MBA management

Project Scheduling

Scheduling means the allocation of time period to tasks. Determining the sequence of tasks with time period, start and finish time is known as scheduling. When preparing a schedule estimate, consider that transition between activities often takes time. Organizations or resources outside your direct control may not share your sense of schedule urgency, and their work may take longer to complete. Beware of all external dependency relationships. Uncertain resources of talent, equipment, or data will likely result extending the project schedule.

Developing the Project Schedule

The project manager specifically pursues the start date, and more importantly, the completion date. Projects that don’t provide realistic schedules aren’t likely to get approved. Or worse, the projects will get approved, but thy will most likely fail, as the project tam will not be able to meet the unrealistic schedule.

Creating the Project Schedule

The project manager, the project tam, and possibly vent h key stakeholders, will examine the inputs, and apply the techniques to create a feasible schedule for the project. The point of the project schedule is to complete the project scope in the shortest amount of time possible without incurring exceptional costs, risks, or a loss of quality.

Crafting the project schedule is part of the planning process group. It is calendar based and relies on both the project network diagram and the accuracy of time estimates.

Examining the Project Schedule

The project schedule includes, at a minimum, a date for when the project begins and a date when the projects is expected to end. The project schedule is considered proposed until the resources needed to complete the project work are ascertained. In addition to the schedule, the project manager should include all of the supporting details. Project schedules can be presented in many different formats, such as:

• Milestone charts plot out the high-level deliverables and external interfaces, such as a customer walkthrough, against a calendar. Milestone charts are similar to a Gantt chart, but with less details regarding individual activities.

• Project Network Diagram Illustrates the flow of work, the relationship between activities, the critical path, and the expected project end date. PNCDs, when used as the project schedule, should have dates associated with each project activity to show when the activity is expected to start and end.

• Bar charts: These show the start and end dates for the project, and the activity duration against a calendar. They are easy to rad. Scheduling bar charts are also called Gantt charts.

Controlling the Project Schedule

Schedule control is part of integrated change management. Throughout a typical project, events will happen that may require updates to the project schedule. Schedule control is concerned with three processes.

• The project manager works with the factors that can cause schedule change in an effort to confirm that the changes are agreed upon. Factors can include project team members. Stakeholders, management, customers, and project conditions.

• The project manager examines the work results and conditions to determine whether the schedule has changed.

The project manager manages the actual change in the schedule.

Applying a Schedule Control System

A schedule control system is a formal approach to managing changes to the project schedule. It considers the conditions, reasons, requests, costs, and risks of making changes. It includes methods of tracking changes, approval levels based on thresholds, and the documentation of approved or declined changes. The schedule control system is part of integrated change management.

Measuring Project Performance

Poor performance may result in schedule changes. Consider a project team that is completing a work on time, but all of the work results are unacceptable. The project team may be rushing through their assignments to meet their deadline. To compensate for this, the project may be changed to allow for additional quality inspections, and more time for activity completion. Project performance is often based on earned value management.

Examining the Schedule Variance

The project manager must activity monitor the variances between when activities are scheduled to end and when thy actually end. And accumulation of differences between scheduled and actual dates may result in a schedule variance. The project manager must also pay attention to the completion of activities on paths with float, not just the critical path. Consider a project that has eight different paths to completion. The project manager should first identify the critical path, but should also identify the float on each path. The path with the largest float. As activities are completed, the float of each path should be monitored to identify any paths that may be slipping from scheduled end dates.

Updating the Project Schedule

So what happens when a schedule change occurs? The project manager must ensure that the project schedule is updated to reflect the change, document the change, and follow the guidelines within the schedule management plan. Any formal processes, such as notifying stakeholders or management, should be followed.

Revisions are a special type of project schedule change, which cause the project start date, and more likely, the project end date to be changed. They typically stem from project scope changes. Because of the additional work the new scope requires, additional time is needed to complete the project.

Schedule delays, for whatever reason, may be so drastic that the entire project has to be rebase lined. Rebase lining is a worst- case scenario and should only be used when adjusting for drastic, long delays. When rebase lining happens, all of the historical information up to the point of the rebase line is eliminated. Schedule revision is the preferred, and most common, approach to changing the project end date.

Examining the Sequencing Outputs

There are many approaches to using activity sequencing: a project manager and thee project team can use software programs, the approach can be done manually, or the team can manually do the scheduling and then transfer the schedule into a PMIS. Whichever method is selected, the project manager must remember four things:

• Only the required work should be scheduled.
• Finish-to-start relationships are the most common and preferred.
• Activity sequencing is not the same as a schedule.
• Scheduling comes after activity sequencing.

