Schedling problems wih Heuristics.pdf

Ques.1. Andy Arthurson is an independent computer software consultant. After completing his

most recent project, he had five jobs awaiting completion. Following are the estimated work

times required to complete each job and the due dates requested by customers

Job Processing time (Days) Due Date(days from present)

A 12 52

B 16 37

C 8 28

D 20 57

E 6 31

Construct job sequence using the SPT,EDD, STR and CR rules and compute the average flow time,

average number of jobs in the system, average tardiness per job and number of jobs tardy for

each sequence.

Ques.2. Marine Electro-Plating has six customized electroplating jobs to process through its two-

stage production system. The estimated processing times for the jobs at each stage are given

below. Use Johnsons rule to construct a production sequence that minimizes the make span

time.

Job Stage 1 Stage 2

A 12 9

B 21 13

C 10 17

D 8 15

E 16 11

F 19 14

Ques.3. The track and field coach of Chesterfield High School must assemble a medley realy

team for a track meet. The relay race requires four runners to run legs of 200, 400, 800, and

1600 meters. The coach has five runners from whom to form the team and has estimated the

likely running times for each distance as follows:

Runner

Distance(m) 200 400 800 1600

Nancy 26 54 140 295

Sue 27 59 147 325

Jennifer 27 58 144 298

Alex 25 53 139 300

Beth 29 60 142 305 Times in Seconds

The coach must decide which four runners will be on the relay team and which race each will run.

Ques.4. Robert Crump is a student at Pomville University. Robert has five term papers due soon,

and he must decide in what order to complete them. Below are the estimated number of days

required to complete each paper and the due dates. Because all the instructors deduct 5 points

per day for any term paper that is tardy. Robert wants to minimize tardiness.

a. Use the SPT,EDD, CR, and STR rules to sequence the jobs. Which one(s) results in the least

average tardiness?

b. Which result(s) in the fewest tardy papers?

Course Estimated time(Days)

Due Date

History 3.5 7

Finance 3.0 8

P/OM 6.0 12

Accounting 4.5 17

Math 2.5 16

Ques.5. Suppose a company wanted to complete six jobs using a three-stage flow process with

the stage times given below. Construct the sequence in which the jobs should be run to minimize

the make span time.

Job Stage times(hr.) Stage 1 Stage 2 Stage 3

A 9 12 17

B 13 7 14

C 14 10 15

D 10 9 20

E 15 11 13

F 8 5 15