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Online since: May 2014
Authors: Patrick da Costa, Małgorzata Adamowska, Oriana Haddad, Dominique Leguillon
The stricter environmental regulations impose a drastic reduction of vehicles emissions and a longer durability of the automotive catalyst.
Sintering occurs, leading to a reduction of the active surface (agglomeration and coalescence of small metal crystallites into larger ones) and to a decrease of the specific surface area.
The reduction of the specific surface area is more important when the duration of ageing is longer.
In the present case it was shown [13,14] that failure initiation is a sudden mechanism occurring if two conditions are fulfilled simultaneously: (i) There is enough stored energy to be consumed by fracture ( is the potential energy change prior to and following the cracks onset, the material toughness and the overall length (in 2D) of the newly created cracks) (ii) The tensile stress exceeds the tensile strength all along the presupposed cracks path ( is the tensile component of and the tensile strength) With material data extrapolated from α-alumina taking into account the high porosity of γ-alumina: 250 GPa (Young’s modulus), 0.2 (Poisson’s ratio), 0.04 MPa.mm, 400 MPa, 6 10-6 K-1 (thermal expansion), the second condition implies 0.13% (corresponding to a temperature drop of 214 K in a purely thermo-elastic behavior), no failure can be observed below this value.
However, to go further other parameters such as the volume reduction due to the change of phases of alumina will be included in the model.
Sintering occurs, leading to a reduction of the active surface (agglomeration and coalescence of small metal crystallites into larger ones) and to a decrease of the specific surface area.
The reduction of the specific surface area is more important when the duration of ageing is longer.
In the present case it was shown [13,14] that failure initiation is a sudden mechanism occurring if two conditions are fulfilled simultaneously: (i) There is enough stored energy to be consumed by fracture ( is the potential energy change prior to and following the cracks onset, the material toughness and the overall length (in 2D) of the newly created cracks) (ii) The tensile stress exceeds the tensile strength all along the presupposed cracks path ( is the tensile component of and the tensile strength) With material data extrapolated from α-alumina taking into account the high porosity of γ-alumina: 250 GPa (Young’s modulus), 0.2 (Poisson’s ratio), 0.04 MPa.mm, 400 MPa, 6 10-6 K-1 (thermal expansion), the second condition implies 0.13% (corresponding to a temperature drop of 214 K in a purely thermo-elastic behavior), no failure can be observed below this value.
However, to go further other parameters such as the volume reduction due to the change of phases of alumina will be included in the model.
Online since: July 2019
Authors: Sofia M. Costa, Raul Fangueiro, Helena Felgueiras, Diana P. Ferreira
The functionalization of several natural fibres (jute, sisal, coir, flax and cotton) with silver nanoparticles (Ag NPs) was successfully achieved using a sustainable and eco-friendly method, namely polyethylene glycol (PEG) reduction.
When the solutions became yellow the reduction of Ag ions to silver metal (Ag0) was achieved, therefore, the samples (fabrics: 5×5 cm2, average weight ~ 1.425g and yarns: average weight ~ 1.425g) were impregnated and kept overnight.
The presence of the Ag NPs onto the natural fibres was investigated by FESEM (Fig.2) and EDX analysis (data not shown).
Therefore, the intensity increase in this area of the spectra for the jute functionalized with Ag NPs and the correspondent composite (compared with jute PLA) could point to the carbonyl group formation due to the oxidation of hydroxyl groups by Ag+ ions, attesting the reduction of Ag+ to Ag0 metal on the jute surface [7].
Wilken, Towards multifunctional cellulosic fabric: UV photo-reduction and in-situ synthesis of silver nanoparticles into cellulose fabrics, Int.
When the solutions became yellow the reduction of Ag ions to silver metal (Ag0) was achieved, therefore, the samples (fabrics: 5×5 cm2, average weight ~ 1.425g and yarns: average weight ~ 1.425g) were impregnated and kept overnight.
The presence of the Ag NPs onto the natural fibres was investigated by FESEM (Fig.2) and EDX analysis (data not shown).
Therefore, the intensity increase in this area of the spectra for the jute functionalized with Ag NPs and the correspondent composite (compared with jute PLA) could point to the carbonyl group formation due to the oxidation of hydroxyl groups by Ag+ ions, attesting the reduction of Ag+ to Ag0 metal on the jute surface [7].
Wilken, Towards multifunctional cellulosic fabric: UV photo-reduction and in-situ synthesis of silver nanoparticles into cellulose fabrics, Int.
Online since: December 2012
Authors: A. Rempp, M. Widmann, R. Gadow, A. Killinger
Gadow a
a IFKB, University of Stuttgart, Stuttgart
b WITTENSTEIN bastian GmbH, Fellbach
Abstract
For the reduction or complete compensation of grease and lubricants in mechanical engineering, special combined coatings for machine components with extended tribological and chemical properties have been developed.
For tribological applications the reduction and replacement of lubricants, e.g. mineral oils and grease, is an important issue.
Reduction of service and maintenance costs is another motivation for the process and product development.
