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SELF-SIMILAR SOLUTIONS AND BLOW-UP PHENOMENA FOR A TWO-COMPONENT SHALLOW WATER SYSTEM 被引量:2
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作者 周寿明 穆春来 王良晨 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期821-829,共9页
In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equat... In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equations is established. Some sufficient conditions for blow-up of the solutions in finite time are given. Moreover, by separation method, the self-similar solutions for the nonlinear shallow water equations are obtained, and which local or global behavior can be determined by the corresponding Emden equation. 展开更多
关键词 Self-similar solutions blow-up phenomena two-component shallow water system
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Blow-Up Phenomena for a Class of Parabolic Systems with Time Dependent Coefficients 被引量:15
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作者 Lawrence E. Payne Gérard A. Philippin 《Applied Mathematics》 2012年第4期325-330,共6页
Blow-up phenomena for solutions of some nonlinear parabolic systems with time dependent coefficients are investigated. Both lower and upper bounds for the blow-up time are derived when blow-up occurs.
关键词 PARABOLIC Systems blow-up SOBOLEV Type INEQUALITY
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GLOBAL EXISTENCE AND BLOW-UP PHENOMENA OF CLASSICAL SOLUTIONS FOR THE SYSTEM OF COMPRESSIBLE ADIABATIC FLOW THROUGH POROUS MEDIA 被引量:2
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作者 刘法贵 孔德兴 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期703-713,共11页
By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result o... By means of maximum principle for nonlinear hyperbolic systems, the results given by HSIAO Ling and D. Serre was improved for Cauchy problem of compressible adiabatic flow through porous media, and a complete result on the global existence and the blow-up phenomena of classical solutions of these systems. These results show that the dissipation is strong enough to preserve the smoothness of ‘small ’ solution. 展开更多
关键词 porous media compressible adiabatic flow system of equations classical solution global existence blow-up
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On the Blow-up Phenomena of Cauchy Problem for the Camassa-Holm Equation
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作者 LIU Yongqin WANG Weike 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第3期451-455,共5页
We focus on the blow-up phenomena of Cauchy problem for the Camassa-Holm equation. Blow-up can occur only in the form of wave-breaking, i.e. the solution is bounded but its slope becomes unbounded in finite time. We p... We focus on the blow-up phenomena of Cauchy problem for the Camassa-Holm equation. Blow-up can occur only in the form of wave-breaking, i.e. the solution is bounded but its slope becomes unbounded in finite time. We proved that there is such a point that its slope becomes infinite exactly at breaking time. We also gave the precise blow-up rate and the blow-up set. 展开更多
关键词 WAVE-BREAKING blow-up rate blow-up set
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Multi-layer phenomena in petawatt laser-driven acceleration of heavy ions
