期刊文献+
共找到1,307篇文章
< 1 2 66 >
每页显示 20 50 100
EXISTENCE AND NONEXISTENCE OF GLOBAL SOLUTIONS OF THE INITIAL-BOUNDARY VALUE PROBLEM FOR SOME DEGENERATE HYPERBOLIC EQUATION 被引量:1
1
作者 叶耀军 《Acta Mathematica Scientia》 SCIE CSCD 2005年第4期703-709,共7页
The author considers the global existence and global nonexistence of the initial-boundary value problem for some degenerate hyperbolic equation of the form utt- div(|△↓|^P-2 △↓u)=|u|^m u, (x,t)∈[0, +∞)... The author considers the global existence and global nonexistence of the initial-boundary value problem for some degenerate hyperbolic equation of the form utt- div(|△↓|^P-2 △↓u)=|u|^m u, (x,t)∈[0, +∞) ×Ω with p 〉 2 and m 〉 0. He deals with the global solutions by D.H.Sattinger's potential well ideas. At the same time, when the initial energy is positive, but appropriately bounded, the global nonexistence of solutions is verified by using the analysis method. 展开更多
关键词 Degenerate hyperbolic equations global existence and global nonexistence initial-boundary value problem
下载PDF
GLOBALLY SMOOTH SOLUTIONS TO CAUCHY PROBLEM OF A QUASILINEAR HYPERBOLIC SYSTEM ARISING IN BIOLOGY 被引量:2
2
作者 郑永树 《Acta Mathematica Scientia》 SCIE CSCD 2001年第4期460-468,共9页
This article considers Cauchy problem u(t) - (uv)(x) = 0, v(t) - u(x) = 0, u(x, 0) = u(0) (x) > 0, v(x, 0) = v(0)(x). A necessary and sufficient condition in guaranteeing that Cauchy problem admits a global C-1-sol... This article considers Cauchy problem u(t) - (uv)(x) = 0, v(t) - u(x) = 0, u(x, 0) = u(0) (x) > 0, v(x, 0) = v(0)(x). A necessary and sufficient condition in guaranteeing that Cauchy problem admits a global C-1-solution on t greater than or equal to 0 is obtained. 展开更多
关键词 nonlinear hyperbolic system Cauchy problem global C-1-solution
下载PDF
A GLOBALLY AND SUPERLINEARLY CONVERGENT TRUST REGION METHOD FOR LC^1 OPTIMIZATION PROBLEMS 被引量:1
3
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.
下载PDF
GLOBAL EXISTENCE OF SOLUTIONS OF CAUCHY PROBLEM FOR GENERALIZED BBM-BURGERS EQUATION 被引量:2
4
作者 耿世峰 陈国旺 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1007-1023,共17页
In this paper, the existence and the uniqueness of the local generalized solution and the local classical solution of the Cauchy problem for the generalized BBM-Burgers equationare proved. The existence and the unique... In this paper, the existence and the uniqueness of the local generalized solution and the local classical solution of the Cauchy problem for the generalized BBM-Burgers equationare proved. The existence and the uniqueness of the global generalized solution and the global classical solution for the Cauchy problem of equation (1) are proved when n = 3, 2, 1. Moreover, the decay property of the solution is discussed. 展开更多
关键词 generalized BBM-Burgers equation Cauchy problem global solution decayproperty of solution
下载PDF
GLOBAL EXISTENCE OF WEAKLY DISCONTINUOUS SOLUTIONS TO A KIND OF MIXED INITIAL-BOUNDARY VALUE PROBLEM FOR QUASILINEAR HYPERBOLIC SYSTEMS 被引量:2
5
作者 Guo Fei School of Mathematical Sciences, Fudan University, Shanghai 200433, China Department of Mathematics, Qufu Normal University, Shandong, 273165, China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第2期181-200,共20页
In this paper, the mixed initial-boundary value problem for general first order quasi- linear hyperbolic systems with nonlinear boundary conditions in the domain D = {(t, x) | t ≥ 0, x ≥0} is considered. A suffic... In this paper, the mixed initial-boundary value problem for general first order quasi- linear hyperbolic systems with nonlinear boundary conditions in the domain D = {(t, x) | t ≥ 0, x ≥0} is considered. A sufficient condition to guarantee the existence and uniqueness of global weakly discontinuous solution is given. 展开更多
关键词 quasilinear hyperbolic system mixed initial-boundary value problem global weakly discontinu-ous solution weak linear degeneracy
下载PDF
Integral Global Minimization of Constrained Problems with Discontinuous Penalty Functions 被引量:1
6
作者 吴斌 崔洪泉 郑权 《Journal of Shanghai University(English Edition)》 CAS 2005年第5期385-390,共6页
A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained ... A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained and penalized minimization problem were investigated. A nonsequential algorithm was proposed. Numerical examples were given to illustrate the effectiveness of the algorithm. 展开更多
关键词 integral global minimization constrained minimization problems discontinuous penalty functions.
