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Nonlinear Adaptive Wavelet Transform for Lossless Image Compression 被引量:2
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作者 ZHANG Dong YANG Yan QIN Qianqing 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期267-270,共4页
The paper presents a class of nonlinear adaptive wavelet transforms for lossless image compression. In update step of the lifting the different operators are chosen by the local gradient of original image. A nonlinear... The paper presents a class of nonlinear adaptive wavelet transforms for lossless image compression. In update step of the lifting the different operators are chosen by the local gradient of original image. A nonlinear morphological predictor follows the update adaptive lifting to result in fewer large wavelet coefficients near edges for reducing coding. The nonlinear adaptive wavelet transforms can also allow perfect reconstruction without any overhead cost. Experiment results are given to show lower entropy of the adaptive transformed images than those of the non-adaptive case and great applicable potentiality in lossless image compresslon. 展开更多
关键词 adaptive wavelets lifting scheme nonlinear operator morphological predictor image compression
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REGULARIZATION METHODS FOR NONLINEAR ILL-POSED PROBLEMS WITH ACCRETIVE OPERATORS 被引量:2
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作者 王吉安 李景 刘振海 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期141-150,共10页
This article is devoted to the regularization of nonlinear ill-posed problems with accretive operators in Banach spaces. The data involved are assumed to be known approximately. The authors concentrate their discussio... This article is devoted to the regularization of nonlinear ill-posed problems with accretive operators in Banach spaces. The data involved are assumed to be known approximately. The authors concentrate their discussion on the convergence rates of regular solutions. 展开更多
关键词 REGULARIZATION ill-posed problems nonlinear accretive operator convergence rates
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Furi-Martelli-Vignoli spectrum and Feng spectrum of nonlinear block operator matrices 被引量:1
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作者 董小梅 吴德玉 陈阿拉坦仓 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期130-138,共9页
We investigate the Furi-Martelli-Vignoli spectrum and the Feng spectrum of continuous nonlinear block operator matrices,and mainly describe the relationship between the Furi-Martelli-Vignoli spectrum(compared to the F... We investigate the Furi-Martelli-Vignoli spectrum and the Feng spectrum of continuous nonlinear block operator matrices,and mainly describe the relationship between the Furi-Martelli-Vignoli spectrum(compared to the Feng spectrum)of the whole operator matrix and that of its entries.In addition,the connection between the Furi-Martelli-Vignoli spectrum of the whole operator matrix and that of its Schur complement is presented by means of Schur decomposition. 展开更多
关键词 nonlinear operator SPECTRUM block operator matrix
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THE EXISTENCE AND BLOW-UP OF THE RADIAL SOLUTIONS OF A(k_(1),k_(2))-HESSIAN SYSTEM INVOLVING A NONLINEAR OPERATOR AND GRADIENT
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作者 王国涛 杨泽栋 +1 位作者 徐家发 张丽红 《Acta Mathematica Scientia》 SCIE CSCD 2022年第4期1414-1426,共13页
In this paper,we are concerned with the existence of the positive bounded and blow-up radial solutions of the(k1,k2)-Hessian system■where G is a nonlinear operator,Ki=Ski(λ(D^(2) z_(i)))+ψ_(i)(|x|)|▽_(zi)|^(ki),i=... In this paper,we are concerned with the existence of the positive bounded and blow-up radial solutions of the(k1,k2)-Hessian system■where G is a nonlinear operator,Ki=Ski(λ(D^(2) z_(i)))+ψ_(i)(|x|)|▽_(zi)|^(ki),i=1,2.Under the appropriate conditions on gi and g2,our main results are obtained by using the monotone iterative method and the Arzela-Ascoli theorem.Furthermore,our main results also extend the previous existence results for both the single equation and systems. 展开更多
关键词 (k_(1) k_(2))-Hessian system nonlinear operator BLOW-UP monotone iterative method GRADIENT
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A NOTE ON PROBABILISTIC CONTRACTOR COUPLE AND SOLUTIONS FOR A SYSTEM OF NONLINEAR EQUATIONS IN N A MENGER PN-SPACES
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作者 方锦暄 宋桂安 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第7期841-848,共8页
The concept of (Phi, Delta)-type probabilistic contractor couple was introduced which simplifies and weakens the definition of probabilistic contractor couple given by Zhang Shisheng. The existence and uniqueness of t... The concept of (Phi, Delta)-type probabilistic contractor couple was introduced which simplifies and weakens the definition of probabilistic contractor couple given by Zhang Shisheng. The existence and uniqueness of the solutions for a system of nonlinear operator equations with this kind of propabilistic contractor couple in N. A. Menger PN-spaces were studied. The works improve and extend the corresponding results by M. Altman, A. C. Lee, W. J. Padgett et al. 展开更多
关键词 N. A. Menger PN-space (Phi Delta)-probabilistic contractor couple selective operator nonlinear operator equations
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A RANK THEOREM FOR NONLINEAR SEMI-FREDHOLM OPERATORS BETWEEN TWO BANACH MANIFOLDS
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作者 史平 马吉溥 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期107-114,共8页
