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Spot welding is a very fast process, whose many factors affect the generation of welding defects.
Not only are experimental factors difficult to control, but also stress distributions are difficult to monitor in practical cases.
And Sawhill[4] obtained the effect on strength among the three factors of spot weldment as a function of welding pressure and welding current, experimentally.
The test was done by using the lap joint specimen, whose mechanical properties are shown in Table 1.
The objective functions were defined by using mechanical properties as follow (Fig. 1 and Fig. 2): (1) Tensile-shear strength for the maximization of joint strength and rupture strength (2) Increase of electrode force for preventive disperse (3) Decrease of indentation depth for good looking quality Table 1.

Assessment of the reliability of tailing dams is a complex task taking into account many factors that determine their condition, namely changes in technological parameters during TSF operations (dam height, slope, volume and type of stored material), significant variability of operating loads, impacts and soil properties of the tailings dam, which significantly complicates the choice of methods, calculating schemes and load combinations.
It is assumed that the strength properties of soils are accurately known, unchanged and homogeneous.
The essence of the probability approach is to determine the probability distribution function of the factor of safety (FoS), depending on the probability distribution functions of soil strength properties.
This software uses limit equilibrium theory to determine a critical factor of safety for slope stability of a geomechanical model, which describes the overall geometry, material zones with different strength properties and pore water pressure conditions.
The Mohr-Coulomb model is used to model soil properties containing three main input parameters: cohesion, friction angle and unit weight.

Special attention in contemporary dentistry is given to the oral health problems affecting children.
Carries lesions can affect the teeth in the primary dentition if good oral hygiene and nutrition are not established.
The decision to use 2D or 3D for analysis with FEM depends on many factors: complexity of dental structure, biological materials, properties etc [5].
The details of the mechanical properties of all materials included in the FE models are listed in Table 1.
Table 1 Mechanical properties of the materials involved in the FEM calculations Material E [MPa] u Bone 1,2x104 0,33 Tooth 2,686x104 0,33 Composite resin 1,83x104 0,35 Gic Fuji IX 0,4x104 0,3 Von Mises stress, which is always positive in sign and depends on the whole stress field, is widely used in dental literature as an indicator of the stress level in a restored structure [9].

These factors have resulted in various changes in the atmospheric environment.
The reinforcement impart their special mechanical and physical properties to enhance the matrix properties [5].
The physical properties of oil palm frond brick were different for each ratio.
George Oliver, Experimental studies on mechanical properties of glass fiber reinforced ceramic matrix composites.
Oliver, Experimental studies on mechanical properties of glass fiber reinforced ceramic matrix composites.

It's numerically analyzed the influence of main pipe's ramification due to modification of mechanical and geometrical parameters.
The obtained results represent a comparative factor for technical regulation in the safety assessment in operation of natural gas pipelines.
We consider for material behavior a bilinear isotropic hardening model, with thermal property according to Table 1.
Therefore, the thermal fields induced by the welding branch on gas main create a zone with stress concentration with implications on the level of residual stress, negatively affecting the operation of gas main safety.
So, for the safe operation of natural gas main is necessary to create favorable thermal fields to ensure adequate welded joint properties.

The influences of some basic factors such as the running speed, the axial preload, the oil viscidity, the design contact angle of bearing, and the ball materials and so on are analyzed on the heating performances in a bearing.
Because the affects are very small, it cannot be taken into account of the friction heating between the retainer and the rings, and so the air friction heating is.
It can be known that the materials with different properties such as the mass density, the elastic modulus and Poisson-ratio, will affect the inertial loads of the ball element, the contact stress and contact deformation between balls and both ring raceways, and will also affect the heating performances inside EHL films in the contact areas.
Zhang: Mechanical Engineer, Vol. 12 (2005), pp. 110-111 (in Chinese)
Li: Mechanical Engineer, Vol. 4 (2004), pp. 12-14 (in Chinese)

