scholarly journals Determination of a non-measurable quantity using information from calculations and experimental measurements: application to the damage rate determination

2017 ◽  
Vol 153 ◽  
pp. 01025
Author(s):  
Stéphane Bourganel ◽  
Jean-Claude Nimal
Keyword(s):  
Experimental Measurements ◽  
Measurable Quantity ◽  
Damage Rate

scholarly journals REMOTE DETECTION OF OBJECTS IN THE PRESENCE OF INTERFERENCE IN IR-THZ WAVELENGTH RANGE

2021 ◽  
Vol 8 ◽  
pp. 254-261
Author(s):  
Valerik S. Ayrapetyan
Keyword(s):  
Object Detection ◽  
Wavelength Range ◽  
High Accuracy ◽  
Remote Detection ◽  
Movement Direction ◽  
Experimental Measurements ◽  
Detection Of Objects

The paper deals with issues of object detection in conditions of smoke, dust curtains and fog in the IR-THz ranges of electromagnetic wavelengths. It is shown that remote detection of objects and determination of their movement direction under conditions of real interference in the atmosphere is provided with high accuracy and reliability in the IR-THz ranges. The results of experimental measurements and the performed calculations show that to reduce the attenuation of the signal received from the object under conditions of smoke, dust curtains and fog, it is necessary to use IR and THz methods together.

scholarly journals Prediction and measurement of selected phase transformation temperatures of steels

2017 ◽  
Vol 53 (3) ◽  
pp. 391-398 ◽  
Author(s):  
O. Martiník ◽  
B. Smetana ◽  
J. Dobrovská ◽  
A. Kalup ◽  
S. Zlá ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Phase Transformation ◽  
Statistical Evaluation ◽  
Precise Determination ◽  
Experimental Measurements ◽  
Transformation Temperatures ◽  
Literature Research ◽  
Computational Thermodynamic ◽  
Peritectic Transition

The study deals with precise determination of phase transformation temperatures of steel. A series of experimental measurements were carried out by Differential Thermal Analysis (DTA) and Direct Thermal Analysis (TA) to obtain temperatures very close to the equilibrium temperatures. There are presented results from the high temperatures region, above 1000?C, with focus on the solidus temperatures (TS), peritectic transition (TP) and liquidus (TL) of multicomponent steels. The data obtained were verified by statistical evaluation and compared with computational thermodynamic and empirical calculations. The calculations were performed using 15 empirical equations obtained by literature research (10 for TL and 5 for TS), as well as by software InterDendritic Solidification (IDS) and Thermo-Calc (2015b, TCFE8; TC). It was verified that both thermo-analytical methods used are set correctly; the results are reproducible, comparable and close to equilibrium state.

Determination of the Anand Viscoplasticity Model Constants for SnAgCu

2005 ◽  
Author(s):  
Bryan Rodgers ◽  
Ben Flood ◽  
Jeff Punch ◽  
Finbarr Waldron
Keyword(s):  
Fatigue Life ◽  
Plastic Strain ◽  
Test Specimen ◽  
Strain Curve ◽  
Temperature Cycling ◽  
Displacement Rate ◽  
Experimental Measurements ◽  
Strain Rates ◽  
Constant Displacement

The major focus of this work was the determination of the nine constants required for Anand’s viscoplastic constitutive model for a lead-free solder alloy, 95.5Sn3.8Ag0.7Cu and to compare them with those for SnPb. The test specimen was a cast dog bone shape based on ASTM E 8M-01, with a diameter of 4mm and a gauge length of 20mm. A series of tensile experiments were carried out: constant displacement tests ranging from 6.5 × 10−5/s to 1.0 × 10−3/s at temperatures of 20°C, 75°C, and 125°C; constant load tests at a range of loads from 10MPa to 65MPa, also at temperatures of 20°C, 75°C, and 125°C. A series of non-linear fitting processes was used to determine the model constants. Comparisons were then made with experimental measurements of the stress-plastic strain curves from constant displacement rate tests: it was found that the model matched the experimental data at low strain rates but did not capture the strain hardening effect, especially at high strain rates. A finite element model of the test was also constructed using ANSYS software. This software includes the Anand model as an option for its range of viscoplastic elements, requiring that the nine constants be input. In this case, an 8-noded axisymmetric element (VISCO108) was used to model the test specimen under constant displacement rate loading. The model was then used to predict the stress-plastic strain curve and this was compared to both the experimental measurements and the fitted Anand model. Reasonable agreement was found between the Anand model and the FE predictions at small strain rates. Finally, a BGA device was simulated under accelerated temperature cycling conditions using ANSYS with the fitted Anand for the SnAgCu solder joints. A Morrow-type fatigue life model was applied using empirical constants from two published sources and good agreement was found between experiment and predicted fatigue life.

scholarly journals B → D*lv at non-zero recoil

2018 ◽  
Vol 175 ◽  
pp. 13003 ◽  
Author(s):  
Alejandro Vaquero Avilés-Casco ◽  
Carleton DeTar ◽  
Daping Du ◽  
Aida El-Khadra ◽  
Andreas Kronfeld ◽  
...  
Keyword(s):  
Matrix Element ◽  
Decay Rate ◽  
Form Factors ◽  
Heavy Quarks ◽  
Experimental Measurements ◽  
Ckm Matrix ◽  
Preliminary Results ◽  
Future Plans

We present preliminary results from our analysis of the form factors for the B → D*lv decay at non-zero recoil. Our analysis includes 15 MILC asqtad ensembles with Nf = 2 + 1 flavors of sea quarks and lattice spacings ranging from a ≈ 0.15 fm down to 0.045 fm. The valence light quarks employ the asqtad action, whereas the heavy quarks are treated using the Fermilab action. We conclude with a discussion of future plans and phenomenological implications. When combined with experimental measurements of the decay rate, our calculation will enable a determination of the CKM matrix element |Vcb|.

