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1.
一类函数方程的摄动解   总被引:1,自引:1,他引:0  
利用摄动理论的直接展开法,研究方程εf(x)=g(x,ε)的摄动解,其中ε是正的小参数,根据退化方程的单根或重根可给出方程的根.  相似文献   

2.
运用扰动方法研究RN(N>4)上具有临界指标的重调和方程{Δ2u=uN+4/N-4+εg(χ,u),limu|x|→∞(x)=0,u∈D2,2(RN),χ∈RN非平凡解的存在性,其中ε为任意小常数,lim|x|→∞g(χ,u)=0.  相似文献   

3.
设Tn是Xn={1,2,…,n}上的全变换半群.Tm是Xm={1,2,…,m}上的全变换半群,本文刻画出当nm时,Tn到Tm的所有同态,且还得到Tm为Tn的同态像的条件.  相似文献   

4.
1938年李国平教授对于半纯函数的填充圆及Borel向的某些定理作了一种精密性的补充与改进;他首先改进了半纯函数的第二基础定理,然后用此定理为一种工具进而改进了方程f(z)=a在某环带内的根数的Milloux定理,从而得出结论:完全略去方程程f(z)=a之一切重根的重级或完全略去重级超过三的一切重根,关于半纯函数f(z)的填充圆及Borel向的一切定理仍是真确的。这一结果对于在此以前应用填充圆来处理半纯函数Borel向的存在的有关定理作了一精密而完备的补充。  相似文献   

5.
对方程f(x)=0根的存在性证明、唯一性证明及方程根的个数讨论等三个方面提出浅见.  相似文献   

6.
对线性算子T的n次幂Tn,讨论其零空间N(Tn)的维数α(Tn):=dim N(Tn)与n.α(T)的关系,证明了当T是上半-Fredholm算子时,α(Tn)=n.α(T)对一切自然数n成立当且仅当T是半正则的.  相似文献   

7.
由第一类Chebyshev多项式组成的行列式Tn(m,k,l)计算   总被引:1,自引:0,他引:1  
研究了由第一类Chebyshev多项式Tn(x)组成的特殊行列式Tn(m,k,l)的计算问题,证明了当m<n-1时,Tn(m,k,l)=0,当m=n-1当及m>n-1时,给出了一个计算Tn(m,k,l)值的公式.  相似文献   

8.
牛顿法,也称切线法,它的基本思想是将非线性方程f(x)=0逐步转化为线性方程来求解.牛顿法应用范围较广,可解代数方程和超越方程,也可解非线性方程组,既可求方程实根,也可求复根;既可求单根,也能求重根.牛顿法程序简单,其在单根附近具有二阶敛速,因此是近似根精确化的一种相当有效的方法.  相似文献   

9.
§1.预备知识齐次方程: a,b是有限数,核k(s,t)∈L_2[a,b]。記D(λ)为核k(s,t)的Fredholm分母。λ_0为D(λ)=0的m重根。因为  相似文献   

10.
在将方程变形时,所得方程与原方程有时等价有时不等价。究竟哪些变形使方程等价,哪些变形使方程不等价呢?这个问题在现有的参考书上已有所论述,但还不够系统和完善。这里我们将在实数范围内进一步讨论这个问题。先介绍几个概念。若方程f(x)=g(x)中f(x)、g(x) 都是一元初等函数,则称该方程为一元初等方程。若方程f(x)=g(x) (1) 的任一解都是方程F(x)=G(x) (2) 的解,反之,方程 (2) 的解也都是方程 (1) 的解,也就是说两方程的解集相同,则称它们为等价方程。若两方程不仅解集相同且每个重根的重数也都相同时,则称它们为严格等价方程。本文只讨论等价方程而不讨论严格等价方程。为叙述方便再作如下约定:下面所说方程是指一元初等方程;所说的函数是指一元初等  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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