May 2014

Properties of Bertrand curves in dual space

Starting from ideas and results given by Özkaldi, Ä°larslan and Yaylı in (2009), in this paper we investigate Bertrand curves in three dimensional dual space D3. We obtain the necessary characterizations of these curves in dual space D3. As a result, we find that the distance between two Bertrand curves and the dual angle between their tangent vectors are constant. Also, well known characteristic property of...

Author(s): Ä°lkay ARSLAN GÜVEN and Ä°pek AÄžAOÄžLU

May 2014

Angular symmetry of space-time and the spinor representation of Poincaré group

In the paper, a relativistic theory is suggested; we add three independent angles to the four coordinates of the Minkowski space that define the (x, t) - position of a moving local observer. These angular coordinates define the orientation of an observer under free rotations and they allow us to introduce the generators of the Poincaré group in the angular representation. Instead of a multi-component wave...

Author(s): R. A. Sventkovsky

May 2014

Modeling and simulation of watershed erosion: Case study of Latian dam watershed

The Latian Dam is one of the important drinking water resources of Tehran, and it also has a role in preventing the flood. It is very important to keep the quality of water and preventing the dam from filling. Considering the special aspects of RUSLE model, it was used for estimating the amount of erosion in the watershed of dam including the sub-basins: Jajrood River, Kond River and Afjeh River, and then compared with...

Author(s): Mirzai M., Sajadi A. and Nazari A.