• Title/Summary/Keyword: closure

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A NOTE ON TIGHT CLOSURE AND FROBENIUS MAP

  • Moon, Myung-In
    • Journal of the Korean Mathematical Society
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    • v.34 no.1
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    • pp.13-21
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    • 1997
  • In recent years M. Hochster and C. Huneke introduced the notions of tight closure of an ideal and of the weak F-regularity of a ring of positive prime characteristic. Here 'F' stands for Frobenius. This notion enabled us to play an important role in a commutative ring theory, and other related topics.

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CLOSURE OPERATIONS AND THE DESCENDING CHAIN CONDITION

  • Vassilev, Janet C.
    • Journal of the Korean Mathematical Society
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    • v.54 no.6
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    • pp.1699-1731
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    • 2017
  • In this note, we define and compare some closures which behave somewhat like the radical closure. Using these closures as a starting point allows us to classify all semiprime closures on the nodal curve. Several examples provided show how these closures can differ significantly in the non-Noetherian setting.

ASYMPTOTIC STABILITY OF SOME SEQUENCES RELATED TO INTEGRAL CLOSURE

  • ANSARI-TOROGHY, H.
    • Honam Mathematical Journal
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    • v.24 no.1
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    • pp.1-8
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    • 2002
  • In this paper we will show that if E is an injective module over a commutative ring A, then the sequence of sets $Ass_{A}(A/I^{n})^{*(E)}),\;n{\in}N,$ is increasing and ultimately constant. Also we will obtain some results concerning the integral closure of ideals related to some modules.

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PSEUDO P-CLOSURE WITH RESPECT TO IDEALS IN PSEUDO BCI-ALGEBRAS

  • MOUSSAEI, HOSSEIN;HARIZAVI, HABIB
    • Journal of applied mathematics & informatics
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    • v.38 no.1_2
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    • pp.65-77
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    • 2020
  • In this paper, for any non-empty subsets A, I of a pseudo BCI-algebra X, we introduce the concept of pseudo p-closure of A with respect to I, denoted by ApcI, and investigate some related properties. Applying this concept, we state a necessary and sufficient condition for a pseudo BCI-algebra 1) to be a p-semisimple pseudo BCI-algebra; 2) to be a pseudo BCK-algebra. Moreover, we show that Apc{0} is the least positive pseudo ideal of X containing A, and characterize it by the union of some branches. We also show that the set of all pseudo ideals of X which ApcI = A, is a complete lattice. Finally, we prove that this notion can be used to define a closure operation.

Compressibility Factor Effect on the Turbulence Heat Transfer of Super-critical Carbon Dioxide by an Elliptic-blending Second Moment Closure (타원혼합모형을 이용한 초임계상태 이산화탄소의 압축성계수에 의한 난류열전달 특성)

  • Han, Seong-Ho;Seo, Jeong-Sik;Shin, Jung-Kun;Choi, Young-Don
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.1 s.256
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    • pp.40-50
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    • 2007
  • The present contribution describes the application of elliptic-blending second moment closure to predict the gas cooling process of turbulent super-critical carbon dioxide flow in a square cross-sectioned duct. The gas cooling process under super-critical state experiences a drastic change in thermodynamic and transport properties. Redistributive terms in the Reynolds stress and turbulent heat flux equations are modeled by an elliptic-blending second moment closure in order to represent strongly non-homogeneous effects produced by the presence of walls. The main feature of Durbin's elliptic relaxation second moment closure that accounts for the nonlocal character of pressure-velocity gradient correlation and the near-wall inhomogeneity guaranteed by the elliptic blending second moment closure.

Crack Closure and Growth Behavior of Short Fatigue Cracks under Random Loading (Part I : Details of crack Closure Behavior) (짧은 피로균열의 랜덤하중하의 균열닫힘 및 진전거동 (Part I: 균열닫힘 거동 상세))

  • Lee, Shin-Young;Song, Ji-Ho
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.79-84
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    • 2000
  • Crack closure and growth behavior of physically short fatigue cracks under random loading are Investigated by performing narrow- and wide-band random loading tests for various stress ratios. Artificially prepared two-dimensional, short through-thickness cracks are used. The closure behavior of short cracks under random loading is discussed, comparing with that of short cracks under constant-amplitude loading and also that of long cracks under random loading. Irrespective of random loading spectrum or block length, the crack opening load of short cracks is much lower under random loading than under constant-amplitude loading corresponding to the largest load cycle in a random load history, contrary to the behavior of long cracks that the crack opening load under random loading is nearly the same as or slightly higher than constant-amplitude results. This result indicates that the largest load cycle in a random load history has an effect to enhance crack opening of short cracks.

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Characteristics of Injection Molding in Optical Fiber Splice Closure (광섬유 케이블 접속함체의 사출성형 특성 분석)

  • Choi, Jaeyoung;Hong, Minsung
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.25 no.6
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    • pp.434-439
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    • 2016
  • Optical fiber splice closure serves to protect connection parts from external environment. Moreover, it functions as a connection, junction, and distribution in diverse surroundings such as aerial, underground, duct, and pole. In this research, first, the optical fiber splice closure, its configuration, and the design problem were briefly investigated. Second, the design and application for in-line cable closure were studied to satisfy its construction and technical features. The injection molding conditions and optimal design were conducted to save time and cost during the manufacturing process. Third, methods to minimize loss via of optical fiber cable while strongly fixing optical fiber cable with optical cable holder to prevent fracture were researched, and tests such as perfect air tightness and mechanical and environmental performance were conducted.

Microstructurally sensitive crack closure (微視組織에 敏感한 균열닫힘 현상)

  • 김정규;황돈영
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.10 no.6
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    • pp.898-905
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    • 1986
  • In order to obtain the microstructure improving fatigue crack propagation resistance of steels, fatigue crack propagation behavior of martensite-ferrite dual phase steels is investigated in terms of crack deflection and crack closure. The results obtained are as follows; (1) .DELTA.K$_{th}$ and fatigue crack propagation resistance in low .DELTA.K region increases with increasing hardness of second phase. But the difference of this crack propagation resistance decreases with increasing .DELTA.D. (2) In low .DELTA.K region, crack closure increases with increasing hardness of second phase, when the materials have all the sam volume fractionof second phase, or when yield strengths are similar in all materials. (3) These crack closure can be explained by fracture surface roughness due to crack deflection.n.