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Coarse aggregate is gravel of the first grain composition with a maximum diameter of 20mm.
Table 1 fracture toughness test values of wedge splitting specimens/Mpa.m 1/2 试件种Type specimen Condition 工况编号number 有效试件数量Valid specimen number Specimen 试件尺寸size 缝高比Relative crack length Test 试验平均值averages 普通 Common 混凝土 concrete PC1504 PC1504 6 6 150×150×150 150 × 150 × 150 00.4 0.750.755 PC1505 PC1505 22 150×150×150 150 × 150 × 150 0.0.5 0.620.628 PC1506 PC1506 33 150×150×150 150 × 150 × 150 0. 0.6 0.620.624 As can be seen from Table 1, relative crack length has a certain influence on fracture toughness of concrete, the general rule is that fracture toughness of concrete decreases slightly with relative crack length increasing.
表2混凝土试件断裂韧度计算值/Mpa.m 1Table 2 Calculated value of fracture toughness of concrete specimens/Mpa.m1/2 试件种类 Type specimens 工况编号 Condition number 有效试件数量Valid specimens number 缝高比Relative crack length 试验值 Test value （式5）(Equation 5) 理Theoretical value 偏差Deviation /%% 普通混凝土 Common concrete PC1504 PC1504 6 6 0.4 0.4 0.7550.755 0.755 0.755 PC1505 PC1505 2 2 0.5 0.5 0.6280.628 0.738 0.738 17.5 17.5 PC1506 PC1506 3 3 0.6 0.6 0.6240.624 0.712 0.712 14.1 14.1 从表2可以发现，本文基于Hu公式得到的混凝土断裂韧度公式（5）计算结果与实验值偏差大约在14-18%。

It has been responsible for a large number of service failures across a wide range of applications.
It is consisted of predominantly equiaxed α grains, lamellar transformed α plates, and fine intergranular β phases with the percents of 65% and 35%, respectively.
Note that three distinct regions are numbered and the main position for crack initiation are identified by an angle.
Location Ti Al Si V Fe Mo Na P O Matrix 89.39 7.75 0.25 2.61 --- 1.18 --- --- --- Debris 32.24 5.89 2.43 1.52 2.42 1.18 0.48 0.4 52.8 Number Position HV Airfoil 359.33 1st fracture Root 335.8 Airfoil 353.25 2nd fracture Root 338.17 Sample YS [MPa] UTS [MPa] Elongation [%] Reduction of Area[%] Standard (min) 862 931 10 25 1st fracture 961 1093 11.8 39.2 2nd fracture 984 1025 16 33 Figure 6: Micro-fractography of the 1st cracked blade fracture surface showing the main crack and debris in mouth of crack.

It measures the lattice spacing in a range of the diffraction angle 2q, 150°-160°, for a number of Ψ angle tilts.
The local grit loading was calculated using the monitored grinding forces divided by the active grit numbers, whilst the contact area between the grit and workpiece material was estimated, using the average grinding chip geometry, determined by the average grinding chip thickness.
The maximum chip thickness can be estimated using the equation: (10) r is the ratio of the chip width over thickness, which is estimated as; Nd, is the active grain number per unit area.

Experimental results indicate that open porosity decreased and bulk density increased with the numbers of infiltration cycle.
Morphological observations also show that the number of open pores at surface site for these materials decreased and they exhibited a denser and smoother morphology as the number of infiltration cycle increased.
Introduction: Boehmite (�-AlOOH), an aluminium hydroxide, is one of the candidate precursor materials for fine grained low temperature alumina ceramics.
As expected, the open porosity decreased and bulk density increased as the number of infiltration cycles increased.
Conclusion The open porosity decreased and bulk density increased with the numbers of infiltration cycle.

It decomposes the mesh in different directions following the order of xyz into a specific number of domains according to user’s configuration.
Thus after being decomposed by Simple method, each of the domains still contains a very large number of cells.
The maximum total number of boundary vertexes is.
Figure 6 Decomposition time comparison Number of faces generated by the decomposition and percent of the max number of cells of all the domains above the average number can reflect quality of decomposition in the view of communication overhead and load balance [7].
A Coarse-Grain Parallel Formulation of Multilevel k-way Graph Partitioning Algorithm [C].

