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Online since: November 2012
Authors: Dinesh Srivastava, Gautam Kumar Dey, Nachiket Keskar, Vikrant Raizada, Vaibhaw Kumar, Sanjay Kumar Jha, Nudurupati Saibaba
The flow stress data from a Gleeble machine, obtained both below β transus temperature in two phase α+β region as well as above β transus temperature in β phase region, were directly used in the FEM simulation of extrusion process, eliminating the need for any assumptions regarding material plastic flow law.
From such information, the necessary design specifications and data are obtained for optimization of the design of dies and the prediction of mechanical properties of extruded product.
For optimizing the values for heat transfer coefficient and friction coefficient for Zr-based alloys and tool steel interface, multiple combinations of convective heat transfer and friction coefficient were adopted for simulation and the ones which gave ram force profile that conformed to the actual experimental data obtained from the shop floor were taken as the optimum values.
Reduction ratio Reduction Ratio 6 (a) Reduction Ratio 8 (b) Reduction Ratio 10 (c) Reduction Ratio 12 (d) Reduction Ratio 14.4 (e) Reduction Ratio 20 (f) Figure 3: The temperature profile is seen to change with change in reduction ratio.
Effect of reduction ratio Intuitively, increasing reduction ratio should result in increase in required ram force.
From such information, the necessary design specifications and data are obtained for optimization of the design of dies and the prediction of mechanical properties of extruded product.
For optimizing the values for heat transfer coefficient and friction coefficient for Zr-based alloys and tool steel interface, multiple combinations of convective heat transfer and friction coefficient were adopted for simulation and the ones which gave ram force profile that conformed to the actual experimental data obtained from the shop floor were taken as the optimum values.
Reduction ratio Reduction Ratio 6 (a) Reduction Ratio 8 (b) Reduction Ratio 10 (c) Reduction Ratio 12 (d) Reduction Ratio 14.4 (e) Reduction Ratio 20 (f) Figure 3: The temperature profile is seen to change with change in reduction ratio.
Effect of reduction ratio Intuitively, increasing reduction ratio should result in increase in required ram force.
Online since: April 2014
Authors: Zora Jančíková, Pavel Koštial, Milena Kušnerová, Marta Harničarová, Jan Valíček, J. Zavadil
The higher reduction Δh was required, the higher was the number of passes of the sheet through the rolling stand.
The higher reduction is required, the higher will be the proof stress Rp0.2, and tensile strength Rm and also the smoother will be the forged piece surface.
Fig. 1 –Influence of tensile strength on mean arithmetic deviation of the surface profile in deep-drawing steel The diagram shows linear regressions of the measured data of the samples „C“ and „D“ with the reliability value R2 and equations of linear regression.
On the basis of identification of relations between technological parameters of the technological process we obtained from the regression analysis of experimental data the equations for the reference material KOHAL.
Table 2 presents numerically individual parameters in respect to the real measured absolute reduction ∆h.
The higher reduction is required, the higher will be the proof stress Rp0.2, and tensile strength Rm and also the smoother will be the forged piece surface.
Fig. 1 –Influence of tensile strength on mean arithmetic deviation of the surface profile in deep-drawing steel The diagram shows linear regressions of the measured data of the samples „C“ and „D“ with the reliability value R2 and equations of linear regression.
On the basis of identification of relations between technological parameters of the technological process we obtained from the regression analysis of experimental data the equations for the reference material KOHAL.
Table 2 presents numerically individual parameters in respect to the real measured absolute reduction ∆h.
Online since: May 2010
Authors: Geir Martin Haarberg, Karin Sende Osen, Egil Skybakmoen, Ole Sigmund Kjos, Ana Maria Martinez, Kevin Dring
The anode is made by
carbothermal reduction of an enriched TiO2 slag.
Data obtained by XRF analysis and given in weight %.
Data obtained by XRF analysis and given in weight %.
This is due to an "incomplete" carbothermal reduction process.
Martinez, Electrochemical Society Transactions, 16 (49) (2009) p. 229 [15] Landolt-Börnstein in Phase Equilibria, Crystallographic and Thermodynamic Data of Binary Alloys, Springer-Verlag (1998) [16] D.M.
Data obtained by XRF analysis and given in weight %.
Data obtained by XRF analysis and given in weight %.
This is due to an "incomplete" carbothermal reduction process.
Martinez, Electrochemical Society Transactions, 16 (49) (2009) p. 229 [15] Landolt-Börnstein in Phase Equilibria, Crystallographic and Thermodynamic Data of Binary Alloys, Springer-Verlag (1998) [16] D.M.
Online since: March 2011
Authors: Xiao Hui Zeng, Ling Zhou, Huang Lin Zeng
This is main issue we are interested in is knowledge simplification and reasoning decision rules from a finite data of a database of an uncertain information system.
Proof:For a knowledge uncertain system, If ,then ( 3.3 ) If the system does not exist a redundant data (i.e. no duplicates of an object, the same conditions correspond to the same result), then all of the objects of equivalent family in contained in equivalent family.
