• Journal of the Institute of Electronics Engineers of Korea TC
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• 제39권12호
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• pp.559-565
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• 2002

Today, because a quality factor of the inductor fabricated on silicon substrate for RFIC is under 12, the realization of inductor haying high-Q is essential. In this paper, two inductors having improved Q-factor are proposed and fabricated using a bondwire on silicon substrate. Also for the PGS is applied to the same inductors, four inductors are fabricated finally The bondwire Inductors have the relatively low conductor loss due to wide cross-section area and they can reduce the parastic capacitance very much because they are located in the air. Simulation and measurement results show that the proposed inductors have much more improved Q-factor, 15, than a conventional spiral inductor at 1.5 GHz. Because of the use of an automatic bonding machine, we can fabricate the high - Q inductors very easily, repeatedly.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제19권3호
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• pp.311-320
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• 2008

In this paper, a new variable active inductor using a conventional grounded active inductor with feedback variable LC-resonator is proposed. The grounded active inductor is realized by the gyrator-C topology and the variable LC-resonator is realized by the low-Q spiral inductor and varactor. This variable LC-resonator can compensate the degradation of Q-factor due to parasitic capacitance of a transistor, and the frequency range with high Q-factor is adjustable by resonance frequency adjustment of LC-resonator. The fabricated variable active inductor with Magnachip $0.18{\mu}m$ CMOS process shows that high-Q frequency range can be adjusted according to varactor control voltage from 4.66 GHz to 5.45 GHz and Q-factor is higher than 50 in the operating frequency ranges. The measured inductance at 4.9GHz can be controlled from 4.12 nH to 5.97 nH by control voltage.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제22권7호
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• pp.1015-1020
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• 2018

The cavity resonator is one of the widely used components in the microwave applications. The unloaded Q, the resonant frequency, and the coupling factor are basic parameters of a cavity. A simple unloaded Q factor measurement procedure of a cavity is proposed in a lossy coupling. The equivalent circuit of a cavity with coupling loss at near the resonant frequency is presented. The coupling loss resistance was found by the measurement of a cavity impedance. The cavity impedance compensated coupling loss was redrawn on the Smith Chart. The loaded Q and coupling factor were obtained based on the compensated impedance locus and then the unloaded Q factor was calculated. To verify the proposed procedure, the cavity with lossless coupling was measured. The two measurement results in the lossy and lossless coupling agree well. The results confirm the proposed procedure is valid.

• Journal of the Institute of Electronics Engineers of Korea SD
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• 제45권2호
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• pp.125-129
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• 2008

A low-voltage active CMOS inductor approach, which can improve the quality-factor(Q), is proposed in this paper. A low-voltage active inductor circuit topology with a feedback resistance is proposed, which can substantially improve its equivalent inductance and quality-factor(Q). This proposed low-voltage active inductor with a feedback resistance was simulated by ADS(Agilent) using 0.18um standard CMOS technology. Simulation showed that the designed active inductor had a maximum quality-factor(Q) of 3000 with a 1.5nH inductance at 4GHz

• Journal of the Korea Society of Computer and Information
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• 제29권2호
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• pp.169-177
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• 2024

The purpose of this paper is to explore the meaning of talent donations by semi-professional Athlete using Q methodology. This Q factor analysis finally identified 3 factors: The first factor, The type of donation cautious, They represent an understanding the need for donation, needing to prepare for donation, information about donation targets, careful attitude toward talent donation. The second factor, The type of donation authenticity, They represent departure from good mind, premise of authenticity to donation, necessity of program for donation activities. The final factor, The type of trust for endowment institution, They represent trust in the target organization to donate, interest in donation-related incidents, necessity of various donation methods in sports field.

• Journal of Sensor Science and Technology
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• 제33권1호
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• pp.1-6
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• 2024

This study aims to suggest the partition ratio (Q-factor) of healthy Koreans and the comparison results of breath alcohol concentration (BAC) measurements using two methods (photoacoustic and electrochemical methods) for developing breath alcohol ignition interlock devices (BAIIDs). Given the relationship between BACs and BrACs and the Q-factor, the alcohol metabolism of healthy Koreans (96 males and 91 females) is revealed for understanding the digestion of alcohol and surveying the fundamental data of alcohol-related problems, CO₂ concentrations vs. alcohol concentrations, and the performance of alcohol sensors in the marketplace. The average Q-factor of healthy Korean males and females are 1,913 (95% confidence interval from 1,889-1,937) and 1,991 (95% confidence interval from 1,945-2,036). Photoacoustic measurements could be applied to predict the BACs of drinkers, which is confirmed by the Bland-Altman plots presented in this study. The biases based on the partition ratios (Q=1,913 and Q=1,991) in the Bland-Altman plots were -0.0004% (95% CI from -0.0011 to +0.0003% for males) and -0.0017% (95% CI from -0.020 to +0.017% for females).

• Journal of Advanced Navigation Technology
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• 제19권3호
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• pp.244-249
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• 2015

High-altitude electromagnetic pulse (HEMP) is generated from a nuclear burst at high altitudes above the Earth, the electromagnetic fields reach the ground nearly simultaneously with regard to the operation time of systems. The aim of this analysis is to inquire about HEMP characteristics and to analyze about effect in orthogonal frequency division multiplexing (OFDM) system. Specifically, HEMP characteristics are classified field sources, spatial coverage, time domain behavior, frequency spectrum and field intensities in this study. Bits error rate (BER) of the receiver with the software simulation is confirmed for the HEMP effect. Q-factor made a difference about interference duration by transfer characteristics of system. When Q factor is smaller, the recovery time from HEMP interference is short. To the contrary, if the Q factor is larger, the recovery duration is lasted longer by 300-600%.

• Proceedings of the KIEE Conference
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2205_2206
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• 2009

Decoupling capacitor는 Power Plane의 특정 주파수 대역에서 Anti-resonance가 발생, 전력 전달에 저해가 될 시에 부착되어 원활한 전력전달을 하기위한 도구로 많이 사용되어 왔다. 하지만 De-cap(Decoupling capacitor)을 어느 위치에 어떤 용량으로 부착하여야 하는지 문제점이 제기되고 이를 해결하기 위해 무작정 설치하여 보는 번거로움이 있었다. 본 문에서는 De-cap의 적절한 사용법에 대한 방법과 Q-factor의 적용법을 제시한다.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 한국전자파학회 2000년도 종합학술발표회 논문집 Vol.10 No.1
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• pp.243-247
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• 2000

In this parer, Q-factor measurement method for a dielectric resonator in an MIC environment using the effective dielectric constant is proposed. The effective dielectric constant technique is applied to both radial and axial directions. The proposed method shows that the accuracy of the Q-factor measurement is to be improved with 2% ～ 3% relative error.

• Proceedings of the Korean Vacuum Society Conference
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.559-559
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• 2012

We developed a new scheme for the highly sensitive near-field scanning optical microscope (NSOM) by using a dithering sample stage rather than a dithering probe. In the proposed scheme, the sample is directly loaded on one prong surface of a dithering bare tuning fork. Gap control between probe and sample is performed by detecting the shear force between an immobile fiber probe and the dithering sample. In a conventional NSOM, the Q factor drastically decreases from 7783 to 1000 or even to 100 by attaching a probe to the tuning fork. In our proposed NSOM, on the contrary, the Q factor does not change significantly, 7783 to 7480, when the sample is loaded directly to the tuning fork instead of attaching a probe. Consequently, the graphene sheets that cannot be observed by a conventional NSOM were clearly observed by the proposed method with sub-nanometer vertical resolution due to the extremely high Q factor.