Year of Publication


Degree Name

Doctor of Philosophy (PhD)

Document Type

Doctoral Dissertation




Mechanical Engineering

First Advisor

Dr. Kozo Saito


Organizations around the world have attempted to implement the concepts of the Toyota Production System (TPS), commonly referred to as Lean, with limited sustainable success. The central principles of TPS, continuous improvement and respect for people, are grounded in the Japanese values of Monozukuri and Hitozukuri. Monozukuri deals with creating or making a product, while Hitozukuri conveys the idea of developing people through learning. In order for organizations to adopt these values they must have a system that engages employees at all levels in applying problem solving to improve their work. This research uses organizational assessments obtained from a variety of organizations implementing the lean approach using the Monozukuri and Hitozukuri values, referred to as the True Lean System (TLS).

This research uses an inductive research approach to identify and analyze factors that impact the use of problem solving within organizations implementing a TLS. First, the qualitative assessment data is studied using textual analysis to identify themes impacting TLS. This analysis identified three topics as the highest weighted themes: number of problem solving methods, standardization, and employee roles. This qualitative data is then transformed using an integrated design model to systematically code the information into quantitative numerical data. Finally, this data was analyzed statistically by logistic regression to identify the factors impacting the use of problem solving within these organizations.

The results from the logistic regression suggest that the most successful problem solving organizations have established standards for work and training employees; as well as, a single problem solving method that all employees use when identifying and implementing continuous improvement ideas. Which leads to the conclusion, in order for an organization to sustain the concepts of TPS, there must be a focus on defining clear standardized work, training, and the implementation of a single problem solving method.

Digital Object Identifier (DOI)