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Since the laser cutting of wood is thermal in nature, the factors modifying the input of laser energy significantly affect the process.
The kerf width was affected by significant interactions between factors were focal plane position with traverse speed, power and traverse speed and power with number of gas jets [7].
Significance of factors and their interactions can be computed using statistical analysis.
It was depending on the material type and other conditional factors.
Rizman: Numerical and Experimental Analysis of Activated Carbon Filter on the Mechanical Properties of Wood Composites.

The defects can affect the safety of pipelines, and even depress their service life; may lead to enormous economic costs and jeopardize the surrounding ecological environments.
Shown in Fig.2 and Tab. 2 are the stress-strain curves and mechanical properties of X60 pipeline steel after pre-tension defamation.
Fig.2 The stress-strain curves after pre-tension defamation Tab.2 Mechanical properties of X60 pipeline steel after pre-tension defamation δt/% E/GPa σs/MPa σb/MPa δ/% ψ/% 0 198 471 543 20.05 65.20 5 198 542 571 17.96 62.63 10 198 587 608 12.56 55.87 15 198 601 618 8.87 49.02 The fracture strength σf and the fracture ductility εf can be estimated by the material’s tensile properties: (1) (2) Caused to the obviously necking phenomenon, the average fracture strength can be corrected by Bridgeman Formula [14]: (3) where rf is the minimum radius while sample fracture, Rf is the radius outside necking zone.
The stress-strain of steel is coincident with Hollomon Formula: (4) The work-hardening exponential n can be obtained by Eq.5: (5) The fracture properties of X60 pipeline steel after pre-tension defamation are showen in Tab. 3.
Tab.3 The fracture properties of X60 pipeline steel after pre-tension defamation δt/% σf/MPa εf/MPa n 0 898 1.056 0.077 5 930 0.984 0.062 10 949 0.818 0.059 15 921 0.674 0.056 Effects of Prestrain on the Fatigue Crack Initiation Life.

Study indicates: for the concrete lining with initial damages, under the repeated aerodynamic fatigue loads, the mechanical properties of the tunnel lining concrete will gradually deteriorate to the whole damage of the concrete structure, which will cause serious inference on the durability of the tunnel especially during the middle and later periods of the high-speed railway tunnel serving.
The material properties were shown in table 2.
The fatigue damage micromechanics properties at different cycling times was got by simulating the lining concrete with initial pores, as indicated in figure 3.
With the repetitive action of the aerodynamic fatigue loads, the new cracks will generate from the mortar or the concrete interface layer, the existing and the new interlace with one another to affect the mechanical properties of concrete adversely.
We can conclude that the aerodynamic loads resulting from the train operation have great influences on the durability of tunnel concrete structure, and the influences will increase with the joint action of the lapse of time and the unfavourable external factors.

Introduction Shrinkage is one of the main adverse properties of concrete, which will result in crack and severely affect the mechanical properties and durability of the concrete.
One of the factors affecting the shrinkage of concrete is the chemical shrinkage of the cementitious material, so that the chemical shrinkage of cement has been much accounted [1-5].
The chemical compositions and physical properties of the materials are shown in Table 1.
Fig.1 Device for chemical shrinkage test Table 1 Chemical composition and physical properties of materials Material Slag Fly ash Cement Magnesia Bulk oxide composition SiO2 (%)a 33.70 50.76 21.44 - Fe2O3 (%) 1.25 4.04 3.54 - Al2O3 (%) 14.63 30.37 4.95 - CaO (%) 36.58 3.53 64.3 - MgO (%) 1.38 1.09 1.39 97.10 TiO2 (%) 0.48 0.22 - Na2O(%) 0.36 0.42 0.29 - K2O(%) 0.58 1.25 0.69 - SO3 (%) 1.71 4.82 2.36 - Loss on ignition (%) 2.49 3.32 1.59 1.05 Physical properties Density (g/cm3) 2.89 2.18 3.12 3.20 Blaine specific area (m2/kg) 455 386 305 295 a Percentage by mass Results and discussion Effect of fly ash Fig.2 shows the chemical shrinkages of OPC, AASC and the AASC added with 30% and 40% fly ash.
Strength and shrinkage properties of alkali-activated slag concrete containing porous coarse aggregate [9] A.R.

