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Uniqueness of the Viscosity Solutions for the Initial Value Problem of One Type of Second Order Partial Differential Equation
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作者 刘长河 郇中丹 童明生 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期6-11,共6页
Aim To prove the uniqueness of the viscosity solutions for the initial value problems of one type of second order parabolic partial differential equations: Methods Using comparison theorem. Results and Conclusion If u... Aim To prove the uniqueness of the viscosity solutions for the initial value problems of one type of second order parabolic partial differential equations: Methods Using comparison theorem. Results and Conclusion If u0 is uniform continuousfunction in RN , F is continuous function in RNx(N) and F is degenerate elliptic, then thisequation has the sole viscosity solution. 展开更多
关键词 viscosity solution degenerate ellipticity the uniqueness of the solutions
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基于Valued ERGMs模型的核心技术网络成长机制研究——以量子计算领域为例 被引量:2
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作者 任海英 李真 《科技进步与对策》 CSSCI 北大核心 2024年第4期1-11,共11页
对核心技术网络及其成长机制的研究有助于梳理核心技术之间的依赖和促进关系,为研究核心技术演化提供新的理论视角和方法。以技术演化相关理论为基础,归纳核心技术网络成长的影响因素,基于量子计算领域专利数据,识别以技术概念和技术关... 对核心技术网络及其成长机制的研究有助于梳理核心技术之间的依赖和促进关系,为研究核心技术演化提供新的理论视角和方法。以技术演化相关理论为基础,归纳核心技术网络成长的影响因素,基于量子计算领域专利数据,识别以技术概念和技术关系为基础的量子计算领域核心技术网络,并基于Valued ERGMs模型构建核心技术网络成长机制模型。结果表明,技术要素中心性、专利技术研发能力、与TRIZ进化法则匹配程度以及技术要素同配性对核心技术网络成长具有正向促进作用;在技术路径方面,核心技术网络成长受到技术要素路径依赖性和技术突破的双重影响。最后,根据量子计算领域核心技术网络成长机制的实证研究结果,从技术研发层面、企业层面、政府层面为相关领域技术发展提出策略建议。 展开更多
关键词 技术演化 核心技术网络 技术网络成长机制 valued ERGMs模型 量子计算
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弹性退休制度下谁更愿意延迟退休?——基于Option Value模型的微观模拟
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作者 郭秀云 李悦心 《人口与发展》 CSSCI 北大核心 2024年第4期132-144,共13页
人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、... 人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、内部报酬率进行模拟。研究发现:养老金总财富随退休年龄“先增后减”,男性的峰值年龄早于女性;引入养老金“奖惩”机制有助于提高最优退休年龄,激励劳动者延迟退休;考虑闲暇偏好的异质性,男性参保者更倾向于早退休,而女性参保者特别是女性较高收入群体更愿意延迟退休;厌恶风险的参保者更有可能选择早退休。建议尽早建立弹性退休年龄政策体系,增加劳动者的选择权和制度灵活性;引入精算调节因子构建养老金奖惩机制,完善养老保险待遇计发办法。 展开更多
关键词 延迟退休 养老金财富 Option value模型
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UNIQUENESS OF ENTIRE FUNCTIONS SHARING ONE VALUE 被引量:6
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作者 林秀清 林伟川 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1062-1076,共15页
We deal with the problem of entire functions sharing one value weakly. Moreover, we improve and generalize some former results obtained by J.-F.Chen, et al. [6], Y.Xu and H.L.Qiu [4], M.L. Fang [5], C.C. Yang, and X.H... We deal with the problem of entire functions sharing one value weakly. Moreover, we improve and generalize some former results obtained by J.-F.Chen, et al. [6], Y.Xu and H.L.Qiu [4], M.L. Fang [5], C.C. Yang, and X.H. Hua [3]. 展开更多
关键词 uniqueNESS entire function shared value meromorphic function
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EXISTENCE AND UNIQUENESS FOR THIRD ORDER NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:5
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作者 WANG GUOCAN Department of Basic Science, Dalian Institute of Railway Technology, Dalian 116022 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期7-16,共10页
In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower soluti... In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower solutions. Our results improve someknown works. 展开更多
关键词 Third order nonlinear boundary value problem existence and uniqueness Volterra type operator upper and lower solutions.
