• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.241-242
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• 2012

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2007년도 High Temperature Superconductivity Vol.XVII
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• pp.36-36
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• 2007

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 동계학술발표회 논문집
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• pp.87-88
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• 2008

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 추계학술발표회
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• pp.875-876
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• 2005

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.140.1-140.1
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• 2015

Currently, As Plasma application is expanded to the industrial and medical industrial, Low temperature plasma characteristics became important. Especially in Medical industrial, Low temperature plasma directly adapted to human skin, so their plasma parameter is important. One of the plasma parameters is electron density, some kinds of method to measuring electron density are Thomson scattering spectroscopy and Millimeter-wave transmission measurement. But most methods is expensive to composed of experiment system. Heterodyne interferometer system is cheap and simple to setting up, So we tried to measuring electron density by Laser heterodyne interferometer. To measuring electron density at atmospheric pressure, we need to obtain the phase shift signal. And we use a heterodyne interferometer. Our guiding laser is Helium-Neon laser which generated 632 nm laser. We set up to chopper which can make a laser signal like a pulse. Chopper can make a 4 kHz chopping. We used Needle jet as Ne plasma sources. Interference pattern is changed by refractive index of electron density. As this refractive index change, phase shift was occurred. Electron density is changed from Townsend discharge's electron bombardment, so we observed phenomena and calculated phase shift. Finally, we measured electron density by refractive index and electron density relationship. The calculated electron density value is approximately 1015~1016 cm-3. And we studied electron density value with voltage.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1140-1145
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• 2004

Laser-induced incandescence (LII) is introduced as a valuable tool for the characterization of nanoparticles in flame environments. This technique is based on the heating of the particles by a short laser pulse and the subsequent detection of the thermal radiation. It has been applied successfully for the investigation of soot in different fields of application. The evaluation of the temporal decay of the laser-induced incandescence (LII) signal from soot particles is introduced as a technique to obtain two-dimensional distributions of particle sizes and is applied to a laminar diffusion flame. This novel approach to soot sizing exhibits several theoretical and technical advantages compared with the established combination of elastic scattering and LII, especially as it yields absolute sizes of primary particles without requiring calibration. With this technique a spatially resolved 2-D measurement of soot primary particle sizes is feasible in a combination process form the ratio of emission signals obtained at two delay times after a laser pulse, as the cooling behavior is characteristic of particle size.

• Journal of Mechanical Science and Technology
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• 제15권9호
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• pp.1311-1318
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• 2001

It is necessary to diagnose accurately the characteristics of soot formation and oxidation in a diesel engine. Whereas past measurement techniques for soot concentration give limited information for soot, laser-based two-dimensional imaging diagnostics have a potential to provide temporally and spatially superior resolved measurements of the soot distribution. The technique using laser sheet beam has been applied to an optically accessible diesel engine for the quantitative measurement of soot. The results provided the information for reduction of soot from the diesel engine. Both LIS (Laser Induced Scattering) and LII (Laser Induced Incandescence) techniques were used simultaneously in this study. The images of LIS and LII showed the quantitative distribution of the soot concentration in the diesel engine. In this study, several results were obtained by the simultaneous measurements of LIS and LII technique. The diameter and number density of soot in combustion chamber of the test engine were obtained from ATDC 20 degree to 110 degree. The soot diameter increased about 37% between ATDC 20 degree and 110 degree. The number density of soot, however, decreased significantly between ATDC 40 degree and 70 degree.

• 한국의학물리학회지:의학물리
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• 제25권2호
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• pp.116-121
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• 2014

본 본문은 Bio-MEMS 공정으로 제작한 마이크로 세포 분석 바이오칩을 사용하여 적혈구의 광학적 특성을 전압으로 측정한 실험이다. Bio-MEMS 공정을 이용하여 세포의 원활한 이동과 측정 분석에 사용되는 글라스에 채널 패턴 에칭을 위하여 포토리소그래피(photolithography)와 산화완충식각(BOE: buffered oxide etchant) 공정 조건, 세포 분석과 정보 전달에 사용되는 광섬유의 에칭을 위하여 산화완충식각 공정 조건, 세포나 유체를 칩과 외부의 전달 등에 사용되는 글라스의 홀을 위하여 전기화학방전(ECD: electro chemical discharge) 공정 조건, 글라스 접합을 위한 자외선반응접합(UVSA: ultraviolet sensitive adhesives) 공정 조건을 정립하였다. 또한 유체나 세포의 흐름 제어를 위한 라미나 흐름 조건, 적혈구세포에 대한 산란빔 파형을 측정하였다. 적혈구 실험을 통하여 출력 광섬유의 각도에 따른 산란빔이 출력측의 광섬유각도가 $0^{\circ}$일 때 약 17 V, 각도가 $5^{\circ}$일 때 약 10 V, 각도가 $10^{\circ}$일 때 약 6 V, 각도가 $15^{\circ}$일 때 약 4 V의 전압(Vpp)으로 측정되었다. 따라서 마이크로 세포 분석 바이오칩 제작의 소형화, 단순화, 공정신간 단축, 정량화하였고 적혈구의 광학적 특성을 측정을 측정함으로써 의공학(biomedical), 바이오칩공학(biochip), 반도체공학(semiconductor), 생물정보학(bioinformatics) 등의 응용과학 분야 발전에 기여할 것으로 기대한다.

• 한국연소학회지
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• 제23권1호
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• pp.1-7
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• 2018

The effect of LII interference on the measurement of LIF signals from PAH in a diffusion flame has been investigated. Argon-ion laser at 488 nm was vertically or horizontally polarized, and irradiated to the centerline of the flame at varying flame height. Signals from PAH-rich regions measured at 515 nm were mostly LIF signals, however, signals from soot-rich regions were determined to be mixed with Mie scattering signals and/or LII signals. Signals measured 1 mm above the excitation height were mostly LII signals from soot particles. The results show that a quantitative determination of the LIF's contribution to the measured signals would be difficult as long as the experimental setup described here is used for the regions where PAHs and soot particles exist together.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1998년도 추계학술대회
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• pp.199-200
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• 1998

The mucociliary system is one of the most important airway defense mechanisms, and knowledge of the ciliary beat frequency(CBF) is important in the understanding of this system. Using a laser light scattering method and fiber optic probe, we developed a simple and practical instrument for real-time in vivo measurements of CBF of cells in human nasal cavity. From the ciliated epithelium cells in an anterior end of middle terminator in nasal cavity, the signals of ciliary movement are transferred into a PC and analyzed by a autoregressive(AR) power spectrum. The mean CBF of 8 normal subjects was $7.1{\pm}1.1$(Hz). This instrument provided a convenient and reliable method of studying the mucociliary activity in the respiratory tract.