• Food Science and Biotechnology
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• 제16권3호
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• pp.337-342
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• 2007

Conventional methods for pathogen detection and identification are labor-intensive and take days to complete. Biosensors have shown great potential for the rapid detection of foodborne pathogens. Fiber-optic biosensors have been used to rapidly detect pathogens because they can be very sensitive and are simple to operate. However, many fiber-optic biosensors rely on manual sensor handling and the sandwich assay, which require more effort and are less sensitive. To increase the simplicity of operation and detection sensitivity, a binding inhibition assay method for detecting Listeria monocytogenes in food samples was developed using an automated, fiber-optic-based immunosensor: RAPTOR (Research International, Monroe, WA, USA). For the assay, fiber-optic biosensors were developed by the immobilization of Listeria antibodies on polystyrene fiber waveguides through a biotin-avidin reaction. Developed fiber-optic biosensors were incorporated into the RAPTOR to evaluate the detection of L. monocytogenes in frankfurter samples. The binding inhibition method combined with RAPTOR was sensitive enough to detect L. monocytogenes ($5.4{\times}10^7\;CFU/mL$) in a frankfurter sample.

• 한국광학회지
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• 제19권1호
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• pp.15-19
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• 2008

크기가 작고 감도가 높은 중공 광섬유를 이용한 In-Line 마이켈슨 간섭계형 전압 센서를 개발하였다. 개발된 In-Line 마이켈슨 갑섭계는 끝 단면은 단일모드광섬유에 연결되어 있고 다른 끝 단면은 깨끗하게 절단된 지름이 4 um의 공기구멍을 가지고 있으며 길이가 10 mm인 중공 광섬유로 구성되어 있다. 개발된 In-Line 마이켈슨 간섭계를 PZT위에 glue를 사용하여 고정시켜 In-Line 마이켈슨 간섭계형 전압 센서를 제작하였다. 제작된 센서는 60 Hz의 AC 전압을 인가하였을 때 출력파형의 주파수는 인가전압의 크기에 비례하였다. 그리고 출력파형의 위상은 인가전압의 크기와 거의 선형적인 관계에 있었으며 센서의 감도는 $0.065{\pi}$ radian/V였다.

• 비파괴검사학회지
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• 제31권4호
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• pp.374-381
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• 2011

최근 구조 건전성 모니터링을 위해 다양한 센서와 분석 기술들을 적용하여 기계/토목 구조물의 처짐을 측정하는 연구들이 활발히 수행되고 있다. 처짐을 측정하기 위해 사용되는 다양한 전기 기반 상용 센서의 경우, 많은 수의 센서가 설치될 때 함께 설치된 다량의 전선들은 전기적 잡음 문제를 야기하여 사용상의 어려움을 발생시킨다. 따라서 본 논문에서는 기본 센서의 문제점을 해결하면서 미세 변위를 손쉽게 측정할 수 있는 저가형의 광강도형 광섬유 변위 센서를 제안한다. 이를 위해, 광섬유 굽힘 손실 현상을 이용하여 센서부의 형태를 고안하였으며 민감도, 선형성 그리고 작동 범위를 구하기 위한 기초 실험을 수행하였다. 또한 변위 측정이 용이하고 구조물에 손쉽게 설치할 수 있도록 센서 헤드의 기구부를 새롭게 설계 제작하였으며, 이를 사용하기 위한 실시간 프로그램 또한 함께 개발하여 광섬유 변위 센서 시스템을 개발 완료하였다.

• 센서학회지
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• 제18권6호
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• pp.467-474
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• 2009

In this study, we describe the feasibility of developing a fiber-optic temperature sensor using a thermochromic material such as 2,4,5-triphenylimidazole or also called Lophine. A sensor-tip is fabricated by mixing of a Lophine powder, which has a non-toxic and hydrophobic characteristics, and an epoxy resin. The temperature change in the sensor-tip gives rise to a change in the optical absorbance of the Lophine, and the transmittance of a light through the Lophine is also changed. We have measured the intensities of modulated lights due to the change of optical absorbance of the Lophine by using of a photo-multiplier tube(PMT). The relationships between the temperatures and the output voltages of PMT are determined to measure the temperature of water. The measurable temperature range of the fiber-optic sensor is from 5 to $30^{\circ}C$.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 추계학술대회
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• pp.617-619
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• 2022

3D 프린팅 기술을 이용하여 광섬유가 내장된 임베디드 센서 구조물을 제조하였으며, 광주파수 반사 산란광 측정법 기반의 분포 센서 기술을 이용하여 대상 구조물에 인가된 스트레인 분포를 측정하였다. 측정된 분포 데이터는 대상 구조물 형상에 실시간 대입하여 3차원 시각화 표현하였다.

