The model proposed for this situati

The model proposed for this situation is analog to the one
exposed for the loitering alarms: if there is some person loitering
near the cash desk as explained in Eq. (14) and there is not shop
personnel detected in the cash desk zone, an alarm is given off,
as was seen in the example C of Fig. 1. However, in this case the
kl estimated is around only 5 s, because this is a situation considered more risky and the control center must be quickly warned
about it. In order to understand this kind of alarm, the three typical
cash desk situations are shown in Fig. 10.