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For this type of machining are generally three kinds of tool wear: attritious wear, grain fracture and bond fracture.
It has been reported that the attritious wear has the least influence on the tool geometry, being represented only by the abrasive grains dulling due to the rubbing against the work-piece.
On the other hand, the grain fracture and bond fracture influences the cutting tool geometry.
The first one involves the grain fracture, resulting a self-reshaped tool and the second one involves the abrasive grains dislodging from the binder, both of them leading to the loss of shape and size of the cutting tool [5, 6].
Accordingly with these results, the number of holes that can be drilled increases by decreasing of vibration amplitude and increasing of vibration frequency.

All specimens are immediately water cooled down to avoid the occurrence of recrystallization and grain growth so as to retain the tissues after hot deformation.
With the increase of strain rate, work hardening effect enhances on the one hand due to the increasing number of dislocation generated per unit time, while the strain softening effect decreases on the other hand since the time for strain softening reduces, which results in the increase of peak stress and peak strain.
Some sites are still the deformation matrix that never has recrystallized, some are newly-formed strain-free R-grain (recrystallizing grain), others are R-grain but has deformed.
The reason lies in the fact that the adequate DRX and grain refinement at the first-stage deformation contribute to the occurrence of DRX at the second-stage.

Table 1The relative amount of different types chemical bondings for C 1 S, chemical composition, amorphous carbon content, stoichiometric number x and y in HfCxNy (HfCx) coatings at different N2flow rate (FN2).
And Fig. 4 shows all the peaks tend to shift to larger angle with increasing N content, which indicates more solutionof N in HfC(N) grains or more presence of HfN(C) phasein films.
Grain sizeestimated by the Scherrer formula only fluctuates in a small range from 3.3 nm to 4.0 nm.
It might be the high bias voltage that the ions bombard the substrate with during films growth that causes serious grain refinement, hence all the grains maintain at a low dimension.
Fig. 7.Specific friction rate for films as a function of FN2 Fig. 8.Cross profiles for wear tracks for films deposited at FN2 (a) 0 (b) 2 (c) 4 (d) 8 (e) 12 sccm Conclusions The HfCxNyfilmswere deposited by sputtering aHf target in a mixture of discharging N2,Ar and CH4, and the N content in films is accurately controlled by changing the N2 flow rate.Theanalyses of XRD and XPS suggest introduction of N into the films contributes to the presence of FCC-HfN and meanwhilesolid solution FCC-HfC(N) grains also form in the film.

Choi et al. used nanocrystalline matrix powder whose grain size was reduced by ball milling the powder for 24 hours.
It is known that the nucleation and growth of precipitates may progress much faster when grain size is reduced because the fine structures cause enhancement of aging kinetics [24].
At the same time, the grain boundary diffusion will be higher in the case of smaller grains due to an increased density of grain boundaries.
Acknowledgement The authors would like to acknowledge the financial support for this work from King Abdul Aziz City for Science and Technology (KACST) through research project number ARP-28-122.

To improve the adhesive properties and to ensure higher density, the fine-grain additives are usually used (such as silica fume, micro-limestone).
The used slag (SL) comes from the heap near the old thermal power plant and was delivered in the grain size (0-8 mm), the material was therefore then adjusted in the jaw crusher.
Due to the character of the material it was used as a substitution of a siliceous sand of grain size 0,5-4 mm.
The foundry sand was used as a substitution of a siliceous sand of the grain size 0-0,5 mm.
The testing recipes were named after the used secondary raw material with the number which represents the rate of substitution of the binder or the filler.

Tensile specimen sampling location(a)consecutive solidification(b)simultaneous solidification For the purpose to ensure the accury of test results for mechanical properties, each same part (as the number emphasis marked in Fig.3) manufactured four samples.
The stress concentrated at the grain boundaries, causing brittle primary Si and eutectic Si particles broken, followed by cracks grew along the grain boundaries until the specimens fracture.
The eutectic silicon particles inside the stress frame casting transformed into spherical shape from needle and laths morphology, the grain boundary becomed more dense and more tiny.
Adhering to the fracture surface after breakage, both the primary and eutectic silicon particles were hard and brittle phase, a number of dimple pits distributed on the surface of cracks, enhancing the mechanical properties of the castings.
The STL format model was subdivised with the uniform mesh, the size of grid was setted to 2 millimeter, the gridding number of the gating system after subdivision was 3526870, 0.1 was used as the scale proportion.

Chart 1 Main Attack Types and Defense Approaches of WSN Protocol Stack Attack Types Means of Defense physical layer signal-jamming frequency spread, frequency jump, setting priorities of messaging, switching of communication channel(e.g. light, ultrared rays), delay-tolerant eavesdropping encryption of sensitive information, message authentication code, end-to-end authentication mechanism tampering add message authentication code,  integrity detection, intrusion detection, key update physical damage concealment and disguise, flow analysis control capture&cloning intrusion detection, key update link layer collision intrusion detection,  check code,  time division multiplex or frequency division resource exhaustion limit number and times of messaging, monitoring of the abnormal behavior of  neighbor nodes network layer route spoofing &replay intrusion detection, increase  count value or time stamp, digital signature sybil attack polynomial pool-based key management, node registered, code
If this protocol is applied, there will be no need to use the directive antenna and the fine-grained synchronous clock for detecting the black hole attack, which will reduce hardware cost of the codes greatly.
After that, the jumping number with distance will be compared, if the largest possible distance of that number is still shorter than the real distance between the two nodes, it will be regarded that wormholes exist in the route.
There is no need to install the directive antenna and the fine-grained synchronous clock and its hardware cost is low.
Because of that, on one hand, the node can not respond to connection requests of the normal nodes because the nodes reach the set maximum connection number; on the other hand, memory of the node will be exhausted for maintenance of large quantity of false connection.

