2. Oakland seaport handles thousands of containers every day. Containerships arrive at the Oakland port once every 4 hours, on an average. Unloading of a ship takes 6 hours on an average. Assume multiple M|M|1 system. You are hired as a consultant to analyze this seaport operation and determine the following: a. Minimum number of ship-unloading facilities. b. Probability (each unloading facility is busy) c. Probability (each unloading facility is idle) d. Average number of ships in the system, that is, number of ships in the line including the one being unloaded. e. Average number of ships waiting to be unloaded, that is, number of ships in the line excluding the one being unloaded. f. Average time a ship spends in the system, that is, waiting time plus unloading time. g. Average time a customer spends in the waiting line before reaching the unloading berth. h. After calculating (d) to (g), you realized that too many ships are in the line for service and there have been complaints recently. In view of your knowledge of queuing analysis, you would advise as a consultant to install two more unloading facilities so that the arrival rate is shared by four unloading facilities. Now having 4 unloading facilities installed, determine again (b) to (g) above.

2. Oakland seaport handles thousands of containers every day. Containerships arrive at the Oakland port once every 4 hours, on an average. Unloading of a ship takes 6 hours on an average. Assume multiple M|M|1 system. You are hired as a consultant to analyze this seaport operation and determine the following: a. Minimum number of ship-unloading facilities. b. Probability (each unloading facility is busy) c. Probability (each unloading facility is idle) d. Average number of ships in the system, that is, number of ships in the line including the one being unloaded. e. Average number of ships waiting to be unloaded, that is, number of ships in the line excluding the one being unloaded. f. Average time a ship spends in the system, that is, waiting time plus unloading time. g. Average time a customer spends in the waiting line before reaching the unloading berth. h. After calculating (d) to (g), you realized that too many ships are in the line for service and there have been complaints recently. In view of your knowledge of queuing analysis, you would advise as a consultant to install two more unloading facilities so that the arrival rate is shared by four unloading facilities. Now having 4 unloading facilities installed, determine again (b) to (g) above.

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter5: Network Models

Section5.5: Shortest Path Models

Problem 32P

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