Computer graphics processing and selective visual display system – Computer graphics processing – Graph generating
Reexamination Certificate
1999-03-18
2002-12-31
Luu, Matthew (Department: 2672)
Computer graphics processing and selective visual display system
Computer graphics processing
Graph generating
C345S960000
Reexamination Certificate
active
06501473
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to the field of project management and scheduling techniques. In particular, the present invention concerns a novel approach to Theory of Constraints (TOC) buffer graphing, tracking and the management of projects in accordance with TOC techniques.
BACKGROUND OF THE INVENTION
Various techniques have been used for the management of project scheduling. One of the techniques used to manage such project scheduling is, for example, (Program Evaluation and Review Technique (PERT) chart techniques. PERT chart techniques have been used quite extensively in the management of project scheduling. The PERT technique uses a well known critical path method.
Another technique that has been used for project scheduling and tracking is the Theory of Constraints (TOC). This technique, which is a relatively new approach, is described in detail in the book “Critical Chain,” by Eliyahu Goldratt (The North River Press, Great Barrington, Mass. 1997). Some of the key principles of the TOC include the focusing of attention on the critical chain (that chain of events and staff that most determines the delivery interval), eliminating multi-tasking of individuals when building and implementing schedules, and the managing of progress via intervals rather than dates.
In particular, TOC schedules are created by estimating 50% confidence intervals for the individual development tasks of the complete project, i.e. 50% probability of completing the individual task, and then linking them together to create an overall schedule. Because the probability for delivery of the product at completion of the 50% chain is significantly legs than 100% probability, a project buffer, PB, or safety interval, must be added at the end of the critical chain. For non-critical components that feed into the schedule, a feeding buffer, FB, is inserted at the point where the non-critical component links into the critical chain. The “padding” in the schedule, then, is located at the end of each component chain rather than distributed throughout all tasks.
One of the major drawbacks that exists with presently available TOC-based systems and methods is the inability to quickly and easily generate, update, interpret and understand buffer charts which are suitable for use by all project members in tracking progress to plan.
In particular, presently available tabular systems and methods do not allow project members, or more importantly project managers the ability to readily visually ascertain at a glance, by reference to a chart or model or graphical illustration, when buffer levels are getting too low, such that action can be taken in order to improve delivery results.
Another drawback that exists is the inability to know the actual status of each project component, and especially one that is critical (in order to apply the TOC methodology of identifying and elevating the critical chain). It is difficult, however, to determine this unless one analyzes the detailed schedule and derives the critical chain from dates cascaded by the presently known tools, such as, for example, a software product known as ProChain.
Consequently, there exists a need to quickly and easily generate and update buffer charts by using, for example, a computer system and method. In addition, there exists a need to quickly and easily visually detect when buffer levels are getting too low, so that appropriate action may be taken by project members. Furthermore, there exists a need to provide management with a simple method which may be used to determine a current critical chain.
SUMMARY OF THE INVENTION
These needs and others are met using a novel approach to Theory of Constraints (TOC) project management. In the known TOC project management approach, schedules contain buffers or “safety intervals” located at the end of non-critical task chains and at the end of the critical chains. Some consumption of these buffers is likely during development, and progress relative to plan is tracked by monitoring these buffer levels. Furthermore, acceptable buffer consumption may be modeled in a number of ways, including as a linear process over time.
The project management approach of the present invention utilizes feeding and project buffer chart construction and interpretation, and includes a graphical method to identify the effect of critical chain components on the overall project. Specifically, buffer consumption over actual project time is plotted such that one may easily and readily determine, by visual reference to the graph, when buffer consumption crosses a visually discernible minimum consumption line and/or an “alarm line” which should trigger some corrective management action.
It should be noted that this approach to TOC buffer graphing, tracking and management can be accomplished by the use of computers. For example, several software packages such as Microsoft Project, ProChain (a TOC scheduler) and Microsoft Excel (as well as various other spreadsheet programs) may be employed to automate the inventive methods and techniques disclosed herein.
REFERENCES:
patent: 5627973 (1997-05-01), Armstrong et al.
patent: 5659768 (1997-08-01), Forbes et al.
patent: 5874965 (1999-02-01), Takai et al.
patent: 5893074 (1999-04-01), Hughes et al.
patent: 5907490 (1999-05-01), Oliver
patent: 5974391 (1999-10-01), Hongawa
patent: 5993041 (1999-11-01), Toba
patent: 6008817 (1999-12-01), Gilmore
patent: 6023702 (2000-02-01), Leisten et al.
patent: 6101481 (2000-08-01), Miller
patent: 6216109 (2001-04-01), Zweben et al.
patent: 6240395 (2001-05-01), Kumashiro
patent: 6282514 (2001-08-01), Kumashiro
Andrews Michael W.
Hayes Todd R.
Loenen Ed van
Harrison Chante'
Lucent Technologies - Inc.
Luu Matthew
LandOfFree
Method and system for theory of constraints buffer graphing,... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and system for theory of constraints buffer graphing,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and system for theory of constraints buffer graphing,... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2994784