• Title/Summary/Keyword: p-norm

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Np-SPACES

  • Kim, Yun-Su
    • Journal of the Korean Mathematical Society
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    • v.48 no.5
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    • pp.1043-1052
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    • 2011
  • We introduce a new norm, called the $N^p$-norm (1 $\leq$ p < ${\infty}$ on the space $N^p$(V,W) where V and W are abstract operator spaces. By proving some fundamental properties of the space $N^p$(V,W), we also discover that if W is complete, then the space $N^p$(V,W) is also a Banach space with respect to this norm for 1 $\leq$ p < ${\infty}$.

Robust inversion of seismic data using ${\ell}^1/{\ell}^2$ norm IRLS method (${\ell}^1/{\ell}^2$ norm IRLS 방법을 사용한 강인한 탄성파자료역산)

  • Ji Jun
    • 한국지구물리탐사학회:학술대회논문집
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    • 2005.05a
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    • pp.227-232
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    • 2005
  • Least squares (${\ell}^2-norm$) solutions of seismic inversion tend to be very sensitive to data points with large errors. The ${\ell}^p-norm$ minimization for $1{\le}p<2$ gives more robust solutions, but usually with higher computational cost. Iteratively reweighted least squares (IRLS) gives efficient approximate solutions of these ${\ell}^p-norm$ problems. I propose a simple way to implement the IRLS method for a hybrid ${\ell}^1/{\ell}^2$ minimization problem that behaves as ${\ell}^2$ fit for small residual and ${\ell}^1$ fit for large residuals. Synthetic and a field-data examples demonstrates the improvement of the hybrid method over least squares when there are outliers in the data.

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A REMARK ON SOME INEQUALITIES FOR THE SCHATTEN p-NORM

  • HEDAYATIAN, K.;BAHMANI, F.
    • Honam Mathematical Journal
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    • v.24 no.1
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    • pp.9-23
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    • 2002
  • For a closed densely defined linear operator T on a Hilbert space H, let ${\prod}$ denote the function which corresponds to T, the orthogonal projection from $H{\oplus}H$ onto the graph of T. We extend some ordinary norm ineqralites comparing ${\parallel}{\Pi}(A)-{\Pi}(B){\parallel}$ and ${\parallel}A-B{\parallel}$ to the Schatten p-norm where A and B are bounded operators on H.

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A Comparative Analysis of the Relevance Weighted Boolean Model and the P-NORM Model: An Improvement on the Boolean Retrieval (적합성 가중치 검색 및 P-NORM 검색에 관한 연구 -불 논리 검색의 개선을 중심으로-)

  • 이효숙
    • Journal of the Korean Society for information Management
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    • v.11 no.1
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    • pp.31-56
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    • 1994
  • To evaluate the retrieval effectiveness of the B03lean Request Conversion Mod4 the Relevance Weighted Boolean Model, and the P-NORM Model, the present study has been done with expenmental tests. It is proven that the Relevance Weighted Bdean Model is more effective in precision and the document output ranks than the other ones. The expenmental results indmte a promisii application of relevance mformation and weigh- schemes.

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Robust Multiuser Detection Based on Least p-Norm State Space Filtering Model

  • Zha, Daifeng
    • Journal of Communications and Networks
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    • v.9 no.2
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    • pp.185-191
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    • 2007
  • Alpha stable distribution is better for modeling impulsive noises than Gaussian distribution in signal processing. This class of process has no closed form of probability density function and finite second order moments. In general, Wiener filter theory is not meaningful in S$\alpha$SG environments because the expectations may be unbounded. We proposed a new adaptive recursive least p-norm Kalman filtering algorithm based on least p-norm of innovation process with infinite variances, and a new robust multiuser detection method based on least p-norm Kalman filtering. The simulation experiments show that the proposed new algorithm is more robust than the conventional Kalman filtering multiuser detection algorithm.

