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PSO-Grain BP ANN.
An improved PSO defined as PSO-Grain was proposed here to optimize the λ value.
A hybrid BP ANN with PSO-Grain algorithm was developed.
For PSO-Grain BP ANN, a training process was divided into two steps.
After testing by the software program, number of the hidden units was determined as 4.

In this study, Al-Mg alloy plates with three kinds of crystal grain sizes were used.
In the case of large grain size, 3000μm, the strain concentration occur at a certain specific crystal grain in early stage of plastic deformation shown in Fig4(b).
But, the grain size become large, the order of the strength turns over as shown in Fig.5(c).
That of grain size d=42μm also shows the similar tendency.
The crystal grain boundary shape was approximated by Voronoi multi-divisional model.

(4) where R is dendrite tip radius, Γ is Gibbs-Thomson coefficient, Pei is Peclet number, mi is liquid slope,C0,i is initial concentration, ki is partition coefficient, ζc(Pei) is function of Peclet number, Iv(Pei) is Ivantsov solution (where subscript i=Cr or Al), Ghkl is temperature gradient along the crystallographic orientation.
Three typical weld defects, severe stray grain formation, centerline grain boundary formation and asymmetrical solidification cracking, are simultaneously mitigated to improve weld quality.
Stray grain formation in welds of Ni-based superalloy CMSX-4.
Stray grain formation in single crystal Ni-based superalloy welds.
Analysis of stray grain formation in single-crystal nickel-based superalloy welds.

In our previous studies, we proved that during abrasive machining the metal microvolume affected by abrasive grains accumulates energy.
A number of studies [3, 4, 5, 6, 7, 8, 9, 10, 11, 12] are devoted to the issues of metal machinability by abrasive tools.
Dyakonov has undertaken a number of studies that established a correlation between material machinability and the types of abrasive machining, processing restraints, and process system parameters.
We [26] proposed a method simulating the behavior of multiple abrasive grains in a grinding wheel.
It was experimentally proved that the number of measurements of the specific energy of metal dispersion by abrasive grains with various compositions and grain sizes does not exceed 10.

For development of special thermo-mechanical treatment conditions of low-alloy, low-carbon steels which would provide maximum possible crushing of a structure a detailed information was obtained from previously carried out investigations about the influence of austenitic grain size and degree of this grain fragmentation upon kinetics of phase transformation, type and quantitative characteristics of bainitic-martensitic, ferritic-bainitic and ferritic structures.
For low-carbon ferritic shipbuilding steels it has been determined that final (finishing) plastic deformation of rolled sheets and plates should be carried out close to, and completed a little bit below a point Ar3, what allows for formation of a maximum possible number of ferrite germs on austenitic grains boundaries as well as formation of a developed substructure in ferrite due to its deformation.
Dispersed carbides of MeC type, about 10 nm in size, are evenly distributed over grains body.
a) b) Fig. 3 Fine structure of steel 06Mn"iV"B after special thermol-mechanical treatment: a) granular bainite b) ferrite Investigations have shown, that after plastic deformation of unrecrystallized austenite at temperature lower than recrystallized austenite temperature, number of dislocation boundaries in granular bainite increases, ά-phase areas are broken into misoriented fragments.
Formation of ultra- fine-grained and submicrocrystalline structures is provided by carrying out control over size of grains and subgrains in the course of technological processing, as well as over correlation and morphology of structural components at stages of heating up before rolling or heat treatment, at plastic deformation and in the process of phase transformation at cooling. 2.

The grain size of the sulfides is generally 0.01-0.03 mm.
In the overwhelming number of cases, bornite, as set Shneyderhёn [2] has a variable, but generally weak anisotropy.
Covellite is grain size of 0.005 to 0.03 mm, small clusters of up to 0.05 mm (Fig. 7).
The grain size of the sulfides is mainly 0.01-0.03 mm.
All sulphides are located within the host rock grains.

The main changes in microstructure caused by Ca addition were the grain refinement in the as-cast alloys and the formation of new Al2Ca phase along the grain boundaries.
Grain size was also measured by the linear-intercept method.
The grain size decreased significantly from 200µm in AZ91 alloy(a) to about 110µm(c) with increasing Ca content.
Thus it can be concluded that with the addition of Ca, two microstructural changes can be observed: First, the grains of the matrix were finer than those of AZ91 alloy.
Second, a large number of Mg17Al12 disappeared and a new Al2Ca phase was formed as shown in Fig. 2(b).

Fig.2, The grain size value calculated at different sputtering pressure.
The crystallinity of the ITO nanocolumns can be evaluated by grain size.
The most distinguishable nanostructure grains are observed at high sputtering pressure.
The average nanostructures grain size between of 25 – 35 nm.
Acknowledgement This work was supported by University Malaya Research Grant (UMRG) under project number RG141-11AFR and Exploration Research Grant Scheme (ERGS) under project number ER012-2011A.This work also supported by Ministry of High Education (MOHE) High-Impact Research (HIR) Grant under project number F000006-21001.

The results indicate that some number of large,coherent precipitates prevents serrated flow by way of trapping vacancies, but small precipitates content do not supress it. 1.
Microstructures of the alloys are identified by the presence of continuous equiaxed grains whose size is about 18-50 mm.
More number of grain boundaries is seen with continuous precipitates in the 16h aged specimens( fig.1d).
A large number of coherent precipitates prevents serrated flow by way of trapping vacancies[9,10].
A number of big, coherent precipitates prevents serrated flow by way of trapping vacancies. 4.

Recently, a large number of researches focus on Bi0.5Na0.5TiO3 (BNT)- and K0.5Na0.5NbO3 (KNN)- based lead-free piezoelectric ceramics[2].
To improve its piezoelectric properties, a large number of BNT-based solid solutions, such as BNT-Bi0.5K0.5TiO3 [4], BNT-NaNbO3 [5] and BNT-Bi0.5K0.5TiO3-BaTiO3[6], have been studied intensively.
Obviously, a preferred grain orientation of (h00) happened.
The vacancy and chemical deviation would hamper the orientation of grains.
In the early period, a large number of grains with a small size could be observed except for some templates with a large size, which proved that the growth of matrix powders along the templates did not take place sufficiently.