• 소음진동
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• 제9권3호
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• pp.565-569
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• 1999

Recently, fiber optic hydrophone is a subject which has attracted as a underwater acoustic sensor. In this study, Finite element modeling of fiber optic hydrophone for hollow cylindrical mandrel was performed and the acoustic sensitivity was calculated to estimate the performance of single element fiber optic hydrophone. And acoustic sensitivity was measured in acoustic water tank to verify the result of simulation. The result of FE analysis and experiment is -126 dB re rad/$\mu$ Pa and -128 dB re rad/$\mu$ Pa respectively.

• 센서학회지
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• 제15권3호
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• pp.186-191
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• 2006

In general, Cerenkov light is produced by a charged particle that passes through a medium with a velocity greater than that of visible light. Although the wavelength of Cerenkov light is very broad, the peak is in the almost visible range from 400 to 480 nm. Therefore, it always causes a problem to detect a real light signal that is generated in the scintillator on the fiber-optic sensor tip for dose measurements of high-energy electron beam. The objectives of this study are to measure, characterize and remove Cerenkov light generated in a fiber-optic radiation sensor tip to detect a real light signal from the scintillator. In this study, the intensity of Cerenkov light is measured and characterized as a function of incident angle of electron beam from a LINAC, and as a function of the energy of electron beam. As a measuring device, a photodiode-amplifier system is used, and a subtraction method using a background optical fiber is investigated to remove Cerenkov light.

• 센서학회지
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• 제23권4호
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• pp.245-250
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• 2014

When the charged particle travels in transparent medium with a velocity greater than that of light in the same medium, the electromagnetic field close to the particle polarizes the medium along its path, and then the electrons in the atoms follow the waveform of the pulse which is called as Cerenkov light or radiation. This type of radiation can be easily observed in a spent fuel storage pit. In optical fibers, the Cerenkov light also can be generated due to their dielectric components. Accordingly, the radiation-induced light signals can be obtained using optical fibers without any scintillating material. In this study, to measure the intensities of Cerenkov radiation induced by gamma-rays, we have fabricated the fiber-optic Cerenkov radiation sensor system using silica optical fibers, plastic optical fibers, multi-anode photomultiplier tubes, simulated spent fuel assembly and a scanning system. To characterize the Cerenkov radiation generated in optical fibers, the intensities of Cerenkov radiation generated in the silica and plastic optical fibers were measured. Also, we measured the longitudinal distribution of gamma rays emitted from the Ir-192 isotope by using the fiber-optic Cerenkov radiation sensor system and simulated spent fuel assembly.

• 센서학회지
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• 제14권4호
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• pp.244-249
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• 2005

In this study, radiation sensor tips are fabricated for remote sensing of X or gamma ray with inorganic scintillators and plastic optical fiber. The visible range of light from the inorganic scintillator that is generated by radiation source is guided by the plastic optical fiber and is measured by optical detector and power-meter. Two kinds of sensor tips are designed and fabricated such as film type and powder type. Many kinds of inorganic scintillators are used to fabricate both sensor tips, and the different wavelength of emitting lights from them are measured to determine the optimal inorganic scintillator which has maximum light output. As a radiation source X-ray generator and Ir-192 are selected to test a performance of sensor tip. It is expected that the fiber-optic radiation sensor is widely used in nuclear industry and medical applications due to its special characteristics such as good flexibility, easy in processing, long lengths and no interference to electro magnetic field.

• 전기전자학회논문지
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• 제20권4호
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• pp.367-372
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• 2016

외부 지역에서 침투하는 외부침입자에 대한 침입탐지를 위한 기초적인 연구 수행을 위하여 광섬유 ROTDR (Rayleigh Optical Time Domain Reflectometer) 센서를 설계 및 기초 연구를 수행하였다. 외부침입자를 탐지하기 위한 센서는 침입 탐지판을 제작하여 모래 속에 매설하여 실내에서 모형을 설치하여 침입탐지 실험을 수행하였다. ROTDR센서의 신호 분석은 검출정도에 따른 신호의 특성을 분석하였다. 광섬유 ROTDR 센서는 크게 20kg, 40kg, 60kg, 그리고 80kg 등의 무게별로 4등급으로 구분하여 넓은 영역에 걸쳐 외부 침입자를 감시하기 위한 장거리용을 사용하였다. 결과 본 논문에서의 광섬유 센서는 사회중요 기반시설의 외부침입자 감시용 실시간 모니터링의 응용에 가능함을 확인 하였다.