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X inactive-specific transcript regulates mitochondrial function and neuronal differentiation of stem cells via IGF2BP2/CPT1A axis in models of spinal cord injury
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作者 Si-Xiang Zeng Jin-Tao Ye +1 位作者 Si-Hua Huang Ruo-Xi Liu 《World Journal of Stem Cells》 2025年第7期131-142,共12页
BACKGROUND Spinal cord injury(SCI)often results in irreversible neurological deficits;therefore,effective treatment is urgently needed.Neural stem cells(NSCs)have excellent differentiation potential.However,the role o... BACKGROUND Spinal cord injury(SCI)often results in irreversible neurological deficits;therefore,effective treatment is urgently needed.Neural stem cells(NSCs)have excellent differentiation potential.However,the role of the long noncoding RNA X inactive-specific transcript(XIST)in NSCs and SCI remains unclear.AIM To explore the role of XIST in enhancing NSC function and its therapeutic potential in SCI.METHODS We used in vitro and in vivo models to examine the effects of XIST on NSCs.XIST was overexpressed in NSCs,and its impact on mitochondrial function,neuronal differentiation,and the insulin-like growth factor 2 mRNA binding protein 2(IGF2BP2)/carnitine palmitoyl transferase 1A(CPT1A)pathway was assessed using a series of biochemical assays,quantitative PCR,and Seahorse XF24 analysis.A mouse model of SCI was used to evaluate the therapeutic effects of XIST in vivo.RESULTS Overexpression of XIST in NSCs significantly increased mitochondrial membrane potential,ATP production,and oxygen consumption rate.XIST also promoted NSC proliferation and neuronal differentiation while inhibiting astrocytic differentiation.Mechanistically,XIST regulated CPT1A expression post-transcriptionally by interacting with IGF2BP2.In vivo XIST-treated mice exhibited improved motor scores and reduced proinflammatory cytokine expression following SCI.CONCLUSIONThese findings suggested that XIST modulated mitochondrial function and neural differentiation in NSCs throughthe IGF2BP2/CPT1A pathway. While preliminary in vivo results are encouraging, further studies are needed todetermine the long-term therapeutic relevance and underlying mechanisms of XIST in SCI recovery. 展开更多
关键词 Spinal cord injury Neural stem cell X inactive-specific transcript Mitochondrial function Neuronal differentiation
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Landscape Pattern Characteristics of Plant Species Diversity in Campus Courtyards from the Perspective of Functional Differentiation:A Case Study of the Courtyard at Tongzhou Campus,Renmin University of China
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作者 ZHANG Qi DENG Huiwen YANG Xin 《Journal of Landscape Research》 2025年第4期1-7,16,共8页
This study focuses on the three courtyards located in the eastern,central,and western sections of the Tongzhou Campus of Renmin University of China.Adopting a functional differentiation perspective,the research system... This study focuses on the three courtyards located in the eastern,central,and western sections of the Tongzhou Campus of Renmin University of China.Adopting a functional differentiation perspective,the research systematically analyzes the patterns of plant diversity within courtyards characterized by distinct functional orientations.This analysis employs various plant species diversity indices,including the Patrick richness index,Simpson dominance index,Shannon-Wiener diversity index,and Pielou evenness index,alongside a classification of functional plant types,namely ornamental,ecological regulation,spatial shaping,and recreational assistance.The results indicate that the east courtyard presents the highest Patrick species richness(S=42),predominantly comprising spatial shaping and recreational assistance plants,which are wellsuited for recreational and passage functions.Conversely,the central courtyard exhibits the lowest Patrick species richness(S=19),characterized by a balanced distribution of functional types,with an emphasis on public display and traffic guidance.The west courtyard demonstrates the greatest stability in the tree layer(D=0.87),featuring a combination of shade-tolerant and ornamental plants that fulfill the requirements for a tranquil and naturalistic environment.One-way analysis of variance reveals that only Patrick species richness differs significantly among the courtyards(P=0.007),whereas the diversity index does not show a significant difference.This finding suggests that functional requirements precisely regulate diversity through microhabitat heterogeneity and plant configuration strategies.This study offers both a theoretical foundation and practical guidance for the plant configuration and functional optimization of small-scale courtyards on campus. 展开更多
