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Fuzzy Difference Equations in Diagnoses of Glaucoma from Retinal Images Using Deep Learning
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作者 D.Dorathy Prema Kavitha L.Francis Raj +3 位作者 Sandeep Kautish Abdulaziz S.Almazyad Karam M.Sallam Ali Wagdy Mohamed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期801-816,共16页
The intuitive fuzzy set has found important application in decision-making and machine learning.To enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye ... The intuitive fuzzy set has found important application in decision-making and machine learning.To enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye detection using fuzzy difference equations in the domain where the retinal images converge.Retinal image detections are categorized as normal eye recognition,suspected glaucomatous eye recognition,and glaucomatous eye recognition.Fuzzy degrees associated with weighted values are calculated to determine the level of concentration between the fuzzy partition and the retinal images.The proposed model was used to diagnose glaucoma using retinal images and involved utilizing the Convolutional Neural Network(CNN)and deep learning to identify the fuzzy weighted regularization between images.This methodology was used to clarify the input images and make them adequate for the process of glaucoma detection.The objective of this study was to propose a novel approach to the early diagnosis of glaucoma using the Fuzzy Expert System(FES)and Fuzzy differential equation(FDE).The intensities of the different regions in the images and their respective peak levels were determined.Once the peak regions were identified,the recurrence relationships among those peaks were then measured.Image partitioning was done due to varying degrees of similar and dissimilar concentrations in the image.Similar and dissimilar concentration levels and spatial frequency generated a threshold image from the combined fuzzy matrix and FDE.This distinguished between a normal and abnormal eye condition,thus detecting patients with glaucomatous eyes. 展开更多
关键词 Convolutional Neural Network(CNN) glaucomatous eyes fuzzy difference equation intuitive fuzzy sets image segmentation retinal images
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High-Order Spatial FDTD Solver of Maxwell’s Equations for Terahertz Radiation Production
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作者 Abdelrahman Mahdy 《Journal of Applied Mathematics and Physics》 2024年第4期1028-1042,共15页
We applied a spatial high-order finite-difference-time-domain (HO-FDTD) scheme to solve 2D Maxwell’s equations in order to develop a fluid model employed to study the production of terahertz radiation by the filament... We applied a spatial high-order finite-difference-time-domain (HO-FDTD) scheme to solve 2D Maxwell’s equations in order to develop a fluid model employed to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma. We examined the performance of the applied scheme, in this context, we implemented the developed model to study selected phenomena in terahertz radiation production, such as the excitation energy and conversion efficiency of the produced THz radiation, in addition to the influence of the pulse chirping on properties of the produced radiation. The obtained numerical results have clarified that the applied HO-FDTD scheme is precisely accurate to solve Maxwell’s equations and sufficiently valid to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma. 展开更多
关键词 The Finite-difference-Time-Domain Terahertz Radiation Production Filamentation of Femtosecond Laser Maxwell’s equations Solution
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The Solutions and the Dynamic Behavior of the Rational Difference Equations
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作者 Nisreen A. Bukhary Elsayed M. Elsayed 《Journal of Applied Mathematics and Physics》 2023年第2期525-540,共16页
The main purpose of this paper is to study the dynamic behavior of the rational difference equation of the fourth order Where α, β and γ are positive constants and the initial conditions y<sub>-3</sub>,... The main purpose of this paper is to study the dynamic behavior of the rational difference equation of the fourth order Where α, β and γ are positive constants and the initial conditions y<sub>-3</sub>, y<sub>-2</sub>, y<sub>-1</sub>, y<sub>0</sub> are arbitrary positive real numbers. Also, we obtain the solution of some special cases of this equation and investigate the existence of a periodic solutions of these equations. Finally, some numerical examples will be given to explicate our results. . 展开更多
关键词 difference Equation Local Stability Global Attractor BOUNDEDNESS PERIODIC
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Global Attractivity of a Kind of Delay Difference Equations
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作者 李先义 朱德明 金银来 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期9-18,共10页
Several new sufficient conditions are given for the global attractivity of solutions of a kind of delay difference equations. They either include or improve some known results and put the study of Ladas' conjectur... Several new sufficient conditions are given for the global attractivity of solutions of a kind of delay difference equations. They either include or improve some known results and put the study of Ladas' conjecture forward. 展开更多
