• 대한전자공학회논문지
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• 제9권4호
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• pp.7-16
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• 1972

고체화된 연산증폭기를 중심으로 구성한 광전측광장치를 구성하였다. 광원에 대응하여 광전자증배관에서 얻는 미소전류의 증폭과 별의 등급측정을 위한 대수변환은 동일연산증폭기의 변형으로 얻고 있다. 측정기능의 한계는 주로 증폭기입력단의 bias전류에 좌우되므로 이것은 광산증폭기의 선택상 주요기준이 될 것이다. 이러한 연산증폭기는 종래 전위계진공관 혹은 진동용량형전위계 등으로 가능하였던 각종 미소전류·전압의 증폭에 높은 신뢰성과 경제적인 증폭방식으로 적용된다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1083-1086
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• 2005

Light scattering measurement system that can evaluate light scattering characteristic from defects on silicon wafer surface has been developed. The system uses $Ar^+$ laser as an illumination source, and a highly sensitive photomultiplier tube (PMT) for detecting scattered light from defects. Unlike with conventional measurement system, our system has ability to measure scattered light pattern from wide range of scattering angles with changeable incidence condition. It is shown that our developed system is effective to discriminate the types and sizes of defects from basic experimental results using a microscatch and a PSL sphere.

• 한국연소학회지
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• 제11권3호
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• pp.18-25
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• 2006

The present studying is aimed to establish the relationship between flame chemiluminescence$(OH^*,\;CH^*,\;C_2^*)$ intensities and combustion conditions such as $NO_x$ emission characteristics. Measurements are made for $OH^*,\;CH^*,\;C_2^*$ radicals in gas & light oil diffusion flames. At turbulent nonpremixed combustion mode, the equivalence ratio is varied. The optical emissions were measured by photomultiplier(PMT) using optical band pass filter and spectrometer system. The experimental results showed that the ratio of radicals and $NO_x$ emission characteristics have exponential correlations and equivalence ratio characteristics have linear correlations at this experimental conditions.

• Journal of Astronomy and Space Sciences
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• 제6권2호
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• pp.109-117
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• 1989

A total of 266 photoelectric observations(91 in V, 93 in B, and 82 in U) for an eclipsing binary, ZZ Cnc, has been secured by using the 61-cm reflector and an uncooled iP21 photomultiplier phototube of Yonsei University Observatory during 4 years from March 1984 to May 1988. One time of minimum light, JD 2446887.534 is obtained. Although Kim et al.(1988) suggested the possibility of the period change, the present study shows that the orbital period of ZZ Cnc should be constant. According in a reasonable interpretation of the eclipse light curves. Min I = JD Hel 2446887.574+25d.5944E $pm$2 $pm$2 may be useflul as new light elements for future observations.

• 천문학논총
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• 제5권1호
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• pp.65-84
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• 1990

The temperature effects of the KNU UBV photometric system are investigated, using the HAMAMATSU 1P21 data. The variation of the passband width of V-band with temperature is about $5{\AA}/^{\circ}C$ while those of B-band and U-band are negligible. This large effect of V-band causes a significant variation of V-mag. and (B-V)-color with temperature such as ${\sim}0.02mag/^{\circ}C$ in both cases. This result strongly suggests that in the photometric observations of binary stars, the temperature effects of the response of photomultiplier and the passband of filters must be considered to avoid the systematic variation in magnitude and color particularly at the minimum of light curve.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.512-514
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• 1989

A time-correlated single photon counting system combined with a mode locked $Ar^+$ laser has been utilized to measure the fluorescence decay. A side-on type photomultiplier tube has been used as a photon detector. By restricting the sensitive area and the position of the photocathode, the transit time differencies of photoelectrons in PMT has been reduced. The fluorescence life time of rhodamin 6G in ethylene glycol measured 3.9$\pm$10 ns.

• Journal of Radiation Protection and Research
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• 제26권3호
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• pp.161-165
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• 2001

We have developed a position-sensitive proton recoil telescope (PSPRT) which employs a position-sensitive photomultiplier (PS-PMT) and a scintillator for both a radiator and a proton-detector. This system is expected to achieve high energy resolution under a large solid angle, because it enables to obtain the information not only on the proton energy but also the recoil angle from the position data for both detectors. The response of the PSPRT for 14.1 MeV mono-energetic neutrons was measured, and the PSPRT proved to be operating as expected.

• Journal of Mechanical Science and Technology
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• 제17권7호
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• pp.1083-1094
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• 2003

This study represents an assessment of the phase-Doppler technique to the measurements of dense droplet laden jet. High-pressure injection fuel sprays have been investigated to evaluate the use of the Phase-Doppler anemometry (PDA) technique. The critical issue is the stability of the phase-Doppler anemometry technique for dense droplet laden jet such as Diesel fuel spray in order to insure the results from the drop size and velocity measurements are repeatable, consistent, and physically realistic because the validation rate of experimental data is very low due to the thick optical density. The effect of shift frequency is minor, however, the photomultiplier tube (PMT) voltage setting is very sensitive to the data acquisition and noise in dense droplet laden jet. The optimum PMT voltage and shift frequency should be chosen so that the data such as volume flux and drop diameter do not change rapidly.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.35-37
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• 2002

Conceptual design of the next generation PET with both high sensitivity and high spatial resolution has been performed. A detector unit using a depth encoding scheme was designed and constructed for trial. The unit consists of four Gd$_2$SiO$\sub$5/:Ce crystal blocks in a 2x2x4 array coupled to a position-sensitive photomultiplier tube having metal channel dynodes and 4x4 multi-anodes. Our proposed detector is a very reliable and simple solution suitable for volume PET devices since the proposed depth encoding scheme does not need additional photo-detectors.

• 한국전기전자재료학회논문지
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• 제14권3호
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• pp.246-250
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• 2001

ZnO thin films for light emission device have been deposited on sapphire and silicon substrates by pulsed laser deposition technique(PLD). A Nd:YAG laser was used with the wavelength of355 nm. In order to investigate the emission properties of ZnO thin films, Pl measurements with an Ar ion laser a light source using an excitation wavelength of 351 nm and a power of 100 mW are used. All spectra were taken at room temperature by using a grating spectrometer and a photomultiplier detector. ZnO exhibited Pl bands centers around 390, 510 and 640 nm, labeled near ultra-violet(UV), green and orange bands. Structural properties of ZnO thin films are analyzed with X-ray diffraction(XRD).