• Journal of Ginseng Research
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• 제11권1호
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• pp.17-23
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• 1987

인삼에서 생리활성이 보고된 알카로이드 분획에 관한 성분연구의 일환으로 백삼 50kg으로부터 알카로이드 분획 2.6g(수율:$5{\times}10^{-3}$%)을 분리하였으며, $CHCl_3$/MeOH(10 : 1)의 전개용매로 TLC한 결과 약 13종 이상의 Dragendorff 시약에 양성인 spot들을 관찰 할 수 있었다. 인삼 종류별 비교에 있어서는 백삼, 홍삼 및 전칠인삼은 서로 별 차이가 없었지만 미국인삼에 있어 No.2(Rf 0.71), No.3(Rf, 0.68)등의 spot가 검출되지 않았다. 또한 백삼에서 1종의 알카로이드 성분을 순수분리하여 화학적, 분광학적인 방법으로 구조를 구명한바 $N_9$-formyl-1-methyl-$\beta$-carboline으로 동정하였다.

• 디지털산업정보학회논문지
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• 제9권2호
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• pp.111-119
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• 2013

Face recognition has recently become one of the most popular research areas in the fields of computer vision, machine learning, and pattern recognition because it spans numerous applications, such as access control, surveillance, security, credit-card verification, and criminal identification. In this paper, we propose a simple descriptor called an ECSP(Extended Center-Symmetric Pattern) for illumination-robust face recognition. The ECSP operator encodes the texture information of a local face region by emphasizing diagonal components of a previous CS-LBP(Center-Symmetric Local Binary Pattern). Here, the diagonal components are emphasized because facial textures along the diagonal direction contain much more information than those of other directions. The facial texture information of the ECSP operator is then used as the input image of an image covariance-based feature extraction algorithm such as 2D-PCA(Two-Dimensional Principal Component Analysis). Performance evaluation of the proposed approach was carried out using various binary pattern operators and recognition algorithms on the Yale B database. The experimental results demonstrated that the proposed approach achieved better recognition accuracy than other approaches, and we confirmed that the proposed approach is effective against illumination variation.

• 한국멀티미디어학회논문지
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• 제9권1호
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• pp.11-22
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• 2006

얼굴 검출은 개인 인증이나 보안 등 그 응용분야가 다양하여 활발히 연구가 진행되고 있다. 본 논문에서는 분포맵에 기반한 얼굴 검출의 새로운 방법을 제안한다. 제안한 방법은 먼저, 빈도수를 고려한 피부색 분포맵을 입력 영상에 적용하여 일차적으로 얼굴 후보영역을 구하고, 이 영역에서 눈동자색 분포맵을 이용하여 눈후보영역을 결정함으로써 얼굴 구성 요소를 탐색하는 탐색공간을 축소한다. 결정된 눈 후보영역에서 가중치가 있는 윈도우를 이용하여 휘도성분과 색상성분의 상관값을 특징벡터로 한 템플릿 정합 방법으로 눈 후보점을 검출한다. 최종적으로 각 눈 후보점 쌍에 대하여 눈과 입의 위치관계 정보와 입을 인식하는 평가함수를 이용하여 얼굴을 검출하였다. 실험 결과, 제안된 방법은 좋은 성능을 보였다.

• 한국항행학회논문지
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• 제12권6호
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• pp.691-698
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• 2008

본 논문에서는 비디오 검색을 위한 새로운 얼굴 검출 및 인식 방법을 제안한다. 인물 정함은 비디오 프레임에서 어떻게 얼굴을 정확하게 찾아내는가에 달려 있다. 얼굴 영역은 Adaboost 알고리즘으로 부스트된 viola-jones의 특징을 이용하여 비디오 프레임에서 검출한다. 얼굴 검출 후 조명 보정을 하고 PCA(Principal Component Analysis)로 특징점을 추출하고 SVM(Support Vector Machine)으로 사람의 신원을 분류한다. 실험 결과 제안한 방법이 정합율면에서 우수한 성능을 보였다.

• 한국추진공학회지
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• 제12권1호
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• pp.44-50
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• 2008

본 연구에서는 SIMULINK를 이용하여 헬리콥터 추진시스템인 터보축 엔진의 성능모델링을 수행하였고 정확한 성능모델링을 위해 실제 엔진의 성능을 반영할 수 있는 구성품 성능도를 제작사에서 제공된 제한된 성능데이터로부터 유전알고리즘과 시스템 식별을 이용하여 새로이 생성하였다. 제작사에서 제공한 성능데이터와의 비교를 통해 개발한 프로그램의 신뢰성을 검증하였다.

• 한국작물학회지
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• 제44권1호
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• pp.78-85
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• 1999

To investigate kernel hardness, a compression test which is widely used to measure the hardness of individual kernels as a physical testing method was made simultaneously with the measurement of friabilin (15KDa) which is strongly associated with kernel hardness and was recently developed as a biochemical marker for evaluating kernel hardness in 79 Korean wheat varieties and experimental lines. With the scattered diagram based on the principal component analysis from the parameters of the compression test, 79 Korean wheat varieties were classified into three groups based on the principal component analysis. Since conventional methods required large amount of flour samples for analysis of friabilin due to the relatively small amount of friabilin in wheat kernels, those methods had limitations for quality prediction in wheat breeding programs. An extraction of friabilin from the starch of a single kernel through cesium chloride gradient centrifugation was successful in this experiment. Among 79 Korean wheat varieties and experimental lines 50 lines (63.3%) exhibited a friabilin band and 29 lines (36.7%) did not show a friabilin band. In this study, lines that contained high maximum force and the lower ratio of minimum force to maximum force showed the absence of the friabilin band. Identification of friabilin, which is the product of a major gene, could be applied in the screening procedures of kernel hardness. The single kernel analysis system for friabilin was found to be an easy, simple and effective screening method for early generation materials in a wheat breeding program for quality improvement.