下载PDF
GLOBAL SOLUTION TO THE CAUCHY PROBLEM ON A UNIVERSE FIREWORKS MODEL
7
作者 姜正禄 田红炯 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期281-288,共8页
We prove existence and uniqueness of the global solution to the Cauchy problem on a universe fireworks model with finite total mass at the initial state when the ratio of the mass surviving the explosion, the probabil... We prove existence and uniqueness of the global solution to the Cauchy problem on a universe fireworks model with finite total mass at the initial state when the ratio of the mass surviving the explosion, the probability of the explosion of fragments and the probability function of the velocity change of a surviving particle satisfy the corresponding physical conditions. Although the nonrelativistic Boltzmann-like equation modeling the universe fireworks is mathematically easy, this article leads rather theoretically to an understanding of how to construct contractive mappings in a Banach space for the proof of the existence and uniqueness of the solution by means of methods taken from the famous work by DiPerna & Lions about the Boltzmann equation. We also show both the regularity and the time-asymptotic behavior of solution to the Cauchy problem. 展开更多
关键词 Cauchy problem global solution universe fireworks
下载PDF
A NECESSARY AND SUFFICIENT CONDITION FOR GLOBAL EXISTENCE OF CLASSICAL SOLUTIONS TO CAUCHY PROBLEM OF QUASILINEAR HYPERBOLIC SYSTEMS IN DIAGONAL FORM
8
作者 郑永树 刘法贵 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期571-576,共6页
This article considers Cauchy problem for quasilinear hyperbolic systems in diagonal form. A necessary and sufficient condition in guaranteeing that Cauchy problem admits a unique global classical solution on t ≥ 0 i... This article considers Cauchy problem for quasilinear hyperbolic systems in diagonal form. A necessary and sufficient condition in guaranteeing that Cauchy problem admits a unique global classical solution on t ≥ 0 is obtained, and a sharp estimate of the life span for the classical solution is given. 展开更多
关键词 Cauchy problem global classical solution BLOW-UP life s
下载PDF
A GLOBAL LINEAR AND LOCAL QUADRATIC SINGLE-STEP NONINTERIOR CONTINUATION METHOD FOR MONOTONE SEMIDEFINITE COMPLEMENTARITY PROBLEMS 被引量:1
9
作者 张立平 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期243-253,共11页
A noninterior continuation method is proposed for semidefinite complementarity problem (SDCP). This method improves the noninterior continuation methods recently developed for SDCP by Chen and Tseng. The main proper... A noninterior continuation method is proposed for semidefinite complementarity problem (SDCP). This method improves the noninterior continuation methods recently developed for SDCP by Chen and Tseng. The main properties of our method are: (i) it is well d.efined for the monotones SDCP; (ii) it has to solve just one linear system of equations at each step; (iii) it is shown to be both globally linearly convergent and locally quadratically convergent under suitable assumptions. 展开更多
关键词 Semidefinite complementarity problem noninterior continuation method global convergence local quadratic convergence
