首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
研究了双参数C半群的紧性。利用单参数C半群的紧性,得到了紧的双参数C半群的一些性质,从而推广了双参数C半群的相关结果。  相似文献   

2.
利用非紧性测度的性质与凝聚映射的Sadvoskii不动点定理,讨论了Banach空间中具有非紧半群的一类非线性发展方程周期解的存在性.  相似文献   

3.
研究了多参数C_0-半群的紧性。利用多参数C_0-半群和无穷小生成元的定义,给出多参数C_0-半群紧的定义,再根据C_0-半群的紧性,得到了紧的多参数C_0-半群的一些性质,从而推广了多参数C_0-半群的相关结果。  相似文献   

4.
利用相空间的方法,结合Hausdorff非紧性测度、强连续半群和Darbo不动点理论,研究相关半群在失去紧性的情况下,Banach空间中扰动型无穷时滞微分方程适度解的存在性,改进和推广了已有的一些结果.  相似文献   

5.
利用半群理论等方法讨论了抛物型非线性边界控制系统解映射的紧性。  相似文献   

6.
利用Hausdorff非紧性测度、线性算子半群和不动点理论,给出了当相关半群非紧等较弱的条件下,实Banach空间中一类双扰动的无穷时滞微分方程适度解的存在性.所用的方法可对相关半群是紧半群、扰动函数都是Lipschitz函数或者扰动函数为紧映射等情况进行统一处理.  相似文献   

7.
在Banach空间中探讨一类具有非瞬时脉冲的一阶积-微分方程适度解的存在性.在预解算子非紧的条件下,利用算子半群理论、非紧性测度理论和Darbo不动点定理,得到该类方程适度解的存在性结论.  相似文献   

8.
对Banach空间中的一类中立型无穷时滞微分方程引入适度解的定义,利用Hausdorff非紧测度、解析半群以及Darbo不动点理论,在不假没相关半群具有紧性条件下,得到此类方程适度解的存在性定理,对已有的一些结果进行了改进和推广.  相似文献   

9.
引入模糊拓扑半群的强Q紧概念,得出了模糊拓扑半群关于紧性的一些性质,同时还研究了模糊拓扑半群族直积的紧性.  相似文献   

10.
研究带有加性噪声项的Boussinesq型方程初边值问题的解的长时间动力学行为,首先通过一系列变换,把具有加性噪声项的随机微分方程转化为不具有噪声项的微分方程,由确定性理论得到该方程决定一个随机动力系统,然后利用周盛凡和范小明的方法[1-2]对一类算子进行估计,证明半群存在有界吸收集,且半群是一致渐近紧的,从而得到该半群存在全局吸引子.  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.
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   

15.
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   

16.
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   

17.
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   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<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   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号