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Sensing and Communication Integrated Fast Neighbor Discovery for UAV Networks
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作者 WEI Zhiqing ZHANG Yongji +1 位作者 JI Danna LI Chenfei 《ZTE Communications》 2024年第3期69-82,共14页
In unmanned aerial vehicle(UAV)networks,the high mobility of nodes leads to frequent changes in network topology,which brings challenges to the neighbor discovery(ND)for UAV networks.Integrated sensing and communicati... In unmanned aerial vehicle(UAV)networks,the high mobility of nodes leads to frequent changes in network topology,which brings challenges to the neighbor discovery(ND)for UAV networks.Integrated sensing and communication(ISAC),as an emerging technology in 6G mobile networks,has shown great potential in improving communication performance with the assistance of sensing information.ISAC obtains the prior information about node distribution,reducing the ND time.However,the prior information obtained through ISAC may be imperfect.Hence,an ND algorithm based on reinforcement learning is proposed.The learning automaton(LA)is applied to interact with the environment and continuously adjust the probability of selecting beams to accelerate the convergence speed of ND algorithms.Besides,an efficient ND algorithm in the neighbor maintenance phase is designed,which applies the Kalman filter to predict node movement.Simulation results show that the LA-based ND algorithm reduces the ND time by up to 32%compared with the Scan-Based Algorithm(SBA),which proves the efficiency of the proposed ND algorithms. 展开更多
关键词 unmanned aerial vehicle networks neighbor discovery integrated sensing and communication reinforcement learning Kalman filter
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Existence of Solutions of a Convolution Integral Equation
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作者 Henry Otoo Benjamin Dadzie Mensah Lewis Brew 《Journal of Applied Mathematics and Physics》 2024年第5期1835-1847,共13页
In this study, we prove the of existence of solutions of a convolution Volterra integral equation in the space of the Lebesgue integrable function on the set of positive real numbers and with the standard norm defined... In this study, we prove the of existence of solutions of a convolution Volterra integral equation in the space of the Lebesgue integrable function on the set of positive real numbers and with the standard norm defined on it. An operator P was assigned to the convolution integral operator which was later expressed in terms of the superposition operator and the nonlinear operator. Given a ball B<sub>r</sub> belonging to the space L it was established that the operator P maps the ball into itself. The Hausdorff measure of noncompactness was then applied by first proving that given a set M∈ B r the set is bounded, closed, convex and nondecreasing. Finally, the Darbo fixed point theorem was applied on the measure obtained from the set E belonging to M. From this application, it was observed that the conditions for the Darbo fixed point theorem was satisfied. This indicated the presence of at least a fixed point for the integral equation which thereby implying the existence of solutions for the integral equation. 展开更多
关键词 VOLTERRA integral Equation CONVOLUTION Fixed point EXISTENCE Noncompactness
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A fixed point theorem for a class of β-constrictive operators and its application to the integral equation in L^1(0,∞)
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作者 吴从忻 刘笑颖 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第2期143-146,共4页
Presents the fixed point theorem for a class of β constrictive increasing operators without continuity and discusses the existence of solution of the integral equation with the discontinuous term in L 1(0,∞)... Presents the fixed point theorem for a class of β constrictive increasing operators without continuity and discusses the existence of solution of the integral equation with the discontinuous term in L 1(0,∞) by using this theorem. 展开更多
关键词 CONSTRICTIVE increasing operator fixed point integral equation
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Common Fixed Points for Two Contractive Mappings of Integral Type in Metric Spaces
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作者 Xing Jin Yongjie Piao 《Applied Mathematics》 2015年第6期1009-1016,共8页
In this paper, we obtain unique common fixed point theorems for two mappings satisfying the variable coefficient linear contraction of integral type and the implicit contraction of integral type respectively in metric... In this paper, we obtain unique common fixed point theorems for two mappings satisfying the variable coefficient linear contraction of integral type and the implicit contraction of integral type respectively in metric spaces. 展开更多
关键词 Contractive MAPPING of integral Type COMMON Fixed point METRIC SPACE
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To Theory One Class Linear Model Noclassical Volterra Type Integral Equation with Left Boundary Singular Point
