Taguchi designs

Tag open-cup test Taguchi designs Taguchi gas sensors Taiguie acid Tailings... 

Ealey, L.A. (1988), Quality by design. Taguchi Methods and U.S. industry. Dearborn, MI ASI Press. 

The DX6 program generates most of the symmetric designs, Taguchi orthogonal designs, and exact D-optimal designs for process, mixture, and process+mixture combined spaces. DX6 can also handle constrained mixtures. It can also produce the respective two- and three-dimensional-contour Descartes and mixture plots. There is considerable flexibility provided in model construction and their modification. 

The improvement of the quality of a design is seen as the primary need of industry, but to facilitate this we need appropriate methods for predicting quality and evaluating the long-term quality of an engineer s design (Morup, 1993 Russell and Taylor, 1995 Shah, 1998 Taguchi et al., 1989). However, there is relatively little work... 

Robust design is the design of a product or process that results in functionally acceptable products within economic tolerances (Taguchi et al., 1989). 

Pitts, G. and Lewis, S. M. 1993 Design Modelling the Taguchi Way. Professional Engineering, April, 32-33. 

Taguchi uses fractional factorial designs to determine the first-order effects of both the control factors and the noise factors, but he separates the factors and the designs into an inner array (involving the control factors only) and an outer array (involving the noise factors only). The concept is shown geometrically in Figure 14.8 for three control factors and three noise factors. 

Kackar, R.N. (1985), Off-Line Quality Control, Parameter Design, and the Taguchi Method, J. Qual. Technol, 17, 176-209. 

Ross, P.J. (1988), Taguchi Techniques for Quality Engineering Loss Function, Orthogonal Experiments, Parameter and Tolerance Design, McGraw-Hill Book Company, New York, NY. 

Taguchi, G. (1986), Introduction to Quality Engineering Designing Quality into Products and Processes, Asian Productivity Organization, Tokyo. Available in North America from UNIPUB, Kraus International Publications, White Plains, NY. 

Quality Engineering by Design - The Taguchi Approach The Center fcff Quality and Applied Statistics, Rochester Institute of Technology Rochester, NY, 1989. 

Barker, T. B. Engineering Quality By Design - Interpreting the Taguchi Approach-, Marcel Dekker New York, NY, 1990 p 20. 

The Taguchi method consists of a philosophy of quality, experimental design methods to build in robustness and methods to analyze data obtained from the experiments. All these topics are treated in text books [10-13]. 

In recent years much attention has been focused on the impact of the use of statistics, and in particular experimental design, to improve the quality of products and processes. An important component of the quality of a product is its robustness or stability in the presence of what Taguchi has called noise variables. 

One of the rationales for the noise arrays and cross-product designs advocated by Taguchi and discussed in Section 2.1 is to deliberately... 

Thus, the experimental designs advocated by Taguchi can require a prohibitively large number of runs. 

Taguchi s approach of using a separate design and environmental array might result in a nine run fractional factorial design for the design... 

Thus, not only will this design estimate all of the linear and quadratic terms and interactions between the design and the environmental variables, but it will also estimate all of the two-factor interactions among the design variables and among the environmental variables. It will accomplish this in only (26 + runs, compared with the 81 runs for the Taguchi design that yields less information. 

As another example of the reduction in the number of runs, consider an experiment to investigate three design and four environmental variables, all at three levels. A Taguchi crossed array might use a 3 fractional factorial design for the design array and a 3 fractional factorial design... 

Note that even if the environmental variables are at two levels so that a 2 fractional factorial design can be run for the Taguchi environmental array, the complete crossed design has 9x8 = 72 runs, still more than the Box-Behnken design of Table 2.12, while providing estimates of fewer coefficients of the second-order model. 

Having considered the advantages of designing an experiment with a combined set of design and environmental variables, as opposed to Taguchi s crossed arrays, this section will consider the analysis of such experiments. 

Taguchi) with no replication would require not only 72 tablet batches, but also 72 operations of the chamber. It is clear, therefore that this experimental arrangement can be considerably easier to run than the completely randomized cross-product design. 

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