• 제목/요약/키워드: Small-signal

검색결과 2,289건 처리시간 0.037초

다중 바이어스 추출 기법을 이용한 HEMT 소신호 파라미터 추출 (Parameter Extraction of HEMT Small-Signal Equivalent Circuits Using Multi-Bias Extraction Technique)

  • 강보술;전만영;정윤하
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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    • pp.353-356
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    • 2000
  • Multi-bias parameter extraction technique for HEMT small signa] equivalent circuits is presented in this paper. The technique in this paper uses S-parameters measured at various bias points in the active region to construct one optimization problem, of which the vector of unknowns contains only a set of bias-independent elements. Tests are peformed on measured S-parameters of a pHEMT at 30 bias points. Results indicate that the calculated S-parameters is similar to the measured data.

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Implicit Restarted Arnoldi Method를 적용한 전력시스템 미소신호안정도 모델링 방법 연구 (A Study of Power System Modeling of Small-Signal Stability Using Implicit Restarted Arnoldi Method)

  • 김동준;문영환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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    • pp.217-219
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    • 2005
  • This paper describes implicit restated arnoldi method algorithm and Its application to small size power systems In order to observe the salient features of IRAM algorithm. Two area system with 36 state variables and England 39-bus system with 150 state variables have been tested using IRAM, and the eigenvalue results of IRAM are compared with those of the results obtained from QR method.

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광섬유 변위 센서를 이용한 미소 진동의 측정에 관한 연구 (Measurement of the small vibration using a fiber-optic displacement sensor)

  • 박우종;이혁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
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    • pp.353-355
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    • 1993
  • A single-mode fiber-optic interferometer for measuring small vibrations was constructed. The interferometer is based on the Fabry-Perot configuration that uses a single mode bidirectional fiber coupler as a beam splitter and employs peak detection scheme in the signal processing. The instrument was used to measure the displacement of the translator clamped to a piezo crystal.

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파형 분석을 위한 멕시코 모자 함수 응용 (Application of Mexican Hat Function to Wave Profile Detection)

  • 이희성;권순홍;이태일
    • 한국해양공학회지
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    • 제16권6호
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    • pp.32-36
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    • 2002
  • This paper presents the results of wave profile detection from video image using the Mexican hat function. The Mexican hat function has been extensively used in the field of signal processing to detect discontinuity in the images. The analysis was done on the numerical image and video images of waves that were taken in the small wave flume. The results show that the Mexican hat function is an excellent tool for wave profile detection.

압력 평형형 소형 베인펌프에서의 베인 이간 현상 측정 (The Measurement of Detachment of Vane Tip in a Positive Displacement Small Vane Pump)

  • 안형준;양광식;한동철;박민호
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1998년도 제28회 추계학술대회
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    • pp.365-370
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    • 1998
  • This paper reports on the measurement of the vane motion in a positive displacement small vane pump. The capacitive method using ceramic vane is proposed to measure the vane motion. This method enables us to measure only radial motion of the vane regardless of the motions of other directions. With simple experiments and solutions of simultaneous equations, the indirect compensation of measured signal was performed.

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간접 전파광의 수광 효율 향상에 관한 연구 (A Study on the Promotion of Indirect Light Receiving Efficiency)

  • 허수진;정찬수
    • 대한의용생체공학회:의공학회지
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    • 제13권3호
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    • pp.201-208
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    • 1992
  • In the indirect optical bio-telemetry, high frequency response and low minimum detectable optical power can be achieved by using photodiode with small light receiving area which minimizes junction capacitance. But, on the other hand, S/N ratio becomes low because the optical signal current is small. To solve such a problem, we attach plato-convex lens in front of photo diode, The results of comput- er simulation and experiments suggest promotion of light receiving efficiency and possibility of multi- telemetry system through directivity of convex lens in one room.

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미소변위 측정용 전기용량변환기 개발에 관한 연구 (A Study on the Development of Capacitive Transducer for Measurement of Small Displacement)

  • 박영태;이래덕
    • 대한전자공학회논문지
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    • 제24권5호
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    • pp.762-768
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    • 1987
  • The capacitive transducers, which are used of the principle of capacitance changes by means of the variation of distance between electrodes, are usually utilized for measurement of small displacements. But the measurement ranges of this method are limited. In this study, the measurement ranges are extended by using the variation method of the surface area of electrodes. Thus the capacitive transducer and signal conditioner, which are having the capability of measurement range of 25mm and resolution of 0.1\ulcorner, have developed, and its environmental characteristics are also tested.

