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A material’s sound absorbing properties can be described as a sound absorption coefficient in a particular frequency range.
Porous absorbers are the most commonly used sound absorbing materials, however they do not have good absorption properties at low and mid frequencies.
In order to increase the absorption properties at low and mid frequencies, porous absorber should have larger thickness and size.
As described in the discussion for figure 4 and figure 5, air cavity depth was a main factor that can affect the noise absorption coefficient of perforated plate.
Acoustic Properties of Fibrous Absorbent Material.

Derivation of the system for the Minimum Value Calculation Since there are a great number of different influencing variables affecting the energy consumption, the first step to derive a calculation system is the coverage of all influencing factors.
Analysis of the influencing factors determining the energy consumption.
As a next step, sub-factors can be determined based on the main influencing factors. [4] In this case, the goal is not to find the influencing factors of a problem, but to detect energy drivers of the process.
The term material properties denominates the physical, chemical, and technological properties of a material.
Most of these material properties can be specified quantitive by means of so called material parameters [11].

On the Mutual Interaction between Mechanical Stresses and Internal Corrosion during Isothermal and Cyclic Oxidation of Nickel-Base Superalloys U.
These parameters seem to depend not only on the temperature and the alloy composition but also on the applied mechanical stress.
On the other hand, high-temperature-corrosion attack strongly deteriorates the mechanical properties of Ni-based superalloys.
Once internal corrosion has set in, additional factors have to be taken into consideration: The higher specific volume of the internal precipitates as compared to the substrate causes the generation of residual compressive stresses in the surface layer.
In agreement with Pieraggi [17] it can be concluded that the deteriorating effect of high-temperature corrosion attack (in this case internal nitridation) is not restricted to the corrosion-affected surface layer.

Among the most important parameters of the coatings belong properties such as resistance to oxidation, thermal and abrasion, and good adhesion and tribological properties.
The hard coatings based on (Tix,Al1-x)N prevails with unique properties belong to the most used coatings today.
However, the main factor today which benefits to the life time of cutting tools is deposition of hard and wear resistant coatings.
Nevertheless, a lot of technological variables can affect the final performance such as preparation of the substrate, its chemical composition, grain size, phase distribution, thermal stability, hardness, toughness, etc.
Coating Grade, structure Composition Hardness HV 0.05 [MPa] Maximum working temperature [ºC] Coefficient of friction [-] TINALOX Nanocomposite supernitrid (Ti,Al)N 3500 1000 0.3 HYPERLOX Nanocomposite supernitrid (Ti0.4,Al0.6)N 3700 1100 0.3 Table 2 Nominal physical properties of the tested PVD coatings according to the CemeCon company.

On the other hand, metals are widely used as biomaterials like stents, hip joints and bone plates with a long history, since metals have good mechanical properties, especially toughness, and long terms durability.
If once polymer and metal were bonded and used as a composite material, a new material having good biocompatibility and high mechanical strength could be created.
However, most of research on bonding with silane coupling agent in the dental material field were only investigated about bonding force, and there is few report that examines which factors of the silane coupling agent influences the bonding.
From these experimental, factors that affect on bonding were specified.
Factors governing shear bonding strength between Ti and SPU was thickness of γ-MPS layer.

Three controllable factors of the turning process consisting of cutting speed, depth of cut and feed rate were incorporated.
Introduction Single-response optimization of a process means determining the values of controllable factors that give the highest value of a particular response.
The main mechanical and thermal properties of work material are summarized in Table 1.
Table 1: Mechanical and thermal properties of PEEK CF30 composite Mechanical and thermal properties PEEK CF30 Unit Tensile modulus 7700 MPa Melting temperature 340 °C Density 1.41 g/cm3 Coefficient of thermal expansion for temperature less than 150 °C 25x10-6 m/m/K Coefficient of thermal expansion for temperature exceeding 150 °C 55x10-6 m/m/K Dry turning experiments were carried out on a GORATU G CRONO 4S CNC machine, enabling up to 26.5 kW spindle power and maximum spindle speed 3350 RPM.
Alternatively, when factors are uncontrollable, the overall desirability value can be used to characterize the system based on the multiple selected criteria.

Particularly, we are concerned on how the homogenization technique affects the calculated forming-limit of materials exhibiting qualitative changes in crystallographic texture and hence, evolving anisotropically during the mechanical deformation.
In this sense, each grain is in turn considered to be an ellipsoidal inclusion surrounded by a homogeneous effective medium (HEM) that has the average properties of the polycrystal.
The properties of the HEM are not known in advance because they result from an average of the individual grain behaviors, once convergence is achieved.
In our case, the model is based on the assumption that each grain is surrounded by a homogeneous effective medium that has the average properties of the polycrystal.
We know that many factors influence forming-limit predictions through the M-K approach, the homogenization scheme being one of the most important.

This extent is expected to change with geometry, presence of notches, loading pattern, loading level and material properties.
Thirdly, the stress intensity factors of crack front nodes are calculated (Fig. 3c).
Identification of numerical independent parameters affecting the accuracy of a numerical procedure able to study the fatigue crack growth based on the finite element method.
The main variables affecting the accuracy of the numerical model were identified and optimised.
Stress intensity factors for side-grooved fracture specimens.

However, there is a key factor that need to be taken into cosideration, such as diehole lacation on the multi-hole die.
The optimal die design for such process is to achieve both uniform flow distribution on the outlet cross-section of flow channel and small barus effect on the extrudate so as to ensure the requirements on the extrinsic feature, mechanical property, and dimensional precision of the final products[4].
According to factory experience, the hole diameter dp and the locating circle diameter dc, are two important factors that significantly affect both the forging force and the flow distribution uniform.Therefore, they are selected as two variables for the multi-hole die strcture design.Conversely, the others are considered as constants to reduce the space of optimization algorithm, despite they fairly influence the final extrsion quality.
The deformation load is another important factor contributing to the performance and economics (efficiency and quality) of extrusion forming process.
Wang: China Mechanical Engineering Vol.21 (2010), p.1338

The mechanical properties of the fibers were measured.
The results demonstrate that due to the presence of gelation in the composite fibers, the mechanical properties of the composite fibers increase, and the tensile strength of the composite fibers is also related to gelation content and the degree of deacetylation of chitosan.
Measurements of properties.
The NaOH concentration and the volume ratio of NaOH solution to ethanol are the important factors influencing the coagulation speed of the fibers.
Effect of gelatin content on fiber properties.