When an orthogonal array is projected on a small number of factors, as is done in screening experiments, the question of interest is the structure of the projected design, by which we mean its decomposition in terms of smaller arrays of the same strength. In this paper we investigate the decomposition of arrays of strength t having t + 1 factors. The decomposition problem is well-understood for...

Some inequalities for the lower bound of the number of constraints in an orthogonal array of strength two are derived. A method of constructing balanced incomplete block designs is given which depends upon the existence of two such designs with the same block size. A large number of these designs with k c 4,5 and ~l are also given. Qualified requestors may obtain copies of this report from the ...

The orthogonal array design has been used to determine the optimum conditions for gold recovery from Zarshuran refractory gold sulfide ore (Iran) by direct cyanidation and roasting-cyanidation. The Taguchi method was used as the experimental design to determine the optimum conditions of dissolution behavior of gold with cyanidation and roasting-cyanidation from Zarshuran refractory gold ore . T...

In this paper, we show that the projection of a regular orthogonal array of strength t onto more than t factors consists of replicates of either a fractional factorial or a full factorial design of strength t, depending on the number of factors retained in the projection.

consider search designs for searching one nonzero 2- or 3-factor interaction under the search linear model. in the noisy case, search probability is given by shirakura et al. (ann. statist. 24(6) (1996) 2560). in this paper some new properties of the searching probability are presented. new properties of the search probability enable us to compare designs, which depend on an unknown parameter ?...

We propose an approach to constructing a new type of design, a sliced space-filling design, intended for computer experiments with qualitative and quantitative factors. The approach starts with constructing a Latin hypercube design based on a special orthogonal array for the quantitative factors and then partitions the design into groups corresponding to different level combinations of the qual...