Totally umbilical

In this paper, we generalize the geometry of the invariant submanifolds of Riemannian product manifold to the geometry of the invariant submanifolds of Riemannian warped product manifold.

17p danhdanh27 07-01-2019 22 1   Download

In this paper, the geometry of F-invariant submanifolds of a Kaehlerian product manifold is studied. The fundamental properties of these submanifolds are investigated such as pseudo umbilical, curvature invariant, totally geodesic, mixed geodesic submanifold and locally decomposable Riemannian product manifold.

15p danhdanh27 07-01-2019 15 1   Download

The aim in the present paper is to study some basic geometric properties of semi-slant submanifolds of a nearly Kaehler manifold.

13p danhdanh27 07-01-2019 18 1   Download

We mainly deal with the problem of admissibility for screen distributions on a lightlike hypersurface of both a semi-Riemannian manifold and an indefinite S -manifold. In the latter case, we first show that a characteristic screen distribution is never admissible, and then we provide a characterization for admissible screen distributions on proper totally umbilical lightlike hypersurfaces.

13p tuongvidanh 06-01-2019 23 2   Download

In this paper, we research the existence or non-existence of warped product semi-slant submanifolds in Kenmotsu manifolds. Consequently, we see that there are no proper warped product semi-slant submanifolds in Kenmotsu manifolds such that totally geodesic and totally umbilical submanifolds of warped product are proper semi-slant and invariant (or anti-invariant), respectively.

8p tuongvidanh 06-01-2019 17 3   Download

This paper deals with the relative nullity distributions of lightlike hypersurfaces of indefinite Kenmotsu space forms, tangent to the structure vector field. Theorems on parallel vector fields are obtained. We give characterization theorems for the relative nullity distributions as well as for Einstein, totally contact umbilical and flat lightlike hypersurfaces.

21p tuongvidanh 06-01-2019 25 2   Download

(bq) part 2 book "master techniques in surgery hernia" presentation of content: laparoscopic transabdominal preperitoneal inguinal hernia repair, totally extraperitoneal inguinal hernia repair, onlay mesh repair, sports hernia, umbilical hernia repair, massive ventral hernia with loss of domain, components separation,...and other contents.

176p thangnamvoiva23 06-10-2016 44 4   Download