An elevator operator is considering several changes to his grain unloading facilities and thus wants to simulate the existing system and the proposed changes. On an average year he expects approximately 12.5 loads of grain per hour with arrival of loads of grain having an exponential distribution. Allowing each time unit to represent a second, the time between arrivals is EXPON(3600/12.5)=EXPON(288). Once a load of grain arrives it waits to have the moisture checked and the weight of the load determined. This activity is lognormally distributed with a mean of 2 minutes and a standard deviation of 1 minute. Once this occurs, the load of grain is unloaded. Unloading time is exponentially distributed with a mean of 15 loads/hour. The elevator is open 10 hours each day.
The following SLAM model was developed to describe the situation described above.
GEN, ENGEL, ELEVATOR, 11/20/94,5,Y,Y,Y/Y,N,Y/1,72; LIMITS,6,12,100; NETWORK; CREATE, EXPON(288); WEIGHT QUEUE(1); ACTIVITY(1)/1,RLOGN(120.,60.); UNLOAD QUEUE(2),,6,BLOCK; ACTIVITY(1)/2,EXPON(240); TERMINATE; ENDNETWORK INITIALIZE,0,36000; FIN;
The above SLAM statements are described in more detail in the introduction to SLAM II document.
The above SLAM code was run using the approach described in the document describing how to run SLAM. The results of the simulation are found in this document along with a discussion of the output.