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The purpose of this paper is to simulate in the time domain three‐dimensional electrical, thermal, mechanical coupled contact problems arising in electric resistance welding (ERW) processes.

A three‐dimensional multiphysical numerical model for analyzing contact problems is proposed. Electrical and thermal field equations in bulk domains are discretized with the cell method (CM). Welding resistance at contact interfaces is described locally by synthetic statistic parameters and contacting domains are matched together by a non‐overlapping domain decomposition method. Contact pressure distribution is resolved by a finite‐element procedure. The model is validated with 3D FEM software package.

The semi‐analytical model describing the electric and thermal resistances at contact interfaces can be easily embedded in CM formulations, where problem variables are expressed directly in integral form. Compatibility conditions between contact members are enforced by a domain decomposition approach. System conditioning and computing time are improved by a solution strategy based on the Schur complement method.

The electrical‐thermal analysis is not coupled strongly with the mechanical analysis and contact pressure distribution is assumed to be not depending on thermal stresses, which can be considerable near the contact area where localized joule heating occurs.

Resistance welding processes involve mechanical, electrical, and thermal non‐linear coupled effects that cannot be simulated by standard commercial software packages. The proposed numerical model can be used instead for designing and optimizing ERW processes.

The paper shows that numerical modeling of ERW processes requires a careful prediction of the localized joule heating occurring at the electrode‐material interface. This effect is reconstructed by the proposed approach simulating coupled electrical, thermal, and mechanical effects on different spatial scales.

To propose a novel 3D hybrid approach, based on a discrete formulation of Maxwell equations (the cell method – CM), suitable for solving eddy current problems in unbounded domains.

Field equations for magnetodynamics are expressed directly in algebraic form thanks to the CM. The eddy current problem inside bulk conductors is formulated in terms of discrete modified vector potential, whereas magnetic scalar potential is used in order to model the free space. The CM is coupled to the boundary element method by using a surface boundary operator, which maps the surface magnetic fluxes to the surface magnetic scalar potentials. This leads to a unique set of linear equations to be solved in terms of discrete potentials. The eddy currents in bulk conductors are then obtained from discrete potentials.

It is shown that formulation of hybrid approaches can be simplified by expressing field equations directly in algebraic form without need of weighted residual techniques. An original strategy, based on Green's formula for the magnetic scalar potential, is proposed in order to couple conducting parts to the exterior domain.

Conducting bodies with multiply connected parts cannot be modelled by the proposed approach, since it is based on the magnetic scalar potential. The resulting global matrix is partially dense and non‐symmetric; therefore, standard iterative solvers such as GMRES have to be used.

The proposed approach can be suitably used for analyzing eddy current problems involving models with high degree of complexity, large air domains and moving parts. These are typical of induction heating processes.

This paper proposes a new 3D hybrid approach, based on a discrete formulation of Maxwell equations. A novel coupling strategy relying on integral electromagnetic variables, i.e. magnetic fluxes and magnetic scalar potentials, is devised in order to solve uniquely for eddy currents inside conducting bodies.

This study aims to unveil within the current academic literature the principal directions in the ethnic entrepreneurship and small business marketing research context.

An automated literature analysis procedure was undertaken, attempting to cover all literature published on the subject since 1962. A total of 188 articles were analysed using text mining and topic modelling.

The results show a lack of framing of ethnic entrepreneurship literature outside the narrower scope of migration. Some core themes were found (e.g. network, diversity) around which several other themes orbit, including both related issues to the ethnic factor (e.g. barriers and minorities) and managerial issues (e.g. marketing and production).

Ethnic minority business and small business marketing research has seen a growing number of publications. However, a careful review of existing work is missing.

This study aims to identify the impact of restaurant pandemic mitigation measures on perceived service quality.

A total of 15,251 reviews were collected from 300 TripAdvisor Lisbon restaurant Web pages between March 2020 and December 2021, when Covid-19 contingency measures were in place. Grounded on the online reviews, a word frequency matrix was created and used as input on partial least squares–structural equation modeling to test the proposed hypotheses.

The results suggest that precaution measures, such as the Vaccination Certificate, negative tests and restaurant layout configuration, positively influenced perceived service quality and consumer satisfaction, moderated by consumers’ beliefs.

This study provides relevant information for restaurant managers, which will help them implement strategies to guarantee service quality, consumer satisfaction and revisit intentions in future pandemic scenarios.

This paper aims to propose a fast and accurate simulation of large-scale induction heating problems by using nonlinear reduced-order models.

A projection space for model order reduction (MOR) is quickly generated from the first kernels of Volterra’s series to the problem solution. The nonlinear reduced model can be solved with time-harmonic phasor approximation, as the nonlinear quadratic structure of the full problem is preserved by the projection.

The solution of induction heating problems is still computationally expensive, even with a time-harmonic eddy current approximation. Numerical results show that the construction of the nonlinear reduced model has a computational cost which is orders of magnitude smaller than that required for the solution of the full problem.

Only linear magnetic materials are considered in the present formulation.

The proposed MOR approach is suitable for the solution of industrial problems with a computing time which is orders of magnitude smaller than that required for the full unreduced problem, solved by traditional discretization methods such as finite element method.

