SPM chapter 06 - Activity Planning by Bob Hughes
- 4. Introduction A detailed project must include a schedule indicating the start and completion times for each activity. So that….
- 5. Introduction ● Ensure resources will be available when required. ● Avoid different activities competing for the same resources at the same time. ● produce a detailed schedule showing which staff carry out each activity. ● produce a detailed plan against which actual achíevement may be measured. ● produce a timed cash flow forecast. ● replan the project during its life to correct drift from the target.
- 6. Introduction The starts and completions of activities must be clearly visible and this is one of the reasons why it is advisable to ensure that each and every project activity produces some tangible product or 'deliverable’.
- 7. Objectives ● Feasibility assessment. ● Resource allocation. ● Detailed costing. ● Motivation. ● Co-ordination
- 8. Objectives ● Feasibility assessment. ○ ls the project possible within required timescales and resource constraints? ● Resource allocation. ○ What are the most effective ways of allocating resources to the project. ○ When should the resources be available? ○ The project plan allows us to investigate the relationship between timescales and resource availability
- 9. Objectives ● Detailed costing. ○ How much will the project cost and when is that expenditure likely to take place? ○ After producing an activity plan and allocating specific resources, we can obtain more detailed estimates of costs and their timing. ● Motivation. ○ Providing targets and being seen to monitor achievement against targets is an effective way of motivating staff ● Coordination ○ When do the staff in different departments need to be ○ available to work on a particular project and when do staff need to be ○ transferred between projects?
- 10. Objectives Activity planning and scheduling techniques place an emphasis on completing the project in a minimum time at an acceptable cost or, alternatively, meeting a set target date at minimum cost
- 11. When to plan? Planning is an ongoing process of refinement, each iteration becoming more detailed and more accurate than the last. ● Feasibility study ○ Estimate timescale. ○ Risk of not achieving the target completion date. ○ Keeping within budget. ● Activity plan ○ Resource availability ○ Cash-flow control.
- 12. Project schedule Before work commences on a project or, possibly, a stage of a larger project, the project plan must be developed to the level of showing dates when each activity should start and finish and when and how much of each resource will be required. Once the plan has been refined to this level of detail we call it a project schedule
- 13. Project schedule Creating a project schedule comprises four main stages. 1. What activities need to be carried out and in what order they are to be done. From this we can construct an ideal activity plan. 2. The ideal activity plan will then be the subject of an activity risk analysis, aimed at identifying potential problems. This might suggest alterations to the ideal activity plan and will almost certainly have implications for resource allocation 3. The third step is resource allocation. The expected availability of resources might place constraints on when certain activities can be carried out, and our ideal plan might need to be adapted to take account of this. 4. The final step is schedule production, Once resources have been allocated to each activity, we will be in a position to draw up and publish a project schedule, which indicates planned start and completion dates and a resource requirements statement for each activity.
- 14. Projects and activities ● A project ○ is composed of a number of interrelated activities. ○ may start when at least one of its activities is ready to start. ○ will be completed when all of the activities have been completed
- 15. Projects and activities ● An activity ○ Must have a clearly defined start and end-point. ○ lf an activity requires a resource (as most do) then that resource requirement must be forecastable and is assumed to be required at a constant level throughout the duration. ○ The duration of an activity must be forecastable. ○ Some activities might require that others are completed before they can begin (these are known as precedence requirements).
- 16. Identifying activities ● Three approaches ○ The activity-based approach ○ The product-based approach ○ The hybrid approach
- 17. 1. Activity Based approach ● Consists of creating a list of all the activities that the project is thought to involve. ● Require a brainstorming session of whole team. ● It might be helpful to subdivide the project into the main life-cycle stages and consider each of these separately.
- 19. 2. Product Based approach ● lt consists of producing a Product Breakdown Structure and a Product Flow Diagram. ● The PFD can therefore be easily transformed into an ordered list of activities by identifying the transformations that turn some projects into others
- 20. 3. Hybrid approach A WBS may be based upon the project's products as which is in turn based on a simple list of final deliverables and, for each deliverable, a set of activities required to produce that product.
