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Calculated on the influence of strata movement, there is a empirical formula for the coal’s alternate distance.It is necessary to analyze the factors in the formula Introduction Close distance coal seam mining in working face of the reasonable distance determination is often encountered in coal mining, which directly affects the upper and lower two layers of the work of the safe production and production organization, reasonable determination of upper and lower working face fault distance can avoid two coal face each other at the same time because of adverse effects caused by mining.
can be used to calculate the coal’s alternate distance Organization of the Text The empirical formula to calculate the coal’s alternate distance Calculated on the influence of strata movement, there is a formula for the coal’s alternate distance in experience: Fig.1 The model of the minimum offset under the influence of strata movement H—the space of coal seam; L—Considering the stability of the roof strata in the upper face and the safety distance of the upper and lower face caused by the unbalanced recommended speed, generally not below) 20 ~ 25 m; δ—Angle of rock movement,the hard rock is 60 ° ~ 70 °, the weak rock is 45 ° ~ 55 ° b—The biggest accused of zenith distance of the working face in the upper coal seam Using this method to mine the close distance coal seam, it is important to note tha t the offset of the up and down coal mining face must not be too small, so as to avoid the powered impact on the floor of coal because of the seam roof caving and the affect
The rock layer’s trend subsidence angle δ is not only depended by rock properties but also by the mining methods, mining thickness, mining depth, goaf area, and others factors.
And get the empirical formula: (1) In the formula: a, b are the physical and mechanical property of rock.
So based on the mining depth, mining thickness, and rock’s physical and mechanical properties, we can adjust the size of mining face displacement according to adjust the rock movement angle. ③The impact of safe distance L on the coal’s alternate distance Actually, In formula (1) the main factors influencing the concurrent slicing distance is the value of L, L is distance of the upper face roof stability and upper and lower face advancing speed unbalanced considering the safe, the value of L mainly depends on periodic weighting step distance, When the working face advancing to a certain distance, basic roof cantilever under the action of gravity and the overburden, and will produce fracture caving, at this time also will bring face pressure phenomenon.

Three samples of both concrete were tested for basic physical, mechanical and hydric properties.
Experimental measurements and results Basic physical and mechanical properties.
Basic physical and mechanical properties of both types of concrete are summarized in Table 2.
Water transport properties.
All these factors help to prolong the service life of the structure and the mean time between repairs.

The response surface model was used to study different factors, such as sludge concentration, space between membranes and aeration rate, affecting membrane fouling of the upper and lower layer membrane module.
Results and discussion Use Design Expert 7.5 software for Box-Behnken Design (3 factors 3 levels).
This was mainly attributed to the change of sludge properties, such as increase of viscosity, colloids concentration and dissolved organic matters, when sludge concentration increased.
Table 5 represents the settlement optimization condition which designed the target conditions and weight of different factors.
Floc destruction and its impact on dewatering properties in the process of using flat-sheet membrane for simultaneous thickening and digestion of waste activated sludge.

The measurement of the ferroelectric hysteresis curves confirmed that the structural changes induced by different processing parameters affected the ferroelectric properties of the material.
In order to use these ceramics to their full potential, thorough research of their properties is needed [1].
In order to optimize the film properties and performance it is essential to understand the factors that influence these properties and, in recent, an extensive experimental work was carried out on the characterization of these ferroelectric thin films [3].
The main objective of this work is to study the properties of Si/SiO2/Ti/Pt/PZT/Al stacks in order to optimize its piezoelectric properties so it can be used as micro-actuator for integrated optic devices.
The processing conditions were changed in order to maximize the ferroelectric and piezoelectric properties.

Electroless nickel plating has been used in many industrial applications due to its outstanding deposition properties, such as excellent corrosion, wear resistance and deposit uniformity [3].
The purpose of this work was to develop electroless plating different combinations of Ni–Cu–P onto polyester fabric and investigate the properties of plated fabric, such as the surface morphology, crystal structure, composition, surface resistance and EMI shielding effectiveness were also studied.
Results and discussion Surface morphology The surface morphology of metallic fabric may affect their electrical, mechanical, and optical properties.
Tinted fabric Figure 1 Scanning electron microscopy image of plated Fabric Electromagnetic shielding The electromagnetic shielding of electroless plated fabric was affect by a variety of factors, especially for the thickness, uniformity of the metal layer and sort of metal.
For the same metal, the thickness of the metal layer is the most important factor and for the same weight increasing rate, the sort of metal is the most important factor.

Reliability analysis method of slope stability The fundamental principle of Monte-Carlo Slope stability factor F is the function controlled and affected by numerous variables.
Corresponding stability factor Fj can be calculated from formula (1).
As all parameters affecting stability of slope are random variables, however, not all random variables have the same degree of influence, the variables having little influence can be taken as the definite values to simplify the calculation.
Physical and mechanical property index and shear strength statistics of slip soil of landslide is respectively shown in table 1and table 2.
Stability factor F is equal to 0.890.

But there are many formulations of concrete, which provide varied properties.
Physical and mechanical properties of the artificial sands are shown in Table 2.
Four factors are water-cement ratio, flyash content, admixture content and sand ratio.
Table 5 shows the details of four factors and three levels orthogonal table.
[In Chinese] [9] The ministry of construction of china: Standard for the test method of mechanical properties on ordinary concrete, GB/T50081-2002, (China Plan Press, China 2002).

The specimens were made of the AlCu4Mg1 (EN AW-2017A) aluminium alloy with mechanical properties shown in Table 1 and described in the standard PN-EN 573 of 1997.
Alloys of aluminium with copper and magnesium, that is duralumin, belong to alloys characterised by supreme strength properties.
Mechanical properties of the AlCuMg1 aluminium alloy.
Differences in the values of coefficients C and m prove that ratio R affects shift C and inclination m of the curve.
American Society of Mechanical Engineers. 85 (1963) 528-534.

The surface quality is a critical factor affecting the performance and reliability of advanced ceramics.
Introduction A critical factor affecting the performance and reliability of advanced ceramics is the quality of the resulting surface by lapping and polishing.
Regarding 4 factors - 3 levels situations, there are 3 4 possible combinations and would require 81 trial runs for a factorial experiment.
In this study, standard 4 factors, 3 levels L9 (3 4) OA is used in this study.
D column is empty, and stands for unknown factor.

Diamond-Si nanostructured composites were obtained by cyclic high pressure and high temperature sintering with different processing conditions to examine the dominant microstructural factors and the abrasive wear resistance.
Recent studies [9] have shown that nanostructured diamond-SiC composites exhibit an even superior improvement in mechanical properties, especially the toughness.
This probably affects the mechanical properties of composites.
Effect of Nanodiamond Addition on the Mechanical Properties of Polycrystalline Metallic and Polymeric Composites.
Effect of the carbon black nanopowder on the mechanical properties of B-Si-Cu-Diamond composite.