ON THE CONSTRUCTION OF ALGEBRAIC-GEOMETRIC CODES

1,Illtroduction'SincetheearlypapersbyG0ppa[1-31,algebralc-ge0metriccodeshavebeeninthespotlight0fcodingthe0reticresearchf0rab0uttwodecades.NumerousexcitingresultshavebeenachievedusingGoppa'sconstructi0noflinearcodesfromalgebralccurvesoverfinitefields,bothbyalgebraicge0metorsandcodingtheorists.Becauseofthedifficultyofthesubject,severalexplanatorypaPersandtextbookshaveappeared,seeforinstance[4-8].Inthispaperwepresentaquitedtherentpointofviewconcerningalgebraic-geometriccodes.Itiswellknownthataq…     

关于亚纯函数的奇异方向

证明了对应于杨明泽，王平在《一类亚纯函数的正规定则与奇异方向》一文中所得一亚纯函数正规定则的奇异方向的存在性，由此推广了陈怀惠《一个基本不等式及相应的奇异方向》中的１个结果。     

解析几何中的两个问题

本文讨论了解析几何中的两个疑难问题，它有益于解析几何的教学和研究。     

布尔函数零化子的构造方法分析

寻找布尔函数的零化子是进行代数攻击的关键.本文对三种构造布尔函数的零化子的方法来进行了分析和讨论,并用实例对三种构造方法计算量给出了估算结果,得出了它们之间的差异.     

第四类扩充空间P_(Ⅳ)(1,N 2)上的共轭点

讨论第四类扩充空间ＰⅣ（１，Ｎ＋２）（Ｎ≥２）上的共轭点及其重数以及有关应用．首先求出连结ｐ＝π（１，ｉ，０，…，０）与ｑ＝π（０，０，１，ｉ，０，…，０）的测地线，然后求出相应矩阵Ａ的特征值，再讨论共轭点．     

ri(A+B)riA+B成立的条件

根据使得int(A B)intA B成立的已有结论,在集合相对代数内部和相对拓扑内部概念的基础上,分别给出了线性空间中(A B)ri Ari B和线性拓扑空间中ri(A B)riA B成立的条件,从而将cor(A B)corA B和int(A B)intA B关于内部的结论推广到了相对内部的情形。     

求解一类块线性代数方程组的LU分解算法

本文针对一类块线性代数方程组的大型、稀疏的特点,采用压缩存储技术,设计出了LU分解算法,计算表明:该算法效果良好。     

Non-fragile decentralized H∞ controller design for uncertain linear systems

Considering the design problem of non-fragile decentralized H∞ controller with gain variations, the dynamic feedback controller by measurement feedback for uncertain linear systems is constructed and studied. The parameter uncertainties are considered to be unknown but norm bounded. The design procedures are investigated in terms of positive definite solutions to modify algebraic Riccati inequalities. Using information exchange among local controllers, the designed non-fragile decentralized H∞ controllers guarantee that the uncertain closed-loop linear systems are stable and with H∞ -norm bound on disturbance attenuation. A sufficient condition that there are such non-fragile H∞ controllers is obtained by algebraic Riccati inequalities. The approaches to solve modified algebraic Riccati inequalities are carried out preliminarily. Finally, a numerical example to show the validity of the proposed approach is given.     

gj图的性质及其应用

讨论了COD（除之符合）展开式的gj图的读图规则及除项中变量数图，对毋图的性质作了进一步的研究，提出了若干新的性质，给出了相应的证明．并对其应用及实例进行了讨论．实例表明图形方法具有简单、直观等优点．讨论揭示了gj图的内在规律，有助于开拓岛图的应用领域．     

数值积分中代数精度的讨论

对于给定节点个数情况下,各种节点位置对代数精度的影响及对代数精度限制范围进行全面讨论.这对在数值积分中的主要公式插值型和Gauss型求积公式的适用范围、精确度有一个全面清楚的了解.