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Identification of Small GTPases That Phosphorylate IRF3 through TBK1 Activation Using an Active Mutant Library Screen

  • Jae-Hyun Yu;Eun-Yi Moon;Jiyoon Kim;Ja Hyun Koo
    • Biomolecules & Therapeutics
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    • 제31권1호
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    • pp.48-58
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    • 2023
  • Interferon regulatory factor 3 (IRF3) integrates both immunological and non-immunological inputs to control cell survival and death. Small GTPases are versatile functional switches that lie on the very upstream in signal transduction pathways, of which duration of activation is very transient. The large number of homologous proteins and the requirement for site-directed mutagenesis have hindered attempts to investigate the link between small GTPases and IRF3. Here, we constructed a constitutively active mutant expression library for small GTPase expression using Gibson assembly cloning. Small-scale screening identified multiple GTPases capable of promoting IRF3 phosphorylation. Intriguingly, 27 of 152 GTPases, including ARF1, RHEB, RHEBL1, and RAN, were found to increase IRF3 phosphorylation. Unbiased screening enabled us to investigate the sequence-activity relationship between the GTPases and IRF3. We found that the regulation of IRF3 by small GTPases was dependent on TBK1. Our work reveals the significant contribution of GTPases in IRF3 signaling and the potential role of IRF3 in GTPase function, providing a novel therapeutic approach against diseases with GTPase overexpression or active mutations, such as cancer.

이동형 다목적실용위성 소형 관제국의 Playback 하향 링크 및 원격 명령 상향 링크 채널 설계 (Playback Downlink and Telecommand Uplink Channel Design for Transportable KOMPSAT Ground Station)

  • 안상일;박동철
    • 한국전자파학회논문지
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    • 제20권4호
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    • pp.396-405
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    • 2009
  • 본 논문은 이동 가능한 다목적실용위성의 소형 관제국 개발을 위한 playback 신호의 하향 링크 및 원격 명령 신호의 상향 링크에 대해 수행한 채널 설계를 기술한다. 하향 링크 패널 설계로서 playback 신호의 수신 임계 신호 대 잡음비로부터 요구 수신 성능을 도출하여 1.5 m 안테나 기반의 하향 링크 수신 성능인 6.5 dB/K의 G/T 이내에서 만족함을 확인하였다. 상향 링크 채널 설계를 통하여 원격 명령 신호에 대한 위성에서의 수신 신호대 잡음비로부터 40 dBW의 송신 EIRP를 유도하였다. 구축된 소형 관제국을 이용하여 다목적실용위성 및 다목적실용위성 2호에 대해 양 방향 통신시험 및 운영 결과, 고각 $10^{\circ}$ 이상에서 상향 링크 및 playback 신호의 하향링크 채널의 요구 성능이 일관성 있게 만족함을 확인하였고, 장기간에 걸친 시험 결과로부터 시스템의 성능 열화가 거의 없음을 확인함으로써 설계상으로 추가적인 3 dB 링크 마진을 고려하지 않은 소형 관제국의 채널 설계가 다목적실용위성에 대해 적절하였음을 검증하였다.

Blood Pulsation의 효과가 뇌 활성화에 미치는 영향을 알아보는 방법 (Estimation Method for Brain Activities are Influenced by Blood Pulsation Effect)

  • 이원호;구정훈;이형래;한기완;박진식;김재진;윤강준;김인영;김선일
    • 대한의용생체공학회:의공학회지
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    • 제28권3호
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    • pp.338-343
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    • 2007
  • BOLD T2*-weighted MR images reflects cortical blood flow and oxygenation alterations. fMRI study relies on the detection of localized changes in BOLD signal intensity. Since fMRI measures the very small modulations in BOLD signal intensity that occur during changes in brain activity, it is also very sensitive to small signal intensity variations caused by physiologic noise during the scan. Due to the complexity of movement of various organs associated with heart beat, it is important to reduce cardiac related noise rather than other physiological noise which could be required with relatively simple method. Therefore, a number of methods have been developed for the estimation and reduction of cardiac noise in fMRI study. But, each method has limitation. In this study, we proposed a new estimation method for brain activities influenced by blood pulsation effect using regression analysis with blood pulsation signal and the correspond slice of fMRI. We could find out that the right anterior cingulate cortex and right olfactory cortex and left olfactory cortex were largely influenced by blood pulsation effect for new method. These observed areas are mostly on the structure of anterior cerebral artery in the brain. That is convinced with that our method would be valid and our new method is easier to apply in practice and reduce computational burden than the retrospective method.