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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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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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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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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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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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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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Nonlinear delay difference equations for housing dynamics assuming heterogeneous backward-looking expectations 被引量:1
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作者 梁以德 徐佳娜 崔詠芯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第6期785-798,共14页
China's first interest rate hike during the last decade, aiming to cool down the seemingly overheated real estate market, had aroused more caution on housing market. This paper aims to analyze the housing price dynam... China's first interest rate hike during the last decade, aiming to cool down the seemingly overheated real estate market, had aroused more caution on housing market. This paper aims to analyze the housing price dynamics after an unanticipated economic shock, which was believed to have similar properties with the backward-looking expecta- tion models. The analysis of the housing price dynamics is based on the cobweb model with a simple user cost affected demand and a stock-flow supply assumption. Several nth- order delay rational difference equations are set up to illustrate the properties of housing dynamics phenomena, such as the equilibrium or oscillations, overshoot or undershoot and convergent or divergent, for a kind of heterogeneous backward-looking expectation models. The results show that demand elasticity is less than supply elasticity is not a necessary condition for the occurrence of oscillation. The housing price dynamics will vary substantially with the heterogeneous backward-looking expectation assumption and some other endogenous factors. 展开更多
关键词 housing price dynamics delay rational difference equations equilibrium and oscillations convergent and divergent overshoot and undershoot
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Positive Solutions of p-Laplacian Functional Difference Equations 被引量:1
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作者 SONG Chang-xiu 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第4期475-481,共7页
In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the p... In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the positive solutions. 展开更多
关键词 p-Laplacian operator functional difference equations positive solution CONE
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EXISTENCE OF POSITIVE SOLUTIONS FOR NEUTRAL DIFFERENCE EQUATIONS WITH POSITIVE AND NEGATIVE COEFFICIENTS 被引量:1
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作者 Luo Zhiguo Shen JianhuaDept. of Math., Hunan Normal Univ., Changsha 410081,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第3期251-257,共7页
In this paper the sufficient conditions for the existence of positive solutions of the neutral difference equations with positive and negative coefficients are established. The results improve some known conclusions i... In this paper the sufficient conditions for the existence of positive solutions of the neutral difference equations with positive and negative coefficients are established. The results improve some known conclusions in the literature. 展开更多
关键词 positive solutions neutral difference equations positive and negative coefficients.
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Traveling Waves for 2-1 Dimension Lattice Difference Equations 被引量:1
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作者 HE Yan-sheng HOU Cheng-min 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期214-223,共10页
A definition is introduced about traveling waves of 2-1 dimension lattice difference equations. Discrete heat equation is introduced and a discussion is given for the existence of traveling waves. The theory of travel... A definition is introduced about traveling waves of 2-1 dimension lattice difference equations. Discrete heat equation is introduced and a discussion is given for the existence of traveling waves. The theory of traveling waves is extended on 2-1 dimension lattice difference equations. As an application, an example is presented to illustrate the main results. 展开更多
关键词 traveling waves lattice difference equations discrete heat equation
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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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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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ON GROWTH OF MEROMORPHIC SOLUTIONS OF NONLINEAR DIFFERENCE EQUATIONS AND TWO CONJECTURES OF C.C. YANG
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作者 张月阳 高宗升 张继龙 《Acta Mathematica Scientia》 SCIE CSCD 2016年第1期195-202,共8页
In this paper, we investigate the growth of the meromorphic solutions of the following nonlinear difference equations F(Z)N+pN-1(F)=0,where n ≥ 2 and small functions as proposed by Yang than 1. Pn-1(f) is a di... In this paper, we investigate the growth of the meromorphic solutions of the following nonlinear difference equations F(Z)N+pN-1(F)=0,where n ≥ 2 and small functions as proposed by Yang than 1. Pn-1(f) is a difference polynomial of degree at most n - 1 in f with coefficients. Moreover, we give two examples to show that one conjecture and Laine [2] does not hold in general if the hyper-order of f(z) is no less 展开更多
关键词 GROWTH meromorphic solutions difference equations CONJECTURES
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HOMOCLINIC SOLUTIONS OF NONLINEAR LAPLACIAN DIFFERENCE EQUATIONS WITHOUT AMBROSETTI-RABINOWITZ CONDITION
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作者 Antonella NASTASI Stepan TERSIAN Calogero VETRO 《Acta Mathematica Scientia》 SCIE CSCD 2021年第3期712-718,共7页
The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mo... The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mountain pass theorem and Palais-Smale compactness condition involving suitable functionals. 展开更多
关键词 difference equations homoclinic solutions non-zero solutions (p q)-Laplacian operator
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THE GROWTH OF DIFFERENCE EQUATIONS AND DIFFERENTIAL EQUATIONS
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作者 Zongxuan CHEN Ranran ZHANG +1 位作者 Shuangting LAN Chuangxin CHEN 《Acta Mathematica Scientia》 SCIE CSCD 2021年第6期1911-1920,共10页
In this paper,we mainly apply a new,asymptotic method to investigate the growth of meromorphic solutions of linear higher order difference equations and differential equations.We delete the condition(1.6)of Theorems E... In this paper,we mainly apply a new,asymptotic method to investigate the growth of meromorphic solutions of linear higher order difference equations and differential equations.We delete the condition(1.6)of Theorems E and F,yet obtain the same results for Theorems E and F.We also weaken the condition(1.4)of Theorems C and D. 展开更多
关键词 asymptotic Method difference equations differential equations
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EXISTENCE OF PERIODIC SOLUTIONS OF SYSTEM OF DIFFERENCE EQUATIONS
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作者 Wei Gengping Shen Jianhua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第3期320-326,共7页
This paper studies the nonautonomous nonlinear system of difference equations △x(n) A(n)x(n) + f(n,x(n)), n∈Z ,(*)where x(n)∈R^N,A(n) = (aij(n))N×N is an N×N matrix, with aij∈C(R,R... This paper studies the nonautonomous nonlinear system of difference equations △x(n) A(n)x(n) + f(n,x(n)), n∈Z ,(*)where x(n)∈R^N,A(n) = (aij(n))N×N is an N×N matrix, with aij∈C(R,R) for i,j = 1,2,3 ,N, and f = (f1,f2,... ,fN)^T ∈C(R×R^N,R^N), satisfying A(t+) = A(t), f(t+ω,z) = f(t, z) for any t∈R, (t, z) ∈R× RN and ∈is a positive integer. Sufficient conditions for the existence of ω-periodic solutions to equations (*) are obtained. 展开更多
关键词 systems of difference equations periodic solutions existence.
