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Visen et al [4] proposed a different approach to segment occluding groups of grain kernels.
When these images are eroded, the touching rice may not be segmented, this will result in the counted number is smaller than the corresponding number.
Bulley: Digital image analysis for software separation and classification of touching grains: I.
Paliwal, et al: Identification and segmentation of occluding groups of grain kernels in a grain sample image.
Symons: Seed sizing from images of non-singulated grain samples, Canadian Biosystems Engineering.

At the primary stage of tensile test, these strengthening phases fracture (Fig. 3(c)) and large number of micro-cracks appeared on the Al matrix (Fig. 3(d)).
According to Fig.4, there are a larger number of tiny dimples on fracture surface (Fig.4 (a)), and the shape and sizes of tiny dimple from the magnified image (Fig.4 (b)) of a fracture could be clearly observed.
The fracture mode of extruded 1420 Al-Li alloy depends on the different strength between grain boundary and grain matrix.
When the strength of grain boundary is higher than the matrix, fracture grows and extends in the grain matrix, so the fracture mode of this alloy is transgranular fracture.
There is no balance phase after aging treatment on the grain boundary, and these cracks appear, and grow preferentially in the grain matrix, so the fracture mode of this 1420 alloy is transgranular, and based on the analysis results, the fracture mode of the alloy is ductile transgranular fracture[7].

Introduction With the development of the western regions in recent years, large numbers of roads, railways and other infrastructures have to be constructed in the desert area and the sand is the only source for construction.
physical Properties Grain Composition.
The diameters of the grains mostly range from 0.25mm to 0.074mm.
Natural density of wind-blown sand is mainly related to the grain composition and the degree of sorting.
The regression equation can be written as φ=aρ+b where a and b are related with grain composition.

Repeatedly quenching decreases prior austenite grain size and enhances the fatigue toughness [1-3].
Santos et al. reported that repeatedly induction heating decreased prior austenite grain size and refined martensitic structure in AISI 52100 bearing steel [4].
The objective of this work is a clarification between the relationship between the quenching number and retained austenite amount.
As a number of quenching times increases, the Vickers hardness increases ranging from 1.0mm to 1.5mm.
Kida, Effect of twice quenching on prior austenite grains and rotating bending fatigue in SUJ2 steel, Applied Mechanics and Materials, Vol. 620, pp. 443-448, (2014)

Also, the number of electrons in the plasma discharge increases with increase in pressure.
Interestingly, a distinct elevation from the grain center (nucleation site) toward the grain edges can be observed.
The grain centre starts from point C to the grain edge.
The grain center and grain edge are shown by C and D arrow, respectively.
Elevation from grain center (C) towards grain edge (D) show that the small grain has lowest elevation (11.57 o ).

The grain size is refined and grain boundary and dislocations are increased after treatment.
This increase the number of the nucleation nitrides.
The more fine the grain size, the more boundaries of grain size located in the unit volume.
The brittleness of nitriding layer decreased with the increase of numbers of γ′.
Third, the toughness has relationship with grain size.

Large number of research works are found reported on FSW various grades of steels such as plain carbon steels, alloy steels and stainless steels.
A few number of initial FSW trials were carried out to find the FSW parameters combinations and to produce sound joints.
Referring to Figure 4 (a), It can be seen that the base metal has a cold rolled coarse grained annealed structure with an average grain size is about 30 µm.
Further, there is considerable refinement of grains in the stir zone with an average grain size of 4-7µm.
The mechanism of is that at a critical strain, difference in the dislocation along the grain boundaries provide the driving force for nucleation of new grains which are strain free [6].

Thereby each grain boundary contributes ~3.2V to the total switching voltage of a given protection device.
The neutron time-offlight method itself has the advantage to allow a number of peaks, or even different phases, to be analysed at the same time.
To learn more about the actual stress state of varistor material, comparative tests with a number of ZnO-blocks with different thermal history should be analyzed.
With an average grain size of ~15 µm, a quite good grain number statistic has been achieved.
This may be caused by temperature gradients during the sintering and grain growth process of the ceramic.

The subscripts n , n-1, n-2, and i are the number of iteration.
To make clear the effectiveness, we used a grain oriented silicon steel sheet as a sample sheet instead of a non-oriented silicon steel sheet.
As shown in these figures, x- and y-components showed the different numbers of iteration.
The y-direction corresponds to the transverse direction and the hard magnetizing direction of the grain oriented silicon steel sheet.
In comparison of numbers of iteration until the flux conditions are satisfied, the number of iteration of I-PD, IP-D, PID, and P increased in turn.

At present, the researchers at home and abroad have proposed a number of protective measures to reduce the harmness caused by the high temperature steam oxidation, three of which are most representative, as following: (a) improving the contents of Cr, Si, Al and other alloying elements in materials; (b) Cr-plating treatment on the surface of materials; (c) chromate treatment and special heat process to obtain finer grain tissue.
After shot peening treatment of the steels, the fragmentation of inner surface grains occurred, and also the surface dislocation density increased.
When the materials was heated, the solute atoms transformed into gaseous solute atoms ,which transferred to the grain boundaries, thus smaller grain boundaries or sub-grain boundaries were produced.
The newly formed grain boundary would provide diffusion channel and driving force for Cr, promoting the formation of a protective oxide film.
Through shot peening treatment, a cold work hardened layer with a certain thickness occurred on the Super304H steel surface, which could significantly improve the dislocation density on the specimen surfaces, and also make the subgrain within surface layer fragmentation, thus causing the formation of a large amount of austenite grains, dynamic recrystallization grains and a large number of slip bands.