A VBHF(Variable Blank Holder Force) optimization strategy was employed to determine the optimal time-variable and spatial-variable BHF trajectories,aiming at improving the formability of automobile panels with aluminu...A VBHF(Variable Blank Holder Force) optimization strategy was employed to determine the optimal time-variable and spatial-variable BHF trajectories,aiming at improving the formability of automobile panels with aluminum alloy sheet.The strategy was implemented based on adaptive simulation to calculate the critical wrinkling BHF for each segmented binder of the Numisheet' 05 deck lid in a single round of simulation.The thickness comparison of the stamped part under optimal VBHF and constant BHF shows that the variance of the four sections is decreased by 70%,44%,64% and 61%,respectively,which indicates significant improvement in thickness distribution and variation control.The investigation through strain path comparison reveals the fundamental reason of formability improvement.The study proves the applicability of the new VBHF optimization strategy to complex parts with aluminum alloy sheet.展开更多
Flipped learning is a reversal of the traditional teaching strategy, which has changed the timing of teacher＇s lectures and homework. In this revolutionary situation, the appropriateness of the before-class videos an...Flipped learning is a reversal of the traditional teaching strategy, which has changed the timing of teacher＇s lectures and homework. In this revolutionary situation, the appropriateness of the before-class videos and other materials and the arrangement of class in the classroom play an important role in the fulfillment of application of the materials. Classical TED speeches are the excellent options for English language learners＇ flipped learning. This paper tends to make a case study of the application of TED speeches into flipped learning, taking the speeches with the keyword ＂transportation＂ as an example.展开更多
基金Project(50934011) supported by the National Natural Science Foundation of ChinaProject(20080430085) supported by the China Postdoctoral Science Foundation
文摘A VBHF(Variable Blank Holder Force) optimization strategy was employed to determine the optimal time-variable and spatial-variable BHF trajectories,aiming at improving the formability of automobile panels with aluminum alloy sheet.The strategy was implemented based on adaptive simulation to calculate the critical wrinkling BHF for each segmented binder of the Numisheet' 05 deck lid in a single round of simulation.The thickness comparison of the stamped part under optimal VBHF and constant BHF shows that the variance of the four sections is decreased by 70%,44%,64% and 61%,respectively,which indicates significant improvement in thickness distribution and variation control.The investigation through strain path comparison reveals the fundamental reason of formability improvement.The study proves the applicability of the new VBHF optimization strategy to complex parts with aluminum alloy sheet.
文摘Flipped learning is a reversal of the traditional teaching strategy, which has changed the timing of teacher＇s lectures and homework. In this revolutionary situation, the appropriateness of the before-class videos and other materials and the arrangement of class in the classroom play an important role in the fulfillment of application of the materials. Classical TED speeches are the excellent options for English language learners＇ flipped learning. This paper tends to make a case study of the application of TED speeches into flipped learning, taking the speeches with the keyword ＂transportation＂ as an example.
