• Title/Summary/Keyword: $L_1$-approximation

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ON THE LEBESGUE SPACE OF VECTOR MEASURES

  • Choi, Chang-Sun;Lee, Keun-Young
    • Bulletin of the Korean Mathematical Society
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    • v.48 no.4
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    • pp.779-789
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    • 2011
  • In this paper we study the Banach space $L^1$(G) of real valued measurable functions which are integrable with respect to a vector measure G in the sense of D. R. Lewis. First, we investigate conditions for a scalarly integrable function f which guarantee $f{\in}L^1$(G). Next, we give a sufficient condition for a sequence to converge in $L^1$(G). Moreover, for two vector measures F and G with values in the same Banach space, when F can be written as the integral of a function $f{\in}L^1$(G), we show that certain properties of G are inherited to F; for instance, relative compactness or convexity of the range of vector measure. Finally, we give some examples of $L^1$(G) related to the approximation property.

The comparison of electron transport coefficients of gases for analysis of multi-term approximation of the Boltzmann equation (다항근사 볼츠만 방정식의 타당성 검토를 위한 가스의 전자수송계수 비교)

  • Song, Byoung-Doo;Ha, Sung-Chul;Jeon, Byoung-Hoon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05e
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    • pp.69-72
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    • 2003
  • This paper describes the information for the difference between two-term and multi-term approximation of the Boltzmann. In previous paper, we calculated the electron transport coefficients in pure Oxygen and Argon gases by using two-term approximation of Boltzmann equation. Therefore, in this paper, we calculated the electron transport coefficients(W and $N{\cdot}D_L$) in pure Oxygen and Argon gases for range of E/N values from 0.01~500[Td] at the temperature was 300[K] and pressure was 1[Torr] by using multi-term approximation of the Boltzmann equation by Robson and Ness, The results of two-term and multi-term approximation of the Boltzmann equation has been compared with the experimental data for a range of E/N.

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The metric approximation property and intersection properties of balls

  • Cho, Chong-Man
    • Journal of the Korean Mathematical Society
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    • v.31 no.3
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    • pp.467-475
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    • 1994
  • In 1983 Harmand and Lima [5] proved that if X is a Banach space for which K(X), the space of compact linear operators on X, is an M-ideal in L(X), the space of bounded linear operators on X, then it has the metric compact approximation property. A strong converse of the above result holds if X is a closed subspace of either $\elll_p(1 < p < \infty) or c_0 [2,15]$. In 1979 J. Johnson [7] actually proved that if X is a Banach space with the metric compact approximation property, then the annihilator K(X)^\bot$ of K(X) in $L(X)^*$ is the kernel of a norm-one projection in $L(X)^*$, which is the case if K(X) is an M-ideal in L(X).

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One-sided best simultaneous $L_1$-approximation for a compact set

  • Park, Sung-Ho;Rhee, Hyang-Joo
    • Bulletin of the Korean Mathematical Society
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    • v.35 no.1
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    • pp.127-140
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    • 1998
  • In this paper, we discuss the characterizations and uniqueness of a one-sided best simultaneous approximation for a compact subset from a convex subset of a finite-dimensional subspace of a normed linear space $C_1(X)$. The motivation is furnished by the characterizations of the one-sided best simultaneous approximations for a finite subset ${f_1, \ldots, f_\ell}$ for any $\ell \in N$.

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L1-norm Minimization based Sparse Approximation Method of EEG for Epileptic Seizure Detection

  • Shin, Younghak;Seong, Jin-Taek
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.5
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    • pp.521-528
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    • 2019
  • Epilepsy is one of the most prevalent neurological diseases. Electroencephalogram (EEG) signals are widely used for monitoring and diagnosis tool for epileptic seizure. Typically, a huge amount of EEG signals is needed, where they are visually examined by experienced clinicians. In this study, we propose a simple automatic seizure detection framework using intracranial EEG signals. We suggest a sparse approximation based classification (SAC) scheme by solving overdetermined system. L1-norm minimization algorithms are utilized for efficient sparse signal recovery. For evaluation of the proposed scheme, the public EEG dataset obtained by five healthy subjects and five epileptic patients is utilized. The results show that the proposed fast L1-norm minimization based SAC methods achieve the 99.5% classification accuracy which is 1% improved result than the conventional L2 norm based method with negligibly increased execution time (42msec).

SOME ALGORITHMS OF THE BEST SIMULTANEOUS APPROXIMATION

  • Rhee, Hyang J.
    • Journal of the Chungcheong Mathematical Society
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    • v.22 no.2
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    • pp.141-148
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    • 2009
  • We consider various algorithms calculating best onesided simultaneous approximations. We assume that X is a compact subset of $\mathbb{R}^{m}$ satisfying $X=\overline{intX}$, S is an n-dimensional subspace of C(X), and $\mu$ is any 'admissible' measure on X. For any l-tuple $f_1,\;{\cdots},\;f_{\ell}$ in C(X), we present various ideas for best approximation to F from S(F). The problem of best (both one and two-sided) approximation is a linear programming problem.

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SMOOTHING APPROXIMATION TO l1 EXACT PENALTY FUNCTION FOR CONSTRAINED OPTIMIZATION PROBLEMS

  • BINH, NGUYEN THANH
    • Journal of applied mathematics & informatics
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    • v.33 no.3_4
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    • pp.387-399
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    • 2015
  • In this paper, a new smoothing approximation to the l1 exact penalty function for constrained optimization problems (COP) is presented. It is shown that an optimal solution to the smoothing penalty optimization problem is an approximate optimal solution to the original optimization problem. Based on the smoothing penalty function, an algorithm is presented to solve COP, with its convergence under some conditions proved. Numerical examples illustrate that this algorithm is efficient in solving COP.

The study of electron transport coefficients in pure $CO_2$ by 2-term approximation of the Boltzmann equation (2항근사 볼츠만 방정식을 이용한 $CO_2$분자가스의 전자수송계수의 해석)

  • Jeon, Byung-Hoon;Kim, Ji-Yeon;Kim, Song-Gang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.05c
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    • pp.164-167
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    • 2001
  • The electron transport coefficients, the electron drift velocity W, the longitudinal diffusion coefficient $ND_L$ and $D_L/{\mu}$, in pure $CO_2$ were calculated over the wide E/N range from 0.01 to 500 Td at 1 Torr by two-term approximation of the Boltzmann equation for determination of electron collision cross sections set and for quantitative characteristic analysis of $CO_2$ molecular gas. And for propriety of two-term approximation of Boltzmann equation analysis, the calculated results compared with the electron transport coefficients measured by Nakamura.

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AN APPROXIMATION OF THE FOURIER SINE TRANSFORM VIA GRÜSS TYPE INEQUALITIES AND APPLICATIONS FOR ELECTRICAL CIRCUITS

  • DRAGOMIR, S.S.;KALAM, A.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.6 no.1
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    • pp.33-45
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    • 2002
  • An approximation of the Fourier Sine Transform via Gr$\ddot{u}$ss, Chebychev and Lupaş integral inequalities and application for an electrical curcuit containing an inductance L, a condenser of capacity C and a source of electromotive force $E_0P$(t), where P (t) is an $L_2$-integrable function, are given.

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