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EXISTENCE AND UNIQUENESS RESULTS FOR BOUNDARY VALUE PROBLEMS OF HIGHER ORDER FRACTIONAL INTEGRO-DIFFERENTIAL EQUATIONS INVOLVING GRONWALL'S INEQUALITY IN BANACH SPACES 被引量:2
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作者 Dimplekumar N. CHALISHAJAR K. KARTHIKEYAN 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期758-772,共15页
We study boundary value problems for fractional integro-differential equations involving Caputo derivative of order α∈ (n-1, n) in Banach spaces. Existence and uniqueness results of solutions are established by vi... We study boundary value problems for fractional integro-differential equations involving Caputo derivative of order α∈ (n-1, n) in Banach spaces. Existence and uniqueness results of solutions are established by virtue of the Holder's inequality, a suitable singular Cronwall's inequality and fixed point theorem via a priori estimate method. At last, examples are given to illustrate the results. 展开更多
关键词 Boundary value problems fractional order integro-differential equations bound-ary value problems existence and uniqueness singular gronwall inequality fixed point theorem
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Existence and Uniqueness of Solutions for Higher Order Nonlinear Multi-point Boundary Value Problems 被引量:7
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作者 PEI Ming-he Sung-Kag Chang 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第2期258-266,共9页
In this paper, the existence and uniqueness theorems of solutions of k-point boundary value problems for nth-order nonlinear differential equations are established by Leray-Schauder continuation theorem.
关键词 nth-order nonlinear differential equations k-point boundary value problem EXISTENCE uniqueNESS
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UNIQUENESS FOR SOLUTIONS OF NONHOMOGENEOUS A -HARMONIC EQUATIONS WITH VERY WEAK BOUNDARY VALUES 被引量:2
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作者 高红亚 叶玉全 谢素英 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期78-80,共3页
A uniqueness result for nonhomogeneous quasilinear elliptic partial differential equations with very weak boundary values was proved.
关键词 uniqueNESS A harmonic equation weak solution very weak boundary values
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EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTION FOR NONLINEAR SINGULAR 2mth-ORDER CONTINUOUS AND DISCRETE LIDSTONE BOUNDARY VALUE PROBLEMS 被引量:1
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作者 苑成军 文香丹 蒋达清 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期281-291,共11页
By fixed point theorem of a mixed monotone operators, we study Lidstone boundary value problems to nonlinear singular 2mth-order differential and difference equations, and provide sufficient conditions for the existen... By fixed point theorem of a mixed monotone operators, we study Lidstone boundary value problems to nonlinear singular 2mth-order differential and difference equations, and provide sufficient conditions for the existence and uniqueness of positive solution to Lidstone boundary value problem for 2mth-order ordinary differential equations and 2mth-order difference equations. The nonlinear term in the differential and difference equation may be singular. 展开更多
关键词 Mixed monotone operator fixed point theorem boundary value problems existence uniqueNESS
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UNIQUENESS OF MEROMORPHIC FUNCTIONS WHOSE NONLINEAR DIFFERENTIAL POLYNOMIALS SHARE ONE VALUE OR HAVE THE SAME FIXED POINTS IN AN ANGULAR DOMAIN 被引量:1
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作者 李效敏 仪洪勋 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期593-609,共17页
In this article, we study the uniqueness question of nonconstant meromorphic functions whose nonlinear differential polynomials share 1 or have the same fixed points in an angular domain. The results in this article i... In this article, we study the uniqueness question of nonconstant meromorphic functions whose nonlinear differential polynomials share 1 or have the same fixed points in an angular domain. The results in this article improve Theorem 1 of Yang and Hua [26], and improve Theorem 1 of Fang and Qiu [6]. 展开更多
关键词 Meromorphic functions shared values singular directions uniqueness theo-reins in the angular domain
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Uniqueness Problems for Meromorphic Functions that Share Three Values 被引量:1
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作者 WANGJian-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第1期42-46,共5页
This paper investigate the uniqueness problems for meromorphic functions that share three values CM and proves a uniqueness theorem on this topic which can be used to improve some previous related results.
