Concept explainers
(a)
Interpretation:
The best sequence in terms of the average flow time:
Concept Introduction:
(a)
Explanation of Solution
Given information:
The table below contains the information about five jobs waiting to be processed at stamping machine
Job | Processing Time (hrs) | Due (hrs) |
Schedule the jobs based on the earliest due date
Hours | |||||||||||||||
Job |
Thus, calculate the average flow time that is required to finish the each job:
Now, calculating the average tardiness, it is given that job
The job
The job
The job
The job
Adding the delay time of the order and divide it by the number of the orders;
From the table, it is observed that job
Calculate the critical ratio by dividing the hours until due by the processing time for the each job.
Job | Processing Time (hrs) | Due (hrs) | Critical ratio |
Now, schedule the based on the ascending order of the critical ratios.
Hours | |||||||||||||||
Job |
Calculate the average flow time by adding the delay time of the order and divide it by the number of the orders;
Calculate the tardiness for the each job,
that job
The job
The job
The job
The job
Adding the tardiness of the order and divide it by the number of the orders;
From the table, it is observed that the job
Schedule the jobs based on the
Hours | |||||||||||||||
Job |
Thus, calculate the average flow time that is required to finish the each job:
Now, calculating the average tardiness, it is given that job
The job
The job
The job
Now, calculate the average tardiness,
Thus, the job
From the above calculation, the average flow time based on methods:
Therefore, shortest processing time gives the lowest average flow time.
(b)
Interpretation:
The best sequence in terms of the average tardiness:
Concept Introduction:
Schedule the job on the basis of the
Schedule the job on the basis of the
(b)
Explanation of Solution
Given information:
The table below contains the information about five jobs waiting to be processed at stamping machine
Job | Processing Time (hrs) | Due (hrs) |
From the above calculation, the average tardiness based on the different methods,
Therefore, shortest processing time gives the lowest average tardiness.
(c)
Interpretation:
The finish time of job
Concept Introduction:
Schedule the job on the basis of the
Schedule the job on the basis of the
(c)
Explanation of Solution
Given information:
The table below contains the information about five jobs waiting to be processed at stamping machine
Job | Processing Time (hrs) | Due (hrs) |
From the above calculations, the completion of the job
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Chapter 14 Solutions
Practical Operations Management
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- Consider the following process at a pharmacy. Customers drop off their prescriptions either in the drive-through counter or in the front counter of the pharmacy. Customers can request that their prescription be filled immediately. In this case, they must wait between 15 minutes and one hour depending on the current workload. Most customers are not willing to wait that long, so they opt to nominate a pick-up time at a later point during the day. Generally, customers drop their prescriptions in the morning before going to work (or at lunchtime) and they come back to pick up the drugs after work, typically between 5pm and 6pm. When dropping their prescription, a technician asks the customer for the pick-up time and puts the prescription in a box labelled with the hour preceding the pick-up time. For example, if the customer asks to have the prescription be ready at 5pm, the technician will drop it in the box with the label 4pm (there is one box for each hour of the day). Every hour, one…arrow_forwardAn insurance claims work area has five claims waiting for processing as follows: Job Processing Time Due Date (Di ) 1 18 31 2 14 25 3 12 23 4 19 24 5 10 37 Use the Excel Sequencing template to find the average flowtime, average and maximum tardiness, and average lateness for the following sequences: SPT sequence, EDD sequence, and the sequence 4-3-2-1-5. Round your answers for the average values to two decimal places. The SPT sequence is - - - - . Average Flow Time Average Tardiness Maximum Tardiness Average Lateness The EDD sequence is - - - - . Average Flow Time Average Tardiness Maximum Tardiness Average Lateness 4-3-2-1-5 sequence: Average Flow Time Average Tardiness Maximum Tardiness Average Lateness What sequencing rule do you recommend? The ___________ is recommended as it minimizes average flow time and number of jobs in system.arrow_forwardCourtney is a programmer receiving requests each week to analyze a large data base. Five jobs were on her desk Monday morning, and she must decide in what order to write the code Assume that all jobs arrived today (day 1 and hour 1), in the order shown below. Courtney has assigned the number of hours required to do the coding as noted. Note that Courtney works an 8-hour day and today is a work day. DURATION (HOURS JOB k A BUD C E DUE DATE (HOURS HENCE) 10 16 14 36 26 REQUIRED) 6 3 7 15 8 a) Sequence the jobs according to EDD. According to the EDD rule, the sequence of jobs should be A, C, B, E, D b) What is the average completion (flow) time? The average completion (flow) time is days (round your response to one decimal place).arrow_forward
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