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The formation of jet influenced by many factors, such as liner material, liner shape, liner size, the shaped charge material properties and the charge structure, ways of initiation and blasting height [2], is extremely complicated to investigate various factors through the analytical calculation mechanic.
The mechanical behavior subject to liner loading at high strain rate, involves the geometry, material and contact nonlinear, which doesn’t only contain the influence of material under large strain, different strain rate and temperature on stress-strain relationship, but also the material damage and failure [3].
Table.1 TNT and LX-14 explosive parameters and state equation parameters Explosives Density (） Velocity （m/s） （Gpa） PCJ（Gpa） A（Gpa） B（Gpa） ω TNT 1.63 6930 6 21 373.8 3.75 4.15 0.9 0.35 LX-14 1.835 8800 10.2 37 826.1 17.24 4.55 1.32 0.38 Liner materials as copper, using the fluid-elastic-plastic model and Gruneisen state equation [5] to describe dynamic response behavior of the Liner affected by the detonation wave, can be used to simulate material deformation under the high strain (> ) conditions.

Roasting method Roasting method prepares the high-purity alumina through precise sintering temperature, heating rate and annealing temperature solid-state reaction temperature factors [2].
Lower temperature will affect the product capacity, and higher temperature will increase the cost of energy consumption.
This method has the advantages of high-purity powders preparation process, preparation without mechanical mixing process, not easy to introduce impurities, and good chemical homogeneity, particle dispersion and high purity [2].
Study on Influence Factors of Spherical Alumina Preparation Process[J].
Synthesis and Properties of Mesoporous Alumina with Poly-amidoamine Dendrimer as Template[J].

Guo 2,c 1 School of Mechanical Engineering & Automation, Northeastern University, Shenyang 110819, China 2 Brilliance Automotive Engineering Research Institute, Shenyang 110141, China a ytyan@mail.neu.edu.cn, bzhlsun@mail.neu.edu.cn, cguorj360@126.com Key words: spiral bevel gears; transient thermal analysis; loss of lubrication; finite element analysis Abstract: Based on loaded tooth contact analysis of spiral bevel gears, the thermal analysis model and finite element model of spiral bevel gears were established by making use of tribological theory and thermal transferring theory.
Spiral bevel gears are among the key components of transmission systems of attack helicopter, and work under high-speed over loading, much failure of transmission systems betide the spiral bevel gears, which is regarded by the meshing performance, endurance and reliability as critical safety factors.
These would affect badly the capability, reliability and survivability of the gear transmission [5,6].
The friction coefficient is related to the experiment conditions, the load, the properties of lubricant, the geometry parameter and so on, and has higher sensibility to these factors.

As one of the most promising candidates of the Pb-free solder alloy, Sn-3.5Ag system has been studied in mechanical properties and interfacial reactions between solders and Cu substrates[8-9].
By making comparisons with their results, measured results of contact angle are sensitive to the environmental factors and are affected by number of factors such as viscosity of fluid, atmosphere, roughness and heterogeneity of the surface, temperature of the fluid as well as the substrate, quantity or volume of fluid spreading, etc[2].

This study addressed to develop biodegradable polymer membrane for gas separation and effect of solvent evaporation time to membrane morphology, gas separation performance and mechanical properties.
Nagaoka, Formation of surface skin layer of asymmetric polyimide membranes and their gas transport properties, J.
Hernandez, Mechanical, physical, and barrier properties of pla films, J.
Maruccho, Gas permeation properties of poly ( lactic acid ) revisited, J.
Lai, Effects of phase inversion and rheological factors on formation of defect-free and ultrathin-skinned asymmetric polysulfone membranes for gas separation, Sep.

