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Finding the working limits of process variables Although the deformation of composite material appears to be simple, the process of determining the flow stress becomes complex due to the presence of large number of parameters which have been interacting simultaneously.
When the effects of the Orwan mechanism, the strain gradient plasticity, the grain refinement of matrix and the high dislocation density due to thermal expansion mismatch are taken into account, the calculated stress- strain curve of the composites is consistent with the experimental results in the low strain region (0.2).
[10] Z.Xue, Y.Huang and M.Li, Particle size effect in metallic materials: A study by the theory of mechanism-based strain grain gradient plasticity, Acta Materlia, 50 (2002) 149-160.

Fig. 2 XRD pattern of No. 1 specimen Fig. 3 XRD pattern of No. 2 specimen Fig. 4 XRD pattern of No. 3 specimen Fig. 5 XRD pattern of No. 4 specimen Fig. 6 XRD pattern of No. 5 specimen Fig. 7 XRD pattern of No. 6 specimen Table 1 Features of hand specimens and thin sections Number of Specimen Features of hand specimen Features of thin section No. 1 White, massive structure.
There is nearly no grain in naked eye.
The texture type of jadeite is granular-prismatic crystalloblastic texture and mylonitic texture (Fig. 9c).Jadeite crystals are very fine-grained.

Coal seam roof and floor more stable, coal seam roof is quartz, feldspar, fine-grained sandstone, the horizontal and wavy bedding of rock are development, the thickness of coal seam roof about 6~7m.
In the upper part of immediate roof is about 14m medium-grained sandstone[1].
The distribution of ground crack caused by 2304 working face mining of Han jia wan coal mine was: crack approximately parallel to working face, this kind of ground crack mainly distribution at the central of gob, crack was approximately parallel to working face, it appeared ahead of the working face mining, when the working face passed, crack reached the maximum,and then be closed as the time passed by[8]; cracks near open-off cut and the top slopes, the number of crack at top slopes is larger and length and width of crack is larger, and the extension direction of crack is generally perpendicular to tilt direction of slopes, there is only a small fissuring crack at the base position of bottom slopes.

It has many eximious characters such as high purity, small grain size, narrow grain diameter distributing, large specific surface, good reaction activity, high adsorption capacity, excellent heat stability, and so on.
Through large numbers of experiment, two feasible schemes were confirmed finally.

Moreover, with the number of wearable devices carried by a person increases further, the gateway becomes more useful for power saving in overall.
They employed hash-chain based key updating method and proxy-protected signature to achieve efficient secure transmission and fine-grained data access control.
Last but not least, the security strength for all devices is the same, which cannot provide fine-grained security managements for distinct devices.

During welding of a WSTE-51 steel, the V contributes to precipitation hardening by forming carbonitrides at the weld joint as well as a grain refiner [1].
Welding procedures for the WSTE-51 steel plate Electrode Number of passes Voltage (V) Current (A) Pre-heating Welding speed Heat Input Tenacito 60 diameter 4 mm 16 21-25 135-160 175°C 160 mm/min 1.2 kJ/mm After welding, both X-ray and ultrasonic test, applying the usual 70° headset and frequency of 2 MHz, were used for internal inspections.
The presence of V in the WSTE-51 steel promotes fine carbide precipitation in the grain boundaries and favors the nucleation of cracks to accommodate the thermal stresses [2,15].

Large number of bulk properties of kaolinites is determined by the surface properties of the kaolinite.
Presence of deep cracks through the sheets cause a strong decrease in grain size from 45 nm to less than 2 nm as revealed in Fig. 1C.
(C) Profound cracks through the sheets cause a strong decrease in grain size (D) the margins of this small particle fan out and roll up, also leading to a delamination of the particle.

Introduction Semi-solid thixoforming processes rely on a material microstructure made of globular solid grains more or less connected to each other, thus forming a solid skeleton deforming into a liquid phase.
During processing, the material structure changes with the processing history due to the agglomeration of the particles and the breaking of the grains bonds.
Acknowledgment The authors wish to acknowledge the Wallon Region for its financial support to the THIXOWAL project (Marshall Plan/Mecatech program, convention number 6315) in the context of which this work was performed.

Although no universal constitutive equation exists for die compaction, a number of general features are expected (or assumed) when modeling confined granular materials under load in a uniform and axisymmetric die.
In addition, it is known that at low applied stress, granular systems are locally inhomogeneous on a grain by grain scale and geometric complexity is expected to cause considerable deviation from these simple assumptions.

The grinding wheel topography, cutting edge shape parameters, and wheel grains position distribution are random, not to mention that grinding process is non-linear and indeterminate.
But it can't always attain a satisfying machining result because of the comparative limitation of the knowledge rule of the expert system and the limited number of the training sample of the fuzzy neural networks.
Meanwhile the dynamic machining process cannot be completely controlled since the grinding process is influenced by many uncertain factors, such as the random of the wheel topography, cutting edge shape parameter and wheel grain position distribution, and some unknown grinding principles.