Pages Menu
Categories Menu

Posted by on Dec 3, 2012

Scheduling: Planning to Get Work Done – Part II

gantt_chart-300x200WORK In part two of this scheduling blog, I want to concentrate on the “Develop Schedule” process and how the intersection of work and resources applies to schedule compression. As I stated previously, scheduling is linear and predictable, but the instance we add humans we may get non-linear behavior. Types of Work Work type is a predictor of how the duration is affected by people assignments. I believe there are three work types: Moving Bricks, Meeting, and Truck Driving. Moving Bricks type work is illustrated by my having a pile of bricks to move and it will take me all day to move the bricks. If you help me and you are an equally talented brick mover then it will take both of us half a day to move the bricks. Therefore, adding resources reduces the duration of brick moving type work. Meeting type work is like having a meeting or training a course. If the course is three days long whether there are 2 people or 20 people in the classroom, the course takes three days. Therefore, adding resources does not reduce the duration of meeting type work. Truck driving type work has a fixed duration and effort. For instance, if I need to drive a truck from Denver, CO to Kansas City, MO, Google Maps says it is 600 miles and takes about 10 hours. The effort (10 hours worth of driving) and the duration (10 hours worth of clock-time) are the same for me. Now let’s assume that you join me in the truck. Effort and duration remain the same, 10 hours, but I only have to drive 5 hours and you only have to drive 5 hours for us to make it to Kansas City with the same result as if I had traveled alone. Therefore, adding resources reduces the individual contribution of the resources for truck driving type work. Two people 50%-50%, three people 33%-33%-33%, four people 25%, five people won’t fit in the truck. Critical Path The critical path is that collection of tasks in the network diagram which represent the longest duration from start to finish. Another way to state it is any task which if delayed will delay the end date is a critical path task. Another way to say it is any task with a calculated float of zero is a critical path task. So the magic of critical path is that we can directly affect the project end date by manipulating critical path tasks if we know which ones they are. Scheduled Compression Schedule compression is the technique of shortening the project schedule duration (read end date) without reducing the project scope (same amount of work). The PMBOK® Guide tells us that we can employ three techniques to compress the schedule: crashing, fast tracking, and scope management. Typical approaches for crashing a schedule include reducing task durations and increasing the assignment of resources to the task. I call this throwing more resources at the problem. I either need more people or more of people (availability) to affect the task duration. Fast tracking is defined as changing the network logic to overlap phases that would normally be done in sequence or to perform scheduled activities in parallel. I call this changing the order of the work. If we can find tasks which are currently in series that can be worked in parallel, we can reduce the overall duration of the project, maybe. Scope management is that practice which looks for tasks that can be removed or reduced in duration to effect the end date. We can either not do something or do less of something like testing. Not doing something will remove the work from the project, doing less of something may reduce the duration, but will almost always increase risk. Interdependency So far, we’ve talked about resources (in Part I), work types, critical path, and schedule compression as individual events. Now let’s bring it all together and see how schedule compression really works. The end date needs to be adjusted to shorten the schedule, so we can crash by getting more resources! But, they must be applied to critical path tasks and work types which will lend themselves to getting the work done faster. So, we must apply more persons or more of persons (overtime as an example) to Moving Bricks tasks which are on critical path. If we apply persons to Meeting type tasks or Truck Driving type tasks on critical path, nothing happens to the end date and you probably frustrated the humans. Please don’t forget the non-linear possibility of adding resources. Do the resources get along? Do they work well together? Are they equal to the task and each other? It is not certain that two people will get the work done in half the time, but we should shorten the critical path just the same. So let’s fast track the schedule. It makes perfectly good sense that moving tasks from serial to parallel work will get the work done faster, but only on critical path tasks! And we haven’t begun to discuss the reality of hard logic versus discretionary logic inherent in the network. Only discretionary logic tasks are available for movement to parallel operation and only on critical path. What about those resources? If Fred is a resource on both serial critical path tasks that you have now placed in parallel, then Fred is possibly over allocated and you still aren’t going to get the work done faster. How about scope management? Again, only critical path tasks need apply. This is the most difficult approach, in my opinion. You built the schedule from the WBS which identified all the work required to accomplish the scope of the project. Now we are saying that we can take work out. Not without change management approval and not if it reduces the effectiveness of the solution. Increasing risk is the reality of scope management and there needs to be a hardy discussion with the sponsor before selecting this option. Scheduling is a wonderful tool to help you see what needs to be done by whom, when. I suggest that you analyze the schedule and the resource loading critically. There are rules to apply and contraindications to consider in creating the very best schedule.

Why should you buy already written essays from our writing services? What has made a lot of students to buy already written essays from our writing services is the type of essay writing help that we provide them. We not only provide papers which will enable you get high class degree without any knowledge but we actually ensure that our already written essays have provided you with basic skills of essay writing.

Post a Reply

Your email address will not be published. Required fields are marked *