角块 meaning in Chinese

angle block
horn block

Angle masters with various angles , prisms , corner cubes and lage aperture and high precision cemented plate
不同角度的标准角块、棱镜、角反射器（角锥棱镜）及大口径、高精度的光胶板。
In the first part , we study three kinds of pre - conditioners - - block - triangular preconditioner , constraint preconditioner and block - diagonal preconditioner respective1y and fast iterative so1vers for indefinite 2 by 2 b1ock linear systems with zero ( 2 , 2 ) block . the spectrum and form of eigenvalues of each preconditioned nlatrix are presented . all of the three kinds of preconditioned linear systems are so1ved by gmres ( 20 ) and theii efficiencies are cornpared
在第一部分中，我们研究了三种不同的预条件矩阵一块三角预条件矩阵、约束预条件矩阵和块对角预条件矩阵作用到2 2块线性系统(其中右下角块为零)以后的快速迭代解法，给出了预条件作用后系统的特征值的谱和形式，比较了三种不同预条件作用后采用cmres ( 20 )方法求解的有效性。