By using the fixed point theorem in double cones,we study the existence of at least two positive solutions for the discrete three-point boundary value problem(BVP)Δ~2y(k-1)+a(k)f(k,y(k))=0,k∈N={1,2,…,T},Δy(0)=0,y(T+1)=βy(l),where f is allowed to change sign,l∈N_1=｛2,3,…,T-1｝,T∈｛3,4,…｝.

Characteristics of a gas-solid fast separator with two coaxial cones in a concurrent downer reactor;

On the basis of the structural characteristics of the common conical basket centrifuge, a new centrifuge with double cone angles conical basket is put forward in the paper.

Finite element analysis of a horizontal screw decanter centrifuge drum with double tapered beach;