关键词 delay difference equation global attractivity positive semicycle negative semicycle periodic point of prime period two
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HIGH RESOLUTION POSITIVITY-PRESERVING DIFFERENCE SCHEMES FOR TWO DIMENSIONAL EULER EQUATIONS
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作者 赵宁 张虎 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期163-168,共6页
A class of high resolution positivity preserving Boltzmann type difference schemes for one and two dimensional Euler equations is studied. First, the relation between Boltzmann and Euler equations is analyzed. By usi... A class of high resolution positivity preserving Boltzmann type difference schemes for one and two dimensional Euler equations is studied. First, the relation between Boltzmann and Euler equations is analyzed. By using a kind of special interpolation, the high resolution Boltzmann type difference scheme is constructed. Finally, numerical tests show that the schemes are effective and useful. 展开更多
关键词 Euler equation Boltzmann equation finite difference scheme positivity preserving
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Asymptotic Behavior and Nonexistence of Positive Solutions of Delay Difference Equations *L
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作者 彭名书 徐千里 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期25-30,共6页
Aim To obtain new criteria for asymptotic behavior and nonexistence of positive solutions of nonlinear neutral delay difference equations. Methods By means of Hlder inequality and a method of direct analysis, some i... Aim To obtain new criteria for asymptotic behavior and nonexistence of positive solutions of nonlinear neutral delay difference equations. Methods By means of Hlder inequality and a method of direct analysis, some interesting Lemmas were offered. Results and Conclusion New criteria for asymptotic behavior and nonexistence of positive solutions of nonlinear neutral delay difference equations are established, which extend and improve the results obtained in the literature. Some interesting examples illustrating the importance of our results are also included. 展开更多
关键词 OSCILLATION asymptotic behavior positive solution neutral delay difference equation NONLINEARITY
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New exact solutions to some difference differential equations 被引量:15
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作者 王振 张鸿庆 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2210-2215,共6页
In this paper, we use our method to solve the extended Lotka-Volterra equation and discrete KdV equation. With the help of Maple, we obtain a number of exact solutions to the two equations including soliton solutions ... In this paper, we use our method to solve the extended Lotka-Volterra equation and discrete KdV equation. With the help of Maple, we obtain a number of exact solutions to the two equations including soliton solutions presented by hyperbolic functions of sinh and cosh, periodic solutions presented by trigonometric functions of sin and cos, and rational solutions. This method can be used to solve some other nonlinear difference-differential equations. 展开更多
关键词 difference differential equation soliton solutions Lotka-Volterra equation discrete KdV equation
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THE GROWTH ORDER OF SOLUTIONS OF SYSTEMS OF COMPLEX DIFFERENCE EQUATIONS 被引量:17
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作者 高凌云 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期814-820,共7页
Using Nevanlinna theory of the value distribution of meromorphic functions and Wiman-Valiron theory of entire functions, we investigate the problem of growth order of solutions of a type of systems of difference equat... Using Nevanlinna theory of the value distribution of meromorphic functions and Wiman-Valiron theory of entire functions, we investigate the problem of growth order of solutions of a type of systems of difference equations, and extend some results of the growth order of solutions of systems of differential equations to systems of difference equations. 展开更多
关键词 Growth order difference equations entire function
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MEROMORPHIC SOLUTIONS OF A TYPE OF SYSTEM OF COMPLEX DIFFERENTIAL-DIFFERENCE EQUATIONS 被引量:5
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作者 李海绸 高凌云 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期195-206,共12页
Applying Nevanlinna theory of the value distribution of meromorphic functions, we mainly study the growth and some other properties of meromorphic solutions of the type of system of complex differential and difference... Applying Nevanlinna theory of the value distribution of meromorphic functions, we mainly study the growth and some other properties of meromorphic solutions of the type of system of complex differential and difference equations of the following form {j=1∑nαj(z)f1(λj1)(z+cj)=R2(z,f2(z)),j=1∑nβj(z)f2(λj2)(z+cj)=R1(z,f1(z)). where λij (j = 1, 2,…, n; i = 1, 2) are finite non-negative integers, and cj (j = 1, 2,… , n) are distinct, nonzero complex numbers, αj(z), βj(z) (j = 1,2,… ,n) are small functions relative to fi(z) (i =1, 2) respectively, Ri(z, f(z)) (i = 1, 2) are rational in fi(z) (i =1, 2) with coefficients which are small functions of fi(z) (i = 1, 2) respectively. 展开更多
