Case Studies and White Papers

Published: February 2013
Author: Sara Black

Resin manufacturer Interplastic Corp. Thermoset Resins Div. (St. Paul, Minn.), a major gel coat producer, recently developed a new gel coat with the aid of Design-Expert design of experiments software from Stat-Ease Inc.

Publication: Composites Technology

Optimal Experimental Design with R

Published: May 2012
Authors: Mark Anderson, Wayne Adams

BOOK REVIEW: This book provides guidance on the construction of experiments, including sample size calculations, hypothesis testing, and confidence estimation.

Publication: Technometrics

Published: May 2012
Author: Wilson Collier

Researchers at Codexis Laboratories Singapore performed a full-factorial designed experiment with 20 runs to determine the impact of four independent variables on product selectivity during a silylation reaction. The result was a process that delivered 95% selectivity along with an 88% yield.

Publication: Pharmaceutical Manufacturing

Framing a QbD Design Space with Tolerance Intervals

Published: May 2012
Author: Mark Anderson

Given the push for Quality by Design (QbD) by FDA and drug agencies worldwide, statistical methods are becoming increasingly vital for pharmaceutical manufacturers. Response surface methods for DOE provide powerful tools to manage the impact of multiple factors and their interactions.

Publication: Pharma QbD

Published: March 2012
Authors: Zhou Jiang, Kurt Droms, Zhaohui Geng, Susan Casnocha, Zhihua Xiao, Steve Gorfien, Scott Jacobia

Researchers aiming to upgrade a fed-batch process observed that basal and feed media have interrelated impacts on process outcomes (a pairing effect). They did a DOE enabled by Design-Expert software for fed-batch cell culture process optimization.

Publication: BioProcess International

Published: March 2012
Authors: Patrick Whitcomb, Mark Anderson

Statistical methods are becoming increasingly vital for pharmaceutical manufacturers. Design of experiments (DOE) is a primary tool for determining the relationship between the factors that have an effect on a process and the response of that process.

Publication: Stat-Ease, Inc.

Published: January 2012
Authors: David Stiles, Zhiming Zhang, Pei Ge, Brian Nelson, Richard Grondin, Yi Ai, Peter Hardy, Peter Nelson, Andrei Guzaev, Mark Butt, Klaus Charisse, Verbena Kosovrasti, Lubomir Tchangov, Michael Meys, Martin Maier, Lubomir Nechev, Muthiah Manoharan, William Kaemmerer, Douglas Gwost, Gregory Stewart, Don Gash, Dinah Sah

This article explores a therapeutic strategy for treating Huntington's disease.

Publication: Pharma Qbd

Design of Experiments for Non-Manufacturing Processes: Benefits, Challenges, and Some Examples

Published: November 2011
Authors: Mark Anderson, Jiju Antony, Shirley Coleman, Rachel Johnson, Douglas Montgomery

Design of experiments (DOE) is a powerful technique for process optimization that has been widely deployed in almost all types of manufacturing processes and is used extensively in product process design and development. There have not been as many efforts to apply powerful quality improvement techniques such as DOE to improve non-manufacturing processes. Factor levels often involve changing the way people work and so have to be handled carefully. It is even more important to get everyone working as a team. This paper explores the benefits and challenges in the application of DOE in non-manufacturing arena.

Publication: Journal of Engineering Manufacture

Published: November 2011
Authors: Jin Yeong Shin, Purev Delgerzaya, Yong Bin Lim, Jin-Byung Park, Kwang-Ok Kim

This study was conducted to examine the chemical and sensory characteristics of fermented worts and consumer acceptability according to added flavorings. The worts were fermented by yeast (Saccharomyces cerevisiae) following fermentation by lactic acid bacteria (Leuconostoc citreum) at different aeration conditions. Chemical and sensory descriptive analyses were conducted to examine the effects of the fermentation conditions. The consumer acceptability of the worts with added flavorings was also examined. Organic acids, functional sugars, and ethanol were produced by L. citreum and S. cerevisiae, respectively. Ethanol concentrations ranged from 10 to 25 g/L depending on the fermentation conditions. The sensory characteristics of the fermented worts were clearly differentiated by the fermentation conditions. Yeast fermentation resulted in high intensities for certain sensory attributes such as ‘alcohol’, ‘fermented barley’, ‘fermented white grape’, and ‘grassy’. Consumer acceptability changed with different levels of sugar and lemon flavoring, and the optimum levels were determined as 14.08% sugar and 0.98% lemon flavoring. Under these conditions, it was shown that a relatively acceptable fermented wort beverage containing functional materials can be produced.

Publication: Food Science & Biotechnology

Design-Expert Diagnostics Saves Experiment (and Post-Grad Student)

Published: August 2011
Author: Paul Mullenix

See how the diagnostic features of Design-Expert enabled a post-doctoral researcher to achieve a valid analysis, and graduate on time. Lesson learned: Checking diagnostics just might save your next experiment.