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This procedure allows for an accurate calculation of the stress at the start of the creep dwell, the creep strain, the related elastic follow-up factor and the total strain range during the load cycle [10].
The same material properties are adopted as those in [13, 14], and the temperature dependent yield stress is considered.
In this case the temperature transition does not move along the pipe direction, but across its thickness, affecting also the temperature dependent yield stress.
This stress relaxation allows the stress to redistribute and affects the location of the failure mechanism.
It has also been observed that the increase of dwell time affects the location of the failure mechanism.

Hot incentives include ultrasound, flash, mechanical vibration and electromagnetic, etc.
Due to many influence factors, new detection methods (e.g.acoustic emission technology, metal magnetic memory method are still not mature enough to be practically applied.
The purpose is to study the temperature features of the weld surface crack under eddy current heated, the impact of following factors on the temperature field distribution are numerical analyzed: a) orientation θ; b)excitation frequency f; c)crack length; d)crack depth; e) crack width.
The physical properties of all materials are listed in the Table 1.
Table 1 Material properties Properties Value Unit Structural Steel Copper Air Heat capacity 475 385 1.005 [J/(kg*K)] Density 7850 8700 1.205 [kg/m3] Thermal Conductivity 44.5 400 0.0257 [W/(m*K)] Relative permeability 200 1 1 [1] Electrical Conductivity 4.032×106 5.998×107 0 [S/m] Numerical analysis.

It is well known that the properties of such material are directly influenced by its structure which can be affected by several factors, including additive composition, physical parameters and the thermal process responsible for its preparation.
This promotes a reduction in water absorption and an increase in mechanical strength.
In this paper we present the results of our study and discuss the influence of such important parameters as the clay to ash ratio, and the sintering temperature on the technological properties like the bulk density, porosity, and the firing shrinkage.
This behaviour suggests that the existence of unburned carbon left in the ash is responsible for increasing the porosity, and this is one of the main factors that influence the decrease in bulk density.
Properties and Application (A review)”, Glass and Ceramic, vol. 60, no. 9 – 10, pp. 280 – 283, 2003

This is made to ensure that the flow at the inlet section of the duct is not affected significantly by the sudden expansion in the geometry at the step and the flow at the exit section becomes fully developed.
These contours show that the affecting zone of thermophoretic force is reducing while the Reynolds number is increasing and this can cause decreasing the chance of particles for deposition on the cold wall.
It is gained from this Fig that radiation effect can be negligible which is due to low radiative properties of air such as absorption coefficient, Table ΙΙ.
Physical properties of particles (silicon dioxide) Density (kg/m3) 2220.0 Specific heat (J/kg K) 745.0 Thermal conductivity (W/mK) 1.38 TABLE II.
Air properties Density (kg/m3) 0.8711 Specific heat (J/kg K) 1014 Thermal conductivity (W/mK) 0.0338 Prandtl Number 0.1 Absorption coefficient (1/m) 0.7 Albedo coefficient 0.5 References [1] N.

The cross-linking Ethylene-vinyl acetate copolymer (EVA) foam material is non-toxic and it has good properties [10].
The measurement of rheological properties of polymeric materials under molten state is crucial to gain a fundamental understanding of the nature of the processability for polymers.
It relates with several factors such as the weight of filler, the strength of cells, the size and size distribution of cells and the proportion of closed cells, etc.
And from SEM experiments, it also confirmed that the properties of foam were affected by cells structure which influenced by the content of poplar wood powders.
The foam has good properties when AC foaming agent was 11 wt%, DCP cross-linking agent was 0.9 wt%.

Therefore, ANN is suitable to deal with the uncertain and fuzzy problems where many factors and conditions are considered, and can also handle the problems that are difficult to be solved by the expert systems and statistical analysis methods.
Casting production is a complex process and many factors affect the casting quality.
Quality Optimization of Greensand Preparation The property changes of greensand are mainly caused by the component change.
Datta, “Controlling green sand mould properties using artificial neural networks and genetic algorithms-A comparison,” Appl.
Shi, “An optimizing direct-control technology of green sand quality based on the method of fast testing ingredients,” China Mechanical Engineering, vol. 18, pp. 2700-2704, November 2007

Traditional methods of masonry modeling are based on the use of generalized ("effective") mechanical properties of the composite as a continuant homogeneous continuant medium.
For isotropic materials, Ω invariant tensor measures are represented by k and q functions, which, in turn, express the change in the deformation properties determining the behaviour of materials (elements) under hydrostatic pressure and pure shear, respectively.
In this case, the framework of structural modelling is required to consider what properties belong to the local particle/element of the material in excess of one of the highest aggregate (system) of possible strength criteria.
The results of numerical experiments established that the scheme for the formation and accumulation of local damages, as well as the extent to which the elastic-plastic properties of masonry depend strongly on the value of the tensile strength in the adhesive layer of a horizontal mortar joint.
Deformatsiya i razrusheniye [Mechanical properties of metals.

The in-plane tensile test properties in MD, based on JIS-P8113 (gauge length: 180 mm, width: 15 mm, feed velocity: V=0.33 mm×s-1), are shown in Table 1.
Table 1 In-plane tensile properties of white-coated paperboard in machine direction Ultimate TS sB MPa 41.1 (40.2~42.7) Proof S. 0.2%strain MPa 11.1 (11.4~10.9) Breaking true strain eB % 1.71 (1.81~1.62) Young’s mod.
Figure 7 Relationship between factor a and b by varying nominal shear strain (1>g>0.2) and tracking angle a= p b +a0 (2) Here, the proportional coefficient p was approximately 0.054 when assuming a0 = 0.
The exponential coefficient –p appears to be varied with several mechanical or materials properties.
It was found that the tracking bending moment resistance at a certain large angle (e.g., Q=90 °) was remarkably affected by the rubbering condition.

The advent of nanostructured materials and the need to design microelectronic and micromechanical devices with length scales of nanometers require not only a profound understanding, but also a reliable prediction of mechanical properties of such structures.
From the comparison of the model results with experimental data we can conclude on the importance of the different influence factors on creep in thin films. 2 Discrete dislocation model A model of diffusional creep in a thin film geometry with a single grain boundary is set up here.
In the present work we have restricted ourselves to the case where the elastic properties of film and substrate are identical, which is a very good approximation for a copper film on a silicon substrate.
Nix, Mechanical properties of thin films, Metallurgical Transactions A 20 (1989) 2217-2245
These values mimic material properties of copper.

The inevitable working medium pollution, wear and tear between components matching surface, seal own aging and other factors in the process of the operation of the hydraulic system will lead to failure of seal ring.
Engineering practice shows that the main influence factors that affect the sealing ability and lead to seal failure include working medium pressure, pre squeeze rate, the sealing groove notch radius and the temperature.
According to the material properties of the O-ring, the paper chooses two parameters in Mooney - Rivlin strain energy function model that is currently widely used in analysis to describe sealing material.
（2） The location where the maximum contact strain on sealing groovegroove change with various factors.
Mechanical management and development, 2008, 01:49 and 50