Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis

Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis – Techniques of control are vital for effective management and achieving organizational goals. These techniques include financial control, quality control, inventory control, process control, strategic control, and personnel control. They involve managing financial resources, ensuring product/service quality, optimizing inventory levels, enhancing operational efficiency, aligning with strategic goals, and evaluating employee performance. By employing these control techniques, businesses can maintain quality, efficiency, and profitability for long-term success.

What are Network Techniques?

Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis – – Network techniques, such as PERT (Program Evaluation and Review Technique) and CPM (Critical Path Method), have become integral tools in the realm of management planning and control. These techniques involve breaking down a project into smaller activities and arranging them in a logical sequence. By determining the sequence and time limits for each activity, project managers can effectively plan and coordinate the various operations involved. A network diagram is then created to visualize the interdependence and relationships between these activities. The construction of such a diagram requires meticulous analysis and assessment of each project component to ensure optimal timing. In network analysis, activities are represented by arrows, denoting the operations required to achieve project goals, while events, represented by circles, signify the points in time when activities are initiated or completed. PERT and CPM are two widely recognized network techniques that aid in project management and control.

What is Program Evaluation and Review Technique (PERT ) ?

Program Evaluation and Review Technique (PERT) is an effective visual network method specifically designed for planning, monitoring, and controlling complex and unique projects. PERT offers a systematic approach that ensures project success by breaking down the entire project into smaller, manageable activities and establishing their interdependencies within a network diagram.

The process of developing a PERT involves several key steps:

1. Activity Breakdown: The project is carefully dissected into smaller activities, enabling a more granular analysis and logical sequencing of tasks.
2. Interdependency Identification: The relationships and dependencies between the activities are thoroughly examined and accurately represented in the network diagram, providing a comprehensive view of the project’s structure.
3. Time Estimation: Each activity is assigned three-time estimates: the optimistic or shortest time, the pessimistic or longest time, and the normal or most likely time. These estimates facilitate a more realistic assessment of activity durations.
4. Critical Path Determination: The critical path, the longest path in terms of time, is identified within the network diagram. It signifies the sequence of activities crucial for timely project completion. Any delays along the critical path directly impact the overall project timeline.
5. Plan Refinement: Based on the critical path analysis, the initial project plan is carefully reviewed, modified, and improved to effectively control and minimize the time required for project completion. This ensures that the project stays on track and any potential delays are mitigated.

What is Critical Path Method (CPM) ?

Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis – -Critical Path Method (CPM) is a project management technique that shares similarities with Programme Evaluation and Review Technique (PERT), but it also has some distinguishing characteristics:

1. Simplified Activity Duration: Unlike PERT, CPM assumes a constant duration for each activity. Therefore, only a single time estimate is assigned to each activity, eliminating the consideration of uncertainty in duration.
2. Emphasis on Cost: While PERT primarily focuses on time management, CPM places a greater emphasis on cost control. It enables project managers to optimize resource allocation and cost efficiency throughout the project’s execution.
3. Well-Known Activity Durations: CPM is more suitable for projects where activity durations are well-known and can be accurately estimated. It is particularly effective in scenarios where historical data or past project experiences provide reliable information for time estimation.

Applications of PERT/CPM

PERT/CPM is a highly versatile and widely used tool in project management, offering numerous applications across various industries. Some of the key areas where this technique proves beneficial are:

1. Defense Industry: PERT/CPM plays a crucial role in managing large-scale projects related to the development and production of complex weapon systems. It aids in the meticulous planning, scheduling, and coordination of activities, ensuring efficient project execution.
2. Construction Projects: The construction industry extensively relies on PERT/CPM for project management. It effectively handles building and construction projects of different sizes and complexities. By optimizing resource allocation, scheduling activities, and monitoring progress, PERT/CPM contributes to timely project completion.
3. Shipbuilding: PERT/CPM finds valuable applications in the shipbuilding sector. It assists in planning and controlling activities involved in constructing ships, including hull fabrication, equipment installation, outfitting, and testing. This ensures streamlined operations and on-time delivery.
4. Airport Infrastructure: From the construction of new airport facilities to expansion projects, PERT/CPM is instrumental in managing diverse activities such as terminal construction, runway development, installation of navigation systems, and baggage handling systems. It enables efficient coordination and timely completion.
5. Plant Construction: PERT/CPM is highly beneficial in managing the construction of new plants, such as manufacturing facilities, power plants, or refineries. It aids in organizing and sequencing activities, coordinating various contractors and suppliers, and ensuring the project progresses according to schedule.
6. Product Launches: When it comes to launching new products, PERT/CPM offers invaluable support. It helps organizations plan and coordinate critical activities involved in product development, manufacturing, marketing, and distribution. By managing timelines and dependencies, PERT/CPM ensures successful product launches.
7. Computer System Installations: PERT/CPM can be effectively utilized in managing complex computer system installations. Whether it is setting up network infrastructure, deploying hardware components, configuring software, or conducting testing, PERT/CPM facilitates smooth project execution and timely completion.

