BACKGROUND Enzymatic hydrolysis of lactose is one of the most important biotechnological processes in the food industry, which is accomplished by enzyme β-galactosidase (β-gal, β-D-galactoside galactohydrolase, EC 3.2.1.23), trivial called lactase. Orthogonal arrays design is an appropriate option for the optimization of biotechnological processes for the production of microbial enzymes. METH...

 The use of optimal orthogonal array latin hypercube designs is proposed. Orthogonal arrays were proposed for constructing latin hypercube designs by Tang (1993). Such designs generally have better space filling properties than random latin hypercube designs. Even so, these designs do not necessarily fill the space particularly well. As a result, we consider orthogonal-array-based latin...

This paper describes the shape optimization of impeller blades for a anti-heeling bidirectional axial flow pump used in ships. In general, a bidirectional axial pump has an efficiency much lower than the classical unidirectional pump because of the symmetry of the blade type. In this paper, by focusing on a pump impeller, the shape of blades is redesigned to reach a higher efficiency in a bidir...

Examination of histological sections from flaccid and artificially erected nine-banded armadillo (Dasypus novemcinctus) penises confirms that the mammalian corpus cavernosum is the first known biological hydrostat reinforced by collagen fibers arranged at 0 degree and 90 degrees to its long axis. The morphology of this axial orthogonal fiber array affects the mechanical behavior of mammalian pe...

This paper proposes an efficient approach for optimizing the multiple quality characteristics (QCHs) in manufacturing applications on the Taguchi method using the super efficiency technique in data envelopment analysis (DEA). Each experiment in Taguchi’s orthogonal array (OA) is treated as a decision making unit (DMU) with multiple QCHs set as inputs or outputs. DMU’s efficiency is evaluated th...

Sensitivity analysis (SA) is a commonly used approach for identifying important parameters that dominate model behaviors. We use a newly developed software package, a Problem Solving environment for Uncertainty Analysis and Design Exploration (PSUADE), to evaluate the effectiveness and efficiency of ten widely used SAmethods, including seven qualitative and three quantitative ones. All SAmethod...

One of the major steps toward the industrialization of the microbial product(s) is to optimize the cultivation conditions at the large-scale bioreactor and successfully control the microbial behavior within a large scale production environment. Statistical Design of Experiment was proven to optimize a vast number of microbial processes to achieve robustness and explore possible interactions...

Acknowledgement I would especially like to express my most sincere thanks to my advisor, Professor Masayoshi Aikawa, for his invaluable guidance, advice, encouragement and support throughout the completion of my study and this thesis. I would also like to express my appreciation to the members of my thesis committee, Professor Kohei Arai, Professor Tatsuya Furukawa, Associate Professor Sumio Fu...

The structural performance of metallic components is a significant challenge especially when it comes to operating conditions in real-world applications. Friction stir additive manufacturing (FSAM) solid-state (AM) that provides controlled microstructure with homogenous grains and excellent performance. In this study, the FSAM technique was utilized fabricate lightweight laminated AA6061/AA7075...