• 전기학회논문지
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• 제61권12호
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• pp.1926-1931
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• 2012

We investigated a novel fast non-uniform illumination correction method for bi-level images. The proposed method divides a bi-level image into sub-images and roughly estimates block-wise illumination by low pass filtered maximum values of sub-images. After that, we apply bilinear interpolation using the block-wise illumination to estimate non-uniform illumination, and compensate for the effect of non-uniform illumination using the estimated illumination. Since the proposed method is not based on computation intensive iterative optimization, the proposed method can be used effectively for applications that require fast correction of non-uniform illumination. In simulations, the proposed method showed more than 20 times faster speed than existing entropy minimization method. Moreover, in simulations and experiments, the restored images by the proposed method were more close to true images than images restored by conventional method.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1998년도 하계 학술대회 논문집
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• pp.122-128
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• 1998

• Journal of Biosystems Engineering
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• 제23권6호
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• pp.591-598
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• 1998

Light intensity and spectral characteristics of different types of fluorescent lamps were tested to investigate their possibility as the artificial lighting sources for the close illumination applied in the transplant production factory. Photosynthetic photon flux densitiy(PPF), illuminance and irradiance for all lamps decreased logarithmically with an increase of the vertical distance from the lighting source. The fluorescent lamp specially designed plant growth (PG lamp) showed a maximum spectral irradiance at the wavelength of 660nm. However, it showed lower irradiance than that of a standard fluorescent lamp at the range of wavelength between 500 and 600nm. On the other hand, PG lamp showed higher PPF and lower illuminance than those of the standard fluorescent lamp. The maximum peak of spectral characteristics for both of the single and twin three-bind fluorescent lamps was shorn at the wavelength of 545m and the next peaks were shown at the wavelength of 610nm and 435nm, respectively. Since the red fluorescent lamp has a narrower peak at the wavelength of 660nm, it may be useful for the supplementary red lighting. For three of standard, single three-band and twin three-band fluorescent lamps, the values of conversion factor for converting illuminance to PPF fell within the narrow range from 76 to 791x/$\mu$molㆍm$^{-2}$ ㆍs$^{-l}$ . However, for PG lamp, it was 29.71x/$\mu$molㆍm$^{-2}$ ㆍs$^{-1}$. Also, the values of conversion factor for converting PPF to irradiance of fluorescent lamp used in this study ranged between 4.85 and 5.34$\mu$molㆍm$^{-2}$ ㆍs$^{-1}$/Wㆍm$^{-2}$ .

• 한국의류학회지
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• 제44권1호
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• pp.68-83
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• 2020

This study suggests a method to predict the color appearance of textiles that shifts depending on illumination variations. The suggested method allows the calculations of lightness, chroma, and hue appearance values from the spectral reflectance values of the textile and illuminant. The accuracy of the method was evaluated through numerical and statistical comparisons between the predicted and the measured color appearance values of 24 fabric samples under CIE standard illuminant D65. As a result, there were excellent agreements between the two data sets with the error values close to zero. The predicted color appearance values of 24 samples under two illuminating (color temperature-luminance) conditions, 2700 K-100 cd/㎡ and 6500 K-100 cd/㎡, were then compared to prove the significant effect of illumination on the color appearance of textiles. The color appearance values were also compared with spectrophotometrically measured physical color attributes, that is, true colors of the samples. The physical color attributes of samples were unchanged; however, differences in color appearance under different conditions were generally much larger than the suprathreshold color difference tolerances discussed in the color science literature. Finally, the magnitude of the illumination effect depending on the physical color attributes of samples was also analyzed.

• 한국자동차공학회논문집
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• 제3권6호
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• pp.30-40
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• 1995

Optically accessible D. I. diesel engine with a rectangular combustion chamber was constructed to visualize the behaviors of sprays and flames in the combustion camber with the close conditions of pressure and temperature in an actual engine. The behaviors of sprays and flames in the combustion chamber as the operating conditions of this engine were photographed with high speed camera by Diffused Background Illumination Method. With photographs taken by this method, behavior of spray droplets injected into the combustion chamber, ignition points, and flame propagation were observed and analyzed at a time-and space-dependent fashion.