In this article thc concept of local conjugation of a C^1 mapping between two Banach manifolds is introduced. Thcn a rank theorem for nonlinear scmi-Fredholm operators between two Banach manifolds and a finite rank th... In this article thc concept of local conjugation of a C^1 mapping between two Banach manifolds is introduced. Thcn a rank theorem for nonlinear scmi-Fredholm operators between two Banach manifolds and a finite rank theorem are established in global analysis. 展开更多
关键词 Banach manifold nonlinear semi-Fredholm operators local conjugation rank theorem
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An Efficient Maple Program for Calculating Adomian Polynomials
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作者 Mariam Al-Mazmumy 《American Journal of Computational Mathematics》 2023年第4期512-523,共12页
The immense quest for proficient numerical schemes for the solution of mathematical models featuring nonlinear differential equations led to the realization of the Adomian decomposition method (ADM) in the 80<sup&g... The immense quest for proficient numerical schemes for the solution of mathematical models featuring nonlinear differential equations led to the realization of the Adomian decomposition method (ADM) in the 80<sup>th</sup>. Undoubtedly, the solution of nonlinear differential equations using ADM is presided over by the acquisition of Adomian polynomials, which are not always easy to find. Thus, the present study proposes easy-to-implement Maple programs for the computation of Adomian polynomials. In fact, the proposed algorithms performed remarkably on several test functions, consisting of one- and multi-variable nonlinearities. Moreover, the introduced programs are advantageous in terms of simplicity;coupled with the requirement of less computational time in comparison with what is known in the literature. 展开更多
关键词 nonlinear Operators Adomian Polynomials Adomian Decomposition Method Multi-Variable nonlinearities Maple Package
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INVARIANTS-PRESERVING DU FORT-FRANKEL SCHEMES AND THEIR ANALYSES FOR NONLINEAR SCHRÖDINGER EQUATIONS WITH WAVE OPERATOR
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作者 Dingwen Deng Zhijun Li 《Journal of Computational Mathematics》 SCIE CSCD 2024年第3期814-850,共37页
Du Fort-Frankel finite difference method(FDM)was firstly proposed for linear diffusion equations with periodic boundary conditions by Du Fort and Frankel in 1953.It is an explicit and unconditionally von Neumann stabl... Du Fort-Frankel finite difference method(FDM)was firstly proposed for linear diffusion equations with periodic boundary conditions by Du Fort and Frankel in 1953.It is an explicit and unconditionally von Neumann stable scheme.However,there has been no research work on numerical solutions of nonlinear Schrödinger equations with wave operator by using Du Fort-Frankel-type finite difference methods(FDMs).In this study,a class of invariants-preserving Du Fort-Frankel-type FDMs are firstly proposed for one-dimensional(1D)and two-dimensional(2D)nonlinear Schrödinger equations with wave operator.By using the discrete energy method,it is shown that their solutions possess the discrete energy and mass conservative laws,and conditionally converge to exact solutions with an order of for ofο(T^(2)+h_(x)^(2)+(T/h_(x))^(2))1D problem and an order ofο(T^(2)+h_(x)^(2)+h_(Y)^(2)+(T/h_(X))^(2)+(T/h_(y))^(2))for 2D problem in H1-norm.Here,τdenotes time-step size,while,hx and hy represent spatial meshsizes in x-and y-directions,respectively.Then,by introducing a stabilized term,a type of stabilized invariants-preserving Du Fort-Frankel-type FDMs are devised.They not only preserve the discrete energies and masses,but also own much better stability than original schemes.Finally,numerical results demonstrate the theoretical analyses. 展开更多
关键词 nonlinear Schrodinger equations with wave operator Du Fort-Frankel finite difference methods Discrete energy and mass conservative laws Numerical convergence
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Automatic spikes detection in seismogram
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作者 王海军 靳平 刘贵忠 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第3期348-355,共8页
Data processing for seismic network is very complex and fussy,because a lot of data is recorded in seismicnetwork every day,which make it impossible to process these data all by manual work.Therefore,seismic datashoul... Data processing for seismic network is very complex and fussy,because a lot of data is recorded in seismicnetwork every day,which make it impossible to process these data all by manual work.Therefore,seismic datashould be processed automatically to produce a initial results about events detection and location.Afterwards,these results are reviewed and modified by analyst.In automatic processing data quality checking is important.There are three main problem data that exist in real seismic records,which include:spike,repeated data and 展开更多
关键词 continuous wavelet analysis nonlinear energy operator SPIKES SEISMIC
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A Newton type iterative method for heat-conduction inverse problems
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作者 贺国强 孟泽红 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第4期531-539,共9页
An inverse problem for identification of the coefficient in heat-conduction equation is considered. After reducing the problem to a nonlinear ill-posed operator equation, Newton type iterative methods are considered. ... An inverse problem for identification of the coefficient in heat-conduction equation is considered. After reducing the problem to a nonlinear ill-posed operator equation, Newton type iterative methods are considered. The implicit iterative method is applied to the linearized Newton equation, and the key step in the process is that a new reasonable a posteriori stopping rule for the inner iteration is presented. Numerical experiments for the new method as well as for Tikhonov method and Bakushikskii method are given, and these results show the obvious advantages of the new method over the other ones. 展开更多
