차전지의 수명 특성을 향상하기 위하여, 흑연화 MPCF에 이종 탄소 재료를 $10 wt\%$ 혼합하였다. 혼합 탄소재료를 사용한 Li ion 2차전지의 수명 성능은 흑연화 MPCF만을 사용한 전지보다 우수하였다.

• Spatial Information Research
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• 제18권2호
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• pp.77-88
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• 2010

U-City 서비스로 대표되는 첨단 공간서비스는 그동안 10여년의 많은 노력과 예산투자의 결과로 가시화된 국토정보화(National Digitalization)의 결실로서 평가될 수 있다. U-City서비스는 정보통신기술을 근간으로 하고 있으나 현실공간의 지능화 측면에서 그 개념상 공간정보와 또 그것을 기반으로 국토공간을 분석하고 활용하기 위한 국토 공간계획과 긴밀한 연계관계를 갖지 않을 수 없다. 그러나 아직까지 U-City서비스는 기존의 공간정보 및 공간계획과 명확한 상호관계 설정 및 각 분야간 계획, 구축 및 관리간 연계가 미흡한 실정에 있다. 따라서 본 연구의 주요 목적은 디지털융합시대의 국토 유비쿼터스화라고 하는 큰 명제하에 U-City서비스가 국토 공간정보 및 공간계획과 상호 유기적 연계관계를 가지고 발전할 수 있도록 하기 위한 디지털융합공간(Digital Convergence Space)의 신개념을 제안하고 그 구현을 위한 제도적 정비방안을 제시하는데 있다.