• Journal of information and communication convergence engineering
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• v.8 no.2
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• pp.205-211
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• 2010

In this study, a Magnetic stimulation Pulse Train control technique is introduced and applied to Flyback converter operating in discontinuous conduction mode. In contrast to the conventional pulse width modulation control scheme, the principal idea of a Magnetic stimulation Pulse Train is to achieve output voltage regulation using high and low power pulses. The proposed technique is applicable to any converter operating in discontinuous conduction. However, this work mainly focuses on Flyback topology. In this paper, the main mathematical concept of the new control algorithm is introduced and simulations as well as experimental results are presented.

• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.311-315
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• 2013

본 논문에서는 주성분 회귀법과 부분최소자승 회귀법을 비교하여 보여준다. 이 비교의 목적은 선형형태를 보유한 근적외선 분광 데이터의 분석에 사용할 수 있는 적합한 예측 방법을 찾기 위해서이다. 두 가지 데이터 마이닝 방법론인 주성분 회귀법과 부분최소자승 회귀법이 비교되어 질 것이다. 본 논문에서는 부분최소자승 회귀법은 주성분 회귀법과 비교했을 때 약간 나은 예측능력을 가진 결과를 보여준다. 주성분 회귀법에서 50개의 주성분이 모델을 생성하기 위해서 사용지만 부분최소자승 회귀법에서는 12개의 잠재요소가 사용되었다. 평균제곱오차가 예측능력을 측정하는 도구로 사용되었다. 본 논문의 근적외선 분광데이터 분석에 따르면 부분최소자승회귀법이 선형경향을 가진 데이터의 예측에 가장 적합한 모델로 판명되었다.

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.455-456
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• 2008

근적외선 분광법(Near-infrared spectroscopy, NIRS)은 대뇌피질에서의 혈류변화(oxy-, deoxyhemoglobin의 농도변화)를 비침습적으로 측정할 수 있는 방법이다. 본 논문에서는 향후 뇌-컴퓨터 접속기술(Brain computer interface)에 적용하기위한 초기 연구단계로, 쥐의 수염을 자극시 활성화되는 대뇌수염피질 영역에서의 혈류변화 및 전기신호를 동시에 측정하고 두 신호의 패턴을 분석한다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.15-20
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• 2008

Near infrared reflectance spectroscopy (NIRS) is a rapid and accurate analytical method for determining the composition of agricultural products and feeds. This study was conducted to measure anthocyanin contents in black colored soybean by using NIRS system. Total 300 seed coat of black colored soybean samples previously analyzed by HPLC were scanned by NIRS and over 250 samples were selected for calibration and validation equation. A calibration equation calculated by MPLS(modified partial least squares) regression technique was developed in which the coefficient of determination for anthocyanin pigment C3G, D3G and Pt3G content was 0.952, 0.936, and 0.833, respectively. Each calibration equation was applied to validation set that was performed with the remaining samples not included in the calibration set, which showed high positive correlation both in C3G and D3G content file. In case Pt3G, the prediction model was needed more accuracy because of low $R^2$ value in validation set. This results demonstrate that the developed NIRS equation can be practically used as a rapid screening method for quantification of C3G and D3G contents in black colored soybean.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.286-292
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• 2014

Near infrared reflectance spectroscopy (NIRS) is a rapid and accurate analytical method for determining the composition of agricultural products and feeds. This study was conducted to measure baicalin, baicalein, and wogonin contents in Scutellaria baicalensis by using NIRS system. Total 63 samples previously were analyzed by HPLC, which showed baicalin, baicalein, and wogonin contents ranging 4.56 to 13.59%, 0.28 to 5.54%, and 0.50 to 1.63% with an average of 9.66%, 2.09% and 0.52%, respectively. Each sample was scanned by NIRS and calculated for calibration and validation equation. A calibration equation calculated by modified partial least squares(MPLS) regression technique was developed in which the coefficient of determination for baicalin, baicalein, and wogonin content was 0.958, 0.944, and 0.709, respectively. Each calibration equation was applied to validation set that was performed with the remaining samples not included in the calibration set, which showed high positive correlation both in baicalin and baicalein content file. In case of wogonin, the prediction model was needed more accuracy because of low $R^2$ value in validation set. These results demonstrate that the developed NIRS equation can be practically used as a rapid screening method for quantification of baicalin and baicalein contents in Scutellaria baicalensis.

