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These include the: · Inertias (motor, gears, clutch, bearing, spindle) · Stiffnesses and dampings (clutch, gears, bearing, spindle (axial, torsional), nut) Figure 4: Simulation model of the mechanics with model reduction for indirect drives Caused by the comprehensive data, the synthesis of these parameters as well as the used friction model (Coloumb friction) can be found in detail in [6].
Due to the mechanical complexity of electromechanical linear axes, a reduction of the system order is expedient.
Practical investigations as well as the prevailing view in literature [7, 8] justify the reduction to a two-mass system.
The values of the motor torque (184 Nm), motor shaft diameter (48 mm) and motor inertia (140 10-4 kgm²) are quite similar to the data of the associated motor of the machine axis.

Introduction Based on the State Fire Service data, it was estimated that only in 2017 there were 125,892 fires in Poland (Central Europe) with the total cost of property damage amounting to USD 313,012,525 [1].
The aim of the study was to identify the crystalline phases present in the histidine diphosphate in comparison to the reference samples of substrates used in the synthetic process as well as literature data.
Cone calorimeter results of unmodified epoxy resin (EP) and resin modified with commercial flame retardant (APP) as well as developed flame-retardant system (EP/S+HF) (standard deviation) Sample designation TTI [s] pHRR [kW/m2] THR [MJ/m2] MARHE [kW/m2] SEA [m2/kg] TSR [m2/ m2] EP 51(17) 1156 (221) 184 (7) 569 (82) 1582 (554) 10353 (3672) EP/APP 52 (5) 227 (5) 94 (10) 148 (10) 508 (9) 2174 (211) EP/S+HF 35 (2) 211 (8) 75 (32) 109 (14) 477 (83) 1463 (537) The use of the developed flame retardant system led to a reduction in time to ignition (TTI) to as little as 35s from the 51s for EP and 52s for EP/APP.
More significantly, the highest reduction in maximum values of heat release rate (pHRR), which is the most important variable used to assess the intensity of fire, was noted for EP/S+HF.
Introduction of 20 wt% of flame retardant system led to a reduction in the time after which the samples ignited but also to a sharp drop in the pHRR, THR, MARHE and TSR values.

The accuracy of numerical simulation strictly depends on the input data, which are the physical properties of material.
To simulate the forging of AZ80 magnesium alloy wheel using an implicit FE code MSC/Superform, the data on the flow stress as function of strain, strain rate and temperature established based on the earlier work have to be introduced into the FE package.
Fig.2 shows the schematic diagram of metal flow with different tool radius at the same reduction in height.
When tool radius is 30mm, irrespective of the reduction in height, the folding defect was not noticed compared to the smaller tool radius.
Table 1: Chemical composition of AZ80 billet selected for the study [mass%] The magnesium alloy can was extruded at 400@ with a reduction ratio of 5:1.

The finite element method is an effective way for quantifying mechanical properties of multilayered materials and providing detailed data for better description of their mechanical behaviour under depth-sensing indentation.
Mechanical properties of these materials were selected based on previously reported experimental data [7].
Increasing the number of titanium interlayers in the coating leads to a reduction in the coating's hardness of up to 3.5 % (Fig. 2b).
The reduction of Young's modulus of the coatings with titanium interlayers is 2.5% if one interlayer is present in the coating.
The reduction in Young's modulus is more significant for coatings with titanium interlayers.

Probably the best-known empirical model is that of Delany and Bazley [12], who presented simple power-law relations obtained by fitting a large amount of experimental data.
Noise reduction coefficient (NRC), which is a simple quantification of absorption of sound by material, is normally calculated for the range of frequencies below 2500 Hz.
Table 1 shows the data for the noise reduction coefficient for the three flow resistivity values.
NRC for the date palm fiber sample of different flow resistivity values Flow Resistivity (kPa.s/m2) Noise Reduction Coefficient 250 Hz 500 Hz 1000 Hz 2000 Hz NRC 4.26 00.07 00.16 00.31 00.55 0.27 2 00.07 00.13 0.23 00.40 0.21 10 00.05 00.17 00.41 00.75 0.35 Conclusions In this study, sound absorption of date palm fiber was investigated.

