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Reference [4] gave a comprehensive review of the fractal theory, it evaluated the grain characteristics of cementing materials and the surface characteristics of aggregate in concrete materials, and the fractal characteristics of concrete pores and the fractal effect of fracture toughness and fracture energy, and the application of the fractal theory in acoustic emission in concrete materials, and gave the application prospect of the fractal theory in concrete study.
Acoustic Emission Process Parameters and Their Fractal Characteristics (1) Introduction of box dimension Assuming that is any nonempty bounded subset in an space, and denotes the minimum number of -dimension cubes (boxes) with edge length of , needed to cover , for any .
In actual calculation, the number of the boxes with different values, covering , may be calculated using some -dimension cubes (boxes) with edge length of , according to the needs, and then points (,) are plotted in a log-log coordinate system with as abscissa and as ordinate; finally, the box dimension of the set can be estimated from the slope of these distributed points[9-10]

For instance, it has been shown in a number of articles [1-4] how the presence of casting defects either as micro, or macro porosity, affects the fatigue life of steel castings.
During bending a number of cracks opens up at each side of the hole at the top side of the bend, because of stresses due to the notches formed by the hole.
Most likely the observed differences in behavior between the two material variants, i.e., the hot forged and the cast material, are due to differences in microstructure, as hot forging must provide smaller grain size in the material.

Leaching column at the bottom of the shop was a 1 cm thick layer of sand, with 1 cm thick sand coated on the fine sand, added the coal grain size is less than 1 mm 100 g (about 5 cm thickness), then added1 cm thick coarse sand on coal gangue, all vessels using in test acid soaking, deionized water rinse.
A number of research results showed that [7], coal or arsenic is closely related to the three states of sulfur in coal gangue.
The lower the pH, the more increasing in the number of H+, it made the exchangeable arsenic increase in coal gangue, which benefited the leaching of arsenic in coal gangue.

At the architectural acoustics website of a well-known university, a considerable number of property owners ask questions about residential sound insulation everyday; moreover, disputes and litigation relating to residential sound insulation have shown a growing trend.
For example, multiple layers of different close-grained boards could be separated by using porous materials (e.g. glass wool, rock wool and foam plastic) to create a sandwich structure. .
This shows that it's possible to improve the sound insulation capacity of lightweight partition by increasing the number of layers of thistle board, filling the cavity with sound-absorbing materials or optimizing the construction & installation techniques. 3.2 Lightweight Strip Board Partition Fig. 4 Sound insulation - frequency characteristic curve of partition made from double-layer fiber reinforced strip board Featuring large width, light weight and convenient construction etc., lightweight strip board is suitable for internal partition in high-rise residential buildings. .

That is because heating above the BTT at the finishing steps of heat- and thermomechanical- treatments leads to strong grain growth, followed by mechanical properties degradation.
Presently BTT is determined mainly by means of a structural analysis of specimens quenched from the BTT interval [1-3], but it has a number of disadvantages: labour intensity; low efficiency; as well as subjectivity in some cases.
To limit the number of factors affecting the DSC results, all the chosen alloys were characterized by a value of aluminum equivalent from 8.5 to 10.5.

The patterns of XRD match well with the standard card number of Cu2FeSnS4 stannite structure (ICDD No:44-1476).
(4) Where I°(hkl) and I(hkl) are the standard card's intensity experimental intensity, respectively, of the X-ray diffraction pattern, Nr is the number of peaks identified, and the Miller indices are hkl.
The images from the FESEM technique showed various grain sizes and shapes.

To maintain a constant power, the height of the peaks must increase as the number of “on” pulses is decreased.
That is because the local micro area’s instantaneous large voltage caused by the reduction in the number of “on” pulses generates the high instantaneous energy that is concentrated at the particle boundary regions and assists in the welding of the particles under mechanical pressure [19].
Huge effect of weak dc electricalfields on grain growth in zirconia.

Here, the applied centrifugal force was G number of 80, where the G number is the centrifugal force in units of gravity.
Term)×Wgb (m3/s) 1.71×10-4 - Activation energy (J/mol) 1.42×105 - Atomic volume (m3) 1.2248×10-29 - Grain size (m) 0.3×10-6 - Diameter of a particle is 150×10-6m, Dint×Wint is assumed to be the same value as Dgb×Wgb for Al.

The definitions of df include a drag function (CD) that is based on the relative Reynolds number (Res).
The total grid number used was 6862.
Model predicts flow behavior well with cluster formation in annulus region and periodic flow of grain through each zone of apparatus.

The average grain size of the material in rolling direction was measured to be 20 µm.
For example, the damage parameter PSWT, proposed by Smith et al. [10], is usually used, where Ni refers to the number of cycles to crack initiation lifetime: ( ) ( ) ( ) cb i ff b i f ama SWT NE N E P + ⋅⋅'⋅'+⋅'=⋅⋅+= 2 2 2 2 εσ σεσσ (3) In notch sections of components the local stress distribution )z,y,x(σ has to be taken into account.
Consequently, the scatter of strength σ at a constant number of cycles to crack initiation Ni is given by the well known Weibull distribution: ( ) �� � 
 �� � � 
 �� � � �� � � ⋅−−== κ σ σ σ V max imax SI SI exp.constN,P 0 1 (4) where maxσ represents the maximum local stress.