关键词 inverse problems nonlinear ill-posed operator equations Newton type method implicit iterative method iteration stopping rule
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The Maximum Dissipative Extension of Schrodinger Operator
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作者 田立新 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第10期973-980,共8页
In the present paper we study the maximum dissipative extension of Schrodingeroperator.introduce the generalized indefinite metvic space and get the representation ofmaximum dissipative extension of Schrodinger operat... In the present paper we study the maximum dissipative extension of Schrodingeroperator.introduce the generalized indefinite metvic space and get the representation ofmaximum dissipative extension of Schrodinger operator in natural boundary space.make preparation for the further study longtime chaotic behaxior of infinite dimensiondynamics system in nonlinear Schrodinger equation. 展开更多
关键词 infinite dimension dynamics system. nonlinear Schfrodingerequation. indefinite metric space. dissipative operator
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Asymptotic Study of a Boundary Value Problem Governed by the Elasticity Operator with Nonlinear Term
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作者 D.Benterki H.Benseridi M.Dilmi 《Advances in Applied Mathematics and Mechanics》 SCIE 2014年第2期191-202,共12页
In this paper,a nonlinear boundary value problem in a three dimensional thin domain with Tresca’s friction law is considered.The small change of variable z=x3/εtransforms the initial problem posed in the domainΩεin... In this paper,a nonlinear boundary value problem in a three dimensional thin domain with Tresca’s friction law is considered.The small change of variable z=x3/εtransforms the initial problem posed in the domainΩεinto a new problem posed on a fixed domainΩindependent of the parameterε.As a main result,we obtain some estimates independent of the small parameter.The passage to the limit onε,permits to prove the results concerning the limit of the weak problem and its uniqueness. 展开更多
关键词 A priori inequalities free boundary problems nonlinear operator Tresca law variational problem.
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A Posteriori Parameter Choice Strategy for Nonlinear Monotone Operator Equations
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作者 Hong-qi Yang, Zong-yi HouDepartment of Scientific Computing & Computer Applications, Zhongshan University, Guangzhou 510275,ChinaDepartment of Mathematics, Pudan University, Shanghai 200433, China 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2002年第2期289-294,共6页
In this paper we present an a posteriori parameter choice strategy for nonlinear ill-posed operator equations involving monotone operators. Under certain conditions, this a posteriori parameter choice strategy guarant... In this paper we present an a posteriori parameter choice strategy for nonlinear ill-posed operator equations involving monotone operators. Under certain conditions, this a posteriori parameter choice strategy guarantees the optimal convergence rate O (δ1/2) for Tikhonov-Browder regularization, where δ denotes the noise level of the data perturbation. 展开更多
关键词 nonlinear operator equation monotone operator convergence rate a posteriori parameter choice
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Image Encryption Application of Chaotic Sequences Incorporating Quantum Keys 被引量:3
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作者 Bin Ge Hai-Bo Luo 《International Journal of Automation and computing》 EI CSCD 2020年第1期123-138,共16页
Abstract This paper proposes an image encryption algorithm LQBPNN(logistic quantum and back propagation neural network)based on chaotic sequences incorporating quantum keys.Firstly,the improved one-dimensional logisti... Abstract This paper proposes an image encryption algorithm LQBPNN(logistic quantum and back propagation neural network)based on chaotic sequences incorporating quantum keys.Firstly,the improved one-dimensional logistic chaotic sequence is used as the basic key sequence.After the quantum key is introduced,the quantum key is incorporated into the chaotic sequence by nonlinear operation.Then the pixel confused process is completed by the neural network.Finally,two sets of different mixed secret key sequences are used to perform two rounds of diffusion encryption on the confusing image.The experimental results show that the randomness and uniformity of the key sequence are effectively enhanced.The algorithm has a secret key space greater than 2182.The adjacent pixel correlation of the encrypted image is close to 0,and the information entropy is close to 8.The ciphertext image can resist several common attacks such as typical attacks,statistical analysis attacks and differential attacks. 展开更多
关键词 Logistic chaotic system quantum key nonlinear operation sequence performance image encryption algorithm
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Convergence of Newton‘’s Method and Uniqueness of the Solution of Equations in Banach SpacesⅡ 被引量:15
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作者 XingHuaWANG ChongLI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第2期405-412,共8页
Some results on convergence of Newton's method in Banach spaces are established under the assumption that the derivative of the operators satisfies the radius or center Lipschitz condition with a weak L average.
