• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.481-482
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• 2005

유기발광소자의 발광층의 전압에 따른 임피던스의 변화를 살펴보았다. 임피던스는 전압의 변화에 따른 의존성을 보이며, 그에 따른 임피던스와 Cole-Cole 반원의 변화를 전기전도기구와 비교하여 살펴보았다. 소자의 구조는 ITO/$Alq_3$/Al의 구조로 발광층의 두께는 60 nm로 열증착하여 실험하였다. 실험에서 전기전도기구의 Ohmic 영역, SCLC 영역, 부성저항영역, TCLC 영역에서 각각 임피던스를 측정하였고, 전압의 증가에 따라 임피던스의 크기가 감소하고, 위상각은 0V에서 용량성을 보이다가 발광영역에서 저항성을 나타내는 것을 알 수 있었다. 또한 전압에 따른 Cole-Cole 반원을 살며보면 전압이 증가할수록 반원의 크기가 감소하는 것을 알 수 있으며, 이를 통해 간단한 등가회로를 예측할 수 있었다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2006.11a
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• pp.185-188
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• 2006

생체 신경세포를 모방하는 진동성 신경 셀을 아날로그 집적회로로 설계한다. 진동성 신경셀은 입력신호 취합을 위한 취합회로와 신경 펄스 발생회로, 신경펄스 발생을 위한 범프회로와 트랜스콘덕터로 이루어지는 부성저항 블록으로 구성된다. $0.35{\mu}m$ 2중 폴리 공정 파라미터를 이용하여 SPICE 모의실험을 실시하여 입력 신호 유무 및 크기변화에 따른 출력 펄스의 발생을 얻어 진동성 신경회로의 가능성을 확인한다.

• Journal of the Semiconductor & Display Technology
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• v.18 no.2
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• pp.29-31
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• 2019

The ZTO/p-Si thin film was produced and investigated for tunneling phenomena caused by the interface characteristics of the depletion layer. ZTO thin film was deposited and heat treated to produce barrier potentials by the depletion layer. The negative resistance characteristics were shown in the thin film of ZTO heat treated at $100^{\circ}C$, and the insulation properties were the best. Current decreased in the negative voltage direction by nonlinear show key characteristics, and current decreased in tunneling phenomenon by negative resistance in the positive voltage direction. Heat treated at $100^{\circ}C$, the ZTO thin film has increased barrier potential in the areas of the depletion layer and therefore the current has increased rapidly. The current has decreased again as we go beyond the depletion layer. Therefore, tunneling can be seen to make insulation better. In the ZTO thin film heat treated at $70^{\circ}C$ without tunneling, leakage current occurred as current increased at positive voltage. Therefore, tunneling effects by negative resistance were found to enhance insulation properties electrically.

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.215-228
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• 2011

In the history, 'father' has been described as a being who not only take care of the family but also represents the family socially and supports them. Like the Western patriarchal tradition prevalent in the 19th century, fathers in Korean society also bear patriarchal paternity based on Korean traditional Confucian culture. In such a unique family culture of Korea, Korean fathers hold the patriarchal male centered idea and regard it as the roles of man and father to be responsible for the family's living and safety and to be more rational than emotional and more blunt than gentle. Social ideology for this image of father is expressed in media, and an example is the patriarchal image of father in TV dramas and movies. In order to analyze the image of Korean fathers described in films, this study selected two films and examined the semiological meanings of fathers' roles expressed in the films using Metz's syntagmatic and paradigmatic analysis method. The films chosen for case study are 'Fly Daddy', 'The Show Must Go On', and 'Speed Scandal'. These films are good examples demonstrating that Korean patriarchal paternity and its background traditional ideology are projected on media.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.10
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• pp.1131-1137
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• 2014

