• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.609-614
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• 2013

Extended H$\ddot{u}$ckel tight-binding band structure calculations are used to address the chemical bonding and elastic properties of $Zr_2AC$ (A=Al, Si, P, and S). Elastic properties are interpreted by analyzing the density of states and the crystal orbital overlap population for the respective phases. Our results show that the bulk modulus of these ternary compounds is determined by the strength of Zr-A bonds.

• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.32-37
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• 2006

ETRI has been developing the Ka-band Antenna subsystem for COMS(Communications, Ocean, and Meteorological Satellite) which will be launched at the end of 2008. The antenna subsystem employs the two parts: East Panel and West panel of spacecraft. ETRI in cooperation with domestic companies are under design phase for the antenna subsystem development. This paper focuses in the Ka-band reflector pointing error analysis to verify the antenna subsystem performance specification, especially EOC gain variation etc. The analysis performed is that induced by reflector surface deformation as a result of thermo elastic distortion. Beam pattern variations are verified by the use TICRA

• Journal of Ginseng Research
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• v.17 no.2
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• pp.153-158
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• 1993

The study was carried out for comparison of variants and development of genetic markers using Randomly Amplified Polymorphic D사A (RAPD) analysis method. The ginseng variants used were as follows: Chungkyung-Chong, Hwangskoog-Chong, KG101 selected by the pureline selection method, and 6 kinds of Jakyung-Chong strains Uinjakyung, Jakyung-Chong 81783, Jakyung-Chong 847913, Jaky tong-Chong 79742, Jinjakyung of USSR, and Mimaki of Japan). Four of 10 RAPD primers showed the distinctive polymorphism among 9 ginseng variants and lines, and were selected for more detailed polymorphic analysis. The sequences of 4 selected primers were TGCCGAGCTG (Primer#2), AATCGGGCTG (#4), GAAACGGGTG (U7), and GTGACGTAGG (#8). All primers produced several common bands among the strains. However, when primer # 2 was applied, the electrophoregram showed the specific band at 1.8 kb region in Chungkyung-Chong, Hwangskoog- chong, and KG101, and 1 kb in the Jakyung-Chong 847913. In primer #4, 1.1 kb band was shown in Chungkyung-Chong, Hwangskoog-Chong, KG101, and Jakyung-Chong 79742. In primer # 7, 700 bp band was appeared in Jakyung-Chong 81783 and Jinjakyung of USSR In primer # 8, 800 bp band was observed only in Mimaki, comparing to another strains. When Similarity Index (SI) was calculated, Chungkyung-Chong and Hwngskoog-Chong, and Jakyung- chong 81783 and Jinjakyung of USSR showed the most close SI, 0.11 and 0.08, respectively. The data of KG101, which showed the SI of 0.13 with the group of Chungkyung-Chong and Hwangskoog-Chong, coincided with the fact that it was released from Hwangskoog-Chong by breeding process. The data of Jakyung strains indicated the significant variation among the strains. From these results, RAPD analysis method could be succesively applied to the classification and genetic analysis for breeding of Korean ginseng.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.9
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• pp.944-949
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• 2003

In this paper, the double balance mixer(DBM) for Ku-band LNB using InGaP/GaAs HBT process is suggested for the characteristics of low DC power consumption, low noise figure, low intermodulation distortion and wide dynamic range. The 5 dB conversion gain, 14 dB NF, bandwidth 17.9 GHz and 50.34 dBc IMD are obtained under RF input power of -23 dBm, with bias condition as 3 V and 16 mA. The linearity of InGaP/GaAs HBT, the broad band input matching scheme and the optimization of bias point result in the low IMD, the broad bandwidth and the low power consumption characteristics.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.234-234
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• 2010

The PR transitions in asymmetric dot-in-double-quantum-well (DdWELL) photodetector is identified by bias-dependent spectral behaviors. Discrete n-i-n infrared photodetectors were fabricated on a 30-period asymmetric InAs-QD/[InGaAs/GaAs]/AlGaAs DdWELL wafer that was prepared by MBE technique. A 2.0-monolayer (ML) InAs QD ensemble was embedded in upper combined well of InGaAs/GaAs and each stack is separated by a 50-nm AlGaAs barrier. Each pixel has circular aperture of 300 um in diameter, and the mesa cell ($410{\times}410\;{\mu}m^2$) was defined by shallow etching. PR measurements were performed in the spectral range of $3{\sim}13\;{\mu}m$ (~ 100-400 meV) by using a Fourier-transform infrared (FTIR) spectrometer and a low-noise preamplifier. The asymmetric photodetector exhibits unique transition behaviors that near-/far-infrared (NIR/FIR) photoresponse (PR) bands are blue/red shifted by the electric field, contrasted to mid-infrared (MIR) with no dependence. In addition, the MIR-FIR dual-band spectra change into single-band feature by the polarity. A four-level energy band model is proposed for the transition scheme, and the field dependence of FIR bands numerically calculated by a simplified DdWELL structure is in good agreement with that of the PR spectra. The wavelength shift by the field strength and the spectral change by the polarity are discussed on the basis of four-level transition.

