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To assess the state of corrosion we used frequency signal analysis, where we observed the changes in dominant frequencies and growth of damping factor λ.
A short-time mechanical impulse (a hammer blow) is applied to the test specimen and is detected by means of piezoelectric sensors placed on the specimen surface.
Longitudinal waves, which propagate within the rod at a speed of about 5100 ms-1, can affect the concrete element oscillations.
Bílek: Monitoring of Cement-based Material Solidification, Focusing on Electrical Properties.
Luňák: Measuring of Concrete Properties during Hardening.

Based on the above mechanical model, the capacity expression of normal section for the CFRP reinforced specimen under axial compression is shown as Formula (1) (1) The above equation shows that when the specimen is under axial compression, the CFRP on the surface of specimen can give full play to its mechanical properties.
But when the specimen is in a state of small eccentric compression, the stress of CFRP on each surface is different, and the CFRP can not give full play to its mechanical properties.
The eccentricity of the specimens in each group is different but other factors are the same.
The result is that there is a greater restraining action near the eccentric side than the other side, which cause that the CFRP can not give full play to its mechanical properties.
Experimental study on the mechanical properties of concrete.

The mechanical properties of Potassium Dihydrogen Phosphate (KDP) crystal had been relatively well investigated, and it was reported that mechanical properties of KDP crystal are anisotropic corresponding to crystallography orientation.
Researcher Chen M.J. analyzed critical cutting condition for brittle-ductile transition of KDP crystals in ultra-precision machining, he stated the mechanical characteristics of KDP crystal anisotropy, the tool rake angle, and cutting parameters are main factors for ductile cutting KDP crystals [4,5].
The major frequency component, 67.1Hz, should be the result of mechanical anisotropic properties on {001} plane of KDP crystal, which have four periods.
Fang: Near surface mechanical properties of optical materials in deterministic micro-grinding (University of Rochester Publications, USA 1997)
Ma: Research on Mechanical Properties of KDP Crystal in Ultra-precision Machined Surface (Harbin Institute of Technology University Publications, China 2006)

Conversely, it has to be considered that cortical and trabecular bone densities vary from one patient to another due to a number of factors, which can influence the fixation conditions of the screws.
Materials and Methods The cervical plate used on this work (Fig. 3) is made of a Titanium alloy Ti-6A1-4V, with the following mechanical properties provided by the manufacturer: E = 102 GPa, υ = 0.30, Sy = 827 MPa.
Fig. 4 CAD model of the Cervical vertebrae C3- C5 In accordance to the cervical plate manufacturer and technical information, this bend does not affect the mechanical properties of the plate.
It is also considered that C4 is replaced by a bone graft with the same mechanical properties used in the rest of the vertebrae and being adjacent to the superior and inferior surfaces of C3 and C5 respectively [9].
Even though the 3-D model does not consider the thread geometry of the screws, the CAD software used to model these elements (Mechanical Desktop) allows applying mechanical properties to the cylinder so it can represent the fixation properties of a screw, considering the type of thread, pitch, and number of threads.

By the suitable selection of the conductor’s material we have an influence for this factors.
It should be emphasized that these changes in the electrical properties of aluminum are affected by the alloying element, its amount, and also its localization in aluminum structure (it can be localized in solid solution or in precipitations).
Mechanical properties of Al, AlMo, AlAg wires with different amounts of alloy additions The Table 3 shows the basic mechanical properties of wires after drawing subjected to uniaxial tensile test.
As it can be seen, the mechanical properties of both groups of aluminum alloys are at a similar level.
Effect of heat treatment on the electrical properties of AlMo and AlAg alloys Conclusions There are following conclusions based on the conducted research: · silver addition in the studied range of temperatures and times does not exhibit significant decline of electrical properties of aluminum, · silver addition in aluminum does not change its mechanical properties and results in a significant reduction of temperature coefficient of resistance, · a molybdenum addition in the studied range of temperatures and times exhibits higher decline of electrical properties of aluminum than silver addition, · molybdenum addition in aluminum does not change its mechanical properties and raises the recrystallization temperature of aluminum.

The harmful mechanical vibrations during the operation of mechanical manufacture are known to seriously reduce the machining precision and production efficiency even more destroying the whole manufacturing system.
Wang et al. investigated the mechanical properties and macro/micro morphological structure of woodpecker's head using a mechanical testing system and micro-CT scanning, and established a finite element model of the woodpecker's head to study the dynamic intracranial responses [4].
The two parameters are affected by environmental temperature and excitation frequency.
It can be seen from Fig. 5 that there is an incremental impact of frequencies on characteristics of storage modulus, loss modulus and loss factor.
The value of the loss factor increases with increased frequency, then the value keeps invariable after reaching certain extent.

When foundation is weak and there are differences in each layer’s density or material properties of subgrade filling, it is likely to appear situation (a) as possible as situation (b).
But due to the stability problem of wind-blown sand subgrade slope, when making analysis and comparison of subgrade slope stability in the situation of homogeneous filling material and situation of considering pavement materials properties and roadbed compaction partitioning, safety factor in theoretical formula of subgrade slope stability can be adopted to calculate wind-blown sand subgrade slope stability.
According to slope stability theory analysis results, when considering the subgrade upper part and materials properties of pavement layer , very small impact has been made on safety factor, and with the increase of height of the roadbed filling, its influence is getting smaller and smaller; Second,comparing with homogeneous filling material, the caculation safety factor considering subgrade upper part and pavement layer material properties has been increased slightly.
(2) But due to the stability problem of wind-blown sand subgrade slope, when making analysis and comparison of subgrade slope stability in the situation of homogeneous filling material and situation of considering pavement materials properties and roadbed compaction partitioning, safety factor in theoretical formula of subgrade slope stability can be adopted to calculate wind-blown sand subgrade slope stability.
One the basis of meeting the roadbed slope stability, desert subgrade can satisfy the mechanical stability of the slope.

Porosity and water content of concrete changing in wet-dry cycles were introduced, the failure mechanism of freeze-thaw and carbonation and the relation with pore structure, as well as its interaction influencing factors.
In recent years, some researchers have stimulated the damage of concrete by completing multi-factor.
Concrete affected by single destructive factor Wet-dry cycles.
In generally, carbonization rarely adversely affects mechanical properties of concrete and components [11].
Fitting carbonation depth of concrete which affected by Freeze-thaw test in natural environment.

The hardness properties of samples were between 477 and 551.4 HV (0.1).
Response in this design is hardness properties.
Statistical analysis of hardness properties is shown in Table 2.
Contour plot in Figure 1(b) shows desirability factor from optimization of hot press forming of 22MnB5 steel corresponding to hardness properties.
Effect of cooling rate on the high strain rate properties of boron steel.

Currently, research is generally on parameters optimization, movement and mechanical analysis, as well as load spectrum analysis of the cutting roller.
The relation between cutting resistance and coal rigidity Considering the influence of geometry shape, mine pressure, physical mechanical property of coal, the cutting resistance is: 0.5 0.35 0.3 1 cos ϕ β + = ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ +p z y c ot p b F A h t k k k k k b Bh .
The factors that influence the cutting ability Fig.2 factors affecting cutting ability Thus the factors that influence the cutting ability can be realized.
Fig.2 shows all factors to 12HM10 continuous miner.
College teachers innovate team project in Liaoning Province (08-117).Excellent youth science study fund at Mechanical Department of Liaoning Technical University, Excellent youth teachers science study and train plan fund in mechanical engineering department at Mechanical Department of Liaoning Technical University(07-75).