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作者 Nusrat Rajabov 《Applied Mathematics》 2013年第9期1301-1312,共12页
In this work, we investigate one class of Volterra type integral equation, in model case, when kernels have first order fixed singularity and logarithmic singularity. In detail study the case, when n = 3. In depend of... In this work, we investigate one class of Volterra type integral equation, in model case, when kernels have first order fixed singularity and logarithmic singularity. In detail study the case, when n = 3. In depend of the signs parameters solution to this integral equation can contain three arbitrary constants, two arbitrary constants, one constant and may have unique solution. In the case when general solution of integral equation contains arbitrary constants, we stand and investigate different boundary value problems, when conditions are given in singular point. Besides for considered integral equation, the solution found cane represented in generalized power series. Some results obtained in the general model case. 展开更多
关键词 NEOCLASSICAL VOLTERRA Type integral Equation LEFT BOUNDARY SINGULAR point BOUNDARY Value Problems
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ON THE EXISTENCE OF INFINITELY MANY CRITICAL POINTS OF THE EVEN FUNCTIONAL integral from n=Q to (F(x,u,Du))+integral from n=■Q to (G(x,u))
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作者 严树森 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期231-240,共10页
In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o... In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o to u (g(x,t)dt), under the weak structure conditions on F(x, u, q) by the Mountain Pass Lemma. 展开更多
关键词 ON THE EXISTENCE OF INFINITELY MANY CRITICAL pointS OF THE EVEN FUNCTIONAL integral from n=Q to x u Du ON THE EXISTENCE OF INFINITELY MANY CRITICAL pointS OF THE EVEN FUNCTIONAL integral from n Q to x u
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Existence of Positive Solutions for Systems of Second-order Nonlinear Singular Differential Equations with Integral Boundary Conditions on Infinite Interval 被引量:18
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作者 LI Yao-hong 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期55-64,共10页
By using cone theory and the MSnch fixed theorem combined with a monotone iterative technique, we investigate the existence of positive solutions for systems of second- order nonlinear singular differential equations ... By using cone theory and the MSnch fixed theorem combined with a monotone iterative technique, we investigate the existence of positive solutions for systems of second- order nonlinear singular differential equations with integral boundary conditions on infinite interval and establish the existence theorem of positive solutions and iterative sequence for approximating the positive solutions. The results in this paper improve some known results. 展开更多
关键词 boundary value problems positive solutions integral boundary conditions theMSnch fixed point theorem
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EXISTENCE AND UNIQUENESS OF SOLUTIONS FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS WITH NON-SEPARATED TYPE INTEGRAL BOUNDARY CONDITIONS 被引量:6
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作者 Bashir Ahmad Juan J. Nieto Ahmed Alsaedi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2122-2130,共9页
In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results a... In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-Schauder degree theory. Some illustrative examples are also presented. We extend previous results even in the integer case q = 2. 展开更多
关键词 fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem LeraySchauder degree
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FRACTIONAL INTEGRAL INEQUALITIES AND THEIR APPLICATIONS TO FRACTIONAL DIFFERENTIAL EQUATIONS 被引量:2
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作者 Yaghoub JALILIAN 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1317-1330,共14页
In this paper, first we obtain some new fractional integral inequalities. Then using these inequalities and fixed point theorems, we prove the existence of solutions for two different classes of functional fractional ... In this paper, first we obtain some new fractional integral inequalities. Then using these inequalities and fixed point theorems, we prove the existence of solutions for two different classes of functional fractional differential equations. 展开更多
关键词 fractional integral inequality existence of solution Caputo fractional derivative fractional differential equation fixed point
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Second Order Periodic Boundary Value Problems Involving the Distributional Henstock-Kurzweil Integral 被引量:3
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作者 Xueyuan Zhou Guoju Ye 《Advances in Pure Mathematics》 2012年第5期330-336,共7页
