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In recent years, a number of technological solutions have been developed for the heat utilization from them.
In a geosystem that uses a large number of vertical rock tubes, they can be arranged in a form that has a hexagonal configuration.
Pre-determine the temperature field of the formed dump, the required number of elements of the heat-exchange system, the capacity of the heat pump installation.
After that, horizontally-directed drilling drills number of wells at the selected level of the formed dump.
Application of fine-grained binding materials in technology of hardening backfill construction.

In the grinding process presented in this paper vitrified CBN wheels with grain size 151 µm and a maximum cutting speed of 125 m/s are used.
The controlled variable is measured and the frequency response (FR) is calculated for a specified number of averages.
In case of the linear axis, the number of averages is limited by its traverse range.
Hence, during the measurement the number of averages must be balanced according to the reference variable’s amplitude and could get inaccurate in lower frequency ranges.
Considering different neglected influence factors such as workpiece geometry, grain size, nozzle type, flowrate and nozzle position, extra effort would be inappropriate.

During the drawing metal is in the conditions of complex non-monotonic loading, which is accompanied by intensive strain-hardening and grain flow creation [13, 14].
However, since the number of drawing passes could reach twenty for achieving true strains (drawing ratio) , then the above theories will give significant errors [23–25], particularly, in the estimation of the acquired mechanical properties of the wire.
Works [27, 28] study the influence of the number of passes, the degree of drawing and other values on standard mechanical characteristics: ultimate tensile strength, yield tensile strength, relative elongation after rupture.
The wire rod material, semi-finished wire and the finished wire product are anisotropic materials with the corresponding developed grain flow.
It should be also noted that this model will provide the best description of the change in mechanical characteristics just for the drawing variant under consideration (characterized by geometrical and design parameters of the die, lubrication conditions, drawing speed, number of passes), because these factors cause effects on the investigated values of the resistance to plastic deformation.

Each unit cell of the tetrahedral and octahedral sites has a number of 64 and 32, respectively, but the cations fill only 8 at the tetrahedral site and 16 at the octahedral site [1,3].
The grain difference between fine sediment and standard chemical lab during the synthesis process can also be a factor in the magnitude of crystalite size with the fine sediment source having a larger magnitude.
The density of CoLa0.1Fe1.9O4 nanoparticles can be obtained from the equation dx=8MNa3, where M is the molecular weight of the nanoparticles, N is Avogadro's number (6.022×1023 mol-1), and a3 is the cell volume of CoLa0.1Fe1.9O4 nanoparticles [30].
Acknowledgements This study was financially supported by Penelitian Dasar Unggulan Perguruan Tinggi (PDUPT) Universitas Sebelas Maret Surakarta contract number: 673.1/UN27.22/PT.01.03/2022.
Wilde, Impurity effect on recrystallization and grain growth in severe plastically deformed copper, Materials Science and Engineering: A. 824 (2021) 141786. doi:10.1016/j.msea.2021.141786

A wide application of magnesium aluminate spinel powder has attracted a number of studies concerning the preparation of magnesium aluminate spinel powder.
However, high temperature calcination leads to grain growth and severe hard agglomeration, which is undesirable for the fabrication of dense magnesium aluminate spinel ceramics.

When these parameters are controlled to reduce the relative diameter of the axial porosity zone, the number of shrinkage defects decreases and the quality of large diameter rolled steel becomes better.
All of the above methods reduce chemical and structural heterogeneity, provide a finer grain structure, improve the mechanical properties of the concast slab and rolled stock.

Although the networks have many types, they consist of a large number of neurons that are widely interconnected to constitute a parallel processing network.
Each layer includes a number of neurons and is sequentially connected.
As long as the number of neurons and the training samples are enough, the “black box” is able to predict the output for any input.
The network was trained by dynamical adjustment method to determine the node number of the hidden layer.
Hiremath, “Classification of cast iron based on graphite grain morphology using neural network approach,” Proc. of SPIE, vol. 7546, pp.

Figure.1:Nigeria map Showing Obajana the study area N Figure. 3: Topographic Map of Obajana and environs Figure. 4: Excavated Surface of Obajana Limestone Geology of the Deposit: The deposit is a coarse grained grey crystalline limestone.
According to [19], the required numbers of discontinuities to be mapped are 20 for orientation of the set, 50 – 100 for characterization.
The maximum declination of the mean plane of the discontinuity was measured with the clinometer (dip) and expressed in degrees as a two digit number from (000-900) e.g 030 or 880 (c) The azimuth of the dip (dip direction) was measured in degrees counted clockwise from the true North and expressed as a three digit number e.g. 0350 or 2870 (0000-3600) (d) The dip and dip direction were recorded in this order with two digit and three digit numbers separated by a line e.g. 880/2870.
The pair of numbers represents the dip vector.
(f) A total number of 115 readings were taken as specified by [18] i.e (50-300 readings) and 50 readingswere used for analysis in this paper.

