The structure of doubly periodic arrays over finite field F as an F[x,y]-module is studied.The necessary and sufficient conditions for the modules of doubly per
The monotoneity properties of certain functions defined in terms of the η-distortion function ηK(t) in quasiconformal theory are studied and asymptotically sh
The global attractivity of the zero solution of the delay functional differential equation x(t)+ [1+x(t)]F(t, x(·)) =0 is studied by using a new technique.
A smash coproduct in braided monoidal category C is constructed and some conditions making the smash coproduct a Hopf algebra or braided Hopf algebra are given.
The following question raised by P. C. Hammer in 1960 is answered: Let M be the set of all positive integers, ft the closure function under multiplication defin
A geometrical method using the exponential dichotomy and the invariant manifold thoery is given to set up the criteria for the existence of transversal and tang
A generalized dimension is further developed.Here subtraction and addition of two generalized dimensions are defined,so that the operations: ∞+n=∞,∞+∞=∞,wh
In the light of a question of J. L. Krivine about the consistency of an extensional λ-theory,an extensional combinatory logic ECL+U(G)+RU_∞+ is established, w
A duality theorem for Hopf crossed coproduct is proved. This theorem plays a role similar to that appearing in the work of Koppinen (which generalized the corre
It is proved that there exists a formula of first-order logic with only one non-logical symbol, a binary function symbol Ap signifying application, which unifor