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The influence on blade vibration amplitude have:  the level of aerodynamic and mechanical forces;  the lack of blade modal repeatability;  lack of compressor clocking optimization;  central support varied modal properties;  differences in production coaxial of compressor and turbine rotors;  differences in a level of compressor, shaft and turbine unbalance.
This phenomena describes increase of material nonlinear properties [16];  the occurrence of a blade crack - Fig. 3b), decrease of the range of excitations from the rotational-speed II harmonic by 1000 rpm (fn = 16.6 Hz).
The quality of the rotor balance and resonance properties of the central support also affects the amplitude of the compressor-blades vibration.
It is closely related to the resonant properties of the central support and the 1st stage compressor disc, and the way of frequency-based selection of blades for the blade cascade (of particular susceptibility are engines with blades of fIF = 348 ÷ 355Hz).
Statistical factors reflect effects of the "active control" efforts.

It is usefull to understand all kinds of factors and influence rules on residual stresses of FSW.
The fixture factor is considered in mechanical analysis.
Influencing factors on residual stresses in FSW The technological parameters in FSW are welding speed, rotational speed, tool pressure, shoulder diameter and geometry, outline of pin.
However, FSW is a complex coupled process with temperature change, organizational structure change, metal flow, the residual stress standard and distribution in FSW joints are effected by many factors.
Thirdly, in order to ensure safety and reliability of FSW structures, the residual stresses level and regularity of distributions should be researched from the degree on engineering application, Further works are proposed for the influence of residual stresses in FSW on mechanical characteristics, particularly fatigue properties.

Technical analysis Properties of materials.
CFRP materials have many excellent properties such as better vibration damping performance, higher carbonization temperature, non-toxic, tasteless, non-flammable, good durability.
The study shows that the mechanical properties of carbon fiber were not reduced on the conditions of strong base, freeze-thaw cycle, water immersion, hot and humid environment, it has a good durability.
The characteristic of material properties make FRP reinforcement technology is feasible in theory.
Owing to the effects of smelting, manufacture, construction, use and environmental factors, especially when the steel structure is close to or more than the design life, the steel structure inevitably exist various damage and defects.

The utilization of fly ashes produced by circulated fluidized bed combustion (CFBC) has been limited in construction application due to their inherent high sulfate and carbon contents although CFBC fly ash exhibits very good binding properties without requiring any supplementary activator.
For example, Diaz-Loya et al. reported that the mechanical behavior of FFA-based GPC is similar to that of ordinary Portland cement concrete [4].
Because of these abnormal chemical and physical characteristics, the use of CFBC fly ash in construction applications as concrete material has been limited although CFBC fly ash exhibits very good binding properties without requiring any supplementary activator.
Shon et al. [7] reported that the determination of activation energy for ASR is capable of providing direct accountability for a variety of important material-related factors that affect ASR behavior of mortar/concrete such as temperature, alkalinity, aggregate reactivity, humidity, and age.
Vaidya: Mechanical properties of fly-ash based geopolymer concrete.

a lxp810525@163.com. bdgzhou@njfu.edu.cn cswang@utk.edu Keywords: Castor stalk, Wood based panel, Thickness-swelling (TS ), Wax emulsion Abstract: Castor-oil stalk is one kind of excellent woody materials, and the thickness swelling ( TS ) of the castor-oil stalk based panel with Urea- formaldehyde resin ( UF ) cannot meet the requirement of the Standard of People’s Republic of China. the TS of the panel was improved with wax emulsion.Results showed that the mechanical properties and the TS of the particle panels were improved as the wax emulsion loading increased.
The properties including internal bonding strength (IB), the modulus of elasticity ( MOE ), the static bending strength ( MOR) and thickness swelling (TS), and the results shown in table 3.
Results and discussion The influence factors of the TS of the wood based panel Table 2 shows the TS of different wood based panel with different resin and materials made by different techniques .
It isbecause that it can generate the function rejecting water when the MDI resin react with woody materials, and the PF resin itself has excellent waterproof properties [13].
The relationship between the properties of the panel and the wax added emulsion were shown in Fig.4- 7.

