• 제목/요약/키워드: Sensor Sensitivity

검색결과 1,892건 처리시간 0.03초

Application of DFB Diode Laser Sensor to Reacting Flow (I) - Estimation and Application to Laminar Flames -

  • Park, Gyung-Min;Masashi Katsuki;Kim, Duck-Jool
    • Journal of Mechanical Science and Technology
    • /
    • 제16권11호
    • /
    • pp.1550-1557
    • /
    • 2002
  • Diode laser sensor for measuring gas temperature and species concentration in combustion chamber was developed using 2.0 tim distributed feed back lasers. To evaluate the measurement sensitivity of diode laser sensor system, CO2 survey spectra near 2.0 Um were measured and compared with the calculated one. This diode laser absorption sensor was applied to measure gas temperatures in a premixed flat flame of CH$_4$-air mixture. Experimental results were in good agreement with the values by an R-type thermocouple within 6.12%. In addition, successful demonstration of measurement of gas temperature and species concentration in a soot flame showed the promising possibility of diode laser absorption sensors for practical combustion system with non-intrusive method.

고정도 광 전류센서 구현을 위한 파라미터 분석 연구 (A Study on the Parameter Analysis for High Precision Optical Current Sensor Implementation)

  • 김영수;임용훈;현덕화
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.265-267
    • /
    • 2001
  • In this paper, some optical parameters which have effects on the measuring precision and sensitivity of optical current sensor are analyzed. Each parameter occurs changes of specific characteristics of optical sensor system. The influences of performance and characteristics variation of optical current sensor are described in accordance with the changes of optical output power, optical bias point which is called phase difference, and a specific constant related to sensor material and wavelength of light source.

  • PDF

수직속도 기반 충격전 낙상 감지에 관한 연구 (Study on Vertical Velocity-Based Pre-Impact Fall Detection)

  • 이정근
    • 센서학회지
    • /
    • 제23권4호
    • /
    • pp.251-258
    • /
    • 2014
  • While the feasibility of vertical velocity as a threshold parameter for pre-impact fall detection has been verified, effects of sensor attachment locations and methods calculating vertical acceleration and velocity on the detection performance have not been studied yet. Regarding the vertical velocity-based pre-impact fall detection, this paper investigates detection accuracies of eight different cases depending on sensor locations (waist vs. sternum), vertical accelerations (accurate acceleration based on both accelerometer and gyroscope vs. approximated acceleration based on only accelerometer), and vertical velocities (velocity with attenuation vs. velocity difference). Test results show that the selection of waist-attached sensor, accurate acceleration, and velocity with attenuation based on accelerometer and gyroscope signals is the best in overall in terms of sensitivity and specificity of the detection as well as lead time.

Quasi-Distributed Temperature Sensor Based on a V-Grooved Single-Mode Optical Fiber Covered with Ethylene Vinyl Acetate

  • Kim, Kwang Taek;Jeong, Seong-Gab
    • 센서학회지
    • /
    • 제23권4호
    • /
    • pp.229-233
    • /
    • 2014
  • In this study, a V-grooved single-mode fiber along with optical time domain reflectometry (OTDR) as a quasi-distributed temperature sensor was investigated. The external medium used to fill the V-groove affects the optical mode. The V-groove was filled with ethylene vinyl acetate (EVA) because its transmittance was sensitive to temperature. The experimental results showed that the optical loss of the sensor varies with temperature, and the sensitivity depends on the depth of the V-groove.

Analysis of Spin Valve Tunneling Magnetoresistance Sensor for Eddy Current Nondestructive Testing

  • Kim, Dong-Young;Yoon, Seok-Soo;Lee, Sang-Hun
    • 비파괴검사학회지
    • /
    • 제28권6호
    • /
    • pp.524-530
    • /
    • 2008
  • The spin valve tunneling magnetoresistance (SV-TMR) sensor performance is analyzed using Stoner-Wohlfarth model for the detection of eddy current signals in nondestructive testing applications. The SV-TMR response in terms of the applied AC magnetic field dominantly generates the second harmonic amplitude in hard axis direction. The second harmonic eddy current signal detection using SV-TMR sensor shows higher performance than that of the coil sensor at lower frequencies. The SV-TMR sensor with high sensitivity gives a good solution to improve the low frequency performance in comparison with the inductive coil sensors. Therefore, the low frequency eddy current techniques based on SV-TMR sensors are specially useful in the detection of hidden defects, and it can be applied to detect the deeply embedded flaws or discontinuities in the conductive materials.

열전대를 이용한 미세 열유속 센서의 제작 및 평가 (Fabrication and evaluation of a micro heat flux sensor using thermopile)

  • 김정훈;김범석;조형희;김용준
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2005년도 춘계학술대회 논문집
    • /
    • pp.1210-1213
    • /
    • 2005
  • Micro heat flux sensor is used in various industries to measure heat flux. In this study, a micro heat flux sensor is fabricated using the MEMS (Micro Electro Mechanical Systems) techniques. The fabricated sensor is composed in thermopile for sensor and SU-8 for thermal resistance layer. The new method of fabrication SU-8 is proposed in this study. The sensitivity is $44\;\mu{V/(W/cm^2)}$ at steady state and Reynolds number is 91322.

  • PDF