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Online since: September 2011
Authors: Ghulam Yahya, M. Umer, Bilal Khan, Faraz Tahir, Zaffar Khan
The digitized data was used for development of Pro-E model.
Many lightweight materials have been used for vehicle weight reduction.
However, for the vehicle’s primary structure, carbon fiber composites offer the potential of great weight reduction without compromising structural integrity, crash worthiness and secondary processing operations.
The digitized data was used to visualize and develop Pro-E model, which was scaled up to generate CAD drawings for tool development.
Kalmbach, Weight Reduction with Composites, JEC Composites Magazine, 45 (Nov – Dec 2008) 44-45 [2] Z.M.
Many lightweight materials have been used for vehicle weight reduction.
However, for the vehicle’s primary structure, carbon fiber composites offer the potential of great weight reduction without compromising structural integrity, crash worthiness and secondary processing operations.
The digitized data was used to visualize and develop Pro-E model, which was scaled up to generate CAD drawings for tool development.
Kalmbach, Weight Reduction with Composites, JEC Composites Magazine, 45 (Nov – Dec 2008) 44-45 [2] Z.M.
Online since: January 2012
Authors: Cemail Aksel
A 3.6-fold improvement was observed in the elastic modulus data when 30% addition was made to M-30%S-ZnAl2O4 composition.
The examination of the fracture surface energy (γS) data of M-S-ZnAl2O4 composites showed that these were higher than that of M-S specimens (Fig. 6).
The critical defect size data of new compositions obtained by addition of additives to MgO increased significantly.
In general, the R thermal stress parameter data of M-S-ZnAl2O4 specimens were higher than those for M-S specimens.
The highest Rst parameter data was first reached in M-20%S-30%ZnAl2O4 composition and afterwards, in M-30%S-10%ZnAl2O4 specimen.
The examination of the fracture surface energy (γS) data of M-S-ZnAl2O4 composites showed that these were higher than that of M-S specimens (Fig. 6).
The critical defect size data of new compositions obtained by addition of additives to MgO increased significantly.
In general, the R thermal stress parameter data of M-S-ZnAl2O4 specimens were higher than those for M-S specimens.
The highest Rst parameter data was first reached in M-20%S-30%ZnAl2O4 composition and afterwards, in M-30%S-10%ZnAl2O4 specimen.
Online since: April 2014
Authors: Horst Brünnet, Dirk Bähre
If transferred to lightweight concepts wall thickness reductions as well as cost and resource savings by more than 45 % may be realized.
It also serves to make a significant contribution to weight reduction in car manufacturing and other high performance hydraulic applications.
Weight reduction with AF.
The material data was acquired by a uniaxial tensile test.
STEP 5: Reduction of surface quality in the pre-machining.
It also serves to make a significant contribution to weight reduction in car manufacturing and other high performance hydraulic applications.
Weight reduction with AF.
The material data was acquired by a uniaxial tensile test.
STEP 5: Reduction of surface quality in the pre-machining.
Online since: March 2007
Authors: Harshad K.D.H. Bhadeshia
Data from [2].
Fig. 2 illustrates the problem, that apparent increases in toughness (for example weld H5) were really associated with dramatic reductions in strength.
Data from [7].
be imagined to be three-dimensionally dissociated and nickel causes them to constrict, leading to reduction in flow stress [9].
Any increase in the nickel concentration must be balanced by a reduction in manganese in order to broaden the difference between the bainite-start and martensite-start temperatures.
Fig. 2 illustrates the problem, that apparent increases in toughness (for example weld H5) were really associated with dramatic reductions in strength.
Data from [7].
be imagined to be three-dimensionally dissociated and nickel causes them to constrict, leading to reduction in flow stress [9].
Any increase in the nickel concentration must be balanced by a reduction in manganese in order to broaden the difference between the bainite-start and martensite-start temperatures.
Online since: May 2006
Authors: Jorge Cruz Fernandes, Fernando A. Costa Oliveira, Susana Dias
The thermal stress (σt) in a rapidly cooled body can be determined according to the
expression [1]:
(1)
.
