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The purpose of this paper is to propose a mechanism avoiding the topology optimization methods, and particularly those using gradient‐based algorithms, to be trapped in local minimizers when applied to the design of electromagnetic devices made of iron and permanent magnet.

Topology optimization methods aim at finding the optimal distribution of some materials in cells subdividing a design space, regarding a specific objective function. This paper suggests to consider that each cell contains an oriented microstructure of iron whose direction and shape are optimized by the method.

Coupled with convexity and sensitivity mappings quite common in the field of topology optimization, the use of the microstructure allows the optimization algorithm to converge systematically toward the same design. This achievement is illustrated on a practical case, i.e. the optimization of the rotor of a permanent magnet synchronous motor regarding its mean torque and under mass constraint. Also, this paper shows that intermediate iron materials can either be penalized or interpreted, thanks to the realistic physical relations derived from the iron microstructures.

This paper proposes a mechanism based on an iron microstructure for avoiding the topology optimization methods and the trap of local minimizers when applied to the design of electromagnetic devices made of iron and permanent magnet.

The paper aims at optimizing magnetic thrusts in the framework of the design of high‐dynamics linear actuators. The goal is to find the optimal topology of the permanent magnets in order to maximize the velocity of the actuator.

The optimization is performed by a topology optimization method. The design space is divided in cells in which the method have to distribute permanent magnets and determine their magnetization directions.

Several aspects of the optimization are discussed in the paper, such as the effect of the introduction of a weight constraint on the thrust. Some issues are highlighted regarding the length of design space for the moving part and the presence of local minimizers in the optimization problem.

Having different magnetization directions in each cell makes the manufacturing harder. The results could thus be completed either by the design of a system able to create such permanent magnets or by the introduction of a constraint limiting the number of magnetization directions.

Finding the optimal topology of magnetic thrusts is motivated by the interest in avoiding the shocks related to mechanical thrusts.

This paper applies the topology optimization approach for the design of magnetic thrusts in order to increase the performances of high‐dynamics linear actuators.

The purpose of this paper is to address the question of how two seemingly opposite principles – managerial control and autonomy – simultaneously affect, positively and negatively, managers’ motivation to develop together innovative practices in a community of practice (the Custoprog community).

A single-case study was conducted in the Custoprog community, during which 22 semi-directive interviews with Custoprog members were conducted over a period of eight months. Members are all EuroAirport middle managers of EuroAirport (a Western Europe international airport).

The findings highlight how Custoprog members experience the conflicting situation of enjoying some autonomy (granted by top management), while being subjected to some degree of managerial control. Our results focus on how these two opposite principles (control and autonomy) simultaneously (positively as well as negatively) affect the motivation of Custoprog members to develop innovative practices together.

The study is limited by the scope of the sample. Further research conducted in multiple communities of practice (CoPs) may therefore be useful for comparability purposes, and to generalize our results.

We provide a set of practical recommendations to steer CoPs effectively, by achieving a delicate balance between control and autonomy.

Our investigation contributes to understanding the strategic benefits of using CoPs as an informal means of developing and diffusing customer-related innovative practices.