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During the process of multiresolution analysis of the signals, the wavelet coefficients of the useful signals and the wavelet coefficients of the noises have different properties on different scales, which are used to distinguish the useful signals and noises.
The result of the wavelet threshold denoising method is mainly related with the following three factors: the number of the decomposition scales, the choice of the wavelet function and the choice of the threshold function.
The denoising result is affected by the number of the decomposition scales greatly.
The denoising result is affected by the choice of the wavelet function greatly to some extent.
After analyzed the three affecting factors, the factors of wavelet threshold denoised method are confirmed.

Introduction of experiment Raw material:Cement: P. Ⅱ52.5 Portland Cement made in a cement plant in Nanjing, its basic physical and mechanical properties and chemical composition are shown in table 1 and 2, the content (mass fraction) of C3S, C2S, C4A and C4AF in its clinker is 55.5%, 19.1%, 6.6% and 10.2% respectively.
Table 1: Physical and mechanical properties of Portland cement Fineness Specific surface (m2/kg-1) Setting time(min) Compressive strength(MPa) Split strength(MPa) Normal consistency Water requirement (% Slot plate screens Initial setting Final setting 3d 28d 3d 28d 26 0.3 341 103 159 35.4 65.2 6.4 9.2 Table 2: Chemical content of main gelled materials (%) Gelled material SiO2 Al2O3 CaO MgO SO2 Fe2O3 Na2O K2O Ignition loss Cement 20.60 5.03 65.06 0.56 2.24 4.39 1.31 Silica fume 93.20 0.51 0.51 0.23 5.56 Fly ash 52.38 32.12 2.16 0.47 .033 4.12 0.26 0.60 1.31 Slag 33.49 12.20 36.34 1060 0.67 1.30 .034 2.17 1.27 Sand: Yellow sand made in Nanjing, its apparent density is 2500kg／m3, bulk density l615kg／m3, slit content 1.0% and fineness modulus 2.72 and it belongs to Ⅱmedium sand.
Engineering Properties of Poly Carboxylic Concrete Air-entraining Agent [J].
The Study of Factors Affecting Air Content of Concrete [J].
SJ-2 New Air-entraining Agent and Its Air-entraining Concrete Properties [J].

Under different crystallization time, grain size distribution of the synthetic product According to the above analysis, the factors affecting the synthesis of analcime optimum technological parameters are: silica alumina ratio SiO2, Al2O3 is 50, stirring time is 6 h, aging time of 24 h, the crystallization temperature is 120 ℃, crystallization time is 15 h.
In the synthesis of zeolite, not only by the stirring time, aging time, the influence of crystallization temperature and time, also affected by other factors.
Under existing experimental conditions, taking into account the above factors on the influence of the crystallization products, and through X-ray diffraction (XRD) and FM-300 microscopy to the characterization of products.
Through the analysis of front can draw the following conclusions: 1）a long time formed by the mixing of zeolite molecular sieve grain size is small, has the trend of membrane; 2) the crystallization temperature and time have a great effect for the synthesis of zeolite, and two factors often appear interaction; 3) aging time effect is not big, aging time on the role of zeolite synthesis mechanism needs further research.
The Synthesis and Properties of Microsize NaY Zeolite.

In a mechanical system that has periodically repeated subcomponents, premature failures or malfunctions often occur.
The rate of decay, known as localization factor by Hodges and Woodhouse [4], is employed to investigate localization phenomena (see Refs. [5, 6]).
The probability variations versus the statistical properties of the parameters are calculated through Monte Carlo simulation.
In the following, effects of some statistical parameter properties along with the number of subcomponents on the probability of frequency response localization will be discussed.
Conclusion The effects of statistical properties of the natural frequency, the coupling stiffness and the damping ratio of a periodic system on the strength of frequency response localization are investigated.