On the Determination of the Cholesteric Screw Sense by the Grandjean-Cano-Method

1980 ◽  
Vol 35 (6) ◽  
pp. 619-622 ◽  
Author(s):  
Paul R. Gerber
Keyword(s):  
Theoretical Treatment ◽  
Experimental Measurements ◽  
Polarizing Microscope

A theoretical treatment is presented for the determination of the screw sense of a cholesteric substance in a Grandjean-Cano-wedge by observing the sample in a polarizing microscope. For comparison some experimental measurements are given

Free Vibration of Continuous Skin-Stringer Panels

1960 ◽  
Vol 27 (4) ◽  
pp. 669-676 ◽  
Author(s):  
Y. K. Lin
Keyword(s):  
Free Vibration ◽  
Boundary Conditions ◽  
Natural Frequencies ◽  
Normal Modes ◽  
Time Dependent ◽  
Experimental Measurements ◽  
Structural Configuration ◽  
Modes Of Vibration ◽  
Fuselage Skin

The determination of the natural frequencies and normal modes of vibration for continuous panels, representing more or less typical fuselage skin-panel construction for modern airplanes, is discussed in this paper. The time-dependent boundary conditions at the supporting stringers are considered. A numerical example is presented, and analytical results for a particular structural configuration agree favorably with available experimental measurements.

scholarly journals Experimental Measurement of Conducted Emissions Generated by Static Converters in Common and Differential Modes

2021 ◽  
Vol 23 (3) ◽  
pp. 273-279
Author(s):  
Helima Slimani ◽  
Abdelhakim Zeghoudi ◽  
Abdelber Bendaoud ◽  
Abdeldjalil Reguig ◽  
Baghdadi Benazza ◽  
...  
Keyword(s):  
Energy Conversion ◽  
Experimental Measurement ◽  
Experimental Measurements ◽  
Power Electronic ◽  
Power Electronic Converters ◽  
Static Converters ◽  
Energy Conversion Systems ◽  
Conducted Emissions

The commutation of semiconductors and their interactions with parasitic elements linked to the environment is known to be the main source of interferences conducted in power electronic converters. Thus, identifying these sources of interferences in commutation cells and determining the level of these conducted emissions generated in energy conversion systems presents a major challenge for designers. In this work, a study of the electromagnetic interferences (EMI) generated by the association of serial rectifier-chopper connected to a Line Impedance Stabilization Network (LISN) is proposed, in which a determination of these interferences is presented in both common and differential modes. All simulations are carried out using the LT-spice software and the results obtained are validated by experimental measurements realized at APELEC laboratory (University of Sidi Bel-Abbes, Algeria).

scholarly journals Determination of Moving Speed of School Age Children

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Milan Simeunović ◽  
Ilija Tanackov ◽  
Pavle Pitka ◽  
Milja Simeunović ◽  
Zoran Papić
Keyword(s):  
School Age Children ◽  
Experimental Measurements ◽  
School Age ◽  
Age And Gender ◽  
Average Speed ◽  
Gender And Age ◽  
And Gender ◽  
Moving Speed ◽  
Number Of Authors

School age children (pedestrians) can move at different speeds, which are conditioned by certain parameters. Not all parameters have the same effect on the pedestrian speed. According to the literature, gender and age are the most researched parameters that have an impact on the speed of pedestrians. However, a small number of authors have dealt with the influence of movement regimes (slow, normal, fast, run, and rush) on pedestrian speed, while at the same time taking into account age and gender. For that reason, this article measured the speed of movement of school age children by movement regimes, taking into account age and gender. Within the same movement regime, the influence of age, sex, height, and weight on the speed of movement was investigated. Experimental measurements of the speed of movement of pedestrians aged 7 to 20 years were performed. Based on the results of measurements and statistical analyzes, recommendations on the average speed of movement regimes, age, and gender are given.

scholarly journals An Evaluation of Material Properties Using EMA and FEM

2016 ◽  
Vol 24 (39) ◽  
pp. 15-22
Author(s):  
Rastislav Ďuriš ◽  
Eva Labašová
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Structural Dynamics ◽  
Material Properties ◽  
Elasticity Modulus ◽  
Natural Frequencies ◽  
Optimization Methods ◽  
Experimental Measurements ◽  
Element Analysis

Abstract The main goal of the paper is the determination of material properties from experimentally measured natural frequencies. A combination of two approaches to structural dynamics testing was applied: the experimental measurements of natural frequencies were performed by Experimental Modal Analysis (EMA) and the numerical simulations, were carried out by Finite Element Analysis (FEA). The optimization methods were used to determine the values of density and elasticity modulus of a specimen based on the experimental results.

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