φ－满射环上GL_n（R）中元素的三角分解

本文结果是：设Ａ是φ－满射环Ｒ上的非拟纯量可逆ｎ×ｎ矩阵，βｊ，γｊ（尔≤ｊ≤ｎ）是Ｒ中任意元素，它们满足Πｎｊ＝１βｊγｊ＝ｄｅｔＡ，则存在ｎ阶阵Ｂ和Ｃ满足ＰＡＰ－１＝ＢＣ，其中Ｂ是下三角阵，Ｃ是上三角阵，Ｐ∈ＧＬｎ（Ｒ）．进一步，可以取Ｂ使βｊ（１≤ｊ≤ｎ）位于Ｂ的主对角线上，同时可以取Ｃ使γｊ（１≤ｊ≤ｎ）位于Ｃ的主对角线上．     

厄米特矩阵的迹的几点性质

应用矩阵Ａ＝（ａｉｊ）∈Ｃｎ×ｎ的弗罗伯尼范数ＡＦ和谱范数ＡＳ，研究厄米特矩阵的迹的性质，得到几个结论：Ｔｒ（ＡＢ）＝∑ｎｉ＝１λｉ∑ｎｊ＝１ｔｉｊμｊ（λｉ，μｊ分别为Ａ，Ｂ的特征值，０≤ｔｉｊ≤１，且∑ｎｉ＝１ｔｉｊ＝１，ｊ＝１，２，…，ｎ）；Ｔｒ（ＡＢ）≤Ｔｒ（Ａ）ＢＳ；Ｔｒ（ＡＢ）Ｈ（ＡＢ）］≤Ｔｒ（ＡＨＡ）［ｍａｘ１≤ｉ≤ｎλｉ］２（λｉ是Ｂ的特征值）等．     

矩阵方程AXB=C的通解

本文给出了矩阵方程 Ａ_（ｍ×ｎ）Ｘ_（ｎ×５）Ｂ_（ｓ×）＝Ｃ_（ｍ×ｔ）有解且有无穷解的通解表达式 Ｘ＝Ｃ~（＊＊）＋［ｋ_（１１）ξ_１~Ｔ＋…＋ｋ_（１（ｎ－ｒ））ξ_（ｎ－ｒ）~Ｔ＋……ｋ_（ｓ１）ξ_１~Ｔ＋…＋ｋ_（ｓ（ｎ－ｒ））ξ_（ｎ－ｒ）~Ｔ］ ＋［Ｐ_（１１）η_１＋…＋Ｐ_（１（ｓ－１））η_（ｓ－１）……Ｐ_（ｎ１）η_１＋…Ｐ_（ｎ（ｓ－１））η_（ｓ－１）］~Ｔ（其中ｋ_（ｉｊ）;Ｐ_（ｉｊ）为任意常数;ξ_１…,ξ_（ｎ－ｒ）;η_１…,η_（ｓ－１）分别为Ａ_（ｍ×ｎ）Ｘ_（ｎ×１）＝０;Ｘ_（１×ｓ）Ｂ_（ｓ×ｔ）＝０的一个基础解系,Ｃ~（＊＊）为ＡＸＢ＝Ｃ的一个特解）及利用矩阵初等变换求其通解的方法．     

φ－满射环上GLｎ（R）中元素的三角分解

本文结果是：设Ａ是φ－满射环Ｒ上的非拟纯量可逆ｎ×ｎ矩阵，β_j，γ_j（1≤ｊ≤ｎ）是Ｒ中任意元素，它们满足Π_j=1^{nβ_jγ_j＝ｄｅｔＡ，则存在ｎ阶阵Ｂ和Ｃ满足ＰＡＰ－１＝ＢＣ，其中Ｂ是下三角阵，Ｃ是上三角阵，Ｐ∈ＧＬ_ｎ（Ｒ）．进一步，可以取Ｂ使β_j（１≤ｊ≤ｎ）位于Ｂ的主对角线上，同时可以取Ｃ使γ_j（１≤ｊ≤ｎ）位于Ｃ的主对角线上．}     

二项式定理的推广

二项式定理的推广陈皓（湖北省邮电学校４３００７２）设ｍ≥１，对于多项式（１＋ｘ＋…＋ｘｍ）ｎ＝ｎｍｊ＝０ａｊｘｊ，约定展开式中含ｘｊ项的系数ａｊ＝ｆｍ（ｎ，ｊ），易知ｆ１（ｎ，ｊ）＝Ｃｊｎ．定理１若０≤ｔｉ≤ｍ（ｉ＝１，２，…，ｎ），则ｆｍ（ｎ，ｊ...     

对概率论中一个大数律证明题的讨论

在我国出版或翻译出版的一些概率论习题集中有这样一道题：设｛ξｎ｝为具有相同的数学期望、方差（有界）的随机变量序列,且当ｉ≠ｊ时Ｅ（ξｉξｊ）≤０,证明｛ξｎ｝服从（弱）大数律．参见［１］、［２］．按照有些书提示的证明方法,可设对任意ｎ有Ｅξｎ＝μ,Ｄ...     

