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Introduction In situ stress is one of the most principal and basic factors causing the deformation and failure of the surrounding rock mass and support, as well as the dynamic disasters in mining engineering [1,2].
All the factors influencing the mining stability should be investigated and analyzed comprehensively and in detail at first for the reasonable mining design and construction.
The design with rational technology, safe construction and higher economic profit cannot be guaranteed without mastering these factors with calculations and analysis [4].
(Fig.3) Layout of the Measuring Points In situ stress measurement is influenced by many factors, and the selection of the right measuring points is the most important one.
Rock mechanical parameters Table 1 showed the rock mechanical properties of rock cores measured in lab as lack of field experiment systems.

Materials The research used 3 mm-thick polymethyl methacrylate (PMMA) commonly called acrylic as shown in fig 2, meanwhile the properties of polymethyl methacrylate material can be seen in table 1.
Polymethyl methacrylate properties [5] Young modulus (GPa) 3,2 Tensile strength (MPa) 35 – 62 Elongation (%) 5 – 70 Compressive strength (MPa) 28 -97 Yield strength (MPa) 48 – 97 Thermal expansion (e-6/°C) 48 – 80 Thermal conductivity (W/m.
The measurement indicated that the cutting speed affected the gap width made which all cutting with 6-10 mm laser head distance.
The other factor which contributed to the gap width was the wind blowing from the side of the machine that spread the laser beam onto the specimen.
Besides, the engine vibration during operation also affected the difference in the resulted gap width.

That is why grey cast iron is generally used to make these units, as it has high hardness and good casting properties.
These factors make machining of such pieces quite a difficult task [1–3].
These factors directly affect the durability and accuracy of the whole machine-tool.
The use of oxide-carbide ceramics is characterized by significant differences in comparison with the use of other cutting materials (including hard alloy), primarily due to physical and mechanical properties.
Logutenkova, Dependence of physical and mechanical properties of metal surfaces on microgeometric parameters, IOP Conference Series: Materials Science and Engineering 483(1) (2019) 012045

Recent study revealed that the process becomes complex and non-linear system as a result of multiple independent variables affecting GPG extraction process [14].
Simulation study was conducted at ANFIS optimum setting for predicting GPG yield based on the optimum factors in Table 6.
Okafor, The rheological properties of grewia gum, Nigeria Journal of Polymer Science and Technology, 2(2001) 169-175
Kunle, Effect of Grewia gum on the mechanical properties of Paracetamol tablet formulations, Afr J Pharm Pharmacol., 2 (2008) 1-6
Musa, K.Y Musa, Compression, mechanical and release properties of paracetamol tablets containing acid treated Grewia gum, J Pharm Sci Technol., 1 (2009) 74

Tribological properties of coatings were carried out using a pin-on-ring tribometer at room temperature and 500˚C, respectively.
The objective is for the properties of both materials to be manifested in their respective temperature ranges.
Alkali fluorides (CaF2, BaF2, LiF2) is an alternative choice for their low shear strength and stable thermophysical and thermochemical properties at elevated temperature [3].
Fig 4: Microhardness of Ni60A-CaF2-WS2 coatings Fig 5: The relationship between bonding strength and spraying process Adhesive strength is one of the most important factors in thermal spray coating since it directly relates to the durability of the coating.
The friction coefficient of coatings was in the rage of 0.25~0.35 at ambient temperature and 0.45 at 500˚C with good wear properties and high adhesive strength.

Introduction Carbon Fiber Reinforced Plastic (CFRP) usage in the aerospace industry has been steadily increasing due to its superior material properties such as the high strength-to-weight ratio, high stiffness-to-weight ratio, high corrosion resistance, and low thermal expansion coefficient.
The surface roughness Ra is one of the most important factors to evaluate the surface quality.
Variation in the surface quality depends on the condition of cutting edge and the property the coating.
For Tool B and Tool C, it appears that coating is a main factor in decreasing of the cutting force.
El-Hofy, Factors affecting workpiece surface integrity in slotting of CFRP, 1st CIRP Conference on Surface Integrity (CSI), Procedia Engineering.Vol.19(2011) ,p. 94

The increased density of concrete with curing time can be attributed to several factors: 1-Formation of Hydration Products. 2- Reduced Porosity. 3- Strength Gain These results are in Table 2 and Fig. 4.
· It can produce ultra-high strength concrete with excellent mechanical properties using locally available materials to create an economically viable RPC.
Karabulut, “Mechanical properties of reactive powder concrete containing mineral admixtures under different curing regimes,” Constr.
Khalil, “Some properties of modified reactive powder concrete,” J.
Collepardi, “Mechanical properties of modified reactive powder concrete,” ACI Spec.

Some physical and mechanical properties of OPC concretes or mortars with waste PET aggregates are examined in the studies [6-8].
Its chemical properties are shown in Table 1.
The chemical properties are shown in Table 1.
The consequence is progressive leaching of portlandite and C–S–H, thus leading to a decrease of the mechanical properties of mortar.
So, these composites can be advantageous for special applications where the main request is not for mechanical properties. 5.

Thus the major contributing factor for the abrupt increase in temperature was found.
The other important factors which are required to calculate angle of incident radiation are declination angle and hour angle both depends on location and time of the year.
The materials used for different parts of the cabin and their properties are listed in Table 1.
Table 1: Material properties of truck cabin parts S.
Numerical simulations have been carried out for various orientations of truck cabin with the same material properties and operating conditions.

Introduction Polysilazanes-derived ceramics for MEMS devices have excellent thermal and mechanical properties and good chemical resistance at high-temperature.
Moreover, the method of manufacturing such ceramics can be effectively employed to control the size and shape of MEMS devices, as well as material properties through tailoring the chemistry of the organic precursors.
These limitations are overcome by the addition of a thiol monomer to the system, thereby changing the predominant polymerization mechanism to step-growth thiol-ene polymerization mechanism, and exhibits several unique properties, including rapid curing in the presence of little or no photo initiator, delayed gelation, reduced sensitivity to oxygen inhibition, low volume shrinkage, high crosslink density and great mechanical property [2].
Besides the concentration of the photo initiator, the kinetics of the photo polymerization is also affected by the UV light intensity.
The activation energy and frequency factor are calculated as 13.97 kJ/mol and 54.0s-1.