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1.
几个非线性发展方程的精确显式孤立波解   总被引:1,自引:0,他引:1  
解析地研究了几个具有物理背景的非线性发展方程的孤立波解,通过选取初始条件结合直接积分方法求出了非线性Pochhammer-Chree方程、MRLW方程和SRLW方程及其推广,Zakharov-kuznetsov方程和Kadomtzev-Pitviashivili方程及其推广的显式精确孤立波解与SRLW方程的另一族精确行波解.  相似文献   

2.
sille-Gordon型方程出现在微分几何的研究中,它在非线性光学、生物物理、离子物理、非线性晶格和超导物理的Josephson结构等物理领域中有着广泛的应用,近年来,人们已经找到sille-Gordon型方程的许多新的精确解,如文[1]用一种辅助方程的解构造了sille-Gordon型方程的新的精确解,虽然双曲正切函数法和齐次平衡法对sille-Gordon型方程和Schroedinger型方程没有直接效果,但它们经过特殊变换后也可以用双曲正切函数法和齐次平衡法求解,本文用新辅助方程和函数变换构造了sille-Gordon型方程、双sille-Gordon方程等几个方程的新的精确孤立波解。  相似文献   

3.
解析地研究了几类具有物理背景的非线性发展方程,用行波方程得到了这些方程的显著精确解,这些解为有理分式形式的孤立波解。  相似文献   

4.
反应扩散方程描述了物质的输运、扩散和流动等物理过程,其精确解的构建在数学、物理、化学、生物等领域有其重要的应用意义.运用广义的Riccati方程代换法解Chaffee-Infante反应扩散方程,获得了27种形式的解,丰富了精确行波解的形式.推广运用该方法,可以构建其它类型的非线性反应扩散方程的行波解.  相似文献   

5.
为了研究非线性色散对Compacton和孤立波形成的作用,对非线性Camassa-Holm方程增加一色散项(ul)3x后得到广义色散Camassa-Holm方程.拟设该方程具有4种形式解,得到了丰富的精确解.讨论了在各种不同的非线性参数条件下,得到单峰、双峰Compacton解、斑图解、孤立波解、周期波解以及Kink Compacton解.研究了高维广义色散Camassa-Holm方程的精确解.结果表明,非线性和色散的相互作用是形成孤立波的关键.  相似文献   

6.
几个非线性发展方程的精确显式孤立波解   总被引:2,自引:0,他引:2  
解析地研究了几个具有物理背景的非线性发展方程的孤立波解,通过选取初始条件结合直接积分方法求出了非线性Pochhammer-Chree方程、MRLW方程和SRLW方程及其推广,Zakharov0kuznetsov方程和Kadomtzev-Pitviashivili方程及其推广的显式精确孤立波解与SRLW方程的另一族精确行波解。  相似文献   

7.
为研究(3+1)维非线性波动方程的精确解,通过利用不变集方法,得到了(3+1)维非线性波动方程的一些新精确解。该方法也可以用来求解其他非线性偏微分方程。  相似文献   

8.
扩展了最近提出的G’/G展开法,当方程系数满足一定约束条件时,用扩展后的方法得到了变系数非线性薛定谔方程带有任意参数的精确解,包括双曲函数解、三角函数解以及有理函数解。当精确解中的参数取特殊值时,由该方程的双曲函数解得到其著名扭状孤立波解。分析结果表明:该方法直接有效,可用于研究数学、物理中其他非线性变系数演化方程。  相似文献   

9.
目的 研究一类在物理,化学反应,生物数学以及土壤学等领域具有广泛应用的非线性扩散方程.方法 运用条件Lie-B(a)cklund对称和不变子空间相结合的方法求非线性扩散方程的精确解.结果 对于非线性扩散方程进行完全分类.结论 得到了非线性扩散方程的更丰富的解.  相似文献   

10.
形式变量分离方法是寻找非线性物理方程孤子解的一种行之有效的方法,运用此方法得到了偶合KdV方程的精确两孤波解。  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.
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   

14.
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   

15.
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   

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.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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