下载PDF
EXISTENCE AND NONEXISTENCE OF GLOBAL CONTINUOUS SOLUTIONS TO RIEMANN PROBLEM FOR DAMPED P-SYSTEM
10
作者 林龙威 杨彤 《Acta Mathematica Scientia》 SCIE CSCD 1993年第1期1-12,共12页
In this paper, we extend the result in [16] to general p(v). We prove that, under condition (M), when P greater-than-or-equal-to 3/2, where P=pp triple overdot/p2, there exists a unique global continuous solution to t... In this paper, we extend the result in [16] to general p(v). We prove that, under condition (M), when P greater-than-or-equal-to 3/2, where P=pp triple overdot/p2, there exists a unique global continuous solution to the Riemann problem (E), (R), whose structure is similar to the local solution. When 1 < P* less-than-or-equal-to P* < 5/4, or P* = P* = 5/4, or 5 < P* less-than-or-equal-to P* < 3/2 where P*-inf/v P and P* = sup/v P for all v under consideration, if at least one of the initial centered rarefaction waves is sufficiently strong, then the solution must be breakdown in a finite time. 展开更多
关键词 EXISTENCE AND NONEXISTENCE OF global CONTINUOUS SOLUTIONS TO RIEMANN problem FOR DAMPED P-SYSTEM
下载PDF
EXISTENCE RESULTS FOR GLOBALLY EFFICIENT SOLUTIONS OF VECTOR EQUILIBRIUM PROBLEMS VIA A GENERALIZED KKM PRINCIPLE 被引量:2
11
作者 Adela CAPATA 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期463-476,共14页
The aim of this article is to present new existence results for globally efficient solutions of a strong vector equilibrium problem given by a sum of two functions via a generalized KKM principle, and to establish the... The aim of this article is to present new existence results for globally efficient solutions of a strong vector equilibrium problem given by a sum of two functions via a generalized KKM principle, and to establish the connectedness of the solutions set. 展开更多
关键词 KKM principle equilibrium problems given by a sum globally efficient solution near C-subconvexlikeness
下载PDF
GLOBAL OPTIMIZATION OF PUMP CONFIGURATION PROBLEM USING EXTENDED CROWDING GENETIC ALGORITHM 被引量:3
12
作者 ZhangGuijun WuTihua YeRong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期247-252,共6页
An extended crowding genetic algorithm (ECGA) is introduced for solvingoptimal pump configuration problem, which was presented by T. Westerlund in 1994. This problem hasbeen found to be non-convex, and the objective f... An extended crowding genetic algorithm (ECGA) is introduced for solvingoptimal pump configuration problem, which was presented by T. Westerlund in 1994. This problem hasbeen found to be non-convex, and the objective function contained several local optima and globaloptimality could not be ensured by all the traditional MINLP optimization method. The concepts ofspecies conserving and composite encoding are introduced to crowding genetic algorithm (CGA) formaintain the diversity of population more effectively and coping with the continuous and/or discretevariables in MINLP problem. The solution of three-levels pump configuration got from DICOPT++software (OA algorithm) is also given. By comparing with the solutions obtained from DICOPT++, ECPmethod, and MIN-MIN method, the ECGA algorithm proved to be very effective in finding the globaloptimal solution of multi-levels pump configuration via using the problem-specific information. 展开更多
