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The mathematical model of grain drying plays an essential role in developing grain dryer structure and obtaining the drying technological parameters.
It is very important to establish an accurate mathematical model for predict the grain germination rate and moisture content in the grain drying process.
The achievement is using real-time measured data from sensors to provide a large number of measured data for the simulation system, and adjusting the prediction for the further production process.
Complexity analysis and process control for grain drying[D].
A model-predictive controller for grain drying[J].

The initial grain structure was equiaxed, but at low strains the grains become elongated in the torsion direction.
The origin of the increased complexity is from the number of possible events that can occur during deformation: austenite softening, ferrite softening, and deformation stimulated transformation.
There are a number of incomplete grain boundaries, i.e. isolated high angle grain boundary segments present in the larger ferrite grains.
Ferrite grain size and aspect ratio The changes in the ferrite grain size and grain aspect ratio, measured by linear intercept method, are shown in Fig. 5 at different strain.
Then with increasing strain from 1.5 to 2 ferrite grain size and grains aspect ratio simultaneously decrease.

The hot deformation has a critical influence on the number of packets that forms.
Group Number Variants Number {111}γ plane Group 1 1,2,3,13,14,15 (111) Group 2 5,6,7,16,17,18 (-1-11) Group 3 8,9,10,19,20,21 (-111) Group 4 10,11,12,22,23,24 (1-11) Table 1: The 24 KS (or GT) variants and their partition into four groups.
The variant numbers are based on [4].
The reconstructed EBSD maps of 2 prior γ grains of sample 0.2 (grain 1) and sample 0.8 (grain 2) are represented in figures 3a and 3b, respectively.
However, the hot deformation is shown here to have a critical influence on the number of groups that forms.

The number of the striations observed in the colloidal crystal under crossed polarized light decreased at some parts in a growth container after the additional centrifugation, while the number also increased at the other parts.
In this study, we tried to reduce the number of stacking disorders in colloidal crystals by centrifugation.
The number of striations in a grain decreased after the above gravitational annealing process (Fig. 4).
The number of striations in another grain increased after the same gravitational annealing process (Fig. 5).
We should collect much more data, and clarify the correlation between the directions and the number of striations in future.

In this study, HPT is adopted for grain refinement and subsequent aging is conducted at reduced temperatures.
Results and Discussion The Vickers microhardness increases with an increasing distance from the disc centre and with the increasing number of turns as shown in Fig. 1a.
At the last stage where the hardness is saturated, the grain has been further refined.
The TEM observation in Fig. 2 thus shows that grain refinement is developed with increasing amount of deformation.
TEM observation reveals that the grain size was refined to ~200 nm at the saturation. 4.

The recrystallization of the material can be considered to be a number of processes that correspond to two separate stored energy release peaks.
At the same time, some elongation of grains occurred in the matrix.
Elongated matrix grains appeared because of the reduction of the dislocation density and annihilation of some low-angle grain boundaries (LAGBs) between chains of subgrains located in layers parallel to the sheet plane.
LAGBs in the elongated thin matrix grains created a rather poorly developed subgrain structure.
The recrystallization peaks are marked in the Fig. 2 with numbers 1 and 2.

The yield stress and the fracture stress increase with decreasing grain size.
The effect of grain size on the yield stress of magnesium and its alloys has been reported in a number of studies, e.g. [4-10].
The yield stress and fracture strength increase with decreasing grain size.
The grain size dependence of the yield stress σy can be expressed according to the Hall-Petch relation: σy = σ0y + kyd -1/2 (1) where d is the grain size, σ0y and ky are constants.
Strength and fracture of magnesium alloys is influenced by grain size.

The average grain size varied between 0.1 and 0.2 µm.
On the right the calculated energies per H atom of a number of H complexes in c-Si are show [11,12].
Defect passivation requires only a small fraction of H atoms, which is equal to the number of passivated Si dangling-bond and amounts to about 3.7×10 18 cm-3.
Platelets neither penetrate the sample surface nor grain boundaries because of band bending caused by high concentrations of surface and grain-boundary defects [16].
Therefore, its formation is restricted to intra grain regions.

The effect of condition on the grain boundary is numerically discussed.
The velocity gradient is additively decomposed into the non-plastic and plastic parts. . (1) The plastic part of velocity gradient is given by . (2) is the number of slip system, and a variable with the superscript denotes the value of a specific slip system .
In the case 1, is applied on the grain boundary, corresponding that dislocations cannot penetrate the grain boundary.
In the case 2, is subjected to the grain boundary.
In this case, dislocation cannot penetrate the grain boundary and piles up, resulting the strain gradient arises at a nearby grain boundary.

It is concluded that the fine ferrite grains or austensite grains are stabilized by the grain boundary carbides, and grain-boundary sliding controlled by grain boundary diffusion is the principal superplastic deformation mechanism at temperatures in the range of 700-850 °C.
The average grain size is 4.5µm, which is approximately equivalent to the initial grain size; and the grains retain nearly equiaxed as the initial grains (Fig. 1(b)).
I.e. dynamic grain growth had not occurred during testing in this case, whereas grain growth occurs for the cases of very-fine-grained UHCS superplastic deformation in most other studies [4-5].
The grain-boundary carbides are coarsened (comparing Fig. 1(b) with Fig. 1(c)), with resulting average size of 1.5µm; the intragrain carbides partly dissolve, and the number of carbides decrease.
It can be concluded that the grains are stabilized by the largeish grain boundary carbides.