• 제목/요약/키워드: contour analysis

검색결과 756건 처리시간 0.026초

Refinement of Ground Truth Data for X-ray Coronary Artery Angiography (CAG) using Active Contour Model

  • Dongjin Han;Youngjoon Park
    • International journal of advanced smart convergence
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    • 제12권4호
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    • pp.134-141
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    • 2023
  • We present a novel method aimed at refining ground truth data through regularization and modification, particularly applicable when working with the original ground truth set. Enhancing the performance of deep neural networks is achieved by applying regularization techniques to the existing ground truth data. In many machine learning tasks requiring pixel-level segmentation sets, accurately delineating objects is vital. However, it proves challenging for thin and elongated objects such as blood vessels in X-ray coronary angiography, often resulting in inconsistent generation of ground truth data. This method involves an analysis of the quality of training set pairs - comprising images and ground truth data - to automatically regulate and modify the boundaries of ground truth segmentation. Employing the active contour model and a recursive ground truth generation approach results in stable and precisely defined boundary contours. Following the regularization and adjustment of the ground truth set, there is a substantial improvement in the performance of deep neural networks.

민감도를 이용한 최적블랭크 설계법의 CAD 형식으로 표현된 금형에의 적용 (An Application of Optimal Blank Design by Sensitivity Analysis to Stampings of General Shaped parts)

  • 손기찬
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1999년도 추계학술대회논문집
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    • pp.45-48
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    • 1999
  • The optimal blank design method by sensitivity analysis has been applied to the formings of oil-pan, tailored blank and front panel have been chosen as the examples. Die shape is prepared by a commercial CAD system. Excellent results has been obtained between the numerical results and the target contour shapes. Through the investigation, the proposed systematic method of optimal blank design is found to be effective in the practical forming processes.

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민감도법을 이용한 최적블랭크 설계법의 일반적인 모양의 금형에의 적용 (An Application of Optimal Blank Design by the Sensitivity Analysis to the Stampings of General Shaped Parts)

  • 심현보;손기찬;황현태
    • 소성∙가공
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    • 제9권3호
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    • pp.226-232
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    • 2000
  • The optimal blank design method by sensitivity analysis has been applied to the formings of oil-pan, tailored blank and front panel as the examples. Die geometry is prepared by a commercial CAD system. Excellent results has been obtained between the numerical results and the target contour shapes. Through the investigation, the proposed systematic method of optimal blank design is found to be effective in the practical forming processes.

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벌류트 압축기내의 난류유동 수치해석 (Numerical Analysis of Turbulent Flows in the Scroll Volute of Centrifugal Compressor)

  • 곽승현
    • Journal of Advanced Marine Engineering and Technology
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    • 제31권6호
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    • pp.681-686
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    • 2007
  • The flow analysis was made by applying the turbulent models in the scroll volume of centrifugal compressor. The $k-{\varepsilon}.\;k-{\omega}$, Spalart-Allmaras and reynolds stress models are used in which the hybrid grid is applied for the simulation. The velocity vector the Pressure contour. the change of residual along the iteration number. and the dynamic head are simulated by solving the Navier-Stokes equations for the comparison of four example cases.

대용량 데이터베이스를 이용한 한국어 운율 특성에 관한 연구 (A Prosodic Study of Korean Using a Large Database)

  • 김종진;이숙향
    • 한국음향학회지
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    • 제24권2호
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    • pp.117-126
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    • 2005
  • 본 연구는 대용량 데이터베이스 분석을 통한 한국어의 운을 특성 규명을 시도하였다. 남녀 화자 1명씩 각각 낭독한 650개의 뉴스기사 문장 (총 1,300 개)은 분절음 레이블링과 운율 레이블링을 한 후, 각 운율단위의 성조유형과 크기, 상위운율단위의 크기와 하위 운율단위 수간의 상관관계, 그리고 강세구의 하강곡선과 상승곡선의 기울기와 F0 값에 대한 비교분석을 수행하였다. 운율단위의 지속시간, 어절수, 음절수와 하위 운율단위의 수는 화자뿐만 아니라 운율단위 위치에 따라서 차이를 보였으며 하위 운율단위의 수는 상위 운율단위의 음절수와 지속시간과 높은 상관관계를 보였다. 강세구 내의 하강곡선의 기울기는 강세구 음절수와 반비례 관계를 보였으며 강세구 첫 성조의 유형에 따라 기울기 값에 차이가 있었다. 이 차이는 고성조로 시작한 강세구 성조의 F0 상승과 성조 간 상승 폭의 차이로 설명할 수 있었다. 강세구 경계의 하강곡선은 일정하면서 강세구 내의 하강곡선에 비해 다소 급격한 기울기를 보였다. 강세구 내의 두 상승곡선은 유사한 기지값을 보였으나 강세구 시작 상승곡선의 F0 변화량이 끝 상승곡선의 F0 변화량보다 크게 나타났다. 그리고 하나의 상승곡선이 강세구를 이루는 L Ha의 경우에는 강세구의 음절수에 반비례 관계를 보였다.