Creating Network Diagrams

Network diagrams visualize the project work. A network diagram shows the relationship of the work activities and how it will progress from start to completion. Network diagrams can be extremely complex or easy to create and configure. Most network diagrams in todays’ project management environment use an approach called “activity- on- node” to illustrate the activities and the relationship between those activities and their relationships.

Precedence Diagramming Method

The precedence diagramming method (PDM) is the most common method of arranging the project work visually. The PDM puts the activities in boxes, called nods, and connects the boxes with arrows. The arrows represent the relationship and the dependencies of the work packages. The following illustration shows a simple network diagram using PDM.

Relationships between activities in a PDM constitute one of four different types

Finish –to–start(FS) This relationship means Task A must complete before Task B can begin. This is the most common relationship. For example, the foundation must set before the framing can begin.

Start-to-start(SS) This relationship means Task A must before Task B can Start. This relationship allows both activities to happen in tandem. For example, a crew of painters is painting a house. Task A is to scrape the flecking paint off the house and Task B is to prime the house. The workers scraping the house must start before the other workers can begin priming the house. All of the scraping doesn’t have to be completed before the priming can start, just some of it.

Finish-to-finish(FF) This relationship means Task A must complete before Task B dos. Ideally, two tasks must finish at exactly the same time, but this is not always the case. For example, two teams of electricians may be working together to install new telephone cables throughout a building by Monday morning. Tam A is pulling the cable to ach office. Tam b, meanwhile, is connecting the cables to wall jacks and connecting the telephones. Team A must pull the cable to the office so Tam B can complete their activity. The activities end to complete at nearly the same time, by Monday morning, so the new phones are functional.

Start-to-finish(SF) This relationship is unusual and is rarely used. It requires that Task A start so that Task B may finish. Such relationships may be encountered in construction and manufacturing. It is also known as just-in-time (JIT) scheduling. An example is a construction of a shoe store. The end of the construction is soon, but an extract date is not known. The owner of the shoe store doesn’t want to order the shoe inventory until the completion of the construction is nearly complete. The start of the construction tasks dictates when the inventory of the shoes is ordered.

Dependency Determination

Dependency determination is a method to determine how each activity in a project is depending on its predecessors or successor activity. There can be three types of dependency between the activities. They are:

- Mandatory dependencies
- Discretionary dependencies
- External dependencies

Mandatory dependencies
Mandatory dependencies are those that are inherent in the activity being done or required by the contract. They often involve physical limitations. On a construction project, it is impossible to erect the superstructure until the foundation has been laid; On an electronics Project, a prototype must be built before it can be tested. Mandatory dependencies are also called hard logic.

Discretionary dependencies
Discretionary dependencies are those that are defined by the project management team. Discretionary dependencies can also be called as preferred logic, preferential logic, or soft logic.

They should be used with care (and fully documented), since they can scheduling options later. Discretionary dependencies are usually based on:

--- “Best practices “ within a particular application area.
--- Some unusual aspect of the project, where a specific sequence is desired, even though there are other acceptable sequences.

External dependencies
External dependencies are those that involve a relationship between project activities and non-project activities. For example, the testing activity in a software project may be dependent on delivery of hardware from an external source, or environmental hearings may need to be held before site preparation can begin on a construction project.

Applying Lead & Lags
Lad time represents the time duration by which the succeeding activity can start before the completion of the preceding activity. For example, an activity in a finish-to-start dependency with a 10 day lag, the successor activity cannot start until 10 days after the predecessor has finished.

Lag time represents the time delay between the preceding activity and the commencement of the succeeding activity. For example, an activity in a finish-to-start dependency with a 10 day lad, the successor activity can start 10 days before the predecessor has finished.

Lead & Lag time is presumed to be zero if not indicated. Lead & Lag time between events can be expressed in either days or percentage of duration. The project management team determines the dependencies that may require lead or lag to define the logical relationship accurately between the activities.

CPM- Critical Path Method

Critical path method was developed by Mr. Walker in the year 1956. It is used for optimizing resource allocation and minimizing overall cost for a given project. CPM was developed to help scheduling. The relation between the amount of resources employed and the time needed to complete the project is also assumed to known.

CPM provides the following benefits:

• Provides a graphical view of the project.
• Predicts the time required to complete the project.
• Shows which activities are critical to maintaining the schedule and which are not.

Steps in CPM Project Planning

1. Specify the individual activities.
2. Determine the sequence of those activities.
3. Draw a network diagram.
4. Estimate the completion time for each activity.
5. Identify the critical path(longest path through the network).
6. Update the CPM diagram as the project progresses.

1. Specify the Individual Activities
From the work breakdown structure, a listing can be made of all the activities in the project. This listing can be used as the basis for adding sequence and duration information in later steps.

