- An assembly line for a certain product has two stations in series. Each station has only room for a single unit of the product. If the assembly of a unit is completed at station 1, it is forwarded immediately to station 2 provided station 2 is idle; otherwise the unit remains in station 1 until station 2 becomes free. Units for assembly arrive at station 1 according to a Poisson process with rate ?, but a newly arriving unit is only accepted by station 1 when no other unit is present in station 1. Each unit rejected is handled elsewhere. The assembly times at stations 1 and 2 are exponentially distributed with respective means 1/?1 and 1/?2. Formulate a CTMC to analyze the situation at both stations. Specify the state variable(s) and the transition rate diagram.