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In this paper, stochastic optimisation and risk estimation techniques are applied to the problem of hydroelectric generator design. Optimisation results from deterministic simulations can involve considerable risks due to unavoidable variations in system properties as well as environmental conditions. Therefore, stochastic simulation is used to include the effects of parameter scatter and noise effects in the computer models. This allows the evaluation of the scatter in performance and thus an assessment of reliability and quality of the simulated system.

A boundary element method in terms of the field variables is applied to three‐dimensional electromagnetic scattering problems. Especially, the influence of a dipole excited field on low conducting materials situated very close to the antenna will be discussed. We use higher order edge elements of quadilateral shape for the field approximation on curved surfaces. The tangential components of the unknown field variables are interpolated by vector element functions. The Galerkin method is implemented to obtain a set of linear equations. The applicability of the proposed edge element is investigated by the comparison of different BEM‐formulations and FEM‐results.

In this paper, a hybrid formulation for solving time harmonic eddy current problems in terms of magnetic field h is considered. In particular, we discuss some properties of the implicit boundary condition on the discrete level and the computation of the integral operator exploited in this context. An iterative technique is confirmed to be efficient in solving the arising, partly dense, complex linear system of equations. Furthermore, some test results, including timings for linear solvers are presented.

The purpose of this study is to explore the potential contribution of the metaverse to improve training and development as a function of human resource development (HRD) perspective. The authors explore the benefits and challenges of the metaverse and introduce cases of companies using the metaverse in training.

A narrative literature review was conducted to collect information on the metaverse in training. The authors reviewed peer- and non-peer-reviewed articles, book chapters, white papers, corporate websites and blogs and business magazines.

A total of 75 articles were reviewed, including 14 cases, which were summarized to demonstrate how companies are applying metaverse technology in training contexts. For a more in-depth review, three cases were selected and summarized in terms of context, process and outcomes.

The metaverse is an emergent topic in HRD. It has the potential to revolutionize the functions of training and development through the combination of advanced technologies, including virtual reality, augmented reality and mixed reality. This article is the foundational attempt to provide a comprehensive summary of existing literature and case studies that highlight the potential of the metaverse in training within the context of HRD.

This study aims to carry out a systematic literature review to identify the factors stimulating the adoption of sustainable practices by wine tourism companies, from two perspectives: supply and demand.

To carry out the systematic literature review, a search in two databases – ISI Web of Science and SCOPUS – was performed to collect wine tourism and sustainability-related papers. This search allowed to identify 60 papers published during the period 2005–2020.

The analysis revealed three factors explaining the adoption of sustainable practices by wine tourism companies, from the supply perspective: competitiveness, innovation and territorial development. From the demand perspective, two factors that emerged are as follows: awareness and recognition. Sustainability strategies contribute to improving companies’ competitiveness; innovation is associated essentially with reducing the ecological footprint, whereas adaptation to new forms of consumption and territorial development is connected to economic and social development. Consumers are increasingly aware and choose sustainable and responsible lifestyles; this being reflected in their new preferences and the recognition given to firms that implement sustainable practices. The findings also show that companies are increasingly establishing goals and objectives taking sustainable development into consideration, and consumers are also aware of sustainability issues at the moment of acquiring products and services. In addition, the wine tourism sector was found to be growing worldwide.

The originality of the current study is based on focussing the supply and demand sides simultaneously. Furthermore, as no previous review was made in the subject of sustainability in the wine tourism sector, the findings are both innovative and original and provide valuable guidance for future research.

This research investigates the detailed mechanisms of how gamification affordances influence intrinsic and internalized extrinsic motivation and ultimately improve the quality and quantity of knowledge contribution.

Survey responses from 154 users of Stack Overflow in Portuguese were analyzed by the partial least squares–structural equation modeling approach to validate the research model.

Challenge and goal setting influence individuals to reach the flow state, which increases the quantity of knowledge contribution. Rewards enhance the quality of knowledge contribution through perceived self-worth. Social comparison increases perceived reputation, but its impact does not ultimately lead to knowledge contribution.

