Theory of Constraints Handbook - James Cox Iii [597]
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Lean
Lean—A holistic and sustainable management philosophy built on minimizing resources used in organization activities and simplifying processes by eliminating non-value-adding steps with a focus on flow of parts and products from entry into the system to receipt by customers. Multi-skilled workers utilize lean methods to reduce time, blockages, and cost.
Value stream mapping—The process of diagramming and analyzing the creation, production, and delivery of a good or service through the value chain to the customer. For a service, the value stream consists of suppliers, support personnel, technology, and the provider and payment process.
Mistake proofing—Error prevention. The study of causes of errors with the focus on the elimination of the cause.
Standard workflow methods—The simplification and standardization of activities, processes, and procedures to increase workflow through an organization. A focus of these methods is the elimination of non-value-added activities.
Five S’s—A set of processes (originally part of Lean) designed to clean up and make a work environment safe, efficient, and effective. These processes include: sort, simplify, scrub, standardize, and sustain.
Total preventive/productive maintenance—Worker initiated maintenance activities focused on eliminating equipment breakdowns and the continuing improvement of the equipment.
Total kit—The building of a package of items needed to support a stage in the provider-patient process. For example, having all the necessary items in place so that the doctor is able to respond to the next patient’s needs without having to wait or search for any items (patient records, patient plan, supplies, instruments, assistant, etc.).
Setup time reduction—The removal of non-value-added time from the setup process.
Six Sigma
Six Sigma—A methodology to decrease process variation and improve product quality and includes the DMAIC and DFSS methodologies.
Design-Measure-Analyze-Improve-Control (DMAIC) process—A Six Sigma improvement methodology based on five interrelated steps: (1) design is the determination of the problem; (2) measure current performance versus the desired performance and causes of performance problems; (3) analysis to identify the core problem; (4) improve by identifying and implementing the problem solution; and (5) control by executing, monitoring, and making corrections to the new process.
Design for Six Sigma (DFSS)—A defect-prevention methodology. The process design of the valueadded activities from product and process design to customer use capturing the voice of customer (VOC) and translating customer needs into quantifiable customer requirements with the objective of making processes and products robust to eliminate defects.
Quality functional deployment—A methodology to ensure that the voice of the customer (customer requirements) is clearly defined and incorporated as a customer need into the service design of the business (functional requirement). For example, a customer may not want to wait more than 10 minutes after filling out paperwork to being shown to the examining room.
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TABLE 31-1 Lean and Six Sigma Tools with Brief Definitions
Lean tools,5 when applied to strategically important areas identified through TOC processes, cause breakthrough results. However, the focusing power of TOC via BM and the TP are needed to focus attention where it counts. In the current Total Quality Management (TQM) movement, its tools are applied everywhere without the focus of TOC to spotlight where action will do the most good. Disappointing improvements without significant improvements in Throughput or in customer satisfaction is the result. These unfocused improvement