• Journal of Sensor Science and Technology
• /
• v.10 no.5
• /
• pp.279-285
• /
• 2001

The capnograph system for determining the partial pressure of carbon dioxide in the blood of a patient was developed based on the NDIR(non-dispersive infrared) absorption technology. NDIR gas analyzing method requires an optical absorption chamber and signal processing hardware. In this paper, we have designed and implemented NDIR type $CO_2$ gas chamber in consideration of the time response characteristics and lamp chopping frequency. And we have implemented signal processing hardware using two infrared sources to reduce the thermal background effect. The implemented gas chamber and signal processing hardware were tested in the temperature variation experiment and human expiratory experiment. The results showed that the system could produce a stable output signal and a good $CO_2$ gas concentration curve like a typical capnogram.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.10 no.3
• /
• pp.349-356
• /
• 2015

Remote monitoring partial discharge sensor, equipping with hybrid filter combining optical and electrical noise reduction capabilities and with signal integrating function to calculate total arc energy, was investigated. Hybrid filter showed insensitivity to fluorescent and incandescent lamps under simulated distribution panel condition. Signal integrating function showed selective detection capability corresponding to different arc energy levels, while convention arc sensor had difficulty to discriminate arc energy level due to bursty arc waveform and peak level detection characteristics. The sensor showed possibility for application to remote monitoring partial discharge sensor, since it detected arc energy level corresponding to normal open and close discharge in low voltage 100A MCCB at 2m distance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1997.04a
• /
• pp.513-517
• /
• 1997

수중음향 센서로서 감도가 높고 제작이 비교적 용이한 광섬유 하이드로폰은 근래에 미국 및 유럽 등지에서 활발히 연구 개발되고 있다. 본 논문에서는 알루미늄 맨드릴에 150 m 길이의 광섬유를 감아 광섬유 하이드로폰을 제작하였다. 광섬유 하이드로폰의 음향 감지 성능을 보기 위하여 Mach-Zehnder형 광간섭계를 구성하고 신호 안정화를 위하여 3 * 3 광결합기를 이용하였으며 이것을 음향수조에서 실험을 하였다. 음향신호의 주파수를 2kHz로 구동하였을 때 제작된 광섬유 하이드로폰은 음향신호를 안정적으로 감지함을 확인하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.05c
• /
• pp.242-246
• /
• 2002

인체의 손가락 끝에서 발생하는 맥의 파형과 온도, 피부저항을 측정할 수 있는 복합센서를 설계 제작하였다. 인체신호를 계측하는 여러 가지 방법 중에서 손가락 끝의 맥 파형을 계측하고자 광센서를 활용하여 계측시스템을 구현하였고 특성을 평가하였다. 그 결과 체온측정은 대략 $0.01^{\circ}C$의 분해능을 구현 할 수 있었고, 피부저항 측정은 최대 $5M{\Omega}$까지 측정 가능하고 최소분동은 $5k{\Omega}$ 정도이며, 맥박측정은 새롭게 포토센서를 적용하여 미소진동을 측정할 수 있었다.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.866-867
• /
• 2015

화재 및 인명사고의 약 40%이상이 아크플래시사고로 인한 원인으로 밝혀지고 있다. 이에 아크 플래시 발생으로 인한 2차 사고 방지가 산업 경제적 측면에서 중요하다고 판단하여 본 연구에서는 초고속자외선 검출 시스템을 구현하였다. 아크 플래시 신호를 광파이버 포인트 센서 및 광섬유 루프센서를 이용하여 초고속 광검출 및 고속 신호처리 컨트롤러를 이용해 차단기 트립 개시 신호 출력까지 시간을 1.5ms 이내로 출력하는 것을 목표로 하였으며 테스트베드를 통해 구축한 시스템에서 아크 발생 후 소요시간 약 1ms의 트립 개시 신호를 출력하는 초고속 아크 검출 시스템을 개발하였다.

