Documents disponibles écrits par cet auteur

Control design for the active stabilization of rail wheelsets / T. X. Mei in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 130 N°1 (Janvier/Fevrier 2008) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 130 N°1 (Janvier/Fevrier 2008) . - 9 p. Titre : Control design for the active stabilization of rail wheelsets Type de document : texte imprimé Auteurs : T. X. Mei, Auteur ; H. Li, Auteur Année de publication : 2008 Article en page(s) : 9 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : railway  wheelset;  stabilization  control;  feedback Résumé : Through a detailed control assessment of a conventional railway wheelset, this paper addresses some of the key design issues in the development of active primary suspensions for the stabilization control of railway vehicles. It reveals the basic feedback requirements for achieving adequate stability and hence provides a useful insight of how active controllers may be structured. For the control design, a number of factors in addition to the stabilization are considered including the actuation requirements, creep forces at the wheel-rail contact, track following as well as robustness against parameter variations. Based on the outcome of the control analysis, the study proposes a design and optimization procedure for the development of active wheelset control. The design method is applied to a two-axle vehicle in a case study, which shows that the new design approach is advantageous when compared with other design methods previously studied. En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] Control design for the active stabilization of rail wheelsets [texte imprimé] / T. X. Mei, Auteur ; H. Li, Auteur . - 2008 . - 9 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 130 N°1 (Janvier/Fevrier 2008) . - 9 p. Mots-clés : railway  wheelset;  stabilization  control;  feedback Résumé : Through a detailed control assessment of a conventional railway wheelset, this paper addresses some of the key design issues in the development of active primary suspensions for the stabilization control of railway vehicles. It reveals the basic feedback requirements for achieving adequate stability and hence provides a useful insight of how active controllers may be structured. For the control design, a number of factors in addition to the stabilization are considered including the actuation requirements, creep forces at the wheel-rail contact, track following as well as robustness against parameter variations. Based on the outcome of the control analysis, the study proposes a design and optimization procedure for the development of active wheelset control. The design method is applied to a two-axle vehicle in a case study, which shows that the new design approach is advantageous when compared with other design methods previously studied. En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]

Corrosion–erosion wear of N80 carbon steel and 316L stainless steel in saline–quartz slurry / H. Li in Materials and corrosion, Vol. 62 N° 11 (Novembre 2011) 

Public ISBD [article]  in Materials and corrosion > Vol. 62 N° 11 (Novembre 2011) . - pp. 1051–1060 Titre : Corrosion–erosion wear of N80 carbon steel and 316L stainless steel in saline–quartz slurry Type de document : texte imprimé Auteurs : H. Li, Auteur ; Y. H. Liu, Auteur ; Y. Z. Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 1051–1060 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : 3D  ultra-deep  microscopy  316lL  N80  SEM Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The corrosion–erosion behavior of carbon steel N80 and austenitic stainless 316L are investigated both in water–quartz slurry and saline–quartz slurry. The sample mass losses after each test and the roughness of sample surfaces are measured and a potentiostat is used to gain the polarization curves. The worn surfaces and the corrosion–erosion wear mechanism are analyzed using scanning electron microscopy (SEM) and 3D ultra-deep microscopy. Results show that the Ra for N80 is much larger than 316L under the same experimental condition, and the weight losses of the two materials show a similar trend except for tests with higher impact angles. The lowest Rsm for 316L matches along with the highest Rsm for N80 at the 45 min testing time. According to the obtained results of the corrosion–erosion mechanism of the N80 and 316L based on the SEM and 3D ultra-deep microscopy, the conclusion is drawn that the ploughing and crashing are the major mechanisms for the forming of surface morphologies and the mass removal. Different impact angles and materials affect the corrosion–erosion process to some extent. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201106086/abstract [article] Corrosion–erosion wear of N80 carbon steel and 316L stainless steel in saline–quartz slurry [texte imprimé] / H. Li, Auteur ; Y. H. Liu, Auteur ; Y. Z. Wang, Auteur . - 2012 . - pp. 1051–1060. Génie Mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 62 N° 11 (Novembre 2011) . - pp. 1051–1060 Mots-clés : 3D  ultra-deep  microscopy  316lL  N80  SEM Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The corrosion–erosion behavior of carbon steel N80 and austenitic stainless 316L are investigated both in water–quartz slurry and saline–quartz slurry. The sample mass losses after each test and the roughness of sample surfaces are measured and a potentiostat is used to gain the polarization curves. The worn surfaces and the corrosion–erosion wear mechanism are analyzed using scanning electron microscopy (SEM) and 3D ultra-deep microscopy. Results show that the Ra for N80 is much larger than 316L under the same experimental condition, and the weight losses of the two materials show a similar trend except for tests with higher impact angles. The lowest Rsm for 316L matches along with the highest Rsm for N80 at the 45 min testing time. According to the obtained results of the corrosion–erosion mechanism of the N80 and 316L based on the SEM and 3D ultra-deep microscopy, the conclusion is drawn that the ploughing and crashing are the major mechanisms for the forming of surface morphologies and the mass removal. Different impact angles and materials affect the corrosion–erosion process to some extent. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201106086/abstract

