we study umbilic (space-like) submanifolds of pseudo-riemannian space forms, then define totally semi-umbilic space-like submanifold of pseudo euclidean space and relate this notion to umbilicity. finally we give characterization of total semi-umbilicity for space-like submanifolds contained in pseudo sphere or pseudo hyperbolic space or the light cone.a pseudo-riemannian submanifold m in (a ps...

darabgird is one of the ancient cities in fars province. according to iranian mythology, darab shah (dariush, the great) found the city in the achaemenid period. but, due to the fact that 1.21% of total ceramics gathered from the city belongs to the parthian era, we can accept that the city remained in use since parthian period to the islamic era. data analysis shows that the city had a strong...

abstract: in the present paper, we give a necessary and sufficient condition for contact cr-warped product to be contact cr-product in kenmotsu space forms.

visibility is an important factor of environmental quality that has various influences on the quality of neighborhood. this paper aimed to find the relationship between urban form and visual quality. a public space with a spatial configuration in one of bushehr city's neighborhoods was selected as the case study. bushehr city is surrounded by urban development and the sea. compact urban sp...

nowadays “design” is considered as an independent discipline which is neither a science, nor an art, but an interdiscipline with strong relations with both art and science. therefore, this new understanding demands reidentifying all design sub-disciplines. “space” as one of this sub-disciplines, has a pivotal role in shaping form in both design and architecture. while concrete understanding of ...

let $(m^{2n},g)$ be a real hypersurface with recurrent shapeoperator and tangent to the structure vector field $xi$ of the sasakian space form$widetilde{m}(c)$. we show that if the shape operator $a$ of $m$ isrecurrent then it is parallel. moreover, we show that $m$is locally a product of two constant $phi-$sectional curvaturespaces.

Involving the Ricci curvature and the squared mean curvature, we obtain basic inequalities for different kind of submaniforlds of a Sasakian space form tangent to the structure vector field of the ambient manifold. Contrary to already known results, we find a different necessary and sufficient condition for the equality for Ricci curvature of C-totally real submanifolds of a Sasakian space form...

Let $(M^{2n},g)$ be a real hypersurface with recurrent shapeoperator and tangent to the structure vector field $xi$ of the Sasakian space form$widetilde{M}(c)$. We show that if the shape operator $A$ of $M$ isrecurrent then it is parallel. Moreover, we show that $M$is locally a product of two constant $phi-$sectional curvaturespaces.