We employed this type of travel time functions with first-in-first-out (FIFO) property to resolve dynamic traffic assignment problems, and combine OBTAIN algorithm with the algorithm of dynamic traffic assignment. We will examine the correction of test example. Here we applied this type of travel time functions showed by Carey(2003), and then combine the function with nested diagonalization algorithm of dynamic traffic assignment by Chen and Hsueh(1996). And we will convert outflow variable and number of vehicle into functions of inflow variable. After we should confirm the result if matched the FIFO condition.