全平面上的随机Dirichlet级数的值分布

对于无限级随机Dirichlet级数几乎每一条水平线都是无限级无例外小函数的强Borel线.     

关于无穷级代数体函数Borel方向的定理

本文研究了无穷级代数体函数Borel方向的判定问题.利用代数体函数的一个基本不等式,获得了一个关于无穷级代数体函数Borel方向的判定定理,将李国平关于无穷级半纯函数的聚值线判定定理推广到了无穷级代数体函数.     

ALMOST SURE AND QUASI-SURE GROWTH OF DIRICHLET SERIES

GivenaDirichletseriesabsolutelyconvergentintherighthalfplanewecanclassifyitsgrowthaccordingtotheRittorder(order(R))[4,5].Multiplyingthetermsofthisseriesbymembersofsomesequencewefindthattheseriesobtainedisofthesameorder(R)oncountablymanyhorizoata1halflinesinthishalfplane.Bymeansofsomeprobabilityortopologicalspaceswecanconstructsequenceshavingtheabovepropertyandintroducethusalmostsureandquasi-suregrowthofDirichletseriesonhorizontalhalfline8.TheseresultscanbeextendedtoDirichletseriesabsolutelyc…     

On the definition of baer subplanes of infinite planes

LetP be an infinite projective plane and letB be a subplane ofP. An example is given which shows that the following two conditions are independent: (1) Every line ofP is incident with at least one point ofB. (2) Every point ofP is incident with at least one line ofB.This research was supported by the C.N.R. (Italy).     

无限级Dirichlet级数

本文研究了右半平面上无限级的Ｄｉｒｉｃｈｌｅｔ级数及随机Ｄｉｒｉｃｈｌｅｔ级数．这里我们给出一个较宽的系数条件,并证明在一定意义上是最好的;计算无限级Ｄｉｒｉｃｈｌｅｔ级数的精确级;把随机级数的研究引向一般得多的非同分布情况,并得到右半平面上非同分布的无限级随机Ｄｉｒｉｃｈｌｅｔ级数几乎必然（ａ．ｓ．）以虚轴上的每一点为没有有限例外值的Ｂｏｒｅｌ点的结论．     

Hölder continuous solutions for second order integro-differential equations in banach spaces

We study Hlder continuous solutions for the second order integro-differential equations with infinite delay （P1）: u′′（t）+cu′（t）+∫t-∞β（t-s）u′（s）ds+∫t-∞γ（t-s）u（s）ds = Au（t）-∫t-∞δ（t-s）Au（s）ds + f（t）on the line R, where 0 < α < 1, A is a closed operator in a complex Banach space X, c ∈ C is a constant, f ∈ C^α（R,X） and β,γ,δ∈L¹（R+）.Under suitable assumptions on the kernels β, γ and δ, we completely characterize the C^α- well-posedness of （P₁） by using operator-valued C^α-Fourier multipliers.     

无限级Dirichlet级数及随机Dirichlet级数

主要研究全平面上无限级Ｄｉｒｉｃｈｌｅｔ级数及随机Ｄｉｒｉｃｈｌｅｔ级数的增长性．对于 Ｄｉｒｉｃｈｌｅｔ级数,研究了它的增长性和正则增长性,得到了它的系数和指数与增长级的两 个充要条件．对于随机Ｄｉｒｉｃｈｌｅｔ级数,证明了它的增长性几乎必然与其在每条水平直线 上的增长性相同．     

整数环上一类二阶矩阵方程的解

设A是一个m×m可逆矩阵,称使得An=kE(E为单位矩阵)对某个实数k成立的最小正整数n为A的阶,记为O(A).本文证明,在整数环上,2×2矩阵方程An=kE(det(A)≠0)有解当且仅当矩阵A的阶O(A)∈{1,2,3,4,6}.     

On the small-time local controllability of a quantum particle in a moving one-dimensional infinite square potential well

We consider a quantum charged particle in a one-dimensional infinite square potential well moving along a line. We control the acceleration of the potential well. The local controllability in large time of this nonlinear control system along the ground state trajectory has been proved recently. We prove that this local controllability does not hold in small time, even if the Schrödinger equation has an infinite speed of propagation. To cite this article: J.-M. Coron, C. R. Acad. Sci. Paris, Ser. I 342 (2006).     

Prime divisors of second order linear recurrences. II

It is shown that, on average but independent of any hypothesis, the density of prime divisors of an infinite set of second order linear recurrences is greater than 0. It is also proved that the rough estimate, suggested by R. R. Laxton, for calculating this density is true on average.     

