But, as with any parent-child relationship, all loving intentions can be tempered by issues of control, role-reversal, guilt and a little deception - enough loaded stuff to fill a psychology syllabus.

In order to carry out the constant line speed and the constant tension for the rolling of plastic films during reversal, loop control of the rotating speeds and the tension is adopted.

This breaks through the traditional knowledge about airflow reversal and helps to find more effective control measurements for such kind of mine fires.