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This paper presents the modeling of a current transformer by various methods with the FLUX3D software. The technique used is based on the finite element method coupled with electric circuits. A magnetic scalar potential reduced versus T₀ formulation (T₀ϕ−ϕ) taking into account the electric circuits with an air‐gap is used for this purpose. The air‐gap is described either by a thin volume region or by a surface region.

This paper presents the results of a series of tests made in order to validate the magneto‐thermal module of the new FLUX3D v3.40. The tool was conceived to solve the coupled problems of electromagnetic and thermal phenomena. The solving method of the program considers a thermal‐transient problem during a certain period of time and it solves, at each time step, the thermal and electromagnetic equations (in quasi‐stationary magneto‐harmonic formulation), alternatively. We have modelled the inductive longitudinal welding of steel pipes. The results of 3D simulations are compared with measurements on a laboratory device.

The purpose of this paper is to propose a general approach for the frequency‐domain homogenization of electromagnetic periodic structures. The method allows calculating macroscopic equivalent properties including local effects. It is based on the equivalence of active and reactive electromagnetic powers on an elementary cell. This work is applied to the modelling of eddy current losses in windings, by the use of the finite element method in 2D and 3D.

The approach is based on an homogenization technique, allowing describing local properties (permeability and conductivity) and local effects (eddy currents) of periodical structures, through macroscopic homogenized behaviour laws.

It was found that the presence of local loops of eddy currents at the local scale implies that the average values of the electric and magnetic field are different from the macroscopic fields. This implies some precautions to implement the homogenization. Furthermore, the question of the coupling of the macroscopic laws has been clarified.

The proposed method is limited to the frequency domain. Some additional work is necessary to extend the researches in the time domain.

The proposed methodology is applied for determining losses in coils with the finite element method. The major interest of the method is that it allows taking into account local effects (losses in particular), with a reduced computational time.

The method proposed in this paper is general and clarifies the principle of homogenization in the case of periodical structure in presence of local eddy currents (local loops of current).

The aim of this paper is to accelerate the convergence of iterative methods on ill‐conditioned linear systems of equations.

First a brief numerical analysis is given of left preconditioners on ill‐conditioned linear systems of equations. From this result, it is deduced that a double preconditioning approach may be better. Then, a double preconditioner based on an iterative diagonal scaling method and an incomplete factorization method is proposed. The efficiency of this approach is illustrated on two finite element models produced by computational electromagnetism.

The double preconditioning approach is efficient for 2D and 3D finite element problems. The bi‐conjugate gradient algorithm always converges when it is double preconditioned. This is not the case when a simple incomplete factorization method is applied. Furthermore, when the two preconditioning techniques lead to the convergence of the iterative solving method, the double preconditioner significantly reduces the number of iterations in comparison with the simple preconditioner. On the proposed 2D problem, the speed‐up is between 6 and 32. On the proposed 3D problem, the speed‐up is between 13 and 20. Finally, the approach seems to reduce the growth of the condition number when higher‐order finite elements are used.

The paper proposes a particular double preconditioning approach which can be applied to any invertible linear system of equations. A numerical evaluation on a singular linear system is also provided but no proof or analysis of stability is given for this case.

The paper presents a new preconditioning technique based on the combination of two very simple and elementary methods: a diagonal scaling method and an incomplete factorization process. Acceleration obtained from this approach is quite impressive.

To model magneto‐harmonic devices including solid conductors with holes when the skin depth is very small.

The 3D finite element magnetic scalar potential formulation combined with the surface impedance condition approximation is used. It allows the modelling of thin skin depth effect at low cost.

The paper shows how to use surface impedance condition for solid conductors with holes, when using the magnetic scalar potential. Specific equations must be added to respect Ampere's theorem. The paper establishes these equations and the coupling with the finite element formulation. The final system of equations is symmetric.

The formulation allows to treat linear material in the magneto‐harmonic assumption.

The use of surface impedance condition with the 3D finite element magnetic scalar potential formulation is well known. The originality is to take into account holes (multiply connected conductors).

