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The implication is that the grain boundary phase can be another controllable factor against contact damage and strength degradation even though it is not critical relative to the effect of grain morphology.
A mechanical contact is one of the important characterizations to consider the lifetime of these components [3].
While Si3N4 ceramics exhibit excellent thermal and mechanical properties at both room temperature and high temperature, the critical drawback is low reliability due to inferior fracture toughness rather than a commercial metal.
Many studies demonstrated that the mechanical properties of Si3N4 are influenced by a heterogeneous microstructure with weak grain boundary phases [9,10].
It is apparent that changing of grain boundary composition greatly affects contact damage and crack initiation load.

Because the fibers can orient during injection molding process and the orientation has close relationship with plastics parts’ mechanical properties, there are many factors that can affect fiber orientation such as matrix materials properties, reinforced fiber properties, processing parameters and mold geometry so forth [1-3].
In this study, the seven parameters Cross-WLF viscosity model in analysis of injection molding simulation is defined in equation (4): (4) where and are defined in equation (5): (5) where are material physical properties constant,,,and represent viscosity, shear rate, temperature and pressure individually.
Fig.4 The fiber orientation distribution curves and probe points of three different schemes (a) 1st scheme; (b) 2nd scheme; (c) 3rd scheme (a) (b) (c) Deformation of injection molded parts is inevitable, but for the parts that are molded with short glass fiber reinforced polymer matrix composites, there are three factors that can induce deformation, which are shrinkage, cooling and orientation factors, and the three factors lead to shrinkage deflection, cooling deflection and orientation deflection respectively.
Thus, it can be inferred that orientation deflection plays an important role in molded parts deformation of short fiber reinforced polymer matrix composites and the factor of orientation isn’t neglected.
Polymer, Vol.46, No.17, pp6719-6725, 2005 [4]Wang H.T., Yao Z.H.. large scale analysis of mechanical properties in 3D fiber-reinforced composites using a new fast multipole boundary element method[C].

Poor mechanical properties of both HA and CHA limit their uses in the loading sites [6].
Apart from the thermodynamic considerations, solid reaction can be affected by the kinetics factors.
Temperature is one of the important external conditions to affect the solid-reaction rate.
The rate constant K is given by the equation（1）for the chemical reaction, （1） Where is the activation energy for chemical reaction, A is factor related to the particle activation.
The diffusion factor D is given by the following equation（2）for the diffusion reaction, （2） Where Q is the activation energy for diffusion reaction, D0 is frequency factor.

To explore between beam just rigid, articulated, semi-rigid and so on the different connection for the effect on the properties of the stress of the structure, and at the same time, considering the structure model is a big gap between the height (maximum height 6m tall, with a minimum of 3m), the structure is more soft, at the same time SAP2000 can use releasing node part constraint to simulate the semi-rigid nodes, For the following three different node rotational stiffness for structural model finite element analysis: are 2×104kN·m/ rad for semi rigid connection 1, 1×104kN ·m/ rad for semi rigid connection 2, 5×103kN·m/ rad 3 for the semi rigid connection，coupled with rigid connection and articulated, this paper used a total of five different beam-column joint connection manner structure stress performance analysis. 3 Finite element analysis results 3.1 Dynamic analysis Table 1 Effect of different connection modes of the model
We can see that, with the increase of the layer number, side column X to sway in the 5 kinds of node stiffness under both showed a trend of increase, There is no obvious structure stiffness weak place; Vertex X to sway with beam-column joints stiffness is decreased. 3.3 Dynamic time history analysis Response spectrum depends mainly on earthquake acceleration the most strong records , but previous earthquake damage phenomenon shows that the duration is also affecting the structure damage degree of important factors.
In accordance with the building site soil remarkable cycle, seismic wave frequency spectrum characteristics, the structure and its own dynamic factors, select the United States elvis and cent and (time interval 0.02s, total time for 30s, wave is 314.7cm/s2) structure response and displacement analysis.
After the proposal analysis study, will be other factors into consideration at the same time.
Consider beam-column semi-rigid connection mega frame mechanical performance study [J].

