• 제목/요약/키워드: negative feedback

검색결과 465건 처리시간 0.029초

연산증폭기의 고조파 왜곡 개선에 관한 연구 (A Study on the Improved of the Harmonic Distortion of the Operational Amplifier)

  • 정종혁;양규직
    • 한국항해학회지
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    • 제20권3호
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    • pp.117-126
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    • 1996
  • Generally, the distortion of the negative feedback amplifier is reduced by a factor equal to the return difference (1+${\beta}_1A_1$), but the proposed feedforward amplifier is reduced by a factor equal to the square of the return difference (1+${\beta}_1A_1$). In this paper, a feedforward amplifier with error correction is designed and implemented. So as to evaluate the characteristics of the harmonic distortion that the inverting feedforward amplifier is compared with that of the reference amplifier without feedforward error correction. It is confirmed that the proposed method should be able to reduce much greater than compared with a conventional negative feedback amplifier. Therefore it should be noted that the proposed feedforward amplifier network is also acceptable for wide-band amplifiers and the network which is demanded to improve the harmonic distortion.

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저전압 능동 인덕터 VCO를 이용한 주파수 합성기 (A Frequency Synthesizer using Low Voltage Active Inductor VCO)

  • 이순재;이동건;정항근
    • 전기학회논문지
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    • 제59권2호
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    • pp.471-475
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    • 2010
  • This paper presents a frequency synthesizer using low voltage active inductor VCO(Voltage Controlled Oscillator). The low voltage active inductor VCO with feedback resistor increases its equivalent inductance and the quality-factor(Q). Under certain conditions, the low voltage active inductor with feedback resistor generates a negative resistance at the input. In this paper, the conditions for negative resistance are obtained by small signal analysis. The designed low voltage active inductor VCO covers a frequency band between 1059MHz and 1223MHz. The measured phase noise at 1.178GHz is -81.8dBc/Hz at 1MHz offset.

A High-Speed and High-Accurate Common Source Type Analog Buffer Circuit Using LTPS TFTs for TFT-LCDs

  • Kim, Hyun-Wook;Byun, Chun-Won;Kwon, Oh-Kyong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.829-832
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    • 2007
  • A high-speed and accurate analog buffer is proposed for mobile display using LTPS TFTs. The proposed analog buffer is common source type with sampling and negative feedback mode. Therefore, driving speed of the proposed buffer is faster than previously reported one. In addition, the accuracy is very high because of high negative feedback gain. The simulation results show that maximum mischarging voltage of the proposed buffer is 8mV and previously reported one is 37mV. And Power consumption of the proposed buffer is $43.1{\mu}W$, which is 73% of previously reported one.

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고정이득 궤환 안정화를 위한 충분조건 (A Sufficient condition for constant gain feedback stabilization)

  • Kang, Hwan-Il
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.1167-1170
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    • 1999
  • We consider a negative unity feedback control system in which a controller and a given minimum phase transfer function are in cascade. This paper present a sufficient condition for the existence of a constant gain controller under which the overall closed loop characteristic polynomial is stable. This sufficient condition is based on Lehnigk's lemmas.

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벅형 프리레귤레이터를 가진 일정주파수 직렬공진변환기를 위한 새로운 준최적제어기 설계 (A sub-optimal controller design for constant-frequency series resonant converter with buck type pre-regulator)

  • 안희욱;고정호;윤명중
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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    • pp.96-100
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    • 1990
  • Dynamic modelling and controller design technique for constant-frequency series resonant converter with buck type preregulator are mainly described in this paper. An equivalent circuit model is derived and a state equation is developed from this model. To improve the dynamic performance, a negative feedback of inductor current is added to the proportional and integral control of output voltage. Furthermore, an optimization technique with prescribed eigenvalue region is applied to the determination of feedback gains. With the presented design method, much better dynamic performance can be obtained.

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광전궤환을 이용한 짧은 광펄스 생성 (Generation of Optical Short Pulses with Optoelectronic Feedback)

  • 이창희;조건호;이성호;신상영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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    • pp.477-479
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    • 1988
  • A new method of optical short pulse generation using stable diode lasers with negative optoelectronic feedback is demonstrated experimentally. About 1 nanosecond pulses with 300 MHz repetition rate are generated.

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직무특성이 점진적 혁신에 미치는 효과 및 재직 기간의 조절효과 (The relationship between job characteristics and incremental innovation, and the moderating effect of tenure)

  • 안관영
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2011년도 춘계학술대회
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    • pp.19-28
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    • 2011
  • This paper reviewed the relationship between job characteristics and incremental innovation, and the moderating effect of tenure. The results of multiple regression analysis, based on the responses from 241 employees in service industry, showed that job variety, identity, importance, autonomy and feedback have positive relationships with incremental innovation. In moderating effects, tenure interacts with variety and identity to have positive effects on incremental innovation, but tenure interacts with job importance, autonomy and feedback to have negative effects on incremental innovation.

