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1.
In this paper, we focus on the restoration of images that have incomplete data in either the image domain or the transformed
domain or in both. The transform used can be any orthonormal or tight frame transforms such as orthonormal wavelets, tight
framelets, the discrete Fourier transform, the Gabor transform, the discrete cosine transform, and the discrete local cosine
transform. We propose an iterative algorithm that can restore the incomplete data in both domains simultaneously. We prove
the convergence of the algorithm and derive the optimal properties of its limit. The algorithm generalizes, unifies, and simplifies
the inpainting algorithm in image domains given in Cai et al. (Appl Comput Harmon Anal 24:131–149, 2008) and the inpainting
algorithms in the transformed domains given in Cai et al. (SIAM J Sci Comput 30(3):1205–1227, 2008), Chan et al. (SIAM J Sci
Comput 24:1408–1432, 2003; Appl Comput Harmon Anal 17:91–115, 2004). Finally, applications of the new algorithm to super-resolution
image reconstruction with different zooms are presented.
R. H. Chan’s research was supported in part by HKRGC Grant 400505 and CUHK DAG 2060257.
L. Shen’s research was supported by the US National Science Foundation under grant DMS-0712827.
Z. Shen’s research was supported in part by Grant R-146-000-060-112 at the National University of Singapore. 相似文献
2.
We introduce the new idea of recurrent functions to provide a new semilocal convergence analysis for Newton-type methods,
under mild differentiability conditions. It turns out that our sufficient convergence conditions are weaker, and the error
bounds are tighter than in earlier studies in some interesting cases (Chen, Ann Inst Stat Math 42:387–401, 1990; Chen, Numer Funct Anal Optim 10:37–48, 1989; Cianciaruso, Numer Funct Anal Optim 24:713–723, 2003; Cianciaruso, Nonlinear Funct Anal Appl 2009; Dennis 1971; Deuflhard 2004; Deuflhard, SIAM J Numer Anal 16:1–10, 1979; Gutiérrez, J Comput Appl Math 79:131–145, 1997; Hernández, J Optim Theory Appl 109:631–648, 2001; Hernández, J Comput Appl Math 115:245–254, 2000; Huang, J Comput Appl Math 47:211–217, 1993; Kantorovich 1982; Miel, Numer Math 33:391–396, 1979; Miel, Math Comput 34:185–202, 1980; Moret, Computing 33:65–73, 1984; Potra, Libertas Mathematica 5:71–84, 1985; Rheinboldt, SIAM J Numer Anal 5:42–63, 1968; Yamamoto, Numer Math 51: 545–557, 1987; Zabrejko, Numer Funct Anal Optim 9:671–684, 1987; Zinc̆ko 1963). Applications and numerical examples, involving a nonlinear integral equation of Chandrasekhar-type, and a differential
equation are also provided in this study. 相似文献
3.
Shi Sheng Zhang 《数学学报(英文版)》2010,26(2):337-344
The purpose of this paper is to study the weak convergence problems of the irnplicity iteration process for Lipschitzian pseudocontraction semigroups in general Banach spaces. The results presented in this paper extend and improve the corresponding results of Zhou [Nonlinear Anal., 68, 2977-2983 (2008)], Chen, et ah [J. Math. Anal. Appl., 314, 701 709 (2006)], Xu and Ori [Numer. Funct. Anal. Optim, 22, 767-773 (2001)] and Osilike [J. Math. Anal. Appl., 294, 73-81 (2004)]. Keywords 相似文献
4.
