There are six jobs that are awaiting processing at a machining center. The jobs are shown in the table with their processing time and scheduled completion time
Schedule the jobs by earliest due date, shortest processing time and the critical ratio rule and calculate average lateness for all the jobs. Which scheduling technique performs BEST?
Job Process Time Due Time
A 12 25
B 8 32
C 15 40
D 10 15
E 20 27
F 17 46
What will be an ideal response?
Answer:
Shortest Processing Time
Job Process Time Due Time Completion Time Lateness
B 8 32 8 0
D 10 15 18 3
A 12 25 30 5
C 15 40 45 5
F 17 46 62 16
E 20 27 82 55
Average 14.0
Earliest Due Date
Job Process Time Due Time Completion Time Lateness
D 10 15 10 0
A 12 25 22 0
E 20 27 42 15
B 8 32 50 18
C 15 40 65 25
F 17 46 82 36
Average 15.67
Critical Ratio
Job Process Time Due Time Completion Time Lateness
E 20 27 20 0
D 10 15 30 15
A 12 25 42 17
C 15 40 57 17
F 17 46 74 28
B 8 32 82 50
Average 21.17
The sequence developed using the shortest processing time (SPT) rule has the lowest average lateness of 14.0. The earliest due date (EDD) sequence has an average lateness of 15.67 and the critical ratio sequence has an average lateness of 21.17. Based on this criterion, the SPT sequence is the best.
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The Atchison, Topeka &Santa Fe Railway (ATSFR) is currently all equity financed, but it is considering a leveraged capital structure. Selected financial information for ATSFR is provided in the table below
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Handheld PDAs pose a security risk in terms of both eavesdropping and spoofing
Indicate whether the statement is true or false.