報告承辦單位: 數學與統計學院
報告內容: Dynamics of Time-Delayed Nonlinear Systems
報告人姓名:季進臣
報告人所在單位: 澳大利亞悉尼科技大學
報告人職稱/職務及學術頭銜: 副教授,博導
報告時間: 2019年1月18日 周五上午10:30
報告地點: 理科樓A419
報告人簡介: 季進臣現為悉尼科技大學機械與機電工程學院副教授。他是國際公認的非線性動力學、分岔控制、振動和非線性工程系統控制領域的專家。在國際頂級SCI期刊發表論文85余篇。他參與了由政府各資助機構資助的各種研究項目。他的研究吸引了超過310萬澳元的外部資金。
季進臣是《International Journal of Bifurcation and Chaos》等兩份國際期刊的副主編。此外，他亦是澳洲、香港及歐洲科研項目申請的評審人。他曾擔任國際會議主席，并在許多重要的國際會議上發表了他的研究成果。他是第十八屆亞太振動大會(www.APVC2019.org)組委會主席，會議將于2019年11月在澳大利亞悉尼舉行。
報告摘要：Time delay describes a situation that the present state depends on the state at previous times and can often be caused by the delayed reaction in sensors and actuators. Time delays have been found to exist in a number of engineering systems, for examples, magnetic bearing systems, maglev trains, controlled mechanical systems with delayed feedback, cold rolling mills, vehicle’s suspension system, rotating cutting and milling machines, etc. Existence of time delays in nonlinear mechanical systems can change the local stability of the trivial equilibrium of the corresponding autonomous system and induce complex dynamic behaviour in the non-autonomous systems.
This seminar will first discuss the practical examples of engineering systems involving time delay, and then the stability and dynamics of time-delayed nonlinear systems following Hopf bifurcations of the trivial equilibriums. The nonlinear systems include magnetic bearing systems, a van der Pol-Duffing oscillator with feedback control, and a quadratic nonlinear oscillator with feedback control. The secondary resonance response of the time-delayed nonlinear oscillator following two-to-one resonant Hopf bifurcations will also be discussed.
