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In fact, the process is not energy-consuming compared to thermo-chemical processes such as carbonizing and nitriding because it allows generating high power and focusing it locally and during a short time to achieve hardness at the surface area without affecting the part core.
A developed 2D model includes the coupling between electro-magnetic and thermal fields, and takes account of the non-linear behavior of material properties versus temperature.
The model developed by simulation should take into account the influence of machine parameters (such as frequency, currents density, and heating time), material properties, inductor characteristics, and part geometry [4-5].
The appropriate frequencies and power amount to deliver to part depend on dimensional factors and geometry to be heated.
For the two cases, where the dimensional factor is 2 and 0.5 respectively, the teeth number is kept the same and only the scale factor is modified.

From the development of HVFAC, application technology of HVFAC is largely advanced by two main factors which one is the building dam technology of RCC and other is increasingly popularized about water-reducers, especially superplasticizer in 1970s.
Reference [7] results have shown that low quality fly ash concrete may develop same mechanical property with ordinary concrete in reinforcement bending structure, and the common workability of concrete and steel reinforce bar is not affected by low quality fly ash.
Though carbonation resistance is related to many factors, it is one of important factor for carbonation using up Ca(OH)2.
Properties Improving Through many studying results and application have shown that the properties of HVFAC is used enough in structural concrete, some inadequate properties of HVFAC is obvious.
[9] Lin Jiaping.et al: Study on Physical and Mechanical Properties of Roller Compacted Concrete with Fly Ash for High Way Use , International Symposium on New Development in Concrete Science and Technology，Nanjing Publishing of Southeast University, 1995, pp.499-506

Probability theory determines how the uncertainties in crack size, loads, and material properties, when modelled accurately, affect the integrity of cracked structures.
The method can account for random loads, material properties, and crack geometry.
,X characterizing uncertainties in the load, crack geometry, and material properties.
The calculation of stress intensity factor affected by the randomness of crack size, elastic modulus and far field applied stress magnitude.
The load, crack size and material properties were treated as statistically independent random variables.

On the basis of an in-depth analysis of the actual problem, decision problems according to different properties are broken down into several levels.
Determination the Weight of the Decision Criteria In terms of impeller machining route,the expert believe that in the main goal level costs is slightly more important than quality,quality is slightly more important than green properties,and green properties is slightly more important than time.So the pair-wise comparison matrix of the four main criteria is created in Table 4.
The weight of the time, costs, quality and green properties is presented in Table 4.
Table 10 presents the four criterion factors that affect the selection of the processing route of mine fan’s impeller( Example: Axial Flow Fan No6.0/2×15:the diameter of impeller is 0.6m,grade 2,and the single motor power is 15KW); The decision criteria when the performance of alternative is evaluated is short processing time, good product quality,low cost and good green properties; And in accordance with the recommendations of the expert.
Table 5 Pair-wise comparison matrix of alternatives to decision criterion Criteria A1 A2 A1 A2 1 1/5 5 1 0.6000 0.4000 Table 6 Pair-wise comparison matrix of alternatives to decision criterion Criteria A1 A2 A1 A2 1 3/2 2/3 1 0.3333 0.6667 Table 7 Pair-wise comparison matrix of alternatives to decision criterion Criteria A1 A2 A1 A2 1 3/2 2/3 1 0.6667 0.3333 Table 8 Pair-wise comparison matrix of alternatives to decision criterion Criteria A1 A2 A1 A2 1 1/3 3 1 0.6000 0.4000 Table 9 Alternatives’ total ranking calculated matrix Goal Ranking alternatives Ranking alternatives 0.1448 0.3964 0.2574 0.2014 A1 A2 0.6000 0.4000 0.3333 0.6667 0.6667 0.3333 0.3906 0.4079 0.6000 0.4000 0.5114 0.4886 Table 10 Types of impeller and the factors affecting their selection(one mine axial fan)[6] Factors Impellers Stamped by Using Steel Plate (A1) Impellers Casted by Using Aluminum Ingot (A2) Time 1.process time;2.auxiliarytime 255minutes 362minutes

Therefore, the shape and size of burr formed in machining are important factors to improve the surface quality of the workpiece and the machining efficiency.
As is obvious in the figure, a semicircle heat affected zone (HAZ) is observed, where the martensitic layer is formed in the ferrite-pearlite mother phase.
One of factors of burr formability is mechanical properties of the workpiece.
This is the reason why the burr formed in milling is able to be prevented by partially alteration of mechanical properties of the workpiece by laser hardening.
In case of higher laser density, burr is not observed so that the chipping (negative burr) is caused at the completely martensitic layer in the heat affected zone.

Table 1, Physical and mechanical properties of LWAs.
Mahmud, Mix design and mechanical properties of oil palm shell lightweight aggregate concrete: a review.
Karakoc et al., The influence of lightweight aggregate on the physico-mechanical properties of concrete exposed to freeze–thaw cycles.
Monteiro, Concrete: microstructure, properties, and materials.
Mahmud et al., A comparison study of the mechanical properties and drying shrinkage of oil palm shell and expanded clay lightweight aggregate concretes.

Therefore, the weldability, the welding procedure and parameters as well as the overall properties of T24 weld joints must be carefully studied and analysed.
The chemical composition and the mechanical properties of the used material are presented in Tables 1 and 2, respectively.
Kubon, Aplication properties of T24 welded joints for boiler waterwalls, in: PROMATTEN 2011. 1. issue.
Pecha, Experience with utility properties of the T24 steel, in: Zvaranie Svarovani-61. 1. issue.
Mohyla, Influence of the heat treatment temperature on the mechanical properties of low alloy creep resistant steel welded joints, in: 20th International Conference on Heat Treatment.

For the analyzing of this model is used factors experiment.
Table of real level values of factors of experiment N.
Factors Interval of factors Mark.
The microhardness is connected basically to the local changes in mechanical properties of the material. [3] It can be seen little difference in microhardess, that results in narrow HAZ.
Heat affected zone – zoom 200x Acknowledgment Paper deals with definition and evaluation of process factors and parameters of cut surface while cutting the material ISO Fe510.

However, the usage of plastic is limited by its mechanical properties and production possibilities.
Although engineers try to improve its physical properties all the time, their properties are many times lower than those of metal.
These two principal factors are the sources of forming fascinating shishekebab structure patterns and well-developed banded spherulites (depending on the polymer molecular weight) that occurred in semi-crystalline polymers and which are characterized by the higher mechanical properties than structures generally formed in conventional injection moulded samples.
In the second step, the mechanical properties of moulded parts were studied by structural analyses in FEM Ansys/APDL numerical solver.
Its mechanical properties are as follows: - Tensile Modulus E = 3000 MPa, - Poisson's ratio µ = 0,4.

(1) Impact-spread of the expressway accident “Exceeding speed limit” and “fatigue” are the main factors to leading to the expressway accident.
(2) Impact-spread of the urban road accident The road safety awareness of road users plays the most important role in factors which lead urban road accident.
Various factors arising road accident in recent years is shown in Figure 1, the reasons in the order are Drink driving, Fatigue driving, Speeding, Reverse driving, Illegal overtaking, Illegal Opposite driving, Illegal turns, Illegal carrying, Illegal parking, Illegal parking, Illegal U-turn, Illegal lane changes, Illegal lane and driving, Accidents, Pedestrian and non-motorized.
Fig. 1 Various factors arising road accident in recent years Forming of the Affection and Dissemination in Road Accident There are four main factors on impact-spread of road accident, which are people, vehicle, road and environment.
According to the statistics, 80% to 90% accidents occur in relation to the human factor.