Four trucks, 1, 2, 3, and 4, are waiting on a loading dock at XYZ Company that has only a single service bay. The trucks are labeled in the order that they arrived at the dock. Assume the current time is 1:00 P.M. The times required to unload each truck and the times that the goods they contain are due in the plant are given in the following table. Truck Unloading Time (minutes) Time Material Is Due 1 20 1:25 P.M. 2 14 1:45 P.M. 35 1:50 P.M. 4 10 1:30 P.M. Determine the schedules that result for each of the rules FCFS, SPT, EDD, and CR. In each case compute the mean flow time, average tardiness, and number of tardy jobs.

Four trucks, 1, 2, 3, and 4, are waiting on a loading dock at XYZ Company that has only a single service bay. The trucks are labeled in the order that they arrived at the dock. Assume the current time is 1:00 P.M. The times required to unload each truck and the times that the goods they contain are due in the plant are given in the following table. Truck Unloading Time (minutes) Time Material Is Due 1 20 1:25 P.M. 2 14 1:45 P.M. 35 1:50 P.M. 4 10 1:30 P.M. Determine the schedules that result for each of the rules FCFS, SPT, EDD, and CR. In each case compute the mean flow time, average tardiness, and number of tardy jobs.

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter12: Queueing Models

Section12.5: Analytic Steady-state Queueing Models

Problem 18P

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Four trucks, 1, 2, 3, and 4, are waiting on a loading dock at XYZ Company that hasonly a single service bay. The trucks are labeled in the order that they arrived at thedock. Assume the current time is 1:00 P.M. The times required to unload each truck and the times that the goods they contain are due in the plant are given in thefollowing table.Truck Unloading Time (minutes) Time Material Is Due1 20 1:25 P.M.2 14 1:45 P.M.3 35 1:50 P.M.4 10 1:30 P.M.Determine the schedules that result for each of the rules FCFS, SPT, EDD, andCR. In each case compute the mean flow time, average tardiness, and number oftardy jobs.
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