1
TE
t
ν− ∆αΨ
=σwhere ∆T is the temperature difference between the body prior to quenching and the quench
medium, α is the thermal expansion coefficient, ν is Poisson's ratio and ψ is the stress reduction
factor.
As anticipated, in the case of the dense samples, a sudden reduction in strength (from 67 to 40 MPa at ∆T = 350 K), indicative of crack growth was observed at ∆T in the range of 325-350 K.
Based on data available for dense samples [3], i.e. σf = 67 MPa, E = 96 GPa, α = 3.8x10 -6 K -1 and ν=0.30 and substituting in Eq. 1, one obtains R = 128 K, which is about three times lower than the experimental value.
For both foams, the thermal stresses lead to gradual reduction in strength, indicative of a damage accumulation process related to cracking of individual struts rather than sudden crack growth as observed for dense samples.
The data suggest that the extent of damage is little affected by the foam structure for foams with similar relative densities.
As anticipated, in the case of the dense samples, a sudden reduction in strength (from 67 to 40 MPa at ∆T = 350 K), indicative of crack growth was observed at ∆T in the range of 325-350 K.
Based on data available for dense samples [3], i.e. σf = 67 MPa, E = 96 GPa, α = 3.8x10 -6 K -1 and ν=0.30 and substituting in Eq. 1, one obtains R = 128 K, which is about three times lower than the experimental value.
For both foams, the thermal stresses lead to gradual reduction in strength, indicative of a damage accumulation process related to cracking of individual struts rather than sudden crack growth as observed for dense samples.
The data suggest that the extent of damage is little affected by the foam structure for foams with similar relative densities.
Online since: December 2010
Authors: Ming Hui Ye, Bao Cai Xu, Zhen Zhen Guan
The reaction course of chemistry nickel plating is an oxide - reduction course, the activation and reduction treatment must be carried on before chemical plating because of the positive pole oxide film Al2O3 has no oneself catalytic function.
It will have a big influence to the next step if it can not be washed uncleanly, particularly, the washing after reduction is important because it is the vital step to prevent metal particle from entering chemical plating liquid [4].
The even thickness is about 50μm when three groups of data on different parts of the layer are averaged.
The five groups of data in the different part of the tester is evened and its results show that the hardness of original tester is about HV275kg·f/mm2, while it is HV448 kgf/mm2 after chemical plating and it is HV789 kgf/mm2 after heating treatment with 400°C×1h.
It will have a big influence to the next step if it can not be washed uncleanly, particularly, the washing after reduction is important because it is the vital step to prevent metal particle from entering chemical plating liquid [4].
The even thickness is about 50μm when three groups of data on different parts of the layer are averaged.
The five groups of data in the different part of the tester is evened and its results show that the hardness of original tester is about HV275kg·f/mm2, while it is HV448 kgf/mm2 after chemical plating and it is HV789 kgf/mm2 after heating treatment with 400°C×1h.
Online since: September 2014
Authors: Yan Jun Zhang
For a given M-dimensional random vector, For its mean , the covariance can be expressed as follows:
(1)
Because of E[X]=0, covariance matrix is therefore auto-correlation matrix as follow:
(2)
Calculate eigen values of and the corresponding normalized eigenvector as the following equation:
(3)
The matrix can be expressed as follows:
(4)
With a linear combination of eigenvectors can be reconfigurable, the following formula:
(5)
Characteristics obtained through the selection of all the principal components, and in the feature extraction process, then select the main features to achieve the purpose of dimensionality reduction
Also the formula as follows: (11) Where, is the diagonal matrix element of , the contribution rate of variance as follows: (12) When is large enough, you can pre-L constitute a feature vector space as a low-dimensional projection space, thus completing the deal with dimensionality reduction.
The dimension of each original training and identification sample vector is 108, after the PCA feature extraction, the data dimension representing each flow regime is reduced to 3×12=36, finally to 1×12 after normalized, written as Principal component analysis can be carried out under the standard deviation feature extraction error, but as it relates to solving the matrix eigenvalue and eigenvector computation so great.
