My PhD Blog

LSS = Lean Six Sigma ; EE = Enterprise Engineering

In the line of reasoning of the business problem we noted that the professionals in both disciplines work isolated from each other. Combine this with the fact that both have their own fundamental theories we find ourselves in a situation of segregated concepts. So an useful concept within LSS does not necessarily lead to a meaningful concept for EE. So if we strive towards a merger of Lean Six Sigma and Enterprise Engineering we need a fundamental research to explore the conceptual areas of segregation.

Overseeing fundamental research we observed a research pattern. Researchers explore in many cases the meaning of a concept by placing them in a meta-model. This creates a situation and opportunity to reason its meaning from the meta model perspective and its position within. For example if a concept is positioned in an upper ontology we are capable to reason its meaning in the realm of the philosophical existence. As enterprise ontology is the cornerstone for enterprise engineering the concepts within are scientifically well defined.

Lean Six Sigma is different. Recently in 2007, Henk de Koning a researcher of IBIS UVA (section 2.1) delivered a scientifically grounding for LSS based upon a rational reconstruction (Koning, 2007). In this report Six Sigma is seen as quality improvement strategy (Koning, 2007 p. 21) which is in line with our introduction of LSS in section 2.2.3. The statement implicit expresses the importance of quality for LSS therefore a definition of Quality was reconstructed from publications of thought leaders.

Definitions: (Koning, 2007 p. 22)

Product Quality: product quality refers to product characteristics and the extent to which they meet customer (meaning: end-user) demands. Product characteristics that together make up product quality are: performance, features, reliability, conformance, durability, serviceability, aesthetics and perceived quality.

Process Quality: process quality reflects the demands of internal customers, and comes down to effectiveness (the extent to which a process provides required features) and efficiency (being effective at low cost). Dimensions of process quality include defect rates, but as well cycle time, yield and production costs not related to defects.

Understanding these definitions from a semiotic triangle perspective (Dietz, 2006 pp. 36, fig 4.1) these definitions are concepts, reconstructed from the mental pictures of LSS publicists. Within these definitions we can identify process and product characteristics which are other concepts from which the six sigma level of quality is reasoned. For reasoning purpose we marked them red in the next figure.

Figure 11 Rational reconstruction of Six Sigma’s business context.

These process characteristics are important concepts because they bind the LSS concerns with the business transaction oriented way of modeling of DEMO. If we strive towards an integrated methodology we need to understand their ontology and their relationship with the enterprise ontology. In practical terms, concepts like ‘Yield’, ‘cycle times’, ‘defects rates’ need to be studied in the context of the ontological parallelogram (Dietz, 2006 pp. 39, fig 4.2).

Currently there is a lack of knowledge how these process characteristics fit into the enterprise  ontology . As result of this, it is not only difficult to strive further to one integrated methodology but what is more severe is our missing understanding of quality (incl process characteristics) in the realm of enterprise ontology.

Dietz, Jan. 2006. Enterprise Ontology, ISBN: 3540291695. Delft : Springer Verlag, 2006.

Koning, Henk de. 2007. Scientific Grounding of Lean Six Sigma’s Methodology. Amsterdam : UVA, 2007. 978-90-6464-176-3.