Step 1: Data normalization and discretization of attribute values in a decision information system is realized by way of methods of equal frequency, equal distance or central clustering and so on [10] so that a database of an uncertain information system is generalized.
Step 2: Based on theorem 3, examine whether the data of a comprehensive system is coordinated and the dependency property of condition attribution with decision attribution.
Based on theorem 3, it is easy to find data of CTR car database is coordinated.
Proof:For a knowledge uncertain system, If ,then ( 3.3 ) If the system does not exist a redundant data (i.e. no duplicates of an object, the same conditions correspond to the same result), then all of the objects of equivalent family in contained in equivalent family.
Step 1: Data normalization and discretization of attribute values in a decision information system is realized by way of methods of equal frequency, equal distance or central clustering and so on [10] so that a database of an uncertain information system is generalized.
Step 2: Based on theorem 3, examine whether the data of a comprehensive system is coordinated and the dependency property of condition attribution with decision attribution.
Based on theorem 3, it is easy to find data of CTR car database is coordinated.
Online since: February 2014
Authors: Guo Xiang Tong, Fang Fang Lv, Jian Tan
Research of Noise Reduction Algorithm Based on Real Time
Guoxiang Tong1, a, Fangfang Lv1, b* , Jian Tan 1, c
1School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology,Shanghai 200093,China
aemail: guoxiangtong@163.com, bemail:keykeylvjian@163.com,cemail:Taozhe58@163.com
Keywords:Noise reduction; Modified LMS; Step size; SNR; MSE; Misalignment; RNS;
Abstract.
Structure of de-noising In order to better illustrate the noise reduction effect of each modified LMS algorithm.
Then the outputted bit-stream was processed by the DSP processing system based on RNS [12] which included three parts: (1) the front part of the data conversion system that changed bit-stream to RNS; (2) the FIR filter processing module based on RNS; (3) the last part of the data conversion system that changed RNS to bit-stream.
Then the signal processed by the DSP system was operated by the D/A converter based on Delta - sigma, the data flow was converted to analog signal.
The combined system not only increased the processing speed of data, but also expanded the processing width of data, which may be achieved three times faster than the original system.
Structure of de-noising In order to better illustrate the noise reduction effect of each modified LMS algorithm.
Then the outputted bit-stream was processed by the DSP processing system based on RNS [12] which included three parts: (1) the front part of the data conversion system that changed bit-stream to RNS; (2) the FIR filter processing module based on RNS; (3) the last part of the data conversion system that changed RNS to bit-stream.
Then the signal processed by the DSP system was operated by the D/A converter based on Delta - sigma, the data flow was converted to analog signal.
The combined system not only increased the processing speed of data, but also expanded the processing width of data, which may be achieved three times faster than the original system.
Online since: May 2011
Authors: Ya Long Liao, Xi Juan Chai, Jiang Tao Li, Fu Chang Xu, Dong Bo Li
Table 3 The ingredient analysis of bornite by electron probe unit: wt%
Item
1
2
3
4
5
Average
S
27.86
27.51
27.27
28.34
26.85
27.57
Fe
17.23
16.90
17.88
16.51
16.85
17.07
Cu
54.91
55.59
54.85
55.15
56.13
55.36
3.4 Mineralogical composition of reduction products
The typically chemical composition on the aspect of iron in the final products after the copper slag was reduced with carbonthermic method at 1423 K for 4 h could be found in Table 4,the data in Table 4 was the average of ten times experiments with a scope of 100g each time.
Fig.2 was the X-ray diffraction graph of the reduction products of copper slag.
Fig. 1 XRD of copper slag before reduction Fig. 2 XRD of reduction products 3.5 Thermodynamic analysis of the modification of slag and reduction The addition of CaO or lime could tend to increase the reduction ration of iron.
Which guaranteed the reduction process go with a swing.
Sahin, B.Sirin, A reduction study of copper slag in a DC arc furnace, Scand.
Fig.2 was the X-ray diffraction graph of the reduction products of copper slag.
Fig. 1 XRD of copper slag before reduction Fig. 2 XRD of reduction products 3.5 Thermodynamic analysis of the modification of slag and reduction The addition of CaO or lime could tend to increase the reduction ration of iron.
Which guaranteed the reduction process go with a swing.
Sahin, B.Sirin, A reduction study of copper slag in a DC arc furnace, Scand.
Online since: November 2014
Authors: Ida Idayu Muhamad, Norzita Ngadi, M. Jusoh, Noor Yahida Yahya
Under this condition, the reduction of COD was achieved up to 54.24%.
RSM is a collection of mathematical and statistical techniques based on the fit of a polynomial equation to the experimental data, which must describe the behaviour of a data set with the objective of making statistical previsions [3].
STATISTICA 8.0 was employed for data analysis.
Fig. 1 a) Parity plot for percentage reduction of COD b) Pareto chart of percentage reduction of COD Interaction Effects of Variables on Percentage Reduction of COD.
The observed value of COD reduction percentage is 54.03%.
RSM is a collection of mathematical and statistical techniques based on the fit of a polynomial equation to the experimental data, which must describe the behaviour of a data set with the objective of making statistical previsions [3].
STATISTICA 8.0 was employed for data analysis.