2. Determine the Sequence of the Activities
Some activities are dependent on the completion of others. A listing of the immediate predecessors of each activity is useful for constructing the CPM network diagram.

3. Draw the Network Diagram
Once the activities and their sequencing have been defined, the CPM diagram can be drawn. CPM originally was developed as an activity on node (AON) network.

4. Estimate Activity Completion Time
The time required to complete each activity can be estimated using past experience or the estimates of knowledgeable persons. CPM is a deterministic model that does not take into account variation in the completion time, so only one number is used for an activity’s time estimate.

5. Identify the Critical Path
The critical path is the longest-duration path through the network. The significance of the critical path is that activities that lie on it cannot be delayed the project. Because of its impact on the entire project, critical path analysis is an important aspect of project planning.

The critical path can be identified by determining the following four parameters for ach activity:

• ES- earliest start time: the earliest time at which the activity can start given that its precedent activities must be completed first.

• EF- earliest finish time, equal to the earliest start time for the activity plus the time required to complete the activity.

• LF- latest finish time: the latest time at which the activity can be completed without delaying the project.

• LS- Latest start time, equal to the latest finish time minus the time required to complete the activity.

Crashing and Fast Tracking

In some instances, the relationship between activities cannot be changed due to hard or soft logic. The relationship must remain as scheduled. Now consider the same construction company that is promised a bonus if they can complete the work by the end of month seven. Now there‘s incentive to complete the work, but there’s also the fixed relationship between activities.

To apply duration compression, the performing organization can rely on two different methods. These methods can be used independently or together and are applied to activities or the entire project based on need, risk, and cost. The methods are:

Crashing: This approach adds more resources to activities on the critical path to complete the project earlier. When crashing a project, costs are added as the labor expenses increase.

Crashing doesn’t always work. Consider activities that have a fixed duration and won’t finish faster with additional resources. The project manager must also consider the expenses in relation to the gains of completing on time. For example, a construction company may have been promised a bonus to complete the work by a preset date, but the cost incurred to hit the targeted date is more than what the bonus offers.

Efforts to accelerate a project schedule are commonly grouped under the term” crashing” the schedule. May be this term was coined to suggest that there is always some price for driving a project to completion sooner than normal. There are a number of ways to improve the schedule when the work needs to be finished quickly.

1. Add people to the schedule. Additional staff must be added early in a project or they will slow it down while learning the ropes. If you add people, you may also need to add staff for supervision and coordination, so staff are fully applied.

2. Improve productivity and work longer hours. A good team atmosphere with management support can help make this happen. Without positive nourishment of this process, you could lose your team to attrition.

3. Review schedule dependencies and look for opportunities to overlap tasks or make serial tasks concurrent or parallel activities. This requires greater coordination and sometimes involves increased risks which need to be managed carefully.

4. Review the project scope and remove or delay features or functionality from the project critical path.

5. Consider innovative approaches such as a different development methodology, alternative technologies, or out-sourcing options.

Fast Tracking: This method changes the relationship of activities. With fast tracking, activities that would normally be done in sequence are allowed to be done in parallel or with some overleap. Fast tracking can be accomplished by changing the relation of activities from FS to SS or by adding lead time to downstream activities. For example, a construction company could change the relationship between painting the rooms and installing the carpet by adding lead time to the carpet installation task. Before the change, all of the rooms had to be painted before the carpet installers could begin. With the added lad time, the carpet can be installed hours after a room is painted. Fast tracking increases risk and may cause rework in the project.

Earned Value Management or Earned Value Analysis

Earned Value Management (EVM) is the measurement monitoring and control of project progress in terms of cost, time and scope against an agreed and fully integrated baseline plan. It is a proven process that provides strong benefits for the control of projects. It facilitates the integration of project scope, time and cost objectives and the establishment of a baseline plan against which performance can be measured during the execution of a project.

EVM has the unique ability to combine measurements of work performance (completion of planned work), schedule performance (behind or ahead of schedule), and cost performance ( below or above budget) within a single integrated methodology. Furthermore, it provides a sound basis for early problem identification, corrective actions, and management re-planning as required. The use of EVM improves the delivery of projects.

History of EVM

The origin of EVM was in industrial manufacturing at the turn of the 20th century, but the idea took root in the United States Department of Defense in the 1960s.The original concept was called PERT/COST.

In 1967, the U.S. Department of Defense (DOD) established a criterion based approach, using a set of 35 criteria, called the Cost? Schedule Control Systems Criteria (C/S CSC). In 1970s and early 1980s, a sub culture of C/SSC analysis grew, but the technique was often ignored or even actively resisted by project managers in both government and industry. C/SCSC was often considered a financial control tool that could be delegated to analytical specialists.

