• 전자공학회논문지D
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• 제34D권10호
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• pp.14-23
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• 1997

An MMIC downconverting mixer for cellular phone application has been successfully developed using an MMIC process including $1 \mu\textrm{m}$ ion implanted gaAs MESFET and passive lumped elements consisting of spiral inductor, $Si_3N_4$ MIM capacitor and NiCr resistor. The configuration of the mixer presented in this paper is single-ended dual-gate FET mixer with common-source self-bias circuits for single power supply operation. The dimension of the fabricated circuit is $1.4 mm \times 1.03 mm $ including all input matching circuits and a mixing circuit. The conversion gian and noise figure of the mixer at LO powr of 0 dBm are 5.5dB and 19dB, respectively. The two-tone IM3 characteristics are also measured, showing -60dBc at RF power of -30dBm. Allisolations between each port show better than 20dB.

• 한국공작기계학회논문집
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• 제13권5호
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• pp.16-23
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• 2004

The wear behavior as the hardness of the sliding elements on the dry wear has been investigated using a disc on disc configuration. The materials of the specimens are used as ten kinds along their hardness. In this study, both upper and lower specimens have been used the same materials. Using experimental data, we figured the relationship between wear coefficient and friction coefficient, and the relationship between wear coefficient and friction temperature. Also we combined friction temperature and friction coefficient instead of wear coefficient. We substituted this into wear equation of Archard. The result had been derived a newly wear equation in disc on disc wear system.

• 한국광학회지
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• 제15권3호
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• pp.274-277
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• 2004

본 논문에서는 두 개의 중첩된 Mach-Zehnder 구조의 변조기를 이용한 집적광학형 RF 위상변환기를 제안하고, 새로운 전기광학폴리머를 이용하여 제작하였다. 구현된 소자는 RF신호의 위상을 전압에 의하여 연속적으로 제어할 수 있는 특징을 갖는다. 본 논문에서는 16 GHz RF신호의 경우에 대해, 7.8 $V_{pp}$ 제어 전압을 인가하여 약 108$^{\circ}$범위에서 RF신호의 위상을 거의 선형적으로 변환시킬 수 있었다.다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.441-444
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• 2002

If an antiferroelectric liquid crystal (AFLC) cell is set between crossed polarizers for optical modulators or displays, it has low transmittance efficiency. This happens because AFLC materials have inherent tilt angles of typically $18^{\circ}{\sim}38^{\circ}$, not $45^{\circ}$. To improve the low transmittance efficiency, we propose a new optical configuration for antiferroelectric liquid crystal displays, which also improves color dispersion.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.496-499
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• 2007

The COMS ground segment will operate the geostationary satellite continuously 24h/7days and deliver processed data to end-users with respect to the predefined schedule without delay. For reliable operation, each COMS ground center has internally dual-configuration for critical systems but impossible to every components. Any unexpected failure or regular maintenance to the single configured antenna system may lead the interruption of COMS service and operation. The natural disaster or external attack can destroy one ground center and the operation will be stopped. Therefore COMS program implements backup system remotely located in other centers. Even considering foreign geostationary systems, it's the best solution guaranteeing consistent system operation against internal failure or external disaster.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3721-3737
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• 2015

3D reconstruction based on binocular data is significant to machine vision. In our method, we propose a new and high efficiency 3D reconstruction approach by using a consumer camera aiming to: 1) address the configuration problem of dual camera in the binocular reconstruction system; 2) address stereo matching can hardly be done well problem in both time computing and precision. The kernel feature is firstly proposed in calibration stage to rectify the epipolar. Then, we segment the objects in the camera into background and foreground, for which system obtains the disparity by different method: local window matching and kernel feature-based matching. Extensive experiments demonstrate our proposed algorithm represents accurate 3D model.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.44-46
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• 2008

Air-breathing polymer electrolyte membrane fuel cells (PEMFC) are highly promising particularly for small-power applications up to tens watts class. A distinctive feature of the air-breathing PEMFC is its simple system configuration in which axial fans operate for dual purposes, supplying both oxidant and coolant in a single manner. In the present study, a nominal 80W air-breathing PEMFC system is developed and investigated to determine the optimal operating strategy through parametric studies (i.e., reactant humidity, and fanblowing flow rate). The cell voltage distributions are examined as a function of time to evaluate the system performance under various operating conditions.

• 전기학회논문지
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• 제65권3호
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• pp.452-456
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• 2016

In this paper, a dual-channel readout amplifier array is realized in a standard $0.18{\mu}m$ CMOS technology for the applications of panoramic scan LADAR systems. Each channel consists of a PIN photodiode with 0.9 A/W responsivity and a 1.0 Gb/s readout amplifier(ROA). The proposed ROA shares the basic configuration of the previously reported feedforward TIA, except that it exploits a replica input to exclude a low pass filter(LPF), thus reducing chip area and improving integration level, and to efficiently reject common-mode noises. Measured results demonstrate that each channel achieves $70dB{\Omega}$ transimpedance gain, 829 MHz bandwidth, -22 dBm sensitivity for $10^{-9}BER$, -34 dB crosstalk between adjacent channels, and 45 mW power dissipation from a single 1.8 V supply.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.509-515
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• 2002

While performing the advisory services of the electrification of conventional lines for KTX(Korea High Speed Train), we faced the speed-up problem of catenary system for the existing narrow tunnel. To solve this problem, the new system, to be named "Oblique encumbrance tunnel catenary", was developed. This system is mainly characterized by a simple catenary type, a dual bracket, a oblique encumbrance, a small system height and the same bracket used for the radial tension load and compression one. In this paper, the basic concepts, overall system configuration and main points considered in a design phase for the ′oblique encumbrance tunnel catenary′ are described. Moreover, the detail design criteria and other contents like manufacturing pilot products and verifying the performance through a factory and site test are added.

• 제어로봇시스템학회논문지
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• 제12권9호
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• pp.918-925
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• 2006

Medical robotics and computer aided surgery in general, and robotic telesurgery in particular, are promising applications of robotics. In this paper, we shows a novel single-master (PHANTOM based single-master multi-slave telerobotic system) multi-slave system using two parallel mechanism micromanipulators as a slave device. After a general introduction to the systems structure and configuration of telerobotic system, a manipulation control strategy to build the system that human and both manipulators perform the cooperative manipulation, is introduced, followed by its kinematic analysis, mapping method, and experimental results.