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When considering the one dimensional semiconductor device equations, the condition number turns out to be so large that a numeric solution of the equation is meaningless. Applying singular perturbation methods to the linearized model the solution can be separated into two parts: One, which is very sensitive to perturbations, and one, which is robust against perturbations of the equations.

In this paper we carry out a conditioning analysis for the steady state semiconductor device problem. We consider various quasilinearizations as well as Gummel‐type iterations and obtain stability bounds which may allow ill‐conditioning in general. These bounds are exponential in the potential variation, and are sharp e.g. for a thyristor. But for devices where each smooth subdomain has an Ohmic contact, e.g. a pn‐diode, moderate bounds guaranteeing well‐conditioning are obtained. Moreover, the analysis suggests how various row and column scalings should be applied in order for the measured condition numbers of the linearized discrete problem to correspond more realistically to the true loss of significant digits in the calculations.

The Van Roosbroeck semiconductor device equations are put into useful analogy with the Arrhenius equations of combustion theory. Both, when written in appropriate variables, enjoy (suffer) exponential nonlinearities. Here, we present this analogy in rather simple terms. It is proposed that this analogy be further developed.

Uses a streamline‐diffusion finite element method, specially designed for semiconductor device models, to simulate silicon MESFET devices in two space dimensions. Considers the full hydrodynamic model, a simplified hydrodynamic model and drift‐diffusion model. The method, which reduces to the well‐known Scharfetter‐Gummel discretization for the conventional drift‐diffusion model in one space dimension, proves to be a robust numerical tool. It performs well also when the solution has layers of rapid variation across junctions which are not aligned with mesh lines. Makes comparisons for the different models. Finds a qualitative discrepancy between the solutions of the hydrodynamic model and the drift diffusion model. Observes a small difference, however, between the full and simplified hydrodynamic models.

The improvement of the hydrogen evolution reaction (HER) performance requires more efficient and inexpensive electrocatalysts. The purpose of this study is to prepare Ni-W and Ni-W-P thin films using the electrodeposition technique using a pulse current and investigate their behaviors toward HER in an acidic solution.

The aim is to prepare Ni-W and Ni-W-P films by the electrodeposition technique using a pulse current and estimate their performance for the HER. The surface morphologies and chemical compositions of the deposited films were assessed using scanning electron microscopy, energy-dispersive X-ray analysis and X-ray diffraction. Linear sweep voltammetry, chronoamperometry, Tafel plots and electrochemical impedance spectroscopy were used to evaluate the prepared electrodes toward the hydrogen evolution process.

The main conclusion is that the surface morphology of Ni–W deposited film is a crystalline structure, while that of Ni-W-P deposit is an amorphous structure. HER activity on Ni-W electrodes increases with decreasing the Wt.% of W to 7.83 Wt.% in the prepared electrodes. In addition, the presence of P enhances HER activity, which increases with increasing the Wt.% of P in the prepared Ni-W-P electrodes. Both Ni-W (7.83 Wt.% W) and Ni-W-P (20.34 Wt.% P), which have been prepared at 8 A dm⁻² display the best performance toward HER compared to the other prepared electrodes. They exhibit high catalytic activities toward HER, which is evidenced by high hydrogen evolution current density values of 9.52 and 33.98 mA cm⁻², low onset potentials of −0.73 and −0.63 V, low Tafel slopes of −125 mV/dec, high exchange current densities of 0.058 and 0.20 mA cm⁻², low charge transfer resistances (Rct) of 226.28 and 75.8 ohm·cm² for Ni-W (7.83  Wt.% W) and Ni-W-P (20.34  Wt.% P), respectively; moreover, they exhibited considerable stabilities too.

The results presented in this work are an insight into understanding the performance of the prepared Cu electrodes coated by Ni-W and Ni-W-P films toward HER. In this work, a consistent assessment of the results achieved on laboratory scale has been conducted.

This paper aims to present historical examples of collaborations between brand strategists and artists; provide an extensive, structured overview of existing published research on such collaborations and their effects; present seven papers comprising this special issue; and discuss ideas for further research into brand–art collaboration.

This is an editorial based mainly on an extensive and broad literature review.

First, this editorial underpins the relevance of brand–art collaboration in the past and present by reference to real examples. Second, it structures the diverse literature into four key aspects of the topic: inspiration, insights, identity and image. Third, it provides a glimpse of the seven papers selected for this special issue. Fourth and finally, it identifies a total of 16 avenues for further research, on four levels (artist, brand owner, consumer and cooperation process).

This editorial and the entire special issue together represent the first anthology on the topic of the interface between brand management and arts. The collection and classification of the existing literature, the formulation of ideas for future research and the content of the seven papers are collectively excellent starting springboards for new and fresh brand research projects.