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Actually, the uniformity of burning for all propellant grains are directly influenced by many factors such as the variation in shapes and dimensions from one grain to another grain, and the difference in the ignition condition as well as the circumstance that the burning charges.
(3) where i is the different data point number in the curve of y- Zp.
The propellant charge is composed of double-base tubular propellant grains.
Table1 Size of grain in 100mm gun propellant charge.
By this new model, the complicated form function calculation is unnecessary, and the deviation of web size from one grain to another grain can be avoided.

Ultra fine grains are obtained by the process and the subject regarded in nano-structure applications.
There are several articles about the grain size effects on the mechanical properties [1,2,3,4,5].
Then the vertical channel was machined at the bottom of the Number 1 part of Figure 2 in a milling machine.
Langdon: “Principles of equal-channel angular pressing as a processing tool for grain refinement”, Progress in Materials Science 51(2006) 881–981
Mughrabi : “An overview: Fatigue behaviour of ultrafine-grained metals and alloys”, International Journal of Fatigue 28 (2006) 1001–1010

Besides, in Cloud computing, data owners may share their outsourced data with a large number of users, who might want to retrieve data by decrypting them and need a lot of computation overhead.
These encryption approaches are also not sufficient to support the enforcement of fine-grained access control policies [4].
The time decay process can be done after a period of time or after learning some number of cases by fading old trust before taking new ratings into consideration.
The architecture of this approach based on encryption for fine-grained access control over encrypted data is shown in Fig.2.
XACML (eXtensible Access Control Markup Language) is the OASIS standard and XML-based language for defining complex and fine-grained access control policies.

Blasting has several advantages, e.g. reuse of abrasive grains, small environmental loads, low cost of equipment, high machining efficiency[3].
Abrasive grains shot through the nozzle with a setting traverse feed of a nozzle interfere in the rotating workpiece surface with adhesive mask film.
Abrasive grains are sucked up with Ventury effect by air supply from a compressor.
It is caused by the double blasting time in the process with both offsets depend on the number of times in the traverse nozzle feed.
Yamamoto: Effect of abrasive grain on surface finishing characteristics for brittle materials, J. of JSAT, 46, 4(2002), pp.195 (in Japanese)

Up today, a large number of studies have been carried out on the 7XXX series alloys, mainly focused in conventional alloys, such as the 7050 and 7075, with an alloying element concentration of approximately 12% (%wt, the same below) [8-12].
Table 1 gives the serial number and the corresponding composition of the various aluminum alloys.
For the four kinds of alloys in Figures 3 and 4, with the decrease of the uniformity degree, the residual phases at grain boundaries were gradually decreased, which results in the increase of other elemental compositions in the interior of grains and thus aggravates the intracrystalline lattice distortion.
This should be attributed to the formation of hard spots during the homogenization treatment, caused by the diffusion of alloying elements along the grain boundaries and into the grains.
Grain structure and quench-rate effects on strength and toughnessofAA7050 Al-Zn-Mg-Cu-Zr alloy plate [J].Metall.Trans.A,1995,26(9):2481

This fatigue experiment would adopt the stress control mode, and so is the method to identify the fatigue span: with the increasing number of loading, vertical deformation of specimens changes from stable stage to rapid increasing stage, and corresponding stressing numbers at the turning point is calculated as fatigue damage times[7].
Fatigue performance experiment of cold recycled mixture According to the mathematical statistics theory, if average fatigue life of limited number of specimens is used to measure a material fatigue life, it cannot ensure safety.
(1) Among it, n is the number of specimens, is the "relative standard normal partial quantity" related to survival rate .
As for any specific survival rate, there could be calculated value, thus logarithmic safety life of p number of individual specimens in maternal material bigger than .
Tab.5 Comparison of fatigue performance between cold recycled medium-grain mixture and hot asphalt mixture Mixture type Splitting strength of 15℃（MPa） Stress ratio Average number of fatigue life Standard deviation of logarithmic 2#( Foamed asphalt 60%RAP) 0.50 0.1 5.0493 0.22 0.3 4.5057 0.15 0.5 3.6659 0.09 0.7 3.4777 0.10 4#( Emulsified asphalt 60%RAP) 0.56 0.1 4.9137 0.19 0.3 4.3088 0.21 0.5 3.8082 0.16 0.7 3.1611 0.04 No.Esso70 Medium-grained 2.00 0.25 4.2622 0.32 0.3 3.8799 0.10 0.4 3.4616 0.18 0.5 2.9983 0.12 0.6 2.9406 0.1 No.Shell 70 Medium-grained 3.26 0.25 5.0848 0.26 0.3 4.5758 0.16 0.4 4.1303 0.14 0.5 3.4358 0.11 0.6 2.8644 0.03 The analysis shows that it is not sure that the fatigue performance of recycled material is better than hot-mix asphalt mixture.

It can be summarized that the number of longitudinal crack in length range 0-17 mm parallel to the roll-casting direction was higher than transverse crack in length range 0-7 mm as illustrated in Fig. 1, and the number of the longitudinal crack was ~2.1 times than transverse crack.
Fig. 1 Statistic of crack distributed on roll cast strip surface (Sample number: 30).
It can be seen that all the cracks including longitudinal and transverse crackswere initiated from the grain boundary, but the crack propagation direction was different.
Besides, it was observed that the grain size near the crack was larger than the normal region of processed strip.
As measured, the thickness of columnar grains was determined to be ~0.63 mm in the cracked region, and was only ~67 % of the thickness compared to columnar grains in the un-cracked region.

The alloys were held at 750 °C, for a number of different holding times up to 7 hours.
It has also been suggested that oxides may be used to facilitate grain refinement by acting as a nucleation site for solidification [10].
EDX showed that the alloying additions tended to form intermetallics at grain boundaries, with none of the alloying element found within the grains themselves.
EDX analysis also suggested that the oxide formed was Al2O3, only containing small amounts of the alloying elements when the oxide on the surface was near a grain boundary.
Further study of the grain structure of the alloy samples needs to be undertaken to ascertain if they would be useful as nuclei.

The quantitative analysis of the tests highlights the point that with the same fabric, the same pattern and the same grain, the top and under collar differences in tested points of a lapel are obviously related.
Select six clothing fabrics, the same as above-tested ones, and number them.
Iron the fabric, then according to the demands of clothing industrial layout, cut the fabric along its grain, with the center of the collar as the symmetric line.
Meanwhile, because of the symmetry between B and B’, we can get a even number of B and B’’s relative displacement and get data E; similarly, the even number of C and C’’s relative displacement is data F.
After the collection and analysis of the data, the following conclusions can be reached: With same fabric, same pattern and same grain, the top and under collar differences in tested points of a lapel are obviously related.

In most cases fine fillers are used for controlling grain structure and voidage of concrete solid phase.
Today, there are a huge number of grinding units.
Granite is activated the worst of all, the number of Bronsted sites on the surface does not increase 1.6 times.
Lesovik On the choice of man-made sand to produce composite binders and fine-grained concrete.
Fine-grained road concretes with fillers based on technogenic raw materials: Thesis (Candidate of Technical Sciences). 2005.