INTRODUCTION In the planning phase of any project, scheduling is a critical activity. Project scheduling is the process of defining project activities, determining their sequence, and estimating their duration. To successfully complete a project, the project manager must be aware of all the activities the project entails.
The project management team manages and tracks these activities through a process of decomposition, meaning that the entire project is broken down into more manageable and controllable parts. A project manager follows a divide and conquer strategy of breaking down a project into components that can be managed and controlled more easily than the project in its entirety.
Once the project components are determined, the project management team establishes a sequence for doing the work associated with them. To help determine how to sequence these activities, the project manager considers technical constraints, safety of efficiency concerns, policies, the availability of resources, and the need to begin some task only after others are completed.
Scheduling tools, such as network diagrams, help the project manager visualize the result of this planning process, project management software packages assist by offering powerful tools to create, maintain and update these charts. In addition to defining and sequence activities, another important facet of project scheduling is assigning resources to those activities.
In most cases, resource availability plays a major role in determining the duration of a project. We are going to focus on how to define and sequence project activities. We are going to discuss the brief overview of the importance and challenges associated with project scheduling.
The subsequent section discusses specific techniques for breaking down a complex project into more manageable components and then determining the sequence of activities for accomplishing those components The first step in this process is the creation of a work breakdown structure (WBS), a chart detailing the projects specific components.
The second step is to determine which activities are needed to complete those project components. The third step is to determine how to sequence these activities. Throughout this discussion we will highlight the different types of diagrams used to graphically represents project schedules, their benefits and drawbacks, and how project management software can help with the different project scheduling activities.
Importance of Project Schedules Managers often cite delivering projects on time as one of their biggest challenges. Schedule issues are the main reason for conflicts on projects, especially during the second half of projects. Time has the least amount of flexibility; it passes no matter what happens on a project.
It is really possible to mention about Project Schedules in every phases of the project. Schedules are important in the control phase, when they are often used for project tracking. Without a clearly established project schedule,managers can not accurately plan activities.
Project Management Processes
Top Five Management Challenges 1. Lack of clarity in scope of the project 2. Shifting organizational priorities 3. Project changes not well managed 4. A lack of project management skills 5. Training of project sponsors
Individual Work Styles and Cultural Differences Cause Schedule Conflicts Some people prefer to follow schedules and meet deadlines while others do not. Different cultures and even entire countries have different attitudes about schedules.
Project Time Management Processes Activity definition: Identifying the specific activities that the project team members and stakeholders must perform to produce the project deliverables. Activity sequencing: Identifying and documenting the relationships between project activities. Activity resource estimating: Estimating how many resources a project team should use to perform project activities.
Activity duration estimating: Estimating the number of work periods that are needed to complete individual activities. Schedule development: Analyzing activity sequences, activity resource estimates, and activity duration estimates to create the project schedule. Schedule control: Controlling and managing changes to the project schedule.
TECHNIQUES FOR MANAGING PROJECT SCHEDULES Project managers will divide entire project into discrete activities in order to set up a schedule. These discrete activities allows them to more easily allocate time and resources, and thus better estimate how long each activities will take. This process of subdividing tasks is called Decomposition.
Creating a Work Breakdown Structure (WBS) The output that results from the process of dividing the entire project into manageable tasks (usually presentedas a hierarchival chart or in tabular form) The purpose of WBS is to serve as an aid in illustrating the projects scope and describing the activities necessary for creating various subcomponents of the project.
Work Breakdown Structure 1.0 Requirements Analysis 2.0 Stakeholder Identification 3.0 Design 4.0 Prototype Development 5.0 Testing 6.0 Implementation
WBS Inputs Scope management plan Project scope statement Project managers experiences with similiar projects Approved changes to the project scope statement.
WBS Tools and Techniques The primary technique for building a WBS is the process of decomposition. This decomposition process of breaking up a large project into smaller parts. A scheduling technique in which the team defers breaking down components until they are further clarified and the decomposition takes place as the project progresses is called Rolling wave planning.
