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1.
通过研究H_0~1(Ω)的对偶空间H~(-1)(Ω),发现H~(-1)(Ω)的Riesz表示唯一,但在(L2(Ω))N+1中的表示不唯一.同样地,对于W_0~(1,p)(Ω)的对偶空间W-1,p'(Ω),在W_0~(1,p)(Ω)有唯一表示,但在(Lp'(Ω))N+1中的表示不唯一.  相似文献   

2.
考虑带非局部扩散的非自治抛物方程解的长时间行为,当时间符号项于L_(loc)~2(R;H~(-1)(Ω))和L_(loc)~2(R;L~2(Ω))中平移有界时,证明该系统所对应的过程在L~2(Ω)与H_0~1(Ω)中存在一致吸引子。  相似文献   

3.
一类微分算子生成的半群与发展方程初值问题的解   总被引:1,自引:1,他引:1  
本文首先给出并讨论了一类广义微分算子A_(2k)=(-1)~(k-1)D~(2k);(A_(2k-1)=(-1)~(k-1)D~(2k-1))在定义域H~(2k)(H~(2k 1)))上生成的强连续半群.讨论了算子及其生成半群的自伴性,谱性,并将其应用于发展方程Cauchy问题,给出了一类线性偏微分方程的解.  相似文献   

4.
基于R -T空间Vh×Wh H(div;Ω)×L2 (Ω) ,本文讨论了Sobolev方程 -div{α ut+b1 u}=f的初边值问题混合有限元方法的最大模误差估计 .得到了数值解在L∞( 0 ,T ;L∞(Ω) )模下的拟最优阶误差估计 (有限元空间指数k =0 )和最优阶误差估计 (有限元空间指数k≥ 1)以及在L∞( 0 ,T ;L∞(Ω) 2 )模下的拟最优阶误差估计 .  相似文献   

5.
讨论了带有线性记忆项和混合微分项的弱阻尼波方程解的长时间行为.证明了方程在非线性项满足临界增长条件下,在空间H_0~1(Ω)×L~2(Ω)×L_μ~2(R+,R_0~1(Ω))中存在全局吸引子,其中半群的紧性通过压缩函数方法得到.  相似文献   

6.
本文定义了k维可选过程对k维拟左连续局部鞅的随机积分,然后建立了k维拟左连续局部鞅的可选表示性基本定理,这推广了一维情形下严加安、Yoeurp[1]中的相应结果.设(Ω,F,P)为完备概率空间,(F_t)_(t≥0)为F的子σ域族,满足通常条件.本文采用如下记号:M_0~b—零初值有界鞅空间,L_0—零初值局部鞅空间,H~1—H~1鞅空间,H_0~1—零初值H~1鞅空间.本文中随机过程符号右上角的数字都是附标,若要表示幂次,则加括号后再写上幂次.若M~1,M~2,…,M~k为拟左连续局部鞅,则称M=(M~1,M~2,…,M~k)为k维拟左连续局部  相似文献   

7.
考虑Laplace算子在Dirichlet边界条件下的特征值和特征函数的性质问题,利用变分方法给出了Laplace算子的特征值和特征函数的存在性。运用特征值序列趋向于无穷大,首先证明了特征函数系在空间H_0~1(Ω)中是一组正交完备系,然后利用空间H_0~1(Ω)在空间L~2(Ω)中的稠密性,证明了特征函数系在空间L~2(Ω)中是一组标准正交完备系,最后利用二阶椭圆型偏微分方程解的L~2先验估计结果,给出了特征函数系在空间H~2(Ω)∩H_0~1(Ω)中是一组完备系。对经典知识给予了深刻发掘,并给予严密完善的证明。  相似文献   

8.
设 S(t,x)=π~(-1)argL(1/2+it,x)A.Fujii 在[1]中研究了integral from T+H to T(S(t+h,x)-S(t,x))~2dt并给出了一个渐公式。本文研究更一般情况。得到如下结果:定理1 设 T~(1/2+a)≤H≤T,(A>0),00),00为任取的实数。当 T≥T_0(a,δ)时,我们有  相似文献   

9.
本文研究R~n中任一个有界集的外域上SObolev方程的初边值问题 是R~n中任一有界集的外域且其边界■Ω光滑. 假设有:m≥2[n/2]+3,ρ(x),ψ(x)∈H~(2(m-1))(Ω);a_(ij)(i,j=1,2,…n)及f∈■w~(k·∞)(0,T;H~(m-k-1)(Ω)),则(G)存在唯一的经典解.  相似文献   

10.
广义神经传播型非线性拟双曲方程解的熄灭性   总被引:1,自引:0,他引:1  
本文对广义神经传播型非线性拟双曲方程具第一类边界条件的初边值问题,得到了其解的递增解的熄灭性,并进一步讨论了他的C~(?)(O,T,H~2(Ω))∩C~2(O,T,L~2(Ω))解的熄灭现象。  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
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   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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