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Identifying elastic properties of isotropic materials by finite element analyses and vibration data Marco Alfanoa, Leonardo Pagnottab and Giambattista Stiglianoc 1 Department of Mechanical Engineering, University of Calabria, 87036 Rende (CS) - Italy a alfano@unical.it, bpagnotta@unical.it, cstigliano@unical.it Keywords: elastic constants; isotropic materials; FEM; NDT.
In the present paper, an optimized search procedure is proposed which allows the material constants of isotropic plates to be non-destructively identified from vibration testing data and using finite element analyses.
The procedure has been applied using frequency data retrieved from the literature and a comparison with the results obtained by means of other test methodologies has shown that the proposed approach is effective.
The process starts assuming the guess value assigned by the user (Estart, νstart), then in the pre-processing stage the input file of the FEA code (MSC/NASTRAN [18]) is adjusted modifying the MAT1 bulk data entry which defines the isotropic stress-strain relationship.
Future work will be focused on the reduction of the solution time.

Data on the influence of various factors on balancing accuracy are presented.
(8) Applying equations (2) and (9), let us define the reduction effectiveness of the shaft deflection and the rotor unbalance: , (9) where: is the effectiveness of the reduction of the rotor shaft deflection (amplitude of the rotor vibrations) when the rotor speed is much higher than the critical speed; is the effectiveness of the reduction of the rotor unbalance at the same rotor speed, i.e. the efficiency of automatic balancing.

The reduction in mean forming load when ultrasonic vibration is applied to the die was attributed to several sources: the reduction of friction between die and specimen interface, stress superposition, absorption by dislocations of the ultrasonic vibration energy, acoustic softness.
This may lead to a fictious impression of friction reduction.
The numerical simulation agrees well with the experimental data during the first stage superimposed with ultrasonic vibration (T1).
It can be seen that the FEM data is bigger than experimental data when the engineering strain is equal to 0.4 while they are almost equal when the engineering strain is equal to 0.22.
It can be explained by the reduction in friction coefficient.

According to data released by the Ministry of Energy and Mineral Resources of the Republic of Indonesia, coal reserves in Indonesia are estimated to run out in 2036, oil reserves in 2028, and gas-phase fuel in 2027.
The weight reduction was almost 58% upon heating to 350 °C.
This mass reduction occurs due to the heat distribution by conduction in the furnace.
Based on the activation energy values in Table 1, it can be seen that the activation energy corresponding to the data value is at the R2.
Kinetic Analysis of Thermogravimetric Data Collected From Bigger Samples.

According to the analysis of real speech data collection simulation, improved spectral subtraction can effectively reduce the musical noise, can satisfy the requirement of speech enhancement.
The traditional spectral subtraction principle diagram B. improved spectral subtraction principle 1) A reduction of the weighted values ​​to be processed Traditional spectral subtraction adopts the method of minus the same noise power for the entire speech segment.
Therefore, there are some larger residual noises after the spectrum reduction sometimes.
Considering these two aspects, the improved spectral subtraction formula is as follows[1][4][5]: Experimental results show that a generally takes 3 ~ 5, b takes 0.01~0.5 can achieve better noise reduction and the effect of inhibiting pure tone noise is obvious. 2) Power spectrum correction processing We use and(k > 0) to calculate instead of andof the traditional spectral subtraction in the power spectrum.

From these damages, delamination is considered the most serious one as it can lead to a reduction of the mechanical properties of the laminate [10].
The reduction of delamination has been the subject of several studies, see for example, [12-16].
Thrust forces were monitored during drilling for thrust force data collection; delamination extension was carried out through digital scanner and enhanced digital radiography; mechanical testing was performed in order to evaluate mechanical strength loss due to hole machining.
During drilling, axial thrust forces were monitored with a Kistler 9257B dynamometer associated to an amplifier and a computer for data collection.
The tests were performed in a Shimadzu AG-X/100 kN Universal Testing machine equipped with the necessary accessories to run the different tests and connected to a computer for machine control and data acquisition and processing.

The predictions of the earing profile after each step are compared to experimental data.
Thereby it is assured that the reduced data is representative for the considered aluminum alloy.
In Fig. 2 a comparison of the pole figures of the original (left) and the reduced data (right) is shown.
Although the latter consists of only 2% of the original orientation data, the pole figures are still in good agreement.
Böhlke, Preprocessing of Texture Data for an Efficient Use in Homogenization Schemes.

Data from Literature Table 2 shows the study of selected diesel-powered cars that give 30% saving in fuel economy.
Survey This study uses primary data from questionnaires.
The research methodology includes sampling design, questionnaire creation, data collection and data analysis.
After collecting data, data analysis was conducted using Microsoft Office Excel and IBM SPSS Statistics 2.0.
All data were analyzed according to the objectives of the study and presented in tables and diagrams.

Structure of fixed data collection node Data Acquisition Module.
Data Processing Module.
When the nRF24E1 working in ShockBurst™, it transmits data at a very high rate thus enabling extremely power reduction, system cost lower and risk reduction of ‘on-air’ collisions due to short transmission time， which can ensure the effectiveness and reliability in communication [3].
Preamble is data header.
PAYLOAD is data section, the total number of bits in a ShockBurst™ RF package may not exceed 256 bits, maximum length of payload section: DATAx _W(bits) = 256 - ADDR _W - CRC Shorter address and CRC can leave more room for payload data in each package which can improve the transmission efficiency, but it will make reliability reduction.

Temperature programmed reduction (H2-TPR) was carried out in a thermogravimetric analyzer (Shimazu, TGA-50).
The diffraction data of calcium ferrite solution (mostly Ca2Fe2O5) prepared from the mixture of CaO and Fe2O3 at Ca/Fe=1.00 were shown in Fig. 2 (left).
H2-temperture programmed reduction.
This may probably due to the reduction of residual Fe2O3 in the calcium ferrite solution.
According to Raman spectroscopic datum of the sample at Ca/Fe=1.00; (b), an intense absorption at 1093cm -1 is observed.