• 제목/요약/키워드: Conjunction

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비드와 나선형 공진기를 이용한 전원 노이즈 저감 방안 연구 (Power Noise Suppression Methods Using Bead with Spiral Resonator)

  • 정동호;강희도;육종관
    • 한국전자파학회논문지
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    • 제24권2호
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    • pp.152-160
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    • 2013
  • 본 연구에서는 동시 스위칭에 의한 잡음 저감을 위하여 일반적으로 사용하는 비드와 더불어 나선형 공진기를 함께 사용하여 보다 향상된 광대역의 잡음 저감 특성을 확보하였다. 비드는 기본체배 주파수 아래 대역인 0.8 GHz 이내에서 효과적으로 잡음이 저감되고, 공진기는 공진기 턴 길이에 반비례한 공진 주파수 이내까지 잡음을 잘 저감할 수 있었다. 이것을 바탕으로 비드와 공진기를 함께 사용하면 각 주파수 영역에서 임피던스가 높은 성분에 의하여 영향을 받아 보다 광대역의 동시 스위칭에 의한 잡음 저감 특성을 얻을 수 있다. 22 nH 비드만을 사용한 경우 1, 2, 3, 그리고 4체배에서 각각 4.8, 2.0, 0, 0.6 dB의 노이즈 저감 특성을 얻었으나, 22 nH의 비드와 3턴 공진기를 함께 사용할 경우 9.5, 8.3, 6.1, 9.9 dB의 광대역에 걸친 잡음 감소 특성을 얻을 수 있었다. 비드가 없는 경우와 비교하여 22 nH 비드를 사용하면 전원단 흔들림이 76 mV에서 56 mV로 감소하고, 비드와 3턴 공진기를 함께 사용하면 34 mV로 감소함을 볼 수 있다. 즉, 비드와 공진기를 동시에 사용함으로써 보다 광대역의 동시 스위칭에 의한 잡음 저감 특성을 확보함을 보였다.

ON THE SHAPE DERIVATIVE IN THE DOMAIN INCLUSION

  • Kim, Hongchul
    • Korean Journal of Mathematics
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    • 제10권1호
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    • pp.75-87
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    • 2002
  • The shape derivative for the domain functional will be discussed in the situation of domain inclusion. Hadamard's shape structure is sought by using the material derivative in conjunction with the domain imbedding technique.

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Topics in TFT device physics and modelling

  • Migliorato, P.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.929-935
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    • 2005
  • This paper contains a review of methods to analise static and dynamic properties of trap states in TFTs. The Gap Density of States is extracted from C-V and I-V characteristics. Switch on transients and small signal ac measurements are used in conjunction with simulation and an analytic model to extract traps dynamic parameters.

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쌍안정 레이저 다이오드의 진행파형 모델 해석 (Travelling wave model analysis of absorptive bistable laser diode)

  • 서재원;박동욱
    • 한국광학회:학술대회논문집
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    • 한국광학회 2000년도 제11회 정기총회 및 00년 동계학술발표회 논문집
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    • pp.276.1-277
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    • 2000
  • Absorptive bistable laser diode was analyzed by using traveling wave model in conjunction with the finite-difference method. Carrier and photon density distributions were calculated and the output characteristics were obtained. The results for both the steady-state and transient (switching) cases were compared with those of the rate equation approach.

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Improvement of Active Homing Performance with Radome Slope Estimation in Spatial Engagements

  • Jin, Shin-Sang;Lyul, Song-Taek
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.64.3-64
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    • 2001
  • In this paper, an estimation scheme with the IMM algorithm to estimate radome slope and target states is used to reduce the radome induced miss distance effectively in spatial active homing engagements of an anti-air missile. The filter algorithm in conjunction with proportional navigation guidance is tested by a series of simulation runs.