关键词 nonlinear operator equation Newton's method Lipschitz condition with L average Convergence ball
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Lipschitz Operators and the Solvability of Non-linear Operator Equations 被引量:2
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作者 HuaiXinCAO ZongBenXU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2004年第3期499-506,共8页
Let U and V be Banach spaces, L and N be non-linear operators from U into V. L is said to be Lipschitz if L 1(L) := sup{∥Lx - Ly∥ · ∥x - y∥-1 : x ≠ y} is finite. In this paper, we give some basic properties ... Let U and V be Banach spaces, L and N be non-linear operators from U into V. L is said to be Lipschitz if L 1(L) := sup{∥Lx - Ly∥ · ∥x - y∥-1 : x ≠ y} is finite. In this paper, we give some basic properties of Lipschitz operators and then discuss the unique solvability, exact solvability, approximate solvability of the operator equations Lx = y and Lx + Nx = y. Under some conditions we prove the equivalence of these solvabilities. We also give an estimation for the relative-errors of the solutions of these two systems and an application of our method to a non-linear control system. 展开更多
关键词 Lipschitz operator nonlinear operator equation SOLVABILITY Control system CONTROLLABILITY
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Novel parametric optimum processing method for airborne radar 被引量:1
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作者 XUJia PENGYingning +3 位作者 WANQun ZHANGLiping LINYan XIAXianggen 《Science in China(Series F)》 2004年第6期706-716,共11页
In radar target detection, an optimum processor needs to automatically adapt its weights to the environment change. Conventionally, the optimum weights are obtained by substantial independently and identically distrib... In radar target detection, an optimum processor needs to automatically adapt its weights to the environment change. Conventionally, the optimum weights are obtained by substantial independently and identically distributed (i.i.d.) interference samplings, which is not always realistic in an inhomogeneous clutter background of airborne radar. The lack of i.i.d. samplings will inevitably lead to performance deterioration for optimum processing. In this paper, a novel parametric adaptive processing method is proposed for airborne radar target detection based on the modified Doppler distributed clutter (DDC) model with contribution of clutter's internal motion. It is different from the conventional methods in that the adaptive weights are determined by two parameters of DDC model, i.e., angular center and spread. A low-complexity nonlinear operators approach is also proposed to estimate these parameters. Simulation and performance analysis are also provided to show that the proposed method can remarkably reduce the dependence of i.i.d. samplings and it is computationally efficient for practical use. 展开更多
关键词 airborne radar adaptive implementation of optimum processing (AIOP) Doppler distributed clutter (DDC) mode independently and identically distributed (i.i.d.) sampling nonlinear energy operator (NLOP).
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Chalcogenide photonic crystal fiber for ultraflat mid-infrared supercontinuum generation 被引量:1
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作者 Sandeep Vyas Takasumi Tanabe +1 位作者 Manish Tiwari Ghanshyam Singh 《Chinese Optics Letters》 SCIE EI CAS CSCD 2016年第12期141-145,共5页
In this Letter, we numerically simulate the generation of a 1–15 μm mid-infrared supercontinuum(SC) from a highly nonlinear Ge_(11.5)As24Se_(64.5)-based photonic crystal fiber(PCF). This ultra-broadband SC i... In this Letter, we numerically simulate the generation of a 1–15 μm mid-infrared supercontinuum(SC) from a highly nonlinear Ge_(11.5)As24Se_(64.5)-based photonic crystal fiber(PCF). This ultra-broadband SC is achieved in a100 mm long PCF pumped using 85 fs laser pulses operated at 3.1 μm and a peak pulse power of 3 k W. The proposed design offers a flat dispersion profile with two zero dispersion wavelengths. This broad and flat dispersion profile of the Ge_(11.5)As24Se_(64.5)PCF, combined with the high nonlinearity(2474 W-1km-1), generates an ultra-broadband SC. 展开更多
关键词 photonic pumped operated broadband nonlinearity numerically soliton silica pumping pitch
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Homogenization of Differential Operators
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作者 Sijue Wu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2002年第1期9-14,共6页
In this note, we present a method of constructing the homogenized operator for a general sequence of differential operators. As an example, we construct the homogenized operator for a sequence of linear parabolic oper... In this note, we present a method of constructing the homogenized operator for a general sequence of differential operators. As an example, we construct the homogenized operator for a sequence of linear parabolic operators. 展开更多
关键词 HOMOGENIZATION Weak limit Weak continuity of nonlinear operators
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