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By simulation, the results show the phase locus has time ergodicity and chaotic characteristic with cutting drive system in different bifurcation parameters, realizing the simulation of chaotic simulating load signal; cutting drive system properties have important significance to develop efficient cutting working mechanism.
Introduction Spiral drum is an important working mechanism of shearer, whose power consumed is 80% -90% of installed power of shearer; its cutting performance directly affects the productivity and reliability of shearer [1].
Such as Figure 1 shows the cut-off contact with broken teeth with coal formed a, b, c and d phase coal and rock cutting pick of the stage and pick suffered the corresponding cutting resistance. cutting coal cutter rock the process is divided into two phases: one phase is starting from the cut tooth movement, the force gradually increased until the cutting conditions to the maximum; the other stage is the separation of coal block at this time rapid decline in force has been reduced to a certain value, whether it is the growth rate or rate of decline in force, is a quantitative index, with the cutting of coal by the physical and mechanical properties of the rock.
The experimental physics model of single pick cutting coal is shown in Figure 1, which is equivalent to pick cutting coal simulation process. 1 2 4 5 3 1—drive system 2—pick seat posit 3—pick-shaped cutter 4—cutting coal 5—cutting resistance Fig. 1 The physical model of single-pick cutting coal Pick-shaped cutter cutting resistance curve can be measured when a test simulation to determine the coal wall coal cutting resistance and cutting the equivalent thickness by using a single tooth cutting bench[4], it has a strong volatility result from the size change and coal's internal structure, hardness, and the crushing process and other factors.
organization mechanical and physical properties of coal determine its amount is controlled, generally ranging from x1 and x3, considering the pick of quality, the establishment of a single coal and rock cutting pick the chaotic dynamics model such as equation (7) of the said: 1 ξ2 111ξξξξ x3 x1 Ke K 2 3 ξ1 1-drive system 2- pick-shaped cutter 3-coal and rock Fig.3 The mechanical model of cutting coal by single pick ， （6） Where x1, x3 is pick invasive drive systems and displacement,m； Ke is drive system equivalent spring stiffness,N /m； mt, mf is pick equivalent quality and drive campaign,kg； ξ1, ξ2 is drive system and the coal equivalent damping,N/(m/s)； C is drive constant，N/(m/s)2.

Effective factors such as the different distribution of microstructure, the volume fraction of hard phase and the yield stress ratio between single-phase hard phase steel with single-phase ferrite steel in multiphase steel are discussed in this work.
Their useful properties are controlled by adjusting the type, size, fraction and spatial distribution of the different phases[9].
The elastic-plastic analysis with the finite element method (FEM) will give a lot of useful information about the mechanical properties of multiphase steel [10-12].
Therefore, the FEM used in this work is correct, which can be used for further simulation to analyze the affecting factors and discuss the distribution of micro-stress and strain of the multiphase steel.
Therefore, the finite element method (FEM) used in this work is correct and can be used for further simulation to analyze the effect of factors and discuss the distribution of micro-stress and strain of the multiphase steel

Rossetto1,e 1Politecnico di Torino, Department of Mechanical and Aerospace Engineering, Corso Duca degli Abruzzi 24, 10129 Torino aseyed.hasani@polito.it, bdavide.paolino@polito.it, candrea.tridello@polito.it, dgiorgio.chiandussi@polito.it, emassimo.rossetto@polito.it Keywords: VHCF; Gigacycle fatigue; Ultrasonic test; Gaussian specimen; size effect; critical SIF.
Several fundamental material properties can be estimated from the fracture surfaces of specimens failed during ultrasonic VHCF tests.
In the VHCF literature, the critical Stress Intensity Factor (SIF) is generally estimated by applying analytical SIF formulations to the typical semi-circular surface crack geometry revealed by fracture surfaces at final failure.
Introduction Critical Stress Intensity Factor (SIF) is one of the most important material properties to predict the onset of the unstable crack growth in cracked bodies.
Size effect thus affects critical SIF: the larger the size, the smaller the critical SIF.

A simulation of the drilling process helps to determine all negative factors affecting it and select the most suitable tools.
Autodesk Inventor is 3D mechanical CAD design software developed by the Company Autodesk, USA, for creating 3D digital prototypes of industrial products.
The real mechanical properties of soil, the borehole diameter and depth, and PDC bit pressure exerted on the borehole were accepted for the simulation.

