Critical Path Method (CPM)

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The critical path method (CPM), or critical path analysis (CPA), is an algorithm for scheduling a set of project activities. It is commonly used in conjunction with the program evaluation and review technique (PERT). A critical path is determined by identifying the longest stretch of dependent activities and measuring the time required to complete them from start to finish.

The critical path method (CPM) is a project modeling technique developed in the late 1950s by Morgan R. Walker of DuPont and James E. Kelley Jr. of Remington Rand. Kelley and Walker related their memories of the development of CPM in 1989. Kelley attributed the term “critical path” to the developers of the Program Evaluation and Review Technique which was developed at about the same time by Booz Allen Hamilton and the U.S. Navy. The precursors of what came to be known as Critical Path were developed and put into practice by DuPont between 1940 and 1943 and contributed to the success of the Manhattan Project.

Critical Path Analysis is commonly used with all forms of projects, including construction, aerospace and defense, software development, research projects, product development, engineering, and plant maintenance, among others. Any project with interdependent activities can apply this method of mathematical analysis. The first time CPM was used for major skyscraper development was in 1966 while constructing the former World Trade Center Twin Towers in New York City. Although the original CPM program and approach is no longer used, the term is generally applied to any approach used to analyze a project network logic diagram.

The essential technique for using CPM is to construct a model of the project that includes the following:

Using these values, CPM calculates the longest path of planned activities to logical end points or to the end of the project, and the earliest and latest that each activity can start and finish without making the project longer. This process determines which activities are “critical” (i.e., on the longest path) and which have “total float” (i.e., can be delayed without making the project longer). In project management, a critical path is the sequence of project network activities which add up to the longest overall duration, regardless if that longest duration has float or not. This determines the shortest time possible to complete the project. There can be ‘total float’ (unused time) within the critical path. For example, if a project is testing a solar panel and task ‘B’ requires ‘sunrise’, there could be a scheduling constraint on the testing activity so that it would not start until the scheduled time for sunrise. This might insert dead time (total float) into the schedule on the activities on that path prior to the sunrise due to needing to wait for this event. This path, with the constraint-generated total float would actually make the path longer, with total float being part of the shortest possible duration for the overall project. In other words, individual tasks on the critical path prior to the constraint might be able to be delayed without elongating the critical path; this is the ‘total float’ of that task. However, the time added to the project duration by the constraint is actually critical path drag, the amount by which the project’s duration is extended by each critical path activity and constraint.

A project can have several, parallel, near critical paths; and some or all of the tasks could have ‘free float’ and/or ‘total float’. An additional parallel path through the network with the total durations shorter than the critical path is called a sub-critical or non-critical path. Activities on sub-critical paths have no drag, as they are not extending the project’s duration.

CPM analysis tools allow a user to select a logical end point in a project and quickly identify its longest series of dependent activities (its longest path). These tools can display the critical path (and near critical path activities if desired) as a cascading waterfall that flows from the project’s start (or current status date) to the selected logical end point.

Although the activity-on-arrow diagram (PERT Chart) is still used in a few places, it has generally been superseded by the activity-on-node diagram, where each activity is shown as a box or node and the arrows represent the logical relationships going from predecessor to successor as shown here in the “Activity-on-node diagram”.

In this diagram, Activities A, B, C, D, and E comprise the critical or longest path, while Activities F, G, and H are off the critical path with floats of 15 days, 5 days, and 20 days respectively. Whereas activities that are off the critical path have float and are therefore not delaying completion of the project, those on the critical path will usually have critical path drag, i.e., they delay project completion. The drag of a critical path activity can be computed using the following formula:

These results, including the drag computations, allow managers to prioritize activities for the effective management of project, and to shorten the planned critical path of a project by pruning critical path activities, by “fast tracking” (i.e., performing more activities in parallel), and/or by “crashing the critical path” (i.e., shortening the durations of critical path activities by adding resources).

Critical path drag analysis has also been used to optimize schedules in processes outside of strict project-oriented contexts, such as to increase manufacturing throughput by using the technique and metrics to identify and alleviate delaying factors and thus reduce assembly lead time.