We apply the distributional derivative to study the existence of solutions of the second order periodic boundary value problems involving the distributional Henstock-Kurzweil integral. The distributional Henstock-Kurz... We apply the distributional derivative to study the existence of solutions of the second order periodic boundary value problems involving the distributional Henstock-Kurzweil integral. The distributional Henstock-Kurzweil integral is a general intergral, which contains the Lebesgue and Henstock-Kurzweil integrals. And the distributional derivative includes ordinary derivatives and approximate derivatives. By using the method of upper and lower solutions and a fixed point theorem, we achieve some results which are the generalizations of some previous results in the literatures. 展开更多
关键词 Periodic Boundary Value Problem Distributional Henstock-Kurzweil integral Distributional DERIVATIVE EXISTENCE UPPER and LOWER Solutions Fixed point
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Precise integration method for a class of singular two-point boundary value problems 被引量:2
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作者 Wen-Zhi Zhang Pei-Yan Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期233-240,共8页
In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the met... In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations(ODEs) are transformed into homogeneous ODEs.Then the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction method.Finally numerical examples are elaboratedd to validate the present method. 展开更多
关键词 Singular two point boundary value problem Precise integration method High order multiple perturbation method Reduction method
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Design of Wind Turbine Torque Controller with Second‑Order Integral Sliding Mode Based on VGWO Algorithm 被引量:3
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作者 MA Leiming XIAO Lingfei +1 位作者 SATTAROV Robert R HUANG Xinhao 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第2期259-270,共12页
A robust control strategy using the second-order integral sliding mode control(SOISMC)based on the variable speed grey wolf optimization(VGWO)is proposed.The aim is to maximize the wind power extraction of wind turbin... A robust control strategy using the second-order integral sliding mode control(SOISMC)based on the variable speed grey wolf optimization(VGWO)is proposed.The aim is to maximize the wind power extraction of wind turbine.Firstly,according to the uncertainty model of wind turbine,a SOISMC torque controller with fast convergence speed,strong robustness and effective chattering reduction is designed,which ensures that the torque controller can effectively track the reference speed.Secondly,given the strong local search ability of the grey wolf optimization(GWO)and the fast convergence speed and strong global search ability of the particle swarm optimization(PSO),the speed component of PSO is introduced into GWO,and VGWO with fast convergence speed,high solution accuracy and strong global search ability is used to optimize the parameters of wind turbine torque controller.Finally,the simulation is implemented based on Simulink/SimPowerSystem.The results demonstrate the effectiveness of the proposed strategy under both external disturbance and model uncertainty. 展开更多
关键词 integral sliding mode second-order sliding mode maximum power point tracking optimization algorithm wind turbine
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SINGULAR INTEGRAL EQUATIONS ON THE REAL AXIS WITH SOLUTIONS HAVING SINGULARITIES OF HIGHER ORDER 被引量:1
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作者 钟寿国 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1093-1099,共7页
We transform the singular integral equations with solutions simultaneously having singularities of higher order at infinite point and at several finite points on the real axis into ones along a closed contour with sol... We transform the singular integral equations with solutions simultaneously having singularities of higher order at infinite point and at several finite points on the real axis into ones along a closed contour with solutions having singularities of higher order, and for the former obtain the extended Neother theorem of complete equation as well as the solutions and the solvable conditions of characteristic equation from the latter. The conclusions drawn by this article contain special cases discussed before. 展开更多
关键词 Singular integral equation solution with singularities of higher order real axis infinite point class ■*λ1 ... λn λ∞
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Existence and Uniqueness of Almost Periodic Solutions for Some Infinite Delay Integral Equations 被引量:1
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作者 XU Jian-zhong ZHANG Yu-chuan ZHOU Zong-fu 《Chinese Quarterly Journal of Mathematics》 2018年第2期166-171,共6页
In this paper, the existence and uniqueness of almost periodic solutions for some infinite delay integral equations are discussed. By using Krasnoselskii fixed point theorem,some new results are obtained.