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GaAs MESFET를 이용한 초고주파 증폭기에 관한 연구 (A Studyon Microwave Ampilifer using GaAs MESFET)

  • 박한규
    • 대한전자공학회논문지
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    • 제13권5호
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    • pp.1-8
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    • 1976
  • 게이트의 길이가 2mm인 GaAb 금속반도체전계치과트랜지스터를 HP8545 자동회로망분석기에 의하여 주파수 1∼2GHz 사이에서 산란계수를 측정하였고, 산란계수의 도움으로 완전한 등가회로를 구현하였다. 본 논문에서는 50Ω의 높은 입출력 Impedance로 정합시키기 위하여 Microstrip을 사용하여 GaAs MESFET증폭기를 개발하였으며 전력이득이 8dB, 정재파비가 1.5보다 적은 결과를 얻었다. Microwave GaAs Metal Semiconductor Field effect Transistors (MESFET) with the gate-length of two micrometers are investigated. The scattering parameters of the transistors have been measured from 1GHz to 2GHz by Hp8545 Automatic network analyzer. From the measured data, an equivalent circuit is established which consists of an ntrinsic and. extrinsic transistor elements. In this paper, GaAb MESFET Amplifier is used in conjunction with conventional microstrip techniques to match into a 50 ohms high input/output impedances system. We found that Power gain is less than 8dB and VSWR is less than 1.5 in L-Band.

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Strain elastography of palatal tumors in conjunction with intraoral ultrasonography, computed tomography, and magnetic resonance imaging: 2 case reports

  • Ogura, Ichiro;Toshima, Hiroo;Akashiba, Tohru;Ono, Junya;Okada, Yasuo
    • Imaging Science in Dentistry
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    • 제50권1호
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    • pp.73-79
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    • 2020
  • Computed tomography (CT) and magnetic resonance imaging (MRI) can be useful for the evaluation of palatal lesions, and strain elastography (performed together with intraoral ultrasonography) is a relatively new sonographic imaging modality. This report describes 2 clinical cases in which strain elastography was used to assess palatal tumors in conjunction with intraoral ultrasonography, CT, and MRI. In the first case, diagnosed as a myoepithelioma, the strain was determined to be 0.000% (strain of normal tissue, 0.556%). In the second case, diagnosed as an adenoid cystic carcinoma, the determined strain was 0.000% (strain of normal tissue, 1.077%). Therefore, we conclude that intraoral strain elastography can be useful for evaluating palatal lesions.

N-Nitrosamine과 단순포진성 바이러스가 햄스터의 구강암발생에 미치는 영향에 관한 실험적 연구 (Combined Effect of N-Nitrosamines and Herpes Simplex Virus on Oral Carcinogenesis in Hamsters)

  • JP Hong
    • Journal of Oral Medicine and Pain
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    • 제15권1호
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    • pp.125-132
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    • 1991
  • We have previously reported that simulated snuff dipping in conjunction with type I herpes simplex virus (HSV-1) induced oral malignant changes in hamsters. Present study was designed to investigate the carcinogenic effect of tobacco specific-N-nitrosamines (TSNAs) and HSV-1, alone or in combination, in hamsters. Hamsters were divided into 6 groups and the right buccal pouch mucosa were treated as follows: Grp 1, Control (Mock inoculation) [MI]+Topical Application [TA] of mineral oil[MO] : Grp 2, TA of 1% n'- nitrosonornicotine [NNN] + IM: Grp3, TA of 1% 4-N-nitrosomethylamino-1- (3-pyridyl)-1-butanone [NNK] + MI: Grp 4, HSV-1 inoculation [HI]+TA of MO : Grp 5, TA of 1% N-nitrosonornicotine [NNN] + HI: Grp 6, TA of 1% NNK + HI. TA of MO or TSNAs was initiated 1 day after the MI or HI and given 3 times per week for 20 consecutive weeks. At the buccal pouches were fixed for light microscope examination. No animal s developed tumors or malignant histopathologic changes in the mucosa of the buccal pouches. These data indicate that individual TSNAs, alone or in conjunction with HSV-1 infection, do not develop malignant changes in hamster buccal pouches.

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