Crash duration is a term referring to the shortest possible time for which an activity can be scheduled. It can be achieved by shifting more resources towards the completion of that activity, resulting in decreased time spent and often a reduced quality of work, as the premium is set on speed.
Crash duration is typically modeled as a linear relationship between cost and activity duration; however, in many cases a convex function or a step function is more applicable.

Originally, the critical path method considered only logical dependencies between terminal elements. Since then, it has been expanded to allow for the inclusion of resources related to each activity, through processes called activity-based resource assignments and resource leveling. A resource-leveled schedule may include delays due to resource bottlenecks (i.e., unavailability of a resource at the required time), and may cause a previously shorter path to become the longest or most “resource critical” path. A related concept is called the critical chain, which attempts to protect activity and project durations from unforeseen delays due to resource constraints.

Since project schedules change on a regular basis, CPM allows continuous monitoring of the schedule, which allows the project manager to track the critical activities, and alerts the project manager to the possibility that non-critical activities may be delayed beyond their total float, thus creating a new critical path and delaying project completion. In addition, the method can easily incorporate the concepts of stochastic predictions, using the program evaluation and review technique (PERT) and event chain methodology.

Currently, there are several software solutions available in industry that use the CPM method of scheduling; see list of project management software. The method currently used by most project management software is based on a manual calculation approach developed by Fondahl of Stanford University.

A schedule generated using the critical path techniques often is not realized precisely, as estimations are used to calculate times: if one mistake is made, the results of the analysis may change. This could cause an upset in the implementation of a project if the estimates are blindly believed, and if changes are not addressed promptly. However, the structure of critical path analysis is such that the variance from the original schedule caused by any change can be measured, and its impact either ameliorated or adjusted for. Indeed, an important element of project postmortem analysis is the as built critical path (ABCP), which analyzes the specific causes and impacts of changes between the planned schedule and eventual schedule as actually implemented.

Management Process

Management process is a process of setting goals, planning and/or controlling the organizing and leading the execution of any type of activity, such as:

An organization’s senior management is responsible for carrying out its management process. However, this is not always the case for all management processes, for example, it is the responsibility of the project manager to carry out a project management process.

Planning, it determines the objectives, evaluate the different alternatives and choose the best

Organizing, define group’s functions, establish relationships and defining authority and responsibility

Staffing, recruitment or placement and selection or training takes place for the development of members in the firm

directing, is to give the Direction to the employees.

Technology Management

Technology management is a set of management disciplines that allows organizations to manage their technological fundamentals to create competitive advantage. Typical concepts used in technology management are:

The role of the technology management function in an organization is to understand the value of certain technology for the organization. Continuous development of technology is valuable as long as there is a value for the customer and therefore the technology management function in an organization should be able to argue when to invest on technology development and when to withdraw.

Technology management can also be defined as the integrated planning, design, optimization, operation and control of technological products, processes and services, a better definition would be the management of the use of technology for human advantage.

The Association of Technology, Management, and Applied Engineering defines technology management as the field concerned with the supervision of personnel across the technical spectrum and a wide variety of complex technological systems. Technology management programs typically include instruction in production and operations management, project management, computer applications, quality control, safety and health issues, statistics, and general management principles.

Perhaps the most authoritative input to our understanding of technology is the diffusion of innovations theory developed in the first half of the twentieth century. It suggests that all innovations follow a similar diffusion pattern – best known today in the form of an “s” curve though originally based upon the concept of a standard distribution of adopters. In broad terms the “s” curve suggests four phases of a technology life cycle – emerging, growth, mature and aging.

These four phases are coupled to increasing levels of acceptance of an innovation or, in our case a new technology. In recent times for many technologies an inverse curve – which corresponds to a declining cost per unit – has been postulated. This may not prove to be universally true though for information technology where much of the cost is in the initial phase it has been a reasonable expectation.

The second major contribution to this area is the Carnegie Mellon Capability Maturity Model. This model proposes that a series of progressive capabilities can be quantified through a set of threshold tests. These tests determine repeatability, definition, management and optimization. The model suggests that any organization has to master one level before being able to proceed to the next.

