In this paper we shall consider the following nonlinear delay differential equationwhere and are positive integers, () and () are positive periodic functions of period In the nondelay case we shall show that (*) has a unique positive periodic solution , and provide sufficient conditions for the...

The approximated method of probability density function based on the decomposition of Laguerre orthogonal polynomials is proposed for processing of decay data.With the help of this method a decay of sixteen various isotopes is investigated. It is shown, that takes place a significant deviation...

In this paper, the previous definition of the Reverse Jacket matrix (RJM) is revised and generalized. In particular, it is shown that the inverse of the RJM can be obtained easily by a constructive approach similar to that used for the RJM itself. As new results, some useful properties of RJMs,...

In this paper we shall consider the nonlinear delay differential equationwhere () denotes the density of mature cells in blood circulation and the time delay is the time between the production of immature cells in the bone marrow and their maturation for release in the circulating bloodstreams....

In this paper we shall consider the nonlinear delay differential equationwhere and are positive integers, () and λ() are positive periodic functions of period . In the nondelay case we shall show that (*) has a unique positive periodic solution , and provide sufficient conditions for the global...

In this paper we consider the ørst order neutral delay dioeerential equations with positive and negative coefficients. Some several new sufficient conditions for oscillation of all solutions are obtained. Our results extend and improve some results in the literature

The domatic number of a graph denoted (), is the maximum possible cardinality of a family of disjoint sets of vertices of each set being a dominating set of It is well known that every graph without isolated vertices has () ≥ 2. For every it is known that there are graphs with minimum degree...

Let be an Eulerian bipartite digraph with vertex partition sizes . We prove the following Turán-type result: If then contains a directed cycle of length at most 4. The result is sharp. We also show that if and no directed cycle of length at most 4 exists, then must be biregular. We apply this...

We prove that the determinacy of all Lipschitz games, the determinacy of all Wadge games, and the semi-linear ordering principle for Lipschitz maps are all equivalent. Several standard consequences of on the Wadge hierarchy are generalized to the Borel context