Nonlinear Delay Differential Equations Oscillation Criteria For

Oscillation theary of delay differential equations is an important branch of theary of functional differential equations. In the recent years, in the study of the oscillation problems for delay differential equations second order equations and some certain higher order partial differential equations with delays attract wide attention because of their deep applied backgrounds. In this paper, we discuss oscillation for a class of second order equations with continuous distrubuted delays and two classes of neutral partial functional differential equations and obtain several new results, which improve or generalize existing known ones(see[7],[13],[22],[25],[41],[42],[43])The thesis is divided into four sections according to contents.In Chapter 1, we introduce the background and present situation of oscillation of functional differential equations.In Chapter 2 we study the equationsoccillation criteria by H-method,Riccati techniques and interval averagence.and generalize existing results in the literature.In Chapter 3, we studyby the way of taking higher order into two order and H-method. We obtain some oscillation criteria.In Chapter 4, we study by using analytic technique.