• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1614-1614
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• 2001

The sweetness (。Bix) of fruit is the main quality factor contributing to the fruit taste. The brix of the apple fruit can be measured non-destructively by near infrared (NIR) spectroscopy, allowing the sweetness grading of individual apple fruit. However, the fruit quality is influenced by various factors such as growing location, producing year, variety and harvest time etc., accordingly the robust NIR calibration is required. In this experimental results are presented the influence of two variations such as growing location and producing year of apple fruit in establishing of calibrations for sweetness, and developed a stable and highly accurate calibration. Apple fruit (Fuji) was collected every year from 1995 to 1997 in 3 different growing locations (Andong, Youngchun and Chungsong) of Kyungpook in Korea. NIR reflectance spectra of apple fruit were scanned in wavelength range of 1100∼2500nm using an InfraAlyzer 500C (Bran+Luebbe) with halogen lamp and PbS detector. The multiple linear regression and stepwise was carried out between the NIR raw spectra and the brix measured by refractometer to select the best regression equations. The calibration models by each growing district were well predicted to dependent sample set, but poorly predicted to independent sample set. Combined calibration model using data of three growing districts predicted reasonable well to a population set drawn from all growing districts(SEP = 0.69%, Bias=-0.075). The calibration models by each harvest year were not transferable across harvest year, however a combined calibration model using data of three harvest years was sufficiently robust to predict each sample sets(SEP = 0.53%, Bias = 0.004).

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.4104-4104
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• 2001

Milk somatic cell count (SCC) is a recognized indicator of cow health and milk quality. The potential of near infrared (NIR) spectroscopy in the region from 1100 to 2500nm to measure SCC content of cow milk was investigated. A total of 196 milk samples from 7 Holstein cows were collected for 28 days, consecutively, and analyzed for fat, protein, lactose and SCC. Three of the cows were healthy, and the rest had mastitis periods during the experiment. NIR transflectance milk spectra were obtained by the InfraAlyzer 500 spectrophotometer in a wavelength range from 1100 to 2500 nm. The calibration for logSCC was performed using partial least square (PLS) regression and different spectral data pretreatment. The best accuracy of determination was found for equation, obtained using smoothed absorbance data and 10 PLS factors. The standard error of calibration was 0.361, calibration coefficient of multiple correlation 0.868, standard error of prediction for independent validation set of samples 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. The accuracy of logSCC determination by NIR spectroscopy would allow health screening of cows, and differentiation between healthy and mastitic milk samples. When the spectral information was studied it has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. In the case of mastitis, when the disease occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1258-1258
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• 2001

Estimation of sugar and reducing sugar content in molasses is very important task in sugar refineries. Conventional methods of determination of sugar content in molasses samples are highly time consuming and employ hazardous chemicals. Due to the physical properties of molasses, probability of error in conventional analytical techniques is high. These methods have proven to be inefficient for a process control in any sugar industry. Hence development of a rapid, inexpensive, physical and also accurate method for sugar determination in molasses will be highly useful. Near Infrared spectroscopy is being widely used worldwide as an analytical technique in food industry. The technique offers the advantage of being non-destructive and rapid. The present paper highlights the potential of near infrared reflectance spectroscopy as a rapid and automated analytical technique for determination of sugar and reducing sugar content in molasses. A number of molasses samples were collected during and after the sugar season from Havana Sugar Industry, Havana. The samples were chosen so as to obtain a wide range of concentration of sugar and reducing sugars. This was done in order to achieve a good calibration curve with widely spread data points. These samples were scanned in the region of 1100 - 2500 nm in diffuse reflectance mode. An indigenous ELICO NIR spectrophotometer, modified according to the requirements of sugar industry was used for this purpose. Each sample was also analyzed simultaneously by standard chemical methods. Chemical values were taken as reference for near infrared analysis. In order to obtain the most accurate calibration for the set of samples, various mathematical treatments were employed. Partial Least Square method was found to be most suitable for the analysis. A comparison is made between the actual values (chemical values) and the predicted values (NIR values). The actual values agree very well with the predicted values showing the accuracy of the technique. The validity of the technique is checked by predicting the concentration of sugar in unknown molasses samples using the calibration curve. The present investigation assesses the feasibility of the technique for on-line monitoring of sugars present in molasses in sugar industries.

• 한국토양비료학회지
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• 제33권4호
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• pp.242-246
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• 2000

근적외 분광분석기를 이용하여 과수의 영양진단을 위한 신속한 엽분석 수단으로 활용하고자 본 시험을 수행하였다. 사과 '후지'품종 잎 177점, 포도 '캠벨얼리' 품종 잎130점의 시료를 이용하여 1,100~2.500nm까지 근적외영역의 흡수스펙트럼을 측정하였다. 총질소 분석은 살리실산-황산으로 분해후 켈달 증류하여 측정하였다. 근적외 스펙트럼과 총 질소함량과의 상관분석을 이용, 검량식을 개발하였고 화학분석한 결과에 대한 예측식을 구하였다. 사과는 중회귀계수 0.965, 검량식의 표준오차 0.086, 포도는 중회귀계수 0.926, 검량식의 표준오차 0.152이었다. 개발된 검량식을 이용하여 예측식을 작성한 결과는 사과의 경우 0.360, 포도 0.210의 결과를 얻었다. 지역간, 년차간 발생되는 변이가 보정된다면 신속한 엽분석 수단이 될 것으로 판단된다.