표준한국어 악센트의 실험음성학적 연구 -청취 테스트 및 음향분석- (The Experimental Phonetic Study of Word Accent in Standard Korean)

  • 성철재
    • 대한음성학회지:말소리
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    • 제21_24호
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    • pp.43-89
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    • 1992
  • In this thesis, the prominent aspect of word accent in standard Korean is studied by auditory test and acoustic analysis experiment. The definition of 'accent' is, following Hoyoung Lee's discussion(1990), to be described as 'the means whereby a focused part of an utterance is made to stand out in order to concentrate the hearer's attention on it.' That is to say, the ten of 'accent' may be described in terms of phonological phenomenon and the accented syllable can be phonetically prominent as the result of those phonological process. Prosodic features may have different characteristics in different languages whether they contain linguistically important functions or not. Thus the characteristics of word accent in standard Korean will be determined as the content and trait of prosodic features. Following this viewpoint, present study looked over prosodic features which may effect the characteristics of word accent in standard Korean, through systematic experimental procedure. And the result of this experiment has been verified by statistical method, the T-test, for the purpose of identifying the relatedness among prosodic features(parameters). This thesis, therefore, aimed to investigate the intrinsic acoustic and physical qualities of the word accent in standard Korean. Nonsense words composed by 'mal' and 'ma' which can be divided into 'heavy syllable' and 'light syllable' quoted from Hyman(1975) have been classified into 28 types with respect to syllable numbers(2 syl., 3 sy1., 4 syl.) and these words have become the target of auditory test and acoustic experiment. As the result of those experimental Procedures, the word accent in standard Korean may be said that it has a tendency of fixing first two syllables regardless of syllable numbers. The syllable types of HH, HL, LL in the first two syllables may be prominent at first syllable and the type of H may be at second syllable. Various prosodic features(parameters) including duration, intensity, and Fo(purely phonetic terms) were also strengthened in those positions. The result of this experiment can be cleared up like these : 1. The most important feature is proved as 'duration', the feature of intensity resulted in more subsidiary one than the feature of duration. 2. Fo( fundamental frequency) could be observed as having some coherent contour through almost all syllable types(99 %), that is, in 2 syllable types, it had rising contour, in 2 syllable types, rising-falling contour, and in 4 syllable types, it contained rising-falling-rising contour. The result of auditory test was different with those contour forms of all Fo surveyed. With respect to these results, the discuss for Fo is determined' to be excluded comparing other features. 3. Finally, this thesis resulted in a decision that the word accent in standard Korean may has fixed(somewhat weaker) accent, especially fixed at first two syllables in almost all words. 4. Various kinds of syllable types related with 2,3,4 syllables, therefore, can be reclassified into 4 types of HH, HL, LH, LL following the concept of accent fixing placement(i.e. first two syllables). In these 4 types, the types of HH, HL, LL were prominent at the position of the first syllable , and the type of LH was prominent at the second syllable otherwise.

