• Title/Summary/Keyword: History of Topology

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Prediction of Wear Depth of SG Tube based on Types of Wear Scar (전열관의 마모 체적형상에 따른 마모깊이 예측)

  • Ryu, Ki-Wahn;Kim, Hyung-Jin;Park, Chi-Yong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.475-478
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    • 2005
  • Calculation of wear depth with regard to the wear topology is peformed numerically Four typical wear topology, that is round, crescent, flat, and diamond types are adopted to represent the configuration of wear volume. Diamond and flat types are the most severe topology for wear depth history, whereas round and crescent types have small increasing rate of wear depth to the wear volume. Based on this study we can guess that the most severe wear phenomena happens to be upper side of U-tubes in the KSNP SG, because flat or diamond wear will be generated by the wearing motion between tubes and diagonal, vertical, horizontal strips. The misalignment of tube at the stage of manufacturing or distortion of upper structure due to the thermal expansion or vibration of upper structure such as diagonal, vertical, and horizontal strips will be one of the main causes of flat or diamond wear.

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Modern History of Parabolic Equations on a Riemannian manifold (리이만 다양체에서 포물형 편미분 방정식에 관한 근현대사 고찰)

  • Chang, Jeong-Wook
    • Journal for History of Mathematics
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    • v.24 no.1
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    • pp.31-44
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    • 2011
  • Partial differential equations on a Riemannain manifold is one of the most important areas in differential geometry. In this article, we survey the role of parabolic equations on some of the main results of differential geometry and topology, especially in the modern mathematical history. Also, we introduce some recent research in this area.

History Database Construction for Digital Map Updating System using As-Built Drawings (준공도면을 이용한 수치지형도 갱신시스템의 이력 DB 설계)

  • Yang, Sung-Chul;Kim, Ki-Rack;Yu, Ki-Yun
    • Spatial Information Research
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    • v.17 no.2
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    • pp.183-189
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    • 2009
  • The modification of digital maps because of creation, extinction, and change of topology can be expressed by change of information. But according to complication of society, topology of digital maps and relation with another objects is more complicated. We carry out partial update using as-built drawings to reflect in digital maps efficiently with maintaining accuracy and update. This supplement a weak point of partial update without field surveying. But unlike creation and extinction of file with information or of entire database, when each object is changed, added problem will come like change of raw data and of updating date. So it is necessary that history data about creation, change and extinction of spatial data and attribute data have to be chosen and managed. In this study, we analyze operations of updating system of digital map using as-built drawings, and suggest the history database system.

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R. L. Moore's Moore Method and its meaning in Korea (Robert Lee Moore의 교수법과 한국에서의 의미)

  • Lee, Sang-Gu;Ree, Sang-Wook;Kim, Duk-Sun
    • Journal for History of Mathematics
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    • v.21 no.1
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    • pp.79-96
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    • 2008
  • In early 21st century, universities in Korea has been asked the new roles according to the changes of educational and social environment. With Korea's NURI and Brain Korea 21 project support, some chosen research oriented universities now should produce "teacher of teachers". We look 100 years back America's mathematics and see many resemblances between the status of US mathematics at that time and the current status of Korean mathematics, and find some answer for that. E. H. Moore had produced many good research mathematicians through his laboratory teaching techniques. R. L. Moore was his third PhD students. He developed his Texas/Moore method. In this article, we analyze what R. L. Moore had done through his American School of Topology and Moore method. We consider the meaning that early University of Texas case gives us in PBL(Problem Based Learning) process.

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Efficient Migration of Service Agent in P-Grid Environments based-on Mobile Agent (이동에이전트 기반의 P-그리드 환경에서 서비스 에이전트의 효율적인 이주기법)

  • Kook, Youn-Gyou;Uem, Young-Hyun;Jung, Gye-Dong;Chio, Yung-Geun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.131-134
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    • 2005
  • This paper describes the efficient peer-to-peer migration method of Grid service agent on the mobile agent based P-Grid. The migration mechanism for transmitting service agent upon the service request is based on the peer's logic network topology. The network topologies that this system uses are organized as star topology, ring topology and tree topology, and agents are migrated by the master/slave method and serial/parallel method. The migration method of services is chosen based on the execution range and characteristic of the requested service. Also, the entire execution time of service is affected by the performance of peer that is a part of network topology, and the migration order, Therefore, the system monitors the performance of peers, and determines the migration priority based on analyzing and learning history. The system can reduce service execution time efficiently with decisions of migration method for service agent and priority of peers.

