x(t)的频谱是X(f),y(t)的频谱是Y(f),若在频域内X(f)与Y(f)作相乘运算,则对应在时域内x(t)与y(t)应作()
参考答案:卷积
The most important thing to remember when launching an inflatable liferaft by hand is to().
A.open the CO2 inflation valve
B.open the raft container
C.ensure that the operating cord is secured to the vessel
D.inflate the raft on the vessel,then lower it over the side
试述提高客户满意度的方法和技巧。