MARY GRACE MERCURIO

GANTT CHART

Gantt chart is a type of bar chart that illustrates a project schedule. Gantt charts illustrate the start and finish dates of the terminal elements and summary elements of a project. Terminal elements and summary elements comprise the work breakdown structure of the project. Some Gantt charts also show the dependency (i.e., precedence network) relationships between activities. Gantt charts can be used to show current schedule status using percent-complete shadings and a vertical "TODAY" line as shown here.

Although now regarded as a common charting technique, Gantt charts were considered revolutionary when they were introduced. In recognition of Henry Gantt's contributions, the Henry Laurence Gantt Medal is awarded for distinguished achievement in management and in community service. This chart is used also in Information Technology to represent data that has been collected.

WORK BREAKDOWN STRUCTURE

A Work breakdown structure (WBS) in project management and systems engineering, is a tool used to define and group a project's discrete work elements (or tasks) in a way that helps organize and define the total work scope of the project.
A work breakdown structure element may be a product, data, a service, or any combination. A WBS also provides the necessary framework for detailed cost estimating and control along with providing guidance for schedule development and control. Additionally the WBS is a dynamic tool and can be revised and updated as needed by the project manager.

What is a Work Breakdown Structure?

Simply put, Work Breakdown Structures are “buckets” to which cost centers are assigned, allowing Lockheed to track the costs of its PBL contracts. Below is a sample of a simple WBS structure for the creation of a bicycle. “A WBS is not a project plan, project schedule or a chronological listing. It is considered poor practice to construct a project schedule (e.g. using project management software) before designing a proper WBS. This would be similar to scheduling the activities of home construction before completing the house design. It is not possible to recover from an improperly defined WBS without starting over [citation needed], so it is worthwhile to finish the WBS design before starting a project plan or project schedule parts is not.

Logistic function or Logistic curve

A logistic function or logistic curve is the most common sigmoid curve. It models the S-curve of growth of some set P, where P might be thought of as population. The initial stage of growth is approximately exponential; then, as saturation begins, the growth slows, and at maturity, growth stops.

A simple logistic function may be defined by the formula

Where the variable P might be considered to denote a population and the variable t might be thought of as time. If we now let t range over the real numbers from to then we obtain the S-curve shown. In practice, due to the nature of the exponential function e − t, it is sufficient to compute t over a small range of real numbers such as [− 6, + 6].

The logistic function finds applications in a range of fields, including artificial neural networks, biology, biomathematics, demography, economics, chemistry, mathematical psychology, probability, sociology and statistics.

The S Curve is a well known project management tool and it consists in "a display of cumulative costs, lab our hours or other quantities plotted against time”. The name derives from the S-like shape of the curve, flatter at the beginning and end and steeper in the middle, because this is the way most of the projects look like.

The S curve can be considered as an indicator and it's used for many applications related to project management such as: target, baseline, cost, time etc. That's why there is a variety of S Curves such as:

- Cost versus Time S Curve ;( appropriate for projects that contain labour and non-labour tasks).
- Target S Curve;(This S Curve reflects the ideal progress of the project if all tasks are completed as currently scheduled)
- Value and Percentage S Curves;(Percentage S Curves are useful for calculating the project's actual percentage complete)
- Actual S Curve;(This S Curve reflects the actual progress of the project to date)

In order to be able to generate a S Curve, A Baseline and Production Schedule are necessary because they contain important information for each task: -the Baseline - contains information about Actual Start date and finish date.

- The Baseline - can also contain information about Man Hours and costs.
- The Production Schedule contains information about the actual percentage complete.

There is some software scheduling packages that generate automatically S Curves. For example MS Project does not have this possibility so a third party software application is needed to process the Baseline and Production Schedule data and generate the needed S Curve.( for example S Curve Generator that integrates with MS Excel to generate S Curves).


The Program (or Project) Evaluation and Review Technique, commonly abbreviated PERT, is a model for project management designed to analyze and represent the tasks involved in completing a given project.

PERT is a method to analyze the involved tasks in completing a given project, especially the time needed to complete each task, and identifying the minimum time needed to complete the total project.

PERT was developed primarily to simplify the planning and scheduling of large and complex projects. It was able to incorporate uncertainty by making it possible to schedule a project while not knowing precisely the details and durations of all the activities. It is more of an event-oriented technique rather than start- and completion-oriented, and is used more in projects where time, rather than cost, is the major factor. It is applied to very large-scale, one-time, complex, non-routine infrastructure and Research and Development projects.

This project model was the first of its kind, a revival for scientific management, founded by Frederick Taylor "Taylorism" and later refined by Henry Ford "Fordism". DuPont corporation's critical path method was invented at roughly the same time as PERT.