Advantages of PERT/CPM

The following are the advantages of PERT/CPM: Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis –

1. Thorough Analysis: PERT/CPM encourages managers to conduct a comprehensive analysis of all factors that can impact project completion. Proactively identifying potential obstacles, uncertainties, and inefficiencies, allows for effective planning and eliminates surprises along the way.
2. Predictive Capability: PERT/CPM serves as a valuable predictive tool for assessing the impact of schedule changes. By analyzing the network diagram, project managers can identify potential trouble spots in advance, enabling them to take preventive measures and mitigate risks effectively.
3. Focus on Critical Activities: PERT/CPM directs attention to critical activities where it is most beneficial to allocate resources or expedite progress. This approach allows for efficient resource management and effective prioritization of key tasks, ensuring that project objectives are met.
4. Continuous Review and Adaptation: PERT/CPM emphasizes the importance of ongoing review and updates based on feedback from all project levels. This promotes a culture of vigilance and adaptability, enabling timely adjustments to address emerging challenges and ensure project success.
5. Enhanced Collaboration and Communication: PERT/CPM fosters collaboration among different departments involved in the project. By visually representing task relationships and responsibilities, it facilitates improved communication, coordination, and cooperation among team members, leading to better project outcomes.
6. Clarity of Individual Roles: PERT/CPM provides individuals with a clear understanding of their roles and responsibilities within the project. Each team member can easily identify their specific tasks and how their contributions align with the project’s objectives, promoting a sense of ownership and accountability.

Limitations of PERT/CPM

The following are the limitations of PERT/CPM: Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis –

1. Estimation Challenges: One of the limitations of PERT/CPM is the inherent difficulty in accurately estimating the time and cost involved in various project activities. Estimation errors can introduce unpredictability and make the PERT chart less reliable as a control tool for effective project management.
2. Time-Centric Focus: PERT/CPM is primarily suited for projects where time plays a critical role. It shines in managing and controlling time-sensitive projects, but its applicability may be constrained when other factors, such as cost or quality hold greater significance in project outcomes.
3. Limited Applicability to Simple Projects: PERT/CPM may have limited utility in handling straightforward, routine, and repetitive projects. Its strength lies in tackling complex and unique projects that require intricate analysis and involve multiple interdependent activities. In cases of continuous processes or projects with a streamlined and predictable flow, PERT/CPM may not provide substantial advantages.

Project Evaluation and Review Technique (PERT)

Project Evaluation and Review Technique (PERT) is a procedure through which activities of a project are represented in its appropriate sequence and timing. It is a scheduling technique used to schedule, organize and integrate tasks within a project. PERT is basically a mechanism for management planning and control which provides blueprint for a particular project. All of the primary elements or events of a project have been finally identified by the PERT. In this technique, a PERT Chart is made which represent a schedule for all the specified tasks in the project. The reporting levels of the tasks or events in the PERT Charts is somewhat same as defined in the work breakdown structure (WBS).

PERT chart

The PERT chart is used to schedule, organize and co-ordinate tasks within the project. the objective of PERT chart is to determine the critical path, which comprises critical activities that should be completed on schedule. This chart is prepared with the help of information generated in project planning activities such as estimation of effort, selection of suitable process model for software development and decomposition of tasks into subtasks. Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis –

Characteristics of PERT:

The main characteristics of PERT are as following :

1. It serves as a base for obtaining the important facts for implementing the decision-making.
2. It forms the basis for all the planning activities.
3. PERT helps management in deciding the best possible resource utilization method.
4. PERT take advantage by using time network analysis technique.
5. PERT presents the structure for reporting information.
6. It helps the management in identifying the essential elements for the completion of the project within time.
7. It specifies the activities that from the critical path.
8. It describes the probability of completion of project before the specified date.
9. It describes the dependencies of one or more tasks on each other.
10. It represents the project in graphical plan form.

Advantages of PERT:

It has the following advantages : Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis –

1. Estimation of completion time of project is given by the PERT.
2. It supports the identification of the activities with slack time.
3. The start and dates of the activities of a specific project is determined.
4. It helps project manager in identifying the critical path activities.
5. PERT makes well organized diagram for the representation of large amount of data.

Disadvantages of PERT:

It has the following disadvantages : Project Planning & Scheduling using Network Techniques – PERT & CPM Analysis –

1. The complexity of PERT is more which leads to the problem in implementation.
2. The estimation of activity time are subjective in PERT which is a major disadvantage.
3. Maintenance of PERT is also expensive and complex.
4. The actual distribution of may be different from the PERT beta distribution which causes wrong assumptions.
5. It under estimates the expected project completion time as there is chances that other paths can become the critical path if their related activities are deferred.

Difference between PERT and CPM

CPM Example

CPM Example

Benefits of Using PERT and CPM

1. Effective Task Scheduling: PERT is ideal for scheduling tasks in projects and determining the critical path, which is essential for understanding project timelines.
2. Timely Decision Making: Both PERT and CPM enable project managers to make timely decisions during project execution, helping to prevent delays and ensure on-time project delivery. PERT is particularly useful for exploring different scenarios, while the critical path identified by CPM helps identify potential uncertainties.
3. Promoting Department Coordination: Using both techniques promotes coordination among project departments and facilitates decision-making for cross-functional teams by providing ample data. This analysis aids in managing the project within budget constraints.
4. Long-Term Planning and Milestone Identification: CPM assists in long-term planning by identifying critical tasks, streamlining planning, scheduling, and project control, resulting in increased productivity and better resource management. PERT, on the other hand, identifies project milestones and task sequences visually, aiding in team comprehension. Regular updates to PERT charts throughout the project lifecycle ensure continued benefits.