关键词 Pump configuration problem Extended crowding genetic algorithm Speciesconserving Composite encoding global optimization
下载PDF
GLOBAL LINEAR AND QUADRATIC ONE-STEP SMOOTHING NEWTON METHOD FOR VERTICAL LINEAR COMPLEMENTARITY PROBLEMS
13
作者 张立平 高自友 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第6期738-746,F003,共10页
A one_step smoothing Newton method is proposed for solving the vertical linear complementarity problem based on the so_called aggregation function. The proposed algorithm has the following good features: (ⅰ) It solve... A one_step smoothing Newton method is proposed for solving the vertical linear complementarity problem based on the so_called aggregation function. The proposed algorithm has the following good features: (ⅰ) It solves only one linear system of equations and does only one line search at each iteration; (ⅱ) It is well_defined for the vertical linear complementarity problem with vertical block P 0 matrix and any accumulation point of iteration sequence is its solution.Moreover, the iteration sequence is bounded for the vertical linear complementarity problem with vertical block P 0+R 0 matrix; (ⅲ) It has both global linear and local quadratic convergence without strict complementarity. Many existing smoothing Newton methods do not have the property (ⅲ). 展开更多
关键词 vertical linear complementarity problems smoothing Newton method global linear convergence quadratic convergence
下载PDF
Effect of Weight Function in Nonlinear Part on Global Solvability of Cauchy Problem for Semi-Linear Hyperbolic Equations
14
作者 Akbar B. Aliev Anar A. Kazimov 《International Journal of Modern Nonlinear Theory and Application》 2013年第1期102-106,共5页
In this paper, we investigate the effect of weight function in the nonlinear part on global solvability of the Cauchy problem for a class of semi-linear hyperbolic equations with damping.
关键词 CAUCHY problem Wave EQUATION global SOLVABILITY Weight Function SEMI-LINEAR Hyperbolic EQUATION
下载PDF
Global 1 Estimation of the Cauchy Problem Solutions to the Navier-Stokes Equation
15
作者 Asset Durmagambetov Leyla Fazilova 《Applied Mathematics》 2014年第13期1903-1912,共10页
The analytic properties of the scattering amplitude are discussed, and a representation of the potential is obtained using the scattering amplitude. A uniform time estimation of the Cauchy problem solution for the Nav... The analytic properties of the scattering amplitude are discussed, and a representation of the potential is obtained using the scattering amplitude. A uniform time estimation of the Cauchy problem solution for the Navier-Stokes equations is provided. The paper also describes the time blowup of classical solutions for the Navier-Stokes equations by the smoothness assumption. 展开更多
关键词 Schrodinger's Equation Potential Scattering Amplitude Cauchy problem Navier-Stokes Equations Fourier Transform global Solvability and Uniqueness of the Cauchy problem Loss of Smoothness
下载PDF
Global Optimization for Solving Linear Non-Quadratic Optimal Control Problems
16
