• 제목/요약/키워드: ${\sigma}-complete$

검색결과 44건 처리시간 0.019초

Precise Rates in Complete Moment Convergence for Negatively Associated Sequences

  • Ryu, Dae-Hee
    • Communications for Statistical Applications and Methods
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    • 제16권5호
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    • pp.841-849
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    • 2009
  • Let {$X_n$, n ${\ge}$ 1} be a negatively associated sequence of identically distributed random variables with mean zeros and positive finite variances. Set $S_n$ = ${\Sigma}^n_{i=1}\;X_i$. Suppose that 0 < ${\sigma}^2=EX^2_1+2{\Sigma}^{\infty}_{i=2}\;Cov(X_1,\;X_i)$ < ${\infty}$. We prove that, if $EX^2_1(log^+{\mid}X_1{\mid})^{\delta}$ < ${\infty}$ for any 0< ${\delta}{\le}1$, then $\lim_{{\epsilon}\downarrow0}{\epsilon}^{2{\delta}}\sum_{{n=2}}^{\infty}\frac{(logn)^{\delta-1}}{n^2}ES^2_nI({\mid}S_n{\mid}\geq{\epsilon}{\sigma}\sqrt{nlogn}=\frac{E{\mid}N{\mid}^{2\delta+2}}{\delta}$, where N is the standard normal random variable. We also prove that if $S_n$ is replaced by $M_n=max_{1{\le}k{\le}n}{\mid}S_k{\mid}$ then the precise rate still holds. Some results in Fu and Zhang (2007) are improved to the complete moment case.

FILTER SPACES AND BASICALLY DISCONNECTED COVERS

  • Jeon, Young Ju;Kim, ChangIl
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제21권2호
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    • pp.113-120
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    • 2014
  • In this paper, we first show that for any space X, there is a ${\sigma}$-complete Boolean subalgebra of $\mathcal{R}$(X) and that the subspace {${\alpha}{\mid}{\alpha}$ is a fixed ${\sigma}Z(X)^{\sharp}$-ultrafilter} of the Stone-space $S(Z({\Lambda}_X)^{\sharp})$ is the minimal basically disconnected cover of X. Using this, we will show that for any countably locally weakly Lindel$\ddot{o}$f space X, the set {$M{\mid}M$ is a ${\sigma}$-complete Boolean subalgebra of $\mathcal{R}$(X) containing $Z(X)^{\sharp}$ and $s_M^{-1}(X)$ is basically disconnected}, when partially ordered by inclusion, becomes a complete lattice.

BIPACKING A BIPARTITE GRAPH WITH GIRTH AT LEAST 12

  • Wang, Hong
    • 대한수학회지
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    • 제56권1호
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    • pp.25-37
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    • 2019
  • Let G be a bipartite graph with (X, Y ) as its bipartition. Let B be a complete bipartite graph with a bipartition ($V_1$, $V_2$) such that $X{\subseteq}V_1$ and $Y{\subseteq}V_2$. A bi-packing of G in B is an injection ${\sigma}:V(G){\rightarrow}V(B)$ such that ${\sigma}(X){\subseteq}V_1$, ${\sigma}(Y){\subseteq}V_2$ and $E(G){\cap}E({\sigma}(G))={\emptyset}$. In this paper, we show that if G is a bipartite graph of order n with girth at least 12, then there is a complete bipartite graph B of order n + 1 such that there is a bi-packing of G in B. We conjecture that the same conclusion holds if the girth of G is at least 8.

6시그마 도입을 통한 EOP 측정시스템 개선 사레연구 : D사의 6시그마 활동 사례를 중심으로 (A Case Study for Improvement of EOP Measurement System through 6 Sigma Introduction)

  • 최천규
    • 품질경영학회지
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    • 제34권3호
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    • pp.51-61
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    • 2006
  • This paper is dealing with a 6 sigma application in chemical industries. The company is enterprise which produce PR that is semiconductor material. CTQ is consisted of thickness (Big Y$_1$) and EOP (Big Y$_2$). After 6 sigma improvement activity that thickness (Big Y$_1$) improved from 0.98 sigma to 2.80 sigma and EOP (Big Y$_2$, energy optimizer) improved from 1.53 sigma to 3.98 sigma. The effectiveness of financial scope reduced 58,200,000 won of COPQ. But there are some problems to enforce 6 sigma in small enterprises. First, it is a lack of complete charge manpower enforcing S sigma activity. Second, it is a lack of professional knowledge of project leaders. Third, the passion of sponsorship (champion) is a lacking. Nevertheless useful tool was certified so that 6 sigma achieves quality reform in small enterprises.