A rigid rectangular footing on an elastic layer / J. P. Dempsey in Géotechnique, Vol. 39 N°1 (Mars 1989) 

Public ISBD [article]  in Géotechnique > Vol. 39 N°1 (Mars 1989) . - pp. 147–152 Titre : A rigid rectangular footing on an elastic layer Type de document : texte imprimé Auteurs : J. P. Dempsey, Auteur ; H. Li, Auteur Année de publication : 2007 Article en page(s) : pp. 147–152 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Settlement  Stress  analysis  Elasticity  Soil–structure  interaction  Interaction  Bearing  capacity  Footings/foundations Note de contenu : Technical Note ISSN : 0016-8505 En ligne : http://www.icevirtuallibrary.com/content/article/10.1680/geot.1989.39.1.147 [article] A rigid rectangular footing on an elastic layer [texte imprimé] / J. P. Dempsey, Auteur ; H. Li, Auteur . - 2007 . - pp. 147–152. Génie Civil Langues : Anglais (eng) in Géotechnique > Vol. 39 N°1 (Mars 1989) . - pp. 147–152 Mots-clés : Settlement  Stress  analysis  Elasticity  Soil–structure  interaction  Interaction  Bearing  capacity  Footings/foundations Note de contenu : Technical Note ISSN : 0016-8505 En ligne : http://www.icevirtuallibrary.com/content/article/10.1680/geot.1989.39.1.147

Scheduling an unbounded batching machine with family jobs and setup times / R. Zheng in Journal of the operational research society (JORS), Vol. 63 N° 2 (Fevrier 2012) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 63 N° 2 (Fevrier 2012) . - pp. 160–167 Titre : Scheduling an unbounded batching machine with family jobs and setup times Type de document : texte imprimé Auteurs : R. Zheng, Auteur ; H. Li, Auteur ; X. Zhang, Auteur Année de publication : 2012 Article en page(s) : pp. 160–167 Note générale : Recherche opérationnelle Langues : Anglais (eng) Mots-clés : Scheduling  Batching  machine  Family  jobs  Setup  times  Dynamic  programming Index. décimale : 001.424 Résumé : We consider the problem of scheduling n jobs on an unbounded batching machine that can process any number of jobs belonging to the same family simultaneously in the same batch. All jobs in the same batch complete at the same time. Jobs belonging to different families cannot be processed in the same batch, and setup times are required to switch between batches that process jobs from different families. For a fixed number of families m, we present a generic forward dynamic programming algorithm that solves the problem of minimizing an arbitrary regular cost function in pseudopolynomial time. We also present a polynomial-time backward dynamic programming algorithm with time complexity O (mn(n/m+1)m) for minimizing any additive regular minsum objective function and any incremental regular minmax objective function. The effectiveness of our dynamic programming algorithm is shown by computational experiments based on the scheduling of the heat-treating process in a steel manufacturing plant. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n2/abs/jors2010187a.html [article] Scheduling an unbounded batching machine with family jobs and setup times [texte imprimé] / R. Zheng, Auteur ; H. Li, Auteur ; X. Zhang, Auteur . - 2012 . - pp. 160–167. Recherche opérationnelle Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 63 N° 2 (Fevrier 2012) . - pp. 160–167 Mots-clés : Scheduling  Batching  machine  Family  jobs  Setup  times  Dynamic  programming Index. décimale : 001.424 Résumé : We consider the problem of scheduling n jobs on an unbounded batching machine that can process any number of jobs belonging to the same family simultaneously in the same batch. All jobs in the same batch complete at the same time. Jobs belonging to different families cannot be processed in the same batch, and setup times are required to switch between batches that process jobs from different families. For a fixed number of families m, we present a generic forward dynamic programming algorithm that solves the problem of minimizing an arbitrary regular cost function in pseudopolynomial time. We also present a polynomial-time backward dynamic programming algorithm with time complexity O (mn(n/m+1)m) for minimizing any additive regular minsum objective function and any incremental regular minmax objective function. The effectiveness of our dynamic programming algorithm is shown by computational experiments based on the scheduling of the heat-treating process in a steel manufacturing plant. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n2/abs/jors2010187a.html