一、一个月;保甲法户籍外勤民警;主管人;20年;一年;五年;服务性。 二、AA;C;D;D;B 三、1、ABDE;2、ABD;3、AD;4、ABCE;5、BCE

1. For our English homework we have to write a paper. A three-thousand-word B. three-thousands-word C. three-thousand-words d. three -thousands-word 2. Jack English in the university for 30 years by the end of next mon A. will teach B. had taught C will have taught D. has taught

概述 一、信源的原始信号绝大多数是模拟信号,因此,信源编码的第一个任务是模拟和数字的变换,即:A/D,D/A 二、样率取决于原始信号的带宽:f=2×,w为信号带宽 三、抽样点的比特数取决于经编译码后的信号质量要求: SNR=6×(dB),L为量化位数