• Journal of the Korean Chemical Society
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• v.37 no.1
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• pp.36-42
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• 1993

In the presence of $Ca^{2+}$ ion, the charge transfer (CT) interaction of nonionic surfactants, $nonylphenol-(ethylene oxide)_n\;[NP-(EO)_n; n = 11, 40, 100]$ with iodine in aqueous solution were investigated by UV-visible spectrophotometer. The characteristics of spectra depended on the concentration of $Ca^{2+}$ ion and the number of EO unit. Above CMC, the intensity of the CT band by the addition of $Ca^{2+}$ ion for the $NP-(EO)_{11}$ and $NP-(EO)_{40}$ increased and then decreased, while for the $NP-(EO)_{100}$ continuously increased. The increase in the intensity of CT band were attributed to the compactness of micelle in the presence of $Ca^{2+}$ ion. These phenomena may be explained by the fact that the linear ethylene oxide (EO) chain, to be free configuration in aqueous solution, could form a pseudo-crown ether structures capable of forming complexes with $Ca^{2+}$ ion.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.141-146
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• 1976

1) The purified enzyme was obtained with the specific activity 126.5 u/mg protein (about 45 times of the original activity) and the yield of 4.2%, by means of salting out with ammonium sulfate (0.5 saturation) of the crude enzyme solution, desalting by Sephadex G 25, CM cellulose columm chromatography, concentration by Sephadex G 25, and gel filtration by Sephadex G 75. 2) In the acrylamide gel disc electrophoresis of the purified enzyme, the main band and two obscure ones on the both side of the main band appeared, which indicated that the enzyme was considerably purified compared with its crude enzyme solution, even if it is not referred to as a pure protein.

• Journal of Pharmacopuncture
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• v.3 no.2
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• pp.153-168
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• 2000

This study was designed to study on major components of various Bee Venom(Bee Venom by electrical stimulation in Korea; K-BV I, Bee Venom by Microwave stimulation in Korea; K -BV II, 0.5rng/ml, Fu Yu Pharmaceutical Factory, China; C-BV, 1mg /ml, Monmouth Pain Institute, Inc., U.S.A.; A-BV) using Electrophoresis. The results were summarized as follows: 1. In 1:4000 Bee Venom solution rate, the band was not displayed distinctly usmg Electrophoresis. But in 1: 1000, the band showed clearly. 2. The results of Electrophoresis at solution rate 1:1000, K-BV I and K-BVII showed similar band. 3. The molecular weight of Phospholipase $A_2$ was known as 19,000 but its band was seen at 17,000 in Electrophoresis. 4. Protein concentration of Bee Venom by Lowry method was different at solution rate 1:4000 ; C-BV was $250{wmu}g/ml,\;K-BV\;I\;was\;190{wmu}g/ml,\;K-BVII\;was\;160{wmu}/ml\;and\;C-BV\;was\;45{wmu}/ml5$. Electrophoresis method was unuseful for analysis of Bee Venom when solution rate is above 1:4000 but Protein concentration of Bee Venom by Lowry method was possible. These data from the study can be applied to establish the standard measurement of Bee Venom and prevent pure bee venom from mixing of another components. I think it is desirable to study more about safety of Bee Venom as time goes by.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.467-470
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• 2009

본 논문에서는 유비쿼터스 기반 인프라를 이용한 실시간 유괴방지 시스템을 구축하였다. 급속한 사회 발전과 더불어 강력사건이 증가되고 있으며 그중에서 어린이 유괴 범죄 같이 질적으로 흉악한 범죄가 해마다 증가되고 있는 실정이다. 이러한 유괴 범죄를 예방하기 위하여 현재 GPS(Global Positioning System)을 이용한 위치인식 기술 및 이동통신 기지국을 이용한 위치인식 기술이 사용되고 있다. 단순히 위치인식 기술은 위험상황이 발생하였을 때, 상황을 정확히 인지하기 어려워 유괴된 어린이 44%가 1시간 이내 사망하고 74%가 3시간 이내 사망 한다는 통계를 감안하면 기존 시스템은 어린이 생명 보호 능력에 한계가 있다. 본 연구에서는 유비쿼터스 도시 기반 인프라를 구축하여 WPAN(Wireless Personal Area Network)환경에서 RF만으로 거리 측정이 가능한 IEEE 802.15.4a의 ISM Band CSS(Chirp Spread Spectrum)방식을 이용하여 보다 저 전력으로 정확한 위치정보 시스템을 적용하였다. 이에 CSS방식을 통하여 얻은 위치정보를 지능형 CCTV와 융합하여 CCTV가 단말기 위치로 자동 초점하는 시스템을 구성하였다. 도시통합운영센터에서 상황을 정확히 인지하고 신속하게 출동할 수 있도록 단말기 위치를 지속적으로 요원의 PDA 및 핸드폰으로 통보하고 현장 주변의 미디어 보드 표시와 음성 경고로 경찰의 적절한 대응 및 주변의 도움을 받을 수 있는 시스템을 구성하였다.

• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.38-44
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• 2006

The COMS(Communication, Ocean & Meteorological Satellite) is the geostationary satellite which will be performing three main objectives such as meteorological service, ocean monitoring and Ka-band satellite communications. In order to accomplish these missions, the COMS system needs to implement a specific electrical/mechanical interface functions which are requested by each payload units. This paper describes a on-board interface hardware design for COMS Meteorological Imager(MI). The Meteorological Imager Interface Unit(MI2U) achieves, through MIL-STD-15533 system bus, the interface between the Spacecraft Computer Unit(SCU) and the instrument which is dedicated to MI. MI2U provides a necessary power input to MI from +50V Power Supply Regulator(PSR), and allows adaptation of the specific payload interfaces and protocol to COMS spacecraft.