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Machining Science & Technology, 1997, 1(1):113-152. ].There are also demands to process a large number of holes for connection and assembly, but many problems such as delamination, burr, chipping, poor machining quality and tool wear in drilling of C/C composites exist due to inhomogeneous, anisotropic, wear resistance and varying thermal properties of the composites [[] Hojo M, Yatomi M, Tsuda H, et al.
Rotary ultrasonic machining (RUM), as a non-traditional machining method, has a large number of advantages in the aspect of hard brittle materials processing compared with conventional machining [[] Pei ZJ, Khanna N, Ferreira PM (1995) Rotary ultrasonic machining of structural ceramics-a review[C].
The trajectory of a single diamond grain can be described by the set of equations[17]: X=rcosωt Y=rsinωt Z=Asin2πft+vft (1) Where r is the radius of the tool, ω is the angular velocity of the spindle, A is the amplitude, vf is the feed rate, f is the vibration frequency and t is the time.
Figure 3 Experimental set-up Figure 4 Tool parameters Table 1 Tool parameters Parameter Value Parameter Value Outer diameter 12 mm Inner diameter 9.8 mm Grit size 80/100 Grain concentration 100 Bond type Brazing-bond Grits distribution 12 columns 3.2 Experimental conditions The C/C composites workpiece (Chaoma technology corp., Xi’an, China) was 2.5D acupunctured structure which consisted of 35% carbon fibers and 64% carbon matrix made up of resin carbon and pyrolytic carbon.

It analyzed the relationship between cement slurry viscosity, grouting pressure, the effective grain size, permeability coefficient and the grouting concretion stones strength, in order to provide a reference for practice engineering.
The permeability of the media is mainly controlled by the pore characteristics such as the shape and size of pore, the pore connectivity and the number of pore.
Numbers of data are very limited relative to the complex experimental factors and their relationship.
Where xi is equal to Xi, and xi belongs Rd which i is the number of training ranged from1 to l.
(7) (8) Where l is the number of training set sample, yi is the real value and is the prediction value for No. i. i is real number ranged from 1 to l.

Introduction Small precipitates can substantially increase the strength of a material, since their presence hinders dislocations and grain boundaries from freely migrating through the microstructure.
Some of the parameters of major importance for precipitation hardening are the size, number and distribution of precipitates as well as their long-term stability.
In the last two decades, computational thermodynamics based on comprehensive databases for a number of different materials has been employed with great success to assist the development of optimum production routes [1].
The model In the new model, a unit cube of matter is considered, which contains an arbitrary number of precipitates of different type, chemical composition and size.
If a positive J is calculated, a number of J∆t of new precipitates is created and added to a list of existing precipitates.

Moving the vertexes of the projected triangles vertically into a grid a limited number of possible modules arises.
This number depends on the defined gradient and the axial dimension of the grid.
It results out of the squared number of included grid elements.
Putting the corner points in a grid one gets a finite number of different triangles.
If it is not allowed to mirror the components the number of necessary tools doubles (see Figure 4).

With the increase of the number of atoms in the crystal cell, the equilibrium lattice parameters of each crystal structure also change, showing different change trend.
The number of candidate materials can be calculated as C (32,6) =906192, which is 106.
Due to the number of 106 grade candidate samples generated in high-throughput doping calculation of copper alloys, a lot of computing resources and time are needed.
As shown in the figure below, the initial structure count is 30, the maximum count is 10 each time, and the loop cross validation number is 0.02.
Gavriljuk, On a mechanism for enhanced hydrogen flux along grain boundaries in metals, Acta Mater. 194 (2020) 516–521.

In a number of works, the presence of the mesoscopic level of deformation was theoretically grounded and experimentally proved, which allows considering the materials subjected to deformation as the self-organized systems [1-5].
In a number of works, the notions of self-organized relief formations, deformation of surface layers and internal boundaries between polycrystals are used, which play an important role in the nucleation of deformation defects.
, , , (4) where is the value of statistics in the discrete th moment of time; is the number of countdowns for the registered realization of the signal; is the value of the discretized realization of the signal at the th moment of time.
Within the context of the proposed mathematical model of the surface covered with deformation relief, we interpret a number of its main elements, such as the cycle, phase and rhythm of the relief formation process.
Mishnaevsky Jr, Non-equilibrium grain boundaries in titanium nanostructured by severe plastic deformation: Computational study of sources of material strengthening, Comput.

