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Besides, the movement kinematics is determined by a number of external factors, such as: type of the movement, the load friction, the shape of the cooperating surfaces, the surface roughness, the type of lubricant, and finally the type of material association.
The last factors in addition plays a critical role in the effects on the body of the implant.
In this aspect, particularly important is the appropriate selection of biomaterials concerning their mechanical properties and clinical aspect of reducing their tribological wear during exploitation.
One of the limitations affecting the use of titanium alloys for knee endoprostheses is their low wear resistance resulting from the low tribological properties and high friction coefficient [4].
Bressiani, Mechanical properties and cytotoxic evaluation of the Ti-13Nb-13Zr alloy, Biomecanica, 8 (1), 2000

Practice shows that the type of kernel function, kernel parameters, and penalty factor is one of the key factors affecting the performance of the SVM, so research SVM parameter selection method for support vector machine development has a very important practical significance.
For a given set of observations:, optimal decision function can be constructed in a high -dimensional feature space: (1) Where w and b are regression factors, which can be gained by minimizing the following regularized risk function (2) Among them, control model complexity, C is the penalty factor to control the degree of experience in risk of punishment; is error control function, error control function commonly used linear loss function, quadratic loss function, select a different loss function can be constructed in different forms of support vector machines.
After a given training set and selected kernel function parameters that affect the performance of SVM main penalty factor and nuclear parameters.
Using support vector machine to predict, to select parameters is important, if the parameter is selected unreasonable, it may result in the calculation of under- and over- learning phenomena, which directly affect the prediction accuracy.
Journal of Mechanical Strength, 2008, 30(3):349-353

Among them we can mention: manifestation of breakage of fine particles in the vicinity of the free surface of screw outer zone, energy state and multiplication of dislocations in various superficial zones, influence of surface roughness on the resistance to wear, influence of oxide films and special coatings or of liquid environment on certain physical and mechanical properties of the superficial layer.
The following elements can be observed: A – upper element, B – lower element, ; a – zone of plastic deformation; b – zone with destroyed structure, c - zone of elastic deformation, 1- lubricating material interposed between elements A and B, 3 - microscopic particles produced in the process of wear; 4 – areas on the upper and lower element respectively that will enter directly in interaction; 5 – area with heavily modified physical and mechanical properties; 6 – representation of the limits of variation of the momentary speed values of various areas of fluid [1].
The quality of the oil in a compressor [12] can be affected by three main factors, namely: a) wear: solid microscopic particles of oil and particles detached from moving parts can cause the wear of the component elements, reducing the life of the compressor; b) chemical properties: abnormal viscosity because of oil temperature changes caused by moisture or high levels of acidity, resulting from internal chemical reactions (alteration of refrigerant or hydrolysis of oil).
The dimensions of the layers shown in figure no. 4 depend on a number of factors of the metal that constitute the compressor components and also of a number of factors exterior to the system.
Conclusions The most detailed knowledge of the superficial layer structure of the metallic elements of a compressor allows identifying the mechanisms that explain the response of the material to the generally destructive action of some exterior factors such as the mechanical, chemical or thermal factors.

(2) The mechanical properties of rock.
It is the rock properties shown under the mechanical external force.
It includes the strength properties (tensile, bending, shear, press four kinds of disturbance intensity), the deformation characteristics (elastic, brittle, plastic), and surface properties (hardness, abrasive)
(3) Non-mechanical properties of rock.
There are many factors to affect the risk of directional drilling construction; in general, there are three aspects of directional drilling construction risk: the owners passed on the construction risk, security risk, the risk of construction technology.

Fatigue problems about large sized structure components ,such as bridge crane girder , has always been the bottleneck of mechanical products lightweight, reliability, security.
Fatigue failure mechanism is very complex about bridge crane for a long period of alternating loads, because a lot of factors that affect the fatigue behavior[1,2,3].
The actual processing of welding influencing factors were ignored in the above analysis, then the local details of welded joint fatigue problem will be analyze the fatigue properties focus on the most dangerous position.
Fig5 Dangerous position in mid-span section Fig6 Dangerous position in 3D model Combined with welding process technology characteristics of their own technology to retain the weld heat affected zone and the consistency of the welding process and the process parameters of the actual bridge crane, characterized in figure 7 shows, determine the welded joints simplifying principles are as follows: a.

It is believed that the supramolecular structure is responsible for physical properties, the microstructure for mechanical properties, and the macrostructure for the coke thermal stability.
The coke molecular and supramolecular structure organization and the impurities presence determine its properties as a semiconductor, which allows us to evaluate coke some properties based on its resistivity.
Both factors contribute to a decrease in the lump coke electrical resistivity.
The electrical resistivity of a coke heap depends on same parameters as for a coke piece, but additionally factors such as fractional composition, contact density between individual granules, and the contact surface area appear.
Emen, Formation of fire dretardant properties in elastic silica coatings for textile materials.

Apparently, the presence of defect in the initial state showed direct influence on properties like lower tensile strength.
Suitable heat treatment of the material should be used to remove undesirable factors such as internal stress or heterogeneity.
Even though there are regions that are affected more than other the deformation occurs in whole sample.
Chawla, Temperature-dependent mechanical properties of an austenitic–ferritic stainless steel studied by in situ tensile loading in a scanning electron microscope (SEM), Materials Science and Engineering A 580 (2013) 159-168
Park, Effects of the strain rate on the tensile properties of a TRIP-aided duplex stainless steel.

High traffic load and temperature are the two critical issues that affect the quality of asphalt pavement.
However, an important factor for sporadic use and incidence are composite's financial demands.
Padevet, et al., Mechanical, hygric and thermal properties of cement-based composite with hybrid fiber reinforcement subjected to high temperatures, International Journal of Thermophysics, Volume: 30, Issue: 4, Pages: 1310-1322, Published: August 2009
Cerny., Effect of high temperatures on mechanical and thermal properties of carbon-fiber reinforced cement composite, Cement Wapno Beton, Volume: 13, Issue: 2, Pages: 66-+, Published: April 2008
Konvalinka, Permeability and basic physical properties of concrete with metakaolin addition, Applied Mechanics and Materials 486 (2014) 313-318.

Introduction Indentation technique has been developed for determining the mechanical properties of materials in small scale.
From instrumented indentation tests the micro-hardness, elastic modulus and other mechanical properties can be efficiently determined as reported in [1,2].
In Equation (2) is the peak indentation load, an indenter geometry shape factor on the order of unity.
When , the material is strongly hardened and the sink-in predominates, so that strain hardening does not affect contact area.
Dieter: Mechanical Metallurgy (McGraw-Hill, New York 1976)

Passenger thermal comfort is one significant aspect in cabin-related issues and it has become a key market competition factor for the civil airline industry.
The reduction of cabin pressure and very low RH at cruise altitude will affect several terms in the bio-heat balance equation.
We assume that the static theory of thermal comfort can be applied to the civil aircraft cabin and all the properties of the individual tissue as well as the insulation properties of garments worn are independent of the air pressure [5], air pressure and RH will mainly impact on the heat loss through skin diffusion and sweating, and heat loss by convection. 1) Heat loss through skin diffusion and sweating The evaporative heat loss from skin (Esk) is defined as [6]: (2) where w is the skin wettedness; Re is clothing water vapour resistance, m2Pa/W; pa is water vapour pressure, Pa; is the saturated water vapour pressure at the skin temperature, Pa
Such a low RH is believed to affect the basal wettedness of the skin, having a normal value of 0.06 which may drop to values as low as 0.02 in a very dry environment.
Personal factors in thermal comfort assessment: clothing properties and metabolic heat production.