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In this paper we make full use of the advantages of FA and the properties of Elman neural network structures to establish FA-Elman algorithm.
It is also necessary to analyze and extract useful characteristics of variables from large quantities of data and eliminates the influence of relevant and repeated factors, so as to reduce as many feature dimensions of the samples as possible without affecting solving the problems.
But application of this kind is not common in Elman neural network, people like Yan Weiguo proposed a method of modeling based on PCA and Elman network to evaluate the quality of mechanical products and apply it in predicting mechanical properties of cold-rolled ribbed steel wires and bars[9].
We analyze the sample data by PCA and FA, respectively, Exact 16 principal components and 16 factors from the case, take scores of the principal components or factors as the inputs of the network and establish a new Elman neural network.
Quality modeling of mechanical product based on PCA and Elman neural network.

Mechanical Properties and Creep Behavior of Carbon Fiber Nano-Composites Yi-Luen Li1,a, Wei-Jen Chen1, b, Ming-Yuan Shen1, c, Chin-Lung Chiang2, d and Ming-Chuen Yip*,1,e 1 Department of Power Mechanical Engineering, National Tsing Hua University, Hsin-Chu, Taiwan 2 Department of Safety, Health and Environmental Engineering, Hung-Kuang University, Taichung, Taiwan ad550309@yahoo.com.te, bd937716@oz.nthu.edu.tw, chbj678@seed.net.tw, ddragon@sunrise.hk.edu.tw, emcyip@pme.nthu.edu.tw Keywords: Carbon nanotube, Electrical conductivity, Mechanical properties Abstract.
Recently, it has been observed that surface modification of carbon nanotubes（CNTs）influences on CNT’s distribution among epoxy resin and affects the mechanical properties and electrical conductivities of CNTs.
Owing to above-mentioned effects, carbon nanotubes treated with oxidizing in organic acids, a kind of surface modification, generates functional groups on the surface of CNTs taht is a major investigation in this study to enhance mechanical properties and electrical conductivities of CNTs.
The influence of the different proportion contents of CNTs added into epoxy resin on mechanical properties and electrical conductivities of composites was investigated, and strength of material tested under different temperature environments was observed.
From the test results and comparisons of creep behavior between CF/epoxy and CNT/CF/epoxy resin laminates tested under various circumstances, loading, temperature and humidity can be regarded as the crucial factors to influence on the creep behavior.

Dittrich[11] studied the quenching and partitioning heat treatment of experimental steel 42SiCr, the evolution of microstructure and hardness of heat affected zone (HAZ) of 42SiCr weld and its main influencing factors.
The effects of laser power and welding speed on the mechanical properties of TWBs were studied.
The joint of 35 J / mm had the best comprehensive mechanical properties.
The welded joint had the best mechanical properties under this parameter condition.
Peng, Microstructure and mechanical properties of fiber laser welded QP980 steel, J.

With the introduction of a mass transport mechanism the entire problem is subjected to a time frame that dictates the time-dependent action of soluted species on mechanical properties.
The simulation of showcases demonstrates crack initiation and crack propagation aiming for the determination of stress-intensity factors and crack-resistance curves.
Finite-element calculations take those mechanisms into account by mass transport simulations and coupling of the local hydrogen concentration to material strength and toughness properties, e.g.
Additional material degradation is superimposed by the local concentration acting on the plastic properties of ψ0m,p.
The mechanical properties were set to E = 210GPa and ν = 0.3, the critical energy release rate was assumed as GC = 10.83kJ/m2.

Structural State, Phase Composition and Mechanical Properties of Wear-resistant Cast Iron Modified by Ultrafine Powders Anna P.
The paper explores the effect of a modifier based on ultrafine powders of refractory metal oxides on the change of structural state, phase composition and mechanical properties of cast iron of ИЧХ28Н2 (Russian grade).
It is known that metal cooling is often accompanied by the formation of a coarse-crystalline structure from a liquid state, which has a negative impact on castings mechanical properties.
However, the selection of ultrafine powder-based modifiers as applied to specific material and mechanisms of affecting the material structure and properties change are to be further studied.
The corrosion properties of the wearproof cast iron samples were investigated.