关键词 growth order system of equations complex differential equations difference equations Nevanlinna theory value distribution
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KAMENEV-TYPE OSCILLATION CRITERIA FOR DELAY DIFFERENCE EQUATIONS 被引量:6
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作者 程金发 《Acta Mathematica Scientia》 SCIE CSCD 2007年第3期574-580,共7页
Some oscillation criteria are established by Raccati transformation techniques for the following second-order nonlinear neutral difference equation △(pn(△(Xn + CnXn-τ))^γ) + qnX^Bn-σ = 0, n :0, 1, 2...wh... Some oscillation criteria are established by Raccati transformation techniques for the following second-order nonlinear neutral difference equation △(pn(△(Xn + CnXn-τ))^γ) + qnX^Bn-σ = 0, n :0, 1, 2...which extend and include several oscillation criteria in [11], and also correct a theorem and its proof in [10]. 展开更多
关键词 OSCILLATION SUPERLINEAR SUBLINEAR difference equations
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ZEROS OF ENTIRE SOLUTIONS TO COMPLEX LINEAR DIFFERENCE EQUATIONS 被引量:7
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作者 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1141-1148,共8页
In this article, we study the complex oscillation problems of entire solutions to homogeneous and nonhomogeneous linear difference equations, and obtain some relations of the exponent of convergence of zeros and the o... In this article, we study the complex oscillation problems of entire solutions to homogeneous and nonhomogeneous linear difference equations, and obtain some relations of the exponent of convergence of zeros and the order of growth of entire solutions to complex linear difference equations. 展开更多
关键词 Linear difference equation complex oscillation ZERO order of growth
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ON DIFFERENCE EQUATIONS RELATING TO GAMMA FUNCTION 被引量:8
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作者 陈宗煊 黄志波 张然然 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1281-1294,共14页
We consider the existence, the growth, poles, zeros, fixed points and the Borel exceptional value of solutions for the following difference equations relating to Gamma function y(z + 1) -y(z) = R(z) and y(z ... We consider the existence, the growth, poles, zeros, fixed points and the Borel exceptional value of solutions for the following difference equations relating to Gamma function y(z + 1) -y(z) = R(z) and y(z + 1) = P (z)y(z). 展开更多
关键词 difference equation meromorphic function Borel exceptional value
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An Algebraic Method for Constructing Exact Solutions to Difference-Differential Equations 被引量:4
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作者 WANG Zhen ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期211-218,共8页
In this paper, we present a method to solve difference differential equation(s). As an example, we apply this method to discrete KdV equation and Ablowitz-Ladik lattice equation. As a result, many exact solutions ar... In this paper, we present a method to solve difference differential equation(s). As an example, we apply this method to discrete KdV equation and Ablowitz-Ladik lattice equation. As a result, many exact solutions are obtained with the help of Maple including soliton solutions presented by hyperbolic functions sinh and cosh, periodic solutions presented by sin and cos and rational solutions. This method can also be used to other nonlinear difference-differential equation(s). 展开更多
关键词 difference differential equation soliton solutions exact solutions discrete KdV equation Ablowitz-Ladik lattice equations
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ON MEROMORPHIC SOLUTIONS OF RICCATI AND LINEAR DIFFERENCE EQUATIONS 被引量:4
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作者 张然然 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1243-1254,共12页
In this paper, meromorphic solutions of Riccati and linear difference equations are investigated. The growth and Borel exceptional values of these solutions are discussed, and the growth, zeros and poles of difference... In this paper, meromorphic solutions of Riccati and linear difference equations are investigated. The growth and Borel exceptional values of these solutions are discussed, and the growth, zeros and poles of differences of these solutions are also investigated. Furthermore, several examples are given showing that our results are best possible in certain senses. 展开更多
关键词 complex difference equation growth order Borel exceptional value
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SOME DISCRETE NONLINEAR INEQUALITIES AND APPLICATIONS TO DIFFERENCE EQUATIONS 被引量:3
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作者 Cheung Wing-Sum Ma Qing-Hua Josip Pecaric 《Acta Mathematica Scientia》 SCIE CSCD 2008年第2期417-430,共14页
In this article, the authors establish some new nonlinear difference inequalities in two independent variables, which generalize some existing results and can be used as handy tools in the study of qualitative as well... In this article, the authors establish some new nonlinear difference inequalities in two independent variables, which generalize some existing results and can be used as handy tools in the study of qualitative as well as quantitative properties of solutions of certain classes of difference equations. 展开更多
