this research was conducted to investigate the effect of planting space on fiber morphology of acer velutinum. in this work, from each treatment including planting space of 1×1, 1.5×1.5 and 2×2 meters, four trees were cut from shastkalateh plantation of gorgon university and factors such as length and annual diametrical growth of trees as well as length, diameter and wall thickness of fibers we...

knowing and conducting studies on size characters of trees is essential for assessing the tree volumeand/or other statistical parameters and also forest management. the characteristics of 529 treesincluding diameter at breast height (dbh) and total height were measured in an even-aged fraxinusstand for two periods from 2005 to 2012 in chelir district, a part of experimental kheyrud forest.resul...

Simple families of increasing trees have been introduced by Bergeron, Flajolet and Salvy. They include random binary search trees, random recursive trees and random plane-oriented recursive trees (PORTs) as important special cases. In this paper, we investigate the number of subtrees of size k on the fringe of some classes of increasing trees, namely generalized PORTs and d-ary increasing trees...

We study weighted path lengths (depths) and distances for increasing tree families. For those subclasses of increasing tree families, which can be constructed via an insertion process, e.g., recursive trees, plane-oriented recursive trees and binary increasing trees, we can determine the limiting distribution which can be characterized as a generalized Dickman’s infinitely divisible distribution.

We first show that increasing trees are in bijection with set compositions, extending simultaneously a recent result on trees due to Chapoton and a classical result on increasing binary trees. We then consider algebraic structures on the linear span of set compositions (the twisted descent algebra). A number of new Hopf algebra structures (neither commutative or cocommutative) and of enveloping...

We first show that increasing trees are in bijection with set compositions, extending simultaneously a recent result on trees due to Tonks and a classical result on increasing binary trees. We then consider algebraic structures on the linear span of set compositions (the twisted descent algebra). Among others, a number of enveloping algebra structures are introduced and studied in detail. For e...

We first show that increasing trees are in bijection with set compositions, extending simultaneously a recent result on trees due to Tonks and a classical result on increasing binary trees. We then consider algebraic structures on the linear span of set compositions (the twisted descent algebra). Among others, a number of enveloping algebra structures are introduced and studied in detail. For e...