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The purpose of this paper is to present an effective optimization strategy applied in a physical structure optimization of a semiconductor power metal oxide semiconductor field‐effect transistor (MOSFET), with an expensive integration constraint computation.

In order to deal with inaccuracy due to inevitable numerical errors in the objective function calculation (the power losses of the power MOSFET) and in the constraint computation, the paper proposes to use the progressive quadratic response surface method (PQRSM).

The paper focuses on four aspects: the inevitable numerical errors in the power loss and the integration constraint computation; the response surface approximation (RSA) method; the PQRSM principle; and finally the comparisons of several optimization methods applied on this application problem.

An original optimization method, PQRSM, is proposed for reducing the oscillation problem of a semi‐analytical model. The optimization results of PQRSM have been compared with the evolution strategy (ES) algorithm, with similar results but faster computation.

Scientists and engineers have been solving Poisson’s equation in PN junctions following two approaches: analytical solving or numerical methods. Although several efforts have been accomplished to offer accurate and fast analyses of the electric field distribution as a function of voltage bias and doping profiles, so far none achieved an analytic or semi-analytic solution to describe neither a double diffused PN junction nor a general case for any doping profile. The paper aims to discuss these issues.

In this work, a double Gaussian doping distribution is first considered. However, such a doping profile leads to an implicit problem where Poisson’s equation cannot be solved analytically. A method is introduced and successfully applied, and compared to a finite element analysis. The approach is then generalized, where any doping profile can be considered. 2D and 3D extensions are also presented, when symmetries occur for the doping profile.

These results and the approach here presented offer an efficient and accurate alternative to numerical methods for the modeling and simulation of mathematical equations arising in physics of semiconductor devices.

A general 3D extension in the case where no symmetry exists can be considered for further developments.

The paper strongly simplify and ease the optimization and design of any PN junction.

This paper provides a novel method for electric field distribution analysis.

The purpose of this paper is to trace the evolution of paternalism as a long-term component of a management control system (MCS) in a multi-national business enterprise.

The authors used a historical methodology involving the collection and evaluation of both primary and secondary data. Annual reports of Michelin (2009–2021) were also analysed to trace the evolution of the MCS towards corporate social responsibility (CSR).

This research traces the evolution of Michelin's Paternalistic MCS from “Traditional Paternalism” to “Welfare Paternalism”, “Managerial Paternalism” and “Libertarian Paternalism” thereby leading the way to CSR. The findings indicate that the evolution of the MCS revealed “Managerial Paternalism” as a specific type of paternalism and an important component of the “Personnel and Cultural Controls” (Merchant and Van der Stede, 2018, p. 95) at Michelin.

Many multi-national companies began as family-owned and controlled firms (e.g. Ford, Toyota, Fiat, Renault, Tata) and they often employed paternalistic MCSs during their early development (Newby, 1977; Perrot, 1979; Colli, 2003). Such MCSs have been seen as being anachronistic and are often abandoned as the family-owned enterprise grows into a multi-national company (Casson and Cox, 1993; McKinlay et al., 2010). The research challenges this assertion and demonstrates how aspects of a paternalistic MCS can survive in a multi-national business enterprise.

With respect to practical implications, this research shows that paternalism can still be a component of an MCS in a multi-national enterprise.

Using a historical approach, this research addresses a gap in the prior literature regarding the variations and persistence of paternalism in companies. In the case of Michelin, the authors investigate the evolution of its paternalistic MCS from a traditional form to an emphasis on CSR.

The purpose of this paper is to assess the Boussinesq approach for a wide range of Ra (10 × 6 to 10 × 11) in two-dimensional (square cavity) and three-dimensional (cubic cavity) problems for air- and liquid-filled domains.

The thermal behavior in “differentially heated cavities” filled with air (low and medium Rayleigh) and water (high Rayleigh) is solved using computational fluid dynamics (CFDs) (OpenFOAM) with a non-compressible (Boussinesq) and compressible approach (real water properties from the IAPWS database).

The results from the wide range of Rayleigh numbers allowed for the establishment of the limitation of the Boussinesq approach in problems where the fluid has significant density changes within the operation temperature range and especially when the dependence of density with temperature is not linear. For these cases, the symmetry behavior predicted by Boussinesq is far from the compressible results, thus inducing a transient heat imbalance and leading to a higher mean temperature.

The main limitation of the present research can be found in the shortage of experimental data for very high Rayleigh problems.

Practical implications of the current research could be use of the Boussinesq approach by carefully observing its limitations, especially for sensible problems such as the study of pressure vessels, nuclear reactors, etc.

The originality of this paper lies in addressing the limitations of the Boussinesq approach for high Rayleigh water systems. This fluid is commonly used in numerous industrial equipment. This work presents valuable conclusions about the limitations of the currently used models to carry out industrial simulations.