function dy=liutrack(t,X)
global p;
dy=zeros(3,1);
x=X(1);y=X(2);z=X(3);
dy(1)=10*(y-x);
dy(2)=40*x-x*z-(49+0.1*p)*x+9*y+x*z+0.1*(p-1)*sin(t)+0.1*cos(t);%-16*y;
dy(3)=-2.5*z+4*x*x;