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The Growth Order of Solutions of Systems Complex Difference Equations
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作者 LI Xiong-ying 《Chinese Quarterly Journal of Mathematics》 2018年第1期25-31,共7页
In this paper, using Nevanlinna theory of the value distribution of meromorphic functions, the problem of growth order of solutions of a class of system of complex difference equations is investigated, some results ar... In this paper, using Nevanlinna theory of the value distribution of meromorphic functions, the problem of growth order of solutions of a class of system of complex difference equations is investigated, some results are improved and generalized. More precisely,some results of the growth order of solutions of system of differential equations to difference equations are extended. 展开更多
关键词 system of complex difference equations the growth order entire function valuedistribution theory
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On the Asymptotic Behavior of Second Order Quasilinear Difference Equations
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作者 Vadivel Sadhasivam Pon Sundar Annamalai Santhi 《Applied Mathematics》 2016年第14期1612-1631,共21页
In this paper, we investigate the asymptotic behavior of the following quasilinear difference equations (E) where , . We classified the solutions into six types by means of their asymptotic behavior. We establish the ... In this paper, we investigate the asymptotic behavior of the following quasilinear difference equations (E) where , . We classified the solutions into six types by means of their asymptotic behavior. We establish the necessary and/or sufficient conditions for such equations to possess a solution of each of these six types. 展开更多
关键词 Asymptotic Behavior Positive Solutions HOMOGENEOUS Quasilinear difference equations
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New Asymptotical Stability and Uniformly Asymptotical Stability Theorems for Nonautonomous Difference Equations
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作者 Limin Zhang Chaofeng Zhang 《Applied Mathematics》 2016年第10期1023-1031,共9页
New theorems of asymptotical stability and uniformly asymptotical stability for nonautonomous difference equations are given in this paper. The classical Liapunov asymptotical stability theorem of nonautonomous differ... New theorems of asymptotical stability and uniformly asymptotical stability for nonautonomous difference equations are given in this paper. The classical Liapunov asymptotical stability theorem of nonautonomous difference equations relies on the existence of a positive definite Liapunov function that has an indefinitely small upper bound and whose variation along a given nonautonomous difference equations is negative definite. In this paper, we consider the case that the Liapunov function is only positive definite and its variation is semi-negative definite. At these weaker conditions, we put forward a new asymptotical stability theorem of nonautonomous difference equations by adding to extra conditions on the variation. After that, in addition to the hypotheses of our new asymptotical stability theorem, we obtain a new uniformly asymptotical stability theorem of nonautonomous difference equations provided that the Liapunov function has an indefinitely small upper bound. Example is given to verify our results in the last. 展开更多
关键词 Nonautonomous difference equations New Asymptotical Stability Theorem New Uniformly Asymptotical Stability Theorem Liapunovs Direct Method
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ASYMPTOTIC METHOD FOR SINGULAR PERTURBATION PROBLEM OF ORDINARY DIFFERENCE EQUATIONS
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作者 吴启光 苏煜城 孙志忠 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第3期221-230,共10页
This paper is taken up for the following difference equation problem (Pe);where e is a small parameter, c1, c2,constants and functions of k and e . Firstly, the case with constant coefficients is considered. Secondly,... This paper is taken up for the following difference equation problem (Pe);where e is a small parameter, c1, c2,constants and functions of k and e . Firstly, the case with constant coefficients is considered. Secondly, a general method based on extended transformation is given to handle (P.) where the coefficients may be variable and uniform asymptotic expansions are obtained. Finally, a numerical example is provided to illustrate the proposed method. 展开更多
关键词 ASYMPTOTIC METHOD FOR SINGULAR PERTURBATION PROBLEM OF ORDINARY difference equations
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