function y=F15_FITNESS(x)
global dimension
global popsize
a=[0.1957 0.1947 0.1735 0.16 0.0844 0.0627 0.0456 0.0342 0.0323 0.0235 0.0246];
b1=[0.25 0.5 1 2 4 6 8 10 12 14 16];
b=1./b1;
t=0;
for i=1:11
    A1=b(1,i)*x(2,:);
    A2=A1+b(1,i)^2;
    A3=x(1,:);
    A=A2.*A3;
    B1=b(1,i)*x(3,:);
    B=B1+b(1,i)^2+x(4,:);
    C=A./B;
    D=a(1,i)-C;
    E=D.^2;
    t=t+E;
end
y=t;