9.2 Distinguish between serial activities and concurrent activities. Why do we seek to use concurrent activities as a way to shorten a project's length?

9.3 List three methods for deriving duration estimates for project activities. What are the strengths and weaknesses associated with each method?

9.5 "The shortest total length of a project is determined by the longest path through the network." Explain the concept behind this statement. Why does the longest path determine the shortest project length?

9.7 Consider a project such as moving to a new neighborhood, completing a long-term school assignment, or even cleaning your bedroom. Develop a set of activities necessary to accomplish that project, and then order them in a precedence manner. Explain and defend the number of steps you identified and the order in which you placed those steps for best completion of the project.

9.8 What is the time estimate of an activity in which the optimistic estimate is 4 days, pessimistic is 12 days, and most likely is 5 days? Show your work.

9.9 What is the time estimate of an activity in which the optimistic time is 5 days, the likely time is 8 days, and the pessimistic time is 14 days? Show your work.

CASE STUDY 9.1 Moving the Historic Capen House11

Once occupied by one of Winter Park, Florida's earliest residents, James Seymour Capen, the majestic Capen House, originally built in 1885, was set to be demolished so buyers could build on its land. Luckily, its new owners decided to give preservationists, who were eager to see the home saved, time to plan and raise funds to move the historic house across Lake Osceola. To save the 200-ton historic house, the group of preservationists moved it across the lake in two separate pieces, to where it could rest next to the Albin Polasek Museum.

To accomplish this construction feat, contractor Frank Roark acted almost as a conductor of a symphony composed of moving, interdependent parts. Each part of this seemingly impossible project had to be broken down into small, achievable tasks and sequenced in a way that made logical sense. During a 2013 radio interview with Mr. Roark, the project's chief contractor described the intricacies of the complex project by stating that there were "complicating, challenging factors that add to the excitement and fun of the whole thing."

During the interview, Mr. Roark described the scope of the project work in great detail. He started by explaining how the team would assemble a barge large enough to transport the house. Additionally, he discussed the preparation of the historic Capen House along with its original fixtures:

"Well, what we do is we have to assemble the barge, the barge is big, it's going to have to be 40 feet by 60 feet and so you can't just come up with a 40 foot by 60 foot barge, truck it into town, and roll it to the dock. So the way it's done is the barge is comprised of individual smaller barges that are typically 10 feet wide and 20 or 40 feet long. Those are brought in on flatbed trucks brought down onto the property, dragged down onto the lake into the water, and then another piece and another piece. Those pieces are pinned together to form a large raft. And you can keep adding those individual pieces until you get a large barge as long as you need to carry the weight of a house. The way that the house is calculated and by knowing what it's made out of and the sizes, and so, the barge is assembled and then a couple of small motor boats, one in the front and one in the back, pull and push it slowly across the lake over to where the house is currently located. It comes up to the shore and then a ramp is built from the barge up onto the shore, obviously a strong ramp. Then the house has to be cut into two pieces because the lot is very narrow down by the lake and the constraints of some existing trees and another building makes it such that the house would not fit between them in one piece. So we have to cut the house in half into two pieces, and we will move each piece one at a time up on wheeled dollies, roll it down to the lake, roll it over the ramp, onto the barge, and then the barge will be motored across the lake where each half will be brought to its eventual resting place. That process is repeated for the second half."

The interviewer continued to ask Mr. Roark about the work required to prepare the other side of the lake where the Capen House would reside once it had been moved. Mr. Roark described a ramp that had to be assembled on that side of the lake as well:

"The ramp has to be assembled again on the other side to allow the house to roll off because the barge, although it only drops about 3-3.5 feet of water, it can't just literally go right onto the shore. It can stop pretty close, but there's going to be some gap there that has to be bridged with the ramp, the ramp has to be wide enough and strong enough that a hundred tons for half of the house can roll over and head up, go on up the property.

Finally, Mr. Roark described the delivery of the house to its final resting place:

"It's done with some heavy equipment that is, would be, in front of the house, and these would be tow trucks and they have winches on them, and steel cables are taken down to the house and imagine if you would like a wagon where you would hold the handle and you would pull the wagon. Well, the house will have a couple of connecting points and the steel cables will go to that the steel beams of the house are actually sitting on. And they will go back up to these tow vehicles, which are anchored in place by some heavy front-end loaders so that those don't slip down towards the house. And so those things start winching the house forward and the house up on wheeled dollies so it starts rolling slowly but it does, it rolls forward. So it's slowly pulled or winched forward and then as it gets closer to the winches, those are then moved further up the hill and the process is repeated where it is winched along a little bit at a time until it gets to the final destination.

Last, but not least, Mr. Roark shared the fact that there were also two obstacles on the lake front of the resting place for the Capen House that had to be handled with considerable care:

"And, there's also a large dock and boat house down on the lake exactly where the barge has to go and where the house has to roll through it. So we have to take the boat house and the dock and put them on it, their own little barge, cut them loose, float them off to the side out of the way, so that we can make way for the large barge and the ramp and the house to roll onto it. And once those house pieces are moved and out of the way we have to float the boat house and the dock and put it right back in the original position."

There is certainly no doubt that it took a well-orchestrated team of dedicated individuals to make this move happen. Once the house was delivered across the lake and reassembled, it was restored into the beautiful historic venue it is today. This construction feat resulted in an admirable transformation: a charming public event space for the Winter Park community to appreciate for many years to come.12

Questions Based on the work described by Frank Roark in his radio interview, construct a list of project work activities with IDs, descriptions, and predecessor tasks.

Construct an AON network diagram for the activities required to complete the Capen House move. Be sure to visualize the interdependencies of the work tasks and to follow network diagramming conventions.

Identify concurrent, merge, and burst activities and explain the impact of convergences upon the project planning process.

If you were the project manager for moving the Capen House, what are some of the scheduling challenges you might anticipate with this project based upon your network diagram? How would you ensure project success?