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The occurrence of the secondary γ′ precipitation resulted from the complex interaction of multiple thermodynamic and kinetic factors in the γ′ nucleation and the diffusion rate of γ′ forming elements.
Due to its excellent high temperature mechanical property, superior resistance against hot corrosion and oxidation at elevated temperature, it is widely used for components in the hot sections of gas turbines for aero-engines.
The excellent high temperature mechanical property is mainly acquired by a large amount of coherent γ′ precipitates from the γ matrix in Ni-based single crystal superalloy [2–4].
In order to explain the above results of the primary γ′ size changes, the thermodynamic and kinetic factors need to be considered for the formation of the primary γ′ precipitates.
Based on these discussions, the secondary γ′ precipitates result from the complex interaction of multiple thermodynamic and kinetic factors such as driving force for the γ′ nucleation (critical nucleation barrier, ΔG*), the γ′ nucleation sites (related to the nucleation rate) and the diffusion rate of γ′ forming elements.

Mechanical properties, the early high strength, high toughness and volume stability, in bad make with the conditions of long service life, high strength, high liquidity and good durability.
The current domestic application good as above its action the sea with concrete bridge, the design life in 100, the use of "offshore mix of high performance Soil "of fly ash, is the waste decayed for magical, become special content And material, make the sea work both high strength and durability of concrete, corrosion properties.
The high performance concrete bridge engineering application is the advantage of (1) spans longer; (2) the main girder spacing more; (3) Component thinner; (4) durability strengthened; (5) to strengthen the mechanical properties.
Under the influence of the vehicle load and other factors, there were more problems raised, such as the concrete of connection steel plate surface spelled, the connection steel plate corrosion and other issues, seriously even the weld cracking of connection steel plate, and the diaphragms could not play normal work performance, Or even a single beam under load [1].
Guo. (2007) Experiment on shear property of new and old concrete bonding with planting steel.

The shape of these nanoparticles aggregates are of great significance for the mechanical material properties and in consequence, knowing the percentage of aggregates of each shape within of a specific group of shapes can give an idea of the final properties of the material.
Introduction The final application of materials, like the study case of rubber blends but applicable to many materials, is strongly dependent on their properties and on the reinforcement particles that constitute the material.
At the same time, the morphology of these nano-particles affects the final properties, so that a good characterization of the morphology is really helpful [1, 2,3].
Classification technique Parameters Grid of values Selected values BCT cp (complexity parameter): Any split that does not decrease the overall lack of fit by a factor of cp is not attempted 0:2 0 C50 trials: number of boosting iterations 1:100 90 model: tree model or decomposed into a rule-based model tree, rules rules winnow: feature selector yes, no no C45 C: confidence threshold 0:1 0.21 BCART none RF mtry: number of variables randomly sampled as candidates at each split 1:21 1 Figure 1 Variation of the accuracy on the selected classification model during the training process related with the parameters of the algorithm (a.

The Finite Element Analysis of the Wind Turbines's rotary support Hongliang Hu, Ruijie Wang, Chunling Meng, Guofeng Li (Beijing Technology And Business University, School of Material and Mechanical Engineering, Beijing, 100048, China) Key words: wind turbines; the rotary support; finite element analysis Abstract.
The motor part of the wind turbine yaw system are all installed in the rotary support which bears the actuator of yaw system, the front part of the wind turbine’s (including the fan spindle, generator, hub, blades, etc.) gravity and loads and pass these to the tower, so the performance of the rotary support directly affects the operation of wind turbines.
As the relatively complex force and structure, traditional algorithms can not meet the required precision and not make theoretical analysis, requiring to apply the finite element analysis to analyze its structural rigidity, natural frequency and other properties, the results for the wind turbine rotation support provide a theoretical basis for further design, finalization of the program[1-2].
Fig.4 The stress distribution and stress table under Fz(min) Conditions The material yield limit of the rotary support is 215MPa.According to the mechanical strength requirements from fan specifications[6-7], calculations take safety factor n = 1.1, so the rotation support’s allowable stress is: The maximum stress in all conditions is 52.3MPa and the maximum work stress is less than the maximum allowable stress, so the rotary support meet the static strength safety requirements.
Mechanical vibration[M].Beijing: Tsinghua University Press,2009

Effects of axial spindle vibration on surface generation in ultra-precision diamond turning Shao Jian Zhang1, 2, a * and Suet To2, b 1Research Institute of Mechanical Manufacturing Engineering, School of Mechatronics Engineering, Nanchang University, Nanchang, Jiangxi, PR China 2State Key Laboratory in Ultra-precision Machining Technology, Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, PR China aS.J.Zhang@connect.polyu.hk, bSandy.To@polyu.edu.hk Keywords: Model, Spindle vibration, Surface generation, Ultra-precision diamond turning Abstract.
The general factors include machine tool [2], cutting conditions [3], tool geometry [3], cutting heat [4, 5], material property [6], chip formation [7], tool wear [8, 9], vibration [10-12] etc.
In UPDT, ASP plays an import role in the factors influencing surface generation.
Lee, Study of factors affecting the surface quality in ultra-precision diamond turning, Mater.

