임신중, 후반기와 분만후 좌심실수축기 시간간격에 대한 연구

장경식,외5인 대한순환기학회 1981 Korean Circulation Journal Vol.11 No.2

江原大學校 林科大學 演習林 氣象報告

張京植 江原大學校 林科大學 演習林 1995 演習林硏究報告 Vol.15 No.-

Active Shape 모델과 Gaussian Mixture 모델을 이용한 입술 인식

장경식,이임건 한국정보과학회 2003 정보과학회논문지 : 소프트웨어 및 응용 Vol.30 No.5

In this paper, we propose an efficient method for recognizing human lips. Based on Point Distribution Model, a lip shape is represented as a set of points. We calculate a lip model and the distribution of shape parameters using Principle Component Analysis and Gaussian mixture, respectively. The Expectation Maximization algorithm is used to determine the maximum likelihood parameter of Gaussian mixture. The lip contour model is derived by using the gray value changes at each point and in regions around the point and used to search the lip shape in a image. The experiments have been performed for many images, and show very encouraging result. 이 논문은 입술의 형태를 효과적으로 인식하는 방법을 제안하였다. 입술은 PDM(Point Distribution Model)을 기반으로 점들의 집합으로 표현하였다. 주성분 분석법을 적용하여 입술 모델을 구하고 모델에서 사용하는 형태계수의 분포를 GMM(Gaussian Mixture Model)을 이용하여 구하였다. 이 과정에서 계수를 정하기 위하여 EM(Expectation Maximization) 알고리듬을 사용하였다. 입술 경계선 모델은 입술을 구성하는 각 점과 주변 영역에서의 화소간 변화를 이용하여 구성하였으며 입술 탐색시 사용되었다. 여러 영상을 대상으로 실험한 결과 좋은 결과를 얻었다.

변분다중스케일법을 이용한 Ret=180 채널 난류 유동의 대와류모사

장경식,이보현,윤범상,이주성,노명일 한국전산유체공학회 2010 한국전산유체공학회지 Vol.15 No.2

In the present work, LES with new variational multiscale method is conducted on the fully developed channel flow with Reynolds number, 180 based on the friction velocity and the channel half width. Incompressible Navier-Stokes equations are integrated using finite element method with the basis function of NURBS. To solve space-time equations, Newton's method with two stage predictor multicorrector algorithm is employed. The code is parallelized using MPI. The computational domain is a rectangular box of size 2π×2×4/3π in the streamwise, wall normal and spanwise direction. Mean velocity profiles and velocity fluctuations are compared with the data of DNS. The results agree well with those of DNS and other traditional LES.

1958年 韓國에 流行한 流行性夏季腦炎의 疫學的 考察

張慶植,韓膺洙,李炳學 최신의학사 1959 最新醫學 Vol.2 No.12

Introduction It was noted that the epidemic of Japanese type B encephalitis in Korea has shown periodicity that svery three years a small epidemic and every nine years a large epidemic have been observed. In 1958, there were 6,856 cases and 2, 166 deaths repvted. The report covers of epidemiological investgation of 1958, epidemic o! Japanese type B encep Lialitis. Summary 1. Most cases were reported in the months of August and September and the peak of epidemic is !ate of Augusta 2. Nearly two thirds of total reported cases were from Chulla Namdo, Chulla Pukto, Kyongsang Namdo, and Kyongsang Pukto. 3. Majority of cases reported were under the - age of 20 years and most frequently 4 to 5 years old children were infected. 4. Number of patient by sex was strikingly different and male was twice many of female cases. 5. It was observed that there close correlation between climatological facts and epidemic of the disease. 6. Although further investigation and follow up is needed, the effectiveness of formalized virus vaccne prepared from mouse brain was proved to be effectie. 7. In general epidemiological features of this disease in Korea are similar* to that of other countries like Formosa and japan.

