B ) in isar imaging of moving targets with high speed and acceleration , the echo signal is decomposed by emd , which is used to remove the high frequency component induced by high speed or acceleration 2 、针对高速和加速度并存的机动目标,通过对回波信号的emd分解,去除由于高速和加速度产生的高频成分,用优化后的余量进行isar成像。
Besides , during the process of empirical mode decomposition ( emd ) , the error resulting from the boundary problem is becoming more . a semi - periodical ? semi - symmetrical method is presented to reduce the error 另外,针对emd中存在的边界影响问题,本文在信号左、右边界上分别对信号进行周期处理和对称处理(镜像) ,提出对信号“半周期半对称”延拓算法。
The results show that lioh ? h2o and emd are better and cheaper materials which have no environmental pollution . it was found that the synthesis temperature were important factor . the spinel lithium manganese oxide , 结果表明: lioh ? h _ 2o和emd是制备锂离子电池正极材料掺钴锰酸锂较好的合成原料,同时也是廉价、环保的合成原料; 750 , 20h为较好的合成温度。