(2) Confirmed the probability density function of random factors, and supposed all of the factors were mutually independent
(3) Each random factors created random numbers in the interval of [0,1] (1) Where is the number of variables, .
It is the most typical DOE with reasonably uniform sampling point distribution property.
Monte Carlo sampling points （a） （b） （c） （d） It can be seen from Figure 4(a) that acceleration in proportion to vertical velocity, and it is less affected by horizontal velocity.
As can be seen from the Figure 4(c), when the horizontal velocity is low, the acceleration is less affected by gradient.

By means of “micro-peak and soft/hard plane” contact model given in the present work, physical definition and influence factors of tC1and tC2 were discussed in detailed.
By means of the simplified contact model of micro-peak and soft/hard plane presented in the following section, the influence factors of two inflexions are demonstrated in detailed, and then some principles of optimized designation for the complicated triblogical system are given to make soft layer on the hard substrate more economical and longevous.
Obviously, the value of Hm is related to not only the mechanical properties of soft layer, the coarseness of friction parts but also the thickness of the soft layer.
(8) As shown in Eq.(7), the values of tC2 are determined by the applied load, the surface morphologies of the mutual friction parts, and the mechanical characteristic of soft layer.
By means of “micro-peak and soft/hard plane” contact model, those are pointed out that the value of tC1 chiefly depend on surface morphology of substrate and counterpart, whereas the value of tC2 is also affected by the applied load and layer characteristic.

The probable wind conditions under service phase as well as the accurate evaluation on the corresponding results are the crucial factors that should be taken into consideration during membrane structure design.
Structural control, developed in the 1970s, is a new design method to improve the mechanical behavior of the structure by control device in view of classical or modern control theory.
SMA is recognized as the most promising smart material in the structure vibration control for its special shape memory effect, unique super elasticity, high damping, better restorable ability and good fatigue properties.
For example, the project we investigated is located at class B landforms, the highest point is 25m, the reference wind pressure is 0.50KN/m2, the pressure coefficient of height variation is 1.335, the coefficient of wind-induced vibration is 1.9 [3], the shape factor of wind load is 0.4 [4]; according to load code for the design of building structures [5], the static pressure is 507.3 N/m2.
The rigidity of SMA spring is a function of marten site fraction, and the percent content is affected by temperature and external load.

The forward velocity of the cavity is the most important factor which has a pivotal influence for the degree of orientation and residual stress of product [1].
It's RIM module can be used here through changing some process conditions, for example, the maximum injection pressure, material's properties and so on[4].
Fig.8 The expected pressure curve Conclusions In order to keep the forward velocity as smoothly as possible, a detailed study of the most important pressure parameters that affect the quality of the final VC parts, namely, the pressure values, is performed to assure constant forward velocity in the present investigation.
Using this CAE model and BP-NN analysis techniques, together with MATLAB software, the expected pressure curve, the factors that are most significant for serving the filling control system can be achieved.
Acknowledgements This work is supported by Innovation Foundation of SHU (A.10-0109-08-010), Shanghai Science Foundation for the Excellent Youth Scholars (B.37-0109-08-004), and the fund of Shanghai Key Laboratory of Mechanical Automation and Robotics (D.10-0109-09-006).

Therefore, to determine the durability of the rubber polymer (rubber polymeric concrete), taking into account the temperature factor is a very up to date problem.
(3) where: s, Т, t - strength, MPa; temperature, 0К; time to destruction, sec, respectively; R – universal gas constant; - force, structural and mechanical factors; U0 -energy of activation of destruction; Tm - limiting temperature; tm – minimum durability at any tension or without it.
The change in the material constants , and is significantly affected by the introduction of the composite plasticizers, antioxidants, manufacturing method and structure of the composite structure.
Shutilin, Handbook of elastomer properties, Voronezh State Technological Academy publisher, Voronezh, 2003