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Slow crack growth of the surface defects from oxidation at grain boundaries in the fibers has been shown to be the driving mechanism of delayed failure [6].
It depends on the size of the cluster defined by the number of touching adjacent fibers.
First of all, the fibers which are considered successively are selected randomly through 3 parameters (fiber section Si, elementary force f and strength f ) which were choosen using random numbers X, Y and U: X = PG (Si) (6) Y = PN (f) (7) U = PW (f) (8) Then, the overload that is experienced by the next fiber is also selected using the same method: Z = PN (f + f) (9) The microstructure is characterized by the distribution of cluster sizes (figure 4).
The force F operating on the longitudinal tows was derived by assuming that the force on composite was shared equally by all the longitudinal tows: F =  compF (10)  was taken to be the number of longitudinal tows within the specimen (150). 50 computations per force were carried out.
It was based on the number of tows present in the composite specimens.

Moreover he demonstrated that thick oxide scales crack more quickly than thin ones (the number and the length of the defects being higher in the thick oxide scales).
The cracks density per length units is determined with the number of interceptions between cracks and a virtual circle, such like for classical grain size determination.
Then this number is divided by the circle diameter.
A statistical study of the inter-cracks spaces was then carried out; this study was done using images taken at 500× magnification and for a constant total number of inter-cracks spaces (10).

SupowerTM PCD cutters with 2-30 μm tool grain size were used in the machining tests.
Test number Cutting speed v [m/min] Feed rate fz [mm/tooth] Radial depth of cut aw [mm] No.1 250 0.15 3 No.2 250 0.1 2 No.3 250 0.05 1 No.4 150 0.15 2 No.5 150 0.1 1 No.6 150 0.05 3 No.7 50 0.15 1 No.8 50 0.1 3 No.9 50 0.05 2 The goal of this study is to optimize the milling parameters to get lower cutting force and cutting temperature so as to reduce the tool wear rate.
That means that the objective function, S/N ratio, is calculated based on the-smaller-the-better characteristic, which can be calculated as: (2) where yi is the observed data and n is the number of observations.
Table 4 Experimental results for cutting force and S/N ratio Test number No.1 No.2 No.3 No.4 No.5 No.6 No.7 No.8 No.9 Cutting force F [N] 888 646 369 836 577 740 764 911 859 S/N ratio [dB] 58.96 56.21 51.35 58.44 55.23 57.38 57.67 59.19 58.68 Table 5 S/N response table for cutting force Symbol Cutting parameters Mean S/N ratio [dB] Level 1 Level 2 Level 3 Max-Min A Cutting speed 55.51 57.02 58.51 3.0 B Feed rate 58.36 56.87 55.81 2.55 C Radial depth of cut 58.51 57.77 54.75 3.76 The non-linear multiple regression analysis method has been deployed to analyze the cutting forces in the form of empirical equation.
Table 6 Experimental results for cutting temperature and S/N ratio Test number No.1 No.2 No.3 No.4 No.5 No.6 No.7 No.8 No.9 Cutting temperature θ[℃] 699 520 321 408 385 473 341 506 347 S/N ratio [dB] 56.89 54.32 50.14 52.22 51.73 53.50 50.66 54.09 50.80 Table 7 S/N response table for cutting temperature Symbol Cutting parameters Mean S/N ratio [dB] Level 1 Level 2 Level 3 Max-Min A Cutting speed 53.79 52.48 51.85 1.94 B Feed rate 53.26 53.38 51.48 1.90 C Radial depth of cut 54.82 52.45 50.84 3.98 Fig. 5 S/N response graph for cutting Fig. 6 Cutting temperature for different temperature workpiece materials and tool wear (v=100 m/min, fz=0.08 mm/tooth, aw=1 mm, ap=3 mm) The non-linear multiple regression analysis method has been deployed to analyze the cutting temperature in the form of empirical equation.

From the FTIR spectra of HA-Zn (Fig.1.) it can be observed the presence of a small number of the absorption bands.
The most intense band in the apatites FTIR spectra is the band attributed to the stretching vibrations of P-O bonds in phosphate group (PO) in the area of 1000-1100 cm-1 wave number.
This band is accompanied by a secondary band due to the bending vibrations in the area of 500-600 cm-1 wave number.
SEM micrographs of the HA-Zn sample, at 100 °C, 300°C, 500°C 800°C, and 1000°C (x15 000) Brunauer, Emmett, Teller analysis (BET) The specific surface area of the powder is closely related to the size of the powder grains.
Preliminary results to determination of the effective atomic number

