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Global smoothness preservation and the variation-diminishing property [PDF]
Journal of Inequalities and Applications, 1999 In the center of our paper are two counterexamples showing the independence of the concepts of global smoothness preservation and variation diminution for sequences of approximation operators.
Gavrea Ioan +4 more
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Global smoothness preservation by bivariate interpolation operators [PDF]
Analysis in Theory and Applications, 2003 The authors extend some interesting results proved earlier by themselves in the univariate case to the bivariate one. They also remark that the results can easily be extended for \(m\) \((> 2)\) variables, too. More precisely they prove that the bivariate interpolation polynomials of Hermite-Fejér based on the Chebyshev nodes of the first kind, those ...
Sorin Gal, J Szabados
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Global smoothness preservation and simultaneous approximation for multivariate general singular integral operators [PDF]
Applied Mathematics Letters, 2011 The author continues with his study of multivariate smooth general singular integral operators over \(\mathbb R^N\), \(N\geq 1\), regarding their simultaneous global smoothness preservation property with respect to the \(L_p\) norm, \(1\leq p\leq \infty \), by involving multivariate higher order moduli of smoothness. Also, he studies their multivariate
George Anastassiou
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Global smoothness preservation by multivariate singular integrals [PDF]
Bulletin of the Australian Mathematical Society, 2000 By using various kinds of moduli of smoothness, it is established that the multivariate variants of the well-known singular integrals of Picard, Poisson-Cauchy, Gauss-Weierstrass and their Jackson-type generalisations satisfy the “global smoothness preservation” property. The results are extensions of those proved by the authors for the univariate case.
Anastassiou, George A., Gal, Sorin G.
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Global smoothness preservation with second order modulus of smoothness
Mathematica Slovaca, 2013 Abstract We establish the global smoothness preservation of a function f by the sequence of linear positive operators. Our estimate is in terms of the second order Ditzian-Totik modulus of smoothness. Application is given to the Bernstein operator.
Gancho Tachev
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On global smoothness preservation in complex approximation [PDF]
Annales Polonici Mathematici, 2002 For a function \(f:\mathbb R^m\to\mathbb R\), set \(\Delta_h^rf(x)=\sum_{i=0}^r(-1)^{r-i}\binom{r}{i} f(x+rh)\), and define the \(r\)th \(L^s\)-modulus of smoothness over \(\mathbb R^m\) by \[ \omega_r(f;\delta)_s: =\sup\{\|\Delta_h^rf(\cdot)\|_{L^s(\mathbb R^m)}; |h|\leq\delta\}, \] where \(r\in\mathbb N\), \(x,h,\delta\in\mathbb R^m\), \(\delta>0\), \
George Anastassiou, Sorin Gal
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Sensors, 2021 Low-contrast or uneven illumination in real-world images will cause a loss of details and increase the difficulty of pattern recognition. An automatic image illumination perception and adaptive correction algorithm, termed as GLAGC, is proposed in this ...
Wenyong Yu +4 more
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Complete Approximations by Multivariate Generalized Gauss-Weierstrass Singular Integrals
Moroccan Journal of Pure and Applied Analysis, 2021 This research and survey article deals exclusively with the study of the approximation of generalized multivariate Gauss-Weierstrass singular integrals to the identity-unit operator.
Anastassiou George A.
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IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021 This article presents a novel global gradient sparse and nonlocal low-rank tensor decomposition model with a hyper-Laplacian prior for hyperspectral image (HSI) superresolution to produce a high-resolution HSI (HR-HSI) by fusing a low-resolution HSI (LR ...
Yidong Peng +3 more
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Low-Light Enhancement Model in Natural Scenes Based on Generative Adversarial Network [PDF]
Jisuanji gongchengIn the most current low-light image enhancement models, both illumination enhancement and original image feature preservation are difficult to achieve and hard to adapt to a variety of different low-light conditions in natural scenes.To address these ...
Ruijun YANG, Jinjing QIN, Yan CHENG
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