We construct optimal designs for estimating fetal malformation rate, prenatal death rate and an overall toxicity index in a toxicology study under a broad range of model assumptions. We use Weibull distributions to model these rates and assume that the number of implants depend on the dose level. We study properties of the optimal designs when the intra-litter correlation coefficient depends on...

the current investigation presents the role of gooseberry (phyllanthus acidus) seeds as an effective biosorbent for remediating chromium (vi)), a toxic heavy metal pollutant commonly found in effluents from tanneries and relevant industries. biosorption was affected by ph, temperature and initial metal concentration. furthermore, there is a need to understand the holistic effect of all variable...

In this paper optimal experimental designs for inverse quadratic regression models are determined. We consider two different parameterizations of the model and investigate local optimal designs with respect to the c-, Dand Ecriteria, which reflect various aspects of the precision of the maximum likelihood estimator for the parameters in inverse quadratic regression models. In particular it is d...

Use of efficient methods of weed control with as regards environmental sustainability as well as increased crop yield and also weed resistance to herbicides is essential. In order to, an experiment was conducted in 2012 in the Damavand jaban in Iran. Experiment treatments were compared in a split plot design by a randomized completely block design with 3 replication. The used variety of maize w...

carbon nanotube, a new structure of carbon element, is composed of graphene sheets rolled into closed concentric cylinders with diameter of the order of nanometers and length of micrometers. liquid arc discharge was used for fabrication of carbon nanotubes, and subsequently a modified acid treatment method applied for purification stage. a statistical design of experimental (doe) (taguchi metho...

We construct optimal designs for estimating fetal malformation rate, prenatal death rate and an overall toxicity index in a toxicology study under a broad range of model assumptions. We use Weibull distributions to model these rates and assume that the number of implants depend on the dose level. We study properties of the optimal designs when the intra-litter correlation coefficient depends on...

Denitrification bioreactors for nitrate removal in agricultural drainage have recently gained attention for their low cost and effectiveness. While research continues to investigate the optimal sizing of these systems, little work has been done on the optimal design geometry (Length to width ratio and cross sectional shape). To address this lack, pilot-scale (1/10th scale) work performed in Iow...

The theory of optimal design experiments has been traditionally developed on an Euclidean space. In this paper, new theoretical results and algorithm for finding the experiment located a Riemannian manifold are provided. It is shown that analogously to in spaces, D-optimal G-optimal designs equivalent manifolds, we provide lower bound maximum prediction variance response evaluated over manifold...