this research has been done with the aim of explaining environmental and managerial factors that affects on rangeland vegetation distribution in saral rangelands of kurdistan province. after selecting plant types as working area were done sampling from plant types and determined some of plants parameters such as kind and number of plants and cover percentage. various environmental factors such ...

The stress distribution on the tip of the cracks and the stress intensity factor on them are the main courses in the fracture mechanic. The stress intensity factor of the cracks with the different load exited and the different geometry are listed in the tables of the standard books. In all of them, the cracks are located in the central point of the plates. In the uniform edge loaded case, the c...

in this paper, the effects of reflected waves of the facets on the internal optical intensity of semiconductor dfb lasers are investigated. the uniformity of optical intensity along the cavity length is evaluated with flatness parameter. the dependence of this parameter on coupling coefficient, reflectivity and grating phase at the facets is also studied. this investigation shows that in some s...