Almost ?-cosimplectic (?,?,?)-spaces

This thesis consists of seven chapters. The first chapter is devoted to the introduction section and provide a generel knowledge of literature. In the second chapter, we have given about the basic concepts needed. In the third chapter, curvature properties of the almost ?-cosymplectic manifolds are given and some relationships with some paralel tensor fields are examined. In the fourth chapter, by introducing the almost ?-cosymplectic f-structures, general results are given. In the fifth chapter, some results about the invariant submanifolds of almost ?-Kenmotsu manifolds are obtained. In the sixth chapter, the conformal flat almost ?-cosymplectic manifolds with Kaehlerian integral submanifolds are investigated. In the seventh chapter, all the results connected to the (?,?,?)-spaces obtained so far will be examined in detail by using the D-homothetic transformations and some general results are given on almost ?-cosymplectic manifolds.