• 제목/요약/키워드: Branching

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프레팅 피로에서 2단계 균열성장과 분지 유한요소해석 (Finite Element Analysis of Stage II Crack Growth and Branching in Fretting Fatigue)

  • 정현수;조성산
    • 대한기계학회논문집A
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    • 제39권11호
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    • pp.1137-1143
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    • 2015
  • 프레팅 피로균열의 2단계 성장과 분지, 즉 균열이 경사방향으로 성장하다가 방향을 전환하여 수직방향으로 성장하는 과정을 유한요소법으로 해석하였다. 해석에서 A7075-T6의 프레팅 피로실험자료를 이용하였다. 균열성장방향을 결정하는 기준으로 최대 접선응력확대계수, 최대 접선응력확대계수범위, 최대 균열성장속도의 적용 가능성을 검토하였다. 하나의 기준으로는 분지 전후의 균열성장방향을 모사할 수 없고, 분지 전후에 다른 기준을 적용하면 모사가 가능하였다. 또한 분지가 발생하는 균열 길이를 결정하는 방법도 제시하였다.

LAW OF LARGE NUMBERS FOR BRANCHING BROWNIAN MOTION

  • Kang, Hye-Jeong
    • 대한수학회지
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    • 제36권1호
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    • pp.139-157
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    • 1999
  • Consider a supercritical Bellman-Harris process evolving from one particle. We superimpose on this process the additional structure of movement. A particle whose parent was at x at its time of birth moves until it dies according to a given Markov process X starting at x. The motions of different particles are assumed independent. In this paper we show that when the movement process X is standard Brownian the proportion of particles with position $\leq${{{{ SQRT { t} }}}} b and age$\leq$a tends with probability 1 to A(a)$\Phi$(b) where A(.) and $\Phi$(.) are the stable age distribution and standard normal distribution, respectively. We also extend this result to the case when the movement process is a Levy process.

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Reliability of passive optic splitting devices is compared with fused fiber type optical coupler and planar lightwave guide type optical coupler

  • 최영복;조승현;오민철;김상인;정기태;한권훈
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2003년도 하계학술대회
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    • pp.49-51
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    • 2003
  • This test data informs to compare components from different manufactured coupler type. On the point of reliability, less than 1x8 output branching number, fuse type coupler was more stable than PLC type coupler. But more than 1x8 output branching number, PLC type coupler was more stable. This test data showed critical branching point, on the point of reliability.

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Ordering a Left-branching Language: Heaviness vs. Givenness

  • Choi, Hye-Won
    • 한국언어정보학회지:언어와정보
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    • 제13권1호
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    • pp.39-56
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    • 2009
  • This paper investigates ordering alternation phenomena in Korean using the dative construction data from Sejong Corpus of Modern Korean (Kim, 2000). The paper first shows that syntactic weight and information structure are distinct and independent factors that influence word order in Korean. Moreover, it reveals that heaviness and givenness compete each other and exert diverging effects on word order, which contrasts the converging effects of these factors shown in word orders of right-branching languages like English. The typological variation of syntactic weight effect poses interesting theoretical and empirical questions, which are discussed in relation to processing efficiency in ordering.

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Cell cycle-related kinase is a crucial regulator for ciliogenesis and Hedgehog signaling in embryonic mouse lung development

  • Lee, Hankyu;Ko, Hyuk Wan
    • BMB Reports
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    • 제53권7호
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    • pp.367-372
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    • 2020
  • Cell cycle-related kinase (CCRK) has a conserved role in ciliogenesis, and Ccrk defects in mice lead to developmental defects, including exencephaly, preaxial polydactyly, skeletal abnormalities, retinal degeneration, and polycystic kidney. Here, we found that Ccrk is highly expressed in mouse trachea and bronchioles. Ccrk mutants exhibited pulmonary hypoplasia and abnormal branching morphogenesis in respiratory organ development. Furthermore, we demonstrated that Ccrk mutant lungs exhibit not only impaired branching morphogenesis but also a significant sacculation deficiency in alveoli associated with reduced epithelial progenitor cell proliferation. In pseudoglandular stages, Ccrk mutant lungs showed a downregulation of Hedgehog (Hh) signaling and defects in cilia morphology and frequency during progenitor-cell proliferation. Interestingly, we observed that activation of the Hh signaling pathway by small-molecule smoothened agonist (SAG) partially rescued bud morphology during branch bifurcation in explants from Ccrk mutant lungs. Therefore, CCRK properly regulates respiratory airway architecture in part through Hh-signal transduction and ciliogenesis.

