the main objective of this research was the measurement of soil characteristics, land evaluation and determination of potential yield of sugar beet in yekanat plain of marand. for doing this, firstly, yield potential of sugar beet was estimated by fao method and secondly land evaluation of different soil units for sugar beet cultivation was determined by parametric method. results showed that m...

We performed mechanical tests on a matrix-free keratin model-hagfish slime threads-to test the hypothesis that intermediate filaments (IFs) in hydrated hard alpha-keratins are maintained in a partly dehydrated state. This hypothesis predicts that dry IFs should possess mechanical properties similar to the properties of hydrated hard alpha-keratins, and should swell more than hard alpha-keratins...

The Beverton-Holt theory of harvesting a multicohort fishery subject to constant recruitment, and the Leslie matrix harvesting model modified to include a nonlinear stock-recruitment relationship, are extended and shown to be related through the ultimate-sustainable-yield problem for an age-structured population. The well-known result that the optimal harvesting policy for the Leslie matrix mod...

In this paper, the stress concentration around a hole in the single layer composite materials with long fibers is examined. The single layer has an infinite length, limited with and instant thickness and is loaded by a constant tension force p at infinity. The width of the lamina is considered to be finite and bears a hole as a defect. Due to presence of excessive shear stress in the matrix bay...

Linearized methods are presented for appraising image resolution and parameter accuracy in images generated with two and three dimensional non-linear electromagnetic inversion schemes. When direct matrix inversion is employed, the model resolution and model covariance matrices can be directly calculated. The columns of the model resolution matrix are shown to yield empirical estimates of the ho...