• 전자공학회논문지 IE
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• v.48 no.3
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• pp.10-15
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• 2011

In the case of designing an acoustic transducer for high power application, we usually aim to transfer the source electric energy to the output acoustic energy as large as possible. For this purpose, we should match the impedance of the power amplifier to the impedance combined with the acoustic transducer impedance and the radiation impedance. Especially if we have electrical source with almost zero impedance, we need improve the power factor of the acoustic transducer in the load. In this paper, we propose a broad band impedance matching method by the improvement of power factor, which applies ABCD matrix.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.13 no.1
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• pp.48-53
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• 2017

We diagnosed the defect using the data obtained from the nuclear power plant simulator. In this paper, we diagnosed faults in the nuclear power plant system for discovery instead of the traditional single-component or device unit. We created the six fault scenarios and used a fault simulator to obtain the fault data. It was extracted pattern from acquired failure data. Neural network model was trained and simple pattern matching algorithm was applied. We presented a simulation result and confirmed that the applied algorithm works correctly.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.193-194
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• 2007

This paper presents the design of a power amplifier for full-band UWB application systems using a CMOS 0..18um technology. A wideband RLC filter and a multilevel RLC matching scheme are utilized to achieve the wideband input/output matching. Both the cascade and cascode stage are used to increase the gain and to achieve gain flatness. Simulation results show that the designed amplifier provides a power gain greater than 10 dB throughout the UWB full-band(3.1-10.6GHz) and an input P1dB of -1.2dBm at 6.9GHz. It consumes 35.8mW from a 1.8V supply.

• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.60-64
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• 1997

The design process and construction method of a strip line is described for measuring radiated susceptibility of vehicular components having electrical cables more than 2 min length. he characteristic impedance of the trip line was determined 90$\Omega$ to obtain the field uniformity of $\leq$${\pm}$3 dB in the frequency range from 100 kHz to 500 MHz. Tapered coaxial lines were used instead of the traditional lumped circuit element for the impedence matching units, therefore, the strip line has high power capability. Using these techniques, the field uniformity and power capability of a strip line could be considerably improved.

• Journal of the Korean Ceramic Society
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• v.47 no.5
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• pp.430-432
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• 2010

We verified through a noncritical phase-matched second-harmonic generation experiment that the periodically-poled $LiNbO_3$ (PPLN) had a large effective nonlinear optical coefficient, demonstrating that the QPM grating was uniform throughout the entire length of PPLN. The quasi-phase matching temperature was $193.4^{\circ}C$. The maximum SHG output power at the fundamental power of 2.0 W was found to be 18.0 mW; generated second-harmonic beam was found to have no photorefractive effect.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.445-446
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• 2012

Recently the interest in wireless power transfer have been studied. ECR (Electromagnetic Coupled Resonance) device, depending on the size of the frequency characteristics of the structure, increasing in volume and larger volume of wireless power transmission device to make use of ECR is a big barrier. So to solve this problem for ECR device miniaturization and high efficiency has been actively studied. In this paper, the size of the device for ECR IM (Impedance Matching) by applying a one-turn coil circuit, remove the device in the form of ECR Network Analyzer measured by removing the one-turn coil has demonstrated the possibility of the device in the form of ECR.

• Journal of IKEEE
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• v.23 no.2
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• pp.403-406
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• 2019

We propose a low-loss on-chip transformer using an auxiliary primary part (APP) for an output matching network for fully integrated CMOS power amplifiers. The APP is designed using a fifth metal layer while the primary and secondary parts are designed using a sixth metal layer with a width smaller than that of the primary and secondary parts of the transformer to minimize the substrate loss and the parasitic capacitance between the primary and secondary parts. By adapting the APP in the on-chip transformer, we obtain an improved maximum available gain value without the need for any additional chip area. The feasibility of the proposed APP structure is successfully verified.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2389-2392
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• 2005

We present fast stereo matching algorithm using edge projection. Traditional stereo matching algorithm uses 2D template for the search of corresponding point thus it requires huge the computational cost. In this paper, we reduce the 2D search problem into 1D using edge projection along vertical and horizontal direction inside the region of interest. Also, by accumulation of edge projection along vertical and horizontal direction, the edge projection within the region of interest could simply be obtained by just subtracting two values. Experimental results show that matching algorithm using edge projection also gives comparable discriminating power compared to that of using intensity.

• The Korean Journal of Ceramics
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• v.6 no.3
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• pp.206-208
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• 2000

0.65 mol% MgO-doped LiNbO$_3$single crystals were grown by CZ method. The obtained single crystals were colorless and transparent. Noncritically phase-matched second harmonic generation (SHG) of 532-nm radiation from 1064-nm in MgO-doped LiNbO$_3$has been investigated by using pulsed Nd:YAG laser. The phase-matching temperature was room temperature. SHG conversion efficiencies were typically achieved higher than 50% at the phase-matching temperature with no photorefractive damage in the region of fundamental power density which was used in this experiment. The thermo-birefringence coefficient and the electro-birefringence coefficient of SHG were calculated from the temperature phase-matching profile with the electric field.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3314-3318
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• 2021

This paper presents a mode-matching analysis of the electromagnetic coupling between open cable trays in an indoor structure when an electric-line current is generated as an electromagnetic source. We validated the mode-matching method by comparing the mode-matching results with those computed from a commercial electromagnetic simulator and then investigated the strength of the electric-field coupled in a victim cable tray while varying the distances between cable trays and architectural surfaces. The results of this study provide geometrical information on the placement of open cable trays to avoid electromagnetic interference problems.