Watersheds 기반 계층적 이진화를 이용한 단백질 반점 분할 알고리즘

김영호,김정자,김대현,원용관,Kim Youngho,Kim JungJa,Kim Daehyun,Won Yonggwan 한국정보처리학회 2005 정보처리학회논문지B Vol.12 No.3

생물학자가 단백질을 검색하고 분석하기 위해서는 2차원 젤 전기영동(2DGE : Two Dimensional Gel Electrophoresis) 실험을 해야 한다. 실험 결과는 2차원 영상이 생성된다. 2차원 영상에서 단백질 반점의 패턴 분석을 위해 2차원 젤 영상에 펼쳐진 단백질 반점들을 영상처리를 통해 분할하고, 대조 그룹의 단백질 패턴과 비교분석을 통해 밝히고자하는 단백질 반점을 찾아내야 한다. 단백질 반점을 분할하는 알고리즘에 있어서 기존에는 가우시안 함수를 적용하였지만, 최근 들어 형태학 분리개념에 의한 Watersheds 영역기반 분할(Watersheds region-based segmentation) 알고리즘을 활용하고 있다. 그러나 Watersheds 영역기반 분할 알고리즘은 크기가 큰 영상에서 원하는 영역을 신속하게 분할한다는 장점이 있지만, 영상 화소의 그레이 값이 연속적인 경우 실제 반점의 개수 에 비해 과다분할(over-segmentation)되거나 과소분할(under-segmentation)의 문제점을 안고 있다. 이는 마커(marker) 포인트의 설정에 의해 어느 정도 해결할 수 있지만 병합(merge)과 분할(split) 과정을 반복해야 한다. 본 논문은 Watersheds 기반 계층적 이진화 기법을 적용하여 마커 드리븐 Watersheds 영상분할의 문제점을 해결하고자 한다. Biologist must have to do 2DGE biological experiment for Protein Search and Analysis. This experiment coming into being 2 dimensional image. 2DGE (2D Gel Electrophoresis : two dimensional gel electrophoresis) image is the most widely used method for isolating of the objective protein by comparative analysis of the protein spot pattern in the gel plane. The process of protein spot analysis, firstly segment protein spots that are spread in 2D gel plane by image processing and can find important protein spots through comparative analysis with protein pattern of contrast group. In the algorithm which detect protein spots, previous 2DGE image analysis is applies gaussian fitting, however recently Watersheds region based segmentation algorithm, which is based on morphological segmentation is applied. Watersheds has the benefit that segment rapidly needed field in big sized image, however has under-segmentation and over-segmentation of spot area when gray level is continuous. The drawback was somewhat solved by marker point institution, but needs the split and merge process. This paper introduces a novel marker search of protein spots by watersheds-based hierarchical threshold, which can resolve the problem of marker-driven watersheds.

Treadmill에서의 경사로 정상보행에 관한 동작분석

김영호,양길태,문무성,Kim, Youngho,Yang, Giltae,Mun, Museong 대한의용생체공학회 1997 의공학회지 Vol.18 No.1

Kinematic and kinetic studies were performed to investigate the walking characteristics on a treadmill with various slopes at the same speed of 1.25m/sec. Six different slopes of the treadmill were selected . -4%(-$2.3^{\circ}$), 0%($0^{\circ}$), 5%($2.9^{\circ}$), 10%($5.7^{\circ}$), 15%($8.6^{\circ}$), and 20%($11.3^{\circ}$). With increased slopes of the treadmill, both hip and knee flexion angles significantly increased at initial contact, and the maximum hip flexion during swing phase and the maximum knee flexion during stance phase also significantly increased Ankle dorsiflexion angle at initial contact and the maximum dorsiflexion increased with increased slopes. However, the maximum plantarflexion in early swing was slightly reduced with increased slopes. Hip extension in late stance and the maximum knee flexion in early swing was not changed sigilificantly with increased slopes. As for the vertical ground reaction force, compared to the yond level walking, both the first and the second peak forces increased, but the mid-support force decreased.

Coupled Eulerian-Lagrangian (CEL) 방법을 이용한 Dynamically Penetrating Anchor의 동적 거동 분석

김영호,정상섬,Kim, Youngho,Jeong, Sang-Seom 대한토목학회 2014 대한토목학회논문집 Vol.34 No.3

대수심 부유 구조물의 하부기초 기술 중 하나인 dynamically penetration anchor (DPA 또는 흔히 torpedo anchor로 칭함)의 거동특성을 시험결과 및 수치 해석적 접근을 통해 분석하였다. 기존의 유한요소 해석기법으로는 이러한 대수심 anchor 구조물의 거동 특성을 적절히 모사하기 어렵기 때문에 본 연구에서는 이러한 부분을 해결하기 위해 Coupled Eulerian-Lagrangian (CEL) 법을 통해 지반-구조물 사이에서 발생하는 메쉬(mesh)의 distortion 현상 및 경계조건 등의 문제점을 대변형의 관점에서 해결하고자 하였다. 실측치와의 비교를 통해, CEL 기법의 타당성을 검증하였고, 그 결과 본 연구에서 적용한 CEL 기법이 기존 유한요소 기술로는 구현이 불가능한 대수심 anchoring system의 자유낙하에 의한 전반적인 거동 및 지반의 변형특성을 적절히 예측함을 알 수 있었다. 또한 검증된 기법을 바탕으로 dynamic anchor의 거동에 영향을 주는 여러 요소들에 대한 매개변수 연구를 추가로 수행하였다. A fundamental study of the dynamically penetrating anchor (DPA - colloquially known as torpedo anchor) embedded into deep seabed was conducted using measurement data and numerical approaches. Numerical simulation of such a structure penetration was often suffered by severe mesh distortion arising from very large soil deformation, complex contact condition and nonlinear soil behavior. In recent years, a Coupled Eulerian-Lagrangian method (CEL) has been used to solve geomechanical boundary value problems involving large deformations. In this study, 3D finite element analyses using the CEL formulation are carried out to simulate the construction process of dynamic anchors. Through comparisons with results of field measurements, the CEL method in the present study is in good agreement with the general trend observed by in-situ measurements and thus, predicts a realistic large deformation movement for the dynamic anchors by free-fall dropping, which the conventional FE method cannot. Additionally, the appropriate parametric studies needed for verifying the characteristic of dynamic anchor are also discussed.

