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Online since: March 2011
Authors: Stefania Bruschi, Alberto Molinari, Ivan Lonardelli, Paolo Bosetti
Xray diffraction (XRD) analysis was utilized to determine the fraction of transformed martensite along the wall of formed parts at different levels of thickness reduction.
For each sample, the value of approximate thickness reduction was determined from the measured part thickness profile.
The obtained data are first refined taking into account the instrument parameters and background, then the crystallographic and microstructural parameters and finally all the parameters including the volume fractions of the phases.
Fig. 2b) shows the martensite volume fraction during the SPIF process as a function of the part thickness reduction.
The spectra are obtained from the two sides of the same sample (sample n.4 with thickness reduction of 24%) accounting the “contact tool face” (a) and the “external face” (b).
For each sample, the value of approximate thickness reduction was determined from the measured part thickness profile.
The obtained data are first refined taking into account the instrument parameters and background, then the crystallographic and microstructural parameters and finally all the parameters including the volume fractions of the phases.
Fig. 2b) shows the martensite volume fraction during the SPIF process as a function of the part thickness reduction.
The spectra are obtained from the two sides of the same sample (sample n.4 with thickness reduction of 24%) accounting the “contact tool face” (a) and the “external face” (b).
Online since: November 2012
Authors: Peng Li, Yan Xiong, Ke Zhao
And at the same time, in the routing decisions this paper chooses fragmentary active routing decisions, further energy consumption and transmission delay reduction.
Store the paths in the routing table according to the priority classification, and then when the further data comes; direct transmit the data according to different choices of the routing table of the data in the right path.
When sending data, the energy consumption model is as follow:
In route choice, due to the different data, the routing requirements are not the same, some data require for real-time, some data require for reliability.
When first transmit data, the source node find all feasible paths to meet the conditions for data transmission based on MMSPEED agreement.
Store the paths in the routing table according to the priority classification, and then when the further data comes; direct transmit the data according to different choices of the routing table of the data in the right path.
When sending data, the energy consumption model is as follow:
In route choice, due to the different data, the routing requirements are not the same, some data require for real-time, some data require for reliability.
When first transmit data, the source node find all feasible paths to meet the conditions for data transmission based on MMSPEED agreement.
Online since: August 2018
Authors: O. Bohórquez, Octavio Andrés González-Estrada, Alberto Pertuz, Sergio Andrés Ardila Parra
An estimation of the shaft’s field of stresses and deformations was made, taking as reference the energy consumption data provided by the process[7].
Operational torque was calculated using voltage 220 (V) and current 244(amp), data collected in the workplace and applying reduction due to mechanical mounting and motor efficiency.
(1) This power was taken as a reference to calculate the torque value, using power mechanics equation[8], with rotational speed directly on the shaft of 16 (rpm), and considering reduction ratio by gearbox, effective torque was calculated as 34893 (N.m).
Table 2 shows a reduction in hardness in specific areas of interest.
Data taken area Rockwell C Average Shaft with original condition Lengthwise section 36, 37, 36 36.33 Transversal section 36, 37, 37 36.66 Shaft with welding process applied Lengthwise section 28, 28, 27, 30, 30, 30, 30, 31, 32, 31.5, 34, 35, 34, 33 28.54 Transversal section 28, 30, 31, 30, 31, 32, 32, 32, 33, 34 31.33 Conclusions Failure mode in the shaft was characterized by a repairment for the welding process, due to premature plastic deformation on the hexagonal peripheral zone, this repairment persecuted to recover the support area to helical sections, after the intervention, was evidenced a nucleation of crack, and propagation of fissure, that led to breaking off the shaft.
Operational torque was calculated using voltage 220 (V) and current 244(amp), data collected in the workplace and applying reduction due to mechanical mounting and motor efficiency.
(1) This power was taken as a reference to calculate the torque value, using power mechanics equation[8], with rotational speed directly on the shaft of 16 (rpm), and considering reduction ratio by gearbox, effective torque was calculated as 34893 (N.m).
Table 2 shows a reduction in hardness in specific areas of interest.
Data taken area Rockwell C Average Shaft with original condition Lengthwise section 36, 37, 36 36.33 Transversal section 36, 37, 37 36.66 Shaft with welding process applied Lengthwise section 28, 28, 27, 30, 30, 30, 30, 31, 32, 31.5, 34, 35, 34, 33 28.54 Transversal section 28, 30, 31, 30, 31, 32, 32, 32, 33, 34 31.33 Conclusions Failure mode in the shaft was characterized by a repairment for the welding process, due to premature plastic deformation on the hexagonal peripheral zone, this repairment persecuted to recover the support area to helical sections, after the intervention, was evidenced a nucleation of crack, and propagation of fissure, that led to breaking off the shaft.