关键词 Campus courtyard Plant species diversity functional differentiation Tongzhou Campus of Renmin University of China
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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Kunfeng Liang Zhijun Liu Xinru Bao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3033-3049,共17页
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna... Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed. 展开更多
关键词 Population balance equation CRYSTALLIZATION peridynamic differential operator Euler’s first-order explicit method
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Existence and Uniqueness of Positive Periodic Solutions for First-order Functional Differential Equations
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作者 HAN Qian-qian ZHAI Cheng-bo 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第3期454-461,共8页
In this paper, we prove the existence and uniqueness of positive periodic solutions for first-order functional differential equation y'(t) = α(t)y(t) + f(t, y(t -τ-(t))) + g(t)by using two fixed poi... In this paper, we prove the existence and uniqueness of positive periodic solutions for first-order functional differential equation y'(t) = α(t)y(t) + f(t, y(t -τ-(t))) + g(t)by using two fixed point theorems of general α-concave operators and homogeneous operators in ordered Banach spaces. 展开更多
关键词 functional differential equation existence and uniqueness positive periodics olution~ general s-concave operator homogeneous operator
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Dynamic Characteristics of Functionally Graded Timoshenko Beams by Improved Differential Quadrature Method
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作者 Xiaojun Huang Liaojun Zhang +1 位作者 Hanbo Cui Gaoxing Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1647-1668,共22页
This study proposes an effective method to enhance the accuracy of the Differential Quadrature Method(DQM)for calculating the dynamic characteristics of functionally graded beams by improving the form of discrete node... This study proposes an effective method to enhance the accuracy of the Differential Quadrature Method(DQM)for calculating the dynamic characteristics of functionally graded beams by improving the form of discrete node distribution.Firstly,based on the first-order shear deformation theory,the governing equation of free vibration of a functionally graded beam is transformed into the eigenvalue problem of ordinary differential equations with respect to beam axial displacement,transverse displacement,and cross-sectional rotation angle by considering the effects of shear deformation and rotational inertia of the beam cross-section.Then,ignoring the shear deformation of the beam section and only considering the effect of the rotational inertia of the section,the governing equation of the beam is transformed into the eigenvalue problem of ordinary differential equations with respect to beam transverse displacement.Based on the differential quadrature method theory,the eigenvalue problem of ordinary differential equations is transformed into the eigenvalue problem of standard generalized algebraic equations.Finally,the first several natural frequencies of the beam can be calculated.The feasibility and accuracy of the improved DQM are verified using the finite element method(FEM)and combined with the results of relevant literature. 展开更多
关键词 Timoshenko beams functionally graded materials dynamic characteristics natural frequency improved differential quadrature method
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Complements to the Theory of Higher-Order Types of Asymptotic Variation for Differentiable Functions 被引量:1
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作者 Antonio Granata 《Advances in Pure Mathematics》 2019年第5期434-479,共46页
The purpose of this paper is to add some complements to the general theory of higher-order types of asymptotic variation developed in two previous papers so as to complete our elementary (but not too much!) theory in ... The purpose of this paper is to add some complements to the general theory of higher-order types of asymptotic variation developed in two previous papers so as to complete our elementary (but not too much!) theory in view of applications to the theory of finite asymptotic expansions in the real domain, the asymptotic study of ordinary differential equations and the like. The main results concern: 1) a detailed study of the types of asymptotic variation of an infinite series so extending the results known for the sole power series;2) the type of asymptotic variation of a Wronskian completing the many already-published results on the asymptotic behaviors of Wronskians;3) a comparison between the two main standard approaches to the concept of “type of asymptotic variation”: via an asymptotic differential equation or an asymptotic functional equation;4) a discussion about the simple concept of logarithmic variation making explicit and completing the results which, in the literature, are hidden in a quite-complicated general theory. 展开更多