The resonance frequency of the cymbal transducer ranges from 2kHz to 40kHz and its effective electromechanical coupling factor is around 20%.
Finite element analysis has been performed to ascertain how the transducer’s makeup affect the transducer’s performance parameters.
The electromechanical properties and vibration modal of the cymbal transducer of the 10KHz-40KHz resonance frequency were researched [8,9,10].
The cymbal transducers of eight sorts of different structure parameter of 3KHz resonance frequency were researched by ANSYS FEM in this article, finite element model is discussed, strunture parameter influence on resonance frequency is debated, and computing the bandwidth, quality factor, efficient electromechanical coefficeent performance parameters, the cymbal transducer of better comprehensive performance is optimized [11].
The free-field voltage sensitivity curve According to table 1 and table 2, the -3dB bandwidth of the cymbal transducer of the 8mm cavity coping diameter, 20.8mm cavity bottom diameter and 26.8mm piezoelectric ceramic wafer diameter was the broadest and up to 400Hz, the mechanical quality factor and the electrical quality factor of the cymbal transducers of the 8mm cavity coping diameter, 22.4mm cavity bottom diameter and 26. 4mm piezoelectric ceramic wafer diameter, the 9mm cavity coping diameter, 21.6mm cavity bottom diameter and 27.6mm piezoelectric ceramic wafer diameter and the 8mm cavity coping diameter, 20.8mm cavity bottom diameter and 26.8mm piezoelectric ceramic wafer diameter were smaller, thereinto, the mechanical quality factor of the cymbal transducer of the 8mm cavity coping diameter, 20.8mm cavity bottom diameter and 26.8mm piezoelectric ceramic wafer diameter was the smallest and up to 8.75, while the electrical quality factor of the cymbal transducer of the 9mm cavity

Besides, factors and sub factors of evaluation object are obtained.
Based on the above analysis, the evaluation index factors of bridge crane are established as shown in table 1.
Table 1 Evaluation index factors of bridge crane Layers Factors Target layer F-Safety grade of main girder Criteria layer V1-Working environment V2-Design parameter V3-Manufacturing technology V4-Maintenance Index layer M11-Environment temperature M21-Dynamic stiffness M31-Material quality M41-Service time M12-Environment humidity M22-Static stiffness M32-Welding quality M42-Maintenance frequency M13-Acid-base property M23-Camber M33-Stress distribution M43-Operating M14-Corrosion degree M24-Horizontal bending M34-Crack surface M44-Loading M25-Stress amplitude M35 -Machining error M45-Lifting position M26-Web buckling M46-Working frequency M27-Maximum stress The target layer is F, namely safety grade of main girder.
Factors affecting safety evaluation of bridge crane is divided into four parts, given as follows
Mechanical Research and Application, 2009,No.3

Aluminum belong to a relatively active element, because it reacts due to various physicochemical and biological factors.
An additional procedure affecting the properties of Al-Si-Cu alloys is the modification most often with sodium, strontium, antimony (for hypoeutectic and eutectic alloys) and phosphorus (non-magnetic alloys) [1-4].
In this aspect, the usable properties are determined by the properties of surface elements made of these alloys, and not the properties over the entire active cross-section.
The authors evaluated the electrochemical and mechanical properties of the layers grown in the ranage from 100 to 400 °C temperature.
Nowińska, Influence of ALD process parameters on the physical and chemical properties of the surface of vascular stents, Archives of Civil and Mechanical Engineering 17 (2017) 32-42

The subsequent phase interaction mechanisms are quite complex and have direct effects on the flow and final micro-structure distribution of the cast part and thus, without any doubt, on its mechanical properties.
But any little variation in the process parameters will affect the next filling.
The power law model is not able to reproduce the pressure distribution in the mold which means that it does not replicate entirely the physical properties of the metallic slurry.
For the industry, a homogeneous distribution of the solid particles is preferred in order to maximize the structural and fatigue properties.
In a solidifying semi-solid flow, many factors can affect the particles size and shape.