整数分解式的指数函数及其均值的计算

给出了整数标准分解式的数论函数β(n，p)和它的均值∑n≤Nβ(n，p)的定义，推出了整数n标准分解式的指数函数计算公式和均值∑n≤Nβ(n,p)的精确计算公式．     

关于n进制及其有关计数函数

给出了n进制中数字之和函数均值A（N）的一个精确的计算公式。     

一类矩阵的Drazin逆

本得到了一类环上矩阵Drazin的一个定理：设N表有单位元环R中零元、可逆元集合与R的中心Z(R)的交集，M表R的子域与Z（R)的交集，A∈Rn×n，若f(λ)=cλ(1-λq(λ))是A的化零多项式，其中q(λ)的系数属于N，且c∈N，则A的Drazin逆存在，且X=A^k[q(A)]k 1是A的唯一的一个Drazin逆。     

H-矩阵的实用判定及谱分布

1引言及记号因为非奇异H-矩阵主对角元非零,所以本文总假定所涉及矩阵主对角元非零,并且设A=(aij)∈Cn×n为n阶复方阵,N={1,2,…,n}．记N1={i∈N |Pi(A)<|aii|Pi(A)}, N4={i∈N | |aii|≥Pi(A)>Ri(A)}, N5={i∈N | |aii|>Pi(A)=Ri(A)},N0={i∈N | |aii|≤Ri(A),|aii|≤Pi(A)},即N=N1∪N2∪N3∪N4∪N5∪N0．     

(高一)函数自测题(二)

一、选择题化简(。导b告)(一3·告b专)、(专·含b甘)的结果(A)6a(B)一a(C)一ga(D)(〕a匕2.设函数y一19(二之一5‘:)的定义域为M，函数y一馆(‘:一5) lgx的定义域为N，则(). (A)MUN~R(B)M卫N (C)M=N(I〕)M里N 3.下列函数中既是偶函数又在(一~，O)_上几是增函数的是(). (A)y一rZ     

复旦大学1984年硕士研究生入学考试试题

3.A是m×n实矩阵,N(A)表示所有满足Ax=0的n维向量x所构成的线性子间,dim N(A)记N(A)的维数,记 r(A)是A的秩,证明     

套代数上的广义Jordan中心化子

设H是实数域或复数域F上的Hilbert空间,N为H上的非平凡套,τ(N)为相应的套代数,并且φ:τ(N)→τ(N)是一个可加映射.本文证明了如果存在正整数m,n,p,使得(m+n)φ(A~(p+1))=mφ(A)A~p+nA~pφ(A)或φ(A~(m+n+1))=A~mφ(A)A~n对所有的A∈τ(N)成立,则存在λ∈F,使得对所有的A∈τ(N),有φ(A)=λA.     

p—除环上矩阵秩的恒等式

本文证明了[1]中的猜测:在p—除环上有恒等式r(?)=r(A) r(B) ((I_s-BB~ )C(I_n-A~ A)),并且改进了这个结果,此外还给出了几个关于矩阵秩的恒等式.设Ω是p-除环,A是Ω上的m×n矩阵.μ(A)表示由A的行向量张成的Ω上的左向量空间,N(A)表示满足XA=0的行向量张成的Ω上的左向量空间,则μ(A)(?)Ω,N(A)(?)Ω_m,μ(A)、N(A)、Ω_m、Ω_n都是左Ω—模,并且dim N(A)=m-r(A).引理1 A、B、C分别是Ω上的m×n、m×s和s×n矩阵,那么     

On the values of representation functions

For a set A of nonnegative integers, the representation functions R2(A,n) and R3(A,n) are defined as the numbers of solutions to the equation n = a + a′ with a,a′∈ A, a < a′ and a a′, respectively. Let N be the set of nonnegative integers. Given n0 > 0, it is known that there exist A,A′■ N such that R2(A′,n) = R2(N \ A′,n) and R3(A,n) = R3(N \ A,n) for all n n0. We obtain several related results. For example, we prove that: If A ■ N such that R3(A,n) = R3(N \ A,n) for all n n0, then (1) for any n n0 we have...     

Smarandache幂函数的均值

对于给定的自然数n,Smarandache幂函数SP(n)定义为SP(n)=min{m: n|mm,m∈N}．本文研究了这个函数的均值分布性质,并利用解析方法得到了Smarandache幂函数的一个较强的均值公式．     

First observations of the water masers with the Urumqi 25m radio telescope

A new radio spectral receiving system has been installed on the 25 m radio telescope of the Urumqi Astronomical Observatory. The back end is a surface acoustic wave chirp transform spectrometer (SAW CZT), used for the first time in radio astronomy. The calibration of the line observations has carefully been investigated for the new-type spectrometer. In order to test the feasibility of the prototype spectrometer, we observed water maser emission from a number of known Galactic sources. We describe the observed spectra of W49N, W3(OH), 2248 + 600 and 1909 + 090. We found that W49N spectrum showed high-velocity features ranging from −330 to 146 km s⁻¹. In comparison with the spectra observed by Medicina, the feature at the LSR velocity −52 km s⁻¹ in the W3(OH) presented the rapid variation in flux density.     

