the effects of high temperature homogenization and low temperature annealing treatments on the microstructure and magnetic properties of sintered magnets of an nd17fe76.5b5cu1.5 type alloy have been investigated. the microstructure of the as-cast alloy, consisted of three phases including a nd2fe14b1 (2:14:1- type) matrix phase cu-containing nd-rich phase and free α-iron. the as-sintered magnet...

Cogging torque is the major limitation of axial flux permanent magnet motors. The reduction of cogging torque during the design process is highly desirable to enhance the overall performance of axial flux permanent magnet motors. This paper presents a double-layer magnet design technique for cogging torque reduction of axial flux permanent magnet motor. Initially, 250 W, 150 rpm axial flux brus...

This paper presented an improved analytical method for calculating the open-circuit magnetic field in the surface-mounted permanent magnet machines accounting for slots and eccentric magnet pole. Magnetic field produced by radial and parallel permanent magnet is equivalent to that produced by surface current according to equivalent surface-current method of permanent magnet. The model is divide...

This paper analyzed the effect of temperature on the permanent magnet flux and output torque. The major parameter which will impact the torque control accuracy of a surface mounted permanent magnet motor is the variation of the permanent magnet temperature. In addition, the temperature variation of the permanent magnet will also influence the maximum torque per ampere of the motor. To analyze t...

in this paper, the optimal design of a three phase surface mounted permanent magnet synchronous motor has been done by particle swarm optimization and bees algorithm. this machine has been designed for high speed applications, and an epoxy and glass fiber bandage is used for permanent magnet protection against centrifugal forces. the optimization has been done by new design equations to improve...

The Gyro centrifugal pump, developed as a totally implantable artificial heart, was designed with a free impeller in which the rotational shaft (male bearing) of the impeller was completely separated from the female bearing. For this type of pump, it is very important to keep the proper magnet balance (impeller-magnet and actuator-magnet balance) to prevent thrombus formation or bearing wear. W...

The relationships between hospital Magnet® status, nursing unit staffing, and patient falls were examined in a cross-sectional study using 2004 National Database of Nursing Quality Indicators (NDNQI®) data from 5,388 units in 108 Magnet and 528 non-Magnet hospitals. In multivariate models, the fall rate was 5% lower in Magnet than non-Magnet hospitals. An additional registered nurse (RN) hour p...

Foreign body ingestion is a common paediatric problem. In the majority of cases spontaneous passage occurs. Magnet ingestion is rare and solitary magnet ingestion usually does not cause any complications. A number of gastrointestinal complications have been reported, such as fistula formation, perforation and volvulus following multiple magnet ingestion. We review magnet ingestion and describe ...