中文说明：
某炼厂常压塔实测数据和人工化验结果（汽油干点）。假设输入变量为常顶温度、顶回流温度、进料温度、进料压力、常顶压力共5个变量；输出量为汽油干点。试用BPNN建立此常压塔汽油干点软测量模型。
English Description：
The measured data and manual test results of atmospheric tower in a refinery (gasoline dry point). Suppose that the input variables are constant top temperature, top reflux temperature, feed temperature, feed pressure and normal roof pressure, and the output is gasoline dry point. BPNN is used to establish the soft sensing model of gasoline dry point of atmospheric tower.