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In general, the main factors affecting concrete cracks comprise concrete temperature difference, autogenous volume shrinkage, thermal expansion coefficient, elastic modulus, creep of concrete, bond to concrete from foundation or constraints to new concrete from old concrete, pouring block length and thickness, ultimate elongation, surface heat performance, conservation measures and structural conditions and parting block construction stratification, etc., which are related to time.
Cracks is not a simple problem, but a comprehensive topic consist of structural design, thermal and mechanical properties of materials, method of construction and process as well as engineering control measures.
There are fluctuations in the temperature rising process of point 10 which was affected by air temperature.
Maximum temperature of this section difference between inside and outside (3.5 days) is about 6.93oC, less than case 1 which was around 6.07oC The results of feature point 10th on the surface also has a similar affect.

Study on the Cooling System of super-capacitors for Hybrid Electric Vehicle Zhengpeng Xia1,a, Chenquan Zhou1,b, Dan Shen1,c , Hongjun Ni1,d, Yinnan Yuan1,e, Liao Ping1,f 1School of Mechanical Engineering, Nantong University, Nantong, 226019 axiazhengpeng246@163.com, bteyaxiu@126.com, ccooldan_1988@126.com, dhjni910@yahoo.com.cn, eyuanyn@ntu.edu.cn, fliao.p@ntu.edu.cn Key words: hybrid electric vehicle; super-capacitors; cooling system; Star CCM+; Abstract.
Introduction Super-capacitor as one of the important sources of energy of hybrid electric vehicle (HEV), its performance would directly affect the performance and security of the HEV.
In all the external factors that influencing the performances of super-capacitor, the influent degree of temperature on the performance was the most.
If the super-capacitor package couldn’t cool timely, the difference of temperature is bound to occur around the single capacitance, which causes the performance of the capacitor package inconsistencies, thus affecting the service life of the capacitor package, even appear security risks[2].
The mainly reason was at the low temperature, electrolyte conductivity was small, the migration resistance increased, made the dynamic properties of lithium ion reduce, leaded to the discharge capacity of the capacitor decrease; (3) Under the condition of high temperature, the discharge energy of capacitor would increase, but when the temperature was higher than 55℃, the discharge energy and efficiency of the capacitors would decrease.

A Feasible Speed Profile Model for Automatic Train Protection System Guodong Teng 1, a, Shunding Hu2, b * 1Hangzhou Institute of Service Engineering, Hangzhou Normal University, Hangzhou, 311121, China 2 United Mechanical & Electrical Co.
By reference to this model, we present a feasible speed model which is simplified as three phases, and consider practical factors, such as the maximum acceleration at each phase, the worst gradient, traction and braking force of the train, etc.
To simplify the model, it is assumed that the train continues to decelerate with the maximum braking force, which will not affect the safety of system.
To the convenience of calculation, here we adopt the worst gradient, which will not affect the safety of system. 3) : The time of B phase, which is a time configuration parameter of train
As future work, more practical factors will be considered, and the practical factors may affect the safety of our speed profile model.

However, the developed RC foundation is so new that the mechanical properties, especially the stress state, are less researched and reported.
According to Saint-Venant principle, the role, which the ground at the bottom of the model will not affect the deformation of the wind driven generator will be considered, therefore, the immovably confined boundary at the bottom surface of the model and the normal direction constraint boundary at the circumferential direction side of the model are taken for the FEA model.
Table 1 The load standard value at the top of the foundation steel stub (without safety factor of 1.35) Name of project situation Fx (kN) Fz (kN) Fy (kN) Mx (kN·m) Mz (kN·m) My (kN·m) Normal operating loads 350.6 -111.8 1969 8263 20530 -47 Extreme loading 84.22 575.5 1891 -31391 1995 170.3 According to China RC Foundation Design Code, the limit state design method is applied in the paper and the extreme load case is used for the design and calculation.
The dimension and material properties are the same with the above developed one, and the same load (ultimate load) is applied on the two kinds of foundations, to compare the results of the stress and displacement and observe the difference between two kinds of foundations and the superiority of the anchor foundation.
(3) This new type rock anchor foundation is safe and reliable by compare with the mechanical properties of the non-anchor foundation, and the application of the rock anchor RC foundation of the wind driven generator has the superiority of resisting overturning.

Preliminary in situ diagnostic inspections were carried out for evaluating the environment conditions of the timber structures, evidencing the presence on the members of natural defects, damage and decay situations and, at the same time, characterizing the elements as respect to the wooden species and mechanical properties by means of visual grading (UNI 11118 and UNI 11119, 2004).
Furthermore, members are generally classified as belonging to class III, to which the worse mechanical properties correspond.
Concerning the mechanical characterization, for the structural models related to the erection phases of the structure the material is modelled as “new timber”, assuming the mechanical properties according to UNI 11035-2 (2003) standard; besides, considering that the timber could be affected by working lacks and degradation, the material is also modelled as “ancient timber” in the phases related to the present state, according to UNI 11119.
The assumed mechanical properties are summarized in Table 1, where g is a mean value of wood density, E0 and E90 are the longitudinal and transversal moduli of elasticity, n0 and n90 are, respectively, the Poisson’s ratio in longitudinal and transverse direction according to technical literature [6], G0,90 and G90 are the shear moduli in the parallel-perpendicular to grain planes and in transverse planes, respectively.
Mechanical properties of “new timber” and “ancient timber”.