The Research of LED Lights Model Based on Road Lighting in Mesopic Vision Fangzhou Zhu *1, a, Weihai Yuan1,b , Huamei Xu 2,c and Yuefeng Yuan1,d 1Anhui Economic Management Cadres Institute, China 2 Anhui Vocational College of Grain Engineering, China afangzhou_zhu@126.com, byuanweihai@sina.com, cxuhuameimei@126.com, dyf.yuan@163.com Keywords: LED, the white and green LED, human visual characteristics, Mesopic vision.
The road lighting high pressure sodium and metal halide lamps, and many scholars in the middle of the visual state of high pressure sodium, metal halide light efficiency, a number of outputs [5].
The feelings of the human eye on the overall intensity of the LED light source can be sensitive visual intensity of each color cell integrated into a synthesis of the impulse to pass into the brain, its LED light source with the optical model shown in Fig.4: Fig. 4 LED light distribution model Fig.4 can be seen R, G and B present three primary colors of red, green and blue intensity of stimulation, M said that the human eye cone cell sensitivity coefficient, T1, T2, T3, pyramidal cells of the human eye on the three primary colors corresponding sensitivity, log used to simulate the human visual pyramidal cells in the visual response curve to match the sensitivity to take on the number of log operations, N said that the human eye rod cell sensitivity coefficient, C1,, C2, C3, respectively, the contrast in black and white, red and green contrast, yellow-blue contrast, , , are filtering function, Y is the brightness, B1and B2 are Chroma.
When the white and green LED is used for road lighting, it ensures the safety of a large number in energy saving.
Acknowledgements The young talents Fund project of Anhui province in 2010( Number: 2010SQRL206).

Studies [3,4] have demonstrated the importance of this process in low alloy steels for a thickness of about 6 to 12 mm, for the grain refinement in Heat Affected Zone (HAZ), an enhancement of the metallurgical weldability with regard to arc welding processes, and producing no welding fumes particularly containing hexavalent chromium.
DebRoy, Review: friction stir welding tools, Science and Technology of Welding and Joining, Volume 16, Number 4 pp. 325-342, February 2011 [2] K.J.
Grimmett, R.W Warke, Friction Stir Welding Studies on Mild Steel, Welding Journal, Volume 82, Number 1, pp1s-9s, January 2003 [4] T.
Steel, Friction Stir Process Now Welds Steel Pipe, Welding Journal, Volume 88, Number 5, pp. 44-48, May 2009 [6] C.
Hattel, Numerical optimisation of friction stir welding: review of future challenges, Science and Technology of Welding and Joining, Volume 16, Number 4, p. 318, 2011 [7] Bureau Veritas NR 216 DT R06 E, Rules on Materials and Welding for the Classification of Marine Units, edited by Bureau Veritas, Feb. 2013 [8] EN 10025-6 standard, Hot rolled products of structural steels - Part 5: Technical delivery conditions for structural steels with improved atmospheric corrosion resistance, edited by AFNOR, 2004 [9] ISO 15614-1 standard, Specification and qualification of welding procedures for metallic materials - Welding procedure test - Part 1: Arc and gas welding of steels and arc welding of nickel and nickel alloys, edited by AFNOR, 2004

TEM Morphology of (a) 1M-FLGNSs and (b) 2M-FLGNSs The SEM micrograph in figure 6 (a) shows a less porous and planar mosaic layer stacking arrangement of graphite grains for the graphite sheet.
Figure 7 (a) depicts TEM images wherein 1M FLGNSs display peeling of bigger GNSs domain with a large number of layers and low transparency due to the overlapping of many layers.
Figure 7 (b) displays 2M FLGNSs herein the thinness and better transparency in the GNSs is observed due to less number of graphene layers.
Scanning probe microscopy analysis Scanning probe microscopy is a superior tool for a better comprehension of lateral dimensions, number of layers and functionalization.
AFM and STM provide idea about the thickness and number of layers.

This disaster will bring huge economic loss and even kill large number of people and destroy the whole mine.
And the most serious country is China, in this country, all parameters of coal-gas outburst, such as total number and average strength, are the most serious, and the total number of China is approximately one-third of the world [5-7].
Due to high rigidity, close-grained, and low permeability, inner gas is difficult to emit out before the crack of hard coal, and this result to high gas pressure.
But the break of hard coal generates large number of paths and let inner high pressure run out.

DUV ozone treatment, where two wavelengths of 185 nm and 254 nm are employed, is an effective technique that could concurrently decrease the amount of defect sites related to oxygen vacancies and increase the number of metal oxide (M–O) bonds [16].
While the surface of STO thin films that have been subjected to the UV-photoactivation or conventional annealing at 300oC have the shape of hills and valleys, with bigger grains as illustrated in Fig.1 (e) and (f), respectively.
However, DUV photoactivation reduced the numbers of defect sites down to 25%.
Oluwabi et.al. [16] reported that DUV activation enhances the quality of their ZrO films by increasing the number of M–O bonds and decreasing the number of oxygen vacancies.

The diffraction peaks found at 37.34˚, 43.38˚and 63.02˚ (2θ) can be indexed according to the JCPDS number (01-073-1519) of cubic NiO structures.
In addition, the agglomeration of silica particles increases due to the reduction in pore size and the decreasing number of pores.
This is well supported by the morphology of sintered forms as shown in Figure 4 where a higher number of open pores were observed at lower temperature.
As the sintering temperature increases, the number of open pores decreases thereby leading to a decrease in porosity.
Jung, Effect Of Sintering Temperature On Nanostructure And Grain Boundary Diffusion Of Plasma Sprayable Calcined Nio-8ysz Cermet Particles, Dig.