연속 영상에서 강인한 얼굴 및 얼굴 특징 추적

장경식,이찬희,Jang, Kyung-Shik,Lee, Chan-Hee 한국정보통신학회 2010 한국정보통신학회논문지 Vol.14 No.9

AAM(Active Appearance Model)은 변형 가능한 형태의 검출에 가장 효과 적인 방법의 하나이며, 수학적으로 최적화 문제이다. 비용함수는 최소자승 함수이어서 볼록 함수이나, 탐색 공간이 볼록공간이 아니므로 국소 최소값이 전역 최소값인 것으로 보장 되지 않는다. 즉 초기값이 전역 최소값 근방에서 출발하지 않으면, 지역 최소값에 수렴하여 정확한 얼굴 윤곽 검출이 어려워진다. 본 논문에서는 연속적인 입력영상에 SIFT(Scale Invariant Feature Transform)와 유전자 알고리즘을 사용하여 눈동자를 검출하고 AAM 모델의 초기화 정보로 사용함으로써 조명과 배경에 강인한 AAM 기반의 얼굴 정합 방법을 제안한다. 실험을 통하여 제안한 AAM 기반 얼굴 정합 방법이 자세, 얼굴 배경 등에 대해 기존의 AAM 기반 얼굴 정합 방법보다 더 강인한 것으로 확인 되었다. AAM(Active Appearance Model) is one of the most effective ways to detect deformable 2D objects and is a kind of mathematical optimization methods. The cost function is a convex function because it is a least-square function, but the search space is not convex space so it is not guaranteed that a local minimum is the optimal solution. That is, if the initial value does not depart from around the global minimum, it converges to a local minimum, so it is difficult to detect face contour correctly. In this study, an AAM-based face tracking algorithm is proposed, which is robust to various lighting conditions and backgrounds. Eye detection is performed using SIFT and Genetic algorithm, the information of eye are used for AAM's initial matching information. Through experiments, it is verified that the proposed AAM-based face tracking method is more robust with respect to pose and background of face than the conventional basic AAM-based face tracking method.

형태와 가중치 벡터를 이용한 눈동자와 입술 검출

장경식,Jang, kyung-Shik 한국정보과학회 2002 정보과학회논문지 : 소프트웨어 및 응용 Vol.29 No.5

In this paper, we propose an efficient method for recognizing pupils and lip in a human face. Pupils are detected by a cost function, which uses features based on the eye's shape and a relation between pupil and eyebrow. The inner boundary of lip is detected by weighted vectors based on lip's shape and on the difference of gray level between lip and face skin. These vectors extract four feature points of lip : the top of the upper lip, the bottom of the lower lip, and the two corners. The experiments have been performed for many images and show very encouraging result. 이 논문은 눈동자와 입술을 효과적으로 인식하는 방법을 제안하였다. 얼굴에서 가장 어두운 부분 중의 하나인 눈동자와 밝은 부분인 흰자위로 구성되는 눈의 형태적인 특징과 눈동자와 눈썹 사이의 관계를 반영하는 평가함수를 이용하여 눈동자를 인식하였다. 입술 형태, 입술과 인접한 피부와의 밝기 차이를 반영하는 가중치 벡터들을 사용하여 두 입술 사이의 경계선과 입술의 4개 특징점(양 끝점 및 위와 아래의 끝점)을 찾았다. 여러 영상들에 대해 실험하여 좋은 결과를 얻었다.

Proto-oncogene Pokemon in thyroid cancer: a potential promoter of tumorigenesis in papillary thyroid carcinoma

장경식,도성임,김경은,채승완,도인구,이현주,김동훈,손진희 대한병리학회 2021 Journal of Pathology and Translational Medicine Vol.55 No.5

Background: Pokemon is an oncogenic transcription regulator that plays a critical role in cellular differentiation. Although it has been found to be overexpressed in several types of cancer involving different organs, its role in thyroid gland has yet to be reported. The objective of this study was to evaluate the expression of Pokemon in papillary thyroid carcinoma (PTC) based on clinicopathological parameters.Methods: Tissue microarray samples derived from patients with PTC or benign thyroid disease were used to evaluate Pokemon expression based on immunohistochemical analysis. Correlations of its expression with various clinicopathological parameters were then analyzed.Results: Pokemon expression was observed in 22.0% of thyroid follicular cells from the normal group, 44.0% from the group with benign thyroid diseases, and 92.1% from the group with PTC (p < .001). The intensity of Pokemon expression was markedly higher in the PTC group. Pokemon expression level and PTC tumor size showed an inverse correlation. T1a tumors showed strong expression levels of Pokemon. However, larger tumors showed weak expression (p = .006).Conclusions: Pokemon expression is associated with tumorigenesis of PTC, with expression showing an inverse correlation with PTC tumor size. This might be related to the negative regulation of aerobic glycolysis by Pokemon.