The experimental data have been statistically analysed using the Weibull distribution law [6].
An average thickness reduction of 0.5 µm can be estimated each 1000 h of aging for the different thicknesses indicating that this variation is not bulk dependent.
The first degradation at short aging period can be related to the effect of the craters formation on the dielectric breakdown in addition to the thickness reduction.
After 5000 h of aging the two films of 1.5 and 3 µm are short circuited, while a reduction of the breakdown voltage of 87, 75 and 60% is observed for the 4.2, 5.7 and 8 µm respectively.
Data in boxes are refered to extrapolated.

The simulation-based test intended to examine effects of different structures without and with an elastomeric protective panel clearly showed the key role of such panel in reduction of destructive effect of the detonation wave.
Additionally, the data presented in Tab. 4 confirmed the good correlation between computation results and experimental measurements.
Comparison data for cylinder deflection recorded from performed tests.
The thickness reduction of the elastomeric panel.
The performed tests confirmed that due to the plastic deformations in the elastomeric panel the major part of the violating wave was simply consumed by its and, thanks to that, allowed for reduction of the tube wall deflection.

From the cluster approach, the spin-orbit coupling coefficients ζ and ζ' and the orbital reduction factors k and k’ containing the ligand orbital and spin-orbit coupling contributions are expressed as follows [10] : ζ= Nt (ζd0 + λt2ζ p0 /2), ζ' = (Nt Ne)1/2 (ζd0 - λt λeζ p0 /2), k= Nt (1+ λt2/2), k'= (Nt Ne)1/2 [1-λt (λe + λs A)/2]
By using the free-ion values ζd0 ≈ 356 cm-1 [17] for Fe+ and ζp0 ≈ 220 cm-1[18] for F-, the spin-orbit coupling coefficients ζ, ζ’ and the orbital reduction factors k and k’ are acquired from Eq.(5).
Substituting the above values into Eq (1), the g factors are calculated and compared with the experimental data in Table 2.
The effective impurity-ligand distances R (in Ǻ), group overlap integrals Sγ (and also the integral A), cubic field parameter Dq (in cm-1 ) and covalency factor N, the normalization factors Nγ and the orbital admixture coefficients λγ, the spin-orbit coupling coefficients ζ and ζ´ (in cm-1 )and the orbital reduction factors k and k´ for the cubic Fe+ centers in LiF and NaF.
Discussion Table1 reveals that the theoretical g factors for both Fe+ centers in LiF and NaF show good agreement with the experimental data.

Statistical data showed that the plant area of FUM in China is 16000 hm2 and the production is 20000 tons in 2006, the area is 18000 hm2 and the production is 24000 tons in 2010, up 12.5% and 20% respectively[3].
Table 1 Dimensions of various shapes of FUM Shape Height (c) Width (b) Length (a) Three-axis mean diameter (a+b+c)/3 Height/Length (c/a) Height/Width (c/b) Width/Length (b/a) Peach shaped FUM 1 7.72 9.27 10.95 9.31 0.71 0.83 0.85 2 0.77 0.81 0.70 0.59 0.07 0.06 0.07 Small flat FUM 1 11.68 17.52 19.47 16.23 0.60 0.67 0.90 2 1.91 1.58 1.14 1.32 0.06 0.07 0.05 Note: 1-mean values of parameters, 2-standard deviation of parameters Based on the data in Table 1, axial mean dimensions relation of peach shaped and small flat FUM is a>b>c.
Screen surface is composed of upper screen surface, middle screen surface, and under screen surface; drive system is composed of reduction wheel, crank, connecting rod, oscillating bar, and rolling wheel; rack is composed of run wheel which , beam, rack leg, adjustment screw of screen angle; removing inclusion equipment is composed of enclosure, blade, and revolving shaft.
FUM are divided into four grades, the matter which is lighter than FUM in mixture is separated using fan spindle droved by reduction wheel with diesel.
Fig.1 Kinematic scheme of mechanism of grade sieve machine Fig.2 Kinematic scheme and loading conditions of grade sieve 1.Walking wheel 2.Regulating handle 3.Reduction wheel 4.Crank 5.Diesel 6.Connecting rod 7.

Data Envelopment Analysis Data Envelopment Analysis identifies the efficient units from a set and combine them to generate an efficient frontier that is used as a benchmark to measure the relative efficiency of inefficient units.
Sinuany-Stern: Review of ranking methods in the data envelopment analysis context.
Hogan, Data envelopment analysis: critique and extensions, in: Measuring Efficiency: an Assessment of data Envelopment Analysis, edited by R.H.
Cook: Preference voting and project ranking using data envelopment analysis and cross-evaluation.
Green: Comparing products using data envelopment analysis.