• 한국콘텐츠학회논문지
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• 제11권5호
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• pp.205-215
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• 2011

분광특성의 차이로 필름은 자외선에 민감한데 반해 디지털 카메라의 센서는 적외선에 굉장히 민감하다. 이에 따라 CCD 또는 CMOS를 사용하는 모든 디지털 카메라에는 IR Cut-Off Filter가 센서전면에 장착되어 있다. 이상적으로 100% 적외선을 차단하여야 하지만 실험 결과 완전히 적외선을 차단하지 못하고 있었으며, 각 카메라마다 적외선 투과량 또한 달랐다. 따라서 본 연구는 디지털 카메라에 장착되어 있는 IR Cut-Off Filter의 기계적 특성에 의해 투과되는 미량의 적외선이 디지털 화상이미지에 끼치는 영향을 분석하는 데 그 목적이 있다. UV필터를 장착한 상태(적외선 투과상태)와 UV-IR필터를 장착한 상태(적외선미투과상태)를 비교분석한 결과, 잡음(Noise)과 색 재현력 평가에서는 그 차이가 미세하거나 거의 동등한 수준이지만, 동적 폭(Dynamic Range)과 해상도에는 IR Cut-Off Filter를 통해 투과되는 미량의 적외선이 어느 정도 영향이 있음을 확인할 수 있었다.

• 대한화장품학회지
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• 제47권4호
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• pp.289-296
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• 2021

본 연구에서는 국내 유통 중인 민감성 피부 대상 자외선 차단제의 안전성 조사를 위해 무기 자외선 차단제 27 건 및 어린이용 자외선 차단제 23 건을 수거하여 자외선 차단 성분 17 종, 보존제 13 종 및 중금속 5 종의 사용 및 혼입 실태을 조사하였다. 그 결과 자외선 차단 성분은 티타늄디옥사이드(41 건), 징크옥사이드(29 건), 비스-에칠헥실옥시페놀메톡시페닐트리아진(10 건) 에칠헥실살리실레이트(8 건) 및 에칠헥실메톡시신나메이트(8 건)순으로 검출되었으며, 보존제는 페녹시에탄올(6 건), 안식향산(1 건), 디히드로초산(1 건) 순으로 검출되었다. 확인된 자외선 차단성분은 모두 표시 사항에 적합 하였으나, 1 개 제품에서 표시사항 외 보존제 성분인 페녹시에탄올이 0.1% 농도로 검출되었다. 중금속 납, 카드뮴, 비소, 안티몬, 니켈은 불검출에서 3.6 ㎍/g로 다양한 농도로 검출되었다. 이번 연구에서 확인된 자외선 차단성분, 보존제 및 중금속은 화장품 안전기준 등에 관한 규정의 성분별 최대 배합한도 및 최대 허용량 기준에 적합하였다.

• 한국농공학회논문집
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• 제51권5호
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• pp.95-100
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• 2009

The water purification systems have been hardly used for agricultural purpose due to their complicated compositions and high costs for farmers, while only simple filtrations have been applied to irrigation systems in order to prevent the system from clogging problems. This study therefore developed a clean water supplying system, the Filter-Disinfection-Adsorption (FDA) system, especially for greenhouse cultivation of where low quality of water is available. This system has also been produced for providing convenience water to farmers in the areas of no water supply service systems for the purpose of washing their bodies or agricultural machineries after farm work. The FDA system consists of three stages of purification processes with an integral module, including disk and teflon filtrations and Ultraviolet (UV) sterilization processes. Indoor experiments were undertaken with a trial product of the FDA system to test its performance. The operation test of the process was performed as well as the condition check of each item including UV module, filters, control panel, pump, valves, etc. The results shows good performance of each test with no critical problems. The initial and maintenance costs were also analysed with other purification systems. From the comparisons, the FDA system found to be very economical and easy to use.

• 제어로봇시스템학회논문지
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• 제14권8호
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• pp.767-773
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• 2008

This paper presents a localization system based on the use of electric compass and tracking IR light source. Digital RGB(Red, Green, Blue)signal of digital CMOS Camera is sent to CPLD which converts the color image to binary image at 30 frames per second. CMOS camera has IR filter and UV filter in front of CMOS cell. The filters cut off above 720nm light source. Binary output data of CPLD is sent to DSP that rapidly tracks the IR light source by moving Camera tilt DC motor. At a robot toward north, electric compass signals and IR light source angles which are used for calculating the data of the location system. Because geomagnetic field is linear in local position, this location system is possible. Finally, it is shown that position error is within ${\pm}1.3cm$ in this system.

• 한국염색가공학회지
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• 제30권3호
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• pp.159-167
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• 2018

Here we designed and synthesized new zinc phthalocyanines and structures were fully confirmed by spectral and elemental analysis. All phthalocyanines have a very good solubility in industrial solvents like chloroform, dichloromethane, dimethyl sulfoxide, N,N-dimethyl formamide, propylene glycol monomethyl ether acetate (PGMEA), acetone, tetrahydrofuran and acetonitrile. UV-Visible absorption and transmittance in PGMEA showed that these dyes have suitable spectral properties for LCD color filters. By Triton X surfactant study, we confirmed that these dyes are not showing any aggregation in PGMEA. We dissolved the all phthalocyanines in LCD fabricating solvent (PGMEA), and all phthalocyanines showed more than 8 wt% of solubility. Finally, all of these results concluded that PCK1, PCK2 and PCK3 are fit for LCD green color filter.