Using neural networks and parallel computing through the use of unsupervised learning methods self-organization can be achieved on the input data of the principal component extraction.
[2] J.Karhunen, J.Joutsensalo, “Representation and Separation of Signals Using Nonlinear PCA Type Exploring the bounds of Web latency reduction from caching and prefetching”, Learning Journal, Helsinki University of Technology, vol. 8, pp.1083-1091, 2001
Also the formula as follows: (11) Where, is the diagonal matrix element of , the contribution rate of variance as follows: (12) When is large enough, you can pre-L constitute a feature vector space as a low-dimensional projection space, thus completing the deal with dimensionality reduction.
The dimension of each original training and identification sample vector is 108, after the PCA feature extraction, the data dimension representing each flow regime is reduced to 3×12=36, finally to 1×12 after normalized, written as Principal component analysis can be carried out under the standard deviation feature extraction error, but as it relates to solving the matrix eigenvalue and eigenvector computation so great.
Using neural networks and parallel computing through the use of unsupervised learning methods self-organization can be achieved on the input data of the principal component extraction.
[2] J.Karhunen, J.Joutsensalo, “Representation and Separation of Signals Using Nonlinear PCA Type Exploring the bounds of Web latency reduction from caching and prefetching”, Learning Journal, Helsinki University of Technology, vol. 8, pp.1083-1091, 2001
Online since: June 2014
Authors: Min Xu, Chun Shan Zhao, Chun Guo Li
Statistical Analysis The data were analyzed with SPSS19.0 software.
The data are shown in Table 1.
Table 2 Cognition of pupils on the knowledge of air pollution hazards to respiratory health Awareness rate Acute harms Dyspnea 41.2% cough 34.7% asthma 23.1% Chronic harms Pharyngitis 9.7% Bronchitis 10.1% Lung cancer 5.6% Health Behaviors of Pupils in Air pollution There were 35.1 % of pupils wore masks to prevent air pollution; 29.8 % of them participated in public service activities of energy conservation and emission reduction; 6.7 % of them involved in environmental protection activities (Table 3).
Table 3 Health Behaviors of Pupils in Air pollution Percentage Wearing masks or other protection behaviors 35.1% Participating in public service activity of energy conservation and emission reduction (such as utilizing public transport and energy saving lamp) 29.8% Positively participating in environmental protection activities (such as objection to smoking and incineration) 6.7% Demand of Pupils for the Knowledge on Air Pollution In pupils’ demand of for the knowledge on air pollution, the prevention measures in air pollution ranked first, accounting for 75.9%, followed by the knowledge on common respiratory symptoms and diseases, accounting for 73.8%, then air pollution sources and its harms, accounting for 66.2%, and finally, the main components of air pollutants, accounting for 37.1%; in the demand for the learning channels, 71.2% of pupils wanted to get the knowledge of air pollution in schools, and 76.5 of them wanted to be able to participate in various environmental activities
And many pupils expressed their willingness in the contribution to the reduction of air pollution through their own actions (such as by bus, using energy-saving lamps and participating in environmental protection activities, etc.).
The data are shown in Table 1.
Table 2 Cognition of pupils on the knowledge of air pollution hazards to respiratory health Awareness rate Acute harms Dyspnea 41.2% cough 34.7% asthma 23.1% Chronic harms Pharyngitis 9.7% Bronchitis 10.1% Lung cancer 5.6% Health Behaviors of Pupils in Air pollution There were 35.1 % of pupils wore masks to prevent air pollution; 29.8 % of them participated in public service activities of energy conservation and emission reduction; 6.7 % of them involved in environmental protection activities (Table 3).