Another method is is to use the phases of the systems development life cycle (SDLC) or project life cycle as level 1 deliverables. This method has the advantage of assisting in sequencing the different activities in later phases of the planning stage.
Work Packages The lowest level units illustrated in the WBS, used to estimate project schedule and budget. In general, and dependent upon the size of the project, a work package should be relatively short in duration; that is, the deliverable should be finishable within one or two weeks. Another recommendation for the size of the work packages is that they should all be about the same size or should require about the same efffort to produce. Finally, a work package should be specific enought to be completed by one person or a small, well-defined group.
Templates Another method of determining the deliverables and individual work packages needed to complete the project is the use of templates. Templates are lists of activities established during earlier projects.
Gantt Chart A bar chart showing the start and end dates for the activities of the project.
WBS Output WBS itself WBS dictionary (provides details about the individual components of the WBS, such as a description of each component, who is responsible for its completion, a statement of work, critical milestones, and preliminary estimates of costs or resources required.)
Activity definition In this stage, the different work packages of the WBS are broken into discrete activities, and the attributes of these activities are defined, including a description, resources requirements, logical predecesoor or successor activities, and the like.
Activity definition inputs WBS WBS dictionary The project scope statement The project management plan Organizational process assets(historical information, procedures, and policies) Enterprise environmental factors (availability of tools and resouces)
Activity Definition Tools and Techniques A central question in determining activities is, when is a sufficient level of detail reached? While there are no hard-and-fast rules for when to stop decomposition, there are a few guidelines.
Typically, an activity Can be performed by one person or a well-defined group Has a single, clearly identifiable deliverable Has a know method or technique Has well-defined predecessor and successor steps Is measurable so that the level of completion can be determined
Another guideline for determining the level of detail needed is the duration of the activity Limiting the duration of an activity to several hours or a few days, therefore, helps to limit the negative impact of any potential delays.
Also Expert judgement may be used to better define project activities based on the recollection of a project expert. For instance, a database manager knows the detailed steps to be performed in setting up certain database queries.
Activity Definition Outputs Activity list Supporting detail (such as activity attributes and milestones) Any requested changes to the project scope statement and the WBS
Activity Sequencing The process of developing a network diagram and updating activity list from the activity definition phase. A network diagram is a schematic display that illustrates the various activities in a project as well as their sequential relationships. When determining the sequencing of activities, it may be important in some instances for activities that can be performed in parallel to be scheduled simultaneously in order to speed project completion.
Activity Sequencing Inputs The activities attributes (logical predecessor or successor activities) The project scope statement The milestone list Approved change requests The product description (simply a description of the product being constructed)
Activity Sequencing Tools and Techniques The precedence diagramming method The arrow diagramming method Conditional diagramming method Network templates
Presedence Diagramming Method A network diagramming technique that uses boxes and rectangles connected by arrows to represent activities and their precedence relationships.
Four types of task dependencies
Arrow Diagramming Method A network diagram consisting of arrows to represent activities and their precedence relationships and noodes to represent milestones.
Network Template A template developed from previous projects used to shorten the development time of network diagrams.
Dependency Determination Mandatory Dependencies: Mandatory Dependencies are specific to the nature of the project work. Absolutely must happen in the described manner. Referred to as hard logic Discretionary Dependencies: Discretionary dependencies are set by the project team based on their experience. Also referred to as soft logic, preferred logic, or preferential logic. Here there may be a preferred order of events that reduces cost, risk or time, but other orders can be acceptable to the quality of the product.
External Dependencies: External Dependencies link between the project activities and activities external to the project. Leads time: The time required by one task before another task can begin Lag time: The time delay between the completion off one task and the start of the successor.
Activity Sequencing Outputs Network diagrams Updates to the activity list Updates to the activity attributes list. Further change requests