In the usual high-temperature combustion environment, the chemical reaction proceeds very quickly, while the mixing process of diesel vapor and air is much slower, which is the key factor that constrains the diesel engine combustion rate.
In conclusion, when a droplet evaporates in the vicinity of others, its evaporation must be affected by others, therefore to group droplets evaporation, there must be some errors if they are considered as separate single one!
In conclusion, when many droplets are evaporating at the same time, each of them will be affected by the other surrounding droplets, moreover, the smaller the distance is and the greater the effect is and the more slowly droplets evaporate.
Due to the restriction of experimental method, the influence of other factors such as the motion of air on the evaporation has not been researched in this paper, and there are some unstable factors leading to a few errors in the experiment, all of these flaws and scarcities will be consummated and improved in the later research.
JSME INTERNATIONAL JOURNAL SERIES II-FLUIDS ENGINEERING HEAT TRANSFER POWER COMBUSTION THERMOPHYSICAL PROPERTIES, 1989, Vol 32, Issue 2, pp: 265-272 [10]H.

To show the applicability of the model, some evaluation of material properties and simulation results of hole expansion test are discussed.
Introduction Precise prediction of a material anisotropy is a significant factor of an accurate sheet metal forming simulation.
Application Prediction of material properties.
The material properties are opened to the public for the benchmarks problem of NUMISHEET 2018 [6].
The proposed model describes the yield surface by the interpolation using all multi axial tension test properties.

Introduction Porcelains are attractive restorative materials because their physical properties closely match human enamel including hardness, density, thermal conductivity, refractive index and translucency [1].
In dentistry, the mechanical preparation and final adjustments of porcelain veneers, crowns, inlays and onlays or the removal of failed prosthetic parts involve the applications of high-speed handpieces and abrasive dental burs [2,3].
Machining-induced damage consisting of cracks and edge chipping in porcelains is often a major factor for limiting the clinical longevity of restorations.
However, there is no published quantitative information on how the diamond burs affect the degrees of subsurface damage in intraoral adjusting of porcelain prostheses.
The mechanical properties of the material are: Vickers hardness H = 6.2 GPa, Young's modulus E = 68 GPa, fracture toughness KIC = 0.9 MPa.m1/2, strength σ = 100 MPa, and Poison's ratio = 0.2 [11,12].

In the first part of the paper, the optimization of the cruciform specimen by thermo-mechanical FE analyses is outlined.
The work presented in this paper is part of a research project, which aims at developing a general approach that will be able to offer accurate evaluations of the influence of process parameters on the properties of final sheet components produced in hot forming operations.
In the first part of the paper, the optimization of the cruciform specimen by thermo-mechanical FE analyses is outlined.
This allows avoiding disturbs due to electromagnetic noise generated by the induction heater that could affect traditional measurement devices such as thermocouples and al..
Ohogami: Properties of Aluminium-coated Steels for Hot-forming, Nippon Steel Technical Report N. 88 July 2003

As far as mechanical systems are concerned, uncertainty effects have been mostly dealt with in the past with regard to durability issues, analysing in a probabilistic and risk-based perspective the ability of the component to survive the service loads for a given design lifetime.
The paper is organised as follows: Section 2 describes the method used in this paper to estimate by means of multi-body simulation the critical speed of the vehicle, and introduces the parameters affecting the calculation and how uncertainty shall be considered on these quantities.
Clearly, the maximum admissible speed of the vehicle shall remain below the critical speed by an appropriate safety factor, so to guarantee that the vehicle can provide the required performance in terms of maximum service speed without undergoing dynamic problems which would seriously compromise the ride comfort, because of accelerated degradation of both the rolling stock and the infrastructure, and in serious cases might even affect the running safety.
A full factorial plane is design to account for parameter interaction and non - linearity. [12]. the factors level are representative of the parameters range of variation; vi.
Furthermore due to the higher standard deviation value, the probability of the critical speed exceeding the imposed thresholds has similar value, besides the OAT evaluation is conservative, being higher the probability of meeting the critical speed computed Table 2: OAT and DOE&MCS method comparison OAT DOE&MCS Mean Critical speed [km/h] 271.0 270.8 Std Critical speed [km/h] 3.9 2.8 Pf (Vcr<264 km/h) [km/h] 3.5% 0.6% 6 Conclusions This paper presented a study finalised to the investigation on how parametric uncertainty can be treated in the framework of railway vehicles design in respect to vehicle dynamics, considering uncertainty in the yaw damper properties and considering full correlation between parameters of all dampers in the vehicle.