[ Eq(Derivative(x1, t), Piecewise((1/2190, Eq(k22, 0)), (1/2190, True))*Piecewise((1000, Eq(k22, 0)), (1000, True)) - Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7)*Piecewise((19, Eq(k22, 0)), (19, True))/(Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7) + Piecewise((19, Eq(k22, 0)), (19, True))*(x1 + x3 + x2 + x4))*Piecewise((21/100, Eq(k22, 0)), (21/100, True))*x7/(x5 + x6 + x7)*x1 - Piecewise((1/2190, Eq(k22, 0)), (1/2190, True))*x1),
  Eq(Derivative(x2, t), Piecewise((2/5, Eq(k22, 0)), (2/5, True))*Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7)*Piecewise((19, Eq(k22, 0)), (19, True))/(Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7) + Piecewise((19, Eq(k22, 0)), (19, True))*(x1 + x3 + x2 + x4))*Piecewise((21/100, Eq(k22, 0)), (21/100, True))*x7/(x5 + x6 + x7)*x1 - (Piecewise((1/2190, Eq(k22, 0)), (1/2190, True)) + Piecewise((1/4, Eq(k22, 0)), (1/4, True)))*x2),
  Eq(Derivative(x3, t), (1 - Piecewise((2/5, Eq(k22, 0)), (2/5, True)))*Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7)*Piecewise((19, Eq(k22, 0)), (19, True))/(Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7) + Piecewise((19, Eq(k22, 0)), (19, True))*(x1 + x3 + x2 + x4))*Piecewise((21/100, Eq(k22, 0)), (21/100, True))*x7/(x5 + x6 + x7)*x1 - (Piecewise((1/2190, Eq(k22, 0)), (1/2190, True)) + Piecewise((1/4, Eq(k22, 0)), (1/4, True)) + Piecewise((1/10, Eq(k22, 0)), (1/10, True)))*x3),
  Eq(Derivative(x4, t), Piecewise((1/4, Eq(k22, 0)), (1/4, True))*x3 + Piecewise((1/4, Eq(k22, 0)), (1/4, True))*x2 - Piecewise((1/2190, Eq(k22, 0)), (1/2190, True))*x4),
  Eq(Derivative(x5, t), (x5 + x6 + x7 - Piecewise((1/10, Eq(k22, 0)), (1/10, True))*x7)/(x5 + x6 + x7)*Piecewise((1/20, Eq(k22, 0)), (1/14, True))*Piecewise((20000, Eq(k22, 0)), (4000, True)) - Piecewise((33/100, Eq(k22, 0)), (1/4, True))*Piecewise((19, Eq(k22, 0)), (19, True))*(x1 + x3 + x2 + x4)/(Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7) + Piecewise((19, Eq(k22, 0)), (19, True))*(x1 + x3 + x2 + x4))*(Piecewise((7/10, Eq(k22, 0)), (7/10, True))*x3/(x1 + x3 + x2 + x4) + Piecewise((3/10, Eq(k22, 0)), (3/10, True))*x2/(x1 + x3 + x2 + x4))*x5 - Piecewise((1/20, Eq(k22, 0)), (1/14, True))*x5),
  Eq(Derivative(x6, t), Piecewise((33/100, Eq(k22, 0)), (1/4, True))*Piecewise((19, Eq(k22, 0)), (19, True))*(x1 + x3 + x2 + x4)/(Piecewise((33/100, Eq(k22, 0)), (1/4, True))*(x5 + x6 + x7) + Piecewise((19, Eq(k22, 0)), (19, True))*(x1 + x3 + x2 + x4))*(Piecewise((7/10, Eq(k22, 0)), (7/10, True))*x3/(x1 + x3 + x2 + x4) + Piecewise((3/10, Eq(k22, 0)), (3/10, True))*x2/(x1 + x3 + x2 + x4))*x5 - (Piecewise((1/20, Eq(k22, 0)), (1/14, True)) + Piecewise((1/14, Eq(k22, 0)), (1/14, True)))*x6),
  Eq(Derivative(x7, t), Piecewise((1/10, Eq(k22, 0)), (1/10, True))*x7/(x5 + x6 + x7)*Piecewise((1/20, Eq(k22, 0)), (1/14, True))*Piecewise((20000, Eq(k22, 0)), (4000, True)) + Piecewise((1/14, Eq(k22, 0)), (1/14, True))*x6 - Piecewise((1/20, Eq(k22, 0)), (1/14, True))*x7) ]