• Title/Summary/Keyword: $Theta^*$

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COMPARISON OF TOPOLOGIES ON THE FAMILY OF ALL TOPOLOGIES ON X

  • Kim, Jae-Ryong
    • Journal of the Chungcheong Mathematical Society
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    • v.31 no.4
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    • pp.387-396
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    • 2018
  • Topology may described a pattern of existence of elements of a given set X. The family ${\tau}(X)$ of all topologies given on a set X form a complete lattice. We will give some topologies on this lattice ${\tau}(X)$ using a fixed topology on X and we will regard ${\tau}(X)$ a topological space. Our purpose of this study is to comparison new topologies on the family ${\tau}(X)$ of all topologies induced old one.

A NOTE ON SMOOTH AFFINE VARIETIES

  • SO, KWANG-HO
    • Honam Mathematical Journal
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    • v.1 no.1
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    • pp.15-20
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    • 1979
  • 본(本) 논문(論文)에서는 smooth Affine variety가 미분가능(微分可能) 다양체(多樣體)임을 보임으로써 대수기하학(代數幾何學)이 다양체이론(多樣體理論)과 관련(關聯)됨을 논(論)하였다. $\S1$에서는 affine variety의 차원(次元)과 affine variety의 접공간(接空間)에 대(對)한 정의(正義)와 그에 관련(關聯)된 성질(性質)들을 논(論)하였고 $\S2$에서는 simple point와 국소(局所) 매개변수(媒介變數), 그리고 ${\Theta}_x$에서의 유리함수의 급수(級數) 등(等)을 이용(利用)하여 주정리(主定理)(정리(定理)9)를 증명(證明)하였다.

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Wetting of Galvanised Steel by An Epoxy Adhesive: Effects of Surface Oil

  • Shanahan, M.E.R.;Greiveldinger, M.
    • Journal of Adhesion and Interface
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    • v.3 no.1
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    • pp.20-23
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    • 2002
  • The wetting properties of an uncured epoxy resin on both clean and oiled, galvanised steel have been studied. Since the polymer is very viscous at ambient temperature, and also with an aim to simulate industrial conditions, the spreading of drops of resin during a heating cycle (temperature increase at $10^{\circ}C/min$) was recorded and analysed. On clean steel, a contact angle, ${\theta}$, vs time, t, plot shows sigmoidal behaviour, whereas on the oiled substrate, spreading almost ceases in an intermediate stage. This strange behaviour is attributed to significant oil absorption by the polymer.

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Sequential Estimation of variable width confidence interval for the mean

  • Kim, Sung Lai
    • Journal of the Chungcheong Mathematical Society
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    • v.14 no.2
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    • pp.47-54
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    • 2001
  • Let {Xn, n = 1,2,${\cdots}$} be i.i.d. random variables with the only unknown parameters mean ${\mu}$ and variance a ${\sigma}^2$. We consider a sequential confidence interval C1 for the mean with coverage probability 1-${\alpha}$ and expected length of confidence interval $E_{\theta}$(Length of CI)/${\mid}{\mu}{\mid}{\leq}k$ (k : constant) and give some asymptotic properties of the stopping time in various limiting situations.

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Development and Validation of a Catenary-Pantograph Dynamic Simulation By Using the Finite Element Method (유한요소법을 이용한 전차선로-팬터그래프 동적상호작용 해석 프로그램의 개발 및 검증)

  • Cho, Yong-Hyeon;Kang, Youn-Suk;Lee, Ki-Won
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.593-605
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    • 2006
  • We have developed a catenary-pantograph dynamic simulation program by using the finite element method and verified the accuracy according to the EN 50319. During the validation process, we have reviewed which the time integration methods is proper for this application. among the Newmark method, Wilson theta method and alpha method. We conclude that the alpha method is the best in terms of computation time and accuracy.

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TDR 함수량계의 성토 다짐관리에의 활용

  • Kim, Gyu-Seon;Gwon, Hyeong-Seok
    • Geotechnical Engineering
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    • v.28 no.1
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    • pp.39-44
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    • 2011
  • TDR 함수량계는 전자기파를 이용하여 흙의 밀도와 함수비를 비파괴적으로 신속하게 평가하는 유망한 기술이다. TDR 시험법은 10~20cm 길이의 2~3개의 탐침을 지중에 관입시킨 후 전자기파의 이동시간을 측정하여 유전상수($K_a$)를 산정한다. 제안식을 이용하여 유전상수로부터 체적함수비(${\theta}$)의 산정이 가능하므로, 이 시험법은 흙의 함수비를 측정할 수 있는 비파괴시험 장치로 개발되어 활용되고 있다. 또한, 흙의 종류에 따른 보정상수가 파악되어 있는 경우에는 현장 밀도와 현장 함수비를 동시에 평가할 수 있으므로, TDR 함수량계를 이용하여 성토지만비나 노상토에 대한 신속하고 간편한 다짐관리가 기능하다.

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QUASI-FUZZY EXTREMALLY DISCONNECTED SPACES

  • Lee, Bu-Young;Son, Mi-Jung;Park, Yong-Beom
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.10a
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    • pp.77-82
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    • 1998
  • In this paper, we introduce the concept of quasi-fuzzy extremally disconnectedness in fuzzy bitopological space, which is a generalization of fuzzy extremally disconnectedness due to Ghosh [5] in fuzzy topological space and invetstigate some of its properties using the concepts of quasi-semi-closure, quasi-$\theta$-closure and related notions in a fuzzy bitopological settings.

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Fuzzy control for a flexible arm manipulator

  • Fortuna, L.;LoPresti, M.;Vinci, C.
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1037-1040
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    • 1993
  • In this paper a fuzzy controller for a flexible arm with one degree of freedom is presented. Goal of the control is to drive the manipulator to the position $\theta$0 avoiding the oscillations due the elasticity of the arm. The performances of the fuzzy controller are evaluated through a series of simulations that shows appreciable results both for the transient and the steady behaviour.

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An approach to improving the Lindley estimator

  • Park, Tae-Ryoung;Baek, Hoh-Yoo
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.6
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    • pp.1251-1256
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    • 2011
  • Consider a p-variate ($p{\geq}4$) normal distribution with mean ${\theta}$ and identity covariance matrix. Using a simple property of noncentral chi square distribution, the generalized Bayes estimators dominating the Lindley estimator under quadratic loss are given based on the methods of Brown, Brewster and Zidek for estimating a normal variance. This result can be extended the cases where covariance matrix is completely unknown or ${\Sigma}={\sigma}^2I$ for an unknown scalar ${\sigma}^2$.