- 21. 3. Hybrid approach IBM recommend that the following five levels should be used in a WBS Level 1: Project. Level 2: Deliverables such as software/ manuals and training courses. Level 3: Components, which are the key work items needed to produce deliverables, such as the modules and tests required to produce the system software. Level 4: Work-packages, which are major work items, or collections of related tasks, required to produce a component. Level 5: Tasks, which are tasks that will normally be the responsibility of a single person.
- 23. Sequencing and scheduling activities
- 24. Sequencing and scheduling activities ● The chart shown has been drawn up taking account of the nature of the development process(that is, certain tasks must be completed before others may start) ● Availability of resources (for example, activity C follows activity B because Andy cannot work on both tasks at the same time). ● have sequenced the tasks (that is, identified the dependencies among activities) and schedule them (that is specified when they should take place)
- 25. 6.7 Network planning models ● These project scheduling techniques model the project's activities and their relationships as a network ● In the network, time flows from left to right (CMP, PERT) ● Now the most popular variation is precedence networks ● This method uses activity-on-node networks where activities are represented as nodes and their links between nodes represent precedence (or sequencing) requirements.
- 27. 6.8 Formulating a network model ● The first stage in creating a network model is to represent the activities and their interrelationships as a graph. ● ln activity-on-node we do this by representing activities as nodes (boxes) in the graph - the lines between nodes represent dependencies.
- 28. Constructing precedence networks ● A project network should have only one start node Although it is logically possible to draw a network with more than one starting node( source of confusion). ln such cases it is normal to invent a 'start activity’ which has zero duration but may have an actual start date ● A project network should have only one end node, a project may finish only once! Although it is possible to draw a network with more than one end node. Where the completion of a project depends upon more than one 'final' activity it is normal to invent a 'finish' activity.
- 29. Constructing precedence networks ● A node has duration A node represents an activity and, in general, activities take time to execute. ● Links normally have no duration Links represent the relationships between activities. ● Precedents are the immediate preceding activities. ● ln Figure 6.9, the activity 'Program test' cannot start until both 'Code' and 'Data take-on' have been completed and activity 'Install' cannot start until 'Program test' has finished
- 31. Constructing precedence networks ● 'Code' and 'Data take-on' can therefore be said to be precedents of 'Program test', and 'Program test' is a precedent of 'Install' ● A network may not contain loops. (Iteration but not in Network.)
- 32. Constructing precedence networks ● A network should not contain dangles
- 33. Constructing precedence networks ● A network should not contain dangles
- 35. Adding the time dimension The critical path approach is concerned with two primary objectives: ● planning the project in such a way that it is completed as quickly as possible; ● and identifying those activities where a delay in their execution is likely to affect the overall end date of the project or later activities' start dates. The method requires that for each activity we have an estimate of its duration
- 36. Adding the time dimension The network is then analysed by carrying out: A forward pass, to calculate the earliest dates at which activities may commence and the project be completed, and a backward pass, to calculate the latest start dates for activities and the critical path.
- 37. Adding the time dimension
- 38. Adding the time dimension
- 39. The forward pass
- 41. Identifying the critical path There will be at least one path through the network that defines the duration of the project. This is known as the critical path. The difference between an activity’s earliest start date and its latest start date ( or the difference between its earliest and latest finish dates) is known as the activity’s float. It is a measure of how much the start or completion of an activity may be delayed without affecting the end date of the project. Any activity with zero float is critical in the sense that any delay in carrying out the activity will delay the completion date of the project as a whole. There will always be at least one path through the network joining those critical activities this path is known as the critical path
- 42. Identifying the critical path The significance of the critical path is two-fold. ● ln managing the project, we must pay particular attention to monitoring activities on the critical path so that the effects of any delay or resource Unavailability are detected and corrected at the earliest opportunity ● ln planning the project, it is the critical path that we must shorten if we are to reduce the overall duration of the project.
- 43. Activity float Free float: The time by which an activity may be delayed without affecting any subsequent activity. ● Free Float of current activity = (ES)S – (EF)C Where S = Successor Activity and C = Current Activity ● Free float = ES (next task) - EF (current task) Interfering float: The difference between total float and free float.