Characterization of Centroceras gasparrinii (Ceramiaceae, Rhodophyta) known as Centroceras clavulatum in Korea

  • Won, Boo-Yeon
    • ALGAE
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    • 제25권2호
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    • pp.71-76
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    • 2010
  • Centroceras gasparrinii is characterized by 1) straight spines, 2) an ovoid gland cell, 3) tetrasporangia with involucral branchlets, and 4) ovoid cortical cells on the first and second cortical initials. A similar Centroceras species with dichotomous habit, "Centroceras clavulatum", has been widely known as a common species of Korean marine flora. However, the species known as "C. clavulatum" in Korea is recognized as C. gasparrinii based on the molecular and morphological evidence. Newly generated sequences of rbcL gene reveal that all taxa of Centroceras from Korea having dichotomous branching pattern are C. gasparrinii. There is 0-0.07% sequence divergence among specimens of C. gasparrinii in Korea. "Centroceras clavulatum" is excluded from Korean flora and C. gasparrinii is included instead of "Centroceras clavulatum". C. gasparrinii also differs from C. distichum in Korea in that it has tetrasporangia with involucral branchlets and dichotomous branching pattern, while C. distichum has immersed tetrasporangia and an alternate branching pattern.

CT 이미지로부터 3차원 모델 생성을 위한 contour 기반 알고리즘 (Contour based Algorithms for Generating 3D Models from CT Images)

  • 류재헌;김현수;이관행
    • 한국정밀공학회지
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    • 제20권4호
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    • pp.174-182
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    • 2003
  • Recently, medical imaging has taken interest on CAD based solution for anatomical part fabrication or finite element analysis of human body. In principle, contours representing object boundary are obtained through image processing techniques. Surface models are then approximated by a skinning method. For this, various methods should be applied to medical images and contours. The major bottleneck of the reconstruction is to remove shape inconsistency between contours and to generate the branching surface. In order to solve these problems, bi-directional smoothing and the composite contour generation method are proposed. Bi-directional smoothing has advantage of removing the shape inconsistency between contours and minimizing shrinkage effect with a large number of iterations. The composite contour by the proposed method ensures smooth transition in branching region.

Query Processing based Branch Node Stream for XML Message Broker

  • Ko, Hye-Kyeong
    • International journal of advanced smart convergence
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    • 제10권2호
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    • pp.64-72
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    • 2021
  • XML message brokers have a lot of importance because XML has become a practical standard for data exchange in many applications. Message brokers covered in this document store many users. This paper is a study of the processing of twig pattern queries in XML documents using branching node streams in XML message broker structures. This work is about query processing in XML documents, especially for query processing with XML twig patterns in the XML message broker structure and proposed a method to reduce query processing time when parsing documents with XML twig patterns by processing information. In this paper, the twig pattern query processing method of documents using the branching node stream removes the twigging value of the branch node that does not include the labeling value of the branch node stream when it receives a twig query from the client. In this paper, the leaf node discovery time can be reduced by reducing the navigation time of nodes in XML documents that are matched to leaf nodes in twig queries for client twig queries. Overall, the overall processing time to respond to queries is reduced, allowing for rapid question-answer processing.

비균일 수렴허용오차 방법을 이용한 분지한계법 개선에 관한 연구 (A Non-Uniform Convergence Tolerance Scheme for Enhancing the Branch-and-Bound Method)

  • 정상진;;최경현;최동훈
    • 대한기계학회논문집A
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    • 제36권4호
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    • pp.361-371
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    • 2012
  • 혼합이산비선형계획법(mixed-discrete nonlinear programming) 문제의 최적화를 위한 대표적인 기법 중에 하나인 분지한계법(branch-and-bound method)은 다른 기법에 비해 강건하지만 분지한계법 내부의 각 노드마다 연속최적화를 수행해야 하기 때문에 많은 함수 계산이 요구되는 것으로 알려져 있다. 이러한 분지한계법의 단점을 극복하기 위하여 크게 두 가지 연구를 수행하였다. 먼저, 분지한계법의 각 노드마다 동일한 수렴허용오차를 설정해주던 기존의 방법을 대체할 수 있는 비균일 수렴허용오차 방법을 제안하였다. 또한 분지한계법에 적용할 수 있는 5 가지 분지순서 방법 중에서 분지한계법의 성능을 가장 극대화할 수 있는 분지순서 방법을 제시하였다. 수렴허용오차 방법과 분지순서 방법들을 각각 선택하여 분지한계법에 적용한 후 7 개의 수학예제와 4 개의 공학예제에 대하여 테스트를 수행한 결과, 제안된 비균일 수렴허용오차 방법과 5 가지 분지순서 방법 중 최소간 격차이법을 분지한계법에 함께 적용할 경우 분지한계법의 성능이 가장 극대화 됨을 확인할 수 있었다.

ON THE ISOSPECTRA AND THE ISOMETRIES OF THE ALOFF-WALLACH SPACES

  • Joe, Do-Sang;Lee, Yoon-Weon;Park, Jin-Sung;Ryu, Jeong-Seog
    • 대한수학회보
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    • 제38권2호
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    • pp.413-425
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    • 2001
  • We use the branching rules on SU(3) to show that if two Aloff-Wallach spaces $M_{k,l}\;and\;M_{k',l'}$ are isospectral for the Laplacian acting on smooth functions, they are isometric. We also show that 1 is the non-zero smallest eigenvalue among all Aloff-Wallach spaces and compute the multiplicities.

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