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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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On the Behavior of Solutions of the System of Rational Difference Equations x_(n+1)=x_(n-1)/y_(n)c_(n-1)-1,y_(n+1)=y_(n-1)/x_(n)y_(n-1)-1,z_(n+1)=x_(n)/y_(n)z_(n-1) 被引量:1
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作者 Abdullah Selcuk Kurbanli Cengiz Cinar Mehmet Emre Erdogan 《Applied Mathematics》 2011年第8期1031-1038,共8页
In this paper, we investigate the solutions of the system of difference equations xn+1=xn-1/ynxn-1-1,yn+1=yn-1/xnyn-1-1,zn+1=xn/ynzn-1 where x0,x-1,y0,y-1,z0,z-1∈R.
关键词 difference equation difference equation Systems Solutions
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On the Periodicity of Solutions of the System of Rational Difference Equations X_(n+1)=X(n-1)+Y_(n)/Y_(n)X_(n-1)-1,Y_(n-1)=Y_(n-1)+X_(n)/X_(n)Y_(n-1)-1
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作者 Abdullah Selcuk Kurbanli Cengiz Cinar Dagistan Simsek 《Applied Mathematics》 2011年第4期410-413,共4页
In this paper, we have investigated the periodicity of the solutions of the system of difference equations , where .
关键词 difference equation difference equation Systems SOLUTIONS
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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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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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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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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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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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ANALYTIC INVARIANT CURVES OF A NONLINEAR SECOND ORDER DIFFERENCE EQUATION 被引量:4
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作者 王五生 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期415-426,共12页
This article studies the existence of analytic invariant curves for a nonlinear second order difference equation which was modeled from macroeconomics of the business cycle. The author not only discusses the case of t... This article studies the existence of analytic invariant curves for a nonlinear second order difference equation which was modeled from macroeconomics of the business cycle. The author not only discusses the case of the eigenvalue off the unit circle S^1 and the case on S^1 with the Diophantine condition but also considers the case of the eigenvalue at a root of the unity, which obviously violates the Diophantine condition. 展开更多
关键词 difference equation invariant curves functional equation ANALYTICITY diophantine condition majorant series
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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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ON ENTIRE SOLUTIONS OF SOME TYPE OF NONLINEAR DIFFERENCE EQUATIONS 被引量:3
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作者 刘慧芳 毛志强 《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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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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ON PROPERTIES OF MEROMORPHIC SOLUTIONS FOR COMPLEX DIFFERENCE EQUATION OF MALMQUIST TYPE 被引量:2
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作者 黄志波 陈宗煊 李倩 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1141-1152,共12页
In this paper, we present the properties on zeros, fixed points, poles, Borel exceptional value of finite order transcendental meromorphic solutions of complex difference equation of Malmquist typewhere n(∈ N) 〉 2... In this paper, we present the properties on zeros, fixed points, poles, Borel exceptional value of finite order transcendental meromorphic solutions of complex difference equation of Malmquist typewhere n(∈ N) 〉 2, P(f(z)) and Q(f(z)) are relatively prime polynomials in f(z) with rational coefficients a8 (s = 0, 1,…,p) and bt (t = 0, 1,… ,q) such that aoapbq 7≠ O, and also consider the existence and the forms on rational solutions of this type of difference equations. Some examples are also listed to show that the assumptions of theorems, in certain senses, are the best possible. 展开更多
关键词 ZEROS POLES FIXED-POINTS Borel exceptional value difference equation
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GLOBAL ATTRACTIVITY IN A CLASS OF HIGHER-ORDER NONLINEAR DIFFERENCE EQUATION 被引量:2
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作者 李万同 张艳红 苏有慧 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期59-66,共8页
In this paper the global attractivity of the nonlinear difference equationis investigated, where a,b, A ∈ (0,∞), k is an positive integer and the initial conditions x- k, …, x-1 and x0 are arbitrary positive number... In this paper the global attractivity of the nonlinear difference equationis investigated, where a,b, A ∈ (0,∞), k is an positive integer and the initial conditions x- k, …, x-1 and x0 are arbitrary positive numbers. It is shown that the unique positive equilibrium of the equation is global attractive. As a corollary, the result gives a positive confirmation on the conjecture presented by Kocic and Ladas [1,p154]. 展开更多
关键词 difference equation global attractivity STABILITY equilibrium.
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GLOBAL ASYMPTOTIC STABILITY FOR A NONLINEAR DELAY DIFFERENCE EQUATION 被引量:6
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作者 LiXianyi ZhuDeming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期183-188,共6页
In this paper,a sufficient condition for the global asymptotic stability of the solutions of the following nonlinear delay difference equation is obtained, xn+ 1=xn+xn- 1xn- 2 +a xnxn- 1+xn- 2 +a, n =0 ,1 ,..., ... In this paper,a sufficient condition for the global asymptotic stability of the solutions of the following nonlinear delay difference equation is obtained, xn+ 1=xn+xn- 1xn- 2 +a xnxn- 1+xn- 2 +a, n =0 ,1 ,..., where a∈ [0 ,∞ ) and the initial values x- 2 ,x- 1,x0 ∈ (0 ,∞ ) .As a special case,a conjecture by Ladas is confirmed. 展开更多
关键词 nonlinear delay difference equation global asymptotic stability semicycle
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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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On global behavior of the system of rational difference equations x_(n+1)=p+y_(n-k)/x_n,y_(n+1)=q+x_(n-k)/y_n 被引量:1
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作者 Xia An1,Tai-xiang Sun2,Yan-fang Zhang11. Department of Basic Courses,Institute of Disaster Prevention Science and Technology,Beijing 065201 2. Department of Mathematics,Guangxi University,Nanning 530004,China. 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第3期189-191,共3页
In this paper,we investigate the boundedness character,the global attractivity and the periodic nature of the system of rational difference equations:x=p+y/x,y=q+x/y,n=0,1,2…,where p>0,q>0,k∈{1,2,…} and the i... In this paper,we investigate the boundedness character,the global attractivity and the periodic nature of the system of rational difference equations:x=p+y/x,y=q+x/y,n=0,1,2…,where p>0,q>0,k∈{1,2,…} and the initial values xi,yi∈(0,∞),i=-k,-k+1,…,0. Some new results are obtained. 展开更多
关键词 difference equation global behavior equilibrium solution boundedness
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ON THE LIMITABILITY OF SOLUTIONS OF SOME DIFFERENCE EQUATIONS 被引量:1
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作者 L.Rempulska B.Szmanda 《Acta Mathematica Scientia》 SCIE CSCD 1997年第1期64-68,共5页
We investigate limitability by the Cesaio (C, 1) and the Abel (A) methods of solutions of some third and fourth order difference equations. Also some results contained in [2],[3] are improved.
关键词 difference equation (C 1)-limitability (A)-limitability
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