Modular design of the seeker in 3D environment We can see from the first section that, as the core of the DDD, domain model is the key factor of the success of DDD.
Different types of seeker have certain requirements for its structure, thereby affecting the size and the weight of the seeker.
The interface consists of mechanical interfaces and electrical interfaces.
The task is to do simulation analysis on the assembly of the seeker and its corresponding parts and analysis their dynamic properties, electrical properties and optical properties, to see whether they met the indicator parameters required.
Based on the thought of MBD, we offer subsidiary information to the 3D model of the product through integrating the design process, design knowledge, data, method and other factors and embedding Autovue product of Oracle Corporation to the system to markup model and documentation.

Compared with other hard tissue substitutes, CPC has the properties of good biocompatibility, convenient operation, stable capability and conducting the formation of new bone with the adsorption of the material, which make it possible to solve the longstanding problems of bone repairs.
The mechanism of the hydration process, the mechanical properties, physicochemical properties and biocompatibility have been explored in details [5-7] .
Porous Calcium Phosphate Cement Most of the hydration production of current available calcium phosphate cement is dense, which not only affects the biodegradability, but influence the formation of blood vessel, the growth of cells and surrounding tissue into the material, the controlled-release of the bioactive substance, such as growth factor, drug etc.
The formation of networks and the development of the microstructure in the slurry affect not only its flow and injection, and consequently its workability, but also the mechanical properties of the cement after hardening.
Previous studies have showed that sodium alginate could improve the water-resistant property of CPC.

However, variable fill hydrokinetic coupling has disadvantages of low efficiency, huge waste heat and poor control performance; variable frequency control with higher voltage and power is limited to its behaviors on explosion-proof, heat rejection and harmonic wave pollution; high-price CST system, combined with reducer, is affected by each other, and its maintenance is difficult, though its higher accuracy of regulating speed; hydro-viscous soft starter is independent on reducer but a little expensive.
Fig. 1 Regulating-voltage mechanical properties Fig. 2 Curves of starting with full voltage of three-phase asynchronous motors and ordinary hydraulic coupling Starting with full voltage and ordinary hydraulic coupling The starting mode with full voltage and ordinary hydraulic coupling can start belt conveyors carrying loads and fully use the maximum output torque of a motor.
Fig. 3 Regulating voltage principle of Fig. 4 Curves of starting with reduced fuzzy self-adaptive PID control voltage and ordinary hydraulic coupling Due to viscoelastic belt, frequent surge loads and complex interfering factors, the relationship between speed of a belt conveyor and the voltage of a motor is uncertain.
Starting process Fig. 4 illustrates the starting characteristics of three-phase asynchronous motors’ reduced voltage starting and ordinary hydraulic coupling cooperatively applied to the conveyor belt, where, curves 1, 2, 3 respectively represent three-phase asynchronous motors’ mechanical properties under different input voltage; curvesⅠ , Ⅱ , Ⅲ respectively describe the input features of ordinary hydraulic coupling with different transmission ratio.
Deng, Mechanical and electric drive control, fourth ed., Huazhong University of Science and Technology Press, Wuhan, 2000, pp.62

The importance of Solder Joint Reliability (SJR) became more emphasized in recent years as a result of two factors: (1) the shift of the semiconductor industry to lead-free solders; (2) the emergence of fine-pitched surface-mount packages that employ hundreds of solder joints for electrical connection.
The material properties of flip chip package were shown in Table 1.
Table 1 Material properties of flip chip package Material Elastic modulus (GPa) Poisson ratio CTE (ppm/) Thermal conductivity () Silicon 131 0.30 2.8 150 Flex substrate 6 0.36 20 393 PCB (FR4) 22 0.28 18 13 Solder (SnAg) E=36.85-0.18×T () 0.4 21.85+0.02039T 51 A non-linear finite element model was made to study the reliability of the typical flip chip assembly, as shown in Fig. 2(a).
For the rigid PCB substrate, the mechanical situation is the same, but because rigid substrate is much stiffer than solder, thus solder joint is deformed instead of rigid substrate.
The selection of different substrate materials could affect solder joint thermal fatigue life significantly.

In specific applications, depending on the application, the material properties can be linear or nonlinear.
Considering these factors, we do the following constraint processing: corresponding coupling processing of the contact constraint is done at the hinged position (hinged hole) of the two main beam and side beams, which is coupled in the FX direction.
Gravity Gravity is the distributed force; density has been added to its material properties, in ANSYS, only gravity acceleration values need to be given.
In addition, Reverse factors are considered as coefficient in the calculation of tower crane design, soin this paper we do not do the research about torsion of crane. 2.
BeiJing : Mechanical Industry Press .2003：1-183