什么叫积分增益?
参考答案:
对于永态转差系数为零的调速系统,接力器速度(dy/dt)与给定的转速相对偏差x之比的负值称为积分增益Ki。即:Ki=-(dy/dt)/x。
The reporter _____ that the girl who was so _____ was trying not to answer the question. [ ]
A. recognized; frightening
B. realized; frightened
C. recognized; frightened
D. realized; frightening
下列哪项不是胸廓成形术的适应证()
A.上叶空洞,病人一般情况差
B.一侧广泛肺TB灶,药物治疗无效,一般情况差不能耐受全肺切除术
C.肺TB合并脓胸或支气管胸膜瘘不能耐受肺切除术者
D.张力空洞,厚壁空洞
E.上叶空洞但中下叶亦有TB