奇数阶边值问题正解的存在性与多重性

利用锥拉伸锥压缩不动点定理,证明了在一定条件下,下列非线性奇数阶方程(-1)q+1u(2q+1)(t)=λa(t)f(u(t)),0 t 1,(-1)q+1u(2q+1)(t)=λa(t)f(u(t)),0 t 1,u(0)=u′(τ)=u″(1)=0u(2j+1)(0)=u(2j+1)(1)=0,j=1,2,…,q-1.单个和多个正解的存在性,其中λ>0,12<τ<1,q∈N.得到了λ的区间Λ,对一切λ∈Λ,该问题至少有一个正解,同样也得到了该问题至少有两个正解λ相应的区间.     

Interval maps from Cuntz-Krieger algebras

Markov interval maps f naturally produce transition aperiodic 0-1 matrices with extra features. We characterize the 0-1 matrices that can be realized as Markov transition matrices of interval maps, and parametrize the orbit representations (yielded in Correia Ramos et al. (2008) [2]) of the Cuntz-Krieger algebra OA obtained from interval maps with the same matrix A.     

参数边界条件下奇型Sturm-Liouville算子的半逆问题

Sturm-Liouville算子的半逆问题讨论由一组谱和半区间上势函数唯一确定整个区间上势函数q(x).本文利用Koyunbakan和Panakhov的方法和[13]的结论,讨论(0,π)上的奇型Sturm-Liouville问题满足-y″+[q(x)-1/4sin2x]y=λy,参数边界条件y(0,λ)=0或y′(0,λ)-hy(0,λ)=0和y′(π,λ)+(aλ+b)y(π,λ)=0,证明一组谱和(π/2,π)上的势函数q(x)唯一确定(0,π)上的势函数q(x).     

當若阿-富理埃級數的係數

<正> 不能用蔡查羅(Cesaro)的平均法求它的和;這是哈戴和立篤耳武德老早指出過的,他們的解析是依靠着(?)函數的理論。 其後,鐵起馬虛用初等的方法作成如下的實例:     

迭代逼近m-增生映象的零点

设E是具有一致正规结构的实Banach空间,其范数是一致Gateaux可微的.设A是m-增生映象,使得C=■是E的凸子集,数列{α_n)■[0,1],{r_n}■ (0,∞),在适当的条件下,则由(1.2)式定义的迭代序列{x_n}强收敛于A~(-1)(0)中的点.其次证明了:设E是一致凸Banach空间,其范数是Frechet可微的.设数列{α_n},{β_n)■(0,1),{r_n}■(0,∞),满足适当的条件.如果A~(-1)(0)∩B~(-1)(0)≠φ,则由(3.20)式定义的序列{x_n}弱收敛于A~(-1)(0)∩B~(-1)(0)中的点.其结果推广和改进了Kamimura,Takahashi(2000)的定理2及Xu H.K.(2006)的定理4.1,定理4.2和定理4.3:(i)Kamimura,Takahashi(2000)定理2中的假设"自反Banach空间E的每个有界闭凸子集对非扩张自映象有不动点性质"被去掉;(ii)Xu H.K.(2006)的假设"E是具有弱连续对偶映象J_φ的自反Banach空间",被本文的假设"E是具有一致正规结构且其范数是一致Gateaux可微的Banach空间"所取代.从而补充了Xu H.K.(2006)未包含的另外一些Banach空间.同时还证明了逼近两个m-增生映象的公共零点,其结果也推广和改进了Mainge的相应结果.     

单机上带有可变前瞻区间的分批在线排序问题

本文研究单台无界平行批处理机上带有可变前瞻区间的在线排序问题。工件按时在线到达,目标是最小化时间表长。在时刻$t$,在线算法能够预见到$（t,t+\Delta（t）]$内到达工件的信息,这里前瞻区间的长度$\Delta（t）=\beta p_{\max}（t）$并非定长,其中$p_{\max}（t）$表示在$t$时刻及之前到达工件的最大加工时长,$\beta\in（0,1）$是常数。本文对于工件加工时长的一般情形,给出了当 0<β≤1/6 时最好可能的在线算法;对于工件加工时长被限制在一个区间的情形,给出了当 0<β<1 时最好可能的在线算法。     

单机上带有可变前瞻区间的分批在线排序问题

本文研究单台无界平行批处理机上带有可变前瞻区间的在线排序问题。工件按时在线到达,目标是最小化时间表长。在时刻$t$,在线算法能够预见到$（t,t+\Delta（t）]$内到达工件的信息,这里前瞻区间的长度$\Delta（t）=\beta p_{\max}（t）$并非定长,其中$p_{\max}（t）$表示在$t$时刻及之前到达工件的最大加工时长,$\beta\in（0,1）$是常数。本文对于工件加工时长的一般情形,给出了当 0<β≤1/6 时最好可能的在线算法;对于工件加工时长被限制在一个区间的情形,给出了当 0<β<1 时最好可能的在线算法。     

带耗散项的浅水波方程的整体边界稳定性

在[0,1]区间上研究带耗散项的浅水波方程由边界反馈引起的整体指数稳定性.在控制边界条件u(0)=u_x(1)=u_(xx)(0)=δu_(xxx)(1)-εu(1)u_(xx)(1)-(?)(u(1))=0之下,证明了解的H1整体指数稳定性和H4整体渐进稳定性.     

