• East Asian mathematical journal
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• v.26 no.2
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• pp.267-280
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• 2010

In this paper we study construction methods of $n^{th}$ line in triangle. Russian Mathematician Zetel suggested some construction methods of $n^{th}$ line in triangle 80 years ago. We find Zetel's papers, in detail explain the Zetel's construction methods, and suggest two elementary construction methods. Our results are received in the process of Research and Education program in science high school.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.379-381
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• 2002

Mitsubishi Electric Corporation has marketed a series of multimedia CRTs enabling bright picture windows in a high-resolution date display screen. The key components of the multimedia CRTs named Diamondtran $M^2$ are a high-gm (low drive-voltage) electron gun and an aperture grille mask. A high-gm electron gun has been developed by designing a beam forming region with high-gm configuration combining with a high current-density cathode. The development of next generation high-gm guns are also introduced

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.378-380
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• 2002

There has been lower the tilt margin by the increase of coma aberration due to the reduction of wave-length and the increase of numerical aperture for high density recording. The RF signal degradation is increased as the decrease of tilt margin. To compensate the tilt margin, the optical pick-up actuator for high-speed CD/DVD re-writable system should be able to drive the radial-tilt motion. We announce that the 3-axis drive actuator for high-speed CD/DVD rewritable system. And what was more, the DC/AC sensitivities of this actuator are suitable fur the low-speed playability, the high-speed readability and the high-speed rewritability.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.11
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• pp.628-634
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• 2002

A capacitor-charging power supply using high frequency inverter technology is strongly recommended for the charging section of the pulsed power supplies. A high frequency inverter swiching makes the overall system size small. The command-charging feature can guarantee the higher reliability of switching function. The protection circuit can be easily included in the system and the good regulation of charging voltage can be acieved by the feedback system. Several modules can be stacked to supply required output power and a failed module can be easily replaced. A 50-kV, 35-kW capacitor charging power supply is developed. In this paper the detailed design and test results of a prototype unit are presented.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.70-76
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• 2006

Anti-obesity effect of biocellulose and diet formulation containing it was evaluated using obese rats. Thirty male Sprague-Dawlely (SD) rats were randomly assigned to high-fat diet group (CON), high-fat diet group containing 5% biocellulose (BIO), and high-fat diet group containing 5% dietary formulation (DF). After 10 weeks, body weight gains of BIO and DF groups were reduced by 15.1 and 6%, respectively, as compared with CON group. Epididymus, parirenal, and visceral fat pads of BIO and DF groups were lower than those of CON group. Weight of interscapular brown adipose tissues increased slightly in BIO group and significantly in DF group. Size of adipocyte in rats decreased in BIO and DF groups. Results indicate biocellulose-containing diet has anti-obesity effect by reducing body weight gain and white adipocytes depots in rats fed high-fat diet.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2511-2512
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• 2001

디스크의 탄젠셜 성분의 틸트가 생긴 경우 발생하는 체널의 변화에 대해 적응형 부분 응답 신호처리 과정인 비터비 디코더를 적용하게 되면 비트오율에 상당한 효과를 가져온다. 이러한 적응 과정을 효과적으로 진행하기 위한 간략화된 오류 발생 알고리즘을 제안한다.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.460-463
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• 1993

In this paper, The laser transmitter module is designed as the subsystem of the high repetitive laser rangefinder. The module consists of high voltage power supply, high voltage control circuits, high voltage discharger, electro-optic Q-switch driver, and laser resonator. The high voltage power supply is composed of 2-phase flyback converter. And it has 220W power level and 78% conversion efficiency. From the Q-switch driver of the crossed porro resonator, the phase retardation voltage is switched from 600V to -1500V with 200ns falling time. The module can be operated up to 15Hz. And it generates the laser pulse which has 20ns width and 80mJ.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1516-1517
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• 2007

This paper investigated the breakdown effect of the CMOS device by impact of high power electromagnetic wave. The experiments employed a waveguide to study the current characteristics of CMOS device broken by high power electromagnetic wave. The CMOS device were composed of a LED drive circuit for visual discernment. Also CMOS device broken by high power electromagnetic wave was observed by power current. The CMOS device were broke by high power electromagnetic wave at about 10 kV/m and when power current is 75 mA. Based on the result, CMOS devices should show plan to protect the CMOS devices by high power electromagnetic wave. And the database from this experiment should provide the basis for future investigation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.262-263
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• 2008

The Metal-Insulator-Silicon (MIS) capacitors with $SiO_2$ and high-k dielectric were investigated. The high-k dielectrics were obtained by atomic layer deposit (ALD) system. The electrical characteristics were investigated by measuring the current-voltage (I-V) characteristics. The conduction mechanisms were analyzed by using the Fowler-Nordheim (FN) plot and Direct Tunneling (DT) plot. As a result, the MIS capacitors with high-k dielectrics have lower leakage current densities than conventional tunnel-barrier with $SiO_2$ dielectrics.

• Applied Science and Convergence Technology
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• v.24 no.6
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• pp.250-253
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• 2015

High contrast grating (HCG) is the structure made up of the sub-wavelength grating of high-index and the surrounding layer of low-index, which reveals high contrast between two materials. Its advantages include high reflectivity over a broad bandwidth, polarization and wavelength selectivity, optical high-Q resonator, and phase modulation. In this work, the HCG structure comprising of indium tin oxide (ITO) and Silicon (Si), for the surrounding layer and the grating layer respectively, was studied. Its theoretical model was established, and transmittance, phase and optical behavior were calculated by rigorous coupled-wave analysis and finite element method. Furthermore, the established structure was fabricated to validate its feasibility. The fabricated structure shows the focusing capability whose length is about $10{\mu}m$, and the feasibility of the structure was demonstrated. It is also meaningful that ITO layer can contribute to the fabrication of the HCG structure, leading to enable the structure to be electrical-driven.