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When rotor and stator teeth are close, the connecting air gap flux tube's cross-sectional area exceeds the tooth overlap area. This flux fringing effect is disregarded in the air gap permeance calculation of single-slice magnetic equivalent circuits (MECs) of electric motors with skewed rotors. This paper aims to extend an air gap permeance calculation method incorporating flux fringing for unskewed rotors to skewed and radially eccentric rotors.

Assuming axial independence, the unskewed air gap permeance is rotated according to the skew and integrated along the axial dimension, resulting in a first method. The integral is approximated analytically, resulting in a second method. Results are compared to a commonly used reference method and validated using a non-linear finite element method (FEM) simulation.

The proposed methods provide better alignment with the FEM validation compared to the reference method for skewed rotors and common rotor eccentricity, i.e. below 50% of the air gap length. The analytical method is shown to be competitive with the reference method regarding computational time cost.

Two novel air gap permeance methods are proposed for single-slice MECs with skewed rotors. Their characteristics are discussed and validated.

The purpose of this paper is to evaluate the implementation of a broad-scale team resource management (TRM) program on safety culture in a Dutch eye hospital, detailing the program’s content and procedures. Aviation-based TRM training is recognized as a useful approach to increase patient safety, but little is known about how it affects safety culture.

Pre- and post-assessments of the hospitals’ safety culture was based on interviews with ophthalmologists, anesthesiologists, residents, nurses, and support staff. Interim observations were made at training sessions and in daily hospital practice.

The program consisted of safety audits of processes and (team) activities, interactive classroom training sessions by aviation experts, a flight simulator session, and video recording of team activities with subsequent feedback. Medical professionals considered aviation experts inspiring role models and respected their non-hierarchical external perspective and focus on medical-technical issues. The post-assessment showed that ophthalmologists and other hospital staff had become increasingly aware of safety issues. The multidisciplinary approach promoted social (team) orientation that replaced the former functionally-oriented culture. The number of reported near-incidents greatly increased; the number of wrong-side surgeries stabilized to a minimum after an initial substantial reduction.

The study was observational and the hospital’s variety of efforts to improve safety culture prevented us from establishing a causal relation between improvement and any one specific intervention.

Aviation-based TRM training can be a useful to stimulate safety culture in hospitals. Safety and quality improvements are not single treatment interventions but complex socio-technical interventions. A multidisciplinary system approach and focus on “team” instead of “profession” seems both necessary and difficult in hospital care.