SAR Interferometry Phase Unwrapping 비교 분석: Branch cut, Minimum discontinuity 및 Minimum $L^p$-norm 방법을 중심으로

  • 김상완;이효재;원중선
    • Proceedings of the KSRS Conference
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    • 2000.04a
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    • pp.96-101
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    • 2000
  • SAR(Synthetic Aperture Radar) interferometry 기술은 co-registration, 정밀궤도 계산, phase unwrapping, 지형보정과 같은 기술로 구성되어있다. 구속화된 위상값을 절대 위상값으로 변환하는 과정인 phase unwrapping 기술은 정밀지형고도를 얻는데 있어서 핵심기술이다. 본 연구에서는 JERS-1 SAR 영상으로부터 interferogram을 구하고, 이로부터 추출된 위상정보를 이용하여 branch cut(Goldstein et. al, 1988), minimum discontinuity(Flynn, 1997) 그리고 minimum $L^p$-norm(Ghiglia and Romero, 1996)방법 적용결과에 대한 비교 분석을 실시하였다. Goldstein 알고리즘은 수행속동가 매우 빠르지만 residue를 연결한 branch cut에 의해 분활된 영역 내에서, 서로 다른 적분 경로로 인해 위상이 단절되었다. 영상내의 모든 화소에서 절대 위상을 구한 minimum discontinuity와 minimum $L^p$-norm 알고리즘 수행 결과는 상관관계가 0.995로 매우 유사하였는데, 가중된 불연속선의 합을 최소화하는 minimum discontinuity 알고리즘이 minimum $L^p$-norm에 비해 영상 일부 지역에서 발생하는 위상 오차를 전파시키지 않는다는 장점이 있다. Minimum $L^p$-norm 방법은 다른 두 방법과 달리 위상정보 내에 많은 잡음이 있더라도 적절한 해를 구할 수 있다는 장점이 있다. 각 방법은 대상 자료의 특성에 따라 효율성이 있으나 Flynn의 알고리즘이 지역적 특성과 무관하게 가장 효과적임을 알 수 있었다.

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Norm and Numerical Radius of 2-homogeneous Polynomials on the Real Space lp2, (1 < p > ∞)

  • Kim, Sung-Guen
    • Kyungpook Mathematical Journal
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    • v.48 no.3
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    • pp.387-393
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    • 2008
  • In this note, we present some inequalities for the norm and numerical radius of 2-homogeneous polynomials from the 2-dimensional real space $l_p^2$, (1 < p < $\infty$) to itself in terms of their coefficients. We also give an upper bound for n^{(k)}(l_p^2), (k = 2, 3, $\cdots$).

Heart Rate Variability in Patients Who Visit Dept. of Oriental Medical Opthalmology & Otolaryngology & Dermatology : Those Who Have Self-Recognized Stress (안이비인후피부 환자의 HRV 검사 : 자가 스트레스 인식자를 대상으로)

  • Kim, Yoon-Bum;Nam, Hae-Jeong
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.18 no.3
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    • pp.66-74
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    • 2005
  • Objective: Stress is one of the most important etiological factors in our lives. Human body makes effort to keep his homeostasis from stress by using autonomic nerve system. So we need markers which can evaluate autonomic nerve system easily. HRV represents such markers. Sympathetic and Parasympathetic nerve system are part of autonomic nerve system, related with cur body and diseases in ENT, Dermatology, Ophthalmology are also deeply related with stress, Sympathetic and Parasympathetic nerve system. So we can expect that it can help understanding patients to evaluate autonomic nerve system with HRV Research Methods and Procedures: Forty one patients who have seif-recognized stress in Dept. of Oph & Otolaryngo & Dermatology were selected. SDNN. RMSSD, LF, HF, norm-LF, norm-HF, LF/HF ratio, LnLF, LnHF were checked. Results: Men showed lower SDNN, HF, and LnHF than women(p<0.05). Age over-forty group showed significant lower SDNN, LF, HF, LnLF, LnH(p<0.01), and lower RMSSD(p<0.05) than age under-forty group. There's no big differences for age at norm-LF, norm-HF, and LF/HF ratio. Skin disease group showed higher SDNN, RMSSD, LF, HF, LnLF, LNHF than the others, facial palsy group showed higher norm-HF. LF/HF ratio, and mouth-throat group showed higher norm-LF, but there's no statically significant difference. Comparing skin disease group with the others, the others showed statically significant low SDNN(P<0.01), RMSSD, LF, HF, LnLF and LnHF(P<0.05).

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