关键词 HIGHER-ORDER Regularly-Varying functionS HIGHER-ORDER Rapidly-Varying functionS Smoothly-Varying functionS Exponentially-Varying functionS Logarithmically-Varying functionS ASYMPTOTIC differential EQUATIONS As-ymptotic functional EQUATIONS ASYMPTOTIC VARIATION of Wronskians
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SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVES BY LAGRANGE INTERPOLATING POLYNOMIALS 被引量:1
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作者 T.F.Xie S.P.Zhou 《Analysis in Theory and Applications》 1994年第4期100-109,共10页
This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of... This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of deereeon the nodes X_nUY_n(see the definition of the next). 展开更多
关键词 SIMULTANEOUSE APPROXIMATION TO A differentiable function AND ITS DERIVATIVES BY LAGRANGE INTERPOLATING POLYNOMIALS APPI ZR
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Calculus of Generalized Quasi-differentiable Functions I: Some Results on the Space of Pairs of Convex-Set Collections 被引量:3
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作者 张宏伟 张立卫 夏尊铨 《Northeastern Mathematical Journal》 CSCD 2003年第1期75-85,共11页
A Riesz space K1 whose elements are pairs of convex-set collections is presented for the study on the calculus of generalized quasi-differentiable functions. The space K1 is constructed by introducing a well-defined e... A Riesz space K1 whose elements are pairs of convex-set collections is presented for the study on the calculus of generalized quasi-differentiable functions. The space K1 is constructed by introducing a well-defined equivalence relation among pairs of collections of convex sets. Some important properties on the norm and operations in K1 are given. 展开更多
关键词 convex-set collection Riesz space quasi-differentiable function quasi-differential
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Star-shaped Differentiable Functions and Star-shaped Differentials
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作者 PAN SHAO-RONG ZHANG HONG-WEI ZHANG LI-WEI 《Communications in Mathematical Research》 CSCD 2010年第1期41-52,共12页
Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defin... Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defined. Formulas for star-shaped differential of a pointwise maximum and a pointwise minimum of a finite number of directionally differentiable functions, and a composite of two directionaUy differentiable functions are derived. Furthermore, the mean-value theorem for a directionaUy differentiable function is demonstrated. 展开更多
关键词 The space of star-shaped sets gauge function isometrical isomorphism directionally differentiable function star-shaped differential mean-value theorem
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Fast First-Order Methods for Minimizing Convex Composite Functions
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作者 Qipeng Li Hongwei Liu Zexian Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第6期46-52,共7页
Two new versions of accelerated first-order methods for minimizing convex composite functions are proposed. In this paper, we first present an accelerated first-order method which chooses the step size 1/ Lk to be 1/ ... Two new versions of accelerated first-order methods for minimizing convex composite functions are proposed. In this paper, we first present an accelerated first-order method which chooses the step size 1/ Lk to be 1/ L0 at the beginning of each iteration and preserves the computational simplicity of the fast iterative shrinkage-thresholding algorithm. The first proposed algorithm is a non-monotone algorithm. To avoid this behavior, we present another accelerated monotone first-order method. The proposed two accelerated first-order methods are proved to have a better convergence rate for minimizing convex composite functions. Numerical results demonstrate the efficiency of the proposed two accelerated first-order methods. 展开更多
关键词 first-order method iterative shrinkage-thresholding algorithm convex programming adaptive restart composite functions.