椭圆曲线y2=2px(x2+1)上正整数点的个数

设p是奇素数,N(p)是椭圆曲线E:y2=2px(x2+1)的正整数点(x,y)的个数.主要讨论了N(p)的性质,运用初等方法及四次Diophantine方程的性质,对某些特殊素数p,给出了N(p)的上界.证明了当p≡1(mod 8)且p=s2+32t,其中s,t是正整数时,N(p)≤3;当p≡1(mod 8)且p+s...     

弱闭T(N)-模的预零化子的等距映射

本文刻划了弱闭T(N)-模的预零化子间的等距映射.设u,W分别为由左连续序同态N→~N和N→~N所确定的弱闭T(N)-模, u(?),W(?)分别为u,W的预零化子,Φ为由u(?)到W(?)上的线性等距映射.若(0)*=(0)#=(0),dim(0)+≠1且min{dim(H(?)~H),dim(He(?)^H)}≥2,则存在酉算子Ui,Vi(i=1,2),使得Φ(A)=U1AV*1或Φ(A)=U2A*V2*.     

The dam problem in unbounded domains

Summary The time dependent dam problem in a general unbounded domain is studied and an existence theorem is proved by means of a rather general approximation procedure. Moreover the propagation of the support of the solution is studied in a number of geometrical situations of interest. The corresponding stationary problem is also studied and an existence theorem is proved. Finally several one-dimensional examples are given in which the solution can be either written explicitely or found solving an ordinary differential equation.This work has been supported by MURST (Italy), by I.A.N.-C.N.R. of Pavia (Italy), and by SFB 123 of University of Heidelberg (Germany).     

ON LOCAL CONTINUITY MODULI FOR GAUSSIAN PROCESSES

ＬＵＣＨＵＡＮＲＯＮＧ（陆传荣）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＨａｎｇｚｈｏｕＵｎｉｖｅｒｓｉｔｙ，Ｈａｎｇｚｈｏｕ３１００２８，Ｃｈｉｎａ）（ＴｈｉｓｗｏｒｋｉｓｓｕｐｐｏｒｔｅｄｂｙｔｈｅＮａｔｉｏｎａｌＮａｔｕｒａｌＳｃｉｅ...     

非线性中立型时滞方程解的全局渐近稳定性和振动性

本文研究非线性中立型时滞微分方程N( t) =N( t) [a( t) -b( t) N ( t-τ) -c( t) N( t-σ) -d( t) N ( t) ],t≥ t0 ,( E)其中τ,σ∈ [0 ,∞ ) ,a( t) ,b( t) ,d( t)∈ C1( [t0 ,∞ ) ,R+) ,c( t)∈ C( [t0 ,∞ ) ,k) ,得到方程 ( E)的正解关于正常数平衡点全局渐近稳定和振动的充分条件 .本文所用方法与其他文献不同 ,所得结果发展了一些文献的结果 ,其中定理 ( 2 .3)回答了由 Y.Kuang and A.Feldstein所提出的一个公开问题 .     

A Counterexample to a Uniqueness Result

A counterexample is given to the uniqueness result given in the article by Cox and Thompson (1970), "Note on the uniqueness of the solution of an equation of interest in inverse scattering problem." J. Math. Phys ., 11 , N3, 815-817.     

具结构阻尼的拟线性膜方程的吸引子及其上半连续性

本文研究具结构阻尼的拟线性膜方程utt+Δ²u+(-Δ)^αut+Δφ(Δu)+f(u)=g的适定性以及解的长时间动力学行为,其中α∈(1,2),旨在研究耗散指标α对方程解的适定性和长时间动力学行为的影响.本文证明非线性项φ(s)存在一个依赖于耗散指标α的临界指数pα=(N+4(α-1))/(N-4(α-1))⁺(N=3,4),当1≤pα时,对f(u)没有任何多项式增长限制:(ⅰ)方程的初边值问题是适定的,其解当t> 0时具有整体正则性;(ⅱ)对任意α∈(1,2),对应的解算子半群S^α(t)在自然能量空间中存在整体吸引子和指数吸引子;(ⅲ)整体吸引子族{Aα}在任意点α0∈(1,2)处上半连续,即对Aα0。的任意邻域U,当|α-α0|<<1时有Aα■U.