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Hopf's Life and Works (호프의 삶과 업적에 대하여)

  • Ko Kwanseok
    • Journal for History of Mathematics
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    • v.18 no.2
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    • pp.1-8
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    • 2005
  • In this paper, we describe H. Hopf's life and works from the historical point of view. We have a very brief mention of history and results prior to Hopf. He raised the question of the topological implications of the sign of curvature. We discuss his contributions in the field of Riemannian geometry.

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Freudenthal and ICMI (프로이덴탈과 ICM)

  • Kim, Sung-Sook;Khang, Mee-Kyung
    • Journal for History of Mathematics
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    • v.24 no.4
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    • pp.87-96
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    • 2011
  • Hans Freudenthal made important contributions to algebraic topology and geometry. He also made significant contributions in history of mathematics and mathematics education. In the 1970s, his intervention prevented the Netherlands from the movement of "new math". He had a very important role as a founder of realistic mathematics education and became famous internationally by that. Because he raised the profile of ICMI strongly, Bass used the expression 'Freudenthal Era' for the period that Freudenthal was the president of ICMI. Now many mathematics educator agree to use the Freudenthal Era when they mention about the history of ICMI. In this paper, we present on the life of Freudenthal and his contributions for mathematics education, especially ICMI.

2D genus topology of 21-cm differential brightness temperature during cosmic reionization

  • Ahn, Kyung-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.46.2-46.2
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    • 2011
  • Planck is already in active operation, and in a few years a detailed CMB anisotropy map will be compiled, surpassing WMAP both in temperature and polarization. The E mode - E mode autocorrelation power spectrum at large scales contains weak but sizable information on the history of cosmic reionization. We show our latest advance of our own simulation of cosmic reionization that incorporates Pop III stars, and provide a forecast for Planck polarization measurement.

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Ontological Analysis on the Phenomenon of Contemporary Architecture - Focused on the Avant-garde in the End of the 20th Century - (현대건축 현상의 존재론적 해석 - 20세기말 아방가르드를 중심으로 -)

  • Byun, Gye-Sung
    • Journal of architectural history
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    • v.14 no.2 s.42
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    • pp.21-40
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    • 2005
  • The purpose of this study was to analyze the features of the avant-garde architecture in the end of the 20th Century based on the ontology as a metalanguage. In view of the results so for achieved, it is possible to say that the thought of becoming, topology, rhizome thought and the Deleuze's concepts of the fold and the event as ever-changing and evolving at any given time are found in the avant-garde architecture, and the introduction of ontological thought into architectural design encourage hopes for a more natural and existential quality in architecture. However, the avant-garde architecture in the end of the 20th century disclosed the limitation in the architectural expression of ontological thought due to the lack of fully understand on ontology. In conclusion, the ontological approach in architecture offers a new morphological methodology and a new way of programming considering the existential aspect of space through the bricoleur's means leaving the ontological meaning of architecture itself.

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A Phylogenetic Analysis for Hox Linked Gene Families of Vertebrates

  • Kim, Sun-Woo;Jung, Gi-La;Lee, Jae-Hyoun;Park, Ha-Young;Kim, Chang-Bae
    • Animal cells and systems
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    • v.12 no.4
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    • pp.261-267
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    • 2008
  • The human chromosomes 2, 7, 12 and 17 show genomic homology around Hox gene clusters, is taken as evidence that these paralogous gene families might have arisen from a ancestral chromosomal segment through genome duplication events. We have examined protein data from vertebrate and invertebrate genomes to analyze the phylogenetic history of multi-gene families with three or more of their representatives linked to human Hox clusters. Topology comparison based upon statistical significance and information of chromosome location for these genes examined have revealed many of linked genes coduplicated with Hox gene clusters. Most linked genes to Hox clusters share the same evolutionary history and are duplicated in concert with each other. We conclude that gene families linked to Hox clusters may be suggestion of ancient genome duplications.