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1.
本文通过集值映射扩张刻画了k-半层空间和k-MCM空间.证明了以下结果:对于空间X下列论断等价:(1)X是k-半层空间;(2)对每个度量空间Y,存在保序算子Φ使得对每个集值映射φ:X→F(Y)都对应下半连续和k-上半连续集值映射Φ(φ):X→F(Y),使得Φ(φ)(x)在每个点x∈Uφ有界并且φ■Φ(φ),这里F(Y)是Y的所有非空闭集,Uφ={x∈X:φ在点x局部有界}.  相似文献   

2.
令X为度量空间,将定义在X上的下半连续有上界、上半连续有下界的实值函数f转化为集值映射F,通过Aubin定理,证明F在X上通有连续,进而证明f在X上通有连续,最后给出了定义在拓扑空间上的半连续实值函数通有连续性的一个直接证明。  相似文献   

3.
本文研究了从赋范空间X到完备向量格赋范空间(Y,S)上的凸算子F的连续性及次可微性,给出了算子F 下半连续的一种新的局部性描述,将“下半连续的凸函数在其有效区域内部是连续的”推广到了凸算子上,并且证明了“凸算子F 在其有效区域内部某一开子集上序上有界,则F 在其有效区域内是局部Lipschitz 的”。在推广了Hahn-Banach 定理的基础上,证明了凸算子F 在其有效区域内是次可微的.  相似文献   

4.
为了进一步研究极小极大不等式,首先引进了H-空间,将极小极大定理中的闭性条件与凸性条件进一步削弱,利用反证法与有限交性质将Fan-Ha截口定理以及极小极大定理推广为非线性H-空间上更一般的形式设(X,{ΓA}),(Y,{ΓD})为2个HausdorffH-空间,BCX×Y,且满足如下条件a.对每个x∈X,{y∈Y,(x,y)B}为H-凸集或空集.b.对每个y∈Y,{x∈X,(x,y)∈C}为X中的紧闭集.c.对每个x∈X,存在AxX×Y,Ax=Px×Qx.其中Px为X中的紧闭集,Qx为Y中的紧集.d.又假设存在X的非空紧集K,对每个X的有限子集N,存在X的紧子集LN,LNN,使得①对每个y∈Y,LN∩{x∈X,(x,y)∈Az,对所有z∈LN}是零调的;②对每个x∈LN\K,{y∈Y,(x,y)∈Az,对所有z∈LN}{y∈Y,(x,y)∈B};e.对每个x∈K,{y∈Y,(x,y)∈Az,对所有z∈X}=.则存在x0∈X,使得{x0}×YC.利用广义的Fan-Ha截口定理,容易将参考文献[1]中的所有结论推广到H-空间上.  相似文献   

5.
局部凸拓扑矢量空间内的广义拟变分不等式   总被引:3,自引:10,他引:3  
设X是局部凸空间E的仿紧凸子集 ,F :X→ 2 X 是集值映象 ,φ :X×X→R是实泛函 .研究下列抽象广义拟变分不等式 (AGQVI) :求 ^x∈X使得 ^x∈F(^x)和 φ(^x ,y)≤ 0 , y∈F(^x) ,其中 φ(x ,y)关于x是 0 转移紧下半连续的和关于y是 0 对角拟凹的 .作为应用 ,作者得到了最近文献中关于广义拟变分不等式的很多已知结果的推广 .  相似文献   

6.
设 X 为复的 Banach 空间,L(X)为 X 上的有界线性算子构成的 Banach 代数,F为L(X)到L(X)的线性算子.Matj(?)z Omladi(?)在[1]中证明了下面的定理.定理设 F:L(X)→L(X)是线性、双射且在弱算子拓扑下连续的映射,F 和 F~(-1)均保持一秩投影,则或者(1)存在一个有界的双射线性算子 U:X→X,使 F(A)=UAU~(-1),或者(2)存在一个有界的双射线性算子 U:X′→X,使 F(A)=UA′U~(-1),在此情形下 X 是自反的.下面给出此定理的一个简单证明,并对其条件进行改善,推广该定理.本文中 X、Y 表示 Banach 空间,X′、Y′分别表示它们的对偶空间,任意 x∈X,f∈X′,x(?)f 表示如下定义的 X 上的一秩算子,任意 y∈x,(x(?)f)(3y)=f(y)x.以下两个引理均设 F 为 L(X)到 L(Y)的保持一秩投影的线性映射,且 F 限制在 L(X)中的一秩算子组成的集合上为单射.引理1 若 x、y∈X 为线性无关向量,f∈X′为非零函数且 f(x)=f(y)=1,则存在 u、  相似文献   

7.
将半开集和半连续的概念引入直观模糊特别拓扑空间, 得到它们的一些性质:一个直观模糊特别集是直观模糊特别半开集的充要条件是 A cl[ int(A) ] ; 直观模糊特别半开集族的任意并是直观模糊特别半开集; 直观模糊特别开集是直观模糊特别半开集; ( X,τ)的子空间( ( Y,φ)中的集合 A 是( X,τ)中的半开集,则它也是( Y,φ)中的半开集; 连续函数是半连续的,但逆不成立; 强半连续是半连续的, 但逆不成立;函数 f 是半连续的当且仅当对于f ( x ) O, O 是 Y中的直观模糊特别开集,存在 X 中的直观模糊特别半开集A 使x  A 且f (A ) O; 函数 f 是强半连续的当且仅当 Y中的每一直观模糊特  相似文献   

8.
研究斜积系统F:X × Y→X × Y,F(x,y) = (f(x),g(x,y))上连续函数φ(x,y)纤维方向的增长率.我们证明了如果μ是f-遍历测度,则∧(μ)=max ∪∈uμ(F) ∫X×Y φd∪ 及 λ(μ)=lim n→∞ 1/n max y∈Y ^n-1∑i=0 φ(F^i(x,y))=constant 对μ a.e.x是一致的。  相似文献   

9.
为了刻画k-半层空间引进k-半连续集值映射的定义,通过集值映射扩张刻画了k-半层空间和k-MCM空间. 住要证明了:对于空间X下列论断等价:(1)X是k-半层空间;(2)对每个度量空间Y,存在保序算子$\Phi$使得对每个集值映射$\varphi: X \rightarrow \mathcal {F}(Y)$都对应下半连续和k-上半连续集值映射$\Phi(\varphi): X \rightarrow \mathcal {F}(Y)$使得 $\Phi(\varphi)(x)$ 在每个点$x\in U_\varphi$有界并且$\varphi\subseteq \Phi(\varphi)$.  相似文献   

10.
本文在一个给定的距离空间的基础上,构造一个新的距离空间,进一步讨论两个空间之间的关系及新距离空间的一些性质。 设E是一个以d为距离函数的距离空间,而且d是有界的,即存在一个正数M使对任意的x,y∈E有d(x,y)≤M。令F(E)表示E的一切非空闭子集所组成的集合,现在我们就在F(E)上定义一个距离函数h。若X、Y∈F(E)令  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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