In the late 1980s and early 1980s, EVM emerged as a project management methodology to be understood and used by managers and executives, not just EVM specialists.

In the 1990s, many US Government regulations were eliminated or streamlined. However, EVM not only survived the acquisition reform movement, but become strongly associated with the acquisition reform movement itself. Most notably, from 1995 to 1980, ownership of EVM criteria (reduced to 32) was transferred to industry by adoption of ANSI EIA 748- A standard.

Many industrialized nations also began to utilize EVM. Closer integration of EVM with project management profession accelerated in the 1990s.

An overview of EVM was included in PMBOK GuideR First Edition in 1987 and expanded in subsequent editions. Efforts to simplify and generalize EVM gained momentum in the early 2000s.

Basic concepts of EVM

The basic concepts of EVM are

• All project steps “earn” value as work is completed.

• The Earned Value (EV) can then be compared to actual costs and planned costs to determine project performance and predict future performance trends.

• Physical progress is measured in dollars, so schedule performance and cost performance can be analyzed in the same terms.

As per ANSI EIA 748-a, there are 32 criteria which forms the EVM system. Thy are grouped under 5 groups; namely

1. Organization Criteria
2. Planning, Scheduling and Budgeting Criteria
3. Accounting Criteria
4. Analysis Criteria
5. Revision Criteria

Benefits of using EVM

In a typical project performance analysis, Physical progress is not taken into account when analyzing cost performance. Instead, the project’s actual costs spend to date are simply compared against the planned costs. This often gives misleading results.

EVM promises to improve the definition of project scope, prevent scope creep, communicate objective progress to stakeholders, and keep the project team focused on achieving progress.

EVM determines how much of a project has been completed at specific points in time, known as milestones.

EVM allows senior management to monitor progress and to react to poor performance.

Using EVM, senior management can tell early in the life of a project whether it is likely to meet its targets. Management can then decide whether to abandon the project early on, before a huge amount of money has been spent.

Likewise, if senior management’s expectations are unrealistic, EVM will quickly highlight the problem.

For the project manager, the project manager knows how the project is performing at any given time.

Measuring the performance of individual tasks rather than the project as a whole gives both the project manager and senior management a steady stream of signals about the health of the project.

Planned Value(PV)
The authorized budget assigned to the scheduled work to be accomplished for a scheduled activity or WBS component. This is also referred as Budgeted Cost of Work Scheduled (BCWS).

Earned Value(EV)
The value of the work completed expressed in terms of the approved budget assigned to that work. This is also referred as Budgeted cost of Work performed (BCWP).

Actual Cost(AC)
The total cost actually incurred and recorded in accomplishing a work performed for a scheduled activity or WBS component. This is also referred as Actual Cost of Work Performed (ACWP).

Estimate at Completion(EAC)
The estimated total cost of a schedule activity, a WBS component or the project. EAC is equal to the Actual cost(AC) plus the Estimate to Complete (ETC).

Estimate to complete(ETC)
The expected cost required to complete the remaining work of a scheduled activity or WBS component or the project.

Cost Variance(CV)
It is the Algebra difference between earned value(EV) and Actual Cost. A positive value of cost variance indicates a favorable condition and a negative value indicates an unfavorable condition.

Cost Performance Index (CPI)
It is a measure of Schedule performance on a project .It is the algebraic difference between the earned value (EV) and the Planned value (PV).

Schedule Performance Index (SPI)
It is a measure of schedule efficiency in a project. It is the ratio of earned value Earned Value (EV) to Planned value (PV). An SPI of equal to or greater than 1 indicates a favorable condition and a value less than one indicates an unfavorable condition.

Budget At completion (BAC)
The sum of all the budget established for the work to be performed on a project or a WBS component or a scheduled activity.

To Complete Performance Index (TCPI)
It is the calculated projection of cost performance that must be achieved on the remaining work to meet a specified management goal, such as the budget at completion (BAC) or estimate at completion (EAC). It is the ratio of remaining work to the funds remaining.

Understanding EVM
Assume you are in a project of constructing a fence around a four-sided field. You have estimated that the project would cost you USD 4000 and the time required to complete the project is 4 weeks.

The project has four scheduled activity of constructing fence on each side with one week duration. The cost of each activity is estimated to be USD 1000.
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Review Questions
  • 1. What do you mean by project scheduling? How will you create it?
  • 2. What are the ways in which a project schedule can be presented?
  • 3. Write short notes on the following;

    a) Schedule control system b) Updation of project schedule
    c) Network diagrams
    d) Crashing
    e) Fast Tracking
    f) Earned Value Analysis
  • 4. What is CPM? What are its features?
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