关键词 Discrete Gronwll-Bellman-Ou-Iang type inequalities a Priori bound difference equation boundary value problems
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Existence of asymptotically almost periodic solutions and stability properties for functional difference equations 被引量:4
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作者 吴中华 《Journal of Chongqing University》 CAS 2012年第2期97-102,共6页
For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain li... For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain limiting equation. 展开更多
关键词 functional difference equations asymptotically almost periodic solutions total stability properties
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Nonhomogeneous(H,Q)-Process:The Backward and Forward Equations
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作者 陈柳鑫 李俊平 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期180-183,共4页
As for the backward and forward equation of nonhomogeneous(H, Q) -processes,we proof them in a new way. On the base of that, this paper gives the direct computational formalfor one dimensional distribution of the nonh... As for the backward and forward equation of nonhomogeneous(H, Q) -processes,we proof them in a new way. On the base of that, this paper gives the direct computational formalfor one dimensional distribution of the nonhomogeneous(H, Q) -process. 展开更多
关键词 nonhomogeneous(H Q)-process backward and forward equations one-dimensional distribution
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Numerical simulation of standing wave with 3D predictor-corrector finite difference method for potential flow equations 被引量:3
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作者 罗志强 陈志敏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第8期931-944,共14页
A three-dimensional (3D) predictor-corrector finite difference method for standing wave is developed. It is applied to solve the 3D nonlinear potential flow equa- tions with a free surface. The 3D irregular tank is ... A three-dimensional (3D) predictor-corrector finite difference method for standing wave is developed. It is applied to solve the 3D nonlinear potential flow equa- tions with a free surface. The 3D irregular tank is mapped onto a fixed cubic tank through the proper coordinate transform schemes. The cubic tank is distributed by the staggered meshgrid, and the staggered meshgrid is used to denote the variables of the flow field. The predictor-corrector finite difference method is given to develop the difference equa- tions of the dynamic boundary equation and kinematic boundary equation. Experimental results show that, using the finite difference method of the predictor-corrector scheme, the numerical solutions agree well with the published results. The wave profiles of the standing wave with different amplitudes and wave lengths are studied. The numerical solutions are also analyzed and presented graphically. 展开更多
关键词 three-dimensional (3D) nonlinear potential flow equation predictor-corrector finite difference method staggered grid nested iterative method 3D sloshing
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ON ENTIRE SOLUTIONS OF SOME TYPE OF NONLINEAR DIFFERENCE EQUATIONS 被引量:2
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作者 Huifang LIU Zhiqiang MAO 《Acta Mathematica Scientia》 SCIE CSCD 2018年第3期819-828,共10页
In this article, the existence of finite order entire solutions of nonlinear difference equations fn+ Pd(z, f) = p1 eα1 z+ p2 eα2 z are studied, where n ≥ 2 is an integer, Pd(z, f) is a difference polynomial ... In this article, the existence of finite order entire solutions of nonlinear difference equations fn+ Pd(z, f) = p1 eα1 z+ p2 eα2 z are studied, where n ≥ 2 is an integer, Pd(z, f) is a difference polynomial in f of degree d(≤ n-2), p1, p2 are small meromorphic functions of ez, and α1, α2 are nonzero constants. Some necessary conditions are given to guarantee that the above equation has an entire solution of finite order. As its applications, we also find some type of nonlinear difference equations having no finite order entire solutions. 展开更多
关键词 Nevanlinna theory difference polynomial difference equation entire solution
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GLOBAL ATTRACTIVITY OF NEUTRAL DIFFERENCE EQUATIONS WITH POSITIVE AND NEGATIVE COEFFICIENTS 被引量:2
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作者 Li Xiaoping Jiang Jianchu Gao PingDept. of Math., Loudi Teacher’s College, Loudi 417000,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第3期258-266,共9页
A neutral difference equation with positive and negative coefficientsΔ(x n-c nx n-k )+p nx n-l -q nx n-r =0, n=0,1,2,...,is considered and a sufficient condition for the global attractivity of the ze... A neutral difference equation with positive and negative coefficientsΔ(x n-c nx n-k )+p nx n-l -q nx n-r =0, n=0,1,2,...,is considered and a sufficient condition for the global attractivity of the zero solution of this equation is obtained, which improves and extends the all known results in the literature. 展开更多
关键词 global attractivity neutral difference equations positive and negative coefficients.
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