Table 3 Health Behaviors of Pupils in Air pollution Percentage Wearing masks or other protection behaviors 35.1% Participating in public service activity of energy conservation and emission reduction (such as utilizing public transport and energy saving lamp) 29.8% Positively participating in environmental protection activities (such as objection to smoking and incineration) 6.7% Demand of Pupils for the Knowledge on Air Pollution In pupils’ demand of for the knowledge on air pollution, the prevention measures in air pollution ranked first, accounting for 75.9%, followed by the knowledge on common respiratory symptoms and diseases, accounting for 73.8%, then air pollution sources and its harms, accounting for 66.2%, and finally, the main components of air pollutants, accounting for 37.1%; in the demand for the learning channels, 71.2% of pupils wanted to get the knowledge of air pollution in schools, and 76.5 of them wanted to be able to participate in various environmental activities
And many pupils expressed their willingness in the contribution to the reduction of air pollution through their own actions (such as by bus, using energy-saving lamps and participating in environmental protection activities, etc.).
Online since: October 2012
Authors: Wei Ching Yeh, Tsu Hsiao Chu
All recorded signals were acquired by InstruNet signal acquisition hardware and software for data processing.
Then a polynomial approximation of is generally defined to express the function on the basis of observation data.
Because of the reduction of the mean effect stress in the blanking process, the fracture appeared later and more slowly during application of the ultrasonic vibrations.[7] The blanking process with ultrasonic vibration not only increases the plasticity of the sheet but also extends the shear zone.
The reduction of blanking load is due to continuously alternate contact and separation by superimposing ultrasonic vibrations, considerably resulted in the decrease of friction condition between the die and the sheet.
Hutchings, Reduction of the Sliding Friction of Metals by the Application of Longitudinal or Transverse Ultrasonic Vibration, Tribology International, 37(2004) 833–840
Then a polynomial approximation of is generally defined to express the function on the basis of observation data.
Because of the reduction of the mean effect stress in the blanking process, the fracture appeared later and more slowly during application of the ultrasonic vibrations.[7] The blanking process with ultrasonic vibration not only increases the plasticity of the sheet but also extends the shear zone.
The reduction of blanking load is due to continuously alternate contact and separation by superimposing ultrasonic vibrations, considerably resulted in the decrease of friction condition between the die and the sheet.
Hutchings, Reduction of the Sliding Friction of Metals by the Application of Longitudinal or Transverse Ultrasonic Vibration, Tribology International, 37(2004) 833–840
Online since: July 2015
Authors: Nancy J. Siambun, Miron Gakim, Lam Mun Khong, Jidon Janaun, Willey Liew Yun Hsien
The formation of crater-like surface suggested additional reactions of cathodic evolution of CO gas according to Eq. 5 (formation of CO through oxidation of CO32- ion) and Eq. 6 (formation of CO through reduction of CO2 and oxidation of CO32-).
The EDX elemental spectrum data (Table 1) had confirmed that carbon was the dominant element of the washed cathodic products that were deposited in K2CO3-Li2CO3, CaCO3-Li2CO3-LiCl, and CaCO3-CaCl2-KCl-LiCl electrolytes, with respective percentage of 92.01%, 89.09% and 97.96% carbon, and small amount of other elements related to the electrolytic materials.
Table 2 Electrolysis data for different salt mixtures.
The energy consumption to produce 1kg of carbon in the binary, ternary and quaternary salt mixtures in this work was more than 40kWh/kg for electrolytic reduction alone (not including the energy to melt the salt).
To visualise this figure, the energy consumption in Aluminium production is 15.6kWh/kg for electrolytic reduction [19].
The EDX elemental spectrum data (Table 1) had confirmed that carbon was the dominant element of the washed cathodic products that were deposited in K2CO3-Li2CO3, CaCO3-Li2CO3-LiCl, and CaCO3-CaCl2-KCl-LiCl electrolytes, with respective percentage of 92.01%, 89.09% and 97.96% carbon, and small amount of other elements related to the electrolytic materials.
Table 2 Electrolysis data for different salt mixtures.
The energy consumption to produce 1kg of carbon in the binary, ternary and quaternary salt mixtures in this work was more than 40kWh/kg for electrolytic reduction alone (not including the energy to melt the salt).
To visualise this figure, the energy consumption in Aluminium production is 15.6kWh/kg for electrolytic reduction [19].