Temperature-dependent material properties are also considered.
However, Park adopted a backup material whose material properties are twice as stiff and twice as strong as those of the workpiece material in his simulation.
The temperature-dependent physical properties of AISI 1045 steel are also considered in this study.
Similar to other factors (such as friction or flow stress), this value can influence the predictions and must be estimated with reasonable accuracy [12].
And the effects of cutting parameters and different backup material properties on the burr size will be investigated in the further study.

It is essential that the mechanical and thermal properties of the joints should meet the requirements of engineering.
In view of the fact that the ternary carbide Ti3SiC2 has shown unique mechanical and thermal properties, it is promising to join SiC to SiC using ternary carbide Ti3SiC2 as filler (welding compound), and this is the subject to deal with in this paper.
As a key factor for the application of the ceramic, joining of SiC to SiC has been investigated for some years [3,4].
It is anticipated that the favourable high temperature properties of Ti3SiC2 will contribute to the high temperature properties of the joints, and its plasticity will benefit the thermal stress relaxation.
The weld strength is strongly affected by the technological parameters.

The method of pressure processing or shaping deformation is the preparation technology for the production of mechanical engineering as well as the final product shaping technology, which not only allows to create the shape of the product but also high-quality metal products for mechanical-chemical, material saving and high labour productivity, thus lowering the cost of products.
Correct parameter sets will be selected through the variance analysis and used to simulate the finished product Material Properties Figure 1 depicts the stress strain curve for SUS304 stainless steel material used to produce the rice tray according to the continuous equation (1).
Using the Taguchi method will find the optimum data depending on the factors that affect the testing process and product quality as well as cost.
The friction coefficient is the most important parameter that affects the formability of a SUS304 material during deep drawing simulation.
The most important factor affecting the quality of the product and also optimum values will be determined by ANOVA of TAGUCHI method such as: clamping force - Q = 9 tons, friction coefficient - µ = 0,1and thickness of the sheet - a = 0,9 mm.

Two-dimensional model of asphalt pavement with cement-treated base was established based on mechanical parameters, thickness and homogeneity of commonly used structural layer in china, symmetrical and non-symmetrical load were both considered, and crack of cement-treated base was set before loaded.
However, reflective crack is a pervasive disease affecting serve performance due to temperature and dry shrinkage.
After the surface layer having been built, under the influence of repeated traffic loads, reflective cracks would easily occur because of temperature and other environmental factors.
An important advantage of this method, which simulates non-linear using non-uniformity, and simulates the non-continuum mechanics using the continuum mechanics, is to consider material′s non-uniform [1].The following is the analysis process to establish model: Assumptions 1) Ignore the longitudinal, cross-sectional displacement, and be simplified as a plane strain problem; 2) Materials of every layer are isotropic and continuous; 3) To ensure that the wheels would not deform because of the too big load, its strength and stiffness is set big enough; 4) Material′s properties meet Weber distribution, strength in line with Mohr-Coulomb Criterion; 5) Ignore material′s weight of each layer.
With the repeated loads imposed, strength weakening begins to appear around the original crack in the base, accompanied by the emergence of new cracks, affecting the stress field’s distribution, and the weak units further damaged.

Factors at the scene of the fire were explored such as smoke spread and changes in temperature.
The high carbon monoxide (CO) concentration and temperatures, and low smoke layer height caused low visibility levels, impeding firefighting and rescue operations at the fire scene; thus, these factors were explored.
The field commander must assess the circumstances at the scene to determine which firefighting tactics are appropriate considering the aforementioned factors
Visibility could have been improved by using smoke control equipment, but restricting factors at the scene (e.g., high temperatures) exacerbated the search for the origin point.
If factors at the scene (i.e., high temperatures, high CO concentration levels, and low gas layer height) result in low visibility levels, impeding rescue efforts, ventilation tactics should be employed instead.

Therefore, the current work focuses on using kenaf fiber due to the good mechanical properties and widely commercially availability of this material.
Due to of the elastic properties of constituent materials began to be insulted continuously.
Furthermore, reducing the mechanical properties in the region was destroyed affecting adjacent regions and accelerates Mode-III is associated with a brittle fracturing crushing and splaying mode.
Yuan, Improving the mechanical properties of natural fibre fabric reinforced epoxy composites by alkali treatment, J.
Al-shuja, Influence of fiber content on mechanical , morphological and thermal properties of kenaf fibers reinforced poly ( vinyl chloride )/ thermoplastic polyurethane poly-blend composites, J.