Schematic diagram of sensors placement of third layer block is shown in Fig.1(b), the number on line is the size from sensors to the heating tube, which is expressed by “d”, there are four sensors respectively at d=20mm, 45mm, 70mm, 95mm in the third layer block.
Nature Na-bentonite samples from inner Mongolia Gaomiaozi in China are milled and screened, grain size 200 mesh, drying temperature(105±3)˚C until constant weight.
Gradually, the temperature value set on the control is increased with the experiment operation until the temperature of the number 8 sensor achieve to the required value.
At the first stage, the temperature of the number 8 sensor in the third layer bentonite block reach to about 55˚C, the distance of the number 8 sensor is 20mm to the heating source; When the temperature come to equilibrium after a very long time, heating gradually again, finally, the temperature of the number 8 sensor increase to about 82˚C.
Change trend of four curves can be seen in Fig.2, the temperature of the blocks increase quickly at the beginning, after about 20 hours, the temperature of the number 8 sensor with d=20mm reach the maximum 55˚C or so, from then on the temperature slightly decrease, the time is about 40 hours, it change to be steady; at the second stage, the temperature of number 8 sensor rise to about 82˚C, coming to balance.

Soybean oil was provided by Dantu grain and oil chemical plant, China. -10PD was obtained from China Petroleum & Chemical Corporation.
Table 1 Main composition (wt.%) of SME a SME Content SME Content C14:0 0.19 C16:1 0.26 C16:0 11.09 C18:1 28.56 C18:0 5.50 C20:1 0.41 C20:0 0.60 C22:1 0.11 C22:0 0.69 C18:2 42.95 C24:0 0.22 C18:3 7.74 aCm:n: shorthand of fatty acid methyl ester. m: the number of carbon atom in fatty acid group. n: the number of double bond.
To organic compounds with similar composition and structure, substance volatility got poor with increasing the molecule mass (the number of carbon) and molecule 3D-structure.
It was chiefly because -10PD was mainly composed of alkane of 8-26 C atoms, and SME was mainly composed of FAME of 14–24 even-numbered C atoms.
Xie: Effect of Fuel Volatility and Cetane number on Emission of Diesel Engine, Jilin University, Jilin (2006) (In Chinese) [6] D.

The bright primitive length is defined as LBi(j), It represents the number of primitive sequence of "1".
The dark primitive length is defined as LDi(j),It represents the number of primitive sequence of "0" .
(2)Statistics numbers of black and white transitions per line , such as (8) .Taking into account the characters, background interference and other factors, plate region is generally composed of seven characters and borders , the number of transitions of each line within the region of 18 times at least, the transition threshold is set to 24
Positioned around the boundary According to the real license plate character area than most pseudo- plate region in the vertical projection of the direction of the peak - valley distribution with intermittent and intensive ,proposed use of the vertical projection method to remove the pseudo -plate region ,Then, the license plate area has a number of characteristics of transition than the other with the size of the region to define a rectangular sliding window ,sliding from left to right and statistics times of jump within the window .Lastly, to find window position that the number of transitions is most as the boundary position of rough location , which shown in Figure 3 .
The first license plate image preprocessing, including gray scale stretching to balance the light, the median filter to remove grain noise , enhance the level of differential edge features , etc.; line scanning method according to the license plate texture features of the region and sliding template the method for coarse positioning ; projection characteristics of the license plate region using the mean smoothing method and the backtracking fine positioning .

In this paper we investigate relationship between parallel efficiency and grain of calculation load and accuracy for analysis of acoustic propagation further.
By adding the following rules, it can decreases number of rules from 256 rules to 32 rules
In order to keep load balance in each domain, a domain is divided into subdomains which have the same number of cells individually.
Therefore if number of processors increases, speed up ratio decreases in case of 11x11 and 21x21 models.
Number of space divisions is 601×601.