Question

ISE 361 2019 Spring Homework Southwestern University Southwestern University (SWU), a large state college in Stephenwille, Texas, 30 miles southwest of the Dallas/Fort Worth metroplex, enrolls close to 20,000 students. In a typical town-gown relationship, the school is a dominant force in the smalil city, with more students during fall and spring than permanent residents. A longtime football powerhouse, SWU is a member of the Big Eleven conference and is usually in the top 20 in college footbal rankings. To boster its chances of reaching the elusive and long-desired number-one ranking, in 2009, swu hired the legendary Phil Flamm as its head coach One of Flamm's demands on joining SWU had been a new stadium. With attendance increasing. Swu administrators began to face the issue head-on After 6 months of study, much political arm wresting, and some serious financial analysis, Dr. Joel Wisner, president of Southwestern University, had reached a decision to expand the capacity at its on-campus stadium. Adding thousands of seats, including dozens of luxury skyboxes, would not please everyone. The influential Flamm had argued the need for a first-class stadium, one with built-in dormitory rooms for his players and a palatial office appropriate for the coach of a future NCAA champion team. But the decision was made, and everyone, including the coach, would learn to live with it The job now was to get construction going immediately after the 2015 season ended. This would allow exactly 270 days until the 2016 season opening game. The contractor, Hill Construction (Bob Hill being an alumnus, of course), signed his contract. Bob Hill looked at the tasks his engineers had outlined and looked President Wisner in the eye. "I guarantee the team will be able to take the field on schedule next year," he said with a sense of confidence. "I sure hope so," replied Wisner. "The contract penaltyof $10,000 per day for running late is nothing compared to what Coach Flamm will do to you if our opening game with Penn State is delayed or canceled. Hill, sweating slightly, did not need to respond. in football-crazy Texas, Hill Construction would be mud if the 270-day target was missed Back in his office, Hill again reviewed the data (see Table 3.6 ) and noted that optimistic time estimates can be used as crash times. He then gathered his foremen, "Folks, if we're not 75% sure well finish this stadium in less than 270 days, I want this project crashed! Give me the cost figures for a target date of 250 days-also for 240 days. I want to be eorly, not just on timel Discussion Questions 1. Develop a network drawing for Hill Construction and determine the critical path. How long is the project expected to take? 2. What is the probability of finishing in 270 days? 3. If it is necessary to crash to 250 or 240 days, how would Hill do so, and at what costs? As noted in the case, assume that optimistic time estimates can be used as crash times TME ESTIMATES (DAYS CRASH COST/DAY $1,500 PREDECESSORIS) OPTIMISTIC MOST LIKELY PESSIMISTIC ACTIVITY | DESCRIPTION A Bonding, insurance, tax structuring 8 Foundation, concrete footings for bones C Upgrading *bor stadium seating D Upgrading walkways, stairwels, elevators E interior wiring. lathes F inspection approvals 100 100 1,900 0.1 0.1 D, F Plumbing H Panting 0.1 0.1 0.1 Kinspection 4 500 L Final detail workucleanup

Answer 1

Answer 1:-

Activity	Optimistic (a)	Most Likely (m)	Pessimistic (b)	Expected Time	Variance
A	20	30	40	30	11.11
B	20	65	80	60	100.00
C	50	60	100	65	69.44
D	30	50	100	55	136.11
E	25	30	35	30	2.78
F	0.1	0.1	0.1	0.1	0.00
G	25	30	35	30	2.78
H	10	20	30	20	11.11
I	20	25	60	30	44.44
J	8	10	12	10	0.44
K	0.1	0.1	0.1	0.1	0.00
L	20	25	60	30	44.44

90E 120 30 120 F 140 260 0.1 260 120.1 120 30150 230 L 260 30 B 30 60 60 120 90 180 H 200 0 230 30260 200 0 230 180 20 200 0 150 G 180 200 30 230 0 150 30 180 0A 30 0 030 30 95 30 C 0 210 K 19.9 230 0.1230 30 6595 200J 19.9 220 10 230 210 210.1 95 D 150 0 95 55150 ES ID ER SL LS DR LF ES Early Start EF- Early Finish LS-Late Start LF Late Finish DR Duration SL Slack

expected time ACDGHIL (on critical path) = A + C + D + G + H + I + L

= 260 days

Answer :- Project Variance = (total variances of activities on critical path) = 11.11 + 69.44 + 136.11 + 2.78 + 11.11 + 44.44 + 44.44= 319.43 days

Project Standard Deviation = SQRT (319.43) = 17.87 days

Z = = (270 – 260) / 17.87= 0.56

As per Normal Table in Appendix 1, for Z value of 0.56, the probability of 0.71226. There is a 71.23% chance that the project will finish on 270 days.

Answer:-

We select the activity on the critical path with the smallest crash cost/day which is activity A. Thus, we can reduce the total project completion date by 10 days to finish the project in 250 days.

Reduced cost for 10 Days for activity A would be $ 1500 * 10 = $ 15000

To finish the project in 240 days, another 10 days need to be crashed. This reduction can be achieved by least cost along the critical path by reducing activity H by 10 days for an additional cost of $20,000. This solution is summarized in the following table:

Activity	Days	Reduced Cost ($)
A	10	15000
H	10	20000
Total	20	35000