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1.
研究旋转作用下无磁耗散的磁Rayleigh-Bénard问题的稳定性.建立了旋转作用下的磁Rayleigh-Bénard问题的稳定性条件,并在该条件下证明磁Rayleigh-Bénard问题存在全局的稳定性解,该解关于时间代数衰减.  相似文献   

2.
著名的上下解方法使用的一个基本条件是方程的下解小于上解,但在很多非线性问题中下解及上解不满足这一条件,即下解不小于上解,本文对全连续增算子在下解不小于上解的基本条件下,获得了新的不动点定理,并应用于超线性积分方程.  相似文献   

3.
利用凝聚函数对线性互补问题的等价形式进行带参数的磨光, 并对参数方程的解曲线进行离散化追踪, 在无假设有严格互补解的条件下, 给出一个新的算法. 在适当条件下, 证明该算法具有大范围线性收敛和局部任意阶收敛性.  相似文献   

4.
应用度理论研究了一类离散的非线性反应扩散方程,得到了波前解的存在条件,并在一定条件下,使用上下解方法证明了改型的离散方程的解收敛到连续问题的波前解.  相似文献   

5.
应用度理论研究了一类离散的非线性反应扩散过程,得到波前解的存在条件,并在一定条件下,使用上下解方法证明了改型的离散方程的解收敛到连续问题的波前解。  相似文献   

6.
关于带跳反射扩散过程的下鞅问题及其应用   总被引:2,自引:0,他引:2  
提出一个联系于一类在上半空间上带泊松跳的反射扩散过程的下鞅问题,并在一组较弱的条件之下证明该下鞅问题的解的存在性。进而讨论了这一类下鞅问题的解与一类在上半空间上具有反射边界的带泊松跳的随机徽分方程的解的关系,并在一定的条件下证明了这两种解的一种等价关系。  相似文献   

7.
讨论了一个抛物型偏微分方程动态边值的初值控制问题. 在一定条件下得出了上下解的有序性, 并由此引入迭代序列讨论了整体解的存在性以及计算办法, 并给出了问题具有无穷多解的算例.  相似文献   

8.
研究了线性流形上 D反对称矩阵反问题的最小二乘解及其逼近问题 .给出了最小二乘解的一般表达式 ,并就该问题的特殊情况 :矩阵反问题 ,证明了可解的充要条件 ,并在有解的条件下给出了解的一般表达式 .得到了最佳逼近解的表达式 .  相似文献   

9.
利用Poincare映射及其不动点的分支,研究一维周期微分方程解的重数及其扰动分支,提出未扰动系统出现多重周期解的条件,并给出了一些特殊方程零解的具体重数作为应用;讨论多重周期解在扰动下产生一个或多个周期解的问题,获得了周期解的存在条件。  相似文献   

10.
讨论一般线性约束下伪线性规划的多重解问题.推导出解的一般表达式.并基于XH算法,提出解的唯一性条件以及当唯一性条件不满足时确定全部解的计算步骤.从而推广了文献"一般形式线性分式规划解集的结构与求法"的结果.  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.
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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