The quality of mixing rubber not only affects the process workability of tread glue, but also determines the quality of finished tires.
The experiment details are as below. 1 Experiment 1.1 Experiment Method This experiment adopts the orthogonal experiment method, while taking into consideration of the effects of several factors on the single step mixing at low temperature mixing, different factors are selected at different levels.
Therefore, by the minimal experiments, the best match of the factor levels and which factor has the most influence on the single step mixing at low temperature are determined.
The experiment factors in this experiment are four: the rotor speed, the internal mixing time, the mill’s temperature, the open mixing time, with each factor are selected at four levels respectively.
In this way, the experiment scheme is determined and 16 experiments are conducted. 1.2 Materials Natural rubber, N330, Silica, ZnO, SA, Si-69, PlasticizerA, RD, 6PPD, NOBS, Sulfur，all the rubber formulas are commercially available. 1.3 Main Instruments X（S）M—1.7 Experiment Mixer, one, made in China; X（S）K—160Open mill, one, made in China, QLB—400×400×2 Vulcanizing machine, one, made in China; Mooney Viscometer, made in Taiwan Yuken; Electronic tensile testing machine, made in Taiwan Yuken. 1.4 Test Characterization The test of mechanical properties of Vulcanizates (tensile strength, tear strength and Elongation at break, etc.), determined under GB/T528-92, Dumbbell specimen,tensile speed 500mm/min, temperature 20℃, test with TS 2005 b Universal Testing Machine. 2 Results and Discussion 2.1 Data Process.

Mechanical properties such as tensile and flexural strength and modulus, as well as impact resistance, however, did not exhibit significant improvements, which might also be affected by the variability in the natural fibers and the hand lay-up method.
Statistical analysis of the mechanical properties was carried out by one-way analysis of variance (ANOVA).
Mechanical Properties of the Nito Fiber-Epoxy Composite.
Figure 2 presents the dried Nito fibers, the fabricated Nito fiber/epoxy composite test specimens, and a summary of their corresponding mechanical properties.
The hand lay-up fabrication technique may also contribute to this variability, as it can influence factors such as fiber wetting, void formation, and the occurrence of delamination [14].

The load-bearing skins of such structures are predominantly manufactured from polymer composite materials (PCM), which exhibit excellent mechanical properties, high corrosion resistance, and the ability to withstand substantial operational loads [3, 4, 5].
Although these defects can be mitigated through technological interventions during the assembly of sandwich structures, the corrective processes inevitably induce residual stresses in the affected areas, which adversely impact the mechanical performance of the component [12, 13].
Most studies focus either on general mechanical properties or on modelling specific defect types without defining acceptable defect dimensions.
Thus, the critical factors determining the permissible limit for a waviness-type defect are either the maximum normal stresses at the cross-section point or the maximum shear stresses at critical cross-section .
Kondratiev, Elastic properties of steel-cord rubber conveyor belt, Exp.

Because titanium alloy has a lot of excellent properties, e.g. smaller density, higher specific strength, corrosion resistance and so on, it is widely used for making important engine thin-walled parts [1].
Many scholars engaged in the research of factors including cutting property, machining parameter, tool parameter and fixture [2-9], and obtained some achievements, but the research achievements in the field of experimental machining involved in precision cutting titanium alloy thin-walled parts is still fewer.
The vacuum cups fixture is used to prevent distortion and fixture stress from affecting the precision machining experiment.
In this study, in order to reduce deformation of workpiece and obtain a better surface quality in cutting process, three machining parameters are selected as controlled factors.
In this paper, the main factors affecting the objective function are only cutting speed, feed rate and cutting depth, so the objective function is given as: (2) where vc, f and ap are the design variables, Q is the material removal volume per unit time.

The symmetricity in the crack initiation at the counter side of stress concentration is severely affected by the loading pattern [6].
The material property of the laminate corresponds to a woven GFRP impregnated with epoxy resin, shown in Table 1.
Mechanical properties of GFRP laminate.
The subsequent significant failure observed was circular notches, and the square notches were comparatively less affected.
[7] ASTM D3039/D3039M-17 (2017) Standard test method for tensile properties of polymer matrix composite materials.

Therefore, the temperature is an important factor in the molding of biomass.
Considering many factors affect the accuracy of extrusion process, it is necessary to simplify the model appropriate treatment, and makes the following assumptions: (a) the initial straw materials room temperature is (20℃); (b) The thermal conductivity of air is small, ignoring convection; (c) Ignore the internal chemical changes in straw.
And thermal analysis directly related to the material properties includes: thermal conductivity, heat capacity, enthalpy, heat transfer coefficient, emissivity, heat rate.
The equation is: (1) The physical properties of the material parameters from the material is in Table 1.
Table 1 Thermophysical properties of materials Temperature[℃] Thermal conductivity [W/(m·℃)] Enthalpy [J/m3] 0 0.0025 55 50 0.006 100 100 0.012 130.2 150 0.016 162 200 0.014 200 Unit selection and meshing.