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., Lutsk, Ukraine, 43018 aruban_artem1979@ukr.net, bShyberko@ukr.net, chuliieva@lntu.edu.ua, Keywords: 3D modelling, particle distribution, powder materials, porosity, coordination number, properties, initial parameters, powder size and shape.
An example of visualization of the developed software product for filling material particles is given, taking into account a number of cross-sections of a cylindrical hopper in height.
Basic parameters of the powder filling process Hopper type Hopper size H×D, [pixel)] Angle, [α°] Particle diameter, [pixel] Porosity [%)] Average coordination number * Cylinder 500×500 10 18 21,1 0,34 *– average data from 10 ÷ 20 backfills.
That is, to get data on the average number of contacts (connections) of particles with neighbouring components.
In calculations, n-th is the number of particles in the range of radii equal ri to rj related to the average ris, that is, it fully satisfies the following condition: Qn = h(r).

The main toughening mechanisms of the composites were deflection and bridging of the crack as well as grains’ pulling out.
Meanwhile, with the increase of Ni, the density of materials increased gradually, and the grain size also decreased, which was the main reason for the increase of bending strength.
At the same time, the microstructure of the materials became more homogeneous, and the number of holes formed by the pulling out of grains increased.
A large number of short rod-like titanium diboride were pulled out, this would consume more energy while the crack propagating, thus improved the fracture toughness of the composite materials effectively.
Due to the accession of Ni powder, the density of the composites was increased, the formation of short rod-like grains was promoted, and the fracture toughness was improved greatly. 2) The main toughening mechanisms of the composites were deflection and bridging of the crack and pulling out of grains, etc.

Thus, it usually provides the cast materials with spherical grains.
The solidification microstructures were primarily consisted with primary α grains and eutectics at intergranular boundaries.
At higher pouring temperature, only limited number of α grains is likely to exist initially in the flowing bulk melt due to re-melting of chilled grains separated from the cooling plate.
At larger angle of inclined cooling plate, on the other hand, insufficient number of α grains is likely to separate out of the chill substrate and entrain in the flowing bulk melt due to a short contact time between the cooling plate and the flowing melt.
�ˆP �‰P effect on the number of initially formed grains: 620� as a pouring temperature and 20 degree as a cooling plate angle, followed by the water quenching.

The microstructure results revealed the appearance of plate-like grain.
Compared with the BIT-N and BIT-W materials, the BIT ceramics represented intergranular and transgranular fracture because of the porosity formation in the interior of the grains and grain boundaries.
With the plate-like grains ~ 4µm diameter and ~ 0.5µm thickness, the platelets of Fig. 2 (b) and (c) were smaller than observed in Fig. 2 (a) indicating the grain growth inhibited by the donor doping.
According to the electronic conductivity relationship µσ nq= (1) where n is the number of the carriers, q the charge and µ the mobility, it was thought that the number of the hole carriers, n, was decreased.
The donor doping controlled the growth of plate-like grains.

On the basis of experimental data the number of nuclei was approximated by an equation of the form 2TN N∆= µ , where Nµ is a growth constant.
The growth of spherical eutectic grains was calculated with the JH model modified by Tiller for spherical grains.
The instantaneous average lamellar spacing was calculated as ** /2 NrGrπλ = , where r* is the instantaneous grain radius and N* is the instantaneous number of graphite lamellae on the grain circumference.
At the end of the solidification process, an average lamellar spacing defined at the level of the whole grain, λ avGr, can be calculated as: Eq. 9 ( )[ ]∑= − ∆ = n i i Gr t av Gr tdtdr r 1 * 1 λ λ where tr is the total radius of the eutectic grain, dtdr* is the growth rate of the grain during the time-step i, t∆ is the duration of the time-step i, and n is the total number of time-steps required for eutectic solidification in the considered volume element.
They include a large number of adjustable parameters and require extensive calibration.

In order to solve these disadvantages, a coarse-grained parallel genetic algorithm(PGA) based on personal computer cluster was proposed to inverse S-wave velocity structure of shallow soil layer of actual engineering sites, the simulated annealing algorithm and parallel technique message passing interface(MPI) were adopted to implement the coarse-grained parallel compute.
Theoretical analysis shows that the binary encoding method can receive the maximum number of models and it is easy to implement in genetic operation.
If Qi>Pi，then the discrepant number will increase to individual; if QiThe coarse-grained parallel genetic algorithm is adopted in this paper, the phase velocities of Rayleigh wave and Love wave of layered soil is calculated by the main process (the process identification is 0) and it also reads the initialize parameters of genetic algorithm then transfers the initialize parameters to slave process.
Simulated annealing algorithm and parallel technique message passing interface(MPI) are adopted to implement the coarse-grained parallel computer, in order to fully use the computer efficiency, the subpopulations were collaboratively optimized through individual migration strategy and the dynamic populations were adopted to balance the computing load.

Grain Size Distribution Analysis.
Grain Size Distribution Analysis.
When the grain is too large, it does not mix properly with the other grains in the batch, while if the grain is too fine, it creates air bubbles in the final glass product.
If the silica grain has a uniform shape, it can be more densely packed together and reduce the number of voids, increasing the density of the sand and increasing its specific gravity.
To expand the number of possible uses in the glass industry, further processing is recommended to increase the SiO2 content and decrease the content of Al2O3, Fe2O3, TiO2, CaO, and MgO.

The grain structure is columnar with one grain over the film thickness.
The quality of the fit is quite poor for the smallest thickness due to the limited number of points and to the dispersion.
The effect of the width observed by Espinosa et al. [14] is probably related to a similar small number of grains along the width
No dependence of the fracture strain on the film thickness is observed (though the number of data is too small relative to the scatter to ascertain definitive conclusions).
Minute amount of impurities segregated along the grain boundaries can also lead to much smaller grain boundary cohesion.

Up to now, there are a great number of publications reported that the ZnO thin films grown onto the silicon, sapphire and glass substrates [10-12], but there are scarce reports described that the ZnO thin films grown onto the Ni layers.
The spindle-like ZnO grains extended gradually during the temperature elevated, as show in Fig. 2a and Fig. 2b.
When the temperature up to 883 K, the whole grains unwrapped but a lot of gaps between grains and Ni layers still exist, as depicts in Fig. 2c.
Fig. 2f illustrates the transition process of grains morphology during thermal annealing treatment.
The formation of large relatively defect free grains resulted in dislocation sources.

Firstly, the rule that grain size of grinding wheel influences grinding surface roughness accords with general grinding theory, that is, small grain size of grinding wheel gets better grinding surface.
But the rules that grain size of grinding wheel and grinding pressure influence grinding efficiency don't accord with general rules.
Grinding efficiency of large and small grain size are higher than that of middle grain size.
Rotational speed's influence is the largest, grain size's is smaller and grinding pressure's is the smallest.
The best value combination of the three influencing parameters is: rotational speed 2500r/min (20.6m/s), grain size 9µm and grinding pressure 2.5Pa (75N).