• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.5
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• pp.18-23
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• 2004

Wind tunnel test for Forward-Swept wing airplane model, a part of the Korea-Russia technical cooperation program has been conducted at both TsAGI T-102 and KARI LSWT. The results of TsAGI T-102, obtained by using a unique wire-suspension model support system, and KARI LSWT, used tripod and tandem strut arrangement configuration, are compared with various model conditions including control surface deflection such as flap, aileron, elevator and rudder. Good agreement in the value of drag-polar is observed between TsAGI T-102 and KARI LSWT data. The lateral and directional stability coefficients with rudder and aileron deflection represent a good agreement in both facility.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.8
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• pp.10-19
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• 2007

Use of various lighting simulation software has been increased Lighting simulation software can be categorized into two types. One is for optical design while the other is for estimation and analysis of lighting design. Photopia 2.0 is typical software for optical design of a luminare and Lumen-micro 2000, Relux 2006, Lightscape 3.2 and AGI 32 are software for lighting design. Through using various lighting simulation software some different results can be found under the same conditions. Therefore, the purpose of this paper is to compare measured and simulated photometric data of different types of luminaires and to compare simulated values from Lumen-micro 2000, Relux 2006, Lightscape 3.2 and AGI 32 under the same conditions. In addition, the reasons for such differences are analyzed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.58-62
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• 2017

In this study, the design conditions for the Korean-style glass greenhouse structure has been reduced to achieve the most efficient use of natural light. The AGI program was simulated for the optimal conditions of daylight in a glass greenhouse. From the results of daylight simulation, the axis position of the glass greenhouse's roof was not an important factor in the daylight effects regarding illumination and uniformity. In summer, there were long periods of daylight and high illumination levels. The illumination value of daylighting increased with increasing glass transparency value, and the illumination value was greatest at 14:00 hours. At this time, the rate of light variation according to the glass transparency was 89 [lux/%]. In addition, the optimal design conditions for the glass greenhouse were established, which were a $30[^{\circ}]$ or $150[^{\circ}]$ installation angle and higher transmittance of glass.

• Journal of Astronomy and Space Sciences
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• v.32 no.4
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• pp.411-417
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• 2015

Several optical monitoring strategies by a ground-based telescope to protect a Geostationary Earth Orbit (GEO) satellite from collisions with close approaching objects were investigated. Geostationary Transfer Orbit (GTO) objects, Inclined GeoSynchronous Orbit (IGSO) objects, and drifted GEO objects forced by natural perturbations are hazardous to operational GEO satellites regarding issues related to close approaches. The status of these objects was analyzed on the basis of their orbital characteristics in Two-Line Element (TLE) data from the Joint Space Operation Center (JSpOC). We confirmed the conjunction probability with all catalogued objects for the domestic operational GEO satellite, Communication, Ocean and Meteorological Satellite (COMS) using the Conjunction Analysis Tools by Analytical Graphics, Inc (AGI). The longitudinal drift rates of GeoSynchronous Orbit (GSO) objects were calculated, with an analytic method and they were confirmed using the Systems Tool Kit by AGI. The required monitoring area was determined from the expected drift duration and inclination of the simulated target. The optical monitoring strategy for the target area was analyzed through the orbit determination accuracy. For this purpose, the close approach of Russian satellite Raduga 1-7 to Korean COMS in 2011 was selected.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.96-96
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• 2019

Sedum kamchaticum, Sedum middendorffianum and Sedum takesimense belong to the sebum species. Especially, Sedum takesimense is a Korean native species growing only on Ullenung-do. Few studies for the biological activities of these plants have been reported. In this study, we examined biological activity and the contents of functional components of the aerial part and the root part of Sedum kamchaticum, Sedum middendorffianum and Sedum takesimense. As the results, the roots of Sedum takesimense showed the highest total phenolic contents (TPC : $13040{\pm}50.0mg\;GAE{\cdot}100g^{-1}$), and the aerial part of Sedum takesimens showed the highest total flavonoid contents (TFC : $2722.2{\pm}107.1mg\;CAE{\cdot}100g^{-1}$). Meanwhile, Sedum middendorffianum exhibited the highest anti-oxidant activity (DPPH $RC_{50}$ value of aerial part : $50.69{\pm}0.75{\mu}g{\cdot}mL^{-1}$, DPPH $RC_{50}$ value of root part : $27.27{\pm}0.55{\mu}g{\cdot}mL^{-1}$; ABTS $RC_{50}$ value of aerial part : $11.32{\pm}0.38{\mu}g{\cdot}mL^{-1}$, ABTS $RC_{50}$ value of roots part $5.54{\pm}0.02{\mu}g{\cdot}mL^{-1}$). The root part of Sedum middendorffianum showed the potent alpha glucosidase inhibitory activity (AGI $IC_{50}$ : $60.69{\pm}0.72{\mu}g{\cdot}mL^{-1}$). In order to elucidate active principle of Sedum middendorffianum that was shown the most potent antioxidant and anti-diabetic activities, the methanol extract of Sedum middendorffianum was fractionated with various solvents according to the polarity successively. As a result, EtOAc fraction of Sedum middendorffianum showed the highest contents of functional components (TPC : $16245.8{\pm}1025.7mg\;GAE{\cdot}100g^{-1}$, TFC : $4850.4{\pm}182.9mg\;CAE{\cdot}100g^{-1}$). And it also showed excellent anti-oxidant activities (DPPH $RC_{50}$ : $14.0{\pm}0.6{\mu}g{\cdot}mL^{-1}$, ABTS $RC_{50}$ : $3.4{\pm}0.1{\mu}g{\cdot}mL^{-1}$) and anti-diabetic activity (AGI $IC_{50}$ : $79.0{\pm}2.2{\mu}g{\cdot}mL^{-1}$). Above results suggest that Sedum middendorffianum can be developed to health functional material as a plant resource with potent antioxidant activity.

• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.25-32
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• 2021

Phytochemicals include plant-derived natural products that promote and improve the human metabolism and physiological activity, and there is a lot of research to find the value of the molecules is in progress. Likewise, we obtained 288 fractions of Capsicum annuum L. extract in less than 20 h using HPLC/SPE/HPLC coupling experiment through Sepbox system, an effective separation system to search for active substances in natural resources and ensure efficacy and reliability. Therefore, this experiment allowed rapid identification of biologically active molecules from the extract compared to traditional separation processes. Of the above fractions, eight fractions showed the α-glucosidase inhibitory (AGI) activity and subsequent LC-MS analysis revealed one of the active molecules as luteolin 7-O-glucoside. In addition, we proved the increase in AGI activity according to deglycosylation of flavonoid glycoside. Therefore, this study suggests that the Sepbox system can quickly separate and identify active components from plant extract, and is an effective technique for finding new active substances.