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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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MARTINGALE SOLUTIONS OF FRACTIONAL STOCHASTIC REACTION-DIFFUSION EQUATIONS DRIVEN BY SUPERLINEAR NOISE
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作者 Bixiang WANG 《Acta Mathematica Scientia》 2025年第6期2549-2578,共30页
In this paper,we prove the existence of martingale solutions of a class of stochastic equations with a monotone drift of polynomial growth of arbitrary order and a continuous diffusion term with superlinear growth.Bot... In this paper,we prove the existence of martingale solutions of a class of stochastic equations with a monotone drift of polynomial growth of arbitrary order and a continuous diffusion term with superlinear growth.Both the nonlinear drift and diffusion terms are not required to be locally Lipschitz continuous.We then apply the abstract result to establish the existence of martingale solutions of the fractional stochastic reaction-diffusion equation with polynomial drift driven by a superlinear noise.The pseudo-monotonicity techniques and the Skorokhod-Jakubowski representation theorem in a topological space are used to pass to the limit of a sequence of approximate solutions defined by the Galerkin method. 展开更多
关键词 Martingale solution pseudo-monotonicity superlinear noise Skorokhod-Jakubowski theorem fractional equation stochastic reaction-diffusion equation
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Existence of Multiple Solutions for a Superlinear Sturm Liouville BVPs
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作者 孙伟平 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期1-4,共4页
The existence of solutions of a Sturm Liouville boundary value problem(BVP) for u″+g(u)=p(t,u,u′)(0≤t≤1) is studied by using a continuation theorem based on the topological degree theory. Under the condition that... The existence of solutions of a Sturm Liouville boundary value problem(BVP) for u″+g(u)=p(t,u,u′)(0≤t≤1) is studied by using a continuation theorem based on the topological degree theory. Under the condition that g grows superlinearly and p grows with respect to u and u′ linearly at most, the boundary value problem has an infinitude of solutions. 展开更多
关键词 continuation theorem topological degree superlinearity
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带非正次线性中立项和分布偏差变元的奇阶微分方程的振动性
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作者 林文贤 《浙江大学学报(理学版)》 北大核心 2026年第1期57-62,共6页
研究一类具有非正次线性中立项和分布偏差变元的奇阶微分方程的振动性,利用比较方法和积分技巧建立了若干新的振动准则,推广了相关文献的结论,并通过举例说明了结果的有效性。
关键词 振动性 奇阶 微分方程 非正中立项 次线性中立项
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MULTIPLE POSITIVE SOLUTIONS TO SINGULAR BOUNDARY VALUE PROBLEMS FOR SUPERLINEAR SECOND ORDER ODES 被引量:12
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作者 蒋达清 《Acta Mathematica Scientia》 SCIE CSCD 2002年第2期199-206,共8页
This paper deals with the existence of positive solutions to the singular boundary value problemwhere q(t) may be singular at t = 0 and t = 1, f(t,y) may be superlinear at y =∞ and singular, at y = 0.
关键词 Singular boundary value problem existence superlinear the fixed point theorem
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RELATIVE ENTROPY AND LARGE DEVIATIONS UNDER SUBLINEAR EXPECTATIONS 被引量:6
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作者 高付清 徐明周 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1826-1834,共9页
We give a definition of relative entropy with respect to a sublinear expectation and establish large deviation principle for the empirical measures for independent random variables under the sublinear expectation.
关键词 sublinear expectation relative entropy large deviation empirical measure
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EXISTENCE OF SOLUTIONS FOR NON-PERIODIC SUPERLINEAR SCHRDINGER EQUATIONS WITHOUT (AR) CONDITION 被引量:3
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作者 万莉莉 唐春雷 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1559-1570,共12页
The existence of solutions is obtained for a class of the non-periodic SchrSdinger equation -△u + V(x)u = f(x,u), x E RN, by the generalized mountain pass theorem, where V is large at infinity and f is superline... The existence of solutions is obtained for a class of the non-periodic SchrSdinger equation -△u + V(x)u = f(x,u), x E RN, by the generalized mountain pass theorem, where V is large at infinity and f is superlinear as |u|→ ∞. 展开更多
关键词 Schroedinger equation superlinear generalized mountain pass theorem
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A QP-FREE AND SUPERLINEARLY CONVERGENT ALGORITHM FOR INEQUALITY CONSTRAINED OPTIMIZATIONS 被引量:3
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作者 徐以凡 王薇 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期121-130,共10页
In this paper, a new mixed quasi-Newton method for inequality constrained optimization problems is proposed. The feature of the method is that only the systems of linear equations are solved in each iteration, other t... In this paper, a new mixed quasi-Newton method for inequality constrained optimization problems is proposed. The feature of the method is that only the systems of linear equations are solved in each iteration, other than the quadratic programming, which decrease the amount of computations and is also efficient for large scale problem. Under some mild assumptions without the strict complementary condition., the method is globally and superlinearly convergent. 展开更多
关键词 quasi-Newton method strict complementary condition global convergence superlinear convergence
