Question

# The following jobs are waiting to be processed at Rick? Solano's machine center.? Solano's machine center...

The following jobs are waiting to be processed at Rick? Solano's machine center.? Solano's machine center has a relatively long backlog and sets a fresh schedule every 2? weeks, which does not disturb earlier schedules. Below are the jobs to be scheduled? today, which is day 241 ?(day 241 is a work? day). Job names refer to names of clients and contract numbers. Compute all times based on initiating work on day 241.

(Job) (Date Job Received) (Due Date Duration (days))

BR-02 225 270 25

CX-01 230 320 35

DE-06 235 360 40

RG-05 231 310 30

SY-11 228 300 15

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):

The average tardiness? (job lateness) for the sequence developed using the EDD rule? =

The percentage utilization for the sequence developed using the EDD rule? =

The average completion time for the sequence developed using the EDD rule? =

The average number of jobs in the system for the sequence developed using the EDD rule? =

The Earliest Due Date rule is used to minimize the maximum lateness of schedule. According to EDD rule, the jobs are sequenced from earliest to latest due date of job. The sequence of EDD is as follows:

 1 2 3 4 5 6 = 5+4 7 8 = 7 - (240 day) 9 = Maximum (0, (6 – 8)) Sequence Job Date Received Processing time Work Begins Flow Time Job Due date Starting from day 241 Job Lateness (Tardiness) pi di 1 BR-02 225 25 0 0+25 = 25 270 270-240 = 30 =max(0, (25-30)) = max(0, -5) = 0 2 SY-11 228 15 25 40 300 60 0 3 RG-05 231 30 40 70 310 70 0 4 CX-01 230 35 70 105 320 80 25 5 DE-06 235 40 105 145 360 120 25 145 385 50

Total Processing time = 145 days

Total flow time for 5 jobs = 385 days

Total tardiness = 50 days

Average tardiness = total tardiness/number of jobs in sequence = 50/5 = 10 days

Percentage Utilization = total processing time/total flow time x 100

Percentage Utilization = 145/385 x 100 = 37.66%

Average completion time = Total Flow time/number of jobs in sequence = 385/5 = 77 days

Average number of jobs in system = Sum of total flow time/Total processing time = 385/145 = 2.65

For EDD:

Average tardiness = 10 days

Percentage Utilization = 37.66%

Average completion time = 77 days

Average number of jobs in system = 2.65 jobs