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1.
作者主要对一类非局部反应扩散方程的爆破性质进行了研究,得出了有限时刻爆破解或整体解存在的最优指数,并对爆破解研究了爆破率和爆破集.  相似文献   

2.
研究了带有齐次Dirichlet边界条件的非线性非局部源的退化奇异抛物型方程组解的爆破性质,建立了古典解的局部存在性。在适当的假设条件下,得出了正解的整体存在与有限时刻爆破的结论。  相似文献   

3.
利用上、下解方法和比较原理,研究了一类带有对流项和吸收项的反应扩散方程的非负有限行波解。得出了该方程行波解的唯一性,局部存在性,整体存在性和爆破的充要条件。  相似文献   

4.
利用正则化方法讨论了一类退化方程组初边值问题的古典解的存在性,构造特征函数,通过上、下解方法得出了解全局存在以及爆破的充分条件.  相似文献   

5.
文章主要探讨了一类带有特殊边界条件的反应—扩散方程组解的爆破或整体存在的充分条件.给出方程组上、下解的定义,由比较引理,利用上、下解方法,得出定理的证明.这种研究偏微分解的性质的方法具有一定的代表性.  相似文献   

6.
多孔介质方程具有广泛的物理背景,可用于刻画流体流动、热传导等在内的物理过程.首先利用凸方法证明了初值充分大时存在有限时刻爆破的解;再利用极大值原理结合积分估计等得出爆破解的爆破速率估计;最后利用L2方法得出爆破解的爆破时间估计,所得结果与初值和势函数V(x)都有关系.在所研究的方程中将势函数取作V(x)≡1,便得到了最典型的具有源项的多孔介质方程.  相似文献   

7.
研究了一类带有对流项的非线性抛物型方程的非负有限行波解.得出了该方程解的唯一性,局部存在性,整体存在性,和“爆破”的充分必要条件.  相似文献   

8.
研究在磁场中一类带调和势的非线性Schr?dinger方程.通过分析方程的性质,结合Gagliardo-Nirenberg不等式,得出在正能量情况下其解整体存在和爆破的门槛条件.  相似文献   

9.
考虑了半线性热方程ut=Δu-V(x)u+a(x)up在非线性非局部的边界条件u(x,t)=∫ΩK(x,y)ul(y,t)dy下解的性质,通过构造上、下解,得出方程的解整体存在和有限时刻爆破的充分条件.  相似文献   

10.
一类半线性热传导系统解爆破的渐近行为   总被引:1,自引:1,他引:0  
研究半线性热传导系统{ut=uxx λv,vt=vxx ku,得出了该系统在爆破点的一个领域内,当t接近有限爆破时间T<∞时,该系统对称解的渐近行为,同时用相似变量的方法得出了其增长速度。  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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