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A SUPERLINEARLY CONVERGENT TRUST REGION ALGORITHM FOR LC^1 CONSTRAINED OPTIMIZATION PROBLEMS 被引量:3
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作者 欧宜贵 侯定丕 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期67-80,共14页
In this paper, a new trust region algorithm for nonlinear equality constrained LC1 optimization problems is given. It obtains a search direction at each iteration not by solving a quadratic programming subprobiem with... In this paper, a new trust region algorithm for nonlinear equality constrained LC1 optimization problems is given. It obtains a search direction at each iteration not by solving a quadratic programming subprobiem with a trust region bound, but by solving a system of linear equations. Since the computational complexity of a QP-Problem is in general much larger than that of a system of linear equations, this method proposed in this paper may reduce the computational complexity and hence improve computational efficiency. Furthermore, it is proved under appropriate assumptions that this algorithm is globally and super-linearly convergent to a solution of the original problem. Some numerical examples are reported, showing the proposed algorithm can be beneficial from a computational point of view. 展开更多
关键词 LC1 optimization ODE methods trust region methods superlinear convergence
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Existence of Positive Solution for Superlinear Semipositone Singular Second-order m-point Boundary Value Problem 被引量:4
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作者 ZHANG Xing-qiu 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期151-158,共8页
By applying fixed point theorem, the existence of positive solution is considered for superlinear semipositone singular m-point boundary value problem -(Lφ)(x)=(p(x)φ′(x))′+q(x)φ(x) and ξi ∈ (0,... By applying fixed point theorem, the existence of positive solution is considered for superlinear semipositone singular m-point boundary value problem -(Lφ)(x)=(p(x)φ′(x))′+q(x)φ(x) and ξi ∈ (0,1)with 0〈ξ1〈ξ2……〈ξm-2〈1,αi ∈ R^+,f ∈C[(0,1)×R^+,R^+],f(x,φ) may be singular at x=0 and x=1,g(x):(0,1)→R is Lebesgue measurable, g may tend to negative infinity and have finitely many singularities. 展开更多
关键词 SEMIPOSITONE superlinear singular m-point boundary value fixed point theo-rem positive solution
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MULTIPLE POSITIVE SOLUTIONS FOR FIRST ORDER IMPULSIVE SUPERLINEAR INTEGRO-DIFFERENTIAL EQUATIONS ON THE HALF LINE 被引量:3
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作者 Guo Dajun 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1167-1178,共12页
In this paper, the author discusses the multiple positive solutions for an infinite boundary value problem of first order impulsive superlinear integro-differential equations on the half line by means of the fixed poi... In this paper, the author discusses the multiple positive solutions for an infinite boundary value problem of first order impulsive superlinear integro-differential equations on the half line by means of the fixed point theorem of cone expansion and compression with norm type. 展开更多
关键词 impulsive superlinear integro-differential equation infinite boundary value problem fixed point theorem of cone expansion and compression with norm type
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A GLOBALLY AND SUPERLINEARLY CONVERGENT TRUST REGION METHOD FOR LC^1 OPTIMIZATION PROBLEMS 被引量:1
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作者 Zhang Liping Lai Yanlian Institute of Applied Mathematics,Academia Sinica,Beijing 100080. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期72-80,共9页
A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assum... A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assumptions. 展开更多
关键词 LC 1 optimization problem global and superlinear convergence trust region method.
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An Oscillation Criterion for Second Order Superlinear Differential Equations 被引量:6
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作者 陈文灯 俞元洪 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第3期1-6, ,共6页
A new criterion is established for the oscillation of second order superlinear ordinary differential equations of the formx″(t) + p(t)x′(t) + q(t)|x(t)|αsgnx(t) = 0, t ≥ t0,where α>1,p and q are continuous f... A new criterion is established for the oscillation of second order superlinear ordinary differential equations of the formx″(t) + p(t)x′(t) + q(t)|x(t)|αsgnx(t) = 0, t ≥ t0,where α>1,p and q are continuous functions on[t0,∞). This criterion extends and unifies some of the results obtained in [1]- [5]. 展开更多
关键词 superlinearity oscillation criterion second order differential equation
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A SIGN CHANGING SOLUTION FOR ELLIPTIC EQUATION WITH SUBLINEAR TERM AT ORIGIN
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作者 Wu Shaoping Sun Yijing Dept. of Math., Zhejiang Univ., Hangzhou 310027. Nankai Institute of Math., Nankai Univ., Tianjin 300071. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期11-18,共8页
It is proved that the semilinear elliptic problem with zero boundary value -Δ u=λu-|u| q-1 u has a changing sign solution, as q∈(0,1) and λ>λ 2 , where λ 2 is the second eigenvalue of the ... It is proved that the semilinear elliptic problem with zero boundary value -Δ u=λu-|u| q-1 u has a changing sign solution, as q∈(0,1) and λ>λ 2 , where λ 2 is the second eigenvalue of the operator -Δ in the space H 1 0(Ω). 展开更多
关键词 Sign changing solution elliptic equation sublinear term.