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The Effect of Performance Feedback on Firms' Decision to Form an International Strategic Alliance and Performance in the Korean Manufacturing Industry

  • Han, Sang-yun
    • Journal of Korea Trade
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    • 제25권6호
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    • pp.57-77
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    • 2021
  • Purpose - International strategic alliance has been regarded as a strategic decision made by firms' managerial problems and ensure performance growth. From the perspective of the proactive behavior for changing strategies in a global market, this study aims to identify whether performance feedback influences firms' decisions to pursue strategic alliances. This study examines the effects of performance feedback on performance when firms use strategic alliances. Design/methodology - To analyze the impact of performance feedback on forming an international strategic alliance, this study adopt the concept of performance feedback to develop a research model and our hypotheses. Thus, this study used a two-stage least squares unbalanced panel data analysis with random effects. This study is based on 24,543 observations from Korean manufacturing firms from 2007 to 2016. Findings - The results show that firms pursue the formation of strategic alliances more actively, if their past financial and R&D performance are lower than their aspiration level, based on the result of performance feedback. An in split sample analysis for examining the effect of a firm's technology sophistication based on the OECD's classification, negative innovation performance discrepancy has positive effects on the probability of international alliance in high-tech and medium-high-tech industries. Financial performance also improves when a firm decides to form a strategic alliance based on the results of performance feedback. Originality/value - This research extends recent efforts to better understand the effect of performance feedback on firms' performance when they use strategic alliances. These findings suggest that the CEOs and managers of firms should consider the performance feedback perspective when deciding to pursue a strategic alliance to improve performance. In other words, the decision-makers in a firm must analyze and consider various complex variables inside and outside the firm and expand such subjects of examination to more complex and dynamic factors.

H.263에 적합한 개선된 에러 트래킹 알고리즘 (Advanced Error Tracking Algorithm for H.263)

  • Hyo-seok Lee;Soo-Mok Jung
    • 한국컴퓨터산업학회논문지
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    • 제5권1호
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    • pp.123-130
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    • 2004
  • 본 논문에서는 피드백 채널을 사용하여 error resilient transmission에 적합한 개선된 에러 트래킹 알고리즘을 제안하였다. 오염된 블록들의 주소는 디코더에 의하여 인코더에게 보고 된다. 제안된 알고리즘을 사용하여 에러 전파를 줄였다. 인코더는 피드백 채널의 negative acknowledgement를 가지고 역방향 움직임 의존도를 조사하여 전파된 에러를 현재 인코딩 되는 프레임 내에서 정확하게 추적한다. 제안된 에러 트래킹 알고리즘을 사용하여 영향을 받은 매크로 블록을 INTRA 코딩함으로 에러 전파효과를 완전히 종식시킬 수 있다. 선택적으로 네 모서리 에러 트래킹 근사를 사용하는 제안된 알고리즘의 에러트래킹 연산량은 전체 픽셀을 사용한 경우의 에러트래킹의 연산량에 비하여 매우 적으나 영상의 질은 동일하게 유지된다.

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정보보안 준수에 부정적 영향을 미치는 걱정 완화에 대한 연구 (A Study on the Mitigation of Anxiety that Negatively Affect Information Security Compliance)

  • 황인호
    • 한국콘텐츠학회논문지
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    • 제21권4호
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    • pp.153-165
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    • 2021
  • 연구 목적은 조직 구성원의 정보보안 준수의도에 긍정적, 부정적 영향을 주는 선행요인을 찾는 것이다. 세부적으로, 연구는 준수의도에 부정적 영향을 미치는 걱정을 감소시키기 위한 선행 요인을 찾고, 걱정과 준수의도간의 부정적 관계를 피드백이 조절하는 것을 확인하고자 한다. 설문 대상은 정보보안 정책을 보유한 조직에 근무하는 직장인을 대상으로 하였으며, 구조방정식모델링을 기반으로 주효과 분석과 조절효과 분석을 실시한다. 연구 결과, 걱정은 준수의도에 부정적 영향을 미쳤으며, 경영진의 지원을 통해 높아진 조직문화가 걱정을 감소시키는 것을 확인하였다. 또한, 피드백이 걱정과 준수의도간의 부정적 영향 관계를 조절하는 것을 확인하였다. 연구의 시사점은 정보보안 기술 도입을 통해 발생한 걱정의 부정적 영향을 찾았고, 걱정을 완화하기 위한 방안을 제시하였다. 즉, 연구는 조직 내부의 정보보안 수준 향상을 위해 고려해야 할 전략 방향을 제시한다.