c＝3，N＝2超共形场论的Z2 0rbifold—Prime模型

讨论了二维环面上中心荷c＝3，N＝2的超共形场论。特别给出该理论的配分函数，进一步，为了产生新的模型，回顾了一般的orbifold方法，然后构造了模不变的Z2 0rbifold—Prime模型。     

关于共形平坦流形中子流形的不等式

本文目的在于建立共形平坦黎曼流形中子流形的数量曲率截面曲率间关系的几个不等式,在流形是常曲率的情况下,这些不等式改进了B.Y.Chen和M.Okumura的结果。§1.基本公式和引理设M~(n+p)是一个n+p维的共形平坦黎曼流形,V~n是M~(n+p)的n维子流形。在M~(n+p)中选取局     

NUMERICAL ANALYSIS OF QUASICONFORMAL MAPPINGS BY CIRCLE PACKINGS

Thurston proposed that conformal mappings can be approximated by circle packing isomorphisms and the approach can be implemented efficiently. Based on the circle packing methods the rate of convergence of approximating solutions for quasiconformai mappings in the plane is discussed.     

两类拟共形映射的掩盖定理

In this paper we define two classes of quasiconformal mappings,and study their covering properties by methods of module.We obtain some new results.In the meantime,we give new methods to prove Koebe 1/2 covering theorem on convex conformal mappings.     

借形解题的几点注意

借形解题是以“形”研究“数”,它使我们可以借助直观,从整体上、本质上透视问题,十分有利于问题的解决.但是,如果忽视了图形的正确性、存在性、完整性和简洁性往往会使解题陷入困境或导致错误.1注意图形的正确性例1设t>0,求坐标平面上的两点A t 1t,t-1t,B(-1,0)之间的距离的最     

A New Holographic Entropy Bound from Conformal Field Theory at the Killing Horizon

A new holographic entropy bound is obtained by using conformal field theory at the Killing horizon.The entropy bound is tighter than the well-known bounds,such as the Bekenstein,Bekenstein-Mayo and‘t Hooft bounds.The result shows that the entropy of a system decreases when quantum effects are included.Therefore,the quantum effect will increase the degree of order of the system.     

近终形连铸技术的发展状况

近终形连铸技术是当今冶金科技领域的一门前沿学科。本文介绍目前近终形连铸技术的发展及趋势。在世界各国的研究中，美国比较注重单辊法，日本侧重于双辊法，西欧则侧重于改进结晶器的结构和功能，开发新型铸机