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作者 苏琬晴 曹喜光 +2 位作者 马春旺 王玉廷 张国强 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期70-76,共7页
Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(Smilei) is employed to simulate the entire process of Station of Extreme Light(SEL) 100 PW l... Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(Smilei) is employed to simulate the entire process of Station of Extreme Light(SEL) 100 PW laser-accelerated heavy particles using different nanoscale short targets with a thickness of 100 nm Cr, Fe, Ag, Ta, Au, Pb, Th and U, as well as 200 nm thick Al and Ca. An obvious stratification is observed in the simulation. The layering phenomenon is a hybrid acceleration mechanism reflecting target normal sheath acceleration and radiation pressure acceleration, and this phenomenon is understood from the simulated energy spectrum,ionization and spatial electric field distribution. According to the stratification, it is suggested that high-quality heavy-ion beams could be expected for fusion reactions to synthesize superheavy nuclei. Two plasma clusters in the stratification are observed simultaneously, which suggest new techniques for plasma experiments as well as thinner metal targets in the precision machining process. 展开更多
关键词 petawatt laser-plasma interaction laser-driven heavy-ion accelerator for synthesizing superheavy nuclei PARTICLE-IN-CELL multi-layer phenomena target fabrication
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BLOW-UP CONDITIONS FOR A SEMILINEAR PARABOLIC SYSTEM ON LOCALLY FINITE GRAPHS
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作者 吴艺婷 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期609-631,共23页
In this paper, we investigate a blow-up phenomenon for a semilinear parabolic system on locally finite graphs. Under some appropriate assumptions on the curvature condition CDE’(n,0), the polynomial volume growth of ... In this paper, we investigate a blow-up phenomenon for a semilinear parabolic system on locally finite graphs. Under some appropriate assumptions on the curvature condition CDE’(n,0), the polynomial volume growth of degree m, the initial values, and the exponents in absorption terms, we prove that every non-negative solution of the semilinear parabolic system blows up in a finite time. Our current work extends the results achieved by Lin and Wu (Calc Var Partial Differ Equ, 2017, 56: Art 102) and Wu (Rev R Acad Cien Serie A Mat, 2021, 115: Art 133). 展开更多
关键词 semilinear parabolic system on graphs blow-up heat kernel estimate on graphs
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Blow-up phenomena of the vector nonlinear Schrdinger equations with magnetic fields 被引量:3
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作者 GAN ZaiHui GUO BoLing 《Science China Mathematics》 SCIE 2011年第10期2111-2122,共12页
This paper is concerned with the finite time blow-up phenomena for the vector nonlinear Schrdinger equations with a magnetic field which describe the spontaneous generation of a magnetic field in a cold plasma in the ... This paper is concerned with the finite time blow-up phenomena for the vector nonlinear Schrdinger equations with a magnetic field which describe the spontaneous generation of a magnetic field in a cold plasma in the subsonic limit. After obtaining some a priori estimates,we prove under certain natural conditions that the solutions to the Cauchy problem of the vector nonlinear Schrdinger equations in two and three spatial dimensions blow up in a finite time. Assuming that a solution to the aforementioned vector nonlinear Schrdinger equations is radially symmetric with respect to spatial variables x,we show that if the initial energy is non-positive,then the solution blows up in three dimensions in a finite time. 展开更多