In Han and Shen (SIAM J. Math. Anal. 38:530–556, 2006), a family of univariate short support Riesz wavelets was constructed from uniform B-splines. A bivariate spline Riesz wavelet
basis from the Loop scheme was derived in Han and Shen (J. Fourier Anal. Appl. 11:615–637, 2005). Motivated by these two papers, we develop in this article a general theory and a construction method to derive small support
Riesz wavelets in low dimensions from refinable functions. In particular, we obtain small support spline Riesz wavelets from
bivariate and trivariate box splines. Small support Riesz wavelets are desirable for developing efficient algorithms in various
applications. For example, the short support Riesz wavelets from Han and Shen (SIAM J. Math. Anal. 38:530–556, 2006) were used in a surface fitting algorithm of Johnson et al. (J. Approx. Theory 159:197–223, 2009), and the Riesz wavelet basis from the Loop scheme was used in a very efficient geometric mesh compression algorithm in Khodakovsky
et al. (Proceedings of SIGGRAPH, 2000). 相似文献
5.
Deckelnick and Dziuk (Math. Comput. 78(266):645–671, 2009) proved a stability bound for a continuous-in-time semidiscrete parametric finite element approximation of the elastic flow
of closed curves in
\mathbbRd, d 3 2{\mathbb{R}^d, d\geq2} . We extend these ideas in considering an alternative finite element approximation of the same flow that retains some of
the features of the formulations in Barrett et al. (J Comput Phys 222(1): 441–462, 2007; SIAM J Sci Comput 31(1):225–253, 2008; IMA J Numer Anal 30(1):4–60, 2010), in particular an equidistribution mesh property. For this new approximation, we obtain also a stability bound for a continuous-in-time
semidiscrete scheme. Apart from the isotropic situation, we also consider the case of an anisotropic elastic energy. In addition
to the evolution of closed curves, we also consider the isotropic and anisotropic elastic flow of a single open curve in the
plane and in higher codimension that satisfies various boundary conditions. 相似文献
6.
In this paper we investigate POD discretizations of abstract linear–quadratic optimal control problems with control constraints.
We apply the discrete technique developed by Hinze (Comput. Optim. Appl. 30:45–61, 2005) and prove error estimates for the corresponding discrete controls, where we combine error estimates for the state and the
adjoint system from Kunisch and Volkwein (Numer. Math. 90:117–148, 2001; SIAM J. Numer. Anal. 40:492–515, 2002). Finally, we present numerical examples that illustrate the theoretical results. 相似文献
7.
The problem of reducing an algebraic Riccati equation XCX − AX − XD + B = 0 to a unilateral quadratic matrix equation (UQME) of the kind PX
2 + QX + R = 0 is analyzed. New transformations are introduced which enable one to prove some theoretical and computational properties.
In particular we show that the structure preserving doubling algorithm (SDA) of Anderson (Int J Control 28(2):295–306, 1978)
is in fact the cyclic reduction algorithm of Hockney (J Assoc Comput Mach 12:95–113, 1965) and Buzbee et al. (SIAM J Numer
Anal 7:627–656, 1970), applied to a suitable UQME. A new algorithm obtained by complementing our transformations with the
shrink-and-shift technique of Ramaswami is presented. The new algorithm is accurate and much faster than SDA when applied
to some examples concerning fluid queue models. 相似文献
8.
Jean-Marie Mirebeau 《Constructive Approximation》2010,32(2):339-383
Given a function f defined on a bounded domain Ω⊂ℝ2 and a number N>0, we study the properties of the triangulation TN\mathcal{T}_{N} that minimizes the distance between f and its interpolation on the associated finite element space, over all triangulations of at most N elements. The error is studied in the norm X=L
p
for 1≤p≤∞, and we consider Lagrange finite elements of arbitrary polynomial degree m−1. We establish sharp asymptotic error estimates as N→+∞ when the optimal anisotropic triangulation is used, recovering the results on piecewise linear interpolation (Babenko
et al. in East J. Approx. 12(1), 71–101, 2006; Babenko, submitted; Chen et al. in Math. Comput. 76, 179–204, 2007) and improving the results on higher degree interpolation (Cao in SIAM J. Numer. Anal. 45(6), 2368–2391, 2007, SIAM J. Sci. Comput. 29, 756–781, 2007, Math. Comput. 77, 265–286, 2008). These estimates involve invariant polynomials applied to the m-th order derivatives of f. In addition, our analysis also provides practical strategies for designing meshes such that the interpolation error satisfies
the optimal estimate up to a fixed multiplicative constant. We partially extend our results to higher dimensions for finite
elements on simplicial partitions of a domain Ω⊂ℝ
d
. 相似文献
9.