The above-mentioned prediction model for non-equidistant time sequence will be applied to them and the prediction accuracy will be discussed. 3.1 The application to rock creep fracture test At a room temperature of about 20 o C, three-point bending creep fracture tests were performed on a group of specimens fabricated from red fine-grained sandstone material, which is regarded as homogeneous and isotropic and meets Kelvin-Model.
The time intervals of sustained loading and other corresponding data for red sandstone specimens used in three point bending test with creep conditions Ordinal number KI (kN ·m− 3 2 ) ti (kN ·m− 3 2 ) -1 X (0) (ti) (day) X (1) (ti ) (day ·kN ·m− 3 2 ) 1 2 3 4 5 230 215 206 196 187 0.004348 0.004651 0.004854 0.005102 0.005348 2.6 10.3 50.4 138.0 unknown 2.6 2.6031 2.6134 2.6476 unknown Fig.1 Illustration of the cuboid specimens for three point bending test Notes: The type of specimens used in the test is specimen B.
i = Ordinal number KI = Stress intensity factor ti = 1/KI X(0)(ti) = Time interval of sustained loading for rock specimen under three point bending test, which had led to crack initiation and propagation under creep conditions.
By using it, the time for crack initiation and propagation of red fine-grained sandstone material under a creep condition can be forecasted and predicted.
The creep fracture time of the gypsum material under different creep pressure stress Serial number 1 2 3 4 5 Creep pressure stress (σi) (kgf/cm2) 41 38 32 29 26 Independent variable (ti = -σi) (kgf/cm2) -41 -38 -32 -29 -26 Dependent variable (X (0) (ti)) (day) 1.6 5.4 10.6 14 18.0 First-order weighted sum X (1) (ti) (kgf/cm2·day) 1.6 17.8 81.4 128.4 Simulated or predicted X (1)(ti) (kgf/cm2·day) 1.6 19.6 74.6 115.6 169.5 Data for modeling Predicted result From Table 2 it can be concluded that the predicted X ^ (0) (t5) is 18.0 day, but the tested X (0) (t5) is 19.5 day.

Farming as its main agriculture and grain production heading the list, Huanggang City is the important manufacturing base of grain, cotton, edible oil, domestic animal and hog in Hubei Province, which outputs are 3011.4, 82.9, 514.5 thousand tons, and 819.4, 4796.6 thousand heads. respectively, which occupy the top three in Hubei province[2].
Cobb-Douglas production function is suitable for description agricultural production, adopting double logarithmic form as follow: lnYt = B1 + B2lnX2t + B3lnX3t + B4lnX4t + B5lnX5t + B6lnX6t + B7lnX7t + B8lnX8t + ut, (1) in which the subscript t represents time, i.e. year, Bi (i=1, 2, …, 8) are the intercept and partial slope coefficients, Y is the gross output value of agriculture calculated on the price in 1995, X2 is the total power of agricultural machinery(10 million watt), X3 is the consumption of chemical fertilizer(10 thousand ton), X4, X5 and X6 are the numbers of big animal, hog and sheep in stock, respectively(10 thousand head), X7 is the planting area(thousand hectare), X8 is the reforestation area(hundred hectare), and u is the error term.
Big animals in stock elasticity of gross output value is -0.869, which shows that the number of big animal increasing 1% could make gross output value decrease 0.869% averagely.
In conclusion, the gross output value of agriculture is positively related to total power of agricultural machinery, consumption of chemical fertilizer, hogs in stock and sheep in stock, and is negatively related to the number of big animal and planting area, which shows that agricultural development of Huanggang City still follows the path of high-carbon and oil agriculture in the past 17 years.
The number of big animals in stock and planting area have significant negative effects on gross output value of agriculture, and their contribution rates are negative, too.

The purity of iron oxides for monoferrites is a parameter that must be rigorously controlled and observed, this is due to the fact that a number of secondary elements can act negatively in the sintering process.
Its fine distribution ensures an increase of reactivity due to the free valences of the ions on the particles surface and to the fact that the number of contact points between the analyzed substances is much higher than in coarse-grained materials.
The large number of contact points has direct implications in the sense that the process is more energetic.
Conclusions The research involved a large number of parameters that influenced the pyrosynthesis reaction, as follows: the quality of the initial materials (purity and particle size of iron oxides) and working conditions determined by the specifics of the work equipment (dry and wet homogenization, working protective atmosphere) Taking into account Fig. 8 and table 1, some conclusions can be drawn: - The mixture for monoferrite, which contains large hematite powders, recorded the highest pyrosynthesis temperature of 860oC.
Zheng, Effect of Powder Grain Size on Microstructure and Magnetic Properties of Hexagonal Barium Ferrite Ceramic, Journal of Electronic Materials, Vol. 47, No. 7, (2018) pp. 4085-4089