Lienard系统的同宿轨族与闭轨族

本文讨论Ｌｉｅｎａｒｄ系统解的一些定性性质，得到了存在同宿轨族、闭轨族、双曲扇形和椭圆扇形、正负半轨有界及其与等倾线相交的充要条件或充分条件．     

HARMONIC MAPS AND FUNDAMENTAL GROUPS OF NONPOSITIVELY CURVEDRIEMANNIAN MANIFOLDS

Ｔｈｅｔｈｅｏｒｙｏｆｈａｒｍｏｎｉｃｍａｐｓｉｎｔｏａｃｏｍｐａｃｔｎｏｎｐｏｓｉｔｉｖｅｌｙｃｕｒｖｅｄｔａｒｇｅｔｉｓｗｅｌｌ-ｄｅｖｅｌｏｐｅｄ.ＴｈｅｅｘｉｓｔｅｎｃｅｏｆｓｕｃｈａｈａｒｍｏｎｉｃｍａｐｐｉｎｇｉｎａｎｙｇｉｖｅｎｈｏｍｏｔｏｐｙｃｌａｓｓｉｓｅｓｔａｂｌｉｓｈｅｄｂｙＥｅｌｌｓａｎｄＳａｍｐｓｏｎ[1]ｉｎ1964,ａｎｄｌａｔｅｒ,ｉｎ1967,Ｈａｒｔｍａｎ[2]ｇａｖｅａｐｒｏｏｆｏｆｔｈｅｕｎｉｑｕｅｎｅｓｓ.Ｔｈｉｓｐａｐｅｒｉｓｄｅｖｏｔｅｄｔｏａｎａｐｐｌｉｃａｔｉｏｎｏ…     

一类抛物－椭圆耦合方程组混合初边值问题的二阶收敛差分格式Ⅰ

一类抛物－椭圆耦合方程组混合初边值问题的二阶收敛差分格式Ⅰ孙志忠（东南大学数学力学系）ＡＳＥＣＯＮＤ－ＯＲＤＥＲＤＩＦＦＥＲＥＮＣＥＳＣＨＥＭＥＦＯＲＴＨＥＭＩＸＥＤＩＮＩＴＩＡＬ－ＢＯＵＮＤＡＲＹＶＡＬＵＥＰＲＯＢＬＥＭＯＦＡＣＬＡＳＳＯＦＰＡＲＡ...     

ON THE ORDER PROPERTIES OF DIGITAL CURVES IN THE PAN-EUCLIDEAN GEOMETRY

How to increase the speed in drawing and recognizing curves has always been a major concern. From the Breshenham Algorithm and DDA Algorithm in the sixties to the double-step and quadruple-step line generation iu the eighties, curves were all dragon point by point. The algorithm in this paper fully utilizes machine commands to accelerate the generation of lines and curves. We introduce and prove for the first time characterization theorems of the segment code order of digital lines and curyes. These theorems give new methods in the recognition and the measure of smoothness of lines and curves.     

线性加指数效用函数的组合投资研究

应用无差异曲线法较好地解决了在投资决策分析中具有特殊重要地位的线性加指数效用函数的最优组合投资比例的求解问题,并给出实例予以说明.     

A Summation Formula for Estimating the Surface Areas of Ellipsoids

In this paper a summation formula for finding the surface area of general ellipsoids is derived.     

一类散度型椭圆方程的很弱解

本文研究满足一致椭圆型条件的散度型椭圆方程 ∑ni,j=1ddxjai,j(x) dudxi =0的很弱解 ,并以Hodge分解和弱逆H lder不等式为工具 ,证明了其正则性结果 :对任意的 2 - 2 n 1× 1 0 0 n2βα( 2 n 2 1 ) 2 -12 ,使得对其任意很弱解u∈W1r,loc(Ω) ,都有u∈W1p ,loc(Ω) .特别 ,u是其通常意义下的弱解 .     

铁磁材料磁化曲线的智能观测系统

利用单片机系统控制物理实验过程，智能地测绘起始磁化曲线和磁滞回线，从而使学生们看到完整的磁化过程，对铁磁物质的磁滞现象有个充分的认识。