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A Direct Calculation of First-Order Wave Function of Helium
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作者 Boniface Otieno Ndinya Joseph Akeyo Omolo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期647-650,共4页
We develop a simple analytic calculation for the first order wave function of helium in a model in which nuclear charge screening is caused by repulsive coulomb interaction. The perturbation term, first-order correlat... We develop a simple analytic calculation for the first order wave function of helium in a model in which nuclear charge screening is caused by repulsive coulomb interaction. The perturbation term, first-order correlation energy, and first-order wave function are divided into two components, one component associated with the repulsive coulomb interaction and the other proportional to magnetic shielding. The resulting first-order wave functions are applied to calculate second-order energies within the model. We find that the second-order energies are independent of the nuclear charge screening constant in the unperturbed Hamiltonian with a central coulomb potential. 展开更多
关键词 nuclear charge screening first-order wave function and second-order energy
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Optimal Lagrange Interpolation of a Class of Infinitely Differentiable Functions
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作者 Mengjin MA Hui WANG Guiqiao XU 《Journal of Mathematical Research with Applications》 CSCD 2021年第6期629-638,共10页
This paper investigates the optimal Lagrange interpolation of a class F∞of infinitely differentiable functions on[-1,1]in L_(∞)[-1,1]and weighted spaces L_(p,ω)[-1,1],1≤p<∞withωa continuous integrable weight ... This paper investigates the optimal Lagrange interpolation of a class F∞of infinitely differentiable functions on[-1,1]in L_(∞)[-1,1]and weighted spaces L_(p,ω)[-1,1],1≤p<∞withωa continuous integrable weight function in(-1,1).We proved that the Lagrange interpolation polynomials based on the zeros of polynomials with the leading coefficient 1 of the least deviation from zero in L_(p,ω)[-1,1]are optimal for 1≤p<∞.We also give the optimal Lagrange interpolation nodes when the endpoints are included in the nodes. 展开更多
关键词 worst case setting optimal Lagrange interpolation infinitely differentiable function space
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THE CONTINUAL DIFFERENTIABLE PEAK-UNIMODAL SOLUTIONS OF FEIGENBAUM’S FUNCTIONAL EQUATIONS
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作者 程宝龙 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第5期419-426,共8页
For the famous Feigenbaum's equations, in this paper, we established its constructive theorem of the peak-unimodal, then we found out other paths to explore the peak-unimodal solutions. For example, we proceed on ... For the famous Feigenbaum's equations, in this paper, we established its constructive theorem of the peak-unimodal, then we found out other paths to explore the peak-unimodal solutions. For example, we proceed on the direction to try the non-symmetrical continuous peak-unimodal solutions and C1 solutions. 展开更多
关键词 THE CONTINUAL differentiable PEAK-UNIMODAL SOLUTIONS OF FEIGENBAUM S functionAL EQUATIONS
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Finite Element Approach for the Solution of First-Order Differential Equations
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作者 André Schmidt Horst R. Beyer +1 位作者 Matthias Hinze Evangelos N. Vandoros 《Journal of Applied Mathematics and Physics》 2020年第10期2072-2090,共19页
The finite element method has established itself as an efficient numerical procedure for the solution of arbitrary-shaped field problems in space. Basically, the finite element method transforms the underlying differe... The finite element method has established itself as an efficient numerical procedure for the solution of arbitrary-shaped field problems in space. Basically, the finite element method transforms the underlying differential equation into a system of algebraic equations by application of the method of weighted residuals in conjunction with a finite element ansatz. However, this procedure is restricted to even-ordered differential equations and leads to symmetric system matrices as a key property of the finite element method. This paper aims in a generalization of the finite element method towards the solution of first-order differential equations. This is achieved by an approach which replaces the first-order derivative by fractional powers of operators making use of the square root of a Sturm-Liouville operator. The resulting procedure incorporates a finite element formulation and leads to a symmetric but dense system matrix. Finally, the scheme is applied to the barometric equation where the results are compared with the analytical solution and other numerical approaches. It turns out that the resulting numerical scheme shows excellent convergence properties. 展开更多
关键词 Finite Element Method first-order differential Equations Fractional Powers of Operators