关键词 薛定谔方程 非线性 场矢量 CAUCHY问题 爆破 低温等离子体 有限时间 BLOW
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Elucidating Ion Transport Phenomena in Sulfide/Polymer Composite Electrolytes for Practical Solid-State Batteries 被引量:2
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作者 Kyeong‑Seok Oh Ji Eun Lee +7 位作者 Yong‑Hyeok Lee Yi‑Su Jeong Imanuel Kristanto Hong‑Seok Min Sang‑Mo Kim Young Jun Hong Sang Kyu Kwak Sang‑Young Lee 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期416-432,共17页
Despite the enormous interest in inorganic/polymer composite solid-state electrolytes(CSEs)for solid-state batteries(SSBs),the underlying ion transport phenomena in CSEs have not yet been elucidated.Here,we address th... Despite the enormous interest in inorganic/polymer composite solid-state electrolytes(CSEs)for solid-state batteries(SSBs),the underlying ion transport phenomena in CSEs have not yet been elucidated.Here,we address this issue by formulating a mechanistic understanding of bi-percolating ion channels formation and ion conduction across inorganic-polymer electrolyte interfaces in CSEs.A model CSE is composed of argyrodite-type Li_6PS_5Cl(LPSCl)and gel polymer electrolyte(GPE,including Li~+-glyme complex as an ion-conducting medium).The percolation threshold of the LPSCl phase in the CSE strongly depends on the elasticity of the GPE phase.Additionally,manipulating the solvation/desolvation behavior of the Li~+-glyme complex in the GPE facilitates ion conduction across the LPSCl-GPE interface.The resulting scalable CSE(area=8×6(cm×cm),thickness~40μm)can be assembled with a high-mass-loading LiNi_(0.7)Co_(0.15)Mn_(0.15)O_(2)cathode(areal-mass-loading=39 mg cm~(-2))and a graphite anode(negative(N)/positive(P)capacity ratio=1.1)in order to fabricate an SSB full cell with bi-cell configuration.Under this constrained cell condition,the SSB full cell exhibits high volumetric energy density(480 Wh L_(cell)~(-1))and stable cyclability at 25℃,far exceeding the values reported by previous CSE-based SSBs. 展开更多
关键词 Solid-state batteries Composite solid-state electrolytes Ion transport phenomena Bi-percolating ion channels Interfacial resistance
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Remarks on Blow-Up Phenomena in p-Laplacian Heat Equation with Inhomogeneous Nonlinearity
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作者 ALZAHRANI Eadah Ahma MAJDOUB Mohamed 《Journal of Partial Differential Equations》 CSCD 2021年第1期42-50,共9页
We investigate the p-Laplace heat equation ut-△_(p)u=ζ(t)f(u)in a bounded smooth domain.Using differential-inequality arguments,we prove blow-up results under suitable conditions onζ,f,and the initial datum u_(0).W... We investigate the p-Laplace heat equation ut-△_(p)u=ζ(t)f(u)in a bounded smooth domain.Using differential-inequality arguments,we prove blow-up results under suitable conditions onζ,f,and the initial datum u_(0).We also give an upper bound for the blow-up time in each case. 展开更多
