Abstract: Lagrahgian analysis was first presented by Fowles et al in the early 70's and found important applications in data processing for dynamic experiments. However, the practice reveals that it sometimes leads to unreliable results. Recent years see rapid developments in this field. New ideas,methods and improvements are suggested, such as impulse time integral function, surface fit-ting, inverse method and selfrconsistency examination etc. Particularly, some remarkable progress has been made in the study of the...