Online since: July 2012
Authors: Woo Tai Jung, Jong Sup Park, Seung Han Kim
The measurement of the experimental data was conducted using a static data logger and a computer at a sampling rate of 1 Hz.
Fig. 9 compares the data measured at the top of the lateral concrete (①) and at the bottom of FRP (②) of Fig. 7 with the analytic values.
Fig. 10 compares the data measured at the bottom of the FRP upper flange (③) and at the top of the FRP bottom flange (④) with the analytic values.
However, the data measured at the upper flange show some difference with the analytic values.
Since the measured and computed values of the strain at the FRP upper flange (④) and the bottom of the lateral FRP (②) are similar and can be interpreted as a result indicating perfect bond behavior of FRP and concrete, this difference can be assumed as an error in the data measured in the FRP upper flange.
Fig. 9 compares the data measured at the top of the lateral concrete (①) and at the bottom of FRP (②) of Fig. 7 with the analytic values.
Fig. 10 compares the data measured at the bottom of the FRP upper flange (③) and at the top of the FRP bottom flange (④) with the analytic values.
However, the data measured at the upper flange show some difference with the analytic values.
Since the measured and computed values of the strain at the FRP upper flange (④) and the bottom of the lateral FRP (②) are similar and can be interpreted as a result indicating perfect bond behavior of FRP and concrete, this difference can be assumed as an error in the data measured in the FRP upper flange.
Online since: May 2025
Authors: Opeyemi Owolabi, Oluwamayowa Musa, Funso Kehinde Ariyo
The available data are the locked-rotor torque (starting torque), breakdown torque, and full-load
torque.
The errors F1, F2, and F3 are computed using the available data from the sample motors, that is, 5 hp, 50 hp, and 500 hp.
The manufacturer-supplied data from the respective datasheets of the three motors are presented in Table 1.
Using the performance characteristics, majorly considering the torque and other nameplate data to minimize the deviation between the estimated and manufacturer data.
Rabelo, A High Precision Method for Induction Machine Parameters Estimation From Manufacturer Data, IEEE Trans.
The errors F1, F2, and F3 are computed using the available data from the sample motors, that is, 5 hp, 50 hp, and 500 hp.
The manufacturer-supplied data from the respective datasheets of the three motors are presented in Table 1.
Using the performance characteristics, majorly considering the torque and other nameplate data to minimize the deviation between the estimated and manufacturer data.
Rabelo, A High Precision Method for Induction Machine Parameters Estimation From Manufacturer Data, IEEE Trans.
Online since: May 2011
Authors: Nian Ping Liu, Hong Tu Wang, Zhi Gang Yuan
Rough Set
The concept of rough set was originally proposed by Pawlak as a mathematical approach to handle imprecision, vagueness and uncertainty in data analysis[7].
, when output data is continuous data, it must be changed into discrete data.
In this paper, a decision table was formed by discrete data which continuous attributes were changed into discrete data based on information entropy.
Rough set theory process entirely from the actual data, mine knowledge form hidden data, reveal the internal laws of the objective, without any influence of subjective factors, so the conclusion is more substantial and more meaningful. 2.
Rough set needs change continuous data into discrete data, so the discrete way determines the cuts of continuous data, which have an important influence on analysis, but the discrete way is lack of specific standards at present and it needs further research.
, when output data is continuous data, it must be changed into discrete data.
In this paper, a decision table was formed by discrete data which continuous attributes were changed into discrete data based on information entropy.
Rough set theory process entirely from the actual data, mine knowledge form hidden data, reveal the internal laws of the objective, without any influence of subjective factors, so the conclusion is more substantial and more meaningful. 2.
Rough set needs change continuous data into discrete data, so the discrete way determines the cuts of continuous data, which have an important influence on analysis, but the discrete way is lack of specific standards at present and it needs further research.
Online since: April 2008
Authors: K. Zarrabi, A. Basu
Also, the reduction of plastic collapse pressure with ovality is small for
a thick tube bend when compared with that for a thin tube bend.
When data are assumed to fit a mathematical distribution, we are adding information that helps us to model the available data.
ANN models the data that are presented to it during the training stage without assuming a particular distribution.
After the network is trained it is used to simulate or predict plastic collapse pressures using the tube dimensions and ovality data as input.
[6] Zarrabi K, Estimating the plane-strain fracture toughness under mode I from the uniaxial tensile data, Proceedings of the Structural Integrity & Failure conference, CD-ROM, Sydney, Australia, 27 - 29 September (2006), ISBN: 1 876855 26 6.