Table 3 shows data of the applied spray powders.
Figure 5: Cross section of a metal/MoS2 lubricant lacquer composite layer before (A) and after (B) testing As shown in Figure 5 B there is still a thin film of lubricant lacquer present at the sliding interface which causes reduction of the shear forces and prevents opposing asperities from coming into direct contact.
For tribological applications the reduction and replacement of lubricants, e.g. mineral oils and grease, is an important issue.
Reduction of service and maintenance costs is another motivation for the process and product development.
Table 3 shows data of the applied spray powders.
Figure 5: Cross section of a metal/MoS2 lubricant lacquer composite layer before (A) and after (B) testing As shown in Figure 5 B there is still a thin film of lubricant lacquer present at the sliding interface which causes reduction of the shear forces and prevents opposing asperities from coming into direct contact.
Online since: October 2014
Authors: Shahrul Kamaruddin, Norizah Mohamad, Untung Setiyo Purwanto
A survey method was followed to collect data using a single respondent design.
Despite different concepts and mix results regarding the performance implication of manufacturing flexibility, this study puts forward the following working hypotheses: H1: Manufacturing flexibility is positively associated with the operational performance of manufacturing SMEs H2: Dimensions in manufacturing flexibility are positively associated with dimensions in the operational performance of manufacturing SMEs Methodology This study followed a survey method to collect data pertaining to the phenomena of manufacturing flexibility and operational performance in Indonesian manufacturing SMEs and applied a single respondent design.
The results of the MRA (presented in Fig. 2) confirmed that machine flexibility (p<0.01), product flexibility (p<0.01), and labor flexibility (p<0.01) are positively and significantly related to manufacturing cost reduction.
In particular, machine flexibility (β = 0.339) was found to have a greater impact on the manufacturing cost reduction, followed by product flexibility and labor flexibility.
Despite different concepts and mix results regarding the performance implication of manufacturing flexibility, this study puts forward the following working hypotheses: H1: Manufacturing flexibility is positively associated with the operational performance of manufacturing SMEs H2: Dimensions in manufacturing flexibility are positively associated with dimensions in the operational performance of manufacturing SMEs Methodology This study followed a survey method to collect data pertaining to the phenomena of manufacturing flexibility and operational performance in Indonesian manufacturing SMEs and applied a single respondent design.
The results of the MRA (presented in Fig. 2) confirmed that machine flexibility (p<0.01), product flexibility (p<0.01), and labor flexibility (p<0.01) are positively and significantly related to manufacturing cost reduction.
In particular, machine flexibility (β = 0.339) was found to have a greater impact on the manufacturing cost reduction, followed by product flexibility and labor flexibility.
Online since: April 2019
Authors: Roman Peleshchak, Oleh Kuzyk, Olesya Dan'kiv
It is established that ultrasonic treatment of the semiconductor in the process of formation of an ensemble of nanoclusters leads to reduction of dispersion of their sizes.
In the framework of this model, a possibility of the ultrasound-stimulated the size dispersion reduction of strained InAs/GaAs quantum dots doped with an isovalent impurity are analyzed.
The theory explained experimental data on the creation of an array of uniform InAs QDs doped with Bi [12].
Numerical calculations were carried out for the following parameters: w = 1011 s-1; e0 = 0,00001; tdi = 0,001 ms; K = 6500 eV/nm3; cl = 3500 m/s; ri(Ga3+) = 0,062 nm; ri(In3+) = 0,092 nm; ri(As3+) = 0,069 nm; ri(Bi3+) = 0,12 nm; ri(Sb3+) = 0,082 nm; ri(P3+) = 0,044 nm; cm2/s;6 cm2/s.19 There are no data in the scientific literature concerning the temperature dependences of the diffusion coefficients for Bi and Sb in InAs.
The obtained results qualitatively agree with the experimental data of Ref. [11].
In the framework of this model, a possibility of the ultrasound-stimulated the size dispersion reduction of strained InAs/GaAs quantum dots doped with an isovalent impurity are analyzed.
The theory explained experimental data on the creation of an array of uniform InAs QDs doped with Bi [12].
Numerical calculations were carried out for the following parameters: w = 1011 s-1; e0 = 0,00001; tdi = 0,001 ms; K = 6500 eV/nm3; cl = 3500 m/s; ri(Ga3+) = 0,062 nm; ri(In3+) = 0,092 nm; ri(As3+) = 0,069 nm; ri(Bi3+) = 0,12 nm; ri(Sb3+) = 0,082 nm; ri(P3+) = 0,044 nm; cm2/s;6 cm2/s.19 There are no data in the scientific literature concerning the temperature dependences of the diffusion coefficients for Bi and Sb in InAs.
The obtained results qualitatively agree with the experimental data of Ref. [11].
Online since: May 2015
Authors: Yasunori Kobori, Ramin Khatami, Haruo Kobayashi
This can be used as an EMI reduction technique [3]-[10].
Afterward, we present applications of the proposed DTC to SSCG for EMI reduction.
Data conversion in theory is simply the process of working with signals in different domains.
