二阶抽象微分方程的多项式有界解的极大子空间

受文de Laubenfels[1](1997,Isreal Journal ofM athem atics,98:189~207)的启发,引进空间W(A,k)和H(A,ω),它们分别是使得该二阶抽象Cauchy问题有在[0,∞)一致连续且O((1 t)k)有界和O(eωt)有界的弱解的x∈X的全体.讨论Banach空间X上二阶抽象Cauchy问题的具有多项式有界解或指数有界解的极大子空间问题.由W ang and W ang[2](1996,Functional Analysis in Ch ina.K luwer,333~350)知,该Cauchy问题适定的充要条件是该Cauchy问题中的X上闭算子A生成一个强连续Cosine算子函数.处理该Cauchy问题不适定的情况.证明或指出了如下结论:.W(A,k)和H(A,ω)均为Banach空间,且W(A,k)和H(A,ω)均连续嵌入X;.部分算子A|W(A,k)生成一个多项式有界的余弦算子函数{C(t)}t∈R ,使‖C(t)‖W(A,k)≤2(1 t)k;.部分算子A|H(A,ω)生成一个指数有界的余弦算子函数{C(t)}t∈R ,使‖C(t)‖H(A,ω)≤2eωt;.W(A,k)和H(A,ω)分别是极大的.即若有Banach空间Y连续嵌入X,且使A|Y生成一个O((1 t)k)有界的余弦算子函数,那么Y连续嵌入W(A,k);而若使A|Y生成一个O(eωt)有界的余弦算子函数,那么Y连续嵌入H(A,ω).     

n阶α次积分C半群的逼近

借助算子半群逼近的相关理论及经典算子理论的研究方法,对算子A,An分别次生成的n阶α次积分C半群{T(t)}t≥0和{Tn(t)}t≥0,在一定条件下,当Tn(t)x逼近于T(t)x,则有Rc(λ,An)x逼近于Rc(λ,A)x,反之也成立.从而丰富了n阶α次积分C半群的研究内容.     

一类θ二阶非齐次抽象微分方程

本文讨论了有界变差余弦算子函数,证明了自反的Banach空间中,二阶抽象Cauchy问题υ"(t)=Aυ(t)十g(t),t∈[0,T],υ(0)=x∈D(A),υ'(0)=y∈D(A)关于一切g∈C([0,T],X)的mild解均为古典解的充分且必要条件是A为有界线性算子.     

K—正则预解算子族的谱映象定理

设k∈C（R^＋），A是Banach空间X中的闭稠定线性算子，且A生成一个指数有界的k-正则预解算子族R（t）。证明了A谱和R(t）谱之间的一些关系，并由此获得预解算子族，积分半群，积分余弦函数C0-半群，强连续余弦函数的相应结果。     

指数有界双连续n阶α次积分C半群的逼近

利用经典算子半群理论中的研究方法，基于双连续n阶α次积分C半群的生成定理，讨论了指数有界双连续n阶α次积分C半群的逼近定理。{T(t)}_t≥0，{Tn(t)}_t≥0分别是由A、A_n次生成的指数有界双连续n阶α次积分C半群，在一定条件下，可以得到Ra(λ，A_n) x→Ra(λ，A) x与T_n(t)x→T (t)x等价。研究结果推广了n阶α次积分C半群相关的逼近定理。     

关于最终一致连续半群特征的一个注

设{T(t)}是Hilbert空间H上的一个有界线性算子C0半群,A是其无穷小母元,α0满足α0＞limt→+∞||T(t)||/t.本文证明了在上述条件下,当t＞t0(t0≥0)时T(t)按一致算子拓扑连续的充分必要条件是,对任意的δ＞0,lim u→+∞ x∈H,sup||x||=1,t＞t0+δ||∫|τ|≥αeitτR(α0+iτ,A)xdτ||=0.     

C半群的一些性质

引入C半群新的条件:(A1)存在θ∈(π/2,π]使得,(1)对每一个t∈[0,T],ρ(A(t))(>){λ:∣argλ∣<θ} U {0}l,(2)存在常数M使得∣∣ R(λ,A(t))c ∣∣≤MI/∣λ∣,λ∈∑,t∈[0,T].(A2)对于任意λ∈∑,t的算子值函数R(λ,A(t))C,t∈[0,T]依算子拓...     

弱条件线性方程组的一种迭代方法

设A为m×n矩阵、线性方程组AX=b相容,其解集为C。给出了求X∈C的迭代方法。对序列{X(k)},其中λit(k)X(k)满足: X0,X(k+1)=X(k)+ mi=[bi-(Ai,X(k))]/‖Ai‖2,k=0,1,2,…。证明了{X(k)}收敛,设i,Ai,t(k)i=1X(k)=X ,则X ∈C。若取X0=0,则X ∈R(AT),其中R(AT)={ATX｜X∈Rm}。limk→∞     

一类算子的谱理论(Ⅰ)——(AC)算子的基本性质

设X是复B-空间,B(X)是X上有界线性算子全体,C是复平面,F是C的一切闭子集类,我们引入一类算子,并研究它的谱理论,算子T∈B(X)称为(AC)算子,若T有性质(A)与(C),我们证明:(1)T∈B(X)是(AC)算子当且仅当对F到X的闭子空间类的同态X(·)满足下述条件:(ⅰ)(F_1∩F_2)=X(F_1)∩X(F_2);(ⅱ)X(φ)={0},X(C)=X;(ⅲ)TX(F)X(F);(ⅳ)σ(T|X(F))F;(ⅴ)对x∈X若存在解析函数x(λ):CF→X,使(λI-T)x(λ)=x,则x(λ)∈X(F),λ∈CF,(2)设T∈B(X)是(AC)算子,则对任何F∈F,有:(ⅰ)若X_T(F)≠{0},则F∩σ(T)≠φ;(ⅱ)若X_T(F)={0},则F∩σ_p(T)=φ,(3)设T∈B(X),σ(T)位于光滑Jordan曲线Γ上,又对每个z∈Γ,存在Γ邻域V上非零解析函数f(z),使 ‖f(z)R(λ,T)‖≤M_z,λ≠z,λ∈V,M_z>0,则T是(AC)算子。     

最终范数连续半群的一些性质

主要讨论了Banach空间中当t＞t0（t0≥0）时，最终范数连续半群{T（t）│t≥0}的性质，给出了最终范数连续半群无穷小生成元的一个谱分布性质．主要定理如下：设{T（t）lt≥0}是Banach空间X上的C0半群，A是其无穷小生成元，ω0=inft＞0（1/t1n‖T（t）‖）．若T（t）关于t＞α≥0是最终范数连续的，则存在一个减函数φ：（0，∞）→R，满足φ（M）→-∞（M→∞）且S={λ∈C│Reλ≥φ（│Imλ│） }lReA≥P（1ImAl）}包括于ρ（A），其中ρ（A）为A的预解集．     

Markedness and its Interpretation in Language Use

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Features of Women's language

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

An Index mechanism for multi-scale view in spatial databases

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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