Much of this is associated with mechanical damage arising from digging or excavating by machines.
The chemical composition of the pipe steel is given in Table 1 and its mechanical properties are detailed in Table 2 (measured on full-thickness longitudinal direction).
Table 2 Tensile properties of APIX52 steel Stress strain curves have been fitted according to Ludwik's law n K . (6) where n is the strain hardening exponent and K is the hardening factor.
The obtained safety factor is then Fs = 2.97 for a 7MPa internal pressure Table 6 Obtained values of the effective distance, effective stress, notch stress intensity factor and hoop stress for the conditions described ef (MPa√m) Xef (mm) K(MPa√m) (MPa) 343 0.67 15,8 125 Table 7 Material properties and calculated values of parameters kr and Sr.
Recent studies [10-11] have shown that fracture toughness can be strongly affected by specimen size, crack depth and loading configuration.

We take the bicycle in the sports training sports as the research object and establish mechanical model of it.
Through the observation and research, we can see that there are two main factors affecting sport of cycling: the offset of direction angle in the process of driving and its movement speed.
According to related stress of the two sports, we can build the mechanical model.
Calculating Thermodynamic Properties of an Ionic Liquid with Monte Carlo Simulations with an Orthorhombic and a Cubic Simulation Box.J.
A Monte Carlo Simulation for a Uniform Ladder of Energy Levels: Statistical Thermodynamic Properties.

Other advantages like corrosion resistance [5], interesting magnetic properties, high strength to weight ratio and heat resistance can be achieved by cold welding.
As described by [6] the bond strength of metal joints due to the plastic deformation depends on different factors, such as surface conditions, temperature, and surface enlargement.
According to the model of Bay [15] and Zhang [17], the effective surface exposure, which is determined by the surface enlargement after the breakup of the covering layer, and the contact stress at the weld interface, are crucial factors affecting the bond strength.
However, in addition to the surface enlargement, the occurring stress at the interface is also affecting the weld strength and weld formation.
[11] Springer, H., Kostka, A., dos Santos, J., Raabe, D.: Influence of intermetallic phases and Kirkendall-porosity on the mechanical properties of joints between steel and aluminium alloys (2011).

Compared with the domestic widely used air/hydraulic brake system, the full power hydraulic brake system has the properties of simpler circuit, closer structure, faster brake and easier maintenance.
Brake valves are the key hydraulic parts in the full power hydraulic brake system, the property of which is closely related to the safety and running properties of the vehicles.
Only when the dynamic behavior and other related factors in the brake valves and the brake system are kept under control during the braking can the basis be supplied to the anticipation and analysis of the brake system design and match and the whole brake property.
Brake system and hydraulic brake valve The main properties required by the double-circuit full power hydraulic brake system of the off-road vehicles: The pedal force is to be proportional to the pressure of the brake system.
The parts that affect the property of the off-road vehicle brake system are brake valves, accumulators, checking cylinders and pipes; the most critical part is brake valve.

Feedstock having multi-polymer components showed better rheological properties than those having mono-polymer because of good wettability between powder and binder, and less sensitivity to temperature and shear rates.
Factors that influence the feedstock properties include processing variables such as speed and time of mixing, geometry of mixing blades, raw material feed rate, processing temperature, and material variables such as particle characteristics, solid volume fraction, binder composition and viscosity [4, 7].
The purpose of this study is to see the affect of various wax-based on the rheological property of the feedstock, in order to seek a suitable binder for the injection molding of tungsten-based heavy alloys. 2.
The purpose of Mechanical alloying was to avoid the powder agglomeration problem.
It was also found that feedstock having mono-polymer components exhibited poor rheological properties compared to multi-polymer.

Introduction Hetao irrigation area due to the cold climate, so the conveyance channel lining structure is vulnerable to frost heaving damage, not only greatly affect the normal use of the channels, and also spends a lot of human and material resources to carry out repair and reinforcement.
The ignored channels longitudinal impact factors, take the unit length of the composite lining structure analysis and the establishment of a simplified mechanical model.
Channels composite lining structure for frost heave mechanical model of solving The mechanical properties of the composite and the material properties of the material mechanical force big difference [7], in composite lining structure by unidirectional tension tensile force in the form, its interior will produce both tensile and shear deformation -- tension shear coupling; force in the form of composite lining structure by bending role, its internal bending and torsion two variants - the bending and torsion coupling; by a more complex form of the force, it will produce the four basic deformation of the coupling effect.
In accordance with the literature simplified mechanical model for stress analysis[8].
Conclusions 1) According to the trapezoidal channel composite lining the frost heave simplified mechanical model, design and test methods for composite lining structure to overcome the past, empirically and tectonic blindly selected cross-section of the defect. 2) Frost heave force composite Lining Internal Force calculation method provides a theoretical basis for the control of internal forces of the composite lining structure, improve the cracking resistance of composite lining structure. 3) This paper built a mechanical model only takes into account the impact of frost heaving force, while ignoring the normal freezing action, from the view of the material properties of the composite lining structure and engineering practice, in line with the actual engineering.