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In the model the material is discretized in terms of convex polygons which represent grains having three continuous degrees of freedom, i.e. the center of mass coordinates and a rotation angle.
Figure 3(a) presents the average number of cracks identified by our algorithm as a function of v.
Fig. 3: (a) Evolution of the number of radial cracks as function of the loading speed.
Increasing the speed the number of cracks increases, furthermore, they develop side branches.
In the high speed limit fragmentation occurs and the sample breaks up into a large number of pieces.

It includes contributions from industry, as well as academia, and is a testament to the number of people in aluminum research and technology with whom David has collaborated, and whom he continues to influence.
As a Research and Principal Scientist at Alcan, David worked in a number of different areas.
When he first joined Alcan, he investigated the formability of a range of ultrafine grained alloys.

Firstly, failure models of survivable system were formally described based on stochastic Petri nets, in which a number of measurable index parameters for rejuvenation were also given out.
However, according to a large number of related literatures about survivability technology from domestic and foreign, we found that the existing researches more concerned about the definition of survivability [1], model analysis [2], survival assessment [3], formal modeling [4], survivability protection [5] and so on, a large number of work were taken emphatically on the resistibility and identifiability of survivability, but the research on the recoverability mechanism of survivable system is confined in the CMU, CERT/CC, DARPA and several other research institutions, and the current research in this area has not been reported.
Mean Time between Faults.Mean time between faults, MTBF is approximately equal to the ratio between the normal service time and the number of failures, that is (4) Four-level Rejuvenation Strategy System-level.The implementation of system-level rejuvenation strategy will terminate the operation of a system, the several key services offered by the system are not available now, which should be paid a certain expenses.
Fig.5 The rejuvenation cost under different failure probability Summary In order to make a reasonable fine-grained emergency recovery strategy for survivable system, a method of four-level recursive emergency rejuvenation for survivable system was proposed, which made use of SPNs to formally describe the implementation process of the recursive reboot recovery.

By calculation, the previously determined optimal range of values of the frequency of control actions of 40÷60 Hz was confirmed, which makes it possible to ensure the minimum depth of penetration of the base metal and obtain a favorable structure in the heat-affected zone, prone to the formation of a coarse-grained structure.
This is due to the fact that the function of change in the thermal power in the base metal is characterized by a large number of controllable parameters, which does not allow the use of known techniques for sources of variable power for calculating the distribution of heat in the weld and near-weld zone [13, 14].
A decrease in the area of isotherms in the temperature range 900÷1100 °С will lead to a decrease in the size of the austenite grain in this zone and will allow the formation of more favorable structures.
Reducing heat input into the heat-affected zone in the temperature range 900÷1100 °С provides a finer-grained structure. 3.

The results indicated that sweet sorghum straw bio-feed fermented by the Compound Microbial Agent in bags could increase the feed intake (11.4%) and milk yield(14.2%) compared with the control group, it also has improved milk protein (14.03%) and butterfat rate (16.3%) ,and has reduced the somatic cell's number(5.15%) compared with the control group.
Introduction Sweet sorghum is the best multipurpose crop for simultaneous production of grain from its earhed as food, sugary juice from its stalk for making syrup, jaggery or ethanol and bagase and green foliage as an excellent fodder for animals[1].The experiment is aimed at researching the feeding effect of the sweet sorghum slag fermented in bags by the Compound Microbial Agent which is developed from the protein-enriched yeast and cellulose–enriched Aspergillus niger irradiated by Ion Beam of 12C6 + [2], and specifically the evaluation is based on the feed intake[3], milk yield[4], milk-feed ratio and milk quality[5] of the cows.
The test results indicated that The content of milk protein and butterfat rate have increased by 14.03%( Table 4) and 16.3%( Table 5) respectively and the somatic cell's number has reduced by 5.15%( Table 6) when the cows are fed on the sweet sorghum bio-feed compared with the control group.It has promoted the cow’s capacity to produce milk, and also improved the quality and flavor of dairy product.
The content of milk protein and butterfat rate have been increased and the somatic cell’s number has been reduced.It has promoted the cows’ capacity to produce milk, and also improved the quality and flavor of dairy product.
Table4 Variation of the milk protein content of milk samples Experiment period Experiment group Control group Content of milk protein（%） Content of milk protein（%） Control period 2.39 2.34 Transitional period 2.42 2.36 Trial period 2.78* 2.35 Compared with control group * P＜0.05; Table5 Variation of the butterfat rate's content of milk samples Experiment period Experiment group Control group Content of butterfat rate（%） Content of butterfat rate（%） Control period 1.71 1.69 Transitional period 1.84* 1.65 Trial period 1.99** 1.74 Compared with control group * P＜0.05; Table5 Variation of the somatic cell's number of milk samples Experiment period Experiment group Control group Content of butterfat rate（%） Content of butterfat rate（%） Control period 4231 4332 Transitional period 4256 4532 Trial period 4013* 4427 Compared with control group * P＜0.05, ** P＜0.01; The Compound Bacteria Agent developed from the feed strains such as yeast, trichoderma and Aspergillus niger screening

