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This combinatorial explosion on GA factors and its values makes it extremely difficult to evaluate the effects of parameters settings on GA performance.
This property makes exact algorithms based on enumeration, extremely time consuming and inefficient.
The selected designed matrix is a standard central composite rotatable four-factor five-level factorial design with 31 experiments.
For any parameter, larger t-value and smaller P-value indicate that the factor is very significant.
As indicated in Table III, the most important parameter affecting GA's solution quality is the probability of mutation (Pm).

Hard anti-stab clothing is usually produced in metal materials, which featuring the physical and chemical properties, such as low weight, high strength, high hardness, corrosion resistance and other characteristics.
They mainly use their own unique chemical properties to enhance the anti-puncture performance.
In addition, because of a high degree of process complexity, these two methods can not applied in mass production, industrialization will be affected.
Since Fabric structure is different, the corresponding mechanical properties, protective performance are not the same.
Increasing the density and tightness of existing materials: While researching the anti-stab mechanism of other weft knitted fabric, Qiu Guanxiong, Jiang Yaming point out a way to improve the anti-stab-performance of materials, he need to develop a better shear properties of new materials and improve existing materials’ density, because density is a very important factor.

Introduction Nanotechnology is facilitating technology that allows us to develop materials with improved properties[1].
CNTs possess many unique electrical, thermal, optical and mechanical properties.
Several studies have focused on material properties of carbon nanotube-reinforced composites (CNTRCs) and have shown that the introduction of carbon nanotubes into polymers may improve their properties.[6] CNTs are well known for their excellent rigidity, higher than that of steel and any other metal [7].
Therefore, by changing the properties of the material it is possible to perform a certain function of material properties of mechanical strength and thermal conductivity [12-14].
This special attention arises from their outstanding electrical, optical, thermal and mechanical properties in combination with their extraordinary chemical stability [21,22].

Multilayer coatings combine the favorable properties of different materials in one system.
However, due to the different thermo-mechanical properties of the ceramic and metallic material, residual stresses arise.
Simultaneously, the geometry factor k and the information depth ξ changed.
Viera, Effect of ductile layers in mechanical behavior of TiAlN thin coatings, J.
Herper, Influence of multilayer designs on their residual stresses and mechanical properties, Applied Surface Science 257 (20) (2011) 8550-8557

The microseismic monmonitoring of hydrocarbon field development is a modern innovative technology for studying borehole space, migration processes of formation fluids arising from changes in initial formation conditions in a natural reservoir during the production of oil, gas, condensate and water, as well as physical and mechanical properties of rocks in situ, cracking processes during the interventions.
The surface observation achieves high operational efficiency and good horizontal localization accuracy, but the problems are noise from surface sources, inaccurate knowledge of the upper part of section (UPS), and the influence of weather and seasonal factors.
The development of hydraulic fracturing fractures is not purely "mechanical", but geostochastic ("probabilistic"). 11.
Each subsequent stage of MFHF affects the results of the previous stage, the state of the already existing zone of fracturing, up to a change in the direction of the fracture development.
Technological risks and success factors, Geophysics 1 (2010) 23-28

Non-Isothermal Simulation of Melting Process in Twin Screw Extruder Based on Two Typical Screw Configurations Liang Chang1, a, Luo Bing1, b and Wang Kuisheng1, c 1 Mechanical and Electrical School, Beijing University of Chemical Technology,15 Beisanhuan East Road, Chaoyang District, Beijing,100029, China aliangchang@mail.buct.edu.cn, bluobing@mail.buct.edu.cn, cwangks@mail.buct.edu.cn Keywords: Heat transfer; Numerical simulation; Twin screw extruder.
We can see that velocity gradient is a main factor to affect the magnitude of the viscous dissipation
Material Properties HDPE is chosen for this study.
The properties of the material are shown as Table 3.
Table 3 Material properties Properties Value Density [Kg·m-3] 950 Thermal Conductivity [W·m-1·K-1] 0.5 Specific Heat [J·kg-1·K-1] 2302 Melting Heat [J·kg-1] 21160.7 Liquidus Temperature [K] 420.8 Solidus Temperature [K] 407.5 Results and Discussions Temperature contours Temperature fields of two configurations are shown in Fig.3.