关键词 Parabolic problems p-Laplacian equation blow-up positive initial energy
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Blow-Up Phenomena for Some Pseudo-Parabolic Equations with Nonlocal Term
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作者 Gongwei Liu Shuying Tian 《Analysis in Theory and Applications》 CSCD 2022年第4期451-466,共16页
We investigate the initial boundary value problem of some semilinear pseudo-parabolic equations with Newtonian nonlocal term.We establish a lower bound for the blow-up time if blow-up does occur.Also both the upper bo... We investigate the initial boundary value problem of some semilinear pseudo-parabolic equations with Newtonian nonlocal term.We establish a lower bound for the blow-up time if blow-up does occur.Also both the upper bound for T and blow up rate of the solution are given when J(u 0)<0.Moreover,we establish the blow up result for arbitrary initial energy and the upper bound for T.As a product,we refine the lifespan when J(u 0)<0. 展开更多
关键词 Nonlocal pseudo-parabolic equations blow-up upper bound lower bound.
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BLOW-UP SOLUTIONS OF TWO-COUPLED NONLINEAR SCHR?DINGER EQUATIONS IN THE RADIAL CASE
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作者 白欠欠 李晓光 张莉 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1852-1864,共13页
We consider the blow-up solutions to the following coupled nonlinear Schr¨odinger equations{iu_(t)+Δu+(|u|^(2p)+|u|^(p−1)|v|^(p+1))u=0,iv_(t)+Δv+(|v|^(2p)+|v|^(p−1)|u|^(p+1))v=0,u(0,x)=u0(x),v(0,x)=v0(x),x 2 R ... We consider the blow-up solutions to the following coupled nonlinear Schr¨odinger equations{iu_(t)+Δu+(|u|^(2p)+|u|^(p−1)|v|^(p+1))u=0,iv_(t)+Δv+(|v|^(2p)+|v|^(p−1)|u|^(p+1))v=0,u(0,x)=u0(x),v(0,x)=v0(x),x 2 R N,t0.On the basis of the conservation of mass and energy,we establish two sufficient conditions to obtain the existence of a blow-up for radially symmetric solutions.These results improve the blow-up result of Li and Wu[10]by dropping the hypothesis of finite variance((|x|u_(0),|x|v_(0))∈ L^(2)(R^(N))×L^(2)(R^(N))). 展开更多
关键词 SchrOdinger equations radial symmetry blow-up virial identity
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SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
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作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-Laplacian equation boundary blow-up sub-supersolution method EXISTENCE nonexistence and estimates sufficient and necessary conditions
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纳米材料中的界面现象
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作者 阮文娟 李悦 郭东升 《大学化学》 CAS 2024年第1期80-86,共7页
在课程教学中融入科学前沿实例不仅可以阐明所学基本原理的实际意义,还可以为基本原理的灵活应用提供范例,启发学生独立思考能力。界面化学是物理化学课程中的重要学习内容,但由于在常规尺度的多相体系中界面现象并不显著,学生对该部分... 在课程教学中融入科学前沿实例不仅可以阐明所学基本原理的实际意义,还可以为基本原理的灵活应用提供范例,启发学生独立思考能力。界面化学是物理化学课程中的重要学习内容,但由于在常规尺度的多相体系中界面现象并不显著,学生对该部分知识常有忽视。近年来纳米材料已成为国内外研究的热点。纳米材料由于其高界面分子比例而表现出更为显著的界面现象。将界面化学的基本原理应用于纳米材料的研究中,已取得了一系列令人瞩目的成果。本文首先对附加压力、接触角等相关界面现象的基本原理进行梳理,然后分别介绍根据这些基本原理所发展出的分子马达、光控微流控器件、液体门控技术以及超疏水表面四项科技突破。 展开更多
关键词 界面现象 分子马达 光控微流控器件 液体门控技术 超疏水表面
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医药院校物理化学课程思政元素的挖掘
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作者 苑娟 潘攀 《药学教育》 2024年第2期28-31,共4页