关键词 meromorphic function small function uniqueNESS shared values
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The Existence and Uniqueness of Solutions to Systems of Second-order Ordinary Differential Equations Boundary Value Problem in Absract Space 被引量:2
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作者 武力兵 孙涛 何希勤 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期573-577,共5页
In this paper, it is discussed by using cone and upper and lower solutions mono- tone iterative theory of mixed monotone operator that the bounary value problem is more generalized style to system of equations in the ... In this paper, it is discussed by using cone and upper and lower solutions mono- tone iterative theory of mixed monotone operator that the bounary value problem is more generalized style to system of equations in the form of -u = f(t, u, v) -v = g(t, u, v) u(0) = u(1) = 0 v(0) = v(1) = 0 in abstract space. Moreover, it is obtained unique solutions for system of equations and error estimations between approximation iteration sequence and exact solution under more simpler conditions. Therefore, some new results which extend and improve the related known works in the literatures are obtained. 展开更多
关键词 systems of equations bounary value problem CONE approximation solution
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The Uniqueness of Meromorphic Functions with Common Range Sets and Deficient Values 被引量:2
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作者 LUWei-ran WANGJun 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第1期13-16,共4页
In this paper, the uniqueness of meromorphic functions with common range sets and deficient values are studied. This result is related to a question of Gross.
关键词 meromorphic function uniqueNESS sharing sets
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B-Implicit Contractive Conditions and Unique(Common) Fixed Points on Complex Valued Metric Spaces 被引量:2
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作者 PIAO Yong-jie 《Chinese Quarterly Journal of Mathematics》 2018年第2期212-220,共9页
A class B of complex functions is introduced and several existence theorems of unique(common) fixed points for mappings satisfying a B-implicit contraction are presented.Moreover, the existence results of common fixed... A class B of complex functions is introduced and several existence theorems of unique(common) fixed points for mappings satisfying a B-implicit contraction are presented.Moreover, the existence results of common fixed points for two mappings on a nonempty set with two complex valued metrics are provided. Our outcomes generalize and improve some known results, especially, for instance, Banach contraction principle, Chatterjea-type fixed point theorem and the corresponding fixed point theorems. 展开更多
关键词 Complex valued metric space (Common) Fixed point B-implicit contraction
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THE VALUE DISTRIBUTION AND UNIQUENESS OF ONE CERTAIN TYPE OF DIFFERENTIAL-DIFFERENCE POLYNOMIALS
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作者 张克玉 仪洪勋 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期719-728,共10页
In this article, we investigate the distribution of the zeros and uniqueness of differential-difference polynomialsG(z)=(f^n(f^m(z)-1)∏j=1^d f(z+cj)^vj)^(k)-α(z),H(z)=(f^n(f(z)-1)^m∏j=1^d f(z... In this article, we investigate the distribution of the zeros and uniqueness of differential-difference polynomialsG(z)=(f^n(f^m(z)-1)∏j=1^d f(z+cj)^vj)^(k)-α(z),H(z)=(f^n(f(z)-1)^m∏j=1^d f(z+cj)^vj)^(k)-α(z),where f is transcendental entire function of finite order, cj(j = 1,2,…,d), n,m,d, and vj(j = 1, 2,… , d) are integers, and obtain some theorems, which extended and improved many previous results. 展开更多
关键词 MEROMORPHIC uniqueNESS value distribution differential-difference
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On Uniqueness Problem of Meromorphic Functions Sharing Values with Their q-shifts
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作者 ZHANG Shui-ying LIU Hui-fang 《Chinese Quarterly Journal of Mathematics》 2019年第3期232-241,共10页
In this paper, the uniqueness problems on meromorphic function f(z) of zero order sharing values with their q-shift f(qz + c) are studied. It is shown that if f(z) and f(qz + c) share one values CM and IM respectively... In this paper, the uniqueness problems on meromorphic function f(z) of zero order sharing values with their q-shift f(qz + c) are studied. It is shown that if f(z) and f(qz + c) share one values CM and IM respectively, or share four values partially, then they are identical under an appropriate deficiency assumption. 展开更多
