conditional monitoring is prerequisite to prevent severe damage or falling down the trees. problems such as trunk decays, reduces trees resistance against wind and floods. in this study, a mathematical modeling technique is being selected to determine the trees strength against such events. finally, an applicable model for safety factor was created by having numeral (dimensions of crown and tru...

An approximate Steiner tree is a Steiner tree on a given set of terminals in Euclidean space such that the angles at the Steiner points are within a specified error from 120◦. This notion arises in numerical approximations of minimum Steiner trees. We investigate theworst-case relative error of the length of an approximate Steiner tree compared to the shortest tree with the same topology. It ha...

increasing energy demands associated with economic growth and industrialization have resulted in dramatic increases in air pollution emissions. air pollution damages the plant mainly by disrupting cell homeostatic conditions.in the present study, diverse plant criteria indicating air pollution from different levels including cell biochemistry, leaf and tree crown in the plane-tree were determin...

In computer graphics, models describing the fractal branching structure of trees typically exploit the modularity of tree structures. The models are based on local production rules, which are applied iteratively and simultaneously to create a complex branching system. The objective is to generate three-dimensional scenes of often many realisticlooking and non-identical trees. Our goal, instead,...

Theory and experiment on the London moment is reviewed. A simple mathematical model is motivated and then used to study the responses of a spherical superconductor to an external field and to rotation. It reveals a connection between perfect diamagnetism (Meissner effect) and the London moment. In the model neither of these are exact but the deviation from B = 0 internal field in the former and...

Theory and experiment on the London moment is reviewed. A simple mathematical model is motivated and then used to study the responses of a spherical superconductor to an external field and to rotation. It reveals a connection between perfect diamagnetism (Meissner effect) and the London moment. In the model neither of these are exact but the deviation from B = 0 internal field in the former and...

A geometric graph is a graph whose vertices are points in the plane and whose edges are straight-line segments between the points. A plane spanning tree in a geometric graph is a spanning tree that is non-crossing. Let R and B be two disjoint sets of points in the plane where the points of R are colored red and the points of B are colored blue, and let n = |R ∪ B|. A bichromatic plane spanning ...