• Current Optics and Photonics
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• v.4 no.1
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• pp.57-62
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• 2020

The selection of anesthetic agent is important in preclinical studies, since each agent affects the systemic hemodynamics in different ways. For that reason, we hypothesized that different anesthetic agents will result in different vaginal hemodynamic response and temperature during sexual arousal, in an animal model. To validate the hypothesis, animal experiments were performed using female rats with two anesthetic agents widely used in preclinical studies: ketamine and isoflurane. Our previously developed near-infrared-spectroscopy-based probe was used to measure the changes of oxyhemoglobin (OHb), deoxyhemoglobin (RHb), and total hemoglobin (THb) concentrations along with temperature from the animal vaginal wall. As a control, saline was administered to both isoflurane- and ketamine-anesthetized animals, and did not show any significant changes in OHb, RHb, THb, or temperature. However, an administration of apomorphine (APO, 80 ㎍/kg) induced increases of OHb (63 ± 28 μM/DPF), RHb (35 ± 20 μM/DPF), and THb (98 ± 49 μM/DPF) in ketamine-anesthetized animals, while decreases of OHb (52 ± 76 μM/DPF) and THb (38 ± 30 μM/DPF) and an increase of RHb (28 ± 51 μM/DPF) were found in isoflurane-anesthetized animals. The vaginal temperature decreased from the baseline in both ketamine-(0.42℃) and isoflurane-(1.22℃)anesthetized animals. These results confirmed our hypothesis, and suggest that a preclinical study monitoring hemodynamic responses under anesthesia should employ an appropriate anesthetic agent for the study.

• Journal of the Korean Chemical Society
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• v.44 no.5
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• pp.410-414
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• 2000

The feasibility of near infrared spectroscopy (NIRS) for the evaluation of the compost pro-duced by composting swine excreta has been investigated. The analytes determined were total nitrogen, total phosphorus, organic matter,total carbon,moisture, Cu, $K_2O$ and $Na_2O$. The ranges of concentration of the cal-ibration samples obtained by the conventional chemical method for each component were 1.30-2.75%, 1.45-4.86%, 7.36-81.5%, 23.0-41.1%, 4.2 the coefficient of variation was 4.38, 5.5, 3.2, 1.5, 10.9, 10.6 and 11.9% for total nitrogen, total phosphorus, organic matter, total carbon, moisture, Cu, $K_2O$ and $Na_2O$,respectively. The overall results showed that NlRS can be used for a non-destructive and rapid determination of the analytes to evaluate the quality of compost samples.

• Applied Biological Chemistry
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• v.37 no.5
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• pp.349-355
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• 1994

The present study was conducted to develop the automatic analytical method for determining moisture, nicotine, reducing sugar and total nitrogen contents and color(L, a, b) value in domestic tobacco leaves using near infrared(NIR) spectroscopy. The results of multiple linear regression analysis between chemical and NIR data showed that NIR spectro-scopy can determine those quality components of tobacco samples in 30 seconds, non-destructively. The results using developed calibrations are summarized as follows; The standard error of prediction(SEP) for moisture, nicotine. total nitrogen, reducing sugar contents and color(L, a, b) value in domestic tobacco leaves was 0.28%, 0.25%, 0.07%, 0.75%, 1.25, 0.44 and 1.07, respectively. In addition, The possibility of developing the cheaper filter type NIR instrument, for quality evaluation in the procurement from leaf tobacco cultivators and process control was investigated.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.31-31
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• 2018

The purpose of this study was to statistically analyze amylose and protein content of rice variety resources collected from China (1,542), Japan (1,409), Korea (413), and India (287). The statistical analysis was conducted using ANOVA and DMRT based on the data obtained from NIRS analysis. The average amylose contents were 18.85% in Japanese, 19.99% in Korean, 20.27% in Chinese, and 25.46% in Indian resources. The average protein contents were 7.23% in Korean, 7.73% in Japanese, 8.01% in Chinese, and 8.17% in Indian resources. The amylose and protein content using ANOVA showed significant differences at the level of 0.01. The F-test for amylose content was 158.34, and for protein content was 53.95 compared to critical value 3.78. The amylose and protein content using DMRT (p<0.01) showed significant difference between countries. The value of statistical treatment was divided into three groups such as $China^a$, $Korea^a$, $Japan^b$, $India^c$ in amylose and $China^a$, $India^a$, $Japan^b$, $Korea^c$ in protein. Japanese resources had the lowest level of amylose contents, whereas, the lowest level of protein content was found in Korean resources compared to other origins. Indian resources showed the highest level of amylose and protein contents. It is recommended that these results could be helpful to future breeding experiments.

• Analytical Science and Technology
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• v.16 no.4
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• pp.277-282
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• 2003

The amount of water for the cultivation of citrus is different based on the growing period. The effect of water stress induces to enhance of sugar accumulation in citrus. The water content in the leaves of citrus can be a index for watering during cultivation. The purpose of this study is to determine the water content of citrus leaves non-destructively by using near infrared spectroscopy (NIRS). Citrus leaves were prepared from 'Okitsu' Satusuma mandarin leaves (Citrus unshiu Marc.) ranging from 20.80 to 69.98% of water content by loss on drying method, and NIR reflectance spectra of citrus leaves were acquired by using a fiber optic probe. It was found that the variation of absorbance band 1450 nm from OH vibration of water depending on the water content change. Partial least squares regression (PLSR) was applied to develop a calibration model over the spectral range 1100-1700 nm. The calibration model predicted the water content for the validation set with a standard errors of prediction (SEP) of 0.97%. In order to validate the developed calibration model, routine analyses were performed using independently prepared citrus leaves. The NIR routine analyses showed good results with those of loss on drying method with a SEP of 0.81%. The rapid and non-destructive determination of the water content in citrus leaves was successfully performed by portable NIR system.