Documents disponibles écrits par cet auteur

Active control of vehicle transient powertrain noise using a twin-FXLMS algorithm / Duan, Jie in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 133 N° 3 (Mai 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 3 (Mai 2011) . - 04 p. Titre : Active control of vehicle transient powertrain noise using a twin-FXLMS algorithm Type de document : texte imprimé Auteurs : Duan, Jie, Auteur ; Li, Mingfeng, Auteur ; Teik-Cheng Lim, Auteur Année de publication : 2011 Article en page(s) : 04 p. Note générale : Systèmes dynamiques Langues : Anglais (eng) Mots-clés : Active  noise  control  FXLMS  algorithm  Feedforward  control  Powertrain  noise Index. décimale : 629.8 Résumé : Powertrain noise is a major component of vehicle interior noise and thus has a significant effect on the overall sound quality. It is typically dominated by harmonics in the lower audible frequency range, which are directly related to the engine firing orders. In order to achieve a more comfortable environment and pleasing driving experience, an active noise control (ANC) applying advanced filtered-x least mean squares (FXLMS) algorithm is employed to reduce the vehicle interior noise by targeting these harmonics. The proposed ANC system is designed to control multiple orders of the engine noise response simultaneously. It is also uniquely formulated with a twin-FXLMS algorithm to prevent harmonic interference that often resulted in overshoot at some adjacent orders, especially at low engine speed range where the reference sinusoids are close together. In fact, the interference issue is one of the critical problems that previously plagued the use of the conventional FXLMS algorithm. The basic design of the twin-FXLMS algorithm splits the adaptive filter into two sets. This allows different sum of reference sinusoids to be fed into each adaptive filter in order to widen the frequency separation between two adjacent harmonics. Finally, the performances of proposed twin-FXLMS are validated by numerical simulations. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] [article] Active control of vehicle transient powertrain noise using a twin-FXLMS algorithm [texte imprimé] / Duan, Jie, Auteur ; Li, Mingfeng, Auteur ; Teik-Cheng Lim, Auteur . - 2011 . - 04 p. Systèmes dynamiques Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 3 (Mai 2011) . - 04 p. Mots-clés : Active  noise  control  FXLMS  algorithm  Feedforward  control  Powertrain  noise Index. décimale : 629.8 Résumé : Powertrain noise is a major component of vehicle interior noise and thus has a significant effect on the overall sound quality. It is typically dominated by harmonics in the lower audible frequency range, which are directly related to the engine firing orders. In order to achieve a more comfortable environment and pleasing driving experience, an active noise control (ANC) applying advanced filtered-x least mean squares (FXLMS) algorithm is employed to reduce the vehicle interior noise by targeting these harmonics. The proposed ANC system is designed to control multiple orders of the engine noise response simultaneously. It is also uniquely formulated with a twin-FXLMS algorithm to prevent harmonic interference that often resulted in overshoot at some adjacent orders, especially at low engine speed range where the reference sinusoids are close together. In fact, the interference issue is one of the critical problems that previously plagued the use of the conventional FXLMS algorithm. The basic design of the twin-FXLMS algorithm splits the adaptive filter into two sets. This allows different sum of reference sinusoids to be fed into each adaptive filter in order to widen the frequency separation between two adjacent harmonics. Finally, the performances of proposed twin-FXLMS are validated by numerical simulations. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]

In-plane stiffness of semiauxetic laminates / Teik-Cheng Lim in Journal of engineering mechanics, Vol. 136 N° 9 (Septembre 2010) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 136 N° 9 (Septembre 2010) . - pp. 1176-1180 Titre : In-plane stiffness of semiauxetic laminates Type de document : texte imprimé Auteurs : Teik-Cheng Lim, Auteur Article en page(s) : pp. 1176-1180 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Composite  materials  Laminates  Stiffness  Young's  modulus. Résumé : In this note it is shown that the combination of conventional laminas (possessing positive Poisson's ratio) and auxetic laminas (possessing negative Poisson's ratio) gives rise to effective in-plane composite laminate Young's modulus that surpasses the rule-of-mixture formula. To enable comparison between the developed model with the rule-of-mixture, the former is presented in such a way that two correction functions exist distinctively for multiplication into the two terms of the rule-of-mixture formula. Each of the two correction functions reduces to a minimum of 1 when all laminas possess equal Poisson's ratio, and the correction functions are greater than one when there exists mismatch in the Poisson's ratios among the laminas in the laminate. Plotted results show that the overshooting of the laminate's effective in-plane modulus is significant for semiauxetic laminates but not for conventional and fully auxetic materials. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...] [article] In-plane stiffness of semiauxetic laminates [texte imprimé] / Teik-Cheng Lim, Auteur . - pp. 1176-1180. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 136 N° 9 (Septembre 2010) . - pp. 1176-1180 Mots-clés : Composite  materials  Laminates  Stiffness  Young's  modulus. Résumé : In this note it is shown that the combination of conventional laminas (possessing positive Poisson's ratio) and auxetic laminas (possessing negative Poisson's ratio) gives rise to effective in-plane composite laminate Young's modulus that surpasses the rule-of-mixture formula. To enable comparison between the developed model with the rule-of-mixture, the former is presented in such a way that two correction functions exist distinctively for multiplication into the two terms of the rule-of-mixture formula. Each of the two correction functions reduces to a minimum of 1 when all laminas possess equal Poisson's ratio, and the correction functions are greater than one when there exists mismatch in the Poisson's ratios among the laminas in the laminate. Plotted results show that the overshooting of the laminate's effective in-plane modulus is significant for semiauxetic laminates but not for conventional and fully auxetic materials. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]