x_{6} = \operatorname{piecewise}(1, \operatorname{and}\left(t \ge 0, t < 5\right), 0)\\
x_{8} = \operatorname{piecewise}(0, \operatorname{and}\left(t \ge 0, t < 5\right), \operatorname{piecewise}(1, \operatorname{and}\left(t \ge 5, t < 10\right), 0))