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DEM 표준오차를 고려한 TIN 구축의 효용성 분석에 관한 연구 (The efficiency analysis of TIN construction considering DEM standard error)

  • 이근상;채효석;조기성
    • Spatial Information Research
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    • 제11권1호
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    • pp.23-32
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    • 2003
  • GIS분야에서 불규칙삼각망은 저수량계산, 지형분석 등에 활용되며 표고, 경사, 방향 정보를 가지고 있기 때문에 처리시간과 용량이 많이 소요된다. 등고선을 활용하여 TIN을 구축하는 과정에서, 선의 단순화를 위해 사용하는 weed tolerance는 등고선상의 샘플 간격에 영향을 미치게 된다. 본 연구에서는 다양한 크기의 weed tolerance에 따른 TIN의 처리시간과 용량을 계산하였으며, 적절한 weed tolerance를 제시하기 위해 TIN으로부터 생성된 수치표고모형의 표준오차를 평가하여 허용오차 범위를 만족하는 weed tolerance를 결정하였다. 평가결과, DEM 표준오차 5m를 만족하는 TIN의 weed tolerance 는 70m였으며, DEM의 해상도는 20m로 나타났다.

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Fusarium속에서 PFGE를 이용한 Electrophoretic Karyotyping (Electrophoretic Karyotyping by PFGE in the Genus Fusarium)

  • 민병례;정진숙;최영길
    • 한국균학회지
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    • 제26권2호통권85호
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    • pp.135-143
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    • 1998
  • CHEF (Contour-Clamped homogeneous electric field) gel electrophoresis를 이용하여 Fusarium section Sporotrichiella, Liseola, Gibbosum, Discolor와 Martiella에 속하는 10종의 electrophoretic karyotype을 비교하였다. Intact chromosomal DNA는 균류의 원형질체로부터 추출하였으며, 크기에 따라 다양한 조건을 주어 DNA 분자를 분리시켰다. Fusarium속에 속하는 종의 염색체는 0.78Mb에서 7.20Mb의 크기를 가진 염색체가 종에 따라 $5{\sim}13$개였다. 각 종의 total genome 크기는 18.32Mb에서 48.20Mb였다. Electrophoretic karyotype을 비교한 후 F. oxysporum formae speciales lilii로부터 무작위로 선택하여 만든 genomic DNA를 probe로 하여 Southern hybridization 분석을 수행하였다.

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내진 보강된 철골모멘트골조의 취약성 등고선을 통한 성능평가 (Performance Evaluation of Steel Moment Resisting Frames with Seismic Retrofit Using Fragility Contour Method)

  • 김수동;이기학;정성훈;김도현
    • 한국지진공학회논문집
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    • 제17권1호
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    • pp.33-41
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    • 2013
  • Due to a high level of system ductility, steel moment resisting frames have been widely used for lateral force resisting structural systems in high seismic zones. Earthquake field investigations after Northridge earthquake in 1994 and Kobe earthquake in 1995 have reported that many steel moment resisting frames designed before 1990's had suffered significant damages and structural collapse. In this research, seismic performance assessment of steel moment resisting frames designed in accordance with the previous seismic provisions before 1990's was performed. Buckling-restrained braces and shear walls are considered for seismic retrofit of the reference buildings. Increasing stiffness and strength of the buildings using buckling-restrained braces and shear walls are considered as options to rehabilitate the damaged buildings. Probabilistic seismic performance assessment using fragility analysis results is used for the criteria for determining an appropriate seismic retrofit strategy. The fragility contour method can be used to provide an intial guideline to structural engineers when various structural retrofit options for the damaged buildings are available.

Analysis of sliding/Impacting Wear in T7be to Convex Spring Contact and Relevant Contact Problem

  • Kim, Hyung-Kyu;Lee, Young-Ho;Heo, Sung-Pil;Jung, Youn-Ho;Ha, Jae-Wook;Kim, Seock-Sam;Jeon, Kyeong-Lak
    • KSTLE International Journal
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    • 제3권1호
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    • pp.60-67
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    • 2002
  • Wear on the tube-to-spring contact is investigated experimentally, The vibration of the tube causes the wear while the springs support it As for the supporting conditions, the contacting normal farce of 5 N,0 N and the gap of 0.1 mm are applied. The gap condition is for considering the influence of simultaneous impacting and sliding on wear. The wear volume and depth decreases in the order of the 5 N,0 N and the gap conditions. This is explained from the contact geometry of the spring, which is convex of smooth contour, The contact shear force is regarded smaller in the case of the gap existence compared with the other conditions. The wear mechanism is considered from SEM observation of the worn surface. The variation of the normal contact traction is analysed using the finite element analysis to estimate the slip displacement range on the contact with consulting the fretting map.