• Current Optics and Photonics
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• 제7권2호
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• pp.200-206
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• 2023

Near-infrared (NIR) sensing technology using CMOS image sensors is used in many applications, including automobiles, biological inspection, surveillance, and mobile devices. An intuitive way to improve NIR sensitivity is to thicken the light absorption layer (silicon). However, thickened silicon lacks NIR sensitivity and has other disadvantages, such as diminished optical performance (e.g. crosstalk) and difficulty in processing. In this paper, a pixel structure for NIR sensing using a stacked CMOS image sensor is introduced. There are two photodetection layers, a conventional layer and a bottom photodiode, in the stacked CMOS image sensor. The bottom photodiode is used as the NIR absorption layer. Therefore, the suggested pixel structure does not change the thickness of the conventional photodiode. To verify the suggested pixel structure, sensitivity was simulated using an optical simulator. As a result, the sensitivity was improved by a maximum of 130% and 160% at wavelengths of 850 nm and 940 nm, respectively, with a pixel size of 1.2 ㎛. Therefore, the proposed pixel structure is useful for NIR sensing without thickening the silicon.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.4112-4112
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• 2001

The feasibility of NIR spectroscopy as a quick and nondestructive method for quality control of uniformity of coating thickness of pharmaceutical tablets was investigated. Near infrared spectra of a set of pharmaceutical tablets with varying coating thickness were measured with a diffuse reflectance fiber optic probe connected to a Broker IFS 28/N FT-NIR spectrometer. The challenging issues encountered in this study included: 1. The similarity of the formulation of the core and coating materials, 2. The lack of sufficient calibration samples and 3. The non-linear relationship between the NIR spectral intensity and coating: thickness. A peak at 7184 $cm^{-1}$ was identified that differed for the coating material and the core material when M spectra were collected at 2 $cm^{-1}$ resolution (0.4 nm at 7184 $cm^{-1}$). The study showed that the coating thickness can be analyzed by polynomial fitting of the peak area of the selected peak, while least squares calibration of the same data failed due to the lack of availability of sufficient calibration samples. Samples of coal powder and solid pieces of coal were analyzed by FT-NIR diffuse reflectance spectroscopy with the goal of predicting their ash content, percentage of volatile components, and energy content. The measurements were performed on a Broker Vector 22N spectrometer with a fiber optic probe. A partial least squares model was constructed for each of the parameters of interest for solid and powdered sample forms separately. Calibration models varied in size from 4 to 10 PLS ranks. Correlation coefficients for these models ranged from 86.6 to 95.0%, with root-mean-square errors of cross validation comparable to the corresponding reference measurement methods. The use of FT-NIR diffuse reflectance measurement techniques was found to be a significant improvement over existing measurement methodologies in terms of speed and ease of use, while maintaining the desired accuracy for all parameters and sample forms.(Figure Omitted).

• 분석과학
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• 제16권2호
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• pp.95-101
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• 2003

본 연구에서는 근적외선 분광분석법 (NIR)을 이용하여 메탄올과 에탄올 혼합액 중의 물의 함량을 비파괴적으로 측정하였다. Photo-diode array 방식의 휴대용 NIR system과 scanning 방식의 NIR spectrometer를 이용하여 두 기기 사이의 calibration 결과를 비교하였다. 알코올 혼합액 중의 물의 함량을 정량분석 하기 위해 부분최소자승회귀분석법 (PLSR : partial least squares regression)을 사용하였다. 그 결과 SEP (standard error of prediction)가 photo-diode array 방식을 사용하였을 때는 0.10%, scanning 방식을 사용하였을 때는 0.12%였다. Calibration 모델의 안정성을 확인하기 위하여 6일 동안 2%의 메탄올을 함유하고 있는 에탄올 용액 중의 물의 함량이 3%, 5% 및 7% 되도록 시료를 조제하여 측정하였다. 두 가지 방식의 NIR 모두 3%이내의 변동계수 (CV : coefficient of variation)로 좋은 결과를 나타내었다. 이번 연구를 통해서 메탄올과 에탄올 혼합액 중의 물의 함량 측정이 근적외선 분광분석법을 이용하여 성공적으로 수행되었고 photo-diode array 방식의 휴대용 NIR 시스템을 이용해서 scanning 방식의 NIR spectrometer를 이용한 결과와 유사한 결과를 얻을 수 있었다.

• 생약학회지
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• 제44권4호
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• pp.344-349
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• 2013

Near infrared spectroscopy (NIRS) combined with multivariate analysis was used to discriminate the geographical origin of Alisma orientale from Korea (n=94) and China (n=72). Two-thirds of samples were selected randomly for the training set, and one-third of samples for the test set. Second derivative was used for the pretreatment of NIR spectra. Partial least square discriminant analysis (PLS-DA) models correctly discriminated 100% of the Korean and Chinese A. orientale samples. These results demonstrate the potential use of NIR spectroscopy combined with multivariate analysis as a rapid and accurate method to discriminate A. orientale according to their geographical origin.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.203-224
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• 2003

In recent years, a miniature spectrometer has been extensively developed due to the combination of fiber optics and semiconductor detector arrays. This type of miniature spectrometer has advantages of low price and robustness because of the capability of mass production and no moving parts are required such as lenses, mirrors and scanning monochromator. In this study, for skin diagnostics, a portable near infrared (NIR) system has been developed using a LlGA microspectrometer, which is photo-diode arrays-type.(omitted)

• 약학회지
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• 제48권3호
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• pp.171-176
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• 2004

This study was described for measuring clinically relevant levels of glucose in undiluted plasma and whole blood by near-infrared (NIR) spectroscopy. Result from an initial measurement of major blood components powder was over-lapped the absorption bands of glucose at 1500-1600 nm. However, the NIR data of blood components were clearly separated by principle component analysis (PCA) space. By the use of partial least squares (PLS) regression, glucose concentrations in undiluted plasma and whole blood could be determined with standard errors of prediction (SEP) of 15 mg/dl and 76 mg/dl, respectively. Although these blood components possessed strong absorption bands that overlapped with the absorption bands of glucose, successful calibration models could be carried out.