The nanocomposite coatings composed of nanocrystalline TiC grains embedded in hydrogen free amorphous carbon a-C matrix (nc-TiC/a-C) were deposited by magnetron sputtering on the two substrates, oxygen hardened Ti-6Al-4V alloy and heat treated VANADIS 23 steel.
Large volume of grain boundaries restricts initial crack sizes, and it helps deflect and terminate crack growth.
Microstructure Oxygen Hardened Ti-6Al-4V Alloy The microstructure of the oxygen hardened alloy consisted of α phase (hexagonal close-packed; hcp) grains up to 15 μm size and β phase (body-centred cubic; bcc) grains with size up to 5 μm.
Heat Treated VANADIS 23 Steel The microstructure of the VANADIS 23 steel consisted of Fe α grains (bcc) with size in the range 4÷15 μm and numerous carbides (Fig. 1).
Friction process was very stable and only small fluctuation of coefficient of friction was observed within full 20000 numbers of cycles (Fig. 10).

Despite this variety, crystal chemistry of these components revolves around a small number of crystal structures.
Nevertheless, its solid solutions with spinels such as MgCr2O4, MgAl2O4 become more resistive, because the substitution of octahedrally coordinated Fe2+/Fe3+ by Cr3+ or Al3+ reduces the number of sites available for electron hopping.
Later, a number of European and American manufacturers found acceptable reproducibility of electrical characteristics for Ni–Mn–Cu based ceramics sintered in open air.
The cationic vacancy model is based on a preferential oxidation of the grain boundaries on cooling from the sintering temperature.
Basically, metal vacancies are formed at the grain boundaries, according to: 1/2O2« OoX+1/4VA'' +1/2VB'''+2p∙ These vacancies diffuse preferentially to the B-sites inside the grains, decreasing the number of hopping pairs in octahedral sites, which leads to an inevitable increase of the total resistance.

Thus, a large number of superparamagnetic particles (phases) obtain stable magnetic moments and are involved in creating of the remnant magnetization of the sample.
It is likely that, the magnetic moment of a sample is mainly due to the large number of small particles, which according to their size should be superparamagnetic at a given temperature.
Consequently, the magnetization of dispersed in the amorphous coating clusters, which are the systems of interacting particles, or hetero-structures will be determined by the grains, for which the Let's observe weakly magnetic particle (phase), that has a stable magnetic moment, for example, goethite Ms ~ 5 G or hydrogoethite Ms ~ 0.5 G.
This way, an increasing number of small volume strongly magnetic particles (phase) contribute to the magnetic moment of the whole sample.

Introduction Torsion working is the convenient and simple processing for work-hardening and grain refinement of the material [1].
Fig. 3 shows the number for unit area (0.25 mm2) of α phase in each microstructure.
The extruded sample and the ECAPed sample are almost the same numbers.
However, there are quite a lot of numbers of α phase of the twisted sample.
Fig. 3 Number of α phase.

Mullite has a refractive index of 1.64 but its low concentration and relatively coarse size of its grains lessens its affect on translucency.
The number of samples used varied between eight and ten for each binder level and sintering temperature.
Figure 4 shows the chemically etched (5% HF solution) microstructure of the novel whiteware, which consists of tabular anorthite grains (1-5 µm) along with needle-shaped mullite grains (3050 µm) in a calcium aluminosilicate glass.