表整数为两个互素的无平方因子数的和

设n为正整数,并且Q1(n)={a|1≤a≤n,(a,n)=1,a为无平方因子数}.给出了|Q1(n)|的渐进公式,并将其应用于二元一次方程中,证明了:当n≥1011时,存在互素的无平方因子数a和b,使得n=a b.     

表自然数为两个无平方因子数的和

设n为自然数,(?)为全体无平方因子数的集合,T(n)是满足n=n b的数对{a,b}的个数,其中a,b∈(?)。本文证明了T(n)=cnρ(n) O(n~(2/3)logn)这里c=multiply from p (1-2/p~2),ρ(n)=multiply from p~2/n (1 1/(p~2-2)·p为素数。     

关于Banach代数中伪Drazin逆的进一步结果

在条件ab=φ(ba)下,研究了ab与a+b的伪Drazin逆的表达式.其中,a,b是Banach代数A中的2个伪Drazin可逆的元素,φ是A上双射的centralizer.证明了:若a,b是伪Drazin可逆的且ab=φ(ba),则ab是伪Drazin可逆的且(ab)~=b~a~;a+b是伪Drazin可逆的,当且仅当aa~(a+b)是伪Drazin可逆的,当且仅当aa~(a+b)bb~是伪Drazin可逆的.此时,(a+b)~=(aa~(a+b))~+sum from n=0 to ∞φ-(n(n+1))/2(1)(b~)~(n+1)(-a)~n(1-aa~).     

利用Fisher函数解约束优化问题的广义梯度投影算法

通过引入一个辅助优化问题,将广义投影与罚函数技巧和F isher函数(a,b)=a2 b2-(a b),a,b∈En的特殊性质:a2 b2-(a b)=0 a≥0,b≥0,ab=0结合起来,给出处理非线性等式、不等式约束问题的广义梯度投影算法,并证明该算法是全局收敛的.该算法不仅保持文献[6]的优点,而且还扩大了初始点的选择范围.     

广义Fibonacci数列与广义黄金分割数

令a,b为任意固定正常数,并记δ=δ(a,b)=a+b/(a+b).考虑广义Fibonacci序列F{n}为:Fn=aF_(n-1)+bF_(n-2),n≥2,F0=F1=1.一个熟知的基本事实是:比值序列{F_n/F_(n+1)}收敛,且其极限g(a,b)恰为关于a,b的广义黄金分割数.在附加条件bδ2的情况下,给出这个基本结论的一个新的、内蕴的证明.同时,由此也得到广义黄金分割数g(a,b)的连分数表达.     

双环网的宽直径

宽直径是度量网络通信延迟和容错性能的重要指标,而环网是局域网中广泛应用的一种网络结构。根据环网的对称性和点传递性,用点不交的最短路径算法研究了一类双环网C(n;a,b)(其中a,b是n的非平凡因子且a,b互素)的k-宽直径,并得到如下结论:当n=ab时,d₄(C(n;a,b))≤La／2」+b-1;当n=2ab时,d₄(C(n;a,b))≤a+b-1;当n=abr,r>2时,d₄(C(n;a,b))≤(r-1)a+b-2。     

无平方因子数的上界估计

设k、m、n∈N,对于给定的正整数n∈N,若存在屯使得对任意m∈N,都有m^k n,则称n为无k次幂因子数．特别地,若k=2。则称n为无平方因子数．利用初等方法,研究无平方因子的性质,进一步的获得了第n个无平方因子数的一个上界估计,并给出了参考文献中的一个评注．     

有向双环网络的宽直径公式

给出了有向双环网络G(n;s1,s2)的宽直径公式,它由G(n;s1,s2)所确定的L-形瓦的4个参数a,b,p,q表示.令u=a-p,v=b-q,用D(G)与D2(G)分别表示G(n;s1,s2)的直径与宽直径,则(1)当u=1,v=1时,D2(G)=n-1.(2)当u>1,v>1时,D2(G)=D(G) 1=max{a b-p-1,a b-q-1}.(3)当u=1,v>1时,D2(G)=|b-1/v| a v-2.(4)当u>1,v=1时,D2(G)=|a-1/u| b u-2.     

无平方因子数倒数和问题的几个估计

无平方因子数是指没有大于1的平方数作为因子.对于平方因子数分布的研究,现在已经有了一些结果.设（a,s）=1,论文研究了形如∑n≤x,n无平方,n≡b（s）1/n和∑n≤x,n无平方,n≡b（s）1nn/n的估计,改进了已有结果的余项.     

左广义弱零插入环的一个问题

首先, 证明含单位元的结合环R是左广义弱零插入(GWZI)环当且仅当对任意的a,b∈R, ab=0蕴含存在正整数n, 使得aⁿRb=0; 其次, 利用矩阵分块方法证明环R是左GWZI环当且仅当对任意的整数n≥2, S_n(R)是左GWZI环.     

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.     

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。     

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

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     

Call for Papers

<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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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