Introduction Compared with cast magnesium alloy, wrought magnesium alloy has higher strength, better scalability and more diverse mechanical properties, while the cost of production is lower.
MgO, Mg2SiO4, MgSiO3 and MgF2 have high temperature resistance, thus the heat resistant property of microarc oxidation coating is good.
According to the above analysis, the pulse voltage is a crucial factor which affects the microstructure and corrosion resistance of the microarc oxidation coating of AZ80 magnesium alloy.
Lei, Electrochemical properties of microarc oxidation films on a magnesium alloy modified by high-intensity pulsed ion beam, Surf.
Li, Duplex surface modification combined with micro-arc oxidation and polymer plating on AZ31 magnesium alloy and their functional properties, Chin.

However, if the thin-walled structures under dynamic loading conditions, inertial effects and the effects of strain rate greatly affects the structure.
The properties of this material are as shown in table 1.
Material properties of specimens (Tensile Strength) (Yield Strength) MPa MPa 353 265 20 mm (t) (b) (L) (a) (b) Fig 1.
Quasi-static testing Finite Element Method Geometry Model and Properties of Materials.
The material properties of impactor are assumed much more rigid than tube, therefore impactor modeled as rigid bodies.

In order to enhance its mechanical behaviour, it is usually subjected to secondary deformation operation.
The strength coefficient, K, and strain hardening exponent, n, define this phenomenon, which is a material property and can be obtained through experimental investigation for any composed material.
It has been reported that the aforementioned phenomenon largely affect by the process parameter particularly due to preform geometries, lubricant or friction condition, initial density and so on [4-6].For instance, if preform deformed under lubricant condition, the deformation would be substantial, but that does not support the closure of pores at faster rate, whereas the vice versa is observed in dry friction condition.
This indicates the pore closure or densification is governed by several factors and is totally non-linear behaviour.

The structure of three beams and four column is adopted by the Y32－315T experimental test special-purpose press for college of mechanical and electrical engineering of central south university.
The principle is: When the |φ| is smaller, Kd should be larger; when |ec| is larger, Kd should be smaller and Kd is usually medium. 2.3 Make certain of membership function and control rules Assume that the basic universe of deflection angle φ and its change rate △φ are respectively φ∈[-φ0,+φ0], △φ∈[-△φ0,+ △φ0].According to the need of fuzzy operation, Kφ and K△φ are transformed to normalized universe through quantization factor, the discretized universe of φ and △φare divided into 13 grades, Xφ={-6,-5,-4,-3,-2, -1,0,+1,+2,+3,+4,+5,+6},X△φ={-6,-5,-4,-3,-2,-1,0, +1,+2,+3,+4,+5,+6}, its corresponding linguistic variables’ fuzzy set is{ neglarge, negmedium, negsmall, zero, possmall, posmedium, poslarge}, its symbolic representation is {NB,NM,NS,ZO,PS,PM,PB}.
Fig.5 Membership function of deflection angle Fig.6 Membership function of deflection angle’s change rate △φ Take it for granted that PID maximum parameters are respectively Kp0, Ki0, Kd0,and actual universe of Kp, Ki, Kd are respectively [-KP0, +KP0], [-Ki0,+ Ki0], [-Kd0,+ Kd0], and they are transformed to normalized universe through quantization factor Kup, Kui, Kud, the discretized universe of UP, Ui, Ud divided into 13 grades, they are all {-6,-5,-4,-3,-2,-1,0,+1,+2, +3,+4,+5,+6}, use{ neglarge,negmedium,negsmall,zero,possmall,posmedium,poslarge }, its symbolic representation is{NB,NM,NS,ZO,PS,PM,PB}.
The simulation results show that fuzzy self-tuning PID control has low overshoot, short adjusting time, good dynamic and static properties and better adaptability and robustness compared with common PID control.
Chinese Journal of Mechanical Engineering, 2004.3 [3] Wu Yanmin, Cui Guangzhao.