关键词 MEROMORPHIC Function uniqueNESS SHARED value SHIFT
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UNIQUENESS OF SOLUTIONS OF SINGULARLY PERTURBED BOUNDARY VALUE PROBLEMS FOR THIRD QRDER NONLINEAR ORDINARY DIFFERENTIAL EQUATIONS
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作者 赵为礼 《Acta Mathematica Scientia》 SCIE CSCD 1992年第3期304-307,共4页
By making use of the differential inequalities, in this paper we study the uniqueness of solutions of the two kinds of the singularly perturbed boundary value problems for the nonlinear third order ordinary differenti... By making use of the differential inequalities, in this paper we study the uniqueness of solutions of the two kinds of the singularly perturbed boundary value problems for the nonlinear third order ordinary differential equation with a small parameter ε>0: where i=1, 2; a(?)(ε), β(ε) and γ(ε) are functions defined on (0, ε_o], while ε_o>0 is a constant.This paper is the continuation of our works [4, 6]. 展开更多
关键词 uniqueNESS OF SOLUTIONS OF SINGULARLY PERTURBED BOUNDARY value PROBLEMS FOR THIRD QRDER NONLINEAR ORDINARY DIFFERENTIAL EQUATIONS BVP
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Uniqueness of Meromorphic Functions of Differential Polynomials Sharing Two Values IM
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作者 Xinhua Shi 《Advances in Pure Mathematics》 2014年第2期35-41,共7页
In this paper, we shall study the uniqueness problems of meromorphic functions of differential polynomials sharing two values IM. Our results improve or generalize many previous results on value sharing of meromorphic... In this paper, we shall study the uniqueness problems of meromorphic functions of differential polynomials sharing two values IM. Our results improve or generalize many previous results on value sharing of meromorphic functions. 展开更多
关键词 Differential POLYNOMIAL uniqueNESS MEROMORPHIC Function SHARED value
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EXISTENCE AND UNIQUENESS FOR SECOND-ORDER VECTOR BOUNDARY VALUE PROBLEM OF NONLINEAR SYSTEMS
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作者 Du Zengji Lin Xiaojie Ge Weigao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第3期323-330,共8页
This paper is concerned with the following second-order vector boundary value problem :x^R=f(t,Sx,x,x'),0〈t〈1,x(0)=A,g(x(1),x'(1))=B,where x,f,g,A and B are n-vectors. Under appropriate assumptions,exis... This paper is concerned with the following second-order vector boundary value problem :x^R=f(t,Sx,x,x'),0〈t〈1,x(0)=A,g(x(1),x'(1))=B,where x,f,g,A and B are n-vectors. Under appropriate assumptions,existence and uniqueness of solutions are obtained by using upper and lower solutions method. 展开更多
关键词 vector differential equation nonlinear boundary value problem existence and uniqueness upper and lower solutions method.
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Uniqueness theorem,theorem of reciprocity,and eigenvalue problems in linear theory of porous piezoelectricity
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作者 A.K.VASHISHTH V.GUPTA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第4期479-494,共16页
The uniqueness theorem and the theorem of reciprocity in the linearized porous piezoelectricity are established under the assumption of positive definiteness of elastic and electric fields. General theorems in the lin... The uniqueness theorem and the theorem of reciprocity in the linearized porous piezoelectricity are established under the assumption of positive definiteness of elastic and electric fields. General theorems in the linear theory of porous piezoelectric materials are proved for the quasi-static electric field approximation. The uniqueness theorem is also proved without using the positive definiteness of the elastic field. An eigenvalue problem associated with free vibrations of a porous piezoelectric body is stud- ied using the abstract formulation. Some properties of operators are also proved. The problem of frequency shift due to small disturbances, based on an abstract formulation, is studied using a variational and operator approach. A perturbation analysis of a special ease is also given. 展开更多
关键词 eigenvalue problem PIEZOELECTRICITY POROUS uniqueness theorem reciprocal theorem
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