Current Reality Tree Research Articles

Co-existence of paradigms as a manufacturing management strategy

In manufacturing management, Goldratt [1] identifies a core conflict between managing according to the cost world (CW) and the throughput world (TW) paradigms. He demonstrates that this conflict is eliminated if operations are managed solely according to the TW paradigm. A current reality tree (CRT) is created for a generic manufacturing system that reflects the chaos associated with managing according to both paradigms. Next, a future reality tree (FRT) is created to ascertain the effect of removing the policies derived from the CW paradigm in reversing the undesirable effects and eliminating the systemic chaos. Although the system is found to be stable as predicted under various simulation runs, chaos returns if the system disturbances are greater than management’s ability to deal with them. A new FRT is then created with both paradigms present and stability returns if TW-derived policies are permitted to take precedence over any corresponding CW-derived policies.

Applying the TOC thinking process in manufacturing: A case study

A case study is presented to illustrate the application of the Theory of Constraints thinking process logic tools in a manufacturing environment. The study firm performs design activities related to meeting future product requirements while concurrently meeting existing production schedules for the current design of the product. Current approaches to managing the firm's limited productive capacity do not allow for both design and production activities to occur simultaneously while meeting the customer's current product delivery schedule. Thus, despite their desire to satisfy their customer's future design requirements, management uses the majority of its production capacity to meet its customer's current product delivery schedule. This case study demonstrates how a team of employees used thinking process logic diagrams to document reality, identify a core conflict and problem, develop proposed changes to address the core problem, and create several detailed action plans to implement changes within the study organization. Initially, scenarios associated with some undesirable effects are used to understand how prevailing policies and behaviours result in less than desired production line performance. Then, a current reality tree is constructed to link the core problem or system constraint with the previously identified undesirable effects. Next, two major injections are developed to address the core problem in managing the production line as logically documented in a future reality tree. Finally, three transition trees are presented to guide the implementation of change at the study organization.