In this type of the forming, the material is strengthened and a texture is formed, which means that grains are elongated in the direction of the applied force.
Total number of elements for the whole assembly was just over 250,000 pieces.
The number of steps in the second operation was 200 with the write interval of each 10. step and the step increment was 0.5 mm/step.
The number of steps, the write interval, and the increment are the same as in the second operation, but the calculation stops when the distance between the dies reaches 10.5 mm. 10.
In Fig. 6 can be seen the temperature field of the first operation for the step number 1.

Figure 1 Age Hardening Process In the early stages of aging, a large number of very small clusters of the secondary Ө-phase are formed.
Positron annihilation has been intensively studied in metals and the reason for this is that the positron annihilation method makes it possible to determine such important characteristics of metals as the electron momentum distribution, the Fermi energy (usually measured in eV), the number of free electrons per metal atom, and the concentration of such electrons in the conduction band.
Firstly, we quenched it at 520oC and then aged it at two different temperatures (150 or 175oC) as seen in figures 4 and 5. 0 2 4 6 8 10 12 14 16 18 0 5 10 15 20 25 30 Anneling at(150) hardness(1050) lifetime(1050) Figure 1 Aging time (hour) after quenching at (520) Hv (number) 120 130 140 150 160 170 180 190 200 210 220 mean lifetime(ps) 0 2 4 6 8 10 12 14 16 18 0 5 10 15 20 25 30 Annealing at(150) Hardness(1050) Mean lifetime(1050) Figure 3 Aging time (hour) after quenching at (530) Hv (number) 120 130 140 150 160 170 180 190 200 210 220 Mean lifetime (ps) 0 2 4 6 8 10 12 14 16 18 10 20 30 40 50 60 70 anneling at(175) Hardness(6063) lifetime(6063) Figure 5 Aging time (hour) after quenching at (520) Hv 170 180 190 200 210 mean lifetime(ps) In Fig.4, the samples (6063) were quenched from 520oC into distilled water and then annealed at 150oC for various times.
-2 0 2 4 6 8 10 12 14 16 18 10 15 20 25 hardness(6063) lifetime(6063) Figure 4 Aging time (hour) after anneling at (520) Hv 170 180 190 200 210 Anneling at(150) 0 2 4 6 8 10 12 14 16 18 0 5 10 15 20 25 30 35 40 45 50 55 60 Annealing at (175) Hardness(6063) Lifetime(6063) Figure 6 Aging time(hour)after quenching at(530) Hv (number) 150 160 170 180 190 200 210 220 Mean lifetime (ps) 0 2 4 6 8 10 12 14 16 18 0 5 10 15 20 25 30 35 40 45 50 55 60 Hardness(6063) mean lifetime(6063) Figure 7 Aging time(hour)after quenching at(530) Hv (number) 150 160 170 180 190 200 210 220 Annealing at (150) Mean lifetime (ps) Firstly, the lifetime increased to a maximum value after 4 h of annealing at 175o C , and then decreased to a stable value for all subsequent annealing times.
Somoza: Acta Materialia, 52 (2004) 4707-4726 [8] Zhao Y.H., Liao X.Z., Valiev R.Z. and Zhu Y.T., Enhanced Mechanical Properties in Ultrafine Grained 7075 Al Alloy, Journal of Materials Research, 20[2] (2005) 288-291 [9] Kulkarni A.J., Krishnamurthy K., Deshmukh S.P. and Mishra R.S., Effect of Particle Size Distribution on Strength of Precipitation-Hardened Alloys, Journal of Materials Research, 19[9] (2004) 2765-2773 [10] Lumley R.N., Polmear I.J. and Morton A.J., Control of Secondary Precipitation to Improve the Performance of Aluminum Alloys, Materials Science Forum, 396-402 (2002) 893-898 [11] Eskin D.G., Hardening and Precipitation in the Al-Cu-Mg-Si Alloying System, Materials Science Forum, 396-402 (2002) 1037-1042 [12] Cheng L.M., Poole W.J., Embury J.D. and Lloyd D.J., The Influence of Precipitation on the Work-hardening Behaviour of the Aluminum alloys AA6611 and AA7030, Metallurgical and Materials Transactions A, 34 (2003) 2473-2481 [13] Schiffmann R.