No other research analyzes the formation of overall satisfaction across channels, including the reciprocal interactions between store and website satisfaction and the factors that moderate them. Therefore, the aim of the present study is to examine how overall customer satisfaction is formed from the image and perceived congruence of the two main existing channels and the satisfaction induced by each.

The online study covers 909 customers of a French mortar-to-click retailer specializing in women's and children's clothing. The conceptual model incorporates reciprocal interdependence between store satisfaction and website satisfaction. This model is tested using the procedure specific to non-recursive structural equation model.

Overall satisfaction with the retailer is not only generated by satisfaction with the store and the website, but also directly and indirectly by the image of each channel. The contribution of the variables depends on the personal and situational characteristics of the customer. Not only is the relationship confirmed from store satisfaction to website satisfaction, but for the first time, in rarer cases the reverse is also observed. On the other hand, while the perceived congruence of channels can improve satisfaction with the channel for certain types of customers, in other cases the congruence can also worsen customers' overall satisfaction.

The detailed analysis of the formation of this satisfaction shows the pre-eminence of the customer over the retailer's initiatives. A retailer may facilitate or encourage virtuous interaction between retailer's channels by making the transfer of information and products more fluid (click and collect for example); but in the end, the customer is the one who decides whether or not to bring the channels closer together.

Contrary to what the literature assumes, in some cases, the retailer's attempt to integrate the channels may even reduce overall satisfaction if customers do not want this integration, just as a high level of satisfaction on the website can reduce in-store satisfaction.

This research studies what full channel integration means for customers, how channels should be combined so that this integration is perceived by customers and whether a retailer under study can act on the same channel attributes regardless of the type of customer.

The research design uses an online survey of a full sample of 1,015 multichannel buyers, extracted from the behavioral databases of a French specialized retailer. This full sample is segmented into four sub-samples. The data are treated with backward multiple linear regressions.

Based on research in marketing and psychology, this study conceptually demonstrates that integrated interactions perceived by consumers are the outcome of a judgment of congruence that seek to build relationships between them in order to combine them better. Testing three hypotheses, the empirical study shows that channel integration is a psychological process: cumulative (individuals incorporate the information provided by the different channels rather than comparing them), selective (customers never take into account all the attributes of the channels) and subjective (the channel image attributes taken into account differ in number and quality from one type of customer to another).

Contrary to what the literature assumes, without ever demonstrating it, full integration does not imply that the retailer in question homogenizes or even matches up all the attributes of its channels. The retailer is thus able to act on attributes that promote this integration, while being relatively free to cultivate the incongruence of other attributes more likely to smoothly guide customers to a particular channel – in other words, a path midway between cross-channel and omnichannel.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

This study aims to explain the health impact of work demands and organization, job content, leadership and values in the workplace. It also explores the extent to which health conditions influence the meaning in life in late career.

The sample consisted of 1,330 Portuguese-based individuals aged 55–75 years. The structural equation modeling (SEM) was used for the data analysis and to test the research questions.

The results showed that stress and burnout are influenced by work demands and organization, job content, leadership and values in the workplace. Employment status had no influence. Health status affects the meaning in life.

Although participants were asked to answer the questionnaire bearing in mind their last work experience, retirees could have had difficulty reporting on their last work; therefore, in future research, the use of a qualitative methodology could also be equated as to complement richer information regarding past experiences in the work context.

Considering the main goals of the United Nations 2030 Agenda for sustainable development, this study contributes, namely, to the third one – Ensure healthy lives and promote well-being for all at all ages. In fact, directing a look at the condition in which older people work and at their health contributes not only to more productive organizations, to less spending of public money on health, but also to a more inclusive society. Bearing in mind workers are progressively retiring later and that the exposure to certain work conditions during the late career is problematic for organizations and for society in general, this study has practical and social implication.

Considering demographic changes and the aging of the active population in Portugal and the scarce studies carried out in the country concerning this relevant theme, the authors believe that the conclusions may constitute an important input for workplace policies regarding older workers. In addition, little research has focused on the effect of health in meaning in life.