• 디지털산업정보학회논문지
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• 제8권2호
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• pp.31-40
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• 2012

Face recognition refers to the process of identifying individuals based on their facial features. It has recently become one of the most popular research areas in the fields of computer vision, machine learning, and pattern recognition because it spans numerous consumer applications, such as access control, surveillance, security, credit-card verification, and criminal identification. However, illumination variation on face generally cause performance degradation of face recognition systems under practical environments. Thus, this paper proposes an novel face recognition system using a fusion approach based on local binary pattern and two-dimensional principal component analysis. To minimize illumination effects, the face image undergoes the local binary pattern operation, and the resultant image are divided into two sub-images. Then, two-dimensional principal component analysis algorithm is separately applied to each sub-images. The individual scores obtained from two sub-images are integrated using a weighted-summation rule, and the fused-score is utilized to classify the unknown user. The performance evaluation of the proposed system was performed using the Yale B database and CMU-PIE database, and the proposed method shows the better recognition results in comparison with existing face recognition techniques.

• Journal of Power Electronics
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• 제16권3호
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• pp.1097-1109
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• 2016

Fault detection and isolation are related to system monitoring, identifying when a fault has occurred, and determining the type of fault and its location. Fault detection is utilized to determine whether a problem has occurred within a certain channel or area of operation. Fault detection and diagnosis have become increasingly important for many technical processes in the development of safe and efficient advanced systems for supervision. This paper presents an integrated technique for fault diagnosis and classification for open- and short-circuit faults in three-phase inverter circuits. Discrete wavelet transform and principal component analysis are utilized to detect the discontinuity in currents caused by a fault. The features of fault diagnosis are then extracted. A fault dictionary is used to acquire details about transistor faults and the corresponding fault identification. Fault classification is performed with a fuzzy logic system and relevance vector machine (RVM). The proposed model is incorporated with a set of optimization techniques, namely, evolutionary particle swarm optimization (EPSO) and cuckoo search optimization (CSO), to improve fault detection. The combination of optimization techniques with classification techniques is analyzed. Experimental results confirm that the combination of CSO with RVM yields better results than the combinations of CSO with fuzzy logic system, EPSO with RVM, and EPSO with fuzzy logic system.

• 한국식품과학회지
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• 제35권4호
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• pp.648-652
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• 2003

본 실험은 순수참기름과 혼합참기름의 구별 및 순도판별을 용이하게 하기 위한 분석방법을 제시하고자 실행되었다. 순수참기름과 옥수수기름을 95 : 5, 90 : 10, 80 : 20(w/w)의 비율로 각각 비율을 달리해서 혼합참기름을 제조한 후 GC, SPME-GC/MS, 전자코를 이용한 분석을 실시하였다. 지방산조성(mole%)을 비교한 결과 옥수수기름이 10%이상 함유된 혼합참기름과 순수참기름 간에는 stearic acid와 linoleic acid의 함량의 변화로 구별이 가능하였으나 5%내로 옥수수유가 함유된 혼합참기름과 순수참기름과의 구별은 용이하지 않았다. 향기성분동정을 위해 SPME-GC/MS 분석을 실시한 결과순수참기름과 혼합참기름은 같은 향기성분 패턴을 보여 구별하기 어려웠다. 반면, MOS 유형의 전자코를 이용하여 향기성분패턴 분석결과 제1주성분 값의 기여율이 98.76%로 구별이 가능하였으며 이로써 신속하고 편리하게 비파괴적 분석 방법인 전자코를 활용하여 순수참기름과 혼합참기름을 구별할 수 있었다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.3-11
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• 2003

We analysed phases recorded by the M$_{L}$ 3.6 Cheolwon, Korea, earthquake occurred on the 10th of December, 2002 and computed source parameters such as hypocenter, origin time, earthquake magnitude and focal solutions. We used PmP and SmS phases to increase the accuracy in determinations of the hypocenter and origin time in addition to the phases such as Pg, Pn, Sg and Sn which are generally used in routine processes. The epicenter, depth, and origin time of the Cheolwon earthquake determined based on data of 11 stations within 200 km from the epicenter are 38.8108$^{\circ}$N, N, 127.2214'E, 11.955 km, and on 7:42:51.436. The earthquake magnitude obtained from all the stations is 3.6 M$_{L}$. The fault plane solution calculated based on data from 19 stations indicates slip process of a normal fault including strike-slip motion. The direction of compressional stress field has a large vertical component and a ESE-WNW direction of horizontal component, which is different from the mainly horizontal direction of main compressional stress field in the Korean Peninsula (ENE-WSW) obtained by previous studies.ies.s.