Unit 2 Time Management Prepared by: Prof. Seemaah Keddar

Time Management

Activity Definition

Tools and Techniques for Activity Definition

Outputs from Activity Definition

Activity Sequencing

Inputs to Activity sequencing

Tools and Techniques for Activity sequencing

Output from Activity sequencing

Activity Duration Estimation

Inputs to Activity Duration Estimation

Tools and Techniques for Activity Duration Estimation

Schedule Development

Inputs to Schedule Development

Tools & Techniques for Schedule Development

Critical path method (CPM) It is Network analysis technique used in complex project plans with a large number of activities. CPM diagrams (1) all activities, (2) time required for their completion, (3) and how each activity is related to the previous and next activity. A sequence of activities is called a 'path,' and the longest-path in the diagram is the critical path. It is 'critical' because all activities on it must be completed in the designated time, otherwise the whole project will be delayed.

CPM Example: Activity Description Required Predecessor Duration A Product design (None) 5 months B Market research (None) 1 C Production analysis A 2 D Product model A 3 E Sales brochure A 2 F Cost analysis C 3 G Product testing D 4 H Sales training B, E 2 I Pricing H 1 J Project report F, G, I 1. Example 1 Step 2: Draw the diagram Draw by hand a network diagram of the project that shows which activities follow which other ones. This can be tricky. The analysis method we'll be using requires an "activity-on-arc" (AOA) diagram. An AOA diagram has numbered "nodes" that represent stages of project completion. You make up the nodes' numbers as you construct the diagram. You connect the nodes with arrows or "arcs" that represent the activities that are listed in the above table.

CPM Some conventions about how to draw these diagrams: All activities with no predecessor come off of node 1. All activities with no successor point to the last node, which has to have highest node number. u connect the nodes with arrows or "arcs" that represent the activities that are listed in the above table.

Graphical Evaluation and Review Technique (GERT) There is one additional mathematical analysis method that is rarely used today because it has been proven to be less accurate than PERT and CPM. This method is the graphical evaluation and review technique (GERT). GERT allows for probabilistic treatment of both network logic and activity duration estimates. GERT is mainly used on project activities that are only performed in part, as well as those activities that may be performed more than once (loop). The above graphic illustrates a GERT diagram with a simple loop. For example, on a high-rise development project, the electrical outlets for each floor may be installed as each floor is completed instead of waiting for the completion of the entire building. Since this activity will be performed more than once, using GERT will enable you to calculate the entire duration of this activity.

PERT chart (Program Evaluation Review Technique) There is one additional mathematical analysis method that is rarely used today because it has been proven to be less accurate than PERT and CPM. This method is the graphical evaluation and review technique (GERT). GERT allows for probabilistic treatment of both network logic and activity duration estimates. GERT is mainly used on project activities that are only performed in part, as well as those activities that may be performed more than once (loop). The above graphic illustrates a GERT diagram with a simple loop. For example, on a high-rise development project, the electrical outlets for each floor may be installed as each floor is completed instead of waiting for the completion of the entire building. Since this activity will be performed more than once, using GERT will enable you to calculate the entire duration of this activity.

PERT Example The Program Evaluation and Review Technique (PERT) is a project scheduling technique to analyze and represent the tasks involved in completing a given project. It incorporates activity duration variability and relies on similar concepts as the critical path method. Table 1: An example project for PERT calculations

PERT Example Activity Duration Estimates Activity durations are based on estimates made by human beings and are therefore error-prone. In PERT, the technique requires three duration estimates for each individual activity, as follows: Optimistic time estimate (a): This is the shortest possible time in which the activity can be completed, and assumes that everything has to go perfect Realistic time estimate (m): This is the most likely time in which the activity can be completed under normal circumstances Pessimistic time estimate (b): This is the longest possible time the activity might require, and assumes a worst-case scenario

PERT Example The project network and the (average) critical path

Tools & Techniques for Schedule Development

4. In project management, resource leveling is a technique in which start and finish dates are adjusted based on resource constraints with the goal of balancing demand for resources with the available supply.

Tools & Techniques for Schedule Development

Outputs from Schedule Development

Schedule Control

Tools and Techniques for Schedule Control

Outputs from Schedule Control