• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.213-218
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• 2008

동일 지점을 촬영한 위성영상은 위성의 센서나 영상의 취득 시기, 지형의 상태 등에 따라 그 지점에 나타나는 화소값이 일정하지 않다. 이러한 영상은 영상간 모자이크나 변화 탐지 결과에 영향을 미칠 가능성이 높으므로 방사보정(또는 방사정규화)을 통해 화소값의 차이를 최소화시킬 필요가 있다. 본 연구는 선형회귀식을 적용한 상대 방사정규화에 초점을 맞추고 있으며, 선형회귀식 구성에 필요한 PIF(Pseudo Invariant Feature)를 자동으로 추출하기 위해 Ordinal Rank 알고리즘을 적용하였다. 이 방법을 통해 각 밴드별 후보 PIF를 추출하고, 공통으로 해당되는 최종 PIF를 추출할 수 있었다. RMSE(Root Mean Square Error), Dynamic range, Coefficient of variation 등을 통해 방사보정 후의 결과를 평가해보았다. 영상회귀를 이용한 방사보정알고리즘과의 비교를 통해 제안된 알고리즘이 갖는 장점을 확인하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.149-150
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• 2012

This paper presents a shot boundary detection method based on the global decision tree that allows for extraction of boundaries of high variations occurring due to camera breaks from frame difference values. For a start, difference values between frames are calculated through local X2-histogram and normalization. Next, the distances between difference values are calculated through normalization.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.55-60
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• 2011

To investigate effects of Ixeris dentata EtOH ext. on lowering lipid levels and anti-oxidation activity, hyperlipidemic rats were treated with Ixeris dentata EtOH ext. and lipid levels and anti-oxdation activity were measured. The Ixeris dentata EtOH ext. groups showed low concentration of plasma FFA, plasma triglyceride, plasma total cholesterol, and plasma LDL-cholesterol compared to control group. However, concentration of plasma HDLcholesterol was not significantly different among all the treatment groups. The Ixeris dentata EtOH ext. groups showed lower level of liver total cholesterol, liver triglyceride, plasma TBARS, and liver TBARS than those of control group. The Ixeris dentata EtOH ext. groups also showed higher level of GSH-Px activity, SOD activity, and CAT activity than those of control group. Moreover, the Ext. showed lower level of TNF-${\alpha}$, Apo-B, Apo-E, and leptin expression than those of control group. The results in this study shows that the Ixeris dentata EtOH ext. have positive effect in lowering lipid level, and anti-oxidative activity.

• The Journal of Korean Society for Radiation Therapy
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• v.23 no.2
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• pp.97-102
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• 2011

Purpose: IMRT QA using 2Dimensional array detector is carried out with condition for discrete dose distribution clinically. And it can affect uncertainty of evaluation using gamma method. We analyze gamma index variation according to grid size and suggest validate range of grid size for IMRT QA in Hospital. Materials and Methods: We performed QA using OniPro I'mRT system software version 1.7b on 10 patients (head and neck) for IMRT. The reference dose plane (grid size, 0.1 cm; location, [0, 0, 0]) from RTP was compared with the dose plane that has different grid size (0.1 cm, 0.5 cm, 1.0 cm, 2.0 cm, 4.0 cm) and different location (along Y-axis 0 cm, 0.2 cm, 0.5 cm, 1.0 cm). The gamma index variation was evaluated by observing the level of changes in Gamma pass rate, Average signal, Standard deviation for each case. Results: The average signal for each grid size showed difference levels of 0%, -0.19%, -0.04%, -0.46%, -8.32% and the standard deviation for each grid size showed difference levels of 0%, -0.30%, 1.24%, -0.70%, -7.99%. The gamma pass rate for each grid size showed difference levels of 0%, 0.27%, -1.43%, 5.32%, 5.60%. The gamma evaluation results according to distance in grid size range of 0.1 cm to 1.0 cm showed good agreement with reference condition (grid size 0.1 cm) within 1.5% and over 5% in case of the grid size was greater than 2.0 cm. Conclusion: We recognize that the grid size of gamma evaluation can make errors of IMRT QA. So we have to consider uncertainty of gamma evaluation according to the grid size and apply smaller than 2 cm grid size to reduce error and increase accuracy clinically.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.517-517
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• 2013