극좌표계 변환과 AdaBoost를 이용한 회전 얼굴 검출

장경식,Jang, Kyung-Shik 한국정보통신학회 2021 한국정보통신학회논문지 Vol.25 No.7

회전된 얼굴 검출은 많은 응용 분야에서 필요하지만 회전에 따른 얼굴 모양의 큰 변화로 인해 여전히 어려운 분야이다. 이 논문에서는 회전의 영향을 받지 않는 극좌표 변환 방법과 변환된 영상을 이용하여 회전얼굴을 효과적으로 검출하는 방법이 제안되었다. 제안한 극좌표계 변환 방법은 회전 각도와 무관하게 눈, 입 등과 같은 얼굴 구성 요소들의 위치가 항상 유지되기 때문에 얼굴 구성요소들 간의 공간 정보가 유지되며, 이로 인해 회전 효과가 제거된다. 극좌표계 변환된 영상을 정면 얼굴 검출에 사용되는 AdaBoost를 이용하여 학습하고 회전 얼굴을 검출하였다. 비얼굴 영상을 LBP를 이용하여 학습하고 검출한 얼굴을 검증하였다. BioID 데이터베이스에 있는 영상을 회전하여 얻은 3600개 얼굴영상에 대한 실험 결과 96.17%의 회전얼굴 검출률을 얻었다. 또한, 다수의 회전 얼굴이 포함된 배경이 있는 영상에서 회전 얼굴들을 정확하게 검출하였다. Rotated face detection is required in many applications but still remains as a challenging task, due to the large variations of face appearances. In this paper, a polar coordinate transform that is not affected by rotation is proposed. In addition, a method for effectively detecting rotated faces using the transformed image has been proposed. The proposed polar coordinate transform maintains spatial information between facial components such as eyes, mouth, etc., since the positions of facial components are always maintained regardless of rotation angle, thereby eliminating rotation effects. Polar coordinate transformed images are trained using AdaBoost, which is used for frontal face detection, and rotated faces are detected. We validate the detected faces using LBP that trained the non-face images. Experiments on 3600 face images obtained by rotating images in the BioID database show a rotating face detection rate of 96.17%. Furthermore, we accurately detected rotated faces in images with a background containing multiple rotated faces.

사상체질 진단을 위한 얼굴인상 분류

장경식,Jang, Kyung-Shik 한국정보통신학회 2008 한국정보통신학회논문지 Vol.12 No.1

이 논문에서는 정면 얼굴 영상을 대상으로 사상체질 판정에 사용되는 얼굴 인상을 효과적으로 판정하는 방법을 제안하였다. 판정을 위하여 눈, 턱 형 태 등에 대한 특징을 정의하고 사용하였다. 주성분 분석법을 이용하여 주어진 특징 데이터의 차원을 축소하여 표현하고, 특징 벡터 사이의 클래스 분리를 최대로 하는 선형 변환인 선형 판별 분석법을 수행한 후 SVM을 이용하여 8가지 종류의 인상을 판정하였다. 여러 얼굴 영상에 대해 실험한 결과, 전문가인 한의사가 판정한 결과를 기준으로 약 85.3% 정확도를 가지는 판정결과를 얻었다. In this paper, we propose an efficient method to classify human facial impression using frontal face image. The features that represent the shape of eye, jaw and face are used. The proposed method employs PCA, LDA and SVM in series. PCA is used to project the feature space to a low dimensional subspace. LDA produces well separated classes in a low dimensional subspace even under severe variation. This results in good discriminating power for classification. SVM is used to classify the data. Human face has been classified for 8 facial impressions. The experiments have been performed for many face images, and show encouraging result.