Simulation program design of random loads In simulated drum cutting process, the following questions should be considered: (1) Simulating cutting pure coal and rock layers by corresponding mechanical model; (2) Determining location and number of rock sandwich according to geological data, simulated cutting rock sandwich by rock mechanics model; (3) Hard parcels are randomly distributed in the seam, but for a coal seam, its size, shape and location is determined [6].
Simulation and result analysis of random loads Taking a certain type continuous miner as an example, parameters used in the simulation are: drum diameter 0.915 m, drum width 3.35 m, rotating speed 38 r/min, cutting depth 0.58 m, boom length 6.445 m, swing speed 3.42 m/min; there is a layer coarse-grained sandstone along the seam, the upper and lower limit coordinates is:＝380 cm,＝350 cm; Parcels are sulfide type and distribution in Gamma function, there are 40, and the mean size of the long axis is 10 cm.
It can be found from results that loads of the drum are changing regardless of how is cut object, and there is significant volatility, which is reason of different pick number at each time, construction characteristics and physical properties of coal and rock.
Acknowledgements This work was supported by: 1National Natural Science Foundation-funded Project (59774033); 2Project of Creative Team for Liaoning Provincial Education Office (2007T068); 3Project guiding scientific and technological research of China Coal Industry Association (MTKJ-08-311); 4Liaoning Province Key Laboratory of large-scale mining equipment (the second batch of Science and Technology projects of Liaoning Province, 2008403010). 5Project of 2009 Safety Technology Development Program (Safety Production Supervision Bureau of Liaoning Province, the file number: [2009]88).

However, it is well known that the surface charge properties of different ceramic powders vary with the type of powder and in some cases even with the producer[7,8] ,so a number of studies on powder surface modification processing have been carried out.
Curve 1 is the spectrum of origin powder, the peak in the wave number 892.9 cm-1 is Si-N bond stretching vibration, while the 3474 cm-1 peak related with the O-H stretching vibration, due to hydrolysis of silicon in the air, which results of the O-H bond.
a c b Fig.3（a） The SEM of original Si3N4 powder Fig. 3 shows the morphology and grain size of Si3N4 powder without modifier and powders modified by tartaric acid and PEI.
At the same time we can see the powder modified with PEI are spherical trend, diamond, flaky particles significantly reduced the number of spherical particles increased significantly.

Patch is the gathering of species, and its type, scale, size, location, shape, edge and number not only have great influence on the structure of the landscape, but also have great effect on the ecological process.
During the operational process, it is necessary to consider seven ecological characteristics of landscape, such as large patches of natural vegetation, size of grain, the risk of proliferation, variability of gene, ecotone, small patches of natural vegetation, corridors, etc.
However, it can increase a small number of patches of agriculture between the large patches of natural vegetation and buildings.
For instance, in the construction of green area patches, great attention should be paid on the construction of large-scale green area patches, while arranging small green area patches as supplements; the more the number of green area patches, the higher the diversity of eco-system and species; the closer the connection between patches, the frequenter the species exchange in patches, the stronger capacity of resisting disturbance of the whole biotic population.

This comprised some 50% of the total number of contributions.
Vacancies at grain boundaries appeared to be shallow traps for positrons.
A number of other topics were studied, including: effects of the As-vapour pressure on vacancy concentration in GaAs, VSi in electron irradiated 6H-SiC, activation of dopants in B- and Al-ion implanted SiC, voids in Al- and N-ion implanted ZnO, Zn associated defects in GaP with Znimpurities.
Final Remarks In this conference there was a considerable number of contributions on metals and metal alloys, a little more, relatively, (23% of the total) than in ICPA12 (20%) [1].

High demands on the accuracy and quality become strict if it is necessary to manufacture elements with small-size periodic profile, for example, fine-grained tooth-wheels for transmission nodes or slots with a complex profile and etc.
The appearance and reamer in diameter of heavy-duty mill with the constructive feed (a); reamer in diameter of mill with “helical backing-off” (b) Тhis tool has a number of advantages and disadvantages, both in terms of operational characteristics or dynamics of the machining process as well as from the viewpoint of physical processes occurring in the zone of contact of the tool with the work-piece.
For example, increasing the feed per tooth by decreasing the number of teeth in the annular circular row should significantly reduce tool life, in the design of which axial constructive feed is laid.
A number of papers [3,4,5] has been devoted to the research in the field of the tooling design and tooling operation with constructive feed, however, the questions of their wear properties are not lit enough.