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Instead of allowing decryption conditionally on the satisfaction of a single threshold gate (whose inputs are the matching attributes in the ciphertext and the key), Goyal et al. [4] proposed an ABE scheme that provides fine-grained sharing of encrypted data.
Recently, Chase [7] presented a scheme which allows any polynomial number of independent authorities to monitor attributes and distribute secret keys.
Efficiency: The number of exponentiations, group elements that compose a user’s private key and the number of group elements in a ciphertextin will be linear in the number of elements in the identity’s description.
In addition, the number of group elements in a private key or in a ciphertext grows linearly with the size of the identity.
Waters, Attribute-based encryption for fine-grained accesscontrol of encrypted data, Proceedings of the ACM Symposium on Information, Computer and Communications Security, October 30-November 3, New York, USA.

Concurrently, quite high requirements with regard to high number of cycles without any damage are demanded for many applications.
The majority of authors (e.g. [3,4]) concluded that for good fatigue properties a high amount of fine-grained, equally distributed particles is necessary.
In addition, the material used in [4] exhibited a higher grain size of the aluminum matrix as well as a smaller particle size of the reinforcement.
However, also different grain sizes [7] and matrix stiffness should be taken into account to influence the fatigue life.
Fig. 5 (a) shows the parameters versus the number of cycles for a short fiber reinforced specimen (20s(Q)).

The number of macro-soil aggregates after dry sieving were far more than the number after wet sieving.
As a core element, soil is the main place for physical, chemical and biological process taking place, and also important link between atmosphere, hydrosphere, biosphere and lithosphere[1].As the basic unit of soil structure, the aggregate is the key index determined the speed and the rate of soil erosion, compaction and soil hardening, and also has an influence on soil porosity, water capacity, permeability and anti erodibility[2].The aggregate not only play an important part in soil fertility regulation and maintain soil productivity but also has significantly relationship with soil anti erodibility and environment quality[3,4].Generally, soil structure evaluation can be morphological description and evaluation the number and quality of aggregate with evaluation indexes include WSAC, MWD, GMD, PAD and FD[5,6].
Soil organic matter(SOM) was determined by wet oxidation (potassium dichromate oxidation with external heating). 3 Results and discussion 3.1 Soil texture content According to the American soil grain size classification standards, red bare soil has been divided into clay(＜2μm), silt(2～50μm) and sand grain(50～2000μm).
Clay soil was sticky, poor cultivation performance, lack of macropore between soil grain and also lack of ventilation and permeability. 3.2 Soil aggregate content Dry sieving method was used to assess the soil elastic- stable aggregate content under natural conditions which avoid destruction of transient and temporary organic cementing substance.

For high speed steels, distribution, grain size and shape of carbides are also important factors, increasing the cooling rate decreases primary and secondary dendrite arm spacing, and refines MC eutectics as a consequence[3,4].
The larger primary carbides are distributed in the clearly visible grain boundary, which size is about 2-3µm.
The number of the second carbides is small in microstructure, which is concerned with keeping warm 2 steps after the spray forming run, reduce the cooling speed of spray forming ring to control the nanoscale fine, dispersal carbide separate out from matrix.
International Materials Reviews, Volume 46, Number 2, February 2001 , pp. 92-115(24) [4]H.F.
Volume 20,1989 Number 10, 2133-2148

The base metal displays an aggregate of well-defined ferrite-pearlite bands while the HAZ is characterized by a network of coarser grain boundary ferrite with colonies of fine-grain acicular ferrite.
Faster cooling of the weld metal region results in fine-grained Widmanstatten ferrite microstructure.
Average hardness numbers for BM, HAZ and WM is 150, 209 and 172, respectively for the as-received welded plates.
The resulting Vicker’s hardness number for BM, HAZ and WM following 1200-hour aging is 124, 160 and 131, respectively.
Conclusions Results of this study on welded A516-Grade 70 steel joint show that; - Average hardness numbers for BM, HAZ and WM is 150, 209 and 172, respectively.

