function y = variasi_beban(x)
B = 0.654;
T = 0.5;
t = x(1);
w = x(2);
if t <= T
    y = 0;
elseif t <= 2*T
    y = 0.2*B*w;
elseif t <= 3*T
    y = 0.4*B*w;
elseif t <= 4*T
    y = 0.6*B*w;
elseif t <= 5*T
    y = 0.8*B*w;
else
    y = B*w;
end