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This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/02635579710173239. When citing the article, please cite: Chang Chung Li, Tsong Shin Sheu, Yuh Ren Wang, (1997), “Some thoughts on the evolution of quality engineering”, Industrial Management & Data Systems, Vol. 97 Iss: 4, pp. 153 - 157.

Recently, Taguchi methods have become very popular among industries worldwide. Begins by reviewing the past discussion on quality engineering from viewpoints of Taguchi himself, practitioners and academic scholars. The weakness of Taguchi’s approach in quality engineering is not in the statistical analysis aspect. Posits that, on the contrary, it provides a way of thinking that emphasizes a philosophy of freely using the methods of design of experiments to solve engineering problems. States that, in this regard, quality engineering will be further empowered via the aid of various engineering techniques. Proposes, based on these kind of thoughts, two directions for evolution of quality engineering.

This paper aims to explore pure squeeze elastohydrodynamic lubrication (EHL) motion of circular contacts with micropolar lubricants under constant load. The proposed model can reasonably calculate the pressure distributions, film thicknesses and normal squeeze velocities during the pure squeeze process.

The transient modified Reynolds equation is derived in polar coordinates using micropolar fluids theory. The finite difference method and the Gauss–Seidel iteration method are used to solve the transient modified Reynolds equation, the elasticity deformation equation, load balance equation and lubricant rheology equations simultaneously.

The simulation results reveal that the effect of the micropolar lubricant is equivalent to enhancing the lubricant viscosity. As the film thickness is enlarged, the central pressure and film thickness for micropolar lubricants are larger than those of Newtonian fluids under the same load in the elastic deformation stage. The greater the coupling parameter (N), the greater the maximum central pressure. However, the smaller the characteristic length (L), the greater the maximum central pressure. The time needed to achieve maximum central pressure increases with increasing N and L.

A numerical method for general applications was developed to investigate the effects of the micropolar lubricants at pure squeeze EHL motion of circular contacts under constant load.

The purpose of this paper is to explore the pure squeeze elastohydrodynamic lubrication motion of circular contacts with surface roughness under constant load conditions. The proposed model can reasonably calculate the effects of surface roughness on the transient pressure profiles, film shapes, and normal squeeze velocities during the pure squeeze process.

Based on Christensen's stochastic theory, the transient modified Reynolds equation is derived in polar coordinates to consider the effects of surface roughness. The finite difference method and the Gauss‐Seidel iteration method are used to solve the transient modified Reynolds equation, the elasticity deformation equation, load balance equation, and lubricant rheology equations simultaneously.

The simulation results reveal that the circular type roughness possesses storage oil capacity. Comparatively, the radial type roughness possesses leak oil capacity. Therefore, the film thickness is found with circular type roughness, followed by smooth, and then radial type roughness. In additional, the central dimensionless pressure is found with radial type roughness, followed by smooth, and then circular type roughness.

A numerical method for general applications with surface roughness was developed to investigate the pure squeeze action in an isothermal EHL spherical conjunction under constant load conditions, but without asperities contact.

This paper computationally estimates the constitutive relationships of composite materials reinforced by single walled carbon nanotubes (SWNT).

A multiscale analysis is considered. At the nanoscale level, molecular dynamics (MD) are used to predict the stiffness for an equivalent beam. A BEM solver for the elasticity problems is extended to allow the presence of inclusions and hence is used to model a RVE for the composite matrix with the equivalent nanotube beams. A genetic algorithm (GA) is developed to generate an initial population of anisotropic materials based on FEM. The GA evolves the population of properties of anisotropic materials till a material is found whose mechanical response is the same as that of the nanocomposite.

The overall process is suitable for the constitutive relationships estimation according to the verification process outlined.

The present work is limited to 2D linear problems. However, extending it to 3D non‐linear applications is straight forward.

The present technique could be used to estimate properties of NCT composites, hence practical applications such as aeroplane structures or turbine blades could be analysed using commercial finite element software. The present methodology could be used to estimate non‐mechanical properties such as the thermal and electric properties.

The present computational technique has never been presented in the literature.

The purpose of this study is to investigate the racial/ethnic differences in mobile payment use and to explore the contributing factors to the differences.

This study used the 2018 National Financial Capability Study (NFCS) dataset to examine racial/ethnic disparities in mobile payment use. Logistic regression analyses were conducted to confirm racial/ethnic differences, and Blinder–Oaxaca decomposition analyses were performed to identify which factors explain the differences among the groups.

The authors discovered that Whites use mobile payment less than Blacks, Hispanics and Asians/others. The results revealed that prior experiences with mobile financial services, including transfer, banking and budgeting applications, all play considerable roles in explaining the disparities between Whites and other racial/ethnic groups.

This is one of the few studies to examine racial/ethnic disparities in mobile payment use with a particular focus on the influence of users' past experience with technology. The results provide insights for researchers, professionals, educators and policymakers into ways to promote future use of mobile payment.