The third significant contribution comes from Gartner – the research service, it is the Hype cycle, this suggests that our modern approach to marketing technology results in the technology being over hyped in the early stages of growth. Taken together, these fundamental concepts provide a foundation for formalizing the approach to managing technology.

Mobile device management (MDM) is the administrative area dealing with deploying, securing, monitoring, integrating and managing mobile devices, such as smartphones, tablets and laptops, in the workplace and other areas. The intent of MDM is to optimize the functionality and security of mobile devices within the enterprise, while simultaneously protecting the corporate network. MDM is usually implemented with the use of a third party product that has management features for particular vendors of mobile devices.

Modern Mobile Device Management products supports tablets, Windows 10 and macOS computers. The practice of using MDM to control PC is also known as unified endpoint management.

The Association of Technology, Management, and Applied Engineering (ATMAE), accredits selected collegiate programs in technology management. An instructor or graduate of a technology management program may choose to become a Certified Technology Manager (CTM) by sitting for a rigorous exam administered by ATMAE covering production planning & control, safety, quality, and management/supervision.

ATMAE program accreditation is recognized by the Council for Higher Education Accreditation (CHEA) for accrediting technology management programs. CHEA recognizes ATMAE in the U.S. for accrediting associate, baccalaureate, and master’s degree programs in technology, applied technology, engineering technology, and technology-related disciplines delivered by national or regional accredited institutions in
the United States.(2011)

Project Workforce Management (PWM)

Project workforce management is the practice of combining the coordination of all logistic elements of a project through a single software application (or workflow engine). This includes planning and tracking of schedules and mileposts, cost and revenue, resource allocation, as well as overall management of these project elements. Efficiency is improved by eliminating manual processes, like spreadsheet tracking to monitor project progress. It also allows for at-a-glance status updates and ideally integrates with existing legacy applications in order to unify ongoing projects, enterprise resource planning (ERP) and broader organizational goals. There are a lot of logistic elements in a project. Different team members are responsible for managing each element and often, the organisation may have a mechanism to manage some logistic areas as well.

By coordinating these various components of project management, workforce management and financials through a single solution, the process of configuring and changing project and workforce details is simplified.

A project workforce management system defines project tasks, project positions, and assigns personnel to the project positions. The project tasks and positions are correlated to assign a responsible project position or even multiple positions to complete each project task. Because each project position may be assigned to a specific person, the qualifications and availabilities of that person can be taken into account when determining the assignment. By associating project tasks and project positions, a manager can better control the assignment of the workforce and complete the project more efficiently.

When it comes to project workforce management, it is all about managing all the logistic aspects of a project or an organisation through a software application. Usually, this software has a workflow engine defined. Therefore, all the logistic processes take place in the workflow engine.

This invention relates to project management systems and methods, more particularly to a software-based system and method for project and workforce management.

Due to the software usage, all the project workflow management tasks can be fully automated without leaving many tasks for the project managers. This returns high efficiency to the project management when it comes to project tracking proposes. In addition to different tracking mechanisms, project workforce management software also offer a dashboard for the project team. Through the dashboard, the project team has a glance view of the overall progress of the project elements.

Most of the times, project workforce management software can work with the existing legacy software systems such as ERP (enterprise resource planning) systems. This easy integration allows the organisation to use a combination of software systems for management purposes.

Good project management is an important factor for the success of a project. A project may be thought of as a collection of activities and tasks designed to achieve a specific goal of the organisation, with specific performance or quality requirements while meeting any subject time and cost constraints. Project management refers to managing the activities that lead to the successful completion of a project. Furthermore, it focuses on finite deadlines and objectives. A number of tools may be used to assist with this as well as with assessment.

Project management may be used when planning personnel resources and capabilities. The project may be linked to the objects in a professional services life cycle and may accompany the objects from the opportunity over quotation, contract, time and expense recording, billing, period-end-activities to the final reporting. Naturally the project gets even more detailed when moving through this cycle.

For any given project, several project tasks should be defined. Project tasks describe the activities and phases that have to be performed in the project such as writing of layouts, customising, testing. What is needed is a system that allows project positions to be correlated with project tasks. Project positions describe project roles like project manager, consultant, tester, etc. Project-positions are typically arranged linearly within the project. By correlating project tasks with project positions, the qualifications and availability of personnel assigned to the project positions may be considered.