物理化学是医药院校药学专业的重要专业基础课程,蕴含丰富的思政元素。为深入贯彻“以德育人”的教育理念,高校应充分借助课堂教学平台,深入挖掘物理化学课程中所蕴含的思政元素。文章对物理化学“表面现象”章节的思政元素进行探讨,阐... 物理化学是医药院校药学专业的重要专业基础课程,蕴含丰富的思政元素。为深入贯彻“以德育人”的教育理念,高校应充分借助课堂教学平台,深入挖掘物理化学课程中所蕴含的思政元素。文章对物理化学“表面现象”章节的思政元素进行探讨,阐述思政元素与相关内容融合的切入点。在教学过程中融入思政元素,既培养学生的学习兴趣,又提升了学生的思想道德修养。 展开更多
关键词 课程思政 物理化学 表面现象
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大语言模型时代的开源知识生产:机遇、挑战与未来
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作者 甘莅豪 《华东师范大学学报(哲学社会科学版)》 北大核心 2024年第2期31-41,179,共12页
随着大语言模型的崛起,开源知识生产领域迎来了新的变革。大语言模型对开源知识生产的积极影响及其潜在挑战并存。一方面,大语言模型通过适应开源社区的坎宁安定律、提供全天候的新人知识培训支持,以及通过领域化构建策略来修正知识生... 随着大语言模型的崛起,开源知识生产领域迎来了新的变革。大语言模型对开源知识生产的积极影响及其潜在挑战并存。一方面,大语言模型通过适应开源社区的坎宁安定律、提供全天候的新人知识培训支持,以及通过领域化构建策略来修正知识生产的系统性偏差,显著提升了开源知识的生成与传播效率;另一方面,大语言模型带来的幻觉现象、版权风险、数字剥削问题以及“死亡互联网”趋势的加剧,对开源知识的核查、合法性、价值观以及生态环境构成了严重威胁。基于此,未来应强化人类认知体验在引导大语言模型技术发展中的核心作用,并通过实践不断探索解决方案,以期实现大语言模型知识生产与开源知识生产的和谐共生及共同进步。 展开更多
关键词 大语言模型 开源知识生产 系统性偏差 幻觉现象 数字剥削 维基百科
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基于混合粒子群算法的波浪能发电集群优化方法
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作者 朱永强 朱显浩 《可再生能源》 CAS CSCD 北大核心 2024年第2期259-266,共8页
对波浪能发电集群的优化控制有助于波浪能的有效利用,为此文章提出了基于混合粒子群算法的波浪能发电集群优化方法。以直驱式发电装置为研究对象,探讨其构成发电集群短期尺度下稳定状态的数学模型,由简至繁依次考虑波浪动态压力、装置... 对波浪能发电集群的优化控制有助于波浪能的有效利用,为此文章提出了基于混合粒子群算法的波浪能发电集群优化方法。以直驱式发电装置为研究对象,探讨其构成发电集群短期尺度下稳定状态的数学模型,由简至繁依次考虑波浪动态压力、装置间辐射影响和遮挡效应,以便更准确地模拟一定密集度的波浪能发电装置部署下的实际效果。以集群功率最大化为优化目标,根据装置运动和海域能量约束,提出混合粒子群算法求解集群的最优参数,在传统算法基础上设定自适应惯性权重并加入交叉和变异操作,以应对复杂集群方程解空间的多峰性问题。算例结果验证了所述集群优化方法的有效性,求解质量良好;同时表明波浪能发电集群规模越大,装置之间的辐射影响越复杂,遮挡效应越明显。 展开更多
关键词 波浪能发电集群 辐射影响 遮挡效应 集群优化 混合粒子群算法
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社交媒体时代青年“偶像文化”透视与教育引导
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作者 李慧静 邵静云 《文化创新比较研究》 2024年第10期57-61,共5页
文章首先明确“偶像文化”相关概念内涵,从理论上解析网络青年亚文化、“偶像文化”。其次,对“偶像文化”进行深层透析,从现实呈现上说明“偶像文化”“是何”的问题。再次,运用多学科综合分析,从教育学、心理学、社会学、新闻传播学... 文章首先明确“偶像文化”相关概念内涵,从理论上解析网络青年亚文化、“偶像文化”。其次,对“偶像文化”进行深层透析,从现实呈现上说明“偶像文化”“是何”的问题。再次,运用多学科综合分析,从教育学、心理学、社会学、新闻传播学等学科探讨“粉丝”群体的行为表现与心理机制,说明“何以”的问题。从次,探究“偶像文化”的影响,说明“有何”影响的问题。最后,针对粉丝行为的“失范”,提出有效的应对措施,回答“如何”应对“偶像文化”影响的问题,切实回应引导“偶像文化”有序发展及青年价值观培塑的时代要求和现实诉求。 展开更多
关键词 网络青年亚文化 社交媒体时代 “偶像文化” 心理机制 “失范”现象 教育引导
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具非线性边界条件的拟线性抛物型方程解的Blow-up 被引量:10
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作者 张海亮 贾新春 《数学杂志》 CSCD 北大核心 2002年第2期195-198,共4页
本文考虑一类具非线性边界条件的拟线性抛物方程初边值问题解的整体性态 .通过构造与解有关的适当积分 ,利用“凸性方法”及非线性抛物型方程的极大值原理 ,证明了在某些条件下 ,问题的光滑解u(x ,t)只能在一个有界区间 (0 ,T0 )中存在 ... 本文考虑一类具非线性边界条件的拟线性抛物方程初边值问题解的整体性态 .通过构造与解有关的适当积分 ,利用“凸性方法”及非线性抛物型方程的极大值原理 ,证明了在某些条件下 ,问题的光滑解u(x ,t)只能在一个有界区间 (0 ,T0 )中存在 ,即有 :limt→T-0sup‖u(· ,t)‖ ∞ =+∞ . 展开更多
关键词 拟线性抛物型方程 非线性边界条件 凸性方法 blow-up 最大值原理
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一类推广了的非线性Schrdinger方程初边值解的blow-up 被引量:2
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作者 赵军生 郭巧栋 +1 位作者 杨海鸥 徐润章 《黑龙江大学自然科学学报》 CAS 北大核心 2008年第2期170-172,177,共4页
研究一类推广了的非线性Schrdinger方程的初边值问题ut-iΔu=f(u,Dxu,D2xu)+Δg(u),u(x,0)=u0(x),uΩ=0.作为ut-iΔu=f(u,Dxu,D2xu)及ut-iΔu=-Δg(u)的推广,用特征函数法,在某些条件下,证明了此问题整体解的不存在性与有限时间blow-up.
关键词 非线性Schriōdinger方程 特征函数法 初边值 blow-up
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奇异半线性发展方程组解的Blow-up问题 被引量:2
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作者 郭高荣 平翠萍 杨凤藻 《昆明理工大学学报(理工版)》 2006年第6期122-124,共3页
讨论奇异半线性发展方程组解的B low-up问题时,通常先对解进行估计,然后讨论在一定条件下解的B low-up.论文继续用这种方法讨论奇异半线性发展方程组解的B low-up问题,得到一定条件下解会B low-up.
关键词 奇异 半线性 blow-up问题
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