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The purpose of this paper is to investigate the transient performance of an induction machine coupled with a magnetic gear for industrial applications with low speed and high torque requirements. This new solution increases mechanical reliability and does not require maintenance and lubrication. The main objective is to study the direct-on-line starting ability of the electrical machine and its stability regarding a sudden change for the load torque.

A nonlinear analytical model for the induction machine and the magnetic gear is first developed. The model is then linearized around an operating point to obtain the transfer function between the load angle and the electromagnetic torque from which an analytical expression for the mechanical resonant frequency is obtained.

It is shown that the direct on-line starting is possible, if the moment of inertia of the load is not greater than a maximum value. Moreover, it is demonstrated that this new system present inherent overload protection.

A new high-performance direct-on-line starting electrical machine is proposed to achieve high torque at low speed without mechanical gear to improve reliability and reduce maintenance.

This paper aims to propose a new 3D electromagnetic model to compute translational motion eddy current in the conducting plate of a novel linear permanent magnet (PM) induction heater. The movement of the plate in a DC magnetic field created by a PM inductor generates induced currents that are at the origin of a heating power by Joule effect. These topologies have strong magnetic end effects. The analytical model developed in this work takes into account the finite length extremity effects of the conducting plate and the reaction field because of induced currents.

The developed model is based on the combination of the sub-domain’s method and the image’s theory. First, the magnetic field expressions because of the PMs are obtained by solving the three-dimensional Maxwell equations by the method of separation of variables, using a magnetic scalar potential formulation and a magnetic field strength formulation. Then, the motional eddy currents are computed using the Ampere law, and the finite length extremity effects of the conducting plate are taken into account using the image’s method. To analyze the accuracy of the proposed model, the obtained results are compared to those obtained from 3D finite element model (FEM) and from experimental tests performed on a prototype.

The results show that the developed analytical model is very accurate, even for geometries where the edge effects are very strong. It allows directly taking into account the finite length extremity effects (the transverse edge effects) of the conducting plate and the reaction field because of induced currents without the need of any correction factor. The proposed model also presents an important reduction in computation time compared to 3D finite element simulation, allowing fast analysis of linear PM induction heater.

The proposed electromagnetic analytical model can be used as a quick and accurate design tool for translational motion PM induction heater devices.

A new 3D analytical electromagnetic model, to find the induced power in the conducting plate of a novel translational motion induction heater has been developed. The studied heating device has a finite length and a finite width, which create edge effects that are not easily considered in calculation. The novelty of the presented method is the accurate 3D analytical model, which allows finding the real power heating and real distribution of the induced currents in the conducting plate without the need to use correction factor. The proposed model also takes into account the reaction field because of induced currents. In addition, the developed model improves an important reduction in the computation time compared with 3D FEM simulation.

The purpose of this study is to develop a magnetic resonance imaging (MRI)-safe iron-free electrical actuator for MR-guided surgical interventions.

The paper deals with the design of an MRI compatible electrical actuator. Three-dimensional electromagnetic and thermal analytical models have been developed to design the actuator. These models have been validated through 3D finite element (FE) computations. The analytical models have been inserted in an optimization procedure that uses genetic algorithms to find the optimal parameters of the actuator.

The analytical models are very fast and precise compared to the FE models. The computation time is 0.1 s for the electromagnetic analytical model and 3 min for the FE one. The optimized actuator does not perturb imaging sequence even if supplied with a current 10 times higher than its rated one. Indeed, the actuator’s magnetic field generated in the imaging area does not exceed 1 ppm of the B₀ field generated by the MRI scanner. The actuator can perform up to 25 biopsy cycles without any risk to the actuator or the patient since he maximum temperature rise of the actuator is about 20°C. The actuator is compact and lightweight compared to its pneumatic counterpart.

The MRI compatible actuator uses the B₀ field generated by scanner as inductor. The design procedure uses magneto-thermal coupled models that can be adapted to the design of a variety actuation systems working in MRI environment.

