universally optimality for one-sided interference model

In many areas such as agriculture, forestry and medicine the interferencemodels are arised when the response of a treatment is affected by the other treatmentsin neighbor experimental plots. there are many experiments specially in agricultrethat the block size (k) is greater than the number of treatments (t) and if k > t,the universally optimal designs under the interference models are usually difficult toobtain. in circular block designs with t < k < 2t, we consider the interference modelwith left-neighbor effects such that the observations are uncorrelated. the universallyoptimal designs are obtained based on the kushner’s method.