• Korean Journal of Optics and Photonics
• /
• v.16 no.4
• /
• pp.319-325
• /
• 2005

A signal processing method for white light interferometry (WLI), which performs a series of analog signal processing steps to locate the central interference fringe position at high speed: is developed and applied to a WLI temperature sensor system. We found that the new method has random walk of $0.019^{\circ}C/\sqrt{Hz}$ with good linearity. However, the temperature change in the path-matching interferometer results in drift of the measured sensor output. The temperature dependence of drift in the WLI temperature sensor system, was calculated to be $1.42{\mu}m/^{\circ}C$. It is also found that the relationship between the peak spacing in the interferogram and the spacing measured by the method can be nonlinear when the fringe spacing is comparable to the coherence length of the source.

• Proceedings of the KSRS Conference
• /
• 2000.04a
• /
• pp.131-136
• /
• 2000

Ocean Scanning Multi-spectral Imager (OSMI)는 다목적 실용위성 (KOMPSAT) 1호기 아리라위성에 탑재되어 1999년 12월 21일 발사된 해양 관측 기기이다. OSMI는 발사후 3년 이상 생물학적 해양지리학 연구를 위해 전세계 바다색을 관측하는 임무를 수행할 것이다. OSMI는 센서 성능의 궤도상 보정을 위해 태양광 보정과 암흑 보정을 수행한당. 태양광 보정은 궤도상에서 장기간에 걸친 해양 결상계의 노화에 따른 성능 변화 감지 및 보정에 있다. 발사 직후의 초기 태양과 보정 측정 자료는 추후 성능 변화 감지에 대한 기준이 될 뿐만아니라 발사 직후 OSMI 센서 성능 파악 및 점검에도 사용될 수 있으므로 매우 중요하다. 태양광 보정의 구조 및 광학적 특성을 분석하고 OSMI 주요 관측파 장대역별로 태양광 보정계의 출력신호량을 예측하였다. 초기 운영 기간동안 얻은 OSMI 태양광 보정계의 발사후 최초 측정 자료를 분석하고 발사전 예측 성능과 비교하였다. 이 연구는 OSMI 센서 보정 및 영상 품질 이해에 유용할 것이다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.21 no.1
• /
• pp.1-9
• /
• 2007

This study proposes to increase the energy-saving effects by reducing excessive intensity of radiation of artificial lighting through analyzing daylight incident. A photosensor sends amounts of detected luminous flux to digital control unit(DCU) as a signal and then, it can decide dimming ratios, received a proper dimming signal from DCU. Generally it is effective to control artificial lighting with the different control ratio of each zone by setting a photosensor as same number and rows as artificial lighting. However, it is ineffective to do in initial costs of systems aspect in offices. As a result of grasping the distribution of daylight previously and analyzing daylight and dimming data, we can dim different dimming ratios to each zone of artificial lighting by a single photosensor.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.7 no.6
• /
• pp.1555-1560
• /
• 2012

Recently, it has been increasing attention on health care that can provide remote medical service to an aging population, people with disabilities and people having a medical checkup periodically due to increasing people's average life span. Home health care system should provide reasonable cost, on-line basic health status monitoring, embedded basic medical helper function and intuitive interface. In this paper, we developed a prototype of 3G networked pulse measurement system that can detect pulse signal information from subject's fingertip using the optical sensor. The prototype had been analyzed in terms of abnormalities, feeling, timing and pulse counting accuracy. Finally we evaluated its suitability.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.10
• /
• pp.1085-1091
• /
• 2014

We developed a single-channel thread sensor for a rotary bobbin by optical sensing and analyzed the signal characteristics. A specially designed mount made of ABS (acrylonitrile-butadiene-styrene) resin that encapsulated an optical sensor was fabricated by using a 3D printer and was attached to the rotary bobbin system. Stable control on a weaving machine was achieved by observing the difference in the output signals of an optical sensor system, which vary significantly according to the states of the thread in the weaving operation. The optical sensor effectively detects an unintentional thread cut and run-out during weaving fast enough to enable prompt stopping of the weaving machine, thereby minimizing the loss of expensive fabrics.