关键词 Almost periodic solution Existence UNIQUENESS Delay integral equation Krasnoselskii fixed point theorem
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Heat Flux Analysis in Electrical Transformers through Integral Operators of Mechanics 被引量:1
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作者 Francisco Bulnes Alejandro R. Tello Máximo Livera 《Modern Mechanical Engineering》 2014年第2期84-107,共24页
Considering the continuous functioning of a power transformer under charge of high capacity of 50 MVA, predicted studies are proposed to be performed of their thermal behavior under perma nent and variable regimens of... Considering the continuous functioning of a power transformer under charge of high capacity of 50 MVA, predicted studies are proposed to be performed of their thermal behavior under perma nent and variable regimens of flow of charge, using noninvasive methods based in integral trans forms that measure and determine parameters of geometrical, analytical and physical type of the transformer. In before works, we have studied a basic geometry of a winding composed of high and low voltage sections with a uniform heat generation and heat convection boundary conditions. The heat conduction equation representing the phenomena of heat generation in a cylindrical structure was solved by using an integral transform. In this sense, this new study considers the basic geometry composed of a three cylindrical windings (high and low voltage turns) and a rec tangular core. Thus it is proposed to solve magnetic flow equations using integral transforms (Han kel transforms and Bessel integrals) in order to obtain the heat source distribution in the core due to the magnetization currents which are developed in function of the magnetic field flow equations. Based on this, it is proposed as a second step to use this heat source distribution to obtain the corresponding temperature distribution in the core by solving the cylindrical heat conduction equation for the core (cylindrical). Bearing this in mind, it is proposed finally to solve the 3D cylindrical heat conduction equation for the one winding using the calculated heat convection coefficients, the conductivity of the winding, behavior of the mineral oil and the non uniform winding heat generation predicted in recent researches. This equation will be solved by using integral methods (Radon, Hankel and Fourier transforms). This methodology will be useful to establish a new design of a power transformer based on the values of their integrals and the results that throw the inverse methods for this case. Finally if possible we will use the programs of Fluent and/or Phoenics for the validation of functional proposed models of prediction and prevention of heat flow and charge based on the obtained results. 展开更多
关键词 Power Transformer Thermal Model CRITICAL Temperature pointS integral Transforms to Heat FLUX Magnetic FLUX
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Cubature Kalman Filter Under Minimum Error Entropy With Fiducial Points for INS/GPS Integration 被引量:2
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作者 Lujuan Dang Badong Chen +2 位作者 Yulong Huang Yonggang Zhang Haiquan Zhao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第3期450-465,共16页
Traditional cubature Kalman filter(CKF)is a preferable tool for the inertial navigation system(INS)/global positioning system(GPS)integration under Gaussian noises.The CKF,however,may provide a significantly biased es... Traditional cubature Kalman filter(CKF)is a preferable tool for the inertial navigation system(INS)/global positioning system(GPS)integration under Gaussian noises.The CKF,however,may provide a significantly biased estimate when the INS/GPS system suffers from complex non-Gaussian disturbances.To address this issue,a robust nonlinear Kalman filter referred to as cubature Kalman filter under minimum error entropy with fiducial points(MEEF-CKF)is proposed.The MEEF-CKF behaves a strong robustness against complex nonGaussian noises by operating several major steps,i.e.,regression model construction,robust state estimation and free parameters optimization.More concretely,a regression model is constructed with the consideration of residual error caused by linearizing a nonlinear function at the first step.The MEEF-CKF is then developed by solving an optimization problem based on minimum error entropy with fiducial points(MEEF)under the framework of the regression model.In the MEEF-CKF,a novel optimization approach is provided for the purpose of determining free parameters adaptively.In addition,the computational complexity and convergence analyses of the MEEF-CKF are conducted for demonstrating the calculational burden and convergence characteristic.The enhanced robustness of the MEEF-CKF is demonstrated by Monte Carlo simulations on the application of a target tracking with INS/GPS integration under complex nonGaussian noises. 展开更多