The most common technique for MOR is the proper orthogonal decomposition. It requires solving the full nonlinear problem several times. The present MOR approach can be built directly at a negligible computational cost instead. From the reduced model, magnetic and temperature fields can be accurately reconstructed in whole time and space domains.

The purpose of this paper is to simulate passive proton exchange membrane fuel cells (PEMFCs) for portable electronic devices by means of a non‐linear lumped circuit based on electrical, mass transfer and electro‐kinetic equations.

Electrical, mass transfer and electro‐kinetic equations are combined in order to derive a non‐linear lumped circuit. The dynamic circuit model is tested in realistic operating conditions.

An original equivalent circuit model for simulating the transient behavior of passive PEMFCs is proposed. The PEMFC is represented as a non‐linear equivalent circuit with controlled lumped parameters depending on pressure, temperature, hydration, and system capacity.

Lumped parameters are synthesized assuming a one‐dimensional fuel cell model since layer thicknesses are much smaller than other dimensions. Heat generation and transfer are not modeled even though lumped parameters depend on temperature.

The proposed circuit model can be implemented directly in circuit simulators for designing power management units needed to interface small‐passive PEMFCs and portable electronics such as PDAs, laptops, or mobile phones.

The fuel cell is represented as a non‐linear controlled generator whose parameters are derived directly from multiphysics equations rather than empirical relationships. The dynamic behaviour of PEMFCs can be simulated on completely different times scales, i.e. during transients or during the discharge phase.

Overall, there is a lack of research using online reviews as a proxy of customer experience when addressing the study of tourism in island destinations.

The current investigation aims to fill this gap by focussing on an African small island developing states, i.e. Cape Verde. This paper reports of tourist reviews extracted from TripAdvisor from “two islands of the senses” as coined by this archipelago’s national tourism organization, specifically Santo Antão and Fogo islands. The data analysis was performed through Leximancer software to generate concepts out of words, followed by themes.

The present research focussed on experiences in island tourism to identify their main dimensions based on visitors’ narratives in online reviews. The obtained results are of potential value to the literature by contributing to a better understanding of tourist experience in the context of tourism in islands in an understudied country, Cape Verde.

Results are presented and object of discussion vis-à-vis scientific literature and conclusions put forward in this journal paper.

This paper investigates the links between statistical discrimination, mobility, tenure, and wage profiles in the early career of workers. The model assumes that female workers’ productivity is noisier and that the noise/signal ratio tapers off more rapidly for male workers. These two assumptions yield numerous theoretical predictions pertaining to gender wage gaps. These predictions are tested using data from the 1979 cohort of the National Longitudinal Survey of Youth. As predicted, we find that men and women have the same wage at the start of their career, but that female wages grow at a slower rate thus generating a gender wage gap.

In this chapter, the authors explore collective entrepreneurship through the lens of how public entrepreneurship boosts collective action towards a common good. The role of public entrepreneurs and the collaborative nature of innovation community members evidence a collective action that pursues a socio-political change. Through a case study contextualized during the COVID-19 pandemic crisis in Spain, the authors explore how a public entrepreneur triggered a collective action that led to the creation of the innovation community: The Coronavirus makers. This collaborative network groups more than 20,000 researchers, developers, and engineers. They altruistically put their knowledge and resources at the service of the community to provide solutions for one of the healthcare system’s main problems at that time – the shortage of medical supplies to cope with the increasing number of COVID-19 cases. The collective action of the Coronavirus makers has impacted the health and wellbeing fields, the community and the values that should define social change and allow the construction of a more open, equitable and sustainable society. Potentially, our findings confirm that collective entrepreneurship derives from a function of collective action.

This study consolidates insights on the role of virtual reality (VR) and augmented reality (AR) in tourism engagement (TE). In addition, it suggests new directions for research in tourism and hospitality.

A hybrid integrative review was used with bibliometric and theory-context-characteristics-method framework analyses of 236 peer-reviewed journal articles.

Computer science journals dominate TE in VR/AR research. Emotional and immersive attributes of VR/AR sustain TE. Exploring cultural theories can enrich TE perspectives in the context of VR/AR. This study offers fruitful directions by exploring virtual technology’s role in sustaining cultural heritage and studying TE intentions and perceptions on VR/AR tourism mobile applications.

To the best of the authors’ knowledge, this is the first study that uncovers the structure and intellectual rationale of existent research.

本研究整合了关于虚拟现实（VR）和增强现实（AR）在旅游参与（TE）中的作用的见解。此外, 本研究为旅游和酒店业的研究提供了新的方向。

本研究使用文献计量学和理论-背景-特征-方法（TCCM）框架分析, 采用混合综合审查方法, 分析了236篇同行评审的期刊文章

计算机科学期刊在VR/AR研究中主导了TE领域。VR/AR的情感和沉浸属性支持了TE。在VR/AR的背景下, 探索文化理论可以丰富TE的视角。本研究通过探讨虚拟技术在保护文化遗产方面的作用, 以及研究VR/AR旅游移动应用中的TE意图和感知, 提供了有益的研究方向。

这是第一项揭示现有研究结构和知识理论基础的研究。