一台机器在加工时间相同准备时间可控时的Lmax问题

一组ｎ个工件需在一台机器上加工，工件ｊ所需的加工时间，应交工时间、准备时间分别为ｐｊ、ｄｊ、ｒｊ＾０，准备时间可压缩量为ｘｊ，０≤ａｊ≤ｒｊ＾０，压缩权因子为ωｊ由最大延误Ｊｍａｘ和压缩费用∑ωｊｘｊ可构成文中（Ｐ１）－（Ｐ３）三个排序问题，在ｄｊ＝０的条件下，引文「１」的作者证明了（Ｐ１）、（Ｐ３）为强ＮＰ－Ｃ的。本文在ｄｊ任意，ｐｊ＝ωｊ＝１的条件下，对（ｐ１）－（Ｐ３）给出了一个伪多项式时间     

θ(t)-Caldern-Zygmund算子在群上的Hardy空间H~p(G)中的有界性

设Ｇ为局部域Ｋ上的２ｎ＋１维Ｈｅｉｓｅｎｂｅｒｇ群,文献［１］给出了一类Ｈａｒｄｙ空间 Ｈ~ｐ（Ｇ）,（０＜Ｐ≤１）,本文讨论了θ（ｔ）－Ｃａｌｄｅｒｏｎ－Ｚｙｇｍｕｎｄ算子在Ｈ~ｐ（Ｇ）（０＜Ｐ≤１）中的有界性。     

线性常微分方程组解的特征数的估计

复数域上线性系统ｘ＝Ａ（ｔ）ｘ，当Ａ（ｔ）＝（ａｉｊ（ｔ））ｎ×ｎ具有（ｎ，Ｎ，ｒ） 差异性质且ｒｎ时，解的特征数ｊ有估计λｊ－ｌｉｍｔ→∞１ｔ∫ｔｔ０Ｒｅａｊ（τ）ｄτｎ－１ｒ＋１－ｎｌｉｍｔ→∞１ｔ∫ｔｔ０Ａ（τ）ｄτ，ｊ＝１，２，…，ｎ，其中Ａ（ｔ）＝ｍａｘ｛｜ａｉｊ（ｔ）｜：ｉ，ｊ＝１，２，…，ｎ，ｉ≠ｊ．｝     

贪婪t－相交有限序列族

设Ｆ为有限序列族，对ａ＝（ａ１，ａ２，…，ａｎ）∈Ｆ，ａｉ为整数且０≤ａｉ≤ｓｉ（整数），记ｓ（ａ）＝｛ｊ｜１≤ｊ≤ｎ，ａｊ＞０｝，ｓ（Ｆ）＝｛ｓ（ａ）｜ａ∈Ｆ｝，及Ａ｛１，２，…，ｎ｝时Ｗ（Ａ）＝Пｉ∈Ａｓｉ．称Ｆ为贪婪ｔ－相交，如对任何ａ，ｂ∈Ｆ，至少有ｔ个ａｉ，ｂｉ＞０，且Ｗ（Ａ）≥Ｗ（（｛１，２，…，ｎ｝－Ａ）＋Ｂ）对任何Ａ∈Ｓ（Ｆ）及ＢＡ（｜Ｂ｜＝ｔ－１）成立．本文得到当ｓ１＞ｓ２＞…＞ｓｎ时的最大贪婪ｔ－相交有限序列族．     

RECENT PROGRESS ON SPHERICAL HARMONIC APPROXIMATION MADE BY BNU RESEARCH GROUP ——In memory of Professor Sun Yongsheng

As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years （2001-2005）. The main topics are： convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.     

Instructions for Authors

<正>Submission Authors must use LaTeX for typewriting,and visit our website www.actamath.com to submit your paper.Our address is Editorial Office of Acta Mathematica Sinica,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,P.R.China.     

THE 8~(th) INTERNATIONAL CONGRESS ON INDUSTRIAL AND APPLIED MATHEMATICS

正August 10-14,2015Beijin,China The International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists     

Boundedness for commutators of multipliers on Hardy type spaces

In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p（R^n） into the Lebesgue space L^p with p 〈 1.     

A unified approach to certain problems of best local approximation

In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.     

Towards Excellence in Science Chinese Academy of Sciences

<正>May 26,2014,Beijing Science is a human enterprise in the pursuit of knowledge.The scientific revolution that occurred in the 17th Century initiated the advances of modern science.The scientific knowledge system created by     

THE 8~(th) INTERNATIONAL CONGRESS ON INDUSTRIAL AND APPLIED MATHEMATICS

<正>August 10-14,2015Beijing,ChinaThe International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists     

Bounds for the zeros of polynomials

Let P(z)=∑↓j=0↑n ajx^j be a polynomial of degree n. In this paper we prove a more general result which interalia improves upon the bounds of a class of polynomials. We also prove a result which includes some extensions and generalizations of Enestrǒm-Kakeya theorem.