问题
单项选择题
在改变给定值的反馈控制系统中,评价动态品质的指标包括()。
①超调量σp;
②衰减率φ;
③放大倍数k;
④过渡过程时间tS;
⑤震荡次数N;
⑥静态偏差ε。
A.①③④⑥
B.②④⑤⑥
C.①④⑤⑥
D.②③④⑤
答案
参考答案:C
在改变给定值的反馈控制系统中,评价动态品质的指标包括()。
①超调量σp;
②衰减率φ;
③放大倍数k;
④过渡过程时间tS;
⑤震荡次数N;
⑥静态偏差ε。
A.①③④⑥
B.②④⑤⑥
C.①④⑤⑥
D.②③④⑤
参考答案:C
阅读短文,根据短文内容,从方框中选择恰当的词填空。 | |
geography, physics, chemistry and math: Others go to school to leam a skill so that they can make money. But no one can leam everything from school. A teacher, no matter how much he knows, cannot teach his 2______ everything they want to know. His job is to help his students know how to learn. He teaches them how to read and how to 3______. So, much more is to be learnt 4______ school by the students themselves. It's always more 5______ to leam how to study by oneself than to memonze some facts or rules. Great scientists, like Newton, Galileo and Edison, didn't get 6______ from school, but they were all successful. They invented so many things. The reason for their success is that they knew how to study. They read books that were not 7______ at school. They worked hard all their lives, wasting not a single moment. Above all, they knew how to use their brains. |