the establishment and survival of seedlings is one of the main objectives of forest management which ensures continues production. the aim of this article is the investigation of dead trees effect on beech and hornbeam seedlings in masal's forests. for this reason, 30 dead trees were selected, and the control trees were selected in four aspects around the dead trees. they were the same as ...

the parallel systems are special important types of coherent structures and have many applications in various areas.in this paper we consider a two-exchangeable-component parallel system for the generalized farlie-gumbel-morgenstern (generalized fgm) distribution. we study the reliability properties of the residual lifetime of the system under the condition that both components of the system ar...

In this study two actual types of problems are considered and solved: 1) determining the maximum common connected fragment of the T-tree (T-directed tree) which does not change with time; 2) determining all maximum common connected fragments of the T-tree (T-directed tree) which do not change with time. The choice of the primary study of temporal directed trees and trees is justified by the wid...

abstract background: the current practice to measure rv is either by bpg or helium dilution methods which may not be available in all clinics due to their cost. methods: this paper outlines a method for both direct and indirect calculation of rv via pft with acceptable sensitivity (81 %, 60% ), specificity (71 %, 94%) and validity (76%, 78%) for obstructive and restrictive lung disease respecti...