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1.
康托集分解为2^n个分离闭子集C=C1∪C2∪…C2n,则存在f:C→C满足,同胚映射f:Ci→C2n-1+ix〈Y∈Ci,f(x)〈f(y)或x〈y x∈Ci y∈Ci,f(x)〉,f(y)i=1,2…2^n-1 f:C2n-1+j→Cj x〈y x∈C2n-1+j y∈C2^n-1+j f(x)〈f(y)或f(x)〉f(y)j=1,2…2^n-1,f :E^n→E^n,n〉m≥1 f连续映射.至少有不可数多个反极点Pα—Pα α∈A A不可数.f(Pα)=f(-Pα).  相似文献   

2.
徐保根  汤友亮  罗茜 《江西科学》2011,29(5):546-549
设G=(V,E)是一个非空图,对于一个函数f∶V(G)∪E(G)→{-1,1},则称f的权重为w(f)=∑x∈V(G)∪E(G)f(x)。若x∈V(G)∪E(G),定义f[x]=∑y∈NT[x]f(y)。如果对所有的x∈V(G)∪E(G)都有f[x]≤1,则称f是图G的一个反全符号控制函数。G的反全符号控制数定义为γ*...  相似文献   

3.
宋丽丽 《科技信息》2010,(18):I0090-I0090
设三次多项式f(x)=x3+tx2-ux-1∈Z[x],则存在t,u∈Z使得f(x)有惟一的一个实数根θ〉1,并且θ是三次域K=Q(θ)的基本单位。  相似文献   

4.
令P(f)={t∈R| x∈D有x±t∈D且f(x+t)=f(x)}, (f)={f(x)|x∈D}.本文主要探讨利用P(f)度量函数f(x)的周期性问题,证明了下列有意义的结果P(f)=∩ P(f-1(a));同时给出a∈v(f)了若干重要的推论.  相似文献   

5.
令 P(f ) ={t∈ R| x∈ D有 x± t∈ D且 f (x +t) =f (x) },V(f ) ={f (x) |x∈ D}.本文主要探讨利用 P(f )度量函数 f (x)的周期性问题 ,证明了下列有意义的结果 :P(f ) =∩a∈ V( f) P(f- 1 (a) ) ;同时给出了若干重要的推论 .  相似文献   

6.
本文讨论了下面的Neumann边值问题{-△u=f(x,u)x∈Ω Dru=g(x,u)x∈эΩ 这里Ω是R^N的有界光滑区域,эΩ是C^1类的,证明了在f(x,u)、g(x,u)满足一定的条件下该方程正解的存在性。  相似文献   

7.
设f:G→G是群G的自同态,满足f(x)=xn(?x∈G),证明了G是交换群当且仅当n=-1或2;设M={n|f:G→G是群G的自同态,满足f( x)=xn ,?x∈G},证明了G是交换群当且仅当n遍历M中所有元时,所有形如n( n-1)元的最大公因数为2.  相似文献   

8.
本文通过函数f(x)=■定义了一个函数列入fn(x)n}n∈N,并讨论了{fn(x)}n∈N的解析表示和周期性.  相似文献   

9.
主要讨论迭代方程f(ax+f(x))=h(f(x)),a≠0,x∈R的实连续解的存在性、连续依赖性和对称性,并根据对称性将一些结果推进到高维。  相似文献   

10.
文章给出了f(x)∈C2m^1时,Abel—Poisson型奇异积分的导数P’r(f;x)逼近f'(x)时的逼近阶,并改进了文献[2]的结果.  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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