On the Block Independence in G-Inverse and Reflexive Inner Inverse of A Partitioned Matrix 总被引:1,自引:0,他引:1
Yong Hui LIU Mu Sheng WEI 《数学学报(英文版)》2007,23(4):723-730
By applying the multiple quotient singular value decomposition QQQQQ-SVD, we study the block independence in g-inverse and reflexive inner inverse of 2× 2 partitioned matrices, and prove a conjecture in [Yiju Wang, SIAM J. Matrix Anal. Appl., 19(2), 407-415(1998)]. 相似文献
10.
In this paper, a priori error estimates for space–time finite element discretizations of optimal control problems governed
by semilinear parabolic PDEs and subject to pointwise control constraints are derived. We extend the approach from Meidner
and Vexler (SIAM Control Optim
47(3):1150–1177, 2008; SIAM Control Optim 47(3):1301–1329, 2008) where linear-quadratic problems have been considered, discretizing the state equation by usual conforming finite elements
in space and a discontinuous Galerkin method in time. Error estimates for controls discretized by piecewise constant functions
in time and cellwise constant functions in space are derived in detail and we explain how error estimate for further discretization
approaches, e.g., cellwise linear discretization in space, the postprocessing approach from Meyer and R?sch (SIAM J Control
Optim 43:970–985, 2004), and the variationally discrete approach from Hinze (J Comput Optim Appl 30:45–63, 2005) can be obtained. In addition, we derive an estimate for a setting with finitely many time-dependent controls. 相似文献
11.
We give a shorter proof of Kanter’s (J. Multivariate Anal. 6, 222–236, 1976) sharp Bessel function bound for concentrations of sums of independent symmetric random vectors. We provide
sharp upper bounds for the sum of modified Bessel functions I0(x) + I1(x), which might be of independent interest. Corollaries improve concentration or smoothness bounds for sums of independent
random variables due to Čekanavičius & Roos (Lith. Math. J. 46, 54–91, 2006); Roos (Bernoulli, 11, 533–557, 2005), Barbour & Xia (ESAIM Probab. Stat. 3, 131–150, 1999), and Le Cam (Asymptotic Methods in Statistical Decision Theory. Springer, Berlin Heidelberg New York, 1986).
相似文献
12.
YoungHoKIM 《数学学报(英文版)》2004,20(1):57-62
In this paper,some new generalizations of inverse type Hilbert-Pachpatte integral inequalities are proved.The results of this paper reduce to those of Pachpatte(1998,J.Math.Anal.Appl.226,166-179)and Zhan and Debnath(2001,J.Math.Anal.Appl.262,411-418). 相似文献
13.
Ioannis K. Argyros 《Numerical Algorithms》2010,54(4):485-501
We provide a semilocal convergence analysis for a certain class of secant-like methods considered also in Argyros (J Math
Anal Appl 298:374–397, 2004, 2007), Potra (Libertas Mathematica 5:71–84, 1985), in order to approximate a locally unique solution of an equation in a Banach space. Using a combination of Lipschitz and
center-Lipschitz conditions for the computation of the upper bounds on the inverses of the linear operators involved, instead
of only Lipschitz conditions (Potra, Libertas Mathematica 5:71–84, 1985), we provide an analysis with the following advantages over the work in Potra (Libertas Mathematica 5:71–84, 1985) which improved the works in Bosarge and Falb (J Optim Theory Appl 4:156–166, 1969, Numer Math 14:264–286, 1970), Dennis (SIAM J Numer Anal 6(3):493–507, 1969, 1971), Kornstaedt (1975), Larsonen (Ann Acad Sci Fenn, A 450:1–10, 1969), Potra (L’Analyse Numérique et la Théorie de l’Approximation 8(2):203–214, 1979, Aplikace Mathematiky 26:111–120, 1981, 1982, Libertas Mathematica 5:71–84, 1985), Potra and Pták (Math Scand 46:236–250, 1980, Numer Func Anal Optim 2(1):107–120, 1980), Schmidt (Period Math Hung 9(3):241–247, 1978), Schmidt and Schwetlick (Computing 3:215–226, 1968), Traub (1964), Wolfe (Numer Math 31:153–174, 1978): larger convergence domain; weaker sufficient convergence conditions, finer error bounds on the distances involved, and
a more precise information on the location of the solution. Numerical examples further validating the results are also provided. 相似文献
14.
