• 제목/요약/키워드: Fast response time

검색결과 839건 처리시간 0.039초

Development of a MEMS-based H2S Sensor with a High Detection Performance and Fast Response Time

  • Dong Geon Jung;Junyeop Lee;Dong Hyuk Jung;Won Oh Lee;Byeong Seo Park;Daewoong Jung
    • 센서학회지
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    • 제32권4호
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    • pp.207-212
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    • 2023
  • H2S is a toxic and harmful gas, even at concentrations as low as hundreds of parts per million; thus, developing an H2S sensor with excellent performance in terms of high response, good selectivity, and fast response time is important. In this study, an H2S sensor with a high response and fast response time, consisting of a sensing material (SnO2), an electrode, a temperature sensor, and a micro-heater, was developed using micro-electro-mechanical system technology. The developed H2S sensor with a micro-heater (circular type) has excellent H2S detection performance at low H2S concentrations (0-10 ppm), with quick response time (<16 s) and recovery time (<65 s). Therefore, we expect that the developed H2S sensor will be considered a promising candidate for protecting workers and the general population and for responding to tightened regulations.

A Fast Response Integrated Current-Sensing Circuit for Peak-Current-Mode Buck Regulator

  • Ha, Jung-Woo;Park, Byeong-Ha;Kong, Bai-Sun;Chun, Jung-Hoon
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제14권6호
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    • pp.810-817
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    • 2014
  • An on-chip current sensor with fast response time for the peak-current-mode buck regulator is proposed. The initial operating points of the peak current sensor are determined in advance by the valley current level, which is sensed by a valley current sensor. As a result, the proposed current sensor achieves a fast response time of less than 20 ns, and a sensing accuracy of over 90%. Applying the proposed current sensor, the peak-current-mode buck regulator for the mobile application is realized with an operating frequency of 2 MHz, an output voltage of 0.8 V, a maximum load current of 500 mA, and a peak efficiency of over 83%.

새로운 VA-$\pi$ cell mode cell mode를 이용한 광시야각 및 응답속도에 관한 연구 (Study of wide viewing angle and response time by using new VA-$\pi$ cell mode cell mode)

  • 이정호;김진호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.549-552
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    • 1999
  • We have developed an novel vertical-alignment (VA) - $\pi$ cell mode that provides a wide viewing angle and fast response times for negative dielectric anisotropy nematic liquid crystal (NLC) on a homeotropic polyimide (PI) surfaces. We had the good voltage-transmittance curves and low driving voltages were achieved with the novel VA - $\pi$ cell mode without negative compensation film. Iso-viewing angle characteristics using the novel VA - $\pi$ cell mode without negative compensation film of NLC was also successfully observed. As well a fast response time of 31.7ms for the novel VA - $\pi$ cell mode was measured. Consequently, It is seen that by using the novel VA - $\pi$ cell mode the iso-viewing angle, fast response time, and low driving voltage characteristics can be achieved.

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Fast Fringe-field-switching Liquid Crystal Cell with a Protrusion Structure

  • Park, Sung Il;Choi, Sun-Wook;Kim, Ki-Han;Song, Dong Han;Shim, Yu Ri;Lee, Sun Yong;Kang, Sung Gu;Yoon, Jeong Hwan;Kim, Byeong Koo;Yoon, Tae-Hoon
    • Journal of the Optical Society of Korea
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    • 제17권2호
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    • pp.200-204
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    • 2013
  • We propose a cell structure for the fast switching of liquid crystals by the fringe field. By forming protrusion between patterned electrodes, we can obtain enhancement of response time. The protrusion reduces the effective cell gap, with which a fast response time can be realized. There is little decrease in the transmittance because the protrusion is located between patterned electrodes. We confirmed that the total response time can be decreased by 33% with little loss of the transmittance by optimizing the shape of the protrusion structure.

고속응답 $CO_2$ 분석기의 제작 및 이를 이용한 SI 엔진에서의 실시간 배기가스 분석에 관한 연구 (Development of Fast-Response $CO_2$ Analyzer and Analysis of Engine-out Emission during Transient Condition of SI engine)

  • 송현수;민경덕
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.3079-3084
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    • 2008
  • A fast response $CO_2$ analyzer has been developed for measuring the $CO_2$ concentration during transient condition of SI engine. The analyzer is based on the non-dispersive infrared absorption technique, electrical chopping system and water cooling system. The analyzer has good repeatability, linearity and permissible drift characteristic. Besides, it has 18ms with a response to measure the $CO_2$ concentration. The fast response $CO_2$ analyzer was applied to single cylinder SI engine and the $CO_2$ emission was examined during engine start. Simultaneously, the standard exhaust gas analyzer, which has slow response time, was used for considering the engine-out $CO_2$ characteristic. The developed analyzer showed much faster responsive characteristic than that of a standard analyzer and made cycle by cycle exhaust gas analysis possible. The transient engine operating characteristics will be estimated and the transient behaviors on engine-out emission and performance will be improved.

