Vertical and temporal distributions of N and P in soil solution in aquatic-terrestrial ecotone (ATE) of Taihu Lake were investigated, and the relations among N,
A homomorphism ψ of logic programs from P to P is a function mapping Atoms(P) to Atoms(P) and paper, the complexity of the decision problems on homomorphism an
A typed category theory is proposed for the abstract description of knowledge and knowledge processing. It differs from the traditional category theory in two d