In recent years, a rapidly growing literature has focussed on the construction of wavelet systems to analyze functions defined
on the sphere. Our purpose in this paper is to generalize these constructions to situations where sections of line bundles,
rather than ordinary scalar-valued functions, are considered. In particular, we propose needlet-type spin wavelets as an extension of the needlet approach recently introduced by Narcowich et al. in SIAM J. Math. Anal. 38, 574–594 (2006) and J. Funct. Anal. 238, 530–564 (2006) and then considered for more general manifolds by Geller and Mayeli in Math. Z. 262, 895–927 (2009), Math. Z. 263, 235–264 (2009), and Indiana Univ. Math. J. (2009). We discuss localization properties in the real and harmonic domains, and investigate stochastic properties for the analysis
of spin random fields. Our results are strongly motivated by cosmological applications, in particular in connection to the
analysis of Cosmic Microwave Background polarization data. 相似文献
15.
This paper is devoted to the convergence and stability analysis of a class of nonlinear subdivision schemes and associated
multiresolution transforms. As soon as a nonlinear scheme can be written as a specific perturbation of a linear and convergent
subdivision scheme, we show that if some contractivity properties are satisfied, then stability and convergence can be achieved.
This approach is applied to various schemes, which give different new results. More precisely, we study uncentered Lagrange
interpolatory linear schemes, WENO scheme (Liu et al., J Comput Phys 115:200–212, 1994), PPH and Power-P schemes (Amat and Liandrat, Appl Comput Harmon Anal 18(2):198–206, 2005; Serna and Marquina, J Comput Phys 194:632–658, 2004) and a nonlinear scheme using local spherical coordinates (Aspert et al., Comput Aided Geom Des 20:165–187, 2003). Finally, a stability proof is given for the multiresolution transform associated to a nonlinear scheme of Marinov et al.
(2005). 相似文献
16.
Yat-Ming Chan 《Annals of Global Analysis and Geometry》2009,35(1):91-114
In this paper we extend our previous results on resolving conically singular Calabi–Yau 3-folds (Chan, Quart. J. Math. 57:151–181,
2006; Quart. J. Math., to appear) to include the desingularizations of special Lagrangian (SL) 3-folds with conical singularities
that occur at the same points of the ambient Calabi–Yau. The gluing construction of the SL 3-folds is achieved by applying
Joyce’s analytic result (Joyce, Ann. Global. Anal. Geom. 26: 1–58, 2004, Thm. 5.3) on deforming Lagrangian submanifolds to
nearby special Lagrangian submanifolds. Our result will in principle be able to construct more examples of compact SL submanifolds
in compact Calabi–Yau manifolds. Various explicit examples and applications illustrating the result in this paper can be found
in the sequel (Chan, Ann. Global. Anal. Geom., to appear). 相似文献
17.
A refinable spline in ℝ
d
is a compactly supported refinable function whose support can be decomposed into simplices such that the function is a polynomial
on each simplex. The best-known refinable splines in ℝ
d
are the box splines. Refinable splines play a key role in many applications, such as numerical computation, approximation
theory and computer-aided geometric design. Such functions have been classified in one dimension in Dai et al. (Appl. Comput.
