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The torque harmonics generated by asynchronous machine slotting are essentially linked to air‐gap permeance variations due to the rotor rotation. These variations lead to machine inductance coefficient fluctuations which are at the begining of torque harmonics. So the problem consists to determine the permeance variation law as well as for its mean value that for its “harmonics”. The aim of this study is to end at analytical expressions which allow to calculate the torque harmonic magnitudes whatever the considered machine. In consequence the numerical methods (e.g. finite element method) are not appropriated because their implementation considering the rotation will be too long and, in the other hand, they only permit, from calculus results, to estimate this permeance variation law. To resolve this problem by analytical way this law must be characterized by a simple expression. That leads the authors to translate the complex phenomena, linked to the field line repartition in the slotting, by simple laws applied to a fictitious slot model. After presenting the selected model to characterize the slots, the authors introduce the angle per unit permeance notion which permits to make clear the air gap permeance variation law in function of rotor rotation. The experimental verifications which relate to inductance coefficients and torque harmonics permit to validate these permeance variation law and in consequence the selected fictitious slot model. The evolution of these quantities in function of the magnetic field magnitude inside the machine permits the authors to propose a fictitious slot model evolution law which can take the saturation into account.

The purpose of this paper is to suggest a procedure which makes it possible to reduce the radial vibrations of doubly salient switched reluctance motors (SRMs).

An analytical method for the SRM radial vibration determination is first described. It is then extended to the active vibration reduction. An auxiliary winding equips the stator. The paper explains how the corresponding currents have to be adjusted to achieve a simple and robust control, with a special emphasis about the compatibility of the main and auxiliary supplies and about the reduction control principle. At last, an example of drastic noise reduction is presented.

The proposed method makes possible to define the theoretical vibration spectrum of SRM and thus it gives the major components to be reduced. The feasibility of automating the principle of active reduction is shown. The process of active reduction shows that a vibration component can be diminished by over 90 percent.

The active reduction is applied for reducing one component of the vibration spectrum. Future developments will focus on the simultaneous reduction of several components of vibration spectrum.

The method offers an automated process to reduce considerably the component of highest amplitude in the vibration spectrum.

ONE OF OUR readers has suggested that, to help a busy eye scan the pages of this section of NLW for instant recognition of topics of interest to it, these notelets should highlight in bold type certain keywords which give a clue to their content. Then harassed children's librarians, for example, can ignore the small type immediately surrounding the accentuated words ‘opulent bosom’ as being quite obviously beyond his/her realm of professional interest.

Exploring subjective experiences of people living with dementia through qualitative research has become increasingly common in recent decades. Nonetheless, researchers have shared a number of ethical challenges in involving people living with dementia in research. A concept that has been influential in discussions about ethics within the field of dementia care, in particular, is person-centredness. A person-centred approach reflects values of respect for personhood and the rights of a person and of building mutual trust and understanding. This chapter presents my experience of adopting person-centred ethical practices in a sensory ethnographic study involving older adults living with dementia. I highlight person-centred ethical considerations at the design stage of my study and occasions during the conduct of my research when research methods and processes were adapted to further meet the needs of the participants. A person-centred approach required that I continually assessed the need to make ethical decisions in every aspect of the research process throughout its duration. Building and drawing on positive researcher–participant relationships to inform those decisions and an adaptable research design allowing research practices to be adapted in situ were therefore essential.

The aim of this paper is to show what the leaders themselves regard as the working ingredients in their mutual work situation that help to facilitate personal development.

In the paper data were collected through semi‐structured interviews with 14 leaders at low and middle management levels in different lines of business within the private and public sector. The analysis of the learning processes draws on the theory of transformative learning.

The paper revealed that joint leadership, according to the leaders, could provide the leaders themselves with a basis of personal development and learning. This depends on common core values, a supportive relationship and common work processes as well as complementarity, joint sense making and critical reflection.

The implies that joint leadership provides possibilities of transformative learning through examination of different points of view, through explicitly talking about habits of mind, and through stepwise changes of existing frames of reference. The results indicate that joint leadership offers the possibility of a deepened learning process in daily work in a communicative relationship where profound values and ways of acting are openly shared and critically‐reflected upon. Joint leadership should however not be forced on to managers.

The paper provides insights into learning processes for leaders, based on the possibilities, which can be created through joint leadership.