The influence factors of the response time were researched.
There are two kinds of existing methods of focusing, 1) Ultrasonic energy focus by a piezoelectric ceramic transducer with a certain geometry (concave spherical surface) or through a solid lens, whose structure is simple but the focal length is fixed, so the only way to change the focal position is to adjust the place of the transducer using a mechanical method; 2) Ultrasonic energy focus based on the principle of phased array, which is to control the different initial states of each source unit to focus acoustic beam at the focal point.
The viscosity of the liquid material is an important influence factor to the response time of the liquid lens.
The thickness of the hydrophobic coating may also affect the response time of the lens system, as shown in Fig. 5.
Focusing Properties of Acoustic Fresnel Lenses [J].

In British Standard BS 5500 and ASME Section VIII Div.1, the temperatures at which time dependent properties must be considered are tabulated for generic material chemistry.
Previous studies show that failure of high temperature component is a combination of material and structural factors such as multiaxial stress state.
Therefore the choice of oσ does not affect the results of refσ .
The conventional method for calculation of creep fracture parameter of welded structures is simply based on the consumption that the welded structure is made of a homogeneous material with the lowest mechanical properties among those of the base material, weld material and heat affected zone (HAZ).
The proposed model has the same geometrical dimensions with the original one but without weld and thus it has different material properties.

The mechanisms are responsible for improvement of properties of modified material have been revealed.
The mechanical properties under study were hardness (Vickers method, PMT-3 device, Nanotest-100 nanohardness tester), bend and tensile ductility, and ultimate bending and tensile strengths (Instron-3369 testing machine).
Mondol’fo, The structure and properties of alloys, M.; Metallurgy, 1979
Bibik, Electron-ion-plasma treatment of Al-Si system: structure and properties, XX Petersburg Readings on the problems of strength, Part 1 (2012) 137 – 139
Nikonorov et al., Structure and mechanical properties of Al-Si (Ge) alloy under quenching and centrifugation of melt, Solid-state physics, V. 47, № 5 (2005) 886-892.

Design Principles of Controlling Vehicle Gear Whine Noise Based on Loudness Metric Dong Guo 1,2 a, Quan Shi 2,b , Wenli Li 1,2 c, Chuanhe Xu 2,d 1College of Mechanical Engineering, Southwest Jiaotong University, Chengdu, 610031, China 2 Key Laboratory of Advanced Manufacturing Technology for Automobile Parts, Ministry of Education, Chongqing University of Technology, Chongqing, 400054, China acgguodong@163.com, bsq@cqut.edu.cn, cliwenli999@163.com , dxuchuanhe13@126.com Keywords: design principle; vehicle; gear whine; loudness Abstract.
Introduction Interior vehicle noise is an important factor affect the ride comfort.
Absolute threshold curve shows a distinct valley around 3-4kHz and a peak around 8-9kHz ,which means sounds in these ranges are more detectable.Pure tone case is suit for study one pair gear whine noise.For two tones,the frequency and magnitude difference between the two tones is the main factor which affect the human perception.The human hearing system is thought to contain a bank of band-pass filters with over-lapping pass-band.
It should be noted that, all the signals have nearly the same sound pressure level by controlling the signal magnitude an Pure Tone Based on equation(2) and gear noise property, we generated three pure tone noise of 500Hz,3500Hz and 8500Hz, which represent different human hearing sensitivity range.
Specific loudness results of two tones 3500Hz is 400Hz with 3500 Hz in the center.For this case,we generate 3600Hz which is in the bandwidth range of 3500 Hz.Based on equation(3) and gear noise property, we generated four signals with two different frequency components.

Thus it is possible to control and improve the properties of the material by using the orientation effect originated from the textures.
Samples were cut by an electro discharge machine and the surfaces were polished by the mechanical polishing.
In this study, although the origins of the effect of α on recrystallization texture is not clear, there are two factors to be considered to understand the change in the orientation by the α precipitation.
In the case where α precipitation at these preferential sites precedes the recrystallization, the recrystallization behavior is strongly affected by the precipitation in the present alloy.
This is due to the precipitation of α phase; the α phase precipitation strongly affects the recrystallization texture in this alloy.