Therefore, a number of research works had focused in possibilities of taking magnesium alloys as bio-absorbable implants [3-5].
The matrix became uniform and grain boundaries became clearly, as Figure 1(c) and (d) shown.
Subsequently, lots of β phases precipitated within the grains and on the grain boundaries as Figure 1(e) and (f) shown.
When the number of β phase is small and distributes discontinuously, β phase mainly acts as negative electrode and accelerates the corrosion rate.
On the contrary, if the number of the β phase is large and continuously distributed in the matrix, it mainly acts as corrosion barrier and decrease the corrosion rate.

Varying angle � i is the angle FBx, the maximum value of it along the arc AFB is Journal Title and Volume Number (to be inserted by the publisher) 171 contact angle � .
Eq.2 can be expressed in dimensionless form with X=vf x/4 � , Z=vf z/4 � , and Peclet Number L=vf lc /4 � so that mean temperature rise is T q2 vk T f � ��� �� = . (4) Uniform Heat Flux Model [3].
Along the grinding zone, the chip thickness of the grains is not uniform, it has the maximum value at approximately the front edge of the grains and approaches zero at the tail, so a triangular heat flux distribution on the grinding zone is more reasonable.
Workpiece z x A E B B A V 50 100 150 200 500 700 900 1100 1300 1500 Tmax(Deg.C) Qw(mm/mms) Measured Calculated Fig.3 Triangular heat flux model Fig.4 Measured maximum contact temperatures in burn-out conditions Journal Title and Volume Number (to be inserted by the publisher) 173 Results and Discussion The measured grinding temperatures were shown in Fig.4.
The grinding parameters and conditions of the HEDG, such as wheel-workpiece contact geometry, wheel status and speed, specific removal rate and thermal properties of the workpiece, abrasive grains and grinding fluid, etc. must be selected correctly and optimized in order to prevent grinding burn-out of workpiece surface in HEDG.

Components of multifractal spectrum were calculated using the following formula (2) where is characteristic linear size of the cell.The value of multifractal when q = 1 was determined using a separate formula (3) Multifractal spectrum components were used to calculate the number of indicators of structural organization of material, in particular (4) (5) With their help, the estimated degree of order and periodicity of the microstructures were evaluated.
The grain boundaries are active channels of diffusion conductivity; thus, during the analysis of microstructures, formed as a result of chemical and thermal processing, of local doping and structural degradation due to the diffusion of hydrogen and oxygen it is preferable to use the indicator (p).
Plastic properties of material are largely determined by the grain size; in this case the multifractal spectra calculated using the total area of microstructural objects can be used.
The highest value Kq corresponds to non-homogeneous structure, in which there isa significant number of components with large and small structural indicators.
As a measure during the calculation of multifractal spectra of stainless steel 12X18H10T after laser treatment, the boundaries density has been accepted, given that the development of grain boundaries has the most active influence on the deceleration of the mobility of the moving dislocations during plastic deformation and determines the degree of increase in microhardness when hardening metals.

Moreover, in order to obtain grain and firewood, people cultivate on slope land, destroy forest for cultivation and overgraze, which has aggravated soil erosion in turn.
In 2005, the total number of poverty-stricken counties in the region accounts for 17.2% of that of the country, while the impoverished population with annual income under 900 RMB accounted for 8% of the total population in the region.
A series of key ecological engineering programs including slope farmland transformation, afforestation and grain for green have been implemented in the serious soil erosion regions since the 1980s.
By the end of 2000, grain production has been increased 1.85×109 kg each year due to soil and water conservation in Haihe River basin.
So a large number of farmers get rid of poverty and have improved their living conditions.

Introduction Among all known techniques of dislocation hardening, the one based on grained structure refining can be particularly emphasized.
Its main advantage is a beneficial effect of grain refining not only on mechanical properties, but also on characteristics of plasticity, crack resistance, wearability, and corrosion resistance of metallic materials.
At present the most advanced approach is the one based on the grain structure refining at the stage of its formation from the melt due to the introduction of alloying ultrafine particles serving as crystallization nuclei [1, 2].
Thus, the number of active crystallization nuclei in the melt increases, and the melt structural elements are refined through modification type II [3].
The presence of a large number of crystallization nuclei in the melt suppresses liquation and shrinkage processes, with the temperature range being considerably reduced and the crystallization rate being increased.