• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.10a
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• pp.40-44
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• 1986

The cassegrain antenna, 32metor , diameter, is designed for the satellite earth station at Boun. It is fed by a beam waveguide of type. The results of measurements G/T (Gain to Noise Temperature ratio) is 40.86dB/K at the elevation elevation angle 5˚ for 4GHz. And the average transmit and receive gain are 64.62dB and 61.3dB, respectively. They satisfy the values designed for the antenna. The sidelobe levels of the pattern also are in good accord with the recommendation of C.C.I.R.

• Review of KIISC
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• v.17 no.6
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• pp.57-66
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• 2007

보호프로파일이란 공통평가기준에서 IT제품에 대한 특정 소비자의 보안요구사항을 담은 문서로써, 소비자 그룹과 이해 집단이 그들의 보안 요구를 표현할 수 있도록 보안목표명세서 작성을 쉽게 하기 위하여 제공한다. 최근 들어 많은 국가기관, 기업에 의해 보호프로파일 개발이 요구되고 있지만, 일관성 있는 보증등급 산정 방법이 제시되어 있지 않아 보호프로 파일 개발에 어려움이 있다. 따라서 본 고에서는 공통평가기준 버전 3.1의 보호프로파일 내용을 분석하고, 미국의 견고성(Robustness)을 이용한 보호프로파일 개발체계를 분석한다. 그리고 국외의 보호프로파일 보증등급 산정기준 동향을 분석한 후, 국내 환경에 맞는 보증등급 산정 방법론을 제안한다.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.191-194
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• 2000

A 2.4 GHz single ended two stage low noise amplifier(LNA) is designed for Bluetooth application. The circuit was implemented in a standard digital 0.25 $\mu\textrm{m}$ CMOS process with one poly and five metal layers. At 2.4 GHz, the LNA dissipates 34.5 mW from a 2.5V power supply voltage and provides 24.6 dB power gain, 2.85 dB minimum noise figure, -66.3 dB reverse isolation, and an output 1-dB compression level of 8.5 dBm.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.195-198
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• 2000

A CMOS power amplifier for wireless home networks is designed using 0.2sum 1-poly 5-metal standard CMOS technology and simulation results are presented. The power amplifier provides maximum output power of 16.5dBm to a 50-Ohm load at 2.450Hz and dissipates 220mW of dc power from a single 2.5-V supply. The designed CMOS power amplifier has power control range of 20dB and an overall power-added efficiency of 17%

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.2
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• pp.125-129
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• 1988

The acattering characteristics by the TE incident wave are analysed for its dielectric cylinder with arbitrary cross section partially covered by thin conductors. The integro differential equations consistent with boundary conditions of conductors and dielectric boundaries are derived by the equivalence principle. They are transformed into matrix equations by moment method. The rectangular dielectric ctlinder partially coverd by conductors at the upper and bottom side of the cylinder is chosen for the numerical example. Current distributions on conductors and sacttring cross sections by the cylinder are computed for the TE incident perpendicular to the conductor plane.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.646-655
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• 2002

장대 교량이 위치한 지반에서 지진에 의한 지반 운동은 교량의 길이 방향으로 공간적인 변화를 일으킨다. 지형 변화나 지반 매질의 물성 변화가 있는 비균질한 지반에서 지반 운동의 진폭과 주파수 성분은 변화하고 이 부지 효과(site effect)는 교량의 지진 응답에 지배적인 영향을 미치며 그 영향은 파전파 효과(wave passage effect)에 의한 지반 각 지점의 지진파 도달시간 차이나 비균질성이 큰 지반에서 파의 다중 반사, 굴절에 의한 영향보다 크다[1]. (중략)

• Bulletin of Food Technology
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• v.10 no.4
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• pp.10-22
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• 1997

WTO 체제 하에서 전세계적으로 모든 분야에 대한 국제적인 개방화가 요구되고 있는 현 시점에서 선진국의 산업재산권 공세가 더욱 강화되고 있으나 식품분야의 국내의 대응능력이 매우 약한 것이 그 현실입니다. 본고는 그 대응책의 일환으로 추진되고 있는 산업재산권 진단사업의 포괄적인 내용 소개와 아울러 1997년도 우리연구원이 수행한 진단과제(녹차 농축물 제조방법)에 대한 사례를 소개합니다. 본 사업을 통하여 좀더 철저한 기술 분석 및 연구개발을 통해 국제적으로도 손색없는 우수한 제품을 개발하고 산/학/연/관의 협조체제의 틀 속에서 완벽한 산업재산권을 획득할 수 있는 기틀을 마련하시기 바랍니다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.3
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• pp.515-522
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• 1994

The radiation characteristics of the conical corrugated feed horn are analyzed by the Gaussian beam mode theory. the electric field over the aperture can be expanded in terms of a set of Gaussian-Laguerre modes. It is proved that these modes are the solutions of the wave epuations for the paraxial approximation. A method, using the sum of the mode expansion coefficients instead of calculation only the fundamental mode, is presented in order to reduce the radiation pattern error. For illustrative examples, the radiation patterns of the corrugated horn antenna operting over C, Ku, and mm-wave band are calculated. Our results agree well with the results obtained by the vector potential method over each band, and also agree well with the measured value at 6.175GHz.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.6
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• pp.462-469
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• 1988

Choromatic dispersion of single mode optical fibers limits the maximum bit rate in the single mode optical transmission systems. In this paper we calculate chromatic dispersion and dispersion parametes(zero dispersion wavelength, dispersion slope) for concatenated single mode optical fibers form the chromatic dispersion and dispersion parameters of individual single mode optical fibers, and compare theoretical valuse with those measrued by double demodulation method. Calculated values are coincident with measured ones reasonably. The standard deviation is 0.77-1.28nm for zero dispersion wavelength and 0.56-0.75PS/km.nm2 for dispersion slope. The standard deviation of zero dispersion wavelength is inverse proportional to the optical fiber lenght.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.9
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• pp.669-678
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• 2007

In this study, the ventilation characteristics is investigated numerically of the longitudinal ventilation method in the curved long road tunnel. Numerical work has been conducted for the jet fan location by utilizing the commercial finite-volume code, FLUENT. Configuration of the tunnel is three-lane, 1600 m long, $120m^2$ in area, 3000 m curvature radius. The velocity profile, distribution of mono-dioxide carbon and flow rate of air are examined in the tunnel. Through the analysis, it is found that the difference of ventilation flow rate Is a little by the jet fan location, but tunnel outlet setup (CASEIII) of jet fans is the most efficient concerned with CO concentration.