Operations Research Models and Methods / Computation

Queueing Add-in


Adding a Queue

 

  To add a queueing model on the worksheet, place the cursor at a cell where the model is to be described and select Add Queue from the menu. The dialog box below allows entry of the parameters of the model. The interarrival and service distributions are assumed to be Exponential, so no entry is required regarding distributions. Specify the name, arrival rate, service rate and number of channels. If the queue is finite, check the appropriate box and enter the maximum number in the system (the maximum number in both queue and service). If the arrival population is finite, check the box and enter the number in the population. If the replication entry is greater than 1, the number entered determines the number of queueing models put on the worksheet. This is useful when comparing queues with different sets of parameters.

The arrival rate parameter is the arrival rate when the system is empty. For a finite calling population, this is N*(lambda), where N is the number in the population and lambda is the arrival rate for each individual. For an infinite calling population, the arrival rate does not depend on the number in the system, so the arrival rate is the arrival rate into the system.

The check boxes on the dialog determine optional presentation of the steady state results. Checking the "show titles" box causes titles to be added to the worksheet. When defining a series of queueing models in sequential cells, it is useful to show the titles for the first model, and then skip the titles for the remaining models.

 
Queueing Results

Operations Research Models and Methods
by Paul A. Jensen and Jon Bard, University of Texas, Copyright by the Authors