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1.
设φ(n)是 Euler函数 ,本文将渐近估计式 ∑n≤ xφ(n) =3π2 x2 +O(xlogx) (x >2 )进行了一系列推广 ,给出了∑n≤ xnαφ(n) ,∑n≤ x(-1 ) n- 1 nαφ(n) ,∑n≤ xp | nnαφ(n) ,∑n≤ xp | nnαφ(n)等和式的渐近估计式  相似文献   

2.
用一个单调函数ω(t) 为中介,利用Szasz-Durrmeyer算子导数的性质以及该算子的可换性和光滑模ωφλ(f,t)为特点,得到以下点态逼近逆定理对于f∈C[0,+∞),0≤λ≤1,φ(x)=x,δn(x)=φ(x)+1/n, 若|f(x)-Sn(f,x)|≤Mω(n-1/2δ1-λn(x)),其中ω(t)≥0, ω(ut)≤C(u2+1)ω(t),则对任意t>0,有ω2φλ(f,t)≤Ct2∑0<n≤t-1(n+1)ω(n-1)+Ct2‖f‖,ω1(f,t)≤Ct∑0<n≤t-1ω(n-(2-λ)/(2))+Ct‖f‖.此结果推广了有关ωφ(f,t)和ω(f,t)的结果.  相似文献   

3.
用一个单调函数ω(t)为中介 ,利用 Szász- Durrmeyer算子导数的性质以及该算子的可换性和光滑模ωφλ(f ,t)为特点 ,得到以下点态逼近逆定理 :对于 f∈ C[0 , ∞ ) ,0≤λ≤ 1,φ(x) =x ,δn(x) =φ(x) 1/ n ,若|f (x) - Sn(f ,x) |≤ Mω(n- 1 /2δ1 -λn (x) ) ,其中ω(t)≥ 0 , ω(ut)≤ C(u2 1)ω(t) ,则对任意 t>0 ,有ω2φλ(f ,t)≤ Ct2 ∑0 相似文献   

4.
F.Smarandache LCM函数SL(n)定义为使得n|[1,2,3,…,k]整除1,2,3,…,k的最小公倍数的最小正整数k.主要利用SL(n)的性质及Mangoldt函数∧(n)的定义研究了∧(n)·SL(n)的均值性质,并得到了渐近公式∑n≤x∧(n)SL(n))=X2∑ki=1Ci/㏑i-1x+O(x2/㏑kx).  相似文献   

5.
设 d(n)和σ(n)分别是除数函数和除数和函数 ,本文将渐近估计式 ∑n≤ xd(n) =xlogx +(2γ -1 ) x+O(x ) (x >2 )和渐近估计式 ∑n≤ xσ(n) =ζ(2 )2 x2 +O(xlogx) (x >2 )进行了一系列的推广 ,给出了∑n≤ xp | nd(n) ,∑n≤ xp | nd(n) ,∑n≤ x(-1 ) n- 1 d(n) ,∑n≤ xp | nσ(n) ,∑n≤ xp | nσ(n) ,∑n≤ x(-1 ) n- 1 σ(n)等和式的渐近估计式 .  相似文献   

6.
讨论了有关Euler函数φ(n)的四元变系数混合方程φ(xyzω)= 3φ(x)φ(y)+5φ(z)φ(ω)的正整数解,利用Euler函数φ(n)的计算公式以及初等方法,得到该方程有372组正整数解,并给出其满足x≤y,z≤ω的93组正整数解.  相似文献   

7.
在一定条件下,得到了φ混合样本条件t分位数的核估计强收敛速度,即定理 对同分布的φ混合样本(X1,Y1),…,(Xn,Yn)∈Rd×R1,若 X1具有边际密度函数f; 条件分布函数F(y|x)在(x,θx(t))的邻域内具有连续的密度函数f(y|x); ∑nφ(n)<∞; h=(n-12logn)1d 1,0相似文献   

8.
一类具有转向点超曲面的奇摄动椭圆型方程边值问题   总被引:7,自引:0,他引:7  
讨论了n维空间中如下一类具有转向点超曲面的奇摄动椭圆型方程的边值问题Lεu≡εLu ∑^ni=1fi(x1,……,xn)Эu/Эxi g(x1,……,xn)u=0,(x1,……,xn)∈Ω,u(x1,……,xn)│ЭΩ1=φ1(x1,……,xn-1),ai≤xi≤bi,u(x1,……,xn)│ЭΩ2=φ2(x1,……,xn-1),ai≤xi≤bi。其中:ε为一正参数,且L=∑ni,j=1aij(x1,……,xn)Э^2/ЭxiЭxj(aij=aji),∑ni,j=1aijξiξj≥λ∑ni=1ξ^2i,任意ξi∈R,i=1,2,……,n,λ>0。利用多重尺度法和比较定理、就形坐标和抛物柱函数,研究了该边值问题解的渐近性态。  相似文献   

9.
借助于优超理论,在适当的假设下建立了如下的Jensen-Pe(c)ari(c)-Svrtan型不等式f(A(x))/f(A(φx))=fn,n(x)/fn,n(φx)≤(≥)...≤(≥)fk+1,n(x)/fk+1,n(φx)≤(≥)fk,n(x)/fk,n(φx)≤(≥)...≤(≥)f1,n(x)/f1,n(φx)=A(f(x))/A(f(φx)),这里,A(·)表示算术平均,φ:[a,b]→R, f:[a,maxt∈[a,b]{φ(t)}]→R, fk,n(x):=1/(nk)∑1≤i1<...<ik≤nf(xi1+xi2+...+xik/k), x∈[a,b]n.  相似文献   

10.
设Ψ (n)是 Dedekind函数 .以 E(x)表示和式 ∑n≤ xΨ (n)n 的渐近公式中的误差项 ,本文研究了 E(x)的加权平方积分均值 .  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

18.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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