The current study differentiated types of motivation and dimensions of knowledge contribution when exploring the effects of gamification affordances. This perspective was proven helpful to understand the various gamification affordances' influence on knowledge contribution.

This paper aims to explore digital fashion products in the metaverse platform contexts and empirically examine the effect of the metaverse platform characteristics on the purchase intention of digital fashion products through users' flow experience and perceived value of the products.

A survey method was used in this study. Answers from 314 metaverse users were analyzed, and the hypotheses were tested using the structural equations modeling and bootstrapping analysis.

The analyses showed that telepresence, social interaction and economic flow had significant effects on users' flow experience among the metaverse platform characteristics, while the continuity and content creation of the metaverse platform did not have significant effects. The flow experience also appeared to have significant effects on multiple consumption values, including pleasure value, self-expression value and economic value. Last, the perceived pleasure value and economic value of digital fashion products had a positive effect on purchase intention.

The main contribution of this research is that it is one of the first empirical attempts to investigate individual consumers' perceptions and experiences of digital fashion products in the context of metaverse platforms.

To show for magnetostatic problems, how the numerically expensive post‐processing with the integral equation method (IEM) can be accelerated with the fast multipole method (FMM) and how this approach can be used to generate post‐processing data that allow for drawing streamlines.

In general, post‐processing with the IEM requires computation of the induced field due to solution variables, the field of permanent magnets and of free currents. For each of the three parts an approach to apply the FMM. With these approaches, large numbers of evaluation points can be used which are needed when streamlines are to be drawn. It is shown that this requires specially tailored meshes.

Post‐processing time can be largely reduced by applying the FMM. Additional memory requirements are acceptable even for high numbers of evaluation points. In order to obtain streamline breaks at material discontinuities, flat volume elements can be used.

The presented application of the FMM is applicable only to static problems.

Application of the FMM during post‐processing allows for a large number of evaluation points which are often required to visualize electromagnetic fields. This approach in combination with specially tailored meshes allows for drawing of streamlines.

The FMM is used not only to solve the field problem, but also for post‐processing which requires using the FMM to compute induced magnetic fields as well as the field due to permanent magnets and free currents. This leads to a speedup which allows for a large number of evaluation points which can be used, e.g. for high‐precision drawing of streamlines.

The purpose of this paper is to solve generic magnetostatic problems by BEM, by studying how to use a boundary integral equation (BIE) with the double layer charge as unknown derived from the scalar potential.

Since the double layer charge produces only the potential gap without disturbing the normal magnetic flux density, the field is accurately formulated even by one BIE with one unknown. Once the double layer charge is determined, Biot‐Savart's law gives easily the magnetic flux density.

The BIE using double layer charge is capable of treating robustly geometrical singularities at edges and corners. It is also capable of solving the problems with extremely high magnetic permeability.

The proposed BIE contains only the double layer charge while the conventional equations derived from the scalar potential contain the single and double layer charges as unknowns. In the multiply connected problems, the excitation potential in the material is derived from the magnetomotive force to represent the circulating fields due to multiply connected exciting currents.

This study aims to describe the effect of magnetic field (MF) on the corrosion rate of N-80 carbon steel [N-80 carbon steel (CS)] in concentrated (12.5 Wt.%, 3.8 M) hydrochloric acid (HCl) using gravimetric weight loss (WL) measurements and potentiodynamic polarization (PDP) in various conditions at ambient temperature.

The effects of MF intensity, magnetization time and elapsed time on corrosion rate (CR) reduction (η) were studied.

The experimental results show that pre-magnetization of HCl sharply decreases the corrosion rate of N-80 carbon steel (CS) in acid. The maximum η was found to be 94%. The surface of CS was analyzed with scanning electron microscope in normal and magnetized acid.

To the best of the authors’ knowledge, no studies have delved into the effects of magnetization on the corrosion rate of CS in concentrated HCl solutions. All of the previous research studies deal with an external MF that is applied on the reaction cell, but the magnetization of fluid before coming in contact with CS is investigated for the first time. In the present work, the influence of MF on the corrosion rate of CS in HCl is illustrated using gravimetric WL and PDP methods. The effects of MF intensity as well as period of magnetization and elapsed time were verified in more than 35 tests.