Optimization model of number of scheduled freight train formation cars
The determination of the number of formation cars is an important part of making a scheduled freight train plan, and it also has a large influence on the benefits of railway freight transportation. First, the influences that affect the number of formation cars are analyzed. Secondly, taking the maximum freight transport benefits as an objective, and comprehensively considering the primary factors that include service frequency of freight trains, section traction weight, effective length of arrival-departure tracks, and so on, this paper establishes the optimization model of the number of scheduled freight train formation cars. Finally, the solving method for the model is presented, and a case is given to show the solution process. It provides a reference for decision-makers of railway freight transportation.
Study on the Accumulation Mode of Freight Wagon in Marshalling Station
There are two different accumulation modes of freight wagon in 
marshalling station that are widely applied in the world, namely accumulation 
at fixed place and accumulation with fixed composition. By setting up a computer 
simulation model for the accumulation of freight wagon in marshalling station, 
this paper launches a thorough, deep and detailed study on the accumulation 
rule of freight wagon as well as the technical feasibility of accumulation at fixed 
place mode. The study shows that the accumulation at fixed place mode in 
marshalling station can provide a strong support for implementing freight 
transport timetable mechanism and for establishing a rapid freight forwarding 
system.
MITROP: A COMPUTER PROGRAM FOR SIMULTANEOUS OPTIMISATION OF OFFSETS, SPLITS AND CYCLE TIME
Setting traffic signals in an urban street network involves the determination of cycle time, splits of green time and offsets. Existing methods use a sequential procedure for calculating the traffic-control variables. A common cycle time is established first. Then green splits are calculated for each intersection and, finally, offsets among the signals are determined. Since these three computation stages are not really independent, the results are not necessarily optimal. Mitrop (mixed-integer traffic optimisation program) is a new computer method which is designed to optimise simultaneously all the traffic control variables in a network. Both deterministic and stochastic models are used to represent the traffic flow process. The optimisation problem is formulated in terms of mixed-integer linear programming and a globally-optimal solution is determined using IBM's MPSX optimisation system. The method was applied to several traffic signal networks and is shown to offer certain advantages over existing methods.(a) /TRRL/