• 분석과학
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• 제8권4호
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• pp.1101-1108
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• 1995

Acousto-optic tunable filter is a compact, all solid state electronic dispersive device. It is based on the acousto-optic interaction in an anisotropic crystal. Compared to conventional grating monochromators. the AOTF has no moving parts, wider spectral tuning range (from UV through visible and near-IR to IR), higher throughput, higher resolution, faster scanning (${\mu}s$) and random wavelength access. These features make it possible to use the filter to develop novel instruments which are not possible otherwise. The instrument development and unique advantages of such AOTF based instruments including the multidimensional fluorimeter, the multiwavelength thermal lens spectrometer, and the detectors for HPLC and flow injection analysis are described.

• 한국염색가공학회지
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• 제33권4호
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• pp.169-181
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• 2021

Five dyes based on phthalocyanine, a dye on azo, and a dye on anhraquinone were prepared from corresponding starting material to investigate the effects of substituent on thermal-stability of dyes which is essentially required to apply to the color filters. Synthesized dyes were confirmed their chemical structure using by 1H-NMR, MASS and Elemental analysis. The thermal-stability was evaluated by the weight reductions measured by TGA analysis comparing to that of conventional C.I. Pigment Blue 15:6. The absorption maxima were measured by UV-VIS spectrophotometer then the effects of substituent on absorption maximum was also investigated.

• 상하수도학회지
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• 제22권4호
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• pp.467-473
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• 2008

Natural organic matter (NOM) removal by physico-chemical adsorption and biological oxidation was investigated in five slow sand filters with different media depths. Non-purgeable dissolved organic carbon(NPDOC) and $UV_{254}$ absorbance were measured to evaluate the characteristics of NOM removal at different filter depths. Removal efficiency of NOM was in the range of 10-40% throughout the operation time. At start-up of the filters packed with clean sand media, NOM was probably removed by physico-chemical adsorption on the surface of sand through the overall layer of filter bed. However, when Schumutzdecke layer was built up after 30 days operation, the major portion of NPDOC was removed by biological oxidation and/or bio-sorption in lower depth above 50 mm. NOM removal rate in the upper 50 mm filter bed was $0.82hr^{-1}$. It was about 20 times of the rate($0.04hr^{-1}$) in the deeper filter bed. Small portion of NPDOC could be removed in the deeper filter bed by both bio-sorption and biodegradation. SEM analysis and VSS measurement clearly showed the growth of biofilm in the deeper filter bed below 500 mm, which possibly played an important role in the NOM removal by biological activity besides the physco-chemical adsorption mechanism

• Journal of Biosystems Engineering
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• 제35권6호
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• pp.420-425
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• 2010

We produced a basic system of sterilization of nutrient solution based on the characteristics of coated filter with the visible light-reactive titanium oxide photocatalyst according to the findings of the first stage. We developed a model system with a proper number and arrangement of filter elements, the visible light-reactive titanium oxide photocatalyst according to findings from the basic performance test. Main results of this study were as followers; The ceramic filters showed the best performance of sterilization of nutrient solution. The visible light-reactive titanium oxide photocatalyst sterilized more effectively the nutrient solution under the sunlight than UV light. The sterilization performance by passing repeatedly through a few filter was more efficient than that by treating simultaneously with a large number of filters. The filter with 15ppi in pore size, 20 mm in thickness, and 3 layers in titanium oxide coating was desirable in the intensity and sterilization performance.

• Journal of Advanced Marine Engineering and Technology
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• 제38권1호
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• pp.48-55
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• 2014

UV 발생용 플래시램프의 전원공급장치는 강력한 아크방전을 유발하기 위하여 높은 승압 비를 갖는 전압변환회로를 가지고 있다. 일반적인 구조는 높은 승압비의 트랜스포머와 배전압정류방식(코크라프트 올튼 회로 등)으로 방전관의 절연을 파괴함과 동시에 방전관에 전류를 급격히 통과시키는 방식으로 구동한다. 이 때, 제논방전관의 방전특성상 입력전류를 제한하지 않으면 방전관의 과다 발열, 전극손실, 봉입기체의 산화가속 등으로 수명저하의 원인이 되므로, 반드시 방전관에 유입되는 전류를 제한해야 되며, 이를 Ballast라 하는데 일반적으로 인덕터나 저항을 사용하여 인입전류량을 제한한다. 트랜스포머의 자가 공진(self-resonance)을 이용하면 낮은 1, 2차권선 비에도 고유주파수의 전후에서 비교적 높은 피크 전압을 얻을 수 있다. 또한 트랜스포머의 특정주파수에서 고유임피던스 성분을 이용하여 출력전압을 필터링하면 제논방전관이 자가 발진방식으로 동작하므로 종래의 회로구성보다 간단하고 경제적인 아크방전 파워 스테이지의 구성이 가능하다.