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Abstract.A common source of noise is operational excitations of mechanical devices, which cause vibrations and thus sound radiation from their surfaces.
Vibration excitation of mechanical devices can cause sound radiation from their surface.
This method can be rather ineffective in the free-field control applications or large enclosures, since it does not affect the origination of sound and thus requires a large number of anti-noise source [1].
Table 1 PiezoelectricCeramic Actuator Specifications Type P5-H Size(mm) Φ60×Φ12×5.5 Resonant frequency Fs(KHz) 28.1 Electro-mechanical coupling factor Kp 0.5524 Resonant impedance FR(Ω) 20 Shunt Capacitance Co (PF) 19.37 piezoelectric constant d33 680 One of the advantages of this PCA is that more force can be provided by cascading multiple piezoelectric ceramic elements, as shown in Fig.2.
Table 1 shows the parameters which represent the PCA properties in this paper.

In this study, the mechanical properties of the material were chosen since that they equivalent to those of low carbon steel with its thickness of 0.2 mm, k = 572 N/mm2, UTS = 391 N/mm2, yield stress = 309 N/mm2 and n = 0.2.
A larger gap could increase a material flow in tangential direction, and a magnitude of tangential stresses, consequently this condition would affect a wrinkling in the flange.
Blank holder force is not being set by close loop control system by considering all the factors that lead to wrinkling and cracking.
Start Initial Blank Holder force Material properties, punch and die dimension, friction coefficient, velocity of punch stroke = 1 mm/s n =1 second Punch stroke to m = velocity x n To calculate radial stress, Deep Drawing force, tangential stress and “Gap” on “m” punch stroke To increase the blank holder force GAP< 130%-180% x Initial thickness of material (<0.26mm) To decrease Blank Holder Force (b) Fd[8] Muammer Gavas, Increasing the drawing height of conical square cups using anti-lock braking system (ABS), Journal of Mechanical Science and Technology 23 page3079~3087, 2009

Workers in nanotechnology may be exposed to new properties of materials and products that have health effects which are not yet fully explored [2, 3].
The approach includes certain additional steps and is part of a comprehensive approach, which has as main objective the control of risk factors [10].
It was clearly highlighted that only measuring the concentration of mass is insufficient to characterize nanoparticles, due to the inability of this parameter to allow forecasting the risks of affecting the health of workers.
In this scenario, if one of the factors considered to have a potentially high risk, work should be carried out in the control level 4.
Huber, Synthesis, properties, and applications of iron nanoparticles, Small, 1, , 482-501, (2005) [4] L.I.

Stress corrosion cracking (SCC) is one of the most important questions about affecting chemical and oil equipment.
Welding residual stress is one of the main factors causing SSCC and SOHIC[5].
(3) In the same parent material under stress corrosion threshold stress intensity factor is greater than the KISCC of HAZ, showing the base metal properties of the sample resistance to SCC than the strength of HAZ.
Chinese Journal of Mechanical Engineering,2007 (9):117-122 [7] BUCHHEIM G M.
Effect of hydrogen environment on the notched tensile properties of T-250 managing steel annealed by laser treatment[J].

This phenomenon will be affected by molding process because of the following factors: uneven thickness of the multi-lumen catheter, the small size of the lumen and the complex cross section.
Its rheological properties are measured respectively by capillary rheometers at temperatures of 190-220 °C.
Rheological properties of different temperatures Temperature[°C] η∞ η0 λ n 190 0 403.711 0.02498 0.41738 195 0 371.397 0.02377 0.42346 200 0 343.974 0.02261 0.42954 205 0 322.804 0.02191 0.43410 210 0 295.234 0.02058 0.44162 215 0 249.560 0.01716 0.45810 220 0 192.518 0.01306 0.47754 The flow of polymer melt was simulated by Polyflow software.
According to theoretical studies, the traction velocity only changes the cross- sectional dimension of the catheter without affecting the cross-sectional shape of the catheter.
Orthogonal experimental factors and levels Factor Level 1 Level 2 Level 3 Level 4 Level 5 Head Temperature[°C] 190 195 200 205 210 Gas Pressure[Pa] 3386 4515 6020 7525 9030 Extrusion Rate[mm/s] 4.5 4.7 4.9 5.1 5.3 Traction Speed[mm/s] 33.83 36.00 38.33 40.50 42.83 The factors of orthogonal experiment were as follows: gas injection pressure, extrusion rate, head temperature and traction speed, and five orthogonal design tables of four levels of five levels were selected, as shown in Table 2.

