Due to its wide bandwidth , krf laser beam is ready to be homogenized by a method called induced spatial incoherence ( isi ) to generate uniform illumination on target , which is critical to eos measurements . a long pulse is also preferred to get a " cold " acceleration of flyer in impact experiments 在激光能量30焦耳、脉冲长度50ns 、焦斑直径300um 、聚焦功率密度8 . 5 10 ~ ( 11 ) w cm ~ 2的条件下，考察了激光对飞片的加速效果、飞片的平面性与聚焦激光的平面性之间的关系。
Our experimental results show that , comparing with exhaustive search , when the class number is 25 , we obtain 17 times speed - up ratio , with only image degeneration of 1 . 574951db , at the same compression ratio . compared with other classification schemes , our method can provide more speed - up and better quality of decoded image . 2 我们做了大量的数值实验，结果表明，在压缩比相同的前提下，与全局搜索法相比，将图像块分为25类时，可取得约17倍的加速比，而解码质量只相差1 . 574951db ；另外，与其他分类方法的比较实验表明，本方法有更好的加速效果和解码质量。
It indicates that the moving grid generation method used in this paper is simple , fast and easy to deal with the boundary conditions of the upstream and downstream . the use of the fully implicit dual - time stepping method in this paper can greatly decrease the calculating time of the three - dimensional unsteady flow in vibrating cascades to satisfy the engineering practice requirement . the efficiency of this acceleration method is very high 实践表明，本文的运动网格生成方法简单、快捷、便于进行上、下游边界条件处理，能够给出较准确的振动叶栅非定常流场解；本文计算采用的全隐式双时间方法将三维非定常粘流的计算时间降至工程可以接受的程度，加速效果十分突出。
