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In the course of the theoretical analysis and the experimental studies of process of the magnetic-pulse welding preforming (MPWP), the parameters influencing quality of welded connection are detected: working voltage of U charges of capacitor banks, capacity of the accumulative unit C of the equipment, inductivity of the working tool – the inductor L, N determined by number of rounds.
Mode of processing and parameters of the equipment: tension on the drive U=2kB, battery capacity of C=150 condensers of microfarad, number of rounds of the inductor N=4r.
Drive C capacity, working voltage of U and number of rounds of the inductor N – value the defining frequencies of f and amplitude of a jolt of electricity were variable parameters in determination of the optimum modes of magnetic-pulse welding preformation.
For different experimental samples they have the following values: capacity of the drive is C=150÷450 of microfarad; charging voltage of U=1÷2,5 kV; number of rounds of the inductor N = 4÷12r.
Fig. 4 Dependences of effort upon a rupture of P aluminum alloys а - from value of the overlap Δ; b - from value of the gap h Metallographic researches of a zone of connection have not revealed formation of the general grains, fig. 5.

The primary particles had grown to ~1 µm and they had edged shape and rugged surface probably due to the grain growth of the primary particles as shown in Fig. 3(c).
Fig. 5 shows the capacity vs. cycle number for the heat-treated electrodes between 3.0 ~ 4.5 V and 3.0 ~ 4.6 V at a specific current of 140 mA/g.
It suggests that the shape and surface morphology should be one important factor for the electrochemical performance besides the particle size. 0 5 10 15 20 25 30 0 20 40 60 80 100 120 140 160 180 200 220 Charge/Discharge (mAh/g) Cycle number 900o C charge 900o C discharge 1000 o C charge 1000 o C discharge 0 1020304050 0 20 40 60 80 100 120 140 160 180 200 220 Charge/Discharge (mAh/g) Cycle number 900o C charge 900o C discharge 1000 o C charge 1000 o C discharge (a) (b) Fig. 5.
Acknowledgements This work has been funded by the KIST program under contract number 2E18630.

The average grain size and its shape coefficient were evaluated using an optical microscope with an image analyzer integrated to personal computer with Image-Pro Plus software.
Moreover, the number of nuclei was increased significantly with the decreasing of molten temperature, which making the primary crystals were developed from dendrite to uniform, fine and near spherical directions.
Just because of this, when the rod insertion temperature was reduced to 615℃, although the stirring time was the shortest, the primary crystal was evenly distributed across the whole sectional area because of the formation of a large number of nuclei at this time.
In the time interval from rod insertion end to quenching, the molten metal with a large number of nucleation was cooled slowly at the speed of 13.2~14.5℃/min between liquidus and solidus, It has been found that the primary crystals size was increased with increasing of the time interval.
Under the function of super-cooling and longer stirring, larger number of nuclei may restrict the growth of individual crystals leading to the most ideal semisolid slurry. 100μm 100μm 100μm (a) Raw material (b) Ex.1 (c) Ex.2 100μm 100μm 100μm 100μm 100μm 100μm (d) Ex.3 (e) Ex.4 (f) Ex.5 100μm 100μm 100μm (g) Ex.6 (h) Ex.7 (i) Ex.8 Fig.3 The microstructure of A356 alloy under different experiments Figure (i) showed the result of Ex.8 in which SUS303 stainless steel was used as the stirring rod.

At the same time, a number of materials of natural and technogenic origin, which are an effective substitute for quartz sand, are known.
The calculation was carried out in relation to the foam concrete matrix with the following component consumption for 1 m3: Portland cement grade PTs400-DO - 227 kg; tuff sand with the largest grain diameter of 1.25 mm - 227 kg; water - 195 kg (B / T = 0.43); foaming agent “Neopor 400” - 1.25 kg.
It was also noted that with an increase in the number of introduced fibers, the average pore size increases (indicator ).
At low percent saturation ( = 0,20 %) the decline leads to an increase in the average pore size, which is explained by a decrease in the number of contacts (interactions) between the fibers and a decrease in the ability to the disperse large pores.
Summary It can be concluded that the introduction of a sufficient number of short fibers into the foam concrete matrix leads to the material’s hardening, which is ensured not only by the reinforcing properties of the fibers, but also by their ability to positively affect the structure of cellular concrete.

Every component's microstructure was discovered to be consistent, with grain sizes up to 5-grade.
Based on the above proposed objective function and according to a large number of simulation data and actual production experience, in the case of titanium alloy head ACDR forming load is minimum, the uniformity of metal flow and the uniformity of thermal parameter distribution should be improved as much as possible.
The primary α-phase, which makes up around 30% of the total, is distributed fairly uniformly and has a grade 5 grain size.
Mechanical properties of each direction after deformation Number- Direction Yield strength Rm/MPa Fracture strength Rp0.2/MPa Elongation A/% Shrinkage Z/% Standard ≥1030 ≥885 ≥8 ≥23 01-T 1135 985 16 47 02-T 1128 970 16 45 03-R 1135 986 15 47 04-R 1140 976 15 49 05-A 1132 980 16 48 06-A 1131 977 15.5 48 Uniformity 0.33% 0.56% 2.88% 2.63% 5.
The distribution of the primary α phase is relatively homogeneous and accounts for about 30%, which corresponds to a grade 5 grain size.

