The Experts below are selected from a list of 1142055 Experts worldwide ranked by ideXlab platform
Wiesław J. Staszewski - One of the best experts on this subject based on the ideXlab platform.
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cointegration approach for Temperature Effect compensation in lamb wave based damage detection
Smart Materials and Structures, 2013Co-Authors: Phong B Dao, Wiesław J. StaszewskiAbstract:Lamb waves are often used in smart structures with integrated, low-profile piezoceramic transducers for damage detection. However, it is well known that the method is prone to contamination from a variety of interference sources including environmental and operational conditions. The paper demonstrates how to remove the undesired Temperature Effect from Lamb wave data. The method is based on the concept of cointegration that is partially built on the analysis of the non-stationary behaviour of time series. Instead of directly using Lamb wave responses for damage detection, two approaches are proposed: (i) analysis of cointegrating residuals obtained from the cointegration process of Lamb wave responses, (ii) analysis of stationary characteristics of Lamb wave responses before and after cointegration. The method is tested on undamaged and damaged aluminium plates exposed to Temperature variations. The experimental results show that the method can: isolate damage-sensitive features from Temperature variations, detect the existence of damage and classify its severity.
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Temperature Effect modelling of piezoceramic transducers used for lamb wave propagation in damage detection applications
Proceedings of SPIE, 2013Co-Authors: Piotr Kijanka, Pawel Packo, Wiesław J. StaszewskiAbstract:Although damage detection using Lamb waves has been investigated for many years, real engineering applications are limited due to practical aspects related to implementation. Temperature Effect is one of the major problems. It is well known that Temperature variations influence Lamb wave propagation response parameters. In practice it is important to compensate for this Effect. Experimental tests are often required to understand how Temperature influences wave propagation. Numerical simulation can ease this task preventing many time-consuming experiments. Simulated Lamb wave responses can be used to develop new methods for Temperature compensation. The Effect of Temperature variations on piezoceramic transducer responses is investigated using finite element modelling. The model takes into account Temperature-dependent physical properties of low-profile PZT transducers and transducer bonding layers. The model is used to predict the S 0 and A 0 Lamb response in aluminium plate for the Temperature range from -60 to +40°C. The study shows relevant changes in Lamb wave amplitude response caused by Temperature fluctuations. This approach can provide the basis for Temperature compensation in ultrasonic guided wave damage detection systems used for structural health monitoring applications.
P G Ranjith - One of the best experts on this subject based on the ideXlab platform.
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Temperature Effect on the thermal conductivity of black coal
Journal of Chemical & Engineering Data, 2018Co-Authors: Ada E Ramazanova, Ilmutdin M Abdulagatov, P G RanjithAbstract:The guarded parallel-plate technique was employed on a black coal sample for an accurate measurement of the thermal conductivity over the Temperature range from 298 to 496 K. The combined expanded uncertainties of the Temperature (T) and thermal-conductivity (λ) measurements at the 95% confidence level with a coverage factor of k = 2 are estimated to be 20 mK and 5%, respectively. It was experimentally observed that the measured thermal conductivity (λ) of the wet and dry coal samples increases with Temperature passes through a maximum around 390 K, and then it decreases gradually at higher Temperatures. We attribute this maximum to the evolution of the volatile matter (VM) (devolatilazation) and aromatization of the carbon (pyrolysis), which is known to occur under heat treatment, and therefore, tends to increase the thermal conductivity. Over the experimental Temperature range, the measured thermal-conductivity varied from 0.341 to 0.497 W·m–1·K–1 for wet coal samples before thermal treatment and from 0...
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investigation of Temperature Effect on permeability of naturally fractured black coal for carbon dioxide movement an experimental and numerical study
Fuel, 2012Co-Authors: M S A Perera, P G Ranjith, S K Choi, David AireyAbstract:Abstract Very deep coal seams which are unlikely to be mined may be considered for CO 2 sequestration. The main objective of this study is to investigate the Effect of Temperature on the permeability of naturally fractured coal. Permeability tests were conducted on naturally fractured bituminous coal samples using high pressure triaxial equipment for five different injecting pressures (8–13 MPa) under two different confinements (20 and 24 MPa) and five different Temperatures (25–70 °C). The experimental data were then used to develop an appropriate numerical model using the COMET 3 simulator to model the Temperature Effect on permeability at Temperatures up to 200 °C. According to the measured permeability values and the developed lab-scale model, there is a clear increase in CO 2 permeability with increasing Temperature for any confining pressure at high injecting pressures (more then 10 MPa). However, for low injecting pressures (less than 9 MPa) Temperature Effect is not so much. With increasing injecting pressure, CO 2 permeability decreases at low Temperatures (less than around 40 °C), and increases at high Temperatures (more than 50 °C). Interestingly, the Temperature Effect on permeability is significant only up to around 90 °C condition within the 25–200 °C Temperature limit. These observations are related with the sorption behavior of the adsorbing CO 2 during the injection. However, there is no noticeable Temperature Effect on N 2 permeability as it does not create any swelling Effect in coal matrix.
Yw Chang - One of the best experts on this subject based on the ideXlab platform.