Surjectivity of Linear Differential Operators in a Weighted Space of Infinitely Differentiable Functions

We present a sufficient condition for the surjectivity of a linear differential operator of infinite order with constant coefficients in a weighted space of infinitely differentiable functions on the real line.     

关于循环环的理想、素理想和极大理想

研究了循环环R=的理想、素理想和极大理想的个数和结构,得到了如下结论:1)理想:(1)若|R|=∞,则R共有无穷多个理想:;(2)若|R|=n,设n的正因数个数为T(n),则R共有T(n)个理想:.2)素理想:(1)若|R|=∞,设a^2=ka(k≥0),①当k=0时,R的素理想只有R;②当k>0时,R的素理想共有无穷多个,它们是:{0}、R及;(2)若|R|=n>1,设a^2=ka,0≤k.3)极大理想:(1)若|R|=∞,则R有无限多个极大理想,它们是;(2)若|R|=n>1,设n的互不相同的素因数个数为ψ(n),则R共有ψ(n)个极大理想:(pa|p是n的素因数).     

Self Extending Rings

A ring R is an IPQ (isomorphic proper quotient)-ring if R ? R/A for every proper ideal A ? R. If every ideal A ? R satisfies: either R ? A or R ? R/A, then R is called an SE (self extending)-ring. It is shown that with one exception, an abelian group G is the additive group of an IPQ-ring if and only if G is the additive group of an SE-ring. The one exception is the infinite cyclic group Z. The zeroring with additive group Z is an SE-ring, but a ring with infinite cyclic additive group is not an IPQ-ring. Since the structure of the additive groups of IPQ-rings is known, the structure of the additive groups of SE-rings is completely determined.     

ON THE DISTRIBUTION OF VALUES OF RANDOM DIRICHLET SERIES(II)

For certain Dirichlet series almost surely(a.s.)of order(R) ρ∈(0,∞)in the right-halfplane,a.s.every point of the imaginary axis is a Borel point of order ρ+1 and with no finiteexoeptional value.     

Multiple Positive Solutions for First Order Impulsive Singular Integro-Differential Equations on the Half Line

In this paper, the author discusses the multiple positive solutions for an infinite boundary value problem of first order impulsive singular integro-differential equations on the half line by means of the fixed point theorem of cone expansion and compression with norm type.     

Multiple positive solutions for first order impulsive superlinear integro-differential equations on the half line

In this paper, the author discusses the multiple positive solutions for an infinite boundary value problem of first order impulsive superlinear integro-differential equations on the half line by means of the fixed point theorem of cone expansion and compression with norm type.     

关于复方程f″+Af=0的解的一个结果

设f1,f2为f″+A f=0(其中A是一个超越整函数)的两个线性无关解.令E=f1f2并且假设E的级λ=∞和E的下级μ<∞.则对任意的ρ>0,E有无穷条ρ级零点聚值线。     

Average B-width and infinite dimensional G-width of some smooth function classes on the line

In this paper, we get the exact values of average σ-B width and infinite dimensional σ-G width of Sobolev class B^r _p(R) in the metric L_p(R) (1≤p≤∞) and obtain the exact (σ∈N) and strong asymptotic (σ>1) results of infinite dimensional σ-G widths of Sobolev-Wiener class W^r _pq (R) in the metric L_q(R) and its dual case W^r _p(R) in the metric L_qp(R) (1≤q≤p≤∞).     

Zur theorie rotierender und schwingender schaufelkränze in einer unterschallstromung durch einen ringkanal

In this paper the three-dimensional perturbation flow induced by a rotating and oscillating blade row which operates in a subsonic flow in axial direction of an annular channel is studied. The velocity potential is reduced to the infinite Hilbert space vector of Fourier coefficients of an eigen-function expansion with respect to vanishing normal derivatives on both cylinder walls. These coefficients satisfy an infinite set of ordinary differential equations of second order after an application of a one-dimensional Fourier transform in axial direction. Several canonical two-part mixed boundary value problems are then investigated by reduction to “infinite two-by-two-Wiener-Hopf functional systems”. In case of strong factorizability of certain matrix-operator-valued functions on the line these systems may be solved explicitely. Criteria for the factorization are not given here.     

模型论在代数上的应用

给出了模型论在代数上的两个应用,得到了下列定理：定理A：如环R的任何有限生成子环均是局部环,则R是局部环.定理B：存在自然数的真扩张R使其具有下列特征：（1）虽然R有无限多零因子,但R中有无限多零因子,但R中的首1多项式的根的个数可以得到很好的控制.（2）R不仅将自然数的素数特征保留下来,而且还可在其上定义指数函数。