Temes, Understanding Delta-Sigma Data Converters, IEEE Press (2005)
Iijima, "Spread-Spectrum Clocking in Switching Regulators for EMI Reduction", IEICE Trans.
Afterward, we present applications of the proposed DTC to SSCG for EMI reduction.
Data conversion in theory is simply the process of working with signals in different domains.
Temes, Understanding Delta-Sigma Data Converters, IEEE Press (2005)
Iijima, "Spread-Spectrum Clocking in Switching Regulators for EMI Reduction", IEICE Trans.
Online since: August 2013
Authors: Ren Qiang Lu
Taking the water quality monitoring data of Tianjin’s coastal marine as an example, firstly, the high-dimension water quality data were mapped to the two-dimension plane by nonlinear mapping method.
Data and methods Based data In this paper, the Tianjin’s coastal marine were taking as an example, which includes 4 functional areas and 20 monitoring points.
Firstly, the standardized method was used to converse the observational data to avoid the magnitude difference of observational data.
Taking the standard values of the four categories coastal water quality and the monitoring data of the 20 monitoring points as the data matrix.
Then the data matrix was changed by the nonlinear mapping method.
Data and methods Based data In this paper, the Tianjin’s coastal marine were taking as an example, which includes 4 functional areas and 20 monitoring points.
Firstly, the standardized method was used to converse the observational data to avoid the magnitude difference of observational data.
Taking the standard values of the four categories coastal water quality and the monitoring data of the 20 monitoring points as the data matrix.
Then the data matrix was changed by the nonlinear mapping method.
Online since: April 2012
Authors: Norhamidi Muhamad, Baba M. Deros, Ahmad Zakaria, Nagur Aziz Kamal Bashah, Khairul Za’im Kamarulzaman, Achmed Mobin, Mohd Safuan Mohd Abdul Lazat
On the other hand, the numerical simulation method involves commercial FEM software supported by empirical data.
METHODOLOGY Sample data collection.
The data of dependent or criterion variable is examined to determine the relationship to any other independent or predictor variables [8].
While in MR model, the prediction works with identifying the trend of the output data.
As for FE Model, the unreliable springback values predicted could be attributed to the fact that material parameter were obtained from manufacturer data rather than from own tensile test.
METHODOLOGY Sample data collection.
The data of dependent or criterion variable is examined to determine the relationship to any other independent or predictor variables [8].
While in MR model, the prediction works with identifying the trend of the output data.
As for FE Model, the unreliable springback values predicted could be attributed to the fact that material parameter were obtained from manufacturer data rather than from own tensile test.
Online since: February 2023
Authors: R.S. Ponmagal, S. Priya
Based on the encoded data, that is functioned from length of data and for this purpose padding is arranged to reduce the noise and unused data.
Those attacks can be of any security issues such as services, data bytes and so on.
The AE layer performs well in recognizing the patterns of intruders, diagnosing the faults caused by attackers, and learning features fast using dimensionality reduction and data denoising techniques in the IDS.
The encoder can compress the original data from the input layer and the decoder can decompress back to relatively close original data.
Step d: Data extraction from the input features Step e: Create the encoding from the length of embedded information Step f: Convert the unsupervised data into proper document form to decode the data Step g: Optimize the data using genetic algorithm Step h: Set the rate for the learning process using the low detection value Step i: Convert the input to sequence of vector Step j: Document classification using the NRNN-AE techniques Step k: Stop.
Those attacks can be of any security issues such as services, data bytes and so on.
The AE layer performs well in recognizing the patterns of intruders, diagnosing the faults caused by attackers, and learning features fast using dimensionality reduction and data denoising techniques in the IDS.
The encoder can compress the original data from the input layer and the decoder can decompress back to relatively close original data.
Step d: Data extraction from the input features Step e: Create the encoding from the length of embedded information Step f: Convert the unsupervised data into proper document form to decode the data Step g: Optimize the data using genetic algorithm Step h: Set the rate for the learning process using the low detection value Step i: Convert the input to sequence of vector Step j: Document classification using the NRNN-AE techniques Step k: Stop.
Online since: December 2015
Authors: Chanida Soontornkallapaki, Naritsara Amhae, Wichet Lamai, Akkarat Wongkaew
Band gap energy of each film was calculated from the transmittance data.
This may due to the reduction of band gap energy in the presence of ZnO in TiO2/SiO2 films to 2.41 eV and the roughness of the film.
The data of absorbance and transmission of thin films from UV-Vis spectrophotometer are related to band gap energy of the films [10].
The band gap energy of the film was estimated from absorption and transmission data.
The reduction of band gap energy induces the superhydrophilicity with the excitation of low energy source (sunlight).
This may due to the reduction of band gap energy in the presence of ZnO in TiO2/SiO2 films to 2.41 eV and the roughness of the film.
The data of absorbance and transmission of thin films from UV-Vis spectrophotometer are related to band gap energy of the films [10].
The band gap energy of the film was estimated from absorption and transmission data.
The reduction of band gap energy induces the superhydrophilicity with the excitation of low energy source (sunlight).