电子书与数字化图书馆的融合研究

论述了信息载体的变革对人类的重要意义,揭示了电子书和信息化图书馆的发展趋势和特点,指出了电子书与数字化图书馆结合的必然性和诸多优点.     

约束条件下增长曲线模型中回归系数线性估计的泛可容许性

该文讨论了增长曲线模型$Y=X_{1}BX_{2}+\epsilon$在约束条件$X_{2}'B'X_{1}'NX_{1}BX_{2}\leq\Sigma$下回归系数线性估计$DYF$的泛可容许性问题,在损失函数$(d(Y)-KBL)'(d(Y)-KBL)$下,给出了回归系数的线性估计是泛可容许性的充要条件,其结果推广了文献中已有的结论.     

粘性依赖密度的Navier-Stokes方程组的不连续解

该文研究了一类粘性系数依赖于密度的一维可压缩Navier-Stokes方程组的自由边界问题. 对初始密度是不连续的情形,证明了其解的局部存在性和唯一性. 其结果说明：不论初始密度的振荡幅度有多大,在某个时间段$[0,T]$上,气体内部不会产生真空状态,气体和真空的分界也是以有限速度传播的.     

电子纸的过去、现在和未来

电子纸显示技术已经在越来越多的产品和设备上得到应用。从这项技术的现状出发,分析了阻碍其发展的因素,并对其前景作出了展望。     

Qualitative Analysis of Bifurcating Solutions in the Lengyel-Epstein Model

One of the most fundamental problems in theoretical biology is to explain the mechanisms by which patterns and forms are created in the＇living world. In his seminal paper ＂The Chemical Basis of Morphogenesis＂, Turing showed that a system of coupled reaction-diffusion equations can be used to describe patterns and forms in biological systems. However, the first experimental evidence to the Turing patterns was observed by De Kepper and her associates（1990） on the CIMA reaction in an open unstirred reactor, almost 40 years after Turing＇s prediction. Lengyel and Epstein characterized this famous experiment using a system of reaction-diffusion equations. The Lengyel-Epstein model is in the form as follows     

关于(m,n)-凝聚模与预包络

In this paper,let m,n be two fixed positive integers and M be a right R-module,we define (m,n)-M-flat modules and (m,n)-coherent modules.A right R-module F is called (m,n) M-flat if every homomorphism from an (n,m)-presented right R-module into F factors through a module in addM.A left S-module M is called an (m,n)-coherent module if MR is finitely presented,and for any (n,m)-presented right R-module K,Horn(K,M) is a finitely generated left S-module,where S = End(MR).We mainly characterize (m,n)-coherent modules in terms of preenvelopes (which are monomorphism or epimorphism) of modules.Some properties of (m,n)-coherent rings and coherent rings are obtained as corollaries.     

关于Hutton定理的一个注

It is proved in this paper that there is a bijectionψ from J ∪ J' to δ∪δ' which satisfies:(1)ч|J:(J,C)→4(δ,≤)is a frame isomorphism;(2)ч|J':(J',C)→(δ',≤)is a coframe isomorphism,where J is the ordinary topology on[0,1],δ is the ordinary L-topology on L-unit interval I(L),and L is a frame with an order-reversing involution.This result improves Theorem 3 in Hutton's paper.     

关于Smarandache LCM序列

For any positive integer n,let L(n)=[1,2,…,n] be the least common multiple of the integers from 1 to n.Let k be any positive integer.The main purpose of this paper is to study the asymptotic property of L(nk),and give some interesting relevant results.     

ON POLYA-SZEGO INEQUALITIES

This paper gives two new inequalities, which improve two Polya-Szego ＇s inequlities.