The objective of present study was to derive the economic values for number of inseminations to conception, calving interval, milk yield and stillbirth, using economic data of 10 Iranian Holstein herds. The economic values were derived by using the profit function methods and differentiating a profit equation with respect to the traits of interest. The cow fertility costs herd amortization or r...

to estimate heritability and genetic trend for 305-d milk production and lactation persistency, a total of 130,668 monthly test day milk yields belonging to 15,183 first lactation holstein cows in 131 herds and calved from 2000 to 2009 were used. to calculate 305-d milk yield as well as lactation persistency, estimated parameters of wilmink’s exponential function were applied. the parameters of...

in this research, in order to describe milk production traits lactation mahabadi goat breed, seven statistical functions were fitted using 1665 milk production traits records and 833 body weight records. the milk production traits were milk yield, fat percent, fat yield, protein percent, protein yield, lactose percent and snf percent. these records have been recorded on 123 goats during years o...

abstract in this study, seven main field crops of the rudasht and abshar irrigation networks of esfahan (with 54,000 ha designed command area) such as wheat, barley, onion, sunflower, fodder mays and sugar beet were selected and swap model was calibrated by inverse modeling base on field experiments results in order to determine crop water salinity production functions. field experiments were c...

In this research the stress-strain curve of porous Titanium, as a common material for biomedical application, was predicted using the mechanical properties of fully solid Titanium experimental data. Modified Gurson model (Gurson-Tvergaard-Needleman (GTN) model) was used to predict the plastic response of porous Titanium in compaction. Different values of GTN parameters were used for different i...

A solution technique for the dynamic analysis of asymmetric base-isolated buildings, subject to earthquake ground motion, is presented. To develop the formulation, a yield surface as a function of both shear force and torsion moment of the sliding surface with rigid perfectly plastic behavior is constituted. To achieve the objective, the yield stress is defined by the friction coefficient throu...

Elastic-plastic behavior of a beam made of functionally graded material is investigated in this work‎. ‎The beam is subjected to the constant axial and bending loads and the critical values of these loads for yield‎, ‎collapse and elastic-plastic conditions are obtained‎. ‎The variation of elastic modulus and yield strength through the height of the beam is determined with an exponential rule‎....