The formation of quality indicators at the stage of mechanical processing requires a deep analysis, which allows us to identify the factors that have the greatest impact on the roughness and accuracy of the shape of the surfaces of precision machine parts during their manufacture.
The formed local metastable layer on the surface of the workpiece differs in its mechanical properties from the main part of the material, which at the intersection with the cutting plane will lead to an instant change in the stress-strain state in the chip formation zone, affecting the properties of the closed potentially self-oscillating technological system and thus dynamically stabilizing the machining process.
The local zone, with its distorted crystal lattice and mechanical properties different from the main metal volume, causes an instant change in the stress-strain state in the chip formation zone.
When the cutting plane intersects with the local heat-affected line, the chip angle changes due to the difference in dissipative properties of the main material of the workpiece to be machined and the material in the local impact zone.
Fig. 3 The process of applying local thermal impact: 1 - contactors - devices for applying a local thermal effects; 2 - workpiece (material – steel 45); 3 - tool holder; 4 – device for applying local thermal effect Firstly, the treated surface will have local areas with other physical and mechanical properties than the material of the workpiece, which will have a negative impact on the operational properties of the part.

Mechanical properties are focused on determining stress-strain curves for each characteristic weld region.
While establishing the welding procedure for HSS grades, it is very important to determine the correct welding parameters that leads to least degradation of mechanical properties in Heat Affected Zone (HAZ).
The HAZ can be further divided into several characteristic regions with different microstructures and mechanical properties.
Optical micrographs Mechanical Properties.
Bettayeb, Effects of martensite-austenite constituents on mechanical properties of heat affected zone in high strength pipeline steels-review, Chemical Engineering Transactions 70 (2018), 583-588. doi: 10.3303/CET1870098 [7] D.

The effect of various process factors is analyzed by the simulation of the rolling process and based on visual analysis of the simulation result, the primary and secondary factors affecting the relative density and the rolling force are obtained.
Zhou[5] comprehensively introduced the principle, usage, method and process parameters of metal powder rolling, and analyzed the main factors affecting the rolled-piece performance.
Table 2 Process parameters for simulations of rolling compaction The parameters of rolling roll diameter D 100 150 180 compressibility 84 82 80 rotational speed of roller (rad/s) 0.42 0.35 0.3 friction coefficients 0.4 0.35 0.3 Table 3 Results of the orthogonal experiments for simulation Arrangements of experiments The result of simulation Factors Maximum of Rolling force (N) Minimum of Relative density 1 84% 0.3 0.3 100 15752 0.841 2 84% 0.35 0.35 150 38203.2 0.922 3 84％ 0.42 0.4 180 51977.7 0.970 4 82％ 0.3 0.35 180 34344.6 0.918 5 82％ 0.35 0.4 100 20774.8 0.871 6 82％ 0.42 0.3 150 26036.7 0.883 7 80％ 0.3 0.4 150 26532.2 0.881 8 80％ 0.35 0.3 180 31745.5 0.866 9 80％ 0.42 0.35 100 15530.6 0.830 The analysis of process parameters in powder rolling.Based the above analysis, the main factors affecting metal powder rolling are physical and mechanical properties of powder materials and the process parameters.
The sequence of factor affecting on the relative density and the rolling force is: >>>.
[4] Simon O,Guigon P.Correlation Between Powder-packing Properties and Roll Press Compact Heterogeneity[J].Powder Technology,2003,130(1):257-264

Mechanical properties of recycled concrete aggregates could be improved by adding activated water instead of ordinary water.
There are many different factors such as the kinds and amounts of alkali and the water slag ratio affecting the compressive strength of recycle geopolymer.
Particles with poor mechanical properties, such as needle flake or sundries, are took out when using as recycled aggregates in the experiment.
There are different factors which impact the compressive strength of recycled geolymer.
There are many different factors that affect the compressive strength, the sort and the content of alkali, the modulus of sodium silicate and the water slag ratio.

In dissimilar weld joints, the mechanical properties changes vary sharply and from fusion zone to base materials [7].
These changes can be strongly influenced by the properties of heat affected zone HAZ and alloying elements distribution throughout weld joint.
Moreover, during the investigation of hybrid welding parameters of low alloy steel [13], it has been found that welding current provided the main factor affecting mechanical properties of hardness and tensile strength.
Then, the mean S/N ratios at each level for various factors and the optimal level (the largest S/N ratio among all levels of the factors) could be calculated.
There are therefore eight degrees of freedom of the three factors.