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1.
讨论了具有快速增长非线性项的Cahn-Hilliard方程ut г△^2u-△G(u)=0,G(u)=△↓^uφ(u),△↓^xun|x∈ЭΩ=△↓x(△u)n|x∈ЭΩ=0,u(0,x)=u0(x)解的长时间行为,构造了一个新系统,利用压缩映象原理,得到了该系统解的存在唯一性和一个m维光滑流形,即近似惯性流形,证明了Gahn-Hilliard方程的任意轨道在长时间后时入该流形的一个很小的领域中。  相似文献   

2.
研究了Lorentzian乘积空间Mn(c)×R1中具有平行平均曲率向量的双调和类空子流形.首先,证明了一般伪黎曼空间中具有平行平均曲率向量的双调和类空子流形的一个不变方程,然后利用该方程得到了Lorentzian乘积空间Mn(c)×R1中类空子流形是双调和的充要条件,并得到了这类子流形极小的充分条件.此外,还证明了一个关于Lorentzian乘积空间Mn(c)×R1中双调和类空超曲面的不存在性结果.  相似文献   

3.
将流形方法应用于对流扩散方程的数值求解,建立了基于标准Galerkin加权余量法的定常无源对流扩散方程的数值流形格式,采用一维定常无源对流扩散方程证明了物理覆盖的覆盖函数取完全一阶多项式的标准流形格式具有绝对的数值稳定性,并通过与一维对流扩散方程有限元解、精确解的对比,对该数值流形格式的稳定性进行了验证.同时,将基于四节点矩形有限单元覆盖系统的数值流形格式应用于二维平行管道中定常热对流扩散问题的数值分析.结果表明:在小的单元Pe(Pe<2)时,流形解的精度较有限元方法显著提高;在较大单元Pe条件下,一阶多项式覆盖函数的标准流形格式虽然绝对稳定,但假扩散作用显著,得到的数值解与真实结果存在较大的偏差.  相似文献   

4.
在文献[2]构造Stein流形上(p,q)型微分形式的带权因子的不变积分核基础上,通过H(o)rmander直径证明了Stein流形上具有非光滑边界强拟凸域上(p,q)型微分形式的(a)-方程带权因子解具有一致估计,并对该解进行了一致估计.  相似文献   

5.
讨论了Newton-Leipnik (N-L)系统的慢流形,利用两种不同的非标准分析方法,分别建立了N-L系统的慢流形方程.将慢流形局部地定义为正交于切丛系统的左快特征向量的平面,利用条件zT λ1 (X)·X ·=0,导出N-L系统的慢流形方程.并将慢流形看成由两个慢特征向量所生成的曲面,这两个慢特征向量对应J(X)的两个慢变变量特征值λ2(X)和λ3(X),得到N-L系统的慢流形方程.对其轨线的奇异性作了初步定性分析,描述了混沌吸引子的形成过程和系统相轨线动力学行为.  相似文献   

6.
利用张量分析方法, 结合Kenmotsu流形的结构方程, 考虑关于1/4对称度量联络平行的对称(0,2)型张量场的Eisenhart问题, 在适当条件下证明该张量场必为度量张量的常数倍, 并给出一个Ricci对称的Kenmotsu流形为Einstein流形的充要条件.  相似文献   

7.
在文献[2]构造Stein流形上(p,q)型微分形式的带权因子的不变积分核基础上,通过H rmander直径证明了Stein流形上具有非光滑边界强拟凸域上(p,q)型微分形式的-方程带权因子解具有一致估计,并对该解进行了一致估计.  相似文献   

8.
讨论了铁磁链方程解的长时间行为,通过压缩映象原理,构造了该方程的几类近似惯性流形,并证明了近似惯性流形在长时间后高阶逼近方程的整体吸引子.  相似文献   

9.
利用Painlevé分析的方法,对(1+1)维修正Broer-Kaup-Kupershmidt方程进行奇异流形展开,利用调谐因子项将展开方程有限项"截断",证明(1+1)维修正方程具有Painlevé可积性。在Painlevé分析的基础上,导出(1+1)维修正方程B■cklund变换和奇异流形满足的Schwarz导数方程,通过Schwarz导数方程的性质,求出方程的精确解。  相似文献   

10.
M为完备非紧的K(a)hler流形有非负的全纯双截曲率和极大体积增长且数量曲率二次退化的条件下,可以通过研究Poisson方程来解Poincaré-Lelong方程,并应用Poinicaré-Lelong方程研究和分析流形M的几何性质,文章主要研究了完备非紧非抛物的有渐近非负曲率n维K(a)hler流形M的Poisso...  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.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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   

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