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Significant factors that influence the coating characteristic are determined by using Analysis of Variance (ANOVA) and to develop a polynomial quadratic model.
The model is used to predict the grain size and indicates the effect of process factors to the TiN coating grain size.
In this study, the analysis of variance (ANOVA) is used to determine the significant factors influencing the TiN coating grain size and the present of interactions affecting the characteristic.
As shown in Table 2, the ANOVA analysis indicates that the turntable speed and Argon pressure quadratic term are the significant influencing factors of the TiN coating grain size.
Abdul Hakim, "Effect of PVD process parameters on the TiAlN coating roughness," Journal of mechanical Engineering and Technology, vol. 2, pp. 41-54, 2010

Polyethylene owes its popularity to an advantageous combination of properties, such as good biocompatibility, high mechanical strength and a low friction coefficient.
Changes in the structure of the polymer induced by irradiation cause a significant modification of its physicochemical properties, which, in consequence, affects its behaviour during operation.
In the case of polyethylene implants, post-radiation processes involving oxygen lead to the degradation of the structure and to changes of mechanical properties of the material [5-8].
Therefore, it is necessary to select the shaping factors in a way that reduces the influence of oxygen as much as possible.
Edidin, Degradation of mechanical properties of UHMWPE acetabular liners following long-term implantation.

Introduction The use performance of the mechanical parts can be affected by their surface roughness to a great extent.
The good surface quality can be obtained by grinding which is a precision machining method, but it is difficult to obtain good surface roughness when the material with the properties of high hardness and high brittleness is machined[1,2].
The factors and levels table and the experimental scheme table are shown in table 2 and table 3 respectively.
Table 2 Factors and levels table Factor Level Grinding wheel rotation speed, n[r/min] Workpiece feed speed, vw[mm/min] Grinding depth, ap[mm] 1 2500 100 0.005 2 4000 200 0.01 3 5500 300 0.015 4 7000 400 0.02 Table 3 Experimental scheme for the influence of grinding parameters on surface roughness Sequence number Principal axis, n[r/min] Workpiece feed speed, vw[mm/min] Grinding depth, ap[mm] 1 2500 100 0.005 2 2500 200 0.01 3 2500 300 0.015 4 2500 400 0.02 5 4000 100 0.01 6 4000 200 0.005 7 4000 300 0.015 8 4000 400 0.02 9 5500 100 0.015 10 5500 200 0.02 11 5500 300 0.005 12 5500 400 0.01 13 7000 100 0.02 14 7000 200 0.015 15 7000 300 0.01 16 7000 400 0.005 Experimental Results.
Modern Grinding Technology, Beijing:Mechanical Industry Press, 2003, p. 175-178

Introduction The initial stress field is not only a key factor that affects the mechanical properties of rock mass, but also an important power source that causes deformation and damage in the changing of environmental conditions [1].
The linear back analysis establishes a multiple regression mathematical model to solve the initial stress field by presenting the linear relationship between the initial stress field and the possible factors.
In the equation, is defined as the function of contributing factors for the formation of the initial stress field, such as the weight of rock mass, geological tectonic movements and etc.
For the influence of these factors can be equivalently simulated by applying load and boundary conditions into the finite element model, can also be regarded as the function of the applied load and boundary conditions.
By weighting all the three back analysis factors and the displacement and stress field of the model under unit load, the back analyzed field is gotten and the back analyzed stresses of ten measuring points are shown in Table 1.

More specifically, we show that leaf shapes are affected by genes and external environment in different species; and affected by leaf vein and leaf distribution In the same species.
Fig. 1: The reason of the different shape In macroscopical level, genes and external environment are the two key factors to effect the leaf shapes in different kinds of tree.
●Transform into spines to protect the plants, such as cactus In microscopic level, veins and the distribution of leaves affect the shape of the leaves in the same kind of tree.
Meanwhile, these three traits characterize properties of the terminal venation network: vein distance, density and loopiness.
High loopiness suggests more redundant paths for water to circumvent damage, and more ways to stop the propagation of a mechanical tear.

Study on cracking control of high performance concrete at early age Wang Yajun1,a , Wang Jianjun 2,b, GUO Changying1,c, Cao Mengxing 1,d 1Airport department of Air Force Service College, Jiangsu, Xuzhou 221006, China 2 The Seventh-Engineering Corps of China Airport Construction, Shanxi Baoji 721006, China awyj-1972@163.com, bwangjianjun-hm@163.com, cgcy733@163.com, dcaomengxing136@163.com Keywords: High Performance Concrete, crack, shrinkage, mix ratio Abstract: It analyzed the reasons for the early cracks in high-performance concrete, and prepared overall program to improve the mechanical properties and the durability of the HPC.
Generally, we should chose Portland cement with high 28d strength (not lower than grade 42.5) and good rheological properties, and good compatibility with super plasticizer.
These factors not only affected the strength of the concrete but also the work performance of fresh concrete.
In accordance with the judging method ASTM C1202, base concrete was concrete with low permeability, but concrete mixed minerals was concrete with very low permeability and its anti-CL- permeability and corrosion resistance properties were significantly better than the reference concrete.
Conclusion From the analysis above we can see, the HPC mixed with fly ash and mineral fine powder can achieve good mechanical properties and durability by reasonable adjustment of water-binder ratio and scientific selection on mineral admixture and additives.

After the preliminary thermo-mechanical treatment, the steel was subjected to cold rolling up to 85% of reduction and subsequent annealing in the temperature range 650÷950°C for various times.
Significant structural changes were observed in the course of annealing treatment affecting the formation of the ferrite and austenite texture.
Introduction Duplex stainless steels represented an important and expanding class of stainless steels with an attractive combination of mechanical properties and corrosion resistance.
From the point of view of the most important properties of these steels, the precipitation processes of inter-metallic phases are very important [1÷4].
The value of the PREN (Pitting Resistance Equivalent Number) factor was estimated within the range of 35÷38.

We investigate comprehensively the effect of dislocation behavior on the material property of nanostructured metal.
The UFGM, whose grain size is less than 1mm, expresses remarkably peculiar behavior in material and mechanical aspects [1, 3] and a computational model predicting these properties is expected in the field of materials science and engineering.
It is considered that such unusual mechanical properties are originating in enormous volume fraction of grain boundary.
We investigate comprehensively the effect of dislocation behavior on the material property of nanostructured metal.
It is predicted that such differences of dislocation behavior affect on softening of nanostructured metal.

Mangeron 67, OP-10, CP- 2000, Iasi 6600, Romania Keywords: DC conductivity; Water absorption; Diffusion; Cork, polymer properties.
Most applications of the cork are related with its cellular structure, which confers good thermal, acoustic and elastic properties.
This water produces significant modification of the electrical properties.
As it will be shown later, even after such a long drying time at room temperature, the sample still contains water that significantly affects the electrical properties of the material.
Conclusions The electrical properties of cork are significantly affected by absorbed and adsorbed water.

In many cases the acoustic properties of space of sound propagation have great importance.
In such cases, the sound levels depends on the distance from the acoustic source and will be affected by the shape of the area and position of absorbent surfaces, scattering of sound on machines and other equipment.
Summary In determining the expected sound levels in a confined space, it is necessary to know: - noise level of technology equipment; - position of assessed point relative to the position of source; - dimensions and cross-sectional areas of scattering bodies and their acoustic energy absorption coefficient; - shape of space and absorption of flanking areas; - other factors affecting the propagation of sound energy, such as temperature, humidity, etc.
Zajac at. el.: Reduce noise and vibration in mechanical facilities (in Slovak), Alfa 1990, ISBN 80-05-00674-8 [2] H.