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A number of examples exist that indicate the potential for increasing the toughness of brittle matrices by dispersing different reinforcements.
A propagating crack will always choose the path of the least resistance, so deflection is achieved by introducing planes of weakness (e.g. grain boundaries) or by introducing areas of higher resistance (e.g. second phase of higher toughness), e.g. [8].
Whiskers or other second phases as well as matrix grains have been shown to bridge the crack for some distance behind the crack tip [4,9,10].
Key test technique necessary for fracture behaviour evaluation Fracture toughness characteristics (KIC) of brittle materials are commonly evaluated from the indentation method by a number of research laboratories [14,15].
Brittle matrix reinforced by metallic or ceramic particles A number of examples exist that indicate the potential for increasing the toughness of brittle matrices by dispersing a particulate ductile phase [7,8].

Therefore, there is a reason to suppose that seismic forces (even minor ones) accelerate failure occurrence in a number of pipeline sections and serve as “the last straw” that causes accidents.
To define the limit longitudinal movement of the pipeline in soil, a relationship (2) obtained based on experimental findings was used [2]: appears after the equation but before the equation number, e.g.
For comparison based on ASCE Guideline the value of soil limiting resistance to pipe axial deflection was defined based on the following relationship (for sandy soil backfill): appears after the equation but before the equation number, e.g.
In that case the passage of seismic wave is accompanied by propagation share wave where soil grains’ vibration direction is perpendicular to wavefront movement direction.

The excess paste theory was used to determine the thickness of the paste coating each aggregate with a given diameter of constituting granular skeleton, then generalized for the determination of the quantity of total paste allowing the flow of the concrete by decreasing frictions between the grains of its granular skeleton.
For a chosen granular skeleton having weight ratio gravel/sand (G/S) defined, a sufficient optimal self-compacting paste is prepared, to which will be added the granular mixture; a part of this paste is going to cover the aggregates and the rest fits between these grains and fills the space, thus causing separation of the skeleton, which would induce a difficulty of flow of the concrete thus formed.
Excess paste (Vpe) Compact paste (Vpc) Aggregates (VG) Compaction Fig. 3: Explanatory plan of the excess paste theory Homothety factor for every ratio (G/S) can be determined by the following relation : (2) (Ni) is aggregates number with diameter (Di) of the class (i), VG > 80 is aggregates volume with diameters greater than 80 µm (without fillers).
Conclusion Excess paste theory was used to determine cement paste thickness coating every aggregate of diameter given constituting the granular skeleton, and then generalized for total paste quantity determination, allowing the flow of concrete by decreasing frictions between grains of its granular skeleton.

The tungsten carbide ceramic particles of the medium grain size according to FSSS = 50 µm were introduced using the rotor conveyer to improve the properties of the surface layer.
The tungsten carbide powder of the medium grain size according to FSSS = 50 µm (Fig. 1) was used to obtain the highly resistant gradient layers and various laser power sequences were employed: (1) Specimen was remelted with the 2.3 kW laser and next alloyed twice with the WC particles with the laser beam power values of 2.0 and 1.6 kW respectively (2) Specimen was remelted with the 2.0 kW laser and next alloyed twice with the WC particles with the laser beam power values of 1.6 and 1.2 kW respectively (3) Specimen was alloyed twice with the WC particles with the laser beam power of 1.2 and 1.6 kW respectively, and next remelted with the 2.0 kW laser (4) Specimen was alloyed twice with the WC particles with the laser beam power of 1.6 and 1.2 kW respectively, and next remelted with the 2.3 kW laser a) b) Fig. 1. a) Topography
At low laser beam power values some of the tungsten carbide grains remain at the surface, causing its high roughness; whereas, at the higher laser beam power values the steel surface is formed in a very specific shape, resulting from the fast crystallization in the heat transfer direction and from the protective gas blow-in interaction.
It was revealed also that the increase of laser power results in dissolving most of the introduced WC particles and causes increase of the number of cracks in the surface layer.

