function F = KBg31F(x)
%

F(1) = -0.72835 + (1-x(1)) + x(2) - x(6)*x(2);
F(2) = -0.81011 + (1-x(2)) + (1-x(1)) + x(5) - x(7)*x(5) - x(8)*(1-x(1)) - x(8)*x(5) + x(8)*x(7)*x(5);
F(3) = -0.86729 + (1-x(5)) + x(3) + x(4) - x(9)*x(4) - x(10)*x(3) - x(10)*x(4) + x(10)*x(9)*x(4);
F(4) = -0.53447 + (x(3));