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ON SIMULTANEOUS APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVE BY INVERSE PAL-TYPE INTERPOLATION POLYNOMIALS
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作者 Bao Yongguang (Hangzhou University, China) 《Analysis in Theory and Applications》 1995年第4期15-23,共9页
Let ξn-1<ξn-2 <ξn-2 <… < ξ1 be the zeros of the the (n -1)-th Legendre polynomial Pn-1(x) and - 1 = xn < xn-1 <… < x1 = 1 the zeros of the polynomial W n(x) =- n(n - 1) Pn-1(t)dt = (1 -x2)P&... Let ξn-1<ξn-2 <ξn-2 <… < ξ1 be the zeros of the the (n -1)-th Legendre polynomial Pn-1(x) and - 1 = xn < xn-1 <… < x1 = 1 the zeros of the polynomial W n(x) =- n(n - 1) Pn-1(t)dt = (1 -x2)P'n-1(x). By the theory of the inverse Pal-Type interpolation, for a function f(x) ∈ C[-1 1], there exists a unique polynomial Rn(x) of degree 2n - 2 (if n is even) satisfying conditions Rn(f,ξk) = f(∈ek)(1≤ k≤ n - 1) ;R'n(f,xk) = f'(xk)(1≤ k≤ n). This paper discusses the simultaneous approximation to a differentiable function f by inverse Pal-Type interpolation polynomial {Rn(f,x)} (n is even) and the main result of this paper is that if f ∈ C'[1,1], r≥2, n≥ + 2> and n is even thenholds uniformly for all x ∈ [- 1,1], where h(x) = 1 + 展开更多
关键词 MATH In ON SIMULTANEOUS APPROXIMATION TO A differentiable function AND ITS DERIVATIVE BY INVERSE PAL-TYPE INTERPOLATION POLYNOMIALS PAL ITS
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MEROMORPHIC SOLUTIONS OF DELAY SCHWARZIAN DIFFERENTIAL EQUATIONS
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作者 Xiaotang NIE Jiaxing HUANG +1 位作者 Yuefei WANG CHENGFA WU 《Acta Mathematica Scientia》 2025年第4期1514-1528,共15页
In this paper,we focus on the admissible transcendental meromorphic solutions of the following delay Schwarzian differential equations with rational coefficients f(z+1)-f(z-1)+a(z)S(f,z)=P(z,f(z))/Q(z,f(z)).We obtain ... In this paper,we focus on the admissible transcendental meromorphic solutions of the following delay Schwarzian differential equations with rational coefficients f(z+1)-f(z-1)+a(z)S(f,z)=P(z,f(z))/Q(z,f(z)).We obtain the necessary conditions on the degree of R(z,f)for these delay differential equations and give a classification of the delay Schwarzian differential equations according to the multiplicities of the root of Q(z,f)on f.Finally,we provide some examples to illustrate that all cases occur. 展开更多
关键词 meromorphic functions delay differential equations Nevanlinna theory Schwarzian derivatives minimal hyper-type
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PSEUDO S-ASYMPTOTICALLY PERIODIC SOLUTIONS OF PARTIAL NEUTRAL DIFFERENTIAL EQUATIONS
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作者 LIU Jing-huai ZHANG Li-tao 《数学杂志》 2025年第2期140-150,共11页
In this paper,we study the existence of pseudo S-asymptotically ω-periodic mild solutions of abstract partial neutral differential equations in Banach spaces.By using the principle of Banach contractive mapping,the e... In this paper,we study the existence of pseudo S-asymptotically ω-periodic mild solutions of abstract partial neutral differential equations in Banach spaces.By using the principle of Banach contractive mapping,the existence and uniqueness of pseudo S-asymptotically ω-periodic mild solutions of abstract partial neutral differential equations are obtained.To illustrate the ab-stract result,a concrete example is given. 展开更多
关键词 pseudo S-asymptotically!-periodic function mild solution partial neutral differential equations
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Existence of Periodic Solutions for Generalized Liénard-Typed Functional Differential Equations
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作者 贺小明 葛渭高 单文锐 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期325-328,共4页
The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are ... The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are established for the existence of periodic solutions and some previous results are extended. 展开更多
关键词 functional differential equation periodic solution coincidence degree
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The Global Solutions of Impulsive Retarded Functional Differential Equations
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作者 王儒智 孙建安 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期94-99,共6页
In this paper, we present some results on the existence of the golbal solutions of nonlinear impulsive retarded functional differential equations.
关键词 Fréchet spaces Tychonoff fixed point Theorem impulsive retarded functional differential equations
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THE BASIC THEORY OF SOLUTIONS OF FUNCTIONAL DIFFERENTIAL EQUATIONS WITH BOUNDED DELAY IN THE SPACE OF INTEGRABLE FUNCTIONS
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作者 刘永清 李远清 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 1997年第7期67-73,共7页
在可积函数空间中讨论有界滞量泛函微分方程,建立其解的基本理论,包括解的存在性,唯一性及延展性。
关键词 有界滞量的泛函微分方程 存在性 唯一性 延展性 可积函数空间
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