In this paper, oscillator with compact hairpin resonator is used to design the local oscillator of X-band radar system. The proposed hairpin resonator is minimized by increasing capacitance of line end of conventional one. By this method, size can be minimized about 40% compared with the conventional resonator and also can improve phase noise characteristic. The result of oscillator using proposed hairpin resonator is measured in oscillating frequency of 9.05 GHz, output power of 2.47 dBm, and phase noise of -101.4 dBc/Hz. The fabricated oscillator in this paper can minimize design and it's planar structure makes it easy to design MMIC.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.485-488
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• 2004

본 연구에서는 dipyridinium dithioacetate 분자를 Au(111) 표면에 자기조립하여 STM 탐침-유기 단분자막-Au(111)기판의 수직구조로 STM 측정시스템을 이용하여, 전기적 특성을 관찰하였다. 먼저 Au(111)기판을 Piranha용액$(H_2SO_4:H_2O_2=3:1)$으로 Au 표면을 전처리 하였다. 전처리한 Au(111) 기판을 dipyridinium dithioacetate 1mol/ml 농도로 자기조립 하였으며, 자기조립막의 표면 구조를 STM으로 관찰하였다. dipyridinium dithioacetate의 전기적 특성은 STM 탐침-유기단분자막-Au(111) 기판의 수직구조로 STS를 이용하여 조사하였다. 전압과 전류 측정에서 전압이 증가함에 따라 전류가 감소하는 부성 미분저항(NDR)의 특성이 관찰 되었다. NDR 수치가 $-545\;[m\Omega/cm^2]$였고, PVCR은 1.64:1 이었다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.4
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• pp.31-36
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• 1984

Various efforts have been dedicated to obtain the negative impedances in microwave frequencies with semiconductor devices by many scientists for f: some passed decades, and as a result, many solid state microwave devices have been developed. But they all have much less maximum power ratings with respect to the vaccum tubes. In this paper, a MOSFET is proposed and studied, which have a periodic structure of multigates on the semiconductor via insulator. The hish electric field in the channel induces a voltage distribution on the gates by electrostatic coupling, and the polarization so induced between the gates is able to give a space modulation of the velocity of carriers or the current density in the channel, and as a natural consequence, a microwave amplifier with higher power ratings can be expected.

• Journal of the Korean Institute of Telematics and Electronics
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• v.11 no.1
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• pp.40-46
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• 1974

This paper deals with the self-excited mixer using tunnel diode oscillator operated as a microwave source and Doppler signal detector. The system impedance, the oscillation condition and the frequency conversion theory including moving target are investigated. The oscillating frequency and the output of tunnel diode oscillator are 2.035 GHz and 0.1 mW. The input signal frequency which is equivalent to Doppler signal is lower than tunnel diode oscillator frequency by 125 MHz. TDe conversion loss has been investigated as a functicn of input signal level. This loss is greater than 67 db for the large pump mode.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.7
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• pp.729-736
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• 2011

In this paper, we propose a varactor-diodeless voltage-controlled oscillator operating at X-band, and verify the possibility of applying to a receiver for microwave radar signal detection applications. The proposed VCO is realized by only single RF BJT device as a varactor diode is substitued by a intrinsic collector-base PN-junction of the active device which is used to generate negative resistance. The fabricated VCO meets the specification of the receiver, which has a 11.20~11.75 GHz tuning bandwidth with respect to the tuning voltage, 1.0~7.0 V, output power of 9.0~12.0 dBm and linear frequency tuning performance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.3
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• pp.565-570
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• 2012

This paper has proposed a multi-channel low pass filter (LPF) for LTE-Advanced systems. The proposed LPF is an active-RC 5th chebyshev topology with three cut-off frequencies of 5 MHz, 10 MHz, and 40 MHz. A 3-bit tuning circuit has been adopted to prevent variations of each cut-off frequency from process, voltage, and temperature (PVT). To achieve a high cut-off frequency of 40 MHz, an operational amplifier used in the proposed filter has employed a PMOS cross-connection load with a negative impedance. A proposed filter has been implemented in a 0.13-${\mu}m$ CMOS technology and consumes 20.2 mW with a 1.2 V supply voltage.