The purpose of this paper is the design study and realisation of portable low-field open MRI system.

The design of the magnetic resonance imaging (MRI) system is based on an optimization study using a genetic algorithm. Non-linear two-dimensional and three-dimensional numerical electromagnetic models are developed and inserted in the optimization environment.

The results are found to be consistent with those issued from fully experimental tests. The static field produced by the device is 0.295 T with a homogeneity of 2.8% (28,000 ppm) over 100 mm diameter sphere volume. The z-axis gradient coils are capable of generating switching gradients with an amplitude of 8 mT/m and a frequency of 1.2 kHz.

Our system is an open portable MRI which can be used in an ambulance. The open topology permits an easy access into the lateral sides when a surgery using surgical instrument with video feedback is needed.

The importance of integrating sustainability into business activities rises continuously. In addition to an established focus on forward logistics, there is a growing awareness of reverse logistics. Reverse logistics ensures sustainable practices and increases competitiveness for companies, but it also comes with challenges. Therefore, the implementation of reverse logistics is associated with uncertainties. This paper aims to fill this gap by analyzing the development and comprehensive potential of reverse logistics as a sustainability tool.

To bridge the research gap, a real-time Delphi study was conducted. Through an extensive desk research, semi-structured interviews and an expert workshop, 14 projections for the German food sector of 2040 were created. A total of 49 experts in the field of logistics, reverse logistics and food logistics assessed the future projections concerning estimated probability, impact and desirability of occurrence.

The findings derived lead to three possible future scenarios as well as potential drivers and barriers that food companies, the government and society need to consider to enable a successful transition toward implementing reverse logistics in food supply chains.

The study examined the future role of reverse logistics as a sustainability tool in food supply chains. The results serve as a framework for decision-making on the sustainable orientation of business practices, leading to increased competitiveness and resilient business strategy. Several implications are derived for practitioners, policymakers and society to promote reverse logistics. Methodologically, this study extends existing Delphi methods by conducting a quantitative dissent and sentiment analysis, considering various surface-level and deep-level diversity characteristics.

The implementation of reverse logistics (RL) as a strategic decision has gained significant attention amongst organisations due to its benefits to sustainable development. The purpose of this paper is to provide a comprehensive review of the literature to evaluate the performance of the RL process based on the three dimensions of sustainability including environmental, economic and social aspects.

Content analysis was adopted to collect and analyse the information.

The findings of this research show that most of the studies have focused on the performance evaluation of RL by considering the factors associated with economic and environmental performance. The social aspect of RL has been overlooked and requires investigation due to its contribution to positive social outcomes. In addition, no research has been conducted to assess the impact of each of the disposition options on the triple-bottom-line sustainability performance in one study.

Although RL can make a significant contribution to improving the sustainability performance of firms, little research has been undertaken on exploring the relationship between RL and sustainability performance. This paper provides practitioners, academics and researchers a broad and complete view of the relationship between RL and sustainability performance with suggestion for future research.

This paper aims to examine how employee perceptions of organizational context relate to willingness to mentor. This research will help organizations to understand the relationship between organizational context and willingness to mentor to encourage mentoring.

This study used a survey approach. Employees who worked in the development, production and marketing of pharmaceuticals were administered a survey questionnaire. Data were analyzed through structural equation modeling.

The findings showed that the downsizing experience was negatively related to willingness to mentor, and the threat of being downsized was negatively related to perceived organizational support. In contrast, perceived organizational support was positively related to organization-based self-esteem, which, in turn, was positively related to willingness to mentor.

The relationship between perceived organizational support and organization-based self-esteem, with its subsequent positive effect on willingness to mentor, indicates the importance of organizations’ providing their employees with needed organizational support. Conversely, the negative relationship between the downsizing experience and willingness to mentor, and the threat of being downsized and perceived organizational support, indicates the need to separate mentoring programs from downsizing events even if it means delaying the initiation of a mentoring programs.

Research on the impact of organizational context on willingness to mentor is limited, and this study helps to address that gap.