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From the mechanism of fatigue crack growth of N80, defects and cracks resulting from fatigue are the numbers of kind of fluctuations.
Interim of fracture, crack propagation was striped, and occurred fracture layer, cracks propagation is very fast, about 1000 number of cycles per mm, crack growth stripes of about 1 (Fig.2a).
Due to stand material transverse force, material and fracture of the crystal is not parallel to the direction to material intergranular fracture occurs along the direction of the grain boundaries have small cracks.
From the mechanism of fatigue crack growth of N80, defects and cracks resulting from fatigue are the numbers of kind of fluctuations.
Low-frequency noise is very sensitive to the fluctuations of the number of defects, cracks and microstructure, which can serve as a viable tool to study the defects and the characterization of defects.

The Hardness Number as a measure of the degree of plastic deformation Hardness tests have been conducted for a long time to characterize materials, mostly because of their characteristics (simple, non-destructive, low-cost), as well as for their capacity to assess low-volume mechanical characteristics, [1].
As known, [2], the hardness Number represents a measure of degree of plastic deformation suffered by some materials.
For normal 1C45 (1.053) steel, the graph of Fig. 2a allows the conclusion that high hardness values are registered in the zone where fatigue crack was initiated, which required a significant number of loading cycles, about 120.000.
Vickers hardness increases in the area of the sudden fracture of the specimen (the final zone, with bigger and more brilliant grains), the values registered in this zone occurring within a certain level.
The hardness values are higher in the zone where the fatigue crack is initiated, for which a relatively high number of fatigue cycles are necessary.

When coupled with large and variable grain sizes, the HCP structure has in the past lead to less than optimum mechanical properties.
While the weight savings with magnesium has the potential to be enormous, in comparison with aluminum the tensile strength of magnesium is approximately 25% less, fatigue behavior (number of cycles to failure) is 35% less, hardness 30%, modulus, 40%, and thermal expansion 15% less.
(9) Where cσ∆ and p cε∆ denote local stress and strain of a randomly distributed single crystal while σ∆ and p ε∆ are the overall stress and strain that are considered as the average of the local stresses and strains over all randomly distributed single crystal grains. 1 1 i � p p c i� ε ε ' = ∆ = ∆ '∑
Stress-strain hysteretic loop data were captured following linear increasing cycle number basis at the first 5 cycles.
As observed in Figure 10, the cyclic mean stress mσ decreases with increasing cyclic number N for AM60 with strain amplitude aε =0.3% and R ratio R=0.7 obviously.

In cyclic conditions, the weight gain vs. cumulative cycle number curves showed approximately parabolic behavior at 850 and 950°C.
Cycle number 0 25 50 75 100 125 150 Mass variation (mg/cm²) -2 -1 0 1 2 3 Fe-17Cr-0.4Ti Fe-17Cr Fe-17Cr-0.2Ti Fig. 4.
Number of cycles Fe-17Cr Fe-17Cr-0.2Ti Fe-17Cr-0.4Ti 150 0.7 % 0.23 % 7.3 % 300 0.02 % 0.54 % 3.2 % Oxide characterization.
It was also observed on the cross sections that both reference and low-Ti grades exhibited marked interface undulation, whereas the high Ti grade exhibited a flat interface, except at the locations of grain boundary emergence.
Scale adhesion seemed to be directly linked to chromia scale keying into the steel substrate at locations of grain boundary emergence.

a) d) g) b) e) h) c) f) i) Fig. 2 Morphologies of dendrite growth with and without heat flux Compared with the extraction boundary condition, under the Zero-Neumann boundary condition the under-cooling was smaller, while the growth rate was slower, and the number of secondary dendrite arms was less.
The disturbance at the interface was difficult to be amplified and the number and size of secondary branches was the least, so the solute can be diffused fully.
Fig. 7 The Peclet number of dendrite growth process versus time As can be seen in Fig. 7, with the increase of temperature the simulation result became gradually consistent with Ivantsov function.
Grain growth competition during thin-sample directional solidification of dendrite microstructures: A phase-field study [J].
Growth competition of columnar dendrite grains: A phase-field study [J].

Hierarchical clustering is known that can obtain multi-level clustering structure of different particle size, by which, we can get small number of radar signals drown in many radar signals.
By using data field to determine the cluster center and cluster number, the appearance of false alarm and missed alarm caused by lack of lack of prior information of the cluster centers and cluster number can be avoided to a great extent.
Then deinterleaver the signal sample with traditional cluster algorithm, in which we assume that the category number is 4.
Sorting Result of Improved Algorithm Based on Data Field Serial number 1 2 3 4 Actual number of pulses 277 332 262 237 Number of pulses sorted 299 303 269 237 Number of pulses sorted correctly 277 303 262 237 Number of pulses missed 0 29 0 0 Number of pulses sorted wrongly 22 0 7 0 correctly sorted rate 97.38% CONCLUSIONS It's difficult to sort signals of new radar systems, of which number differs greatly.
Experimental results show that the method can avoid the influence caused by that number of pulses received differs greatly.

Qiu Daoyin uses BP neural network technology to distinguish pests in stored grains with a recognition rate of 100% [7].
In the design of BP neural network, the number of hidden nodes has significant influence on the network performance.
Furthermore, there has not yet been definite theoretical direction for choosing hidden nodes number.
(3) Where: is respectively input nodes number.
is respectively output nodes number.

The influence of methods for converting torsion data (torque, number of turns and speed rotation) into equivalent variables (true stress, true strain and true strain rate) on the Garofalo equation parameters is studied.
Usually, the von Mises and Tresca equations are considered [10]: τσ 3=vM τσ 2=Tr (5, 6) On the other hand, the true strain and strain rate are obtained from the number of turns and the speed rotation.
Results and discussion Fig. 1 shows a set of torque-number of turns curves at 10 s-1 and different temperatures.
Torque-number of turns curves at 10 s-1 and various temperatures.
The decrease with strain observed in our work is related to the effect of dynamic recrystallization and probably to grain size reduction with strain.

Because most studies on the strength in terms of atomic mechanics have focused on the factor (1) (materials), analysis has mainly been conducted on simple crystal consisting of perfect lattices (e.g. fcc and bcc) under simple loading conditions (e.g. tension), though some have explored the properties of bulk materials with defects (e.g. vacancy and grain boundary).
On the other hand, investigation of the strength of bulk materials and macroscopic structures has long history (e.g. [4]), and the number of related articles published runs into astronomical numbers.
In the same framework, we could discuss the ideal strength of grain boundaries and interfaces with periodicity, even though they are not nano-components.

To resolve main difficulties encountered in demulsifier research today, such as demulsification of viscous crude oil emulsion, demulsification of chemical flooding emulsion, some research value routes, such as increasing aromaticity, molecular weight and branch degree of demulsifier molecule, and leading double-function groups meeting W/O type and O/W type emulsion and groups with alkyl carbon number matching equivalent alkyl carbon number of the crude oil into demulsifier molecule, were suggested according to demulsification mechanisms and their emulsion characteristics, and action mechanisms of the above-mentioned research routes were elaborated at the same time.
The solid particles in the interface films of heavy oil emulsion, such as asphalt, paraffin grain, clay particles, metal salt particles and mechanical impurities, are of high content due to the high content of heavy oil asphaltene particles and the strong carrying capability of heavy oil on solid material, which increase the stability of emulsion.
The emulsion state of produced liquid have a qualitative change: oil-water emulsion changes from W/O type in early stage of oilfield to O/W type, and complex multiple emulsion that O/W type and W/O type coexist is also in the liquid, and produced liquid contains a large number of fine O/W emulsion that is difficult to coalesce and separate.