作者 Jinghao Zhu 《Journal of Applied Mathematics and Physics》 2016年第10期1859-1869,共11页
This paper presents a global optimization approach to solving linear non-quadratic optimal control problems. The main work is to construct a differential flow for finding a global minimizer of the Hamiltonian function... This paper presents a global optimization approach to solving linear non-quadratic optimal control problems. The main work is to construct a differential flow for finding a global minimizer of the Hamiltonian function over a Euclid space. With the Pontryagin principle, the optimal control is characterized by a function of the adjoint variable and is obtained by solving a Hamiltonian differential boundary value problem. For computing an optimal control, an algorithm for numerical practice is given with the description of an example. 展开更多
关键词 Linear Non-Quadratic Optimal Control Pontryagin Principle global Optimization Hamiltonian Differential Boundary Value problem
下载PDF
Global Weak Solutions of Initial Boundary Value Problem for Boltzmann-Poisson System with Absorbing Boundary
17
作者 崔国忠 张志平 江成顺 《Northeastern Mathematical Journal》 CSCD 2002年第1期33-43,共11页
This paper deals with the initial boundary value problem for the Boltzmann-Poisson system, which arises in semiconductor physics, with absorbing boundary. The global existence of weak solutions is proved by using the ... This paper deals with the initial boundary value problem for the Boltzmann-Poisson system, which arises in semiconductor physics, with absorbing boundary. The global existence of weak solutions is proved by using the stability of velocity averages and the compactness results on L1-theory under weaker conditons on initial boundary values. 展开更多
关键词 global weak solution Boltzmann-Poisson system initial boundary value problem
下载PDF
带隐藏约束昂贵黑箱问题的自适应代理优化方法
18
作者 白富生 兰秘 《运筹学学报(中英文)》 CSCD 北大核心 2024年第1期89-100,共12页
针对带隐藏约束的昂贵黑箱全局优化问题,提出采用自适应转换搜索策略的代理优化方法。在转换搜索子步中采用与已估值点个数相关的标准差在当前最优点附近通过随机扰动生成候选点,以更好地平衡局部搜索和全局搜索。为更好地近似真实黑箱... 针对带隐藏约束的昂贵黑箱全局优化问题,提出采用自适应转换搜索策略的代理优化方法。在转换搜索子步中采用与已估值点个数相关的标准差在当前最优点附近通过随机扰动生成候选点,以更好地平衡局部搜索和全局搜索。为更好地近似真实黑箱目标函数,采用了自适应组合目标代理模型。在50个测试问题上进行了数值实验,计算结果说明了所提算法的有效性。 展开更多
关键词 昂贵黑箱问题 全局优化 隐藏约束 代理优化
下载PDF
一个含抑制剂作用的肿瘤生长模型整体解的存在唯一性
19
作者 宋灵宇 盖梦琳 朱妍红 《西北师范大学学报(自然科学版)》 2024年第1期14-19,共6页
研究一个营养物和抑制物同时存在的非线性血管化肿瘤生长模型.首先运用边界固定法将自由边界问题转化为固定边界上的非线性初边值问题,其次运用抛物型方程的L^(p)理论和Banach不动点定理构造压缩映射,证明该问题局部解的存在唯一性,最... 研究一个营养物和抑制物同时存在的非线性血管化肿瘤生长模型.首先运用边界固定法将自由边界问题转化为固定边界上的非线性初边值问题,其次运用抛物型方程的L^(p)理论和Banach不动点定理构造压缩映射,证明该问题局部解的存在唯一性,最后利用变换函数与其原始函数之间的关系,用延拓方法得到整体解的存在唯一性. 展开更多
关键词 肿瘤生长模型 自由边界问题 整体解 存在性 唯一性
下载PDF
工业智能化与全球碳减排
20
作者 杨春蕾 佟继英 《经济经纬》 北大核心 2024年第1期110-119,共10页
基于1993—2019年51个国家的平衡面板数据,运用双重固定效应模型、中介效应模型和门槛效应模型,分析了工业智能化对全球碳减排的影响和内在机理。研究发现:工业智能化能够显著推动全球碳减排,经过一系列稳健性检验后该结论依然成立。中... 基于1993—2019年51个国家的平衡面板数据,运用双重固定效应模型、中介效应模型和门槛效应模型,分析了工业智能化对全球碳减排的影响和内在机理。研究发现:工业智能化能够显著推动全球碳减排,经过一系列稳健性检验后该结论依然成立。中介效应回归结果表明,工业智能化可以通过制造业高端化和产业结构升级渠道推动全球碳减排。门槛效应回归结果表明,全球碳减排不仅受工业智能化自身发展水平的动态影响,工业集聚度在其中也发挥着调节作用。进一步研究发现,工业智能化能够更大幅度降低全球富裕国家和富裕群体的人均碳足迹,有助于缓解全球碳排放的不平等。因此,应当推动人工智能技术在工业领域的广泛应用,通过跟踪碳足迹评估政策的实际环境影响,推动工业智能化与碳减排领域的国际合作。 展开更多
关键词 工业智能化 气候问题 全球碳减排 碳足迹 包容性发展
下载PDF
上一页 1 2 66 下一页 到第
使用帮助 返回顶部