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Introduction The phenomenon of crystallization following after pouring molten metal into the mould, determines the shape of the primary casting (ingot) structure, which significantly affects on its usable properties.
According to presented data in papers [3, 4], this type of structure gives low mechanical properties of castings and mainly is unfavourable for the plastic forming of continuous and semi-continuous ingots, because causing forces extrusion rate reduction and during the ingot rolling delamination of external layers can occur.
This structure can be eliminated by controlling the heat removal rate from the casting, realizing inoculation [3÷9], which consists in the introduction of additives to liquid metal and/or influence of external factors for example infra- and ultrasonic vibrations or electromagnetic field [4, 10÷13].
In case of this inoculation with use of external factor in form of electromagnetic field, which creates forced movement of liquid metal in mould in time of its solidification, the refinement of structure mainly results from thermal and mechanical erosion of crystallization front.

Several factors contribute to the presence of hydrogen in the working conditions of these components: the use of long-life lubricants with certain additives contributing to hydrogen generation; the moisture entering the bearing; the salty environment that increases the probability of hydrogen penetration.
The following mechanical properties were considered for the rod and the balls: E (Young´s modulus) = 206 GPa, n (Poisson coefficient) = 0.3 and sY (yield stress) = 2065 MPa.
The first driving force for hydrogen diffusion, the gradient of equivalent plastic strain, is negative and only affects the plastic strain ring (covering a maximum depth from rod surface around 340 mm) near the rod surface shown in Fig. 2b.

The terminal sliding mode (TSMC) control was developed by introducing the nonlinear item into the sliding mode, which offers some superior properties such as fast, finite time convergence and better tracking precision [9].
Parameter ，，and affect the arriving time, so appropriate value must be selected to ensure the converging speed.
The classical PID control is employed in the acceleration feedback controller, as shown in figure 1; the control law is defined as: (11) where is integral factor of the controller, is proportional factor of the controller, is differential factor of the controller, and they are positive real numbers.
Conclusions Opto-electronic stabilized platform is a kind of servo system with uncertainties and disturbances (such as nonlinear friction factors).
Liu : Decomposition-based friction compensation of mechanical systems[J].

Because the key factors of the dynamic performance of the machine tool are related to the characteristics of the conjoint interface, the feeding system as an important part of the machine tool, which contains typical rolling conjoint interface and fixed conjoint interface, so in order to study the dynamic performance of machine tool better, the modal analysis is carried out on the feeding system.
Introduction Research shows that: 30% ~ 50% of the static stiffness depends on the rigidity of the joint, more than 90% of the machine damping and 60% of the vibration problems of the machine tool come from the joint, so the dynamic characteristic parameters of the joint are the key factors that affect the dynamic performance of the machine tool [1].
So the finite element simulation analysis of the mechanical structures with different conjoint interface characteristics can be carried out.
Zhang, Dynamic Characteristic Analysis of Ball Screw Feed System Based on Stiffness Characteristic of Mechanical Joints.
Cai, Identification method of dynamic properties of bolted joints.

(iii)Specify boundary region Designing the model name and type to each region for the model prepare the physical properties, boundary and initial conditions of subsequent given model.
It is more reasonable of using this approach in the calculation of the flow field mechanical blade.
The grid scale amplification from the inside out, factor generally taken to be 1.1 to 1.2.
The grid is rather poor at the intersection; it can affect the calculation accuracy.
If it is a single-channel’s computational domain, then the cycle boundary can be drawn a border area, but it does not affect the periodic boundary grid.

The axial compression ratio has greatly influence on the joint mechanical properties [2-5].
Using finite element method to analysis and discussion the mechanical properties this two kinds of joints, such as the bearing capacity, energy dissipation capacity and stiffness of joint.
Table 1 Geometry size of sections Name of components Size of section /mm Wall thickness /mm steel cylindrical column 120×120 2.5 steel cylindrical beam 100×100 2.0 C steel beam 180×60 2.0 Hysteric property analyses.
Especially for welded joints; the axial compression ratio is an important factor that affect the seismic performance of joints, the higher of axial compression ratio, the poor of ductility.
But the yield platform of QJ joint is much shorter than the GQJ joint; As the increasing of axial compression ratio, the yield load and ultimate load decreased significantly, it showed that the axial compression ratio had great effect to bearing capacity of joints, especially to QJ. (2) Before the point of elastic limit, deformation of the joints basically present elastic properties; As the increasing of load, the skeleton curve began to bend, enter the elastic-plastic deformation stage, the load increaseing lag behind the deformation, the stiffness of specimen reduce faster.

The chemical and physical properties of cement are provided in Table 1.
Table 3 represents the chemical and physical properties of the superplasticizer.
Monteiro, Concrete microstructure properties and materials.
Pielert, Significance of Tests and Properties of Concrete and Concrete-Making Materials.
Kaplan, Flexural and Compressive Strength of Concrete as Affected by the Properties of Coarse Aggregate.

The transducer is designed such that it is not affected by chirping and light loss to enhance the performance of the sensors.
Introduction Sensory information of human skin for feeling materials and determining many of their physical properties is provided by sensors in the skin.
First, there are two major factors that must be considered upon designing the transducer of FBG force sensors.
The other factor is chirping, which causes distortion of the Bragg signal.
This non-linear relation appears to be caused by the non-linear material property of the transducer.

A Calculation Method for the Coupling of Temperature and Concentration During Inconel 718 Alloy Solidification Ao Xiaohuia, Xia Huanxiongb*, Liu Jianhuac, He Qiyangd, Lin Shengxiange School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China axhao@bit.edu.cn, bhxia@bit.edu.cn, cjeffliu@bit.edu.cn, dhe_qiyang@163.com, e3120195209@bit.edu.cn Keywords: Temperature gradient; Cooling rate; Concentration; Kinetic undercooling Abstract.
Introduction Temperature and concentration are two important factors that affect the nucleation and growth of grains, and the different microstructure can be obtained by changing them.
The material properties used in our simulations are listed in Table 1.
Table 1 Physical properties of Inconel 718. [7] Property and symbol Value Liquidus temperature Tl [K] 1678 Solidus temperature Ts [K] 1643 Initial solute concentration C0 [wt. %] 5.0 Liquidus slope ml [K/wt. %] -10.5 Partition coefficient k0 0.48 Gibbs-Thomson coefficient Г [K∙ m] 3.65×10–7 Liquid diffusion coefficient D [m2∙s–1] 3.0×10–9 The composition undercooling has an inhibitory effect on kinetic undercooling, especially the concentration enrichment at the front of the solid-liquid interface strongly suppresses the increase in kinetic undercooling.
When the temperature gradient is less than the cooling rate, the temperature gradient does not affect the dynamic undercooling.

There are various requirements that the modern dressings have to meet: maintain a moist environment around the wound; permit diffusion of gases; stimulate the growth factors; provide mechanical protection; prevent the wound desiccation; non-allergenic; minimise pain from the wound; remove excess exudate; control local temperature and pH; be comfortable and easy to remove; cost effective and aesthetically acceptable and biocompatible and elastic.
However, still traditional wound dressings do not have suitable properties for modern biomaterials and specific wound applications [10, 11].
Results and Discussions The dressing dimensional properties are given in Table 2.
It was found that hydrocolloid dressings had the slowest solution uptake properties.
Another important finding is that the hydroactive dressings had better conformability properties.