The analysis methods confirmed that introduction of chrysotile nanofibers suspension into the composition of a cement binder makes it possible to significantly vary the structure and morphology of new formations in fine-grained concrete.
First, in the early stages of the cement systems hydration, they act as centers for the formation of calcium silicate hydrates C-S-H, which leads to the development of a large number of intergrowth contacts in the cement system, resulting in the creation of a more homogenious and less stressed structure.
Investigated were standard beam specimens with dimensions of 40x40x160 mm with a concentration of chrysotile fibers from 0.5 to 2% of the cement mass in the composition of fine-grained cement concrete with a cement to fine aggregate ratio of 1:3.
The results of physical and chemical analysis of the modified fine-grained concrete samples show that introduction of the chrysotile nanofibers suspension into the composition of a cement binder changes the structure and composition of the cement matrix with the formation of calcium silicate hydrates of a lower basicity, which leads to an increase in the strength of the cement concrete.

The results obtained from SEM/EDX analysis for the reduced samples HR15 (15% Polystyrene (PS) + 85% coal (C)), HR25 (25% PS + 75% C) and HR35 (35% PS + 65% C) showed that most of the Titanium oxycarbonitrides were found in the circular shape with increase grain coarsening.
The ICSD numbers for the ilmenite, magnetite and hematite detected were 98-004-8824, 98-001- 7267 and 98-003-5777, respectively.
During fast reduction of iron oxides from ilmenite sand in hydrogen atmosphere, fine metallic iron grains were formed.
Reduction of ilmenite in inert gases resulted in formation of coarse grains of metallic iron with a denser particle structure in comparison with reduction in hydrogen [12].

Several studies with regard to grinding heat have been carried out, focused on micro phenomena of abrasive grains or macro phenomena of thermal deformation in grinding machines.
Some researchers revealed that micro phenomena of abrasive grains such as mechanisms of grinding heat, and theoretical and experiment analyses for distribution of temperature at grinding point [1,2].
In addition, the heat transfer coefficient of coolant is indefinable because digit number changes from ca. 10 3 up to 10 4.

The stretching-vibration mode (A2u) of Sn-O and deformation-vibration mode (Eu) of O-Sn-O were found to be broadened and shifted towards the higher wave numbers in case of cobalt doped samples.
The average grain size of the nanoparticles were calculated from XRD peaks by using Scherrer formula D = 0.9 λ/(βCosθ), where β is the full width at half maximum of the high intensity peak expressed in radian.
The A2u and Eu modes were found to be shifted toward the higher wave numbers with increase in cobalt contents, which may due to the change in O-Sn-O environment with the presence of cobalt.
Since, lighter molecules give their vibrational modes at higher wave numbers therefore, the appearance of the Eu and A2u modes at higher wave numbers could be due to the incorporation of cobalt into the tin oxide lattice via formation of cobalt substituted SnO2.

Inputting the ultrasonic signal's time parameter and frequency parameter as characteristic number, through training and learning,we can indentify the failure's style.
When the number of input is unit-n, the hiding is unit-q and the outputting is unit-m, the BP Neutral Network can be expressed as BP(n, q, m).We can fulfill the non-linear mapping from the inputting unit-n to the outputting unit-m by the BP Neutral Network.
It is relevant between the number of hiding layers and the question’s request, the number of input/output.
We choose four inputs(X1,X2,X3,X4): the X1 means the parameter of horizontal speed, the X2 means the parameter of vertical speed, the X3 means the parameter of horizontal frequency, the X4 means the parameter of vertical frequency; three output layers(Y1,Y2,Y3):the output of (1,0,0) means the concrete is close-grained , the output of (0,1,0) means there is a delimitation in it, the output of (0,0,1) mean there is a inanition in concrete.

ROP evolved from return-to-lib(c), which is a course-grained code-reuse attack.
ROP is a fine-grained code-reuse attack, with which attackers can perform arbitrary computation [1], as shown by Shacham in his paper.
Chen et al. [7] proposed one feature of ROP: the number of consecutive sequences that end with ret is greater than 3 and each sequence contains no more than 5 instructions, based on which a detection tool DROP was implemented.
Fine-grained randomization is more powerful and more difficult to implement.
Assume that the number of functions in an executable is n, an ROP attack can succeed with one trial with ASLR and it will succeed with n!