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A Study on the Generalization of the Manabe Standard Forms with the Genetic Algorithm

  • Kang, Hwan-Il;Jung, Yo-Won
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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    • pp.116-120
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    • 1999
  • The step response of the Manabe standard form[1]has little overshoot and shows almost same waveforms regardless of the order of the characteristic polynomials. In some situations it is difficult to control the rise time and settling time simultaneously of the step response of the Manabe standard form. To control its rise time and settling time efficiently, we develop the generalization of the Manabe standard form: we try to find out the SRFS(Slow Rise time & Fast Settling time) form which has the slower rise time and faster settling time than those of the Manabe standard form. we also consider the other three forms: FRSS(Fast Rise time & Slow Settling time), SRFS(Slow Rise time & Fast Settling time) and SRSS(Slow Rise time & Slow Settling time) forms. In this paper, by using the genetic algorithm, we obtain all the coefficient of the four forms we mention above. Finally, we design a controller for a given plant so that the overall system has the performance that the rise time is faster, the settling time is slower than those of the Manabe standard form.

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The improvement of GTG response time using new concept LC mixture in S-IPS Mode for high frame frequency technologies

  • Kim, D.K.;Lim, C.S.;Lee, D.J.;Hwang, J.I.;Jung, H.G.;Lee, S.W.;Oh, C.H.;Kang, I.B.;Jin, Min-Ok;Jin, Heui-Seok;Lee, Seung-Eun;Jacob, Thomas;Czanta, Markus;Tarumi, Kazuaki
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.864-867
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    • 2006
  • In order to satisfy with the clear visibility without any difficulties such as blurring and tailing, the high refreshing rate technology and fast response time of LC itself were applied to TFT-LCDs. In proportion to the decrease of holding time of 1 frame, the fast transition of LC behavior was necessary to both maintain the luminance and minimize the tailing appearance. The introduction of a new LC mixture for faster response times was realized by the good combination of newly introduced dielectrically neutral LC material so called 'Super Low Viscosity' (SLV) and highly polar $CF_2O-linkage$ LC material. This resulted in about a 20% reduction in the ${\gamma}_1$ of the new LC mixture compared to the references. In accordance with a new LC mixture with low ${\gamma}_1$, fast response time of 5ms has been made for S-IPS LCD TV application. Consequently, by applying the high frame frequency of 120Hz driving alongside the 5ms response time characteristics, the MPRT value was reduced by half.

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폴리이미드 표면에서의 고속 TN 셀의 응답 특성 (Response Characteristics of Fast TN Cell on a Polyimide Surface)

  • 전용제;황정연;정연학;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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    • pp.514-517
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    • 2002
  • We investigated response characteristics of twisted nematic (TN) cell with different nematic liquid crystals (NLCs) and cell gap d on a rubbed polyimide (PI) surface. High transmittance and fast response time of the TN cell on the rubbed PI surface were achieved by using high birefringence (${\Delta}n$) and low cell gap d. The response time of TN cell on the rubbed PI surface was measured 5.1 ms. The transmittance and response time of the TN cell on the rubbed PI surface decreased with decreasing ${\Delta}nd$.

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In-plane Switching Liquid Crystal Cell with a Mixed Bent Electrode Structure for Fast Response Time

  • Ko, Tae-Woon;Kim, Jae-Chang;Lee, Joun-Ho;Choi, Hyun-Chul;Ji, Seung-Hoon;Choi, Jung-Min;Lee, Chul-Hun;Lee, Gi-Dong
    • Journal of Information Display
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    • 제9권3호
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    • pp.12-15
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    • 2008
  • A bent electrode structure is proposed in the super in-plane switching (S-IPS) liquid crystal (LC), as it can reduce the response time without loss of transmittance in the bright state. The electrode angle in each position of the bent electrode was optimized to simultaneously achieve high transmittance and fast response time. The electro-optical characteristics of the proposed LC cell structure were experimentally compared with those of the conventional cell. It was observed that the response time became over 8% shorter without loss of transmittance when the proposed bent structure was applied.

Novel Driving Method for fast Response Time in Vertical Alignment LCDs

  • Song, Jang-Kun;Jun, Man-Bok;Park, Bo-Yoon;Seomun, San-Seong;Lee, Kye-Hun;Choi, Kwang-Soo;Kim, Sang-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.205-208
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    • 2004
  • The switching mechanism of multi-domain vertical alignment mode LCD and delayed on response time phenomenon in special conditions are investigated. A modified DCC (Dynamic Capacitance Compensation), DCCII has been developed for the fast response time performance in PVA TFT-LCD TVs. DCCII applies a pre-tilt voltage to addressed pixels during the previous frame in addition to an overshoot voltage. In result, the response time less than 8 msec, has been obtained for all moving images through the DCCII technique.

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