Project Time Management
Project Time Management includes processes required to manage timely completion of the project. The work for performing the processes is preceded by a planning effort where the project team decides the scheduling methodology, a scheduling tool and establishes the format and criteria for developing and controlling the project schedule. Developing the project schedule uses the outputs from the processes of defining activities, sequencing activities, estimating activity resources and durations along with the scheduling tool to produce the schedule. This baseline is then used in the Control Schedule Process.
The list of Project Time Management processes includes:
The list of Project Time Management processes includes:
- Define Activities: Project work packages are decomposed into small components called activities. These activities represent the work necessary to complete the work package and provide a bases for estimating, scheduling, executing, monitoring and controlling project work.
Inputs:
Rolling Wave Planning: “Rolling Wave planning is a form of progressive elaboration planning where the work to be accomplished in the near term is planned in detail and the future work is planned at a higher level of the WBS." [3]
- Sequence Activities: Process of identifying and documenting logical relationships between different activities. Each activity has at least one predecessor and one successor except the first and last activity. To support a more realistic and achievable project schedule, it becomes necessary to use lead or lag time between various activities.
Tools and Techniques:
Precedence Diagramming Method (PDM): This method is used in Critical Path Method (CPM). It uses the concept of nodes representing the activities and arrows connecting these nodes showing the logical relationships.
Applying Leads and Lags: A lead allows an acceleration of the successor activity and a lag directs a delay in it. It is upon the project team to determine which dependencies may need a lead or a lag to accurately define the logical relationship.
- Estimate Activity Resources: Process of identifying and estimating the type and quantities of material, people, equipment or supplies required to perform each activity. For example, a construction project team will need to be familiar with local building codes. But if the local labor is not experienced with specialized construction techniques, then an additional cost for the consultant might be required. During this process, the project team identifies the resources it would need to complete the project.
Tools and Techniques:
Bottom-Up Estimating: This is used when an activity cannot be estimated with confidence. It is then broken down into more detail and the resource needs are estimated at that level. These estimates are then aggregated into a total quantity for each of the activity’s resources.
Outputs:
Resource Breakdown Structure: It is a hierarchical structure of the identified resources by resource category and resource type. Resource categories can include labor, material, equipment and supplies and resource types can include the skill level, grade level etc.
- Estimate Activity Durations: The process of estimating the number of work periods needed to complete individual activities with estimated resources. The duration estimate is progressively more accurate as the project progresses, since more detailed and precise data becomes available.
Tools and Techniques:
Analogous Estimating: It uses parameters such as duration, budget, size, weight and complexity from a previous similar project as the basis for estimating the same parameter or measure for a future project. This type of estimating is used when there is a limited amount of detailed information about the project. It is generally less accurate but can be reliable if the previous activities were actually similar in fact and not just in appearance and the project team members have the needed expertise.
Parametric Estimating: This technique uses a statistical relationship between historical data and other variables. For example, activity duration can be estimated on a design project by the number of drawings multiplied by the number of labor hours per drawing. Depending on the sophistication and underlying data built in the model, this type of estimating can give results with higher accuracy.
Three-Point Estimates: The accuracy of duration estimates can be improved by considering estimation uncertainty and risk. This concept of taking uncertainty and risk into consideration originated with PERT (Program Evaluation and Review Technique). It uses 3 estimates – Most Likely, Optimistic and Pessimistic. IT then calculates the expected activity duration using a weighted average formula.
Reserve Analysis: Duration Estimates might include contingency reserves, also known as time reserves or buffers to account for schedule uncertainty. The reserve may be a percentage of the estimated activity duration, fixed number of work periods. The reserve may be reduced, eliminated or used as necessary.
- Develop Schedule: It is the process of analyzing activity sequences, durations, resource requirements and schedule constraints to create the project schedule. It determines the planned start and finish dates for activities or milestones to create a baseline which can be used to track progress. But, this process is an iterative process as revising and maintain a realistic schedule continues as the project plan changes or the nature of the risk events evolves.
Tools and Techniques:
Critical Chain Method: It is a schedule network analysis technique that modifies the project schedule to account for limited resources. Basically, a resource constrained critical path is called a critical chain. The method also adds duration buffers that are non-work schedule activities to manage uncertainty.
Resource Leveling: It is a technique applied to a schedule that has already been analyzed by the critical path method. It can be used when shared or critical required resources are only available at certain times or in limited quantities. It can also be used to keep resource usage at a constant level; and can often cause the original critical path to change.
Schedule Compression: It shortens the project schedule without changing the project scope to meet schedule constraints or imposed dates. The techniques include crashing and fast tracking. Crashing determines how to obtain the greatest amount of compression for the least incremental cost. In fast tracking, the activities that are generally performed in a sequence are performed in parallel which increases risk and can also result in rework.
- Control Schedule: The process includes determining the current status of the project schedule, influencing factors that can create schedule changes, and managing the actual changes to the baseline as they occur.