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1.
引入强优美树概念,证明了三星体R_[(n-p),n,n+p](n为自然数;p=1.2)是强优美树,从而得到四星体R_[(n-p),n,n+p,m](m,n为自然数;p=1,2)是优美树的结果。  相似文献   

2.
证明了森或树的任一正特征值λq-i(i=q-1,q-2,…,0)满足λq-i≥2cos[tiπ/(2ti+1)](ti=[[2q/(i+1)]/2]),并指出这个下界对于边独立数为q的森或者顶点数为n、边独立数为q的森是最好可能的;对于边独立数为q的树或者顶点数为n、边独立数为q的树当i=q-2,q-3,…,q-[(q+1)/2]或当i=q-[(q+1)/2]-1,q-[(q+1)/2]-2,…,1(q0(modi+1))时,这个下界是最好可能的  相似文献   

3.
研究了势型算子TΦf(x)=∫Rn^Φ(x-y)f(y)dy在LV^p(R^n)到Lω^q(R^n)上有界的充分条件,当1≤p≤q〈∞,1〈r〈ps/p+s-1,s〉1,Φ(x)是非负函数,且Φ∈Lloc^1(R^n),Φ(t)=(∫/z/≤t^Φr(z)dz)^1/r。若对任何方体Q有Φ(l(Q))/Q/^、/q-1/p+1/r(1//q//∫Q^W^qsdx)^1/qs(1//Q/∫Q^v-p  相似文献   

4.
对高斯函数的两个恒等式:〔x〕+〔x+1/m〕+...+〔x+m-1/m〕=〔mx〕,其中x∈R,m∈N;1/2(p-1)Σ(k=1)〔kq/p〕=P-1/2.q-1/2,其中p、q是正奇数且(p,q)=1,以及Tom.M.Apostol的一个问题“若a=1,2,3,4,5,6,7。证明存在一个(依赖于a的)整数b,使得nΣ(k=1)〔k/8〕=〔(2n+b)^2/8a〕”,作了进一步的推广,得到  相似文献   

5.
本文提出了在垂直照射由二个无色散介质所构成的反射界面的情况下,正弦调制的调频波产生合成驻波的条件:和这个条件在令时,根据不同的p+q值(奇数或偶数)所呈现的不同形式: 1.p+ q=奇数, 2. p+ q=偶数=2 a,还给出了反射系数相角与反射界面至相邻合成驻波节的间距之间的关系: θ= 2βο[- x]h=ο-(2m+1)π, 0≤θ≤π。最后又作出了调频波产生这种合成驻波的物理解释。  相似文献   

6.
提出了正整数的真r-剖分的定义并利用它解决了1994 年F.Harary 在[3]中提出的一个未决问题,即确定完全二分图Kr,s的整和数和和数.得到如下结果:σ(Kr,s)= ζ(Kr,s)= sk+ r- 1,其中sr2,sk 是整数s的真r-剖分的最末项。此外,在这篇文章中我们还举例说明了N.Hartsfield和Sm yth 在[11]中给出的一个结论σ(Kr,s)= [(3r+ s- 2)/2]是错误的。  相似文献   

7.
本文证明了如果T是一个R-空间,f是一个积性函数,fT,f(n+B)-cf(n)∈T[n],其中B为正整数,c为复常数,那么必有c=±1,而且对于任何素数p皆有非负整数αp使f(pαp+r)(f(pαp))r-1=(f(pαp+1))r,r=2,3,….进一步,如果c=1或p≠2,则有pαp|B,而当c=-1时2α2|2B,推广了以前的结果  相似文献   

8.
设f(x)∈AC[0,H],产F(0)=f(h)=0,则有∫^h0|ff'|dx≤1/2(h/2)^2/Q(∫^h0|f'|^pdx)^2/p-2/q{|f'|^pdx)^2-1/4(∫^h0|f;|^pcos(2πx/h)dx)^2}^4/q其中1<p≤2,Q=P/(P-1).(2)显著比(1)优秀,实际上我国已证得更一般的结果。  相似文献   

9.
一类具有二阶细焦点的二次系统   总被引:2,自引:0,他引:2  
对如下一类具有二阶细焦点的二次系统进行了研究, dx/dt=-6+ax^2, dy/dt=x+lx^2+mxy+ny^2,其中w1=-2al-m(l+n)=0,w2=a(2a+m)(3a-m0[n(l+n)^2-a^2(al+n)]≠0。证明了当-1<l/n≤时,系统(1)在0外围  相似文献   

10.
证明了:对1≤s<r- 2,如果 q= 7· 2(r-2)+2s-1与p= 49· 2-5·2(r-s-2)-1均为素数,则为方程的解.通过在微机上的探索,对4≤r≤500,找到了方程的33组解.  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.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
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.  相似文献   

19.
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   

20.
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   

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