When data are assumed to fit a mathematical distribution, we are adding information that helps us to model the available data.
ANN models the data that are presented to it during the training stage without assuming a particular distribution.
After the network is trained it is used to simulate or predict plastic collapse pressures using the tube dimensions and ovality data as input.
[6] Zarrabi K, Estimating the plane-strain fracture toughness under mode I from the uniaxial tensile data, Proceedings of the Structural Integrity & Failure conference, CD-ROM, Sydney, Australia, 27 - 29 September (2006), ISBN: 1 876855 26 6.
Online since: January 2020
Authors: Kai Bo Cui, Hai Tao Sun, Yun Peng Huang, You Cai Jiang
The target plate was divided using a C3D8R unit (8-node hexahedral linear reduction integration unit), the number of units was 49,972, and the number of nodes was 55,566.
The test data is shown in Table 1.
Tab.1 Effect of impact velocity on erosion wear impact speed(m/s) wear weight loss (mg) erosion rate (mg/g) enhancement coefficient KW 200 0.216 20.67 1.000 300 0.595 56.95 2.755 400 0.925 88.12 4.263 500 1.723 164.85 7.975 600 2.741 262.26 12.688 It can be seen from the simulation test data of Table 1 that, the erosion rate of the particles has a significant effect on the erosion wear of the throttling ring.
The correlation coefficient R between the fitted curve and the original data is 0.99233.
According to the test data and the curve rule analysis, for the aluminum brass alloy, when the erosion particles impact at 15°~45°, the target damage is severe.
The test data is shown in Table 1.
Tab.1 Effect of impact velocity on erosion wear impact speed(m/s) wear weight loss (mg) erosion rate (mg/g) enhancement coefficient KW 200 0.216 20.67 1.000 300 0.595 56.95 2.755 400 0.925 88.12 4.263 500 1.723 164.85 7.975 600 2.741 262.26 12.688 It can be seen from the simulation test data of Table 1 that, the erosion rate of the particles has a significant effect on the erosion wear of the throttling ring.
The correlation coefficient R between the fitted curve and the original data is 0.99233.
According to the test data and the curve rule analysis, for the aluminum brass alloy, when the erosion particles impact at 15°~45°, the target damage is severe.
Online since: December 2016
Authors: Jian Wei Huang, Jonathan Davis
Literature review showed that the tensile strength reduction of the GFRP bar should be governed by the sustained stress level in the GFRP bar.
Lee [4] reported there is an area of 3.5×108 m2 bridge deck in the US [4], 86% of which are made of cast-in-place concrete deck on the basis of the National Bridge Inventory (NBI) data [4].
In order to account for the potential strength reductions due to material degradation over time in concrete, an environmental reduction factor (ERF) is specified in ACI 440.1R-06 [2].
Recent researches showed that a 20% sustained stress could lead to a significant strength reduction of the GFRP bar in moist concrete under elevated temperatures [10, 11].
Aboutaha, Environmental reduction factors for GFRP bars used as concrete reinforcement: new scientific approach, J.
Lee [4] reported there is an area of 3.5×108 m2 bridge deck in the US [4], 86% of which are made of cast-in-place concrete deck on the basis of the National Bridge Inventory (NBI) data [4].
In order to account for the potential strength reductions due to material degradation over time in concrete, an environmental reduction factor (ERF) is specified in ACI 440.1R-06 [2].
Recent researches showed that a 20% sustained stress could lead to a significant strength reduction of the GFRP bar in moist concrete under elevated temperatures [10, 11].
Aboutaha, Environmental reduction factors for GFRP bars used as concrete reinforcement: new scientific approach, J.
Online since: November 2009
Authors: Shamil Kh. Mukhtarov
The duplex (+) NS alloys
demonstrated very high room-temperature strength after MIF, at that the reduction of ductility.
Annealing of NS alloy at 600°C for 2 hours provides some enhancement of room-temperature strength and reduces plasticity, the data being in conformity with the hardness values reported in [5,10].
This path reduction proves that a smaller area of fracture surfaces and consequently less work is needed for crack growth.
With the reduction in grain size, the SP temperature decreases.
A finer and more uniform structure achieved in INCO 718 billets provides the reduction of the difference in wall thickness of parts during forming operations [8].
Annealing of NS alloy at 600°C for 2 hours provides some enhancement of room-temperature strength and reduces plasticity, the data being in conformity with the hardness values reported in [5,10].
This path reduction proves that a smaller area of fracture surfaces and consequently less work is needed for crack growth.
With the reduction in grain size, the SP temperature decreases.
A finer and more uniform structure achieved in INCO 718 billets provides the reduction of the difference in wall thickness of parts during forming operations [8].