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1.
尖峰孤立子是一个非线性色散方程的尖峰孤立波解,是浅水波理论中的一个模型.本文通过构造一个泛函和守恒律来证明DGH方程的尖峰孤立子在H~1中的轨道稳定性.该稳定性定理表明,如果一个波在开始时与尖锋孤立子接近,则在之后的任何时间仍然与它接近.  相似文献   

2.
组合KdV方程在物理学的许多领域都有应用,例如等离子体磁流波、离子声波等。粒子在传输过程中需要刻画其稳定性。本文主要通过平移变换,将研究带有非零渐近值的孤立波解的轨道稳定性,转化为研究具有零渐进值孤立波解的轨道稳定性,给出了稳定性的判定定理,应用Grillakis-Shatah-Strauss提出的轨道稳定性理论与谱分析理论得到了组合KdV方程的几种孤立波解的轨道稳定性结论。  相似文献   

3.
广义Camassa-Holm方程孤立波解的轨道稳定性   总被引:2,自引:0,他引:2  
研究广义Camassa-Holm方程孤立波解的轨道稳定性问题.基于Grillakis、Statah、Strauss建立的关于非线性哈密顿系统孤立波轨道稳定的抽象理论框架,通过细致的谱分析和计算,证明了该方程的一族显示不光滑孤立波是轨道稳定的.  相似文献   

4.
奇异扰动MKdV-KS方程孤立波解的存在性   总被引:1,自引:1,他引:1  
孤立波现象是很活跃的一个研究领域,但带有小扰动的方程的孤立波目前研究还较少.讨论奇异扰动MKdV—KS方程孤立波解的存在性,利用孤立波与同宿轨之间的关系,通过变量替换,将MKdV—KS方程约化为带快-慢变量的常微分方程组,利用奇异扰动定性理论,找出退化慢子系统的同宿轨,证明扰动之后的方程组也存在同宿轨,从而证明MKdV-KS方程仍有孤立波解.  相似文献   

5.
陀螺相关非孤立系统的研究工作,不仅是在理论上而且在航空和航天科学的应用上,都具有重要的作用。这是一个比较困难的问题,所以至今还没有完全解决。 本文首先继续[6],通过两个引理和两个定理的证明,提供了解决非孤立陀螺系统不稳定性问题的一种判据。作为例子,利用我们的定理分析解决了“二重自旋卫星”姿态稳定性问题中其他两个问题[9]。 本文第二部分,利用关于部分变量的运动稳定性的定理[10],我们来研究另外一类非孤立陀螺系统的运动稳定性问题。最后,我们举例,通过分析一个卫星试验的力学模型,来说明利用上述方法在实际问题中如何去解决该类非孤立陀螺系统的运动稳定性问题。  相似文献   

6.
从代数学基本定理出发,将该定理加以引申,在复数域上n次方程x^n+an-1x^n-1+…+a0=0不仅有一个根,而且有n个根。并利用多项式的性质给出了一种证明方法.  相似文献   

7.
通过选取CH-γ方程中色散参数α和γ作为分支参数,基于平面动力系统的分支理论,利用相平面上特定的轨道,给出了该方程的一个新的孤立尖波解的解析表达式,证明了光滑孤立波和周期尖波解对孤立尖波解的收敛性质.  相似文献   

8.
借助一个非线性变换,在一定的假设下,利用Moser小扭转定理重新证明方程x^″+n^2x+φ(x)=p(t)所有解都是有界的,这一方法可极大地简化文献【1】中定理1的证明.  相似文献   

9.
利用椭圆函数积分,求出了非线性色散系统长波模型BBM 方程:ut + uux - δuxxt = 0的椭圆余弦波解,并给出了其孤立子表示.  相似文献   

10.
本文研究广义Zakharov-Kuznetsov方程ut+αupux+γuxxx+δuxyy=0的行波解.利用平面动力系统的分岔方法,本文得到了该方程孤立波解和周期波解存在的充分条件及这些解的隐式精确表达式,即它所对应的Hamiltonian系统的精确隐式解,并通过数学软件Maple模拟了这些解.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

15.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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