세포막지질의 산화는 심각한 세포막의 기능저하를 유발하고 심하면 세포를 죽음에 이르게하여 생물학적으로 중요한 지표이다. 세포막지질의 산화는 간접적인 화학적 방법으로 측정하거나, 지질을 추출해내어 질량분석기나 핵자기공명분광기 같은 물리적 방법으로 분석한다. 우리는 이온유도 이차전자 방출계수(${\gamma}$) 변화를 측정하여 세포막지질의 산화를 지질추출 없이 측정할 수 있는지 조사해 보았다. 세포막분리가 쉬운 적혈구를 모델세포로 사용하였고, 다양한 라디칼을 발생시키는 대기압 공기 DBD플라즈마 장치를 이용하였다. 적혈구를 플라즈마에 노출하는 시간으로 산화의 정도에 차이를 만들어 측정값과 비교하였다. ${\gamma}$값은 Auger의 중화이론에 바탕을 둔 이온유도 이차전자 방출빔(${\gamma}$-FIB)장비를 이용하여 측정하였다. 측정결과 적혈구가 산화됨에 따라서 ${\gamma}$값이 증가함을 볼 수 있었고, 동시에 workfunction값이 변화함을 보았으며, 그 결과를 화학적 방법과 비교해 보았다.

• Food Science and Preservation
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• v.22 no.6
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• pp.845-850
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• 2015

The influence of different roasting temperatures, times and extraction methods on the quality characteristics of Omija (Schizandra chinensis) seed oils was investigated. Roasted Omija seeds were divided into five groups based on roasting temperature-time conditions: no roasting (Raw) and roasting [R11: $150^{\circ}C$, 10 min, R12: $150^{\circ}C$, 20 min, R21: $250^{\circ}C$, 10 min, R22: $250^{\circ}C$, 20 min (R22)]. Oils from each of the raw and roasted Omija seeds were obtained by solvent (n-hexane) and press (machine) extraction. The $L^*$ values decreased, but the $a^*$ and $b^*$ values increased with increasing the roasting temperature and time. The $L^*$ values were lower in the press-extracted oils than in the solvent-extracted oils. The peroxide value (POV) of Omija seed oils decreased with increasing the roasting temperature-time values. The POV value was higher in the press-extracted oils than in the solvent-extracted oils. ABTS (2, 2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) radical inhibition of Omija seed oils was higher in the solvent-extracted oils than in the press-extracted oils, but there were no significant differences between the two oils. The four major kinds of fatty acid methyl esters detected in Omija seed oils were methyl butyrate, methyl hexanoate, methyl arachidate, and methyl eicosanoate. In conclusion, Omija seed oils obtained by solvent extraction and at higher roasting temperature-time values were more effective antioxidants.

• Journal of Food Hygiene and Safety
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• v.26 no.1
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• pp.70-75
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• 2011

A new and improved analytical method involving alkaline pyridine extraction was proposed to quantity chlorophyll contents in syrup and candy type chlorella products. The performance of analytical method was compared with the conventional Korea food standard method which involves acetone extraction. The application of sonication chlorophyll extraction form alkaline pyridine sample was also explored. The analytical procedure was validated by evaluating accuracy, precision and reproducibility. For liquid samples, the pyridine extraction method showed higher accuracy and precision compared to acetone extraction method. The CV values of pyridine extract method and the acetone extraction method were 18.82 and 40.0, and the accuracy to theoretical values were 106.3% and 78.1%, respectively. When sonication extraction method was applied to the pyridine extraction, the precision was improved as indicated by reduced CV values from 18.82 to 11.36. The improved performance of pyridine-sonication extraction was also validated by recovery test of chlorophyll that was previously spiked into the sample matrix. For solid matrix, the pyridine extraction method showed better performance in analysis of chlorophyll in solid food matrix (CV = 7.05) compared to conventional acetone extraction method (CV = 30.0). However, the accuracy to theoretical values of pyridine and acetone extraction methods only showed only 62.7% an 40%, respectively. The relatively low accuracy of pyridine extraction method (62.7%) was improved to 99.4% by applying additional sonication extraction method. The improved performance of applying additional sonication extraction was validated by standard deviation, CV values and accuracy to theoretical values.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.20-24
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• 2008