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Temperature Effect on twin formation kinetics and deformation behavior of Fe-18Mn-0.6C TWIP steel
'Springer Science and Business Media LLC', 2019Co-Authors: Je Jung, Park J, Js Kim, Jb Jeon, Sk Kim, Yw ChangAbstract:Temperature Effect on deformation behavior has been investigated in relation to formation kinetics of twins in a Fe-18Mn-0.6C TWIP steel. Total elongation was found to reach a maximum value of 88% at 200 A degrees C and then decreased continuously with the increase in test Temperature from 300 A degrees C up to 600 A degrees C. This reversed Temperature dependence on ductility could be attributed to the formation kinetics of deformation twins, as was prescribed by an internal variable theory of inelastic deformation. It was found that twins became more difficult to form at higher Temperatures due to insufficient internal strain energy accumulated to reduce ductility progressively in this Temperature range. Dislocation glide mechanism became, however, dominant at higher Temperatures above 600 A degrees C to increase total elongation following the usual Temperature dependence. Finally the stacking fault energy was related with the stability parameter, beta, used in the transformation kinetics relation.13
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Temperature Effect on twin formation kinetics and deformation behavior of Fe-18Mn-0.6C TWIP steel
'Springer Science and Business Media LLC', 2019Co-Authors: Je Jung, Park J, Js Kim, Jb Jeon, Sk Kim, Yw ChangAbstract:Temperature Effect on deformation behavior has been investigated in relation to formation kinetics of twins in a Fe-18Mn-0.6C TWIP steel. Total elongation was found to reach a maximum value of 88% at 200 A degrees C and then decreased continuously with the increase in test Temperature from 300 A degrees C up to 600 A degrees C. This reversed Temperature dependence on ductility could be attributed to the formation kinetics of deformation twins, as was prescribed by an internal variable theory of inelastic deformation. It was found that twins became more difficult to form at higher Temperatures due to insufficient internal strain energy accumulated to reduce ductility progressively in this Temperature range. Dislocation glide mechanism became, however, dominant at higher Temperatures above 600 A degrees C to increase total elongation following the usual Temperature dependence. Finally the stacking fault energy was related with the stability parameter, beta, used in the transformation kinetics relation.1137sciescopuskc
Phong B Dao - One of the best experts on this subject based on the ideXlab platform.
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cointegration approach for Temperature Effect compensation in lamb wave based damage detection
Smart Materials and Structures, 2013Co-Authors: Phong B Dao, Wiesław J. StaszewskiAbstract:Lamb waves are often used in smart structures with integrated, low-profile piezoceramic transducers for damage detection. However, it is well known that the method is prone to contamination from a variety of interference sources including environmental and operational conditions. The paper demonstrates how to remove the undesired Temperature Effect from Lamb wave data. The method is based on the concept of cointegration that is partially built on the analysis of the non-stationary behaviour of time series. Instead of directly using Lamb wave responses for damage detection, two approaches are proposed: (i) analysis of cointegrating residuals obtained from the cointegration process of Lamb wave responses, (ii) analysis of stationary characteristics of Lamb wave responses before and after cointegration. The method is tested on undamaged and damaged aluminium plates exposed to Temperature variations. The experimental results show that the method can: isolate damage-sensitive features from Temperature variations, detect the existence of damage and classify its severity.
Je Jung - One of the best experts on this subject based on the ideXlab platform.
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Temperature Effect on twin formation kinetics and deformation behavior of Fe-18Mn-0.6C TWIP steel
'Springer Science and Business Media LLC', 2019Co-Authors: Je Jung, Park J, Js Kim, Jb Jeon, Sk Kim, Yw ChangAbstract:Temperature Effect on deformation behavior has been investigated in relation to formation kinetics of twins in a Fe-18Mn-0.6C TWIP steel. Total elongation was found to reach a maximum value of 88% at 200 A degrees C and then decreased continuously with the increase in test Temperature from 300 A degrees C up to 600 A degrees C. This reversed Temperature dependence on ductility could be attributed to the formation kinetics of deformation twins, as was prescribed by an internal variable theory of inelastic deformation. It was found that twins became more difficult to form at higher Temperatures due to insufficient internal strain energy accumulated to reduce ductility progressively in this Temperature range. Dislocation glide mechanism became, however, dominant at higher Temperatures above 600 A degrees C to increase total elongation following the usual Temperature dependence. Finally the stacking fault energy was related with the stability parameter, beta, used in the transformation kinetics relation.13
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Temperature Effect on twin formation kinetics and deformation behavior of Fe-18Mn-0.6C TWIP steel
'Springer Science and Business Media LLC', 2019Co-Authors: Je Jung, Park J, Js Kim, Jb Jeon, Sk Kim, Yw ChangAbstract:Temperature Effect on deformation behavior has been investigated in relation to formation kinetics of twins in a Fe-18Mn-0.6C TWIP steel. Total elongation was found to reach a maximum value of 88% at 200 A degrees C and then decreased continuously with the increase in test Temperature from 300 A degrees C up to 600 A degrees C. This reversed Temperature dependence on ductility could be attributed to the formation kinetics of deformation twins, as was prescribed by an internal variable theory of inelastic deformation. It was found that twins became more difficult to form at higher Temperatures due to insufficient internal strain energy accumulated to reduce ductility progressively in this Temperature range. Dislocation glide mechanism became, however, dominant at higher Temperatures above 600 A degrees C to increase total elongation following the usual Temperature dependence. Finally the stacking fault energy was related with the stability parameter, beta, used in the transformation kinetics relation.1137sciescopuskc
