Project Management. Dr Jae K. Shim
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their completion dates, or only partially met their requirements because there was no viable baseline plan before the project was started.
The baseline plan for a project can be displayed in graphical or tabular format for each time period (i.e. week, month) from the start of the project to its completion. (Plans are discussed and illustrated in Chapter 3.) Information should include:
►The start and completion dates for each activity
►The amounts of the various resources that will be needed during each time period
►The budget for each time period, as well as the cumulative budget from the start of the project through each time period
Once a baseline plan has been established, it must be implemented. This involves performing the work according to the plan and controlling the work so that the project scope is achieved within the budget and schedule, to the customer’s satisfaction.
Once the project starts, it is necessary to monitor progress to ensure that everything is going according to plan. At this stage, the project management process involves measuring actual progress and comparing it to planned progress. To measure actual progress, it is important to keep track of which activities have actually been started and/or completed, when they were started and/or completed, and how much money has been spent or committed. If at any time during the project comparison of actual progress to planned progress reveals that the project is behind schedule, overrunning the budget, or not meeting the technical specifications, corrective action must be taken to get the project back on track.
Before a decision is made to implement corrective action, it may be necessary to evaluate several alternative actions to make sure the corrective action will bring the project back within the scope, time, and budget constraints of the objective. Be aware, for instance, that adding resources to make up time and get back on schedule may result in overrunning the planned budget. If a project gets too far out of control, it may be difficult to achieve the project objective without sacrificing the scope, budget, schedule, quality, or all of the above.
The key to effective project control is measuring actual progress and comparing it to planned progress on a timely and regular basis and taking corrective action immediately, if necessary. Hoping that a problem will go away without corrective intervention is naïve and irresponsible. Based on actual progress, it is possible to forecast a schedule and budget for completion of the project. If these parameters are beyond the limits of the project objective, corrective actions need to be implemented at once.
Attempting to perform a project without first establishing a baseline plan is foolhardy. It is like starting a vacation without a roadmap, itinerary, and budget. You may land up in the middle of nowhere— out of money and out of time.
Benefits of Project Management
The ultimate benefit of implementing project management techniques is having a satisfied stakeholder (customer)—whether you are the customer of your own project, such as remodeling your basement, or a business (contractor) being paid by a customer to perform a project. Ultimately, in the close-out phase, the customer has the greatest influence on the quality, scope, time and cost of the project. Completing the full project scope in a quality manner, on time, and within budget provides a great feeling of satisfaction. For a contractor, it could lead to additional business from the same customer in the future or to business from new customers referred by previously satisfied customers.
CHAPTER 4Using the Work Breakdown Structure to Plan a Project
Planning answers the questions “What must be done?,” “How long will it take?,” and “How much will it cost?” Planning the “What” is vital; projects frequently fail because a significant part of the work is forgotten. In addition, once tasks have been identified, the time and resource requirements must be determined. This is called estimating.
A major problem in project planning is determining how long tasks will take and what it will cost to do them. Inaccurate estimates are a leading cause of project failures, and missed cost targets are a common cause of stress and recrimination in project management.
The most useful tool for accomplishing all of these tasks is the Work Breakdown Structure (WBS). The idea behind the WBS is simple: you can subdivide a complicated task into smaller tasks, until you reach a level that cannot be further subdivided. Decomposition is used in developing the WBS. A that point, it is usually easier to estimate how long the small task will take and how much it will cost to perform than it would have been to estimate these factors at higher levels.
Nevertheless, it is still no easy feat to estimate task durations for activities that have never been performed before. Because this is the typical situation in engineering hardware and software development projects, we might expect many of these estimates to be in error, and this seems to be demonstrated by experience. Still, the Work Breakdown Structure makes it easier to estimate knowledge tasks than any other tool we have.
A Simple Example
As an example, if I want to clean a room (see Exhibit 7), I might begin by picking up clothes, toys, and other things that have been dropped on the floor. I could use a vacuum cleaner to get dirt out of the carpet. I might wash the windows and wipe down the walls, then dust the furniture. All of these activities are subtasks performed to clean the room.
As for vacuuming the room, you might have to get the vacuum cleaner out of the closet, connect the hose, plug it in, push the vacuum cleaner around the room, empty the bag, and put the machine back in the closet. These are still smaller tasks to be performed in accomplishing the subtask called vacuuming. The diagram in Exhibit 7 shows how this might be portrayed in WBS format.
Exhibit 7: WBS Diagram to Clean a Room
Note that we do not worry about the sequence in which work is performed when we do a WBS. That will be worked out when we develop a schedule. However, you will probably find yourself thinking sequentially, as it seems to be human nature to do so. The main idea of doing a WBS is to capture all of the tasks. So if you mind yourself and other members of your team thinking sequentially, don’t be too concerned, but don’t get hung up on trying to diagram the sequence or you will slow down the process of task identification.
The typical WBS has three to six levels, and these can be labeled as shown in Exhibit 8. It is, of course, possible to have projects that require a lot more levels. Twenty levels is considered to be the upper limit, and that is a huge project. Note that level 1 is called the program level. The difference between a program and a project is just one of degree.
Exhibit 8: WBS Level Names
An example of a program is the development of an airplane. For example, the WBS for Boeing’s 787 airplane program might have been drawn as shown in Exhibit 9. Notice that the engine, wing, and avionics are large enough jobs to be called projects in their own right. In fact, the program manager’s job is to make sure that the projects are all properly integrated. The engine mounts on the wing, so, somewhere in the structure to develop the engine, there will be an activity called “Design wing mounts.” And for the wing, there will be an activity called “Design engine mounts.” If these are not coordinated properly, you will wind up with an engine that won’t mount on the wing. The job of coordinating these is called system integration.