차량에 부착된 CCD 카메라를 이용하여 취득된 도로 주변의 영상에 존재하는 사람의 얼굴을 추출하여 제거하는 처리를 할 경우, 사생활 침해의 문제 없이 사용자들에게 원하는 지역의 도로영상의 제공이 가능해진다. 이 실험의 목적은 차량에서 취득된 도로 주변의 칼라 영상에서 사람의 얼굴을 자동으로 추출하는 기술을 개발하는데에 있다. 도로 주변의 CCD영상에서의 얼굴 추출을 위해, HSI(색상, 채도, 명도) 칼라 모델과 YCrCb 칼라 모델을 사용하여 이들 모델에 임계값을 적용하여 피부색을 검출하였으며, 두 개의 모델을 사용한 결과 효과적인 피부색의 검출이 가능함을 확인할 수 있었다. 검출된 피부색 영역을 연결성과 밝기 차이를 이용하여 클러스터링을 실행하고 이렇게 나뉘어진 각각의 구역들에 구역의 면적, 구역내 존재하는 화소의 개수, 구역의 가로와 세로 비율 그리고 타원조건을 적용하여 얼굴 후보 구역을 결정하였다. 그리고 최종적으로 남겨진 구역을 이진화 하고, 이진화 된 영상 중 검은 부분이 5% 이상일 때 이들을 눈, 코, 입 등으로 간주하여 최종적인 얼굴로 결정하였다. 실험 결과 추출되지 않은 얼굴과 잘못 추출된 구역이 발생했으나, 얼굴에 해당하는 임계값등의 조건을 약화시킬 경우 대부분의 얼굴의 추출이 가능할 것으로 여겨지며, 추출된 구역을 흐리게 처리할 경우 오인식된 부분에 대한 사용자의 거부감도 줄일 수 있을 것 으로 예상된다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.11a
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• pp.63-64
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• 2014

본 논문에서는 Saliency map과 Max Filter를 이용한 영상의 자막영역을 추출 한다. Saliency map은 눈에 띄는 영역, 즉 영상에서 주변영역에 비해 밝기 차이가 심한 영역과 윤곽선에 대한 특징이 강한 영역을 돌출하는 것을 말하며, MaxFilter는 중심 픽셀을 최대 윈도우 값을 사용하는 것으로 극단적인 Impulse Noise를 제거하는데 효과적이며 특히 어두운 스파이크를 제거하는데 유용하게 사용된다. 이 두 가지의 특징들을 이용하여 영상의 자막 영역을 추출한다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1556-1561
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• 2011

The purpose of this study was to investigate antioxidant enzyme activity and vitamin E concentrationin in Sprague-Dawley rat after being fed various extracts of Hizikia fusiforme. There were six experimental groups: control group (C), H. fusiforme ethanol extract group (EtOH), H. fusiforme dichloromethane fraction group ($CH_2Cl_2$), H. fusiforme ethylacetate fraction group (EtOAc), H. fusiforme butanol fraction group (n-BuOH), H. fusiforme water fraction group ($H_2O$). H. fusiforme extracts (400 mg/kg B.W) were orally administrated to the rats every day for 4 weeks. The activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px), and concentrations of malondialdehyde (MDA) and vitamin E in the liver and blood were measured. The activity of SOD in the liver was significantly higher in the $CH_2Cl_2$ and $H_2O$ groups (p<0.05) than in the control and other extract groups. The SOD activity in serum increased significantly in all H. fusiforme groups (p<0.05) compared to the control group and it was also significantly higher in the EtOH and $H_2O$ groups (p<0.05) than in other extract groups. The serum catalase activity increased significantly in the n-BuOH group (p<0.05) compared to the control and other extract groups. The plasma MDA concentration decreased significantly in the n-BuOH and $H_2O$ group (p<0.05) compared to the control group. Serum concentration of ${\alpha}$-tocopherol showed no significant differences in most of the experimental groups, but it was significantly higher in the EtOAc group (p<0.05). The ${\alpha}$-tocopherol concentrations in the liver showed a significant increase in the $CH_2Cl_2$ and $H_2O$ groups (p<0.05) compared to the control and other extract groups. The liver ${\gamma}$-tocopherol concentrations in H. fusiforme extract groups showed a tendency to increase compared to the control group and it was significantly higher in the $H_2O$ group (p<0.05) than in other extract groups. These results suggest that supplementation of water extracts of H. fusiforme extract could be effective in improving the antioxidant system.