Phosphorus, fluorine impurities formed into calcium-phosphate and calcium-fluoride in process of gypsum conversion reaction which is dissolvable and covered the surface of crystal, and severely hampered the development of gypsum crystal and made the mechanical properties of high-strength gypsum deeply affected.
Most of the research considered that synthesizes each kind of factors; the Lime Neutralization is the best of the traditional methods [4].
The principle of the Water-Washing was clean up most of the soluble impurities which would affect the quality of the phosphorus gypsum in the phosphogypsum by adding water in and pout it out again and again.
So synthesizes each kind of factors, the processing efficiency of Lavation is better than the all kinds of traditional methods.
Synthesizes each kind of factors, the lavation was better than the traditional methods.

In order to control the properties of the hybrid components, four different tool concepts for the prepreg press technology have been developed and tested.
The semi-finished component with carbon fibre prepregs displays highly diverse properties and thus requires a suitable tool and process design.
In order to validate the linear dependency of the compound properties on the properties of the compound's individual components as a function of the fibre volume content, tests using cured CFRP specimens were conducted for various fibre orientations.
The mechanical part is further split into a volumetric and a deviatoric part.
∂p∂t=kAexp-EARTpα1-pn (11) Some of the parameters used for simulation, like the curing shrinkage αcur and the factors for the prony series G(s,t) and K(s,t), were estimated, and additional experiments are currently in progress to verify them.

There are three main factors of affecting ensilage.
Main Parameters Affecting the Quality of Pasture Ensilage Moisture Content and Density of Pasture.
So the main factors influencing the ensilage include the following three aspects.
Second, its property resisted puncture, tear and ultraviolet rays is very good.
Fourthly, it has good gas resistance property, namely, its permeability resisted to oxygen is good.

To enhance the quality of H-beams, factors such as the shape of rolling grooves, flow characteristics of the material, friction coefficients between the roller and work-piece and the thermal field of work-piece, must be considered.
Microstructure and Property on the Cross-section, Web Fracture and Wave Microstructure and Property The material of workpiece is Q235B (Carbon structural steel).
And the residual compressive stress affected regions along the flange thickness direction will be expanded.
China Mechanical Engineering, 2007.7, 14(18):1747-1751
[2] ZHU Guoming, KANG Yonglin, CHEN Wei, MA Guangting. 3D Thermal Mechanical Coupled Elasto-plastic Finite Element Analysis in the Whole Rolling Process of H-beam.

RSM coupled with the central composite design was used to optimize the mechanical properties of composites [10].
(11) Here, represents the quadratic effect of the ith factor and represents the cross product effect, or interaction effect, between the ith and jth factors.
Fig.1 shows the uniform Latin square method designed the rational experimental samples with two factors, in which, there are 11 points sampling in the spatial arrangement.
The acoustic properties of the air are: density ρ=1.225 kg/m3; the speed of sound c=343 m/s; Sound power reference value W0=1×10-12 Watt.
[10] K L Low, S H Tan, S H S Zein, D S Mcphail and et al.Optimization of the mechanical properties of calcium phosphate/multi-walled carbon nanotubes/bovine serum albumin composites using response surface methodology.

The accuracy of the welding robot is a critical factor affects the welding quality; the method to improve its kinematic accuracy is position-pose error compensation which is based on the analysis of its position-pose error [3].
The key factor for analysis of position-pose error is to establish the position-pose error model.
Error analysis of welding robot There are lots of factors influence the robot position-pose accuracy, including: (1) the error of the structure parameters and the movement variables of the robot, there appears deviation between the actual parameters(, , ,) and its nominal value because of the error of the manufacturing and assembling process, as a result cause the error of the robot position-pose [4-5]. (2) Environmental factors, such as the temperature change of the work environment and long time wear of the robot will lead the length of the connecting arms size to produce error, and cause robot position-pose error.(3) the joint error (including the inherent error and the joint angle error which causes by the wear of the kinematic pair), the position transducer error, the control system's error and so on.
Position error caused by the sensor and reducer factors.
The simulation result shows that the error of a single direction is between ± 0.8mm, the total position error caused by the sensor and reducer factors is concentrated in the range of 1mm, which meet the requirements of welding technology.