4.5.2. Constraint Function

To prevent the situation where the task cannot be finished before the timer expiration, the constraint functions for the timer expiration of IoT devices *i* and *j* can be represented by

$$c\_{\dot{l}}\left(S,A\right) = \begin{cases} 1, \text{ if } D\_{\dot{l}} = 1, \\ 0, \text{ otherwise,} \end{cases} \tag{44}$$

and

$$c\_{\hat{j}}(S, A) = \begin{cases} 1, \text{ if } D\_{\hat{j}} = 1, \\\ 0, \text{ otherwise,} \end{cases} \tag{45}$$

respectively.
