International Development homework help

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Unit 8 ProblemsNameInstitutional AffiliationUnit 8 ProblemsProblem 6A. Sequence the jobs using (1) FCFS, (2) SPT, (3) EDD, and (4) CR. Assume the list is by order of arrival.First      Come, First Served (FCFS)SequenceJob   TimeFlow   TimeDue   DateLatenessA1414200B1024168C7311516D6371720TOTALS3710644The sequencing of the jobs based on the First Come, First Served (FCFS) basis is A – B – C – D, and the chart shows that shows that jobs B, C, and D will be late by a total of 44 days. Shortest      Possible Time (SPT)SequenceJob   TimeFlow   Time Due   DateLateness   D66170C713150B1023167A14372017TOTALS377924The sequencing on the jobs based on the Shortest Possible Time is D – C – B – A, and the chart shows that jobs B and A will be late by a total of 24 days. Earliest      Due Date (EDD)SequenceJob   TimeFlow   TimeDue   DateDays   TardyC77150B1017161D623176A14372017TOTALS378424The sequencing of the jobs based on the Earliest Due Date (EDD) is given as C – B – D – A, and the average completion time is 42 days. Critical      RatioSequenceJob   TimeFlow   TimeDue   DateTardinessA14372017C7441529D6501733B10601644TOTALS37191123All the critical ratios are greater than 1, and this indicates that all the jobs will be completed in time if scheduled as A – C – D – B. B. For each of the methods in part a, determine (1) the average job flow time, (2) the average tardiness, and (3) the average number of jobs at the work center. Average      time flow a) FCFS = average completion time/number of jobs = 106/4 = 26.5 days. b) SPT = average completion time/number of jobs = 79/4 = 19.75 daysc) EDD = average completion time/number of jobs = 84/4 = 21 days d) CR = average completion time/number of jobs = 191/4 = 47.75 days Average      tardiness a) FCFS = 44/4 = 11 daysb) SPT = 24/4 = 6 days c) EDD =24/4 = 6 days d) CR = 123/4 = 30.75 days Average      number of jobs a) FCFS = 106/37 = 2.865b) SPT = 79/37 = 2.135c) EDD = 84/37 = 2.270d) CR = 191/37 = 5.162C. Is one method superior to the others? Explain. None of the methods is superior than the others because they each have their inherent weaknesses in addition to their strengths. For example, using the FCFS and SPT priority rules results in the increased delays in jobs that require longer times to complete while the EDD approach tends to ignore the processing times during the scheduling. However, the CR method has the most weaknesses in scheduling of the jobs. Problem 11Given the operation times provided: a. Develop a job sequence that minimizes idle time at the two work centers. The determination of the job sequence that would reduce the idle time at the two work centers is completed using the Johnson’s as shown in the table below: Developing   the Job SequenceIterationJob   SequenceComments ADThe   shortest job time is 12 minutes for D at Center 2, and thus D is scheduled   last. BBDD   is then removed from the table of eliminated times and the next least job   time is observed as 16 minutes for B at Center 1. Thus, B is scheduled first.   CBADB   is then eliminated from the table and the next least job time is 20 minutes   for A at Center 1 and is there scheduled next. DBAFDA   is then eliminated from the table and the next least time is 24 minutes for F   at Center 2 and this is scheduled next. EBAEFDF   is then eliminated from the table and the next least time is E at Center 2   and this is scheduled next. FBACEFDE   is then eliminated from the table and the last least time is 43 minutes at   Center 1 and it is scheduled the earliest. Thus the job sequence that reduces the idle time at Centers 1 and 2 is given as B – A – C- E – F – Db. Construct a chart of the activities at the two centers, and determine each one’s idle time, assuming no other activities are involved. The chart of activities for the two centers is shown below: 01603679114156216BACEFDBACEFD16467379130158218216228From the chart, the idle time at Center is given as 0 minutes while the total idle time at Center 2 is given as ((16 – 0) + (79 – 73) + (216 – 182)) = 16 + 6 + 34 = 56 minutes.