The design of fiber art can not be separated from the material, the material is an important factor and the material basis for fiber art, which is the central,the soul of designing the fiber art ,the use of materials directly affected the fiber art works.
Therefore, ramie fiber material is a life marked by specific emotional factors, closely related with the creative ideas, becoming the accurate expression of emotion.
Sensory properties of the ramie fiber material.
People get to know the world through the senses to feel, practical experience is a basic element for aesthetic feeling,which can cause some physical pleasure about the specific things, so as to better understand the world.Sensory fiber materials refers to the aesthetic characteristics of the most basic material shown to the people, the physical properties of which is the material itself bringing to the audience's aesthetic experience.
This tends to be more focused on the natural beauty and authentic aesthetic psychology, in modern fiber art, which has attracted more and more attention and recognition from people, many works are cleverly processed, truly reflected the natural beauty of material, showing a kind of nature, which will bring people's aesthetic experience because of properties of the ramie fiber material.

Corrosion fatigue is an issue in military and commercial aircraft, affecting the structural integrity and useful life of an aero structure.
The differences of the FCGRs between the air and corrosive environments are seen to increase gradually, with a decrease of the stress intensity factor range.
The CFCP depends not only upon a mechanical driving force for the cracking, which is quantified by the stress intensity range (ΔK = Kmax–Kmin) and the maximum stress intensity (Kmax or R = Kmin/Kmax)[8], but also upon an environmental driving force[9].
The interaction between corrosion and fatigue reduces the cyclic threshold stress intensity factor range and increases the rate of crack propagation.
Summary Based on detailed mechanical testing and corresponding TEM analysis, we can make the following conclusions: (1) The corrosion environments used in this study have an obvious influence upon the fatigue crack growth rate.

This will be leading to either deposition of the tool material on the substrate surface or alloying near the substrate surface leading to a change in the surface properties of the substrate.
Al and Fe are two metals with a huge difference in physical and thermal properties [7].
It is basically controlled by the extent of heat generation at the interface, heat dissipation to the bulk and the material properties at that temperature.
This is also because no direct equation is available to determine to weld power based on this factor [12].
Though the power consumption is a good indicator of the temperature history of the tool under steady state conditions [14] it neglects other important factors [3].

Introduction Grain size refinement is a well known technique to improve mechanical properties of metallic alloys.
These materials exhibit attractive mechanical properties, in particular high mechanical resistance.
Moreover, if the alloy is partially crystallized after forming, its properties in use can also be modified.
The mechanical properties (i.e.
Compression tests confirm also that the mechanical properties of the glass were not significantly modified by the thermoforming process.

Lightweight aggregate and ordinary aggregate has the different physical and mechanical performance characteristics ,and it is easy that lightweight aggregate floating up and segregating of the concrete, low homogeneity, fast slump loss under the pump pressure or during the transportation.
Thus it can be seen, the lightweight aggregate size, the cement paste viscosity, the contrast between lightweight aggregate density and cement paste density, and all is the important factors on the homogeneity of lightweight aggregate concrete.
At the same time, without affecting pump, enhance the viscosity of concrete as far as possible, on the one hand, reduces the water which would be absorbed by lightweight aggregate, on the other hand, the macroviscosity paste can attached to the lightweight aggregate surface, have seal effect to the lightweight aggregate surface hole, may also reduce the pumping pressure function to concrete, so as to achieve the purpose of reducing slump loss. 4.Preparation the large flow pattern pumping lightweight aggregate concrete According to the above analysis, first of all, according to the actual situation, choose the experimental materials ( table 4-1~ table 4-5).
Wet-density (kg/m3) Slump (mm) Divergence （mm） The description of fresh concrete 28d Strength (MPa) inverted slump time (s) 1 1940 220 580 Low encapsulated property, the lightweight aggregate floated up seriously 50.5 14 2 1930 265 630 Middle encapsulated property，the lightweight aggregate floated up mildly 52.8 8 The strength results of each match ratio can meet the design requirements, but in the big slump situation, all lightweight aggregate flow up at different extent, the first group is the most serious (sees Fig. 4-1), it cannot pump.
Through experiments we can see, that after adjustment of 5# match ratio, the concrete viscosity, encapsulated property, paste fluidity, homogeneity all has improved obviously (Fig. 4-2).