命题公式集F(S)的基于R0-算子的16类分划

利用R₀-蕴涵算子对命题公式集F(S)进行分类,得出了F(S)的一个16类分划,并证明了这种分类关于非运算是同余分类.最后讨论了各类关于MP运算与HS运算的封闭性.     

自反Banach空间中C0-半群族的稳定性

主要讨论了自反Banach空间中一类C0-半群族{Th(t)}稳定性问题,证明了此类半群族{Th(t)}指数稳定与弱Lp-稳定是等价的.     

ARCH(0,1)系数中位无偏估计分布的渐近展开(英文)

This paper is concerned with the distributional properties of a median unbiased estimator of ARCH(0,1)coefficient.The exact distribution of the estimator can be easily derived,however its practical calculations are too heavy to implement, even though the middle range of sample sizes.Since the estimator is shown to have asymptotic normality,asymptotic expansions for the distribution and the percentiles of the estimator are derived as the refinements.Accuracies of expansion formulas are evaluated numerically,and the results of which show that we can effectively use the expansion as a fine approximation of the distribution with rapid calculations.Derived expansion are applied to testing hypothesis of stationarity,and an implementation for a real data set is illustrated.     

Banach空间中无限维线性系统的能控性

研究在非自反状态空间和自反控制空间中无限维线性系统x(t)=Ax(t) Bu(t)的精确能控性和精确零能控性.当A生成C-半群时,得到这个系统关于L~p([O,T],U),1相似文献   

集值映射空间在紧开拓扑下的N_0性质

本文讨论了点紧致的连续集值映射空间在赋予紧开拓扑下的某些拓扑性质,证明了:若X,Y为N_0空间,则X到Y上的点紧致的连续集值映射族依紧开拓扑是N_0空间,从而将Michael的结论推广到更大的映射空间类上.     

具有热储备的并行可修复系统指数稳定性分析

应用泛函分析的方法讨论了有两个相同部件和一个热储备的并行可修复系统的指数稳定性.我们通过分析系统算子生成C0半群的本质谱增长阶,证明了该半群是拟紧的.此外,该半群还是不可约的.于是作为半群拟紧性和不可约性的直接结果,得到了系统的时间依赖解指数收敛到其静态解,并且该静态解即为系统算子简单特征值0对应的正的特征向量.     

凝聚环和IF环

本文利用特征模，Ｎ０－内射维数对凝聚环给出了一些新的刻划．得到了凝聚环与ＩＦ环的一些有意义的性质．推广了引文［１］中的两个主要定理之一的定理２的结论．     

A new positive‐definite regularization of incompressible Navier–Stokes equations discretized with Q1/P0 finite element

A new regularization method is proposed for the Galerkin approximation of the incompressible Navier–Stokes equations with Q1/P0 element, by newly introducing a square‐type linear form into the variational divergence‐free constraint regularized with the global pressure jump (GPJ) method. The addition of the square‐type linear form is intended to eliminate the hydrostatic pressure mode appearing in confined flows, and to make the discretized matrix positive definite and then non‐singular without the pressure pegging trick. Effects of the free parameters for the regularization on the solutions are numerically examined with a 2‐D driven cavity flow problem. Furthermore, the convergences in the conjugate gradient iteration for the solution of the pressure Poisson equation are compared among the mixed method, the GPJ method and the present method for both leaky and non‐leaky 3‐D driven cavity flows. Finally, the non‐leaky 3‐D cavity flows at different Re numbers are solved to compare with the literature data and to demonstrate the accuracy of the proposed method. Copyright © 2003 John Wiley & Sons, Ltd.     

Search for narrow NNπ resonances in exclusive pp→ppππ measurements

Narrow structures in the range of a few MeV have been searched for in ppπ⁺ and ppπ⁻ invariant mass spectra (M_ppπ⁺ and M_ppπ⁻) obtained from exclusive measurements of the pp→ppπ⁺π⁻ reaction at T_p=725,750 and 775 MeV using the PROMICE/WASA detector at CELSIUS. The selected reaction is particularly well suited for the search for dibaryon resonances decoupled from NN and/or NΔ. In the mass range 2020 MeV/c²<m_dibaryon<2085 MeV/c² no narrow structures could be identified on the 3σ level of statistical significance neither in M_ppπ⁻ nor in M_ppπ⁺ giving an upper limit (95% C.L.) for dibaryon production in this reaction of σ<20 nb.     

关于低阶K群的若干问题

本文主要介绍了低阶Ｋ群Ｋ＿０，Ｋ＿１，Ｋ＿２及与它们相关的Ｂａｓｓ－Ｑｕｉｌｌｅｎ猜测、Ｂｉｒｃｈ－Ｔａｔｅ猜测研究的最新进展．Ｋ＿０与Ｋ＿１方面主要通过对Ｂａｓｓ～Ｑｕｉｌｌｅｎ猜测研究说明Ｋ＿０，Ｋ＿１的作用，同时也给出了一些多项式环上投射模自同构群的计算公式．在Ｋ＿２群方面，我们主要介绍了域上Ｋ＿２群，代数整数环上Ｋ＿２群以及著名的Ｂｉｒｃｈ－Ｔａｔｅ猜想．并且也给出了Ｋ＿２群一些计算方面的结果．