Good project management should:

When it comes to project workforce management, it is all about managing all the logistic aspects of a project or an organisation through a software application. Usually, this software has a workflow engine defined in them. So, all the logistic processes take place in the workflow engine.

The regular and most common types of tasks handled by project workforce management software or a similar workflow engine are:

Regularly monitoring your project’s schedule performance can provide early indications of possible activity-coordination problems, resource conflicts, and possible cost overruns. To monitor schedule performance. Collecting information and evaluating it ensure a project accuracy.

The project schedule outlines the intended result of the project and what’s required to bring it to completion. In the schedule, we need to include all the resources involved and cost and time constraints through a work breakdown structure (WBS). The WBS outlines all the tasks and breaks them down into specific deliverables.

The importance of tracking actual costs and resource usage in projects depends upon the project situation.

Tracking actual costs and resource usage is an essential aspect of the project control function.

Organisational profitability is directly connected to project management efficiency and optimal resource utilisation. To sum up, organisations that struggle with either or both of these core competencies typically experience cost overruns, schedule delays and unhappy customers.

The focus for project management is the analysis of project performance to determine whether a change is needed in the plan for the remaining project activities to achieve the project goals.

Risk identification consists of determining which risks are likely to affect the project and documenting the characteristics of each.

Project communication management is about how communication is carried out during the course of the project

It is of no use completing a project within the set time and budget if the final product is of poor quality. The project manager has to ensure that the final product meets the quality expectations of the stakeholders. This is done by good:

There are three main differences between Project Workforce Management and traditional project management and workforce management disciplines and solutions:

All project and workforce processes are designed, controlled and audited using a built-in graphical workflow engine. Users can design, control and audit the different processes involved in the project. The graphical workflow is quite attractive for the users of the system and allows the users to have a clear idea of the workflow engine.

Project Workforce Management provides organization and work breakdown structures to create, manage and report on functional and approval hierarchies, and to track information at any level of detail. Users can create, manage, edit and report work breakdown structures. Work breakdown structures have different abstraction levels, so the information can be tracked at any level. Usually, project workforce management has approval hierarchies. Each workflow created will go through several records before it becomes an organisational or project standard. This helps the organisation to reduce the inefficiencies of the process, as it is audited by many stakeholders.

Unlike traditional disconnected project, workforce and billing management systems that are solely focused on tracking IT projects, internal workforce costs or billable projects, Project Workforce Management is designed to unify the coordination of all project and workforce processes, whether internal, shared (IT) or billable.

A project workforce management system defines project tasks, project positions and assigns personnel to the project positions. The project tasks and project positions are correlated to assign a responsible project position or positions to complete each project task. Because each project position may be assigned to a specific person, the qualification and availabilities of the person can be taken into account when determining the assignment. By correlating the project tasks and project positions, a manager can better control the assignment of the workforce and complete projects more efficiently.

Project workflow management is one of the best methods for managing different aspects of project. If the project is complex, then the outcomes for the project workforce management could be more effective.

For simple projects or small organisations, project workflow management may not add much value, but for more complex projects and big organisations, managing project workflow will make a big difference. This is because that small organisations or projects do not have a significant overhead when it comes to managing processes. There are many project workforce management, but many organisations prefer to adopt unique solutions.

Therefore, organisation gets software development companies to develop custom project workflow managing systems for them. This has proved to be the most suitable way of getting the best project workforce management system acquired for the company.

Project Network

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A project network is a graph (weighted directed graph) depicting the sequence in which a project’s terminal elements are to be completed by showing terminal elements and their dependencies. It is always drawn from left to right to reflect project chronology.

The work breakdown structure or the product breakdown structure show the “part-whole” relations. In contrast, the project network shows the “before-after” relations.

The most popular form of project network is activity on node (AON) (as shown above), the other one is activity on arrow (AOA).

The condition for a valid project network is that it doesn’t contain any circular references.

Project dependencies can also be depicted by a predecessor table. Although such a form is very inconvenient for human analysis, project management software often offers such a view for data entry.

An alternative way of showing and analyzing the sequence of project work is the design structure matrix or dependency structure matrix.