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When uses the running mean method carries on the data smoothing, an important question is how determines the smooth time number (n).
If the sequence is quite smooth, and has the autocorrelation, by now used the small smooth time number to be able to obtain the good smooth effect; If the sequence fluctuation is big, and does not have the autocorrelation, by must use the big smooth time number to be able to obtain the good smooth effect.
This research acts according to these two commonly used principles, and unifies the massive case study, had determined following three suit the food production potential forecast the smooth time number definite method.
The entire province grain total output data origin was 1983 to 2010 altogether 27 year grain total output data.
Note: Heilongjiang Province education department science and technology financing projects,Project number：11531259 References: [1] Tanksley,S.D.

Table 1 Austenite grain size and pearlite size of industrial U75V Sample number Steel grade Average grain size (μm) Austenite grain size grade (grade) 11# U75V 11.704 9.0 51# U75V 13.481 9.5 Fig. 1 Austenite grain size of 11# Fig. 2 Austenite grain size of 51# The austenite grain size of industrial U75V rail was 9.0 grade by means of sampling, semi-quenching, processing and inspection analysis. 2 High Temperatures Confocal The variation of austenite grain size of high carbon rail steel had been visually revealed by using different insulation temperatures for U75V rail specimens.
Table 2 High temperature confocal test results of U75V rail specimens Number Steel grade Insulation temperature (℃) holding time (s) Austenite grain size (μm) Austenite grain size (grade) 1 U75V 1300 180 164 2.5 2 U75V 1200 180 137 3.0 3 U75V 1100 180 146 2.5 4 U75V 1000 180 117 3.5 5 U75V 900 180 30 7.0 1200℃, 180s 1300℃, 180s 1000℃，180s 1100℃，180s Figure 3 1 # Metallographic photograph Figure 4 2#Metallographic photograph Figure 5 3 #Metallographic photograph Figure 6 4 #Metallographic photograph 900℃，180s Figure 7 5# Metallographic photograph The formation process of austenite included nucleation, growth, dissolution of Fe3C and homogenization of A.
The growth of austenite grain is carried out by grain boundary migration.
Small grains are shrinking, large grains are growing, then large grains eat small grains.
Table 3 Rail heating process and corresponding austenite grain size in laboratory Sample number Steel grade Insulation temperature (℃) holding time (min) Austenite grain size (grade) 1 U75V 900 30 6.5 2 U75V 1000 30 4.5 3 U75V 1100 30 3.5 4 U75V 1200 30 2.0 5 U75V 1300 30 0.5 6 U75V 1000 10 6.0 7 U75V 1000 50 5.5 　 Figure 8 Grain morphology of 1#　 Figure 9 Grain morphology of 2# 　 Figure 10 Grain morphology of 3#　 Figure 11 Grain morphology of 4# Figure 12 Grain morphology of 5# Figure 13 Grain morphology　of 6# 　Figure14 Grain morphology of 7# Temperature (℃) Figure 15 Effect of holding temperature on austenite grain size grade Figure 16 Effect of holding time on austenite grain size It can be seen from Figure15 that austenite grain size grade of U75V rail steel decreases and austenite grain gradually coarsens when the holding temperature rises from 900 to 1300.

Specimen number Yield trength/MPa Tensile strength/MPa Yield-strength ratio 1 600 665 0.90 2 530 670 0.79 Grain boundaries misorientation distribution.
Pipeline steel is a polycrystalline material system, composed by a large number of grains with different orientations and boundaries with different types and structures.
But after yield and in the process of growing up of the grain boundaries, the strain energy will concentrate in the small number of large-angle grain boundaries edge, the capacity of coordination to resist deformation will be weakened, resulting in the quick rupture after yield in the macro-performance.
Fig. 3 Interaction modes of PSBs with large- and low-angle GBs The PSBs through the low-angle grain boundaries does not mean it disappears, instead, it passes to the adjacent grain boundaries, and if there were still low-angle grain boundaries, it will continue to migrate until meet large-angle grain boundaries and pinned up in it.
Therefore, if the specimen has a larger percentage of low-angle grain boundaries, due to the difficulty for defects and stress to concentrate on the low-angle grain boundaries, the defects and stress will be pinned up in a small number of large-angle grain boundaries after reaching the yield stress.

There are a number of relations between various types of boundaries [2].
For a large number of random grain boundaries which can be thought of as uniformly distributed points in the five-dimensional space, the fractions are related to total volumes of spaces bounded by specified limits surrounding points corresponding to, respectively, ideal tilt, twist, symmetric and improperly quasi-symmetric boundaries.
Maximum relative uncertainties of these integrals are estimated as N -1/2, where N is the number of sampling boundaries falling in the volumes.
Symmetric boundaries, which have the most particular geometry occur extremely rarely, but the number of improperly quasi-symmetric boundaries is of the same order as the number of twist boundaries.
It has been confirmed that the amount of geometrically characteristic boundaries among random grain boundaries decreases with the decrease of the number of point group symmetry operations.

