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1.
文[1]给出了方程(1)的延拓结构,并由延拓结构引出了方程(2),(3),(4),本文在此基础上,通过适当变换给出这些方程以及与它们密切相关的一些方程的联系,并讨论了有关方程的对称和强对称,为更进一步讨论其它问题奠定基础。  相似文献   

2.
研究了二维热传导方程的非古典对称的决定方程,对于一般的一维偏微分方程,运用向量场的延拓和不变表面条件及初始方程的相容性两种方法得出了相同的非古典对称的决定方程.由此,得到了利用不变条件及初始方程的相容性也可求得非线性偏微分方程的非古典对称的决定方程的重要结论.最后,将此结论推广到二维热传导方程,证明了该结论对于二维热传导方程也是可行的.  相似文献   

3.
Boussinesq方程的非古典对称和相容性   总被引:2,自引:1,他引:2  
研究了一类任意阶的非线性偏微分方程的非古典对称的决定方程,比较了非古典对称和古典对称求解方法的不同,在求解非线性古典对称的过程中,引用了一个简单的偏微分方程,运用向量场和其延拓以及不变表面条件和初始方程的相容性两种方法求出了相同的非古典对称的决定方程,由此,得出了利用不变表面条件和初始方程的相容性也可以求得非线性偏微分方程的非古典对称的重要结论.以Boussinesq方程为例,证明了该结论的可行性.  相似文献   

4.
首先给出P—Henon方程边值问题保持D4对称的有限元离散方程,然后以P为参数,用Newton延拓法计算出具有不同对称性质的多解.  相似文献   

5.
研究了Benney方程的非古典对称,运用向量场和其延拓,以及不变表面条件和初始方程的相容性两种方法得出了相同的非古典对称的决定方程。由此得到了利用不变条件和初始方程的相容性也可求得非线性偏微分方程的非古典对称的重要结论。  相似文献   

6.
主要研究左对称超代数上奇型的超O-算子,研究了左对称超代数上的超S-方程的解与超O-算子之间的关系,进一步找到在左对称超代数上奇型的超O-算子与左对称超代数和表示空间的对偶空间的直和空间上的超S-方程的解的关系.给出了左对称超代数上超2-上循环的定义,研究了左对称超代数上超S-方程的解与超2-上循环之间的关系.  相似文献   

7.
本文给出了“延拓方程”和“条件强对称”两个概念,并以方程(4)为例, 讨论了与“条件强对称”有关的几个命题。  相似文献   

8.
超对称理论(SUSY)是TeV能级以上新物理的一种备受关注的可能理论框架.在该理论中,预言了超对称伴粒子的存在.其中,超对称粒子-最轻标量轻子τ1的寿命可能比较长,有可能与其他粒子形成超对称束缚态.采用Spinless Salpeter方程来描述超对称束缚态.Spinless Salpeter方程是Bethe-Salpeter方程的一种很好的近似,是Schrodinger方程的相对论推广.一般情况,Spinless Salpeter方程没有解析解,所以用数值方法求解Spinless Salpeter方程得到超对称束缚态τe,τμ,τp(或它们的反粒子)的质谱(或者束缚能).  相似文献   

9.
延拓结构理论是求非线性演化方程拉克斯对、贝克隆变换、守恒量等的一种重要方法,由该方程的拉克斯对可以检验其可积性.基于非交换外微分,这一理论最近被推广到微分差分方程中去了.在本文中,利用半离散的延拓结构理论讨论了形变KdV(MKdV)方程的一个离散模型,得到了其延拓结构和拉克斯对,由此检验了这一方程的可积性.  相似文献   

10.
讨论一类带正权函数超线性对称方程对称周期解的分布情况.运用相平面定性分析的方法,得到了在关于时间映射的超线性条件下,方程无穷多个对称调和解的存在性以及对称次调和解的稠密性分布结果.  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
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   

19.
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   

20.
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   

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