정수문자열의 δ-근사주기와 γ-근사주기를 찾는 병렬알고리즘

김영호,심정섭,Kim, Youngho,Sim, Jeong Seop 한국정보과학회 2017 정보과학회논문지 Vol.44 No.8

반복적인 문자열은 데이터압축, 생물정보학 등 여러 분야에서 연구되어 왔다. 본 논문에서는 음악서열이나 주가지수와 같이 정수로 표현될 수 있는 문자열에 대한 반복에 대해 연구한다. 최근 정수문자열의 최소 ${\delta}$-근사주기와 최소 ${\gamma}$-근사주기를 찾는 문제들이 소개되었고, 문자열의 길이가 n일 때, 두 문제를 각각 $O(n^2)$ 시간에 해결하는 알고리즘들이 제시되었다. 본 논문에서는 위의 두 문제에 대해 각각 $O(n^2)$개의 스레드를 이용하여 O(n) 시간에 해결하는 병렬알고리즘을 제시한다. 실험결과, n = 10,000일 때, 본 논문에서 제시하는 병렬알고리즘은 순차알고리즘보다 최소 ${\delta}$-근사주기를 계산하는데 약 19.7배, 최소 ${\gamma}$-근사주기를 계산하는데 약 40.08배 빠른 수행시간을 보였다. Repetitive strings have been studied in diverse fields such as data compression, bioinformatics and so on. Recently, two problems of approximate periods of strings over integer alphabets were introduced, finding minimum ${\delta}-approximate$ periods and finding minimum ${\gamma}-approximate$ periods. Both problems can be solved in $O(n^2)$ time when n is the length of the string. In this paper, we present two parallel algorithms for solving the above two problems in O(n) time using $O(n^2)$ threads, respectively. The experimental results show that our parallel algorithms for finding minimum ${\delta}-approximate$ (resp. ${\gamma}-approximate$) periods run approximately 19.7 (resp. 40.08) times faster than the sequential algorithms when n = 10,000.

자유주의 국제정치이론에 대한 비판적 고찰

김영호(Kim, Youngho) 동아시아국제정치학회 2009 국제정치연구 Vol.12 No.1

The study of liberal international relations theories is flourishing with the end of the Cold War. Liberalism was presented as an alternative theory to other international relations theories devised to explain international political reality. This article seeks to explain the emergence and development of liberal international relations theories. It analyzes international perspectives of liberal political thinkers, including John Locke and Immanuel Kant. Their theoretical foundations and peace proposals will be critically analyzed. Woodrow Wilson tried to realize liberal ideals through League of Nations and collective security system. Critical analysis will be made of limits of Wilsonian idealism. This article will analyze integration theory and democratic peace theory which represent new theoretical trends after the failure of idealism. This article will conclude by suggesting the importance of "liberal realism" to overcome the limits of liberalism international relations theories.

Scaling Technique을 이용한 기온과 벼 잎 표면온도의 일중 변화 연구

김영호(Youngho Kim),김영숙(Youngsook Kim),엄기철(Kicheol Eom) 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.10

Effects-driven assay of Iranian heavy crude oil on neuclotide exicision repair system : Multi model approach

Youngho Kim(김영호),Nivedita chatterjee,Hyunho Lee(이현호),Jinhee Choi(최진희) 환경독성보건학회 2017 한국독성학회 심포지움 및 학술발표회 Vol.2017 No.5

문자열의 순위주기 병렬 계산

김영호(Youngho Kim),신유건(Youkun Shin),심정섭(Jeong Seop Sim) 한국정보과학회 2017 한국정보과학회 학술발표논문집 Vol.2017 No.06

성별 및 규칙적인 신체활동 여부에 따른 중년 성인의 건강위험지각

김영호 ( Youngho Kim ),강수진 ( Soojin Kang ),박인경 ( Inkyoung Park ) 한국스포츠심리학회 2016 한국스포츠심리학회지 Vol.27 No.3

Purpose: The study was to identify the differences between individuals` own health risk perceptions and those of others at the same age. Moreover, this study tried to explore the differences in perception bias toward health risks by gender and the physical activity level. Methods: Three hundred fifty questionnaires were initially distributed to company employees and sports center members. Among them, total 332 were finally used in this study(male: 166, female: 166, Mage=49.32 years). Self and other risk judgment profile was revised into Korean and applied in the study. Frequency analysis and independent t-test were carried out by SPSS 23.0. Results: Results indicated that middle-aged adults tend to have unrealistic perceptions of their vulnerability to most health risks and perceive their own likelihood of encountering all health risks events as lower than that of others. In addition, the finding revealed that there were significant differences in perception bias toward to health risks by gender and the physical activity level. Conclusion: The significance of this study lies in the fact that it made a unique contribution to the existing knowledge about middle-aged adults` health risk perceptions.

Alteration of the Nucleotide Excision Repair Pathway by IHC Oil Exposure

Youngho Kim(김영호) 환경독성보건학회 2018 한국독성학회 심포지움 및 학술발표회 Vol.2018 No.6