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Positive solutions of singular superlinear fourth order boundary value problem
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作者 孔令彬 乔兴昊 关江 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第4期504-506,共3页
The cone theorem and the fixed point index are used to investigate the positive solution of singular superlinear boundary value problem for a fourth order nonlinear differential equation.
关键词 positive solution superlinearity CONE fixed point index
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A SUPERLINEARLY CONVERGENT SPLITTING FEASIBLE SEQUENTIAL QUADRATIC OPTIMIZATION METHOD FOR TWO-BLOCK LARGE-SCALE SMOOTH OPTIMIZATION
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作者 简金宝 张晨 刘鹏杰 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期1-24,共24页
This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method fo... This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising. 展开更多
关键词 large scale optimization two-block smooth optimization splitting method feasible sequential quadratic optimization method superlinear convergence
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具有次线性中立项的二阶微分方程的振动性
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作者 赵玉萍 《四川师范大学学报(自然科学版)》 CAS 2025年第1期138-142,共5页
为进一步发展和完善微分方程的振动理论,研究一类具有次线性中立项的二阶非线性微分方程的振动性,利用Riccati变换、不等式技巧和分析性质,获得该类方程振动的充分条件.
关键词 RICCATI变换 振动性 次线性中立项 正解
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一类具次线性中立项的二阶动力方程的振动性
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作者 赵春茹 《许昌学院学报》 2025年第2期6-11,共6页
在非正则条件下研究一类具有次线性中立项的二阶动力方程的振动性,利用时间轴上的微积分理论和广义黎卡提变换以及不等式技巧建立了一些新的振动准则,推广了已有文献中的结果,并给出应用实例加以验证.
关键词 振动性 二阶动力方程 次线性中立项 时间轴
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次线性g-期望的稳健表示及其应用研究
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作者 李敏 纪荣林 +1 位作者 钟文倩 周津名 《哈尔滨商业大学学报(自然科学版)》 2025年第4期474-479,共6页
在关于g-期望定义的基本假设条件下,基于倒向随机微分方程理论,深入探讨了生成元函数在刻画次线性g-期望的稳健表示中的核心作用.通过分析生成元函数的性质,在L^(p)(1<p≤∞)空间中建立了次线性g-期望的稳健表示定理.研究结果表明,... 在关于g-期望定义的基本假设条件下,基于倒向随机微分方程理论,深入探讨了生成元函数在刻画次线性g-期望的稳健表示中的核心作用.通过分析生成元函数的性质,在L^(p)(1<p≤∞)空间中建立了次线性g-期望的稳健表示定理.研究结果表明,在适当的可积性条件下,次线性g-期望可以表示为一类概率测度族上的上确界期望,这一发现本质性地拓展了非线性期望的表示框架.进一步地,获得了g-期望诱导的一致性风险度量的稳健表示模型.该模型满足单调性、平移不变性、次可加性和正齐次性等一致性公理,从而在金融风险管理中具有重要应用. 展开更多
关键词 倒向随机微分方程 G-期望 生成元 次线性g-期望 稳健表示 一致性风险度量
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基于BERTopic主题建模的“Assessing Writing”研究趋势演化分析
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作者 李锦焱 张丹 高慧敏 《河南科技大学学报(自然科学版)》 北大核心 2025年第4期97-104,M0008,共9页
通过深入挖掘期刊研究主题与预测学术发展趋势,研究人员能够更精准地把握学科方向,紧跟前沿动态。然而,期刊摘要作为短文本,其结构化特点、高维稀疏的向量表示、语义结构复杂性以及数据噪声等因素,对传统主题建模方法构成了严峻挑战。... 通过深入挖掘期刊研究主题与预测学术发展趋势,研究人员能够更精准地把握学科方向,紧跟前沿动态。然而,期刊摘要作为短文本,其结构化特点、高维稀疏的向量表示、语义结构复杂性以及数据噪声等因素,对传统主题建模方法构成了严峻挑战。针对这一问题,提出了一种基于BERTopic的主题演化分析模型。模型融合了预训练语言模型在语义表征方面的优势与层次化聚类算法的结构建模能力,同时重构词项加权策略,引入词频的次线性变换机制以优化传统词权计算方法,从而有效削弱高频词的干扰,突出对区分主题具有关键意义的词项,显著提升了模型的主题区分度和语义表征能力。以“Assessing Writing”期刊为研究对象,围绕不同时期写作评估领域的研究成果开展实证分析。通过系统梳理各阶段的研究主题与发展方向,挖掘其动态演化规律。实验结果表明,能够准确捕捉写作评估领域的研究热点变化,清晰揭示其发展脉络,在处理期刊摘要等短文本数据时展现出良好的实用性与有效性,为相关领域的学术研究和趋势预测提供了可靠的技术支撑。 展开更多
关键词 主题建模 BERTopic 语义结构 主题表征 次线性变换
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