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1.
M是有限群G的一个给定极大子群,如果G的子群C不包含在M中,但是C的每个G-不变真子群都被M包含,那么就称C是M的一个完备。如果完备C同时还满足下列条件:或者C=D,或者C是子群D的一个极大子群,其中D不是M的完备,则称C是M的一个S-完备.利用极大子群的S-完备刻画了有限可解群.  相似文献   

2.
讨论了交换C^*-代数C(Ω)上矩阵的谱与广义谱,给出了A∈Mn(C(Ω)的谱σ(A)与相应的A(ω)∈Mn(C)的谱σ(A(ω))的一个关系。引入了A∈Mn(C(Ω))的广义谱σg(A),讨论它的一些性质,证明了σg(A)是C(Ω)中的一个闭集,并且一般是无界的。  相似文献   

3.
应用Logistic模型拟合彩色遥感图像的D-t曲线,是定量分析Y(黄),M(品红),C(青)分解密度与曝光时间关系的一种新方法。结果表明,Y,M,C分解密度的预测值与实测值达到了较好的吻合。决定系数RY^2=0.9825,RM^2=0.9675,RC^2=0.9943,相应的标准偏差σT=0.053,σM=0.100,σC=0.015,可以满足定量计算的精度要求。  相似文献   

4.
Adm猜想初探     
有向图的Adam猜想是图论中的一个尚未解决的问题。本文根据有向图中含一已知弧的有向圈数目同这弧的从头到尾的有向路数目的相等关系得到Adam猜想的一个等价命题:若D是包含有向圈的有向图,则存在某弧,把它反向之后将减少D中有向圈的数目当且仅当在D中存在一条弧(v_i,v_j),满足r_(?)≤r_(ij),其中r_(ij)表示D中从点v_i到点v_j的有向路的数目。据此我们可以证明Adam猜想对满足一定条件的许多有向图是成立的。  相似文献   

5.
B.D.Acharya和S.M.Hcgdc猜想[1]:(1)、如果圈C4t 1是(k,d)的算术图,那么必有k=2td 2r,其中r是某个非负整数;(2)如果圈C4t 3是(k,d)算术图,则k=(2t 1)d 2r,其中r是某个非负整数。本文对以上猜想给出了肯定性证明。  相似文献   

6.
冯颖  陈滋利 《江西科学》2005,23(2):102-105
以实f-代数的理论作为基础,给出了半素和有单位元的复,代数的一些性质。证明了逆元存在的一个充分条件;并考察了在正规的条件下,复f-代数何时有乘法分解(M.D)性质和(*)性质。最后对复f-代数中的序理想和代数理想的关系进行了刻画。  相似文献   

7.
1.设M是所有n阶方阵所构成的代数,方阵的元素属于域K,σ是M内的一个一一对应。如果σ合于下面三个条件,那末我们就把它叫做矩阵代数M的一个自同构。(i)σ(aI)=aI(ii)σ(A+B)=σ(A)σ(B)(iii)σ(AB)=σ(A)σ(B)  相似文献   

8.
在形式背景的对象集合幂集P(G)和属性集合幂集P(M)上定义了偏序关系.证明了偏序集(P(C),≤)或(P(M),≤)与概念格U(K)之间存在序同构关系.给出了一种利用序同构关系构造U(K)中所有概念的内涵和外延的方法.所得的若干定理拓展了文献中的研究结果.  相似文献   

9.
作为统计收敛模糊数列空间的推广,基于Orlicz函数,在义模糊数列强Pre-Cauchy收敛的基础上,提出并研究模糊数列空间W(M,C, p)。同时,讨论模糊数列空间W(M,C, p)与统计Pre-Cauchy收敛的模糊数列空间S(C)之间的包含关系。  相似文献   

10.
三角对称SmODA晶体中Sm3+离子的配位场理论研究   总被引:1,自引:0,他引:1  
采用点群链R(3)*O*D3*关系来标记D3*点群的斯塔克能级.基于双层点电荷配位场(DSCPCF)和经典的简单点电荷配位场(PCF)两种模型,利用自编的计算程序对三角对称(D3)的[Sm(C4H4O5)3].2N aC lO4.6H2O(简记为SmODA)晶体中Sm3 离子的45个配位场微扰能级进行了理论计算和归属,计算结果与实验能级进行比较,DSCPCF模型得到的均方根偏差(σ)为21.22 cm-1,而PCF模型计算的σ为33.43 cm-1,表明前者模型更为优越,它是基于实际的配位结构并且仅包含较少的拟合参数.  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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