• 대한산업공학회지
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• 제33권3호
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• pp.349-354
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• 2007

A mixture experiment is a special type of the response surface experiment in which the factors are the components of a mixture, and the response variable is a function of the proportions of each component. When a new mixture product is developed, there are a large number of components, and the first objective of the experiment is to identify the ones that are most important by doing a screening experiment. We propose a method of screening mixture components using the correlation coefficients when t-tests cannot identify significant components.

• 한국군사과학기술학회지
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• 제14권6호
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• pp.1049-1057
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• 2011

Today, most weapon systems operate as component systems of SoS(System of Systems) and they produce synergy effects in the battle field by interoperating. In addition, the acquisition issues on weapon systems have expanded into SoS context including sustainment analysis. Availability is the sustainment KPP(Key Performance Parameter) of weapon systems. In this paper, a simulation model is proposed to analyze the availability of SoS. The simulation model consists of 5 modules: Mission and Task, System, System RBD, Maintenance system and a simulation engine. Then it was implemented and applied to a SoS. As a result of the application, the simulation model could be applied for analyzing the availability of the SoS and provided information about critical tasks and risky component systems to complete the given mission of the SoS.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.197-199
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• 2002

This paper describes the effects of chip arrangement configurations and the dimension of a reflecting cup upon the light output characteristics of a white lamp composed of RGB LED chips. As a result of simulation, the shorter distance between adjacent chips leads to a relative decrease in the light output efficiency due to inter-chip absorption of quanta, but rather uniform color mixing is expected. Among the factors of designing a reflecting cup it is the tilt angle of the cup wall that plays a determining role upon the variation of the light distribution. The light distribution shows a sudden change of pattern from Lambertian to Batwing at about $35^{\circ}{\sim}40^{\circ}$ of tilt angle in case of a silver-coated wall cup.

• Natural Product Sciences
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• 제13권2호
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• pp.164-168
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• 2007

To investigate natural antibiotics from plant essential oils and to evaluate their synergism with current antimicrobial drugs in inhibiting antibiotic-resistant strains of Streptococcus pneumoniae. The minimal inhibitory concentrations (MICs) of eleven plant essential oils and their main components were established for two antibiotic-susceptible and two antibiotic-resistant strains of S. pneumoniae, using broth microdilution tests. Potential synergism with oxacillin, norfloxacin, or erythromycin was evaluated using a checkerboard microtitre assay. Among the tested oils, Mentha piperita oil and its main component, menthol, exhibited the strongest inhibitory activities against all of the tested strains. The activity of antibiotics against antibiotic-resistant strains of S. pneumoniae was enhanced significantly by combination with Mentha piperita oils and its main component, menthol. In conclusion, the combination Mentha piperita essential oil or menthol with antibiotics could be used to reduce the effective dose of antibiotic and to modulate the resistance of S. pneumoniae strains.

• Journal of Multimedia Information System
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• 제5권2호
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• pp.87-90
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• 2018

Various approaches have been proposed to convert low dynamic range (LDR) to high dynamic range (HDR). Of these approaches, the Multi Scale Fusion (MSF) algorithm based on Laplacian pyramid decomposition is used in many applications and demonstrates its usefulness. However, the pyramid fusion technique has no means for controlling the luminance component because the total number of pixels decreases as the pyramid rises to the upper layer. In this paper, we extract the reflection light of the image based on the Retinex theory and generate the weight map by adjusting the reflection component. This weighting map is applied to achieve an MSF-like effect during image fusion and provides an opportunity to control the brightness components. Experimental results show that the proposed method maintains the total number of pixels and exhibits similar effects to the conventional method.

• Bulletin of the Korean Chemical Society
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• 제20권12호
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• pp.1501-1505
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• 1999

Expansion dynamics of C$^{+}$ ions ejected from 355-nm laser ablation of graphite target in vacuum has been investigated by pulsed-field time-of-flight (TOF) mass spectrometry. A strong nonlinear dependence of the amount of desorbed C$^{+}$ ions on laser fluence is interpreted by the mechanism that C$^{+}$ ions are produced directly from the graphite via conversion of the multiphoton energy into thermal energy. The temporal evolution of C$^{+}$ ions was measured by varying the delay time of the ion repelling pulse with respect to the laser irradiation, which provides significant information on the ablated plume characterization. The TOF distributions of ablated ions showed a bimodal shape and could be fitted by shifted Maxwell-Boltzmann distributions. The velocity of the fast component increases with the delay time, whereas the slow component (< 500 m/s) exhibits a constant velocity. Also studied were the effects of the laser fluence on the energetics of C$^{+}$ ions.