• 순환기질환의공학회:학술대회논문집
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• 순환기질환의공학회 2005년도 제5회 학술대회 초록집
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• pp.11-12
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• 2005

• 한국정보통신학회논문지
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• 제8권3호
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• pp.727-732
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• 2004

본 논문에서는 능동적 적외선 조명을 이용한 3차원 얼굴 방향 식별을 위한 새로운 방법을 제안하고자 한다. 적외선 조명 하에서 밝게 나타나는 동공을 효과적으로 실시간 검출하여 추적할 수 있는 알고리즘을 제안한다. 다른 방향의 얼굴들에서 동공의 기하학적 왜곡을 탐지하여, 3차원 얼굴 방향과 동공의 기하학적 특성 사이의 관계를 나타낸 학습 데이터를 사용하여 고유한 눈 특징 공간을 구축하였고, 입력된 질의 영상에 대한 3차원 얼굴 방향을 고유한 눈 특징 공간을 사용하여 실시간으로 얼굴 방향을 측정할 수 있었다. 실험결과 카메라에 근접한 실험 대상자들에 대하여 최소 94.67％, 최고 100％의 식별 결과를 나타내었다.

• 품질경영학회지
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• 제29권3호
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• pp.66-78
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• 2001

This paper deals with problem of determining process target value under automated visual inspection(AVI) system. Three independent error sources - digitizing error, illumination error, and positional error - which have a close relationship with the performance of the AVI system, are considered. Assuming that digitizing error is uniformly or normally distributed and illumination and positional errors are normally distributed, respectively, the distribution function for the error of measured lengths is derived when the length of a product is measured by the AVI system. Then, Optimal target values under two error models of AVI system are obtained by minimizing the total expected cost function which consists of give away, rework and penalty cost. To validate two process setting models, AVI system for drinks filling process is made up and test results are discussed.

• Journal of Plant Biology
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• 제33권3호
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• pp.197-202
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• 1990

Exogenously applied spermine, spermidine and putrescine caused a delay of senescence in fronds Lemna gibba G3 under continuous illumination. When the proximal half of a frond containing the meristematic“pockets”was removed, endogenous spermidine level in the distal half (half frond) increased initially to a miximal level, which was followed by a decline during a period of 10 days of incubation in light. No appreciable changes were observed with putrescine or spermine levels. Treatment of fronds with $\alpha$-difluromethylarginine (DFMA) resulted in both reduced level of spermidine and enhancement of chlorophyll loss in half fronds. $\alpha$-difluoromethylornithine (DFMO) was found to be virtually ineffective in either parameter. Results of experiments with ABA and kinetin indicate that there is a close correlation between the progress of senescence and spermidine level in Lemna fronds under illumination. It is suggested that endogenous level of spermidine is associated, at least in part, with frond senescence in this aquatic plant.

• 한국보건간호학회지
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• 제14권1호
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• pp.26-40
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• 2000

This study was conducted to find out residential environment, mood states, ADL(Activity Daily Living) and nursing need of the elderly who live alone. The questionnaire survey was conducted on 154 single household elderly over 65years who live n D-city, Kangwon Province. The data were collected between September 1. 1999 and October 17, 1999 and analyzed by means of SPSS package. The results were as follows; 1. The percentage of the subjects who owned their house was no were than $13\%$., which showed that they still belonged to the economically vulnerable class. As for their residential environment, the average indoor temperature and humidity level were $16.45^{\circ}C\;and\;44.62\%$ respectively during the daytime between September and October, which proved to range within the standard scope. The average indoor illumination level was, however, 43.61 Lux, which showed that their illumination environment was very poor. 2. The average score of their mood states was 3.31. which turned out to be rather low. 3. The mean score of ADL was 1.69, which showed that they didn't have any serious inconveniences in their ordinary lives. 4. The mean score of their nursing need was 275, which proved to be close to the normal level. 5. The higher the room humidity was, the higher their nursing need increased. The higher the degree of illumination level was, the lower the degree of their nursing need was and the higher the level of ADL was. 6. The major factors influencing their moon status were the frequency of their contact with children and room humidity. These two factors could account for $22\%$ of the total mood status. These results suggest that the residential environment should be necessarily considered in the psychological nursing intervention for the elderly who live alone and they should be urgently supported in terms of health policy so that they can maintain the optimum level of illumination during the daytime.