The cyclic hysteresis loops of UFG Cu shows the tension and compression peak stresses decreased gradually with number of cycles.
The low cycle fatigue behavior was found to be worse than coarse grained material while the high cycle fatigue behavior was reported to show remarkable improvement over coarse grained sample.
The grain refinement is apparent when compared to ~50 μm of the initial grain size prior to ECAP.
The tension and compression peak stresses decreased gradually with number of cycles.
After the first cycle, tension and compression peak stresses were shown to decrease gradually with number of cycles.

Ultra Fine-grained 6wt% Manganese TRIP Steel Seawoong Lee1, a , Kyooyoung Lee2, b , B.
An ultra-fine grained microstructure with a grain size less than 1μm was obtained.
Fig, 6 shows a stem image which is used to calculate mean grain diameter.Assuming the total volume fraction of each grain was not changed by the annealing, the average grain diameter was calculated by counting the number of grain boundaries intercepted by a straight line across stem micrographs.
Using equation (1) in the transverse and normal direction :     xM L L (1) Annealing temperature(℃) Fraction by XRD [%] Fraction by Magnetic saturation [%] 640 20 23 660 15 16 680 30 33 Where M is magnification, L is the total line length in calculated direction andx is number of points intercept grain boundaries, the average grain diameter was calculated.
An ultra fine-grained microstructure with grain sizes of 0.1 to 0.2μm was achieved by a short, low temperature isothermal hold.

Bulk metallic materials possessing uniform grain structure with average crystallite sizes below 100 nm and grains limited by high-angle boundaries can be formed by a number of methods [3, 4].
The data of the statistical analysis calculated from the grain size distributions of Nb3Sn layers in composites with different modes of doping with Ti after the first annealing (the set numbered from 1 to 5) are presented in Table 1.
Parameters of these structures after the two-staged annealing are presented as well (denoted by the numbers from 1¢ to 5¢).
In addition, it should be noted that strong relationship between the mean and the standard deviation allows to reduce the number of independent parameters at modeling of the microstructure evolution.
Plasticity and grain boundary diffusion at small grain sizes, Adv.

SAD patterns of the alloys processed by 3 or 4 ARB cycles show increased number of diffused spots.
As the number of the ARB cycle increases, the grain boundaries became better defined and sharp; the number of poorly defined boundaries, the extinction contours, and the dislocation density inside the grains decreased.
Sliding wear rates of the ARB-processed Al alloys are plotted against number of ARB cycles in Figs. 3 and 4.
Variation of wear rate of the ARB processed 5052 Al alloy as a function of number of ARB cycle. 0 1 2 3 4 5 6 7 0 10 20 30 40 50 Wear Rate (1x10 -13 m 3 /m) Number of Cycle Applied Load : 1N Applied Load : 2N Applied Load : 3N Applied Load : 4N Fig. 4.
Variation of wear rate of the ARB processed 5083 Al alloy as a function of number of ARB cycle.

Experimental points are shown for both the unprocessed (coarse-grained) and for the ECAPed materials.
The theoretical rates using dECAP will be marked by simple number (e.g. 1) while a numbering with asterisk (e.g. 1*) will be used for the rates corresponding to dCREEP in Fig. 1.
Further, for n ³ 4 creep is known to occur by diffusion-controlled movement of dislocations within grains and/or along grain boundaries (grain boundary sliding).
Supposing that grain boundary sliding is controlled by grain boundary diffusion, which is assumed to be about 0.7 times that for lattice self-diffusion, the presented results give support to the assumption that grain boundary sliding may be increasingly important in the ECAP aluminium and copper at low applied stresses (see Fig.2a).
Diffusion creep is not important because the ultrafine-grained microstructures are unstable at creep temperature and the grains grow during creep sufficiently to preclude any significant contribution from diffusion creep.

Evolution of the ferrite mean grain size as a function of the transformed fraction The number density of ferrite grains was determined for all the steels and treatments.
However, in order to compare the different results and taking into account the fact that ferrite grain size changes during transformation, the number of grains per unit volume, Nv, had to be determined.
Taking into account the fact that the austenite grain size is similar for all the steels, an increase in the number grain density means a major refinement in the final ferrite microstructure, as is observed in Figure 1.
In the case of V-1 steel, it was observed that the number of grains is higher than in the C-Mn steel at all transformation stages, though the difference becomes very important at the later stages when a significant increase in the number of grains, particularly after treatment B, occurs.
In all cases intragranular nucleation takes place at relatively late stages during transformation and contributes to the refinement of the final microstructure by increasing the number of grains.