[MUSIC] In this module, we will be doing project planning and particularly how work breakdown structure and the network diagram. We will concentrate on planning, which is the second phase of the project lifecycle. Planning starts with what is called work breakdown structure. Essentially, we'll be getting into more details about the project in terms of the associated activities, technological precedence relationships, network diagram. Estimation of the duration of the activities and scheduling of the activities. In this module, we will not variable resources required to perform each activity. In essence, we assumed that the necessary resources would be available as they've been required. In a later module, we'll consider a case where the available resources are limited. In the initiation phase, the project is broken down with milestones, deadlines and deliverables. In this phase, the deliverables are first broken down into subdeliverables which in turn are broken down further until you have the lowest subdeliverables. In essence, the entire project work is successively broken down into tasks and subtasks until you get work packages are tasks which are typically referred to as activities that constitute the actual work to be done. The process of identifying the activities is referred to as work breakdown structure and the work package are activities that represent the lowest level of the work breakdown structure. A work breakdown structure is essentially a hierarchical breakdown of the work involved in completing the project. In identifying the activities, one has to be careful that the activity is not too much of an aggregation of several sub activities. While at the same time, the activity should not be minute in details, such as tightening the screw and so on. While identifying the activities, we should also identify the so called technological dependencies. In that, an activity maybe started only after some other activity has been completed. For instance, the construction of a building, foundation work needs to be completed before the flooring and walls are built. These dependencies are captured in the so-called precedent relationships between activities. The precedence relationships that we are concerned with are the so-called immediate precedence relationships. For instance, suppose B can start only after A has been completed and activity C can start only after B is completed. In this says, clearly in order for activity C to start both activities in, we must have been completed, but in terms of immediate present relationships while activity A and immediate predecessor of activity B. For activity C, only activity B is an immediate predecessor. Since we are only interested in immediate precedence relationships, we drop the word immediate. And then for, whenever we talk about precedence relationships, we'll be referring only to immediate predecessors. Once the activities on the precedence relationships are identified, we can drop the so-called network diagram. A network consists of circles or rectangles called nodes connected by lines with arrows. There can be at most one line connecting two nodes. There are two types of network diagrams, depending upon whether the nodes represent activities or the lines with arrows represent activities. The latter representation, the lines with arrows representing the activities may be more appealing in that the activities consume time and lines with arrows may be thought of as consuming time. But unfortunately, in this representation, in order to show the precedence relationships accurately, you may have to use dummy activities which are not really activities connected with the project and do not consume any time. Moreover, this representation of the project is not unique, because there could be more than one way of using the dummy activities to correctly represent the president's relationships. By far, the most popular type of network diagram is the one in which the nodes represent activities and the lines with arrows connecting the different nodes represent the precedence relationships. Given the activities and the precedence relationships, this network representation of the project is unique. Henceforth, we'll only be considering network diagrams in which the nodes represent activities and the lines with arrows connecting two nodes represent the precedence relationships. It is important to note that you cannot have loops as shown in the diagram. If there's a loop in the diagram, you have a conflict leading to an impasse. In this case, the president relationship state that activity B can be started only after activity A has been completed. Activity C can be started only after B has been completed. And finally, activity A can be started only after activity C has been completed. In effect, none of the activities, A, B and C can be started. Each node representing an activity must have a unique number or identification. Next, we look at some practices in drawing the network diagram. If the nodes are numbered, the numbering of the activities is usually from left to right. At the start of the project, suppose several activities can be done simultaneously. A dummy start activity may be added and it will be the predecessor of all the activities that can be started simultaneously at the beginning of the project. Similarly, in the completion of several different activities, constitutes the completion of the project. A dummy finish activity may be added and all activities that constitute the completion of the project are activities that do not have a success with predecessors of this dummy finish activity. If this convention is followed, there will only one start activity and one finished activity. Next, let us look at a simple software development example to see how we can draw the network. The examples we'll consider are simple. So I say, let's start the concepts it would be applicable even in large real world projects. For this project, we have identified eight activities as shown in the table. For convenience of our presentation, date activities are referred to as activities A to H respectively. The first activity to start the project is design specifications. The second, third and fourth activities are respectively. Prepare software, which is activity B. Design Test cases, which is activity C. Prepare layout for Manual, which is Activity D. All these activities have activity A as the predecessor. The fifth activity, which is activity E is test software. This has activities B and C as its predecessors, and the sixth activity shown as activity F is finalized software for which activity E is its predecessor. The seventh activity, which is activity G is finalize manual which has activities D and F as its predecessors. The last activity that would complete the project is release software and manual with activity G as it predecessor. The duration in weeks for each of the activities is given in the last column on the table. Note that it is always better to use the same unit, such as days or weeks or months, etc., for the duration of all the activities. If the duration is in weeks, it is better to mention that we are using five working days per week or it is six or seven days per week, so that the schedule in terms of calendar days can be obtained. In summary, the activity identification in the first column of the table. Description of the activities in the second column. The predecessors are given in the third column. Using the identified predecessor relationships, the network is drawn as shown. In order to draw the network, in order to acquire the durations of the activities. However, activity durations are required to find the earliest completion of the project and define a schedule for each activity. In the next module, we will look at how to arrive at a schedule for each activity using the estimated duration of each activity which is the last column of the table. In a later module, we'll see some approaches to estimating the activity durations. [MUSIC]