Fig. 1 a) Parity plot for percentage reduction of COD b) Pareto chart of percentage reduction of COD Interaction Effects of Variables on Percentage Reduction of COD.
The observed value of COD reduction percentage is 54.03%.
Online since: June 2010
Authors: K.N. Anyfantis, N.G. Tsouvalis
CCM is a classical data reduction scheme for
calculating GIIc [10] using the Irwin - Kies equation.
Thus, the GII(δ*) discrete data sets were plotted for each data reduction scheme and an analytical function was used to fit the results for each case.
Fig. 9 compares the bridging laws (traction-separation laws) as inferred by CCM, CBT and CBBM data reduction schemes.
Fracture energy was measured from ENF tests with the use of three different data reduction schemes.
The obtained bridging laws exhibit the same softening behaviour, regardless the data reduction method used.
Thus, the GII(δ*) discrete data sets were plotted for each data reduction scheme and an analytical function was used to fit the results for each case.
Fig. 9 compares the bridging laws (traction-separation laws) as inferred by CCM, CBT and CBBM data reduction schemes.
Fracture energy was measured from ENF tests with the use of three different data reduction schemes.
The obtained bridging laws exhibit the same softening behaviour, regardless the data reduction method used.
Online since: September 2012
Authors: Wei Wang, You Hong Xiao, Xin Na Tian
Selective catalytic reduction (SCR) aftertreatment system has been applied to reduce Nitrogen Oxides (NOx) as a key technology.
The simulation data were shown in table 1: Table1, Simulation Data and Results M N NO2(ppm) NO(ppm) NH3(ppm) NOx conversion efficiency NH3 slip(ppm) 1 5 1 50 250 300 91.% 14 2 7 1 37.5 262.5 300 90.% 15 3 9 1 30 270 300 91.4% 12 4 9 0.8 30 270 240 76.4% 8 5 9 1.1 30 270 330 93.4% 49 Through the results of the simulation, can analysis the two factors influence on the NOx conversion efficiency and NH3 slip intuitively, the changes of m has not influence on the NOx conversion efficiency and NH3 slip, however, the changes of n has a great influence on them.
The NOx conversion efficiency has a significant reduction.
[2] Ming-Feng Hsieh, ”Control of Diesel Engine Urea Selective Catalyst Reduction Systems”.
Diesel SCR NOx Reduction and Performance on Washcoated SCR Catalysts [C].SAE, 2004-01-1293
The simulation data were shown in table 1: Table1, Simulation Data and Results M N NO2(ppm) NO(ppm) NH3(ppm) NOx conversion efficiency NH3 slip(ppm) 1 5 1 50 250 300 91.% 14 2 7 1 37.5 262.5 300 90.% 15 3 9 1 30 270 300 91.4% 12 4 9 0.8 30 270 240 76.4% 8 5 9 1.1 30 270 330 93.4% 49 Through the results of the simulation, can analysis the two factors influence on the NOx conversion efficiency and NH3 slip intuitively, the changes of m has not influence on the NOx conversion efficiency and NH3 slip, however, the changes of n has a great influence on them.
The NOx conversion efficiency has a significant reduction.
[2] Ming-Feng Hsieh, ”Control of Diesel Engine Urea Selective Catalyst Reduction Systems”.
Diesel SCR NOx Reduction and Performance on Washcoated SCR Catalysts [C].SAE, 2004-01-1293
Online since: January 2006
Authors: Yvan Houbaert, Leo A.I. Kestens, Ana Carmen C. Reis, Pablo Rodriguez-Calvillo
The volume fraction of these small equi-axed
grains increased from 19.9% after 75%reduction at 800°C to 67.8% after 75% reduction at
1.100°C.
Dynamic recrystallization (DRX), though, has not yet been reported for these alloys although the present data suggest that a DRX mechanism might be responsible for the remarkable grain refinement after relatively low amounts of strain applied at high temperatures.
Texture and orientation contrast map after PSC at 800°C and a reduction of 0.75.
Dynamic recrystallization (DRX), though, has not yet been reported for these alloys although the present data suggest that a type of dynamic recrystallization may be responsible for the remarkable grain refinement after relatively low amounts of strain applied at high temperatures.
The data of Fig. 5 do not reveal an obvious difference in texture between the recrystallised and the deformed fraction of the microstructure, although there seems to be a tendency that γfibre grains preferentially disappear from the deformed matrix.
Dynamic recrystallization (DRX), though, has not yet been reported for these alloys although the present data suggest that a DRX mechanism might be responsible for the remarkable grain refinement after relatively low amounts of strain applied at high temperatures.
Texture and orientation contrast map after PSC at 800°C and a reduction of 0.75.
Dynamic recrystallization (DRX), though, has not yet been reported for these alloys although the present data suggest that a type of dynamic recrystallization may be responsible for the remarkable grain refinement after relatively low amounts of strain applied at high temperatures.
The data of Fig. 5 do not reveal an obvious difference in texture between the recrystallised and the deformed fraction of the microstructure, although there seems to be a tendency that γfibre grains preferentially disappear from the deformed matrix.