关键词 Cubature Kalman filter(CKF) inertial navigation system(INS)/global positioning system(GPS)integration minimum error entropy with fiducial points(MEEF) non-Gaussian noise
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q–differ-integral operator on p–valent functions associated with operator on Hilbert space 被引量:1
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作者 Shahram Najafzadeh 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第3期458-466,共9页
Making use of multivalent functions with negative coefficients of the type f (z)=z^(p)-~(∑)_(k=p+1)^(∞)a_(k)z^(k),which are analytic in the open unit disk and applying the q-derivative a q–differintegral operator i... Making use of multivalent functions with negative coefficients of the type f (z)=z^(p)-~(∑)_(k=p+1)^(∞)a_(k)z^(k),which are analytic in the open unit disk and applying the q-derivative a q–differintegral operator is considered.Furthermore by using the familiar Riesz-Dunford integral,a linear operator on Hilbert space H is introduced.A new subclass of p-valent functions related to an operator on H is defined.Coefficient estimate,distortion bound and extreme points are obtained.The convolution-preserving property is also investigated. 展开更多
关键词 multivalent function fractional q–derivative operator fractional q–integral operator Hilbert space coefficient estimate distortion bound extreme point convolution(or Hadamard product)
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Analytical Properties of Solutions and First Integrals of a Class of the Third-Order Autonomous Systems
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作者 CHEN Yang I.P.Martynov 《重庆理工大学学报(自然科学)》 CAS 北大核心 2018年第6期199-204,共6页
The paper is devoted to the analytic theory of differential equations.In paper shown that how to establish the analytical properties of solutions of an autonomous system of the third order special type(meromorphy of g... The paper is devoted to the analytic theory of differential equations.In paper shown that how to establish the analytical properties of solutions of an autonomous system of the third order special type(meromorphy of general solutions,instances of availability logarithmic branch points).The method for constructing the first integrals of the systems under consideration is indicated. 展开更多
关键词 MEROMORPHIC function logarithmic branch point FIRST integral
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An Adaptive Steganographic Algorithm for Point Geometry Based on Nearest Neighbors Search
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作者 Yuan-Yu Tsai Chi-Shiang Chan 《Journal of Electronic Science and Technology》 CAS 2012年第3期220-226,共7页
In this study, we extend our previous adaptive steganographic algorithm to support point geometry. For the purpose of the vertex decimation process presented in the previous work, the neighboring information between p... In this study, we extend our previous adaptive steganographic algorithm to support point geometry. For the purpose of the vertex decimation process presented in the previous work, the neighboring information between points is necessary. Therefore, a nearest neighbors search scheme, considering the local complexity of the processing point, is used to determinate the neighbors for each point in a point geometry. With the constructed virtual connectivity, the secret message can be embedded successfully after the vertex decimation and data embedding processes. The experimental results show that the proposed algorithm can preserve the advantages of previous work, including higher estimation accuracy, high embedding capacity, acceptable model distortion, and robustness against similarity transformation attacks. Most importantly, this work is the first 3D steganographic algorithm for point geometry with adaptation. 展开更多
关键词 ADAPTATION nearest neighbors search point geometry steganography.
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EIGENVECTORS OF SYSTEM OF HAMMERSTEIN INTEGRAL EQUATIONS IN BANACH SPACES ANDAPPLICATIONS
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作者 娄本东 《Acta Mathematica Scientia》 SCIE CSCD 2000年第1期55-62,共8页
In this paper, the author investigates the existence of eigenvectors of system of Hammerstein integral equations in Banach spaces by means of fixed point index theory. He also gives some applications to a system of S ... In this paper, the author investigates the existence of eigenvectors of system of Hammerstein integral equations in Banach spaces by means of fixed point index theory. He also gives some applications to a system of S turm-Liouville problems of ordinary differential equations. 展开更多
关键词 EIGENVECTORS Hammerstein integral equations fixed point index
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