• Title/Summary/Keyword: persistent

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Topological Analysis of Spaces of Waveform Signals (파형 신호 공간의 위상 구조 분석)

  • Hahn, Hee Il
    • Journal of Korea Multimedia Society
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    • v.19 no.2
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    • pp.146-154
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    • 2016
  • This paper presents methods to analyze the topological structures of the spaces composed of patches extracted from waveform signals, which can be applied to the classification of signals. Commute time embedding is performed to transform the patch sets into the corresponding geometries, which has the properties that the embedding geometries of periodic or quasi-periodic waveforms are represented as closed curves on the low dimensional Euclidean space, while those of aperiodic signals have the shape of open curves. Persistent homology is employed to determine the topological invariants of the simplicial complexes constructed by randomly sampling the commute time embedding of the waveforms, which can be used to discriminate between the groups of waveforms topologically.

Identification of Topological Entities and Naming Mapping for Parametric CAD Model Exchanges

  • Mun, Duh-Wan;Han, Soon-Hung
    • International Journal of CAD/CAM
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    • v.5 no.1
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    • pp.69-81
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    • 2005
  • As collaborative design and configuration design gain increasing importance in product development, it becomes essential to exchange parametric CAD models among participants. Parametric CAD models can be represented and exchanged in the form of a macro file or a part file that contains the modeling history of a product. The modeling history of a parametric CAD model contains feature specifications and each feature has selection information that records the name of the referenced topological entities. Translating this selection information requires solving the problems of how to identify the referenced topological entities of a feature (persistent naming problem) and how to convert the selection information into the format of the receiving CAD system (naming mapping problem). The present paper introduces the problem of exchanging parametric CAD models and proposes a solution to naming mapping.

Supporting Persistent Objects for Geometric Modeling (형상 모델링을 위한 지속성 객체의 관리)

  • Bahn, Duk-Hoon;Lee, Arthur H.
    • Journal of the Korea Computer Graphics Society
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    • v.1 no.2
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    • pp.241-247
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    • 1995
  • 지금까지 개발된 객체 지향 3 차원 그래픽스 툴킷에서 객체의 지속성은 파일 시스템 인터페이스를 통한 일괄 처리 방법에 의해 이루어져 왔다. 이러한 접근 방법은 툴킷 개발자뿐만 아니라 용용 프로그래머 모두에게 파일 처리에 대한 불필요한 부담을 주어 왔다. 툴킷 사용자들의 주된 관심은 하위 레벨 파일 시스템 인터페이스 처리가 아니라 모델링에 관련된 생각들을 표현할 수 있는데 있다. 본 논문에서는 툴킷 수준에서 객체의 지속성을 지원하여 사용자로부터 파일 처리에 대한 부담을 없앨 수 있는 SPORTS (Small Persistent Object system for geometRic objecTS)에 대해서 기술한다. 본 시스템은 특히 형상 모델링을 지원하기 위하여 응용 프로그래머가 효과적으로 저장과 로드 방식을 선택할 수 있도록 설계되었다.

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Measurement of Persistent Toxic Substances in Gosan, Jeju (제주도 고산에서의 미량독성 유해물질 측정)

  • 김영성;김진영;문길주;한진석;김영준;윤순창;김용표;강창희;권성안
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.77-78
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    • 2003
  • 2001년 5월 스톡홀름에서는 92개국이 DDT, 다이옥신 등 12개 잔류성 유기오염물질 (POPs, persistent organic pollutants)의 궁극적 소멸을 목표로, 배출 및 사용 저감을 위하여 유엔협약인 이른바 스톡홀름협약에 서명하였다. 이는 유럽에서 UNECE (United Nations Economic Commissions for Europe) 장거리 이동 대기오염 협약의 일환으로 1998년 6월 덴마크 오후스에서 체결된 POPs에 관한 의정서에 뒤이은 결과이다 1998년 6월 오후스에서는 POPs와 함께 수은, 카드뮴, 납 등 3개 중금속에 관한 의정서가 체결되어 중금속에 관한 향후 국제사회의 동향을 짐작케 하고 있다. (중략)

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GENERALIZED $BARTOSZY\'{N}SKI'S$ VIRUS MODEL

  • Kim, Yong-Dai
    • Journal of the Korean Statistical Society
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    • v.35 no.4
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    • pp.397-407
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    • 2006
  • A new stochastic process is introduced for describing a mechanism of viruses. The process generalizes the $Bartoszy\'{n}ski's$ process ($Bartoszy\'{n}ski$, 1975a, 1975b, 1976) by allowing the stochastic perturbation between consecutive jumps to take into account the persistent infection (the infection without breaking infected cells). It is shown that the new process can be obtained by a weak limit of a sequence of Markov branching processes. Along with the construction of the new process, we study how the stochastic perturbation influences the risk of a symptom in an infected host. For this purpose, the quantal response model and the threshold model are investigated and compared through their induced survival functions.

A Case of Surgical Treatment of Nesidioblastosis in Infancy (영아에서 발생한 췌도모세포증의 외과적 치료 1예)

  • Huh, Young-Soo;Chai, Sang-Chul;Nah, Mok-Chan;Kim, Mi-Jin
    • Advances in pediatric surgery
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    • v.1 no.2
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    • pp.195-199
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    • 1995
  • Nesidioblastosis in one of the causes of hyperinsulinemic hypoglysemia in infancy. The most important goal of treatment for persistent hypoglycemia is the prevention of permanent brain damage. The early surgical management is satisfactory to this goal in nesidioblastosis and maintains normal blood sugar level without administration of drugs or supplement of sugar postoperatively in many cases. We experienced a female infant of 3 months old who has suffered from persistent hypoglysemia due to hyperinsulinism and was suspected nesidioblastosis for its cause clinically. She underwent 95% distal pancreatectomy. The histologic findings of nesidioblastosis was confirmed postoperatively. No postoperative complication was occured and her blood sugar levels were maintained within normal range without medical treatment.

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Physical and Particle Flow Modeling of Shear Behavior of Non-Persistent Joints

  • Ghazvinian, A.;Sarfarazi, V.;Nejati, H.;Hadei, M.R.
    • Proceedings of the Korean Society for Rock Mechanics Conference
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    • 2011.09a
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    • pp.3-21
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    • 2011
  • Laboratory experiments and numerical simulations using Particle Flow Code (PFC2D) were performed to study the effects of joint separation and joint overlapping on the full failure behavior of rock bridges under direct shear loading. Through numerical direct shear tests, the failure process is visually observed and the failure patterns are achieved with reasonable conformity with the experimental results. The simulation results clearly showed that cracks developed during the test were predominantly tension cracks. It was deduced that the failure pattern was mostly influenced by both of the joint separation and joint overlapping while the shear strength is closely related to the failure pattern and its failure mechanism. The studies revealed that shear strength of rock bridges are increased with increasing in the joint separation. Also, it was observed that for a fixed cross sectional area of rock bridges, shear strength of overlapped joints are less than the shear strength of non-overlapped joints.

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