The productive practice of endless strip production (ESP) showed that the longest number of continuous casting furnace reached to 15 heats (4500 tons), the longest rolling length in single casting period was 182 km, the qualified rate of products was up to 99.73%, the yield rate was up to 97.51% and the thin strip ratio had a maximum value of 40.57%.
In 2017, the average casting speed of ESP was over 5.5 m/min, the monthly average number of continuous casting furnace reached to 10.2, and the highest number was up to 12 with about 3640 tons [6].
But at present, the maximum number of continuous casting furnace was 15.
The product performance was very stable, the fluctuation of strength was below 10MPa and the fluctuation of elongation was lower than 1.5%, while the grain grade of ferrite was 12 and the area percentage of martensite was 30-35%.
The achievements of endless continuous casting process included that the average monthly number of continuous casting furnace reached to 10.2 in 2017 and now the longest number of continuous casting furnace reached to 15. 2.

In this context, directionally solidified (DS) as well as single crystal (SX) nickel superalloys were developed for achieving an improved fatigue resistance and a significantly increased creep rupture strength by eliminating grain boundaries [1].
This has led to local stress and local strain approaches based on the Basquin equation and the Coffin Manson equation [4] and . ( 1 ) Thereby, the symbol Ni denotes the number of load cycles related to a suitable end-of-life criterion.
The relation ∆σ => Ni then forms a surface of equal number of cycles-to-failure.
Obviously, for the uniaxial load ∆σd in either of the characteristic directions both, the general multiaxial approach of Eq ( 3 ) and the uniaxial formulation ( 2 ) have to predict the same number of cycles-to-failure, i.e. , where ∆σd denotes the stress tensor components produced by ∆σd.
After iteration for the Hill parameters, the number of cycles-to-failure is determined by where the Hill function is defined according to Eq ( 4 ).

It has been documented that ECP can be used to improve the properties of the metallic materials, including refining grain size, improving chemistry homogeneity and eliminating defect.
Compare with the XRD spectra of hypoeutectic Fe-C alloys without ECP, the number of cementite peak decrease, the intensity of ferrite peak increase and generate graphite peak after ECP treatment.
This phenomenon can produce a large number of free carbon atoms.
And graphite nucleation near the dislocation pile-up doesn’t need the diffusion of substituted atom to vacate space and decrease the driving force of phase transformation of graphite, so the increasing number of dislocation pile-up which around cementite is benefit to graphite nucleation.
When the temperature below the eutectoid temperature, austenite area becomes carbon-depleted region because of large numbers of graphite formation.

It is generally acknowledged that the main stress brought by wire ropes bending-over-sheaves is tensile stress, bending stress and extrusion stress. 1) Tensile stress The tensile stress of wire rope can be calculated approximately is expressed as (1) Where is the axial load of rope, is the number of wires, is the diameter of wires and is the lay angle of the strand in rope. 2) Bending stress The researchers such as Ridge [8] from University of Reading have done research about the measuring and theoretical calculating of bending stress of wire ropes, the formula for calculating bending stress of wire is given by (2) Where is the initial radius of curvature, is the radius when on the sheave and is the elastic modulus of wires.
Formula for calculating extrusion stress of the contact point between wire and the groove is expressed as (5) Where , is the elastic modulus of groove, is the number of outer wires and is the curvature of contact point. 3.
The effective bearing area of the wire cross-section is reduced due to wear and deformation, and the local stress becomes larger, micro cracks appear on the grains of wire surface.
With the increase of number of bending, cracks continue to expand, the effective bearing area of wire cross-section is becoming smaller while the local stress is becoming larger, once the remaining wire cross section is no longer able to carry the load, the wire will break.
With increasing of number of bending, the damage will have a great influence on fatigue failure. 5.

In the presence of hundreds or thousands of features, it is common that a large number of features are not informative because they are either irrelevant or redundant with respect to the target concept [2].
Theoretically, the optimal feature selection requires an exponentially large search space (O(2m), where m is the number of features) [1].
As the category information of rare classes is not adequate, only the most common 10 categories are used in our experiments, which are Earn, Acq, Money-fx, Grain, Crude, Trade, Interest, Wheat, Ship and Corn.
We preprocess the data in a formal way: all numbers and stopwords are removed, words are converted into lowercase, word stemming is performed using the Porter stemmer, some noisy words are removed.
The parameter of selected feature number has great influence on the performance comparison.