VOLUME PROBLEMS ON LORENTZIAN MANIFOLDS

  • Kim, Seon-Bu
    • 대한수학회논문집
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    • 제10권1호
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    • pp.163-173
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    • 1995
  • Inspired in [2,9,10,17], pp. E. Ehrlich and S. B. Kim in [4] cultivated the Riccati equation related to the Raychaudhuri equation of General Relativity for the stable Jacobi tensor along the geodesics to extend the Hawking-Penrose conjugacy theorem to $$ f(t) = Ric(c(t)',c'(t)) + tr(\sigma(A)^2) $$ where $\sigma(A)$ is the shear tensor of A for the stable Jacobi tensor A with $A(t_0) = Id$ along the complete Riemannian or complete nonspacelike geodesics c.

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ON THE PRECISE ASYMPTOTICS IN COMPLETE MOMENT CONVERGENCE OF NA SEQUENCES

  • Han, Kwang-Hee
    • Journal of applied mathematics & informatics
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    • 제28권3_4호
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    • pp.977-986
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    • 2010
  • Let $X_1$, $X_2$, $\cdots$ be identically distributed negatively associated random variables with $EX_1\;=\;0$ and $E|X_1|^3$ < $\infty$. In this paper we prove $lim_{{\epsilon\downarrow}0}\;\frac{1}{-\log\;\epsilon}\sum\limits_{n=1}^\infty\frac{1}{n^2}ES_n^2I\{|S_n|\;{\geq}\;{\sigma\epsilon}n\}\;=\;2$ and $lim_{\epsilon\downarrow0}\;\epsilon^{2-p}\sum\limits_{n=1}^\infty\frac{1}{n^p}$ $E|S_n|^pI\{|S_n|\;{\geq}\;{\sigma\epsilon}n\}\;=\;\frac{2}{2-p}$ for 0 < p < 2, where $S_n\;=\;\sum\limits_{i=1}^{n}X_i$ and 0 < $\sigma^2\;=\;EX_1^2\;+\;\sum\limits_{i=2}^{\infty}Cov(X_1,\;X_i)$ < $\infty$. We consider some results of i.i.d. random variables obtained by Liu and Lin(2006) under negative association assumption.

Elimination of Idle Tones by a 2-Bit Adaptive Sigma-Delta Modulation System

  • Prosalentis, Evangelos;Tombras, George S.
    • ETRI Journal
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    • 제31권4호
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    • pp.393-398
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    • 2009
  • The operation of a first-order 2-bit adaptive sigma-delta modulation system is described and discussed in this paper. The system operation is based on the combination of both "memory" and "look-ahead" estimation in the employed step-size adaptation algorithm of the basic quantizer. In comparison to simple systems and other adaptive sigma-delta systems, computer simulation results show that these features of the described system are responsible for the high SNR values and the extended dynamic range achieved for AC signals as well as the noise power reduction of almost 10 dB and the complete elimination of the idle tones for DC signals. However, such an advantageous performance requires the least possible multiplicative error accumulation, and this cannot be achieved without analog circuits of the highest possible accuracy.

Complete convergence for weighted sums of arrays of random elements

  • Sung, Soo-Hak
    • 대한수학회지
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    • 제32권4호
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    • pp.679-688
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    • 1995
  • Let $(B, \left\$\mid$ \right\$\mid$)$ be a real separable Banach space. Let $(\Omega, F, P)$ denote a probability space. A random elements in B is a function from $\Omega$ into B which is $F$-measurable with respect to the Borel $\sigma$-field $B$(B) in B.

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INNOVATION FIXED POINT THEOREMS IN 0-σ-COMPLETE METRIC-LIKE SPACES WITH APPLICATION IN INTEGRAL EQUATIONS

  • Ranjbar, Ghorban Khalilzadeh
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제29권3호
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    • pp.231-244
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    • 2022
  • In this paper, we introduce the notion of rational g-h-ϕ-weak contractions in tripled metric-like spaces and demonstrate common fixed point results for each mappings in 0-σ complete tripled metric-like spaces and some examples and application are given.