• Journal of Ginseng Research
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• 제20권2호
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• pp.173-178
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• 1996

Aerobic cells are normally protected from the damage of free radicals by antioxidative on , zymes such as superoxide dismutase (SOD), catalase, glutathione (GSH) peroxidase, GSH S- transferase and GSH reductase which scavenge free radicals as well as nonenzymatic antioxidants such as ceruloplasmin, albumin and nonprotein-SH including GSH. The effects of each component (ginsenoside $Rb_1$, $Rb_2$, Rc, Rd, Re, $Rb_1$, Rf, $Rh_1$ and $Rh_2$) of red ginseng on the antioxidative enzyme activities were investigated in the liver in order to screen antioxidative components of red ginseng. Ginsenoside $Rb_1$ and Rc showed a tendency to increase GSH peroxidase activity, while ginsenoside Rc significantly decreased Cu,Zn-SOD activity. Especially, ginsenoside $Rh_2$ significantly increased catalase activity. These results suggest that ginsenoside $Rh_2$ is an important active component among total saponins of red ginseng.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.379.2-379.2
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• 2002

Angelicae tenuissimae ia a plant often used in traditional Korean medicine. It has been used as analgesic. antipyretic and anti-inflammatory agent. However its component and precise modes of neuropharmacological action have not been reported. In the present study, we investigated the protective effects of A. tenuissimae and it's component on ischemic damage induced by oxygen and glucose deprivation in rat hippocampal slice. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.321.1-321.1
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• 2002

To indentify inhibitors of melanogenesis. we compared the effect of some natural products on mushroom tyrosinase. human melanocytic tyrosinase activity and melanin content. The cytotoxicity of the component were also tested on cultured mouse melanoma cells, Each extract significantly inhibited tyrosinase activity and melanin synthesis in vitro and B 16 melanoma cell lines. In B 16 cell lines, watermelon's inner shell extract inhibited tyrosinase activity as strong as kojic acid at 150${\um}g$/${\mu}\ell$ concentration. And morning glory'seed extract inhibited melanin synthesis more than kojic acid at 150${\um}g$/${\mu}\ell$ concentration. Each extract were strong inhibitors of tyrosinase activity and total melanin synthesis in B 16 mouse melanoma cell lines at less than 100${\um}g$/${\mu}\ell$ concetration. These result show that extract of watermelon's inner shell. lettuce. morning glory's seed and licorice root could be developed as skin whitening component of cosmetics.

• 한국산업정보학회논문지
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• 제11권4호
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• pp.93-104
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• 2006

본 논문은 도면관리 시스템과 BOM 시스템간의 데이터 공유를 통하여 효과적인 BOM산출을 시도하였다. 본 논문에서는 이러한 목적을 달성하기 위해서 본 논문에서는 CAD도면을 이용한 컴포넌트 기반 소프트웨어 시스템을 구현하였다. 본 연구의 결과로는 BOM 산출을 하는데 있어서 여러 번의 시행착오를 거쳐야하는 문제점들을 현저히 감소시켰다. 특히 본 연구의 결과로는 BOM의 산출 기간이 2주에서 2일로 단축되었으며, BOM 산출의 정확도는 95%에 도달하였다. 본 논문에서는 이 이외에도 다음과 같은 효과를 가져왔다. 첫째, 컴포넌트 개발 방법으로 인한 프로그램의 재사용성, 유지/보수 및 수정의 용이성 둘째, 웹 기반 개발 기법으로 인한 원격지에서의 시스템 운영 가능, 셋째, 이미지 및 텍스트 데이터베이스 구축으로 인한 데이터 관리의 효율화 넷째, 도면관리의 체계화, 다섯째, 회사에 적합한 맞춤형 BOM시스템 구현 등이다.