A The following jobs are waiting to be processed at the same machine center. Jobs are logged as they arrive: B. 3. Job Due Date Duration (days) 314 4. D. 315 3 C 313 D 312 16 E 325 40 The average tardiness (job lateness) for the sequence developed using the FCFS rule = 4.20 days (round your reaponse to two decimal places) All dates are specified as manufacturing planning calendar days. Assume that all jobs armve on day 275. Assume each job starts at the beginning of the day and finishes at the end of the day (a job that begins on day 275 and takes 8 days will finish on day 282, and the next job begins in the moming of day 283) Compute all times based on initiating work on day 275. The percentage utilization for the sequence developed using the FCFS rule = 54.14 % (enter your response as a percentage rounded to two decimal places). b) Using the EDD (earliest due date) decision rule for sequencing the jobs, the order is (to resolve a tie, use the order in which the jobs were received): Sequence Job D 3 A 4. B

A The following jobs are waiting to be processed at the same machine center. Jobs are logged as they arrive: B. 3. Job Due Date Duration (days) 314 4. D. 315 3 C 313 D 312 16 E 325 40 The average tardiness (job lateness) for the sequence developed using the FCFS rule = 4.20 days (round your reaponse to two decimal places) All dates are specified as manufacturing planning calendar days. Assume that all jobs armve on day 275. Assume each job starts at the beginning of the day and finishes at the end of the day (a job that begins on day 275 and takes 8 days will finish on day 282, and the next job begins in the moming of day 283) Compute all times based on initiating work on day 275. The percentage utilization for the sequence developed using the FCFS rule = 54.14 % (enter your response as a percentage rounded to two decimal places). b) Using the EDD (earliest due date) decision rule for sequencing the jobs, the order is (to resolve a tie, use the order in which the jobs were received): Sequence Job D 3 A 4. B

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 21P

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The Earliest Due date (EDD) rule for sequencing a given set of jobs usually ____________ Select one: a. minimizes the maximum lateness and tardiness. b. minimizes average flow time and work in process inventory. c. maximizes the average lateness and tardiness. d. minimizes the average lateness and tardiness. e. maximizes the minimum lateness and tardiness.
The first five columns of the following table contain information about a set of four jobs that just arrived (end of Hour 0 or beginning of Hour 1) at an engine lathe. They are the only ones now waiting to be processed. Several operations, including the one at the engine lathe, remain to be done on each job. Determine the schedule by using (a) the CR rule and (b) the S/RO rule. Compare these schedules to those generated by FCFS, SPT, and EDD. Job ProcessingTime at EngineLathe (hours) TimeRemainingUntil Due Date(days) Number ofOperationsRemaining Shop TimeRemaining(days) CR S/RO 1 2 3 4 2.3 10.5 6.2 15.6 15 10 20 8 10 2 12 5 6.1 7.8 14.5 10.2 2.46 1.28 1.38 0.78 0.89 1.10 0.46 -0.44
24 The job that arrived first at a work center or machine will be processed first and completed. Which of the following priority rules does this statement represent? a first come, first served b shortest processing time c critical ratio d earliest due date
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