rainfed wheat is the main source of staple food for people in the developing countries. various factors contribute to and affect the production of this crop. the aim followed in the present study was to develop a model to estimate rainfed wheat grain yield as based on physico-chemical properties of the soil. therefore, wheat grain yield and soil physico-chemical properties were separately deter...

We consider three different non–overlapping germ–grain models, two of which are constructed in a similar fashion. These two models are generalisations of Matérn’s hard–core models. In both cases we start with a homogeneous Poisson process and use the points as centres of convex sets, grains, of the same shape. The process is thinned so that no grains overlap. Two different thinning schemes resu...

We develop a phase field model to study the phenomenon of recrystallization and grain coarsening in polycrystalline material. A unique feature of our model is that it can time-evolve the actual orientation field of a material, expressed in terms of quaternions, a four-dimensional non-conserved vector field. The quaternions evolve in time following a Langevin dynamics. The free energy that drive...

among the food products, grains play an important role in the consumption patterns of people, especially in the developing countries. since iran's main source of public dietary energy comes directly from grains, investigating and identifying the determinants of import of these products can be an important step towards food security. most experimental studies consider import of grains as only a ...

Wepresent first-principles simulations of single grain boundary reflectivity of electrons in noble metals, Cu and Ag. We examine twin and non-twin grain boundaries using nonequilibrium Green’s function and first principles methods. We also investigate the determinants of reflectivity in grain boundaries by modeling atomic vacancies, disorder, and orientation and find that both the change in gra...

This paper uses a multivariate vector error-correction generalized autoregressive conditional heteroscedasticity model to investigate the effect of British grain prices on their Irish equivalents. We find that in the long run the law of one price holds and in the short run the model captures the salient features of Irish grain prices. The model is used to compute rolling forecasts of the condit...

This paper attempts to determine the mechanisms governing the grain growth process that occurs during lamination annealing of a cold-rolled, motor-lamination steel. A new simulation approach linking a Monte Carlo model, with EBSD scans used as input, has been employed to incorporate the effects of crystallographic texture on the simulated grain growth process. The results from the texture analy...

A phase-field approach for quantitative simulations of grain growth in anisotropic systems is introduced, together with a new methodology to derive appropriate model parameters that reproduce given misorientation and inclination dependent grain boundary energy and mobility in the simulations. The proposed model formulation and parameter choice guarantee a constant diffuse interface width and co...

APSIM Nwheat is a crop system simulation model, consisting of modules that incorporate aspects of soil water, nitrogen (N), crop residues, and crop growth and development. The model was applied to simulate aboveand belowground growth, grain yield, water and N uptake, and soil water and soil N of wheat crops in the Netherlands. Model outputs were compared with detailed measurements of field expe...

Ultra-high purity alumina was sintered in hydrogen at temperatures ranging from 13251 to 20201C. Normal grain growth was maintained in all samples and grain boundary mobilities were measured. The data represent the most complete measure of intrinsic grain boundary mobility for alumina grain growth currently available. There are two orders of magnitude of discrepancy between the calculated and m...