LP[0,1](1＜p＜∞)空间正系数多项式倒数逼近的一个推广

本文推广了LP[0,1](1＜p＜∞)空间函数的正系数多项式的倒数逼近的结论,即证明了:设f(x)∈LP[0,1],1＜p＜∞,且在(0,1)内严格1次变号,则存在一点x0∈(0,1)及一个n次多项式Pn(x)∈∏n(+)使得‖f(x)-x-x0/Pn(x)‖LP[0,1]≤Cpω(f,n-1/2)LP[0,1],其中∏n(+)为次数不超过n的正系数多项式的全体.     

On eigenfunction expansions for a nonlinear Sturm-Liouville operator with spectral-parameter dependent boundary conditions

We study a nonlinear eigenvalue problem for a Sturm-Liouville operator on the interval (0, 1). The boundary conditions posed at both endpoints of the interval depend on the spectral parameter. We prove that the problem has an eigenfunction system that is a basis in the space L _p (0, 1) for p > 1 and a Riesz basis for p = 2.     

一类三阶拟线性微分方程非振动解的渐近性

主要讨论的是一类三阶拟线性微分方程(p(t)|u″|~(α-1)u″)′+q(t)|u|~(β-1)u=0其中α0,β0,p(t)和q(t)是定义在区间[a,∞)上的连续函数,且满足当t≥a时p(t)0,q(t)0.当t→∞时此方程满足∫_a~∞1/((p(t))~(1/α))dt=∞的特殊非振动解存在的充分必要条件.     

用黎曼求和法(R,1)求和時的基卜斯現象

<正> 假設級數滿足下面兩個條件,即:(甲)在原點的某一鄰域內,對於h(≠0)的一切值級數收斂;     

A maximal zero-free interval for chromatic polynomials of bipartite planar graphs

It is well known that (-∞,0) and (0,1) are two maximal zero-free intervals for all chromatic polynomials. Jackson [A zero-free interval for chromatic polynomials of graphs, Combin. Probab. Comput. 2 (1993), 325-336] discovered that is another maximal zero-free interval for all chromatic polynomials. In this note, we show that is actually a maximal zero-free interval for the chromatic polynomials of bipartite planar graphs.     

Complexity of approximate realizations of Lipschitz functions by schemes in continuous bases

We show that any function satisfying the Lipschitz condition on a given closed interval can be approximately computed by a scheme (nonbranching program) in the basis composed of functions $$x - y, \left| x \right|, x*y = \min (\max (x,0),1)\min (\max (y,0),1),$$ and all constants from the closed interval [0, 1]; here the complexity of the scheme is $O\left( {{1 \mathord{\left/ {\vphantom {1 {\sqrt \varepsilon }}} \right. \kern-0em} {\sqrt \varepsilon }}} \right)$ , where ? is the accuracy of the approximation. This estimate of complexity, is in general, order-sharp.     

Eigenvalues and the One-Dimensional p-Laplacian

We consider the boundary value problem (?_p(u′))′ + λF(t, u) = 0, with p > 1, t ∈ (0, 1), u(0) = u(1) = 0, and with λ > 0. The value of λ is chosen so that the boundary value problem has a positive solution. In addition, we derive an explicit interval for λ such that, for any λ in this interval, the existence of a positive solution to the boundary value problem is guaranteed. In addition, the existence of two positive solutions for λ in an appropriate interval is also discussed.     

Exact estimates for integrals related to dirichlet series

First, we consider integrals of the form $$\int {a(x)m^{ - x} dx for} m = 2,3,...$$ over the unit interval (0, 1) or the interval (1, ∞) or the half-line (0, ∞), wherea(x)≥0 and is integrable on the interval in question. These integrals are related to the Dirichlet series $$\sum\limits_{m = 2}^\infty {a_m m^{ - x} for x > 1} ,$$ , where the numbersa _m ≥0. We survey certain known results in a new formulation in order to reveal the difference in behavior between the functions which are integrable on either (0, 1) or (1, ∞). Their proofs can be read out from the existing literature. Second, we extend these results from single to double related integrals, while making distinction among the functionsa(x, y) which are integrable on either (0, 1)² or (0, 1)×(1, ∞) or (1, ∞)×(0, 1) or (1, ∞)². The case wherea(x, y) is integrable on (0, ∞)² is also included.     

On the combinatorics of Galois numbers

We define interval decompositions of the lattice of subspaces of a finite-dimensional vector space. We show that such a decomposition exists if and only if there exists a family of linear forms with certain properties. As applications we prove that all finite-dimensional real vector spaces admit an interval decomposition, while GF(2)ⁿ has an interval decomposition if and only if n≤4. On the other hand, we present an interval decomposition of GF(3)⁵. This partially answers a question of Faigle and Kruse (2004) [1] and [4].     

Jump boundary-value problem on a contour with elongate singularities

Let Γ be image of interval (0, 1) under one-to-one continuous mapping φ: (0, 1) → C. If closure of Γ differs from the set Γ bymore than two points, then we call Γ the contour with elongate singularities.We study boundary-value jump problems for analytical functions on that contours, and obtain new criteria for their solvability.     

A Sturmian separation theorem for symplectic difference systems

We establish a Sturmian separation theorem for conjoined bases of 2n-dimensional symplectic difference systems. In particular, we show that the existence of a conjoined basis without focal points in a discrete interval (0,N+1] implies that any other conjoined basis has at most n focal points (counting multiplicities) in this interval.     

论数论函数ψ(n),σ(n)及d(n)的一些性质

<正> 命 f(n)为一数论函数.关于函数比值(?)的分布问题,Soma-yajulu,Sierpi(?)ski 及 Schinzel 曾用算术的方法,对于ω(n),σ(n)及 d(n)加以处理.华罗庚教授首先指出用 Brun 节法处理这一类问题的途径.按这一方向,作者与