A PASSENGER FLOW MODEL IS FORMULATED FOR TWO RAILWAY ROUTES WHICH HAVE A JUNCTION. WE SUPPOSE THE RAILWAY FARES TO BE SUM OF THE STARTING FARE AND THE FARE PROPORTIONAL TO THE TRAVEL DISTANCE. IF THE PASSENGER TRANSFERS FROM ONE RAILWAY ROUTE TO ANOTHER, HE MUST PAY THE STARTING FARE TWICE. IN THIS STUDY, WE SUPPOSE THE TRIP DENSITY TO BE THE NEGATIVE EXPONENTIAL FUNCTION OF THE TRAVEL COST. WE WILL CALCULATE THE AMOUNT OF TRIPS AND THE REVENUE OF THE RAILWAY COMPANIES, AND THEN DISCUSS THE OPTIMAL FARE SYSTEM FROM SOME POINTS OF VIEW.