Harmon. Anal. 22(3), 374–381, 2007), Lawton et al. (Comput. Math. 3, 137–145, 1995). In higher dimensions Sun (J. Approx. Theory 86, 240–252, 1996) characterized those splines when the dilation matrices are of the form A=mI, where m∈ℤ and I is the identity matrix. For more general dilation matrices the problem becomes more complex. In this paper we give a complete
classification of refinable splines in ℝ
d
for arbitrary dilation matrices A∈M
d
(ℤ). 相似文献
18.
We show that a (non-negative) measure on a circle coarse-grained system of sets can be extended, as a (non-negative) measure,
over the collection of all subsets of the circle. This result contributes to quantum logic probability (de Lucia in Colloq
Math 80(1):147–154, 1999; Gudder in Quantum Probability, Academic Press, San Diego, 1988; Gudder in SIAM Rev 26(1):71–89,
1984; Harding in Int J Theor Phys 43(10):2149–2168, 2004; Navara and Pták in J Pure Appl Algebra 60:105–111, 1989; Pták in
Proc Am Math Soc 126(7):2039–2046, 1998, etc.) and completes the analysis of coarse-grained measures carried on in De Simone
and Pták (Bull Pol Acad Sci Math 54(1):1–11, 2006; Czechoslov Math J 57(132) n.2:737–746, 2007), Gudder and Marchand (Bull
Pol Acad Sci Math 28(11–12):557–564, 1980) and Ovchinnikov (Construct Theory Funct Funct Anal 8:95–98, 1992). 相似文献
19.
In this paper, we address the problem of the existence of superconvergence points of approximate solutions, obtained from
the Generalized Finite Element Method (GFEM), of a Neumann elliptic boundary value problem. GFEM is a Galerkin method that
uses non-polynomial shape functions, and was developed in (Babuška et al. in SIAM J Numer Anal 31, 945–981, 1994; Babuška
et al. in Int J Numer Meth Eng 40, 727–758, 1997; Melenk and Babuška in Comput Methods Appl Mech Eng 139, 289–314, 1996).
In particular, we show that the superconvergence points for the gradient of the approximate solution are the zeros of a system
of non-linear equations; this system does not depend on the solution of the boundary value problem. For approximate solutions
with second derivatives, we have also characterized the superconvergence points of the second derivatives of the approximate
solution as the roots of a system of non-linear equations. We note that smooth generalized finite element approximation is
easy to construct.
I. Babuška’s research was partially supported by NSF Grant # DMS-0341982 and ONR Grant # N00014-99-1-0724.
U. Banerjee’s research was partially supported by NSF Grant # DMS-0341899.
J. E. Osborn’s research was supported by NSF Grant # DMS-0341982. 相似文献
20.
Yat-Ming Chan 《Annals of Global Analysis and Geometry》2009,35(2):157-180
This article is a sequel to Chan (Ann Glob Anal Geom, to appear) on simultaneous desingularizations of Calabi–Yau and special
Lagrangian (SL) 3-folds with conical singularities. In Chan (Ann Glob Anal Geom, to appear) we treated the question of starting
with a conically singular Calabi–Yau 3-fold and an SL 3-fold with conical singularities at the same points and deforming both
together to get a smooth situation. In this article, we survey the major result from Chan (Ann Glob Anal Geom, to appear)
and describe some examples from our earlier articles (Chan Q J Math 57:151–181, 2006, Q J Math, to appear) on Calabi–Yau desingularizations.
We then provide many explicit examples of Asymptotically Conical (AC) SL submanifolds in two specific AC Calabi–Yau manifolds.
Using the result in Chan (Ann Glob Anal Geom, to appear), we construct smooth examples of compact SL 3-folds in compact Calabi–Yau
3-folds by gluing those AC SL 3-folds into some conically singular SL 3-folds at the singular points. 相似文献