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An appropriate equivalent model is the key to the effective analysis of the system and structure in which permanent magnet takes part. At present, there are several equivalent models for calculating the interacting magnetic force between permanent magnets including magnetizing current, magnetic charge and magnetic dipole–dipole model. How to choose the most appropriate and efficient model still needs further discussion.

This paper chooses cuboid, cylindrical and spherical permanent magnets as calculating objects to investigate the detailed calculation procedures based on three equivalent models, magnetizing current, magnetic charge and magnetic dipole–dipole model. By comparing the accuracies of those models with experiment measurement, the applicability of three equivalent models for describing permanent magnets with different shapes is analyzed.

Similar calculation accuracies of the equivalent magnetizing current model and magnetic charge model are verified by comparison between simulation and experiment results. However, the magnetic dipole–dipole model can only accurately calculate for spherical magnet instead of other nonellipsoid magnets, because dipole model cannot describe the specific characteristics of magnet's shape, only sphere can be treated as the topological form of a dipole, namely a filled dot.

This work provides reference basis for choosing a proper model to calculate magnetic force in the design of electromechanical structures with permanent magnets. The applicability of different equivalent models describing permanent magnets with different shapes is discussed and the equivalence between the models is also analyzed.

The purpose of this paper is to investigate the effect of a magnetic field on the flow of a biomagnetic fluid.

The flow takes place in a straight circular duct and the magnetic field is produced by a line dipole placed perpendicularly to the longitudinal axis of the duct.

The numerical results show that the magnetic field affects the characteristics of the flow, the velocity components and the friction factor, even for medium field intensity. A relation is proposed for the maximum and minimum longitudinal pressure drop in the pipe.

From the present results it is obtained that it is important to take into account the magnetic properties of blood in the various applications that involve blood flow in the presence of a magnetic field.

This paper aims to investigate the effect of Powell–Eyring fluid induced by a stretched sheet. Heat and mass transfer under the influence of magnetic dipole over a stretching sheet are taken into account.

Nonlinear coupled governing equations are solved using the optimal homotopy asymptotic technique, and a computer software package BVPh 2.0 is used for numerical computations.

Impact of significant quantities is graphically examined. It is seen that the heat transfer deceases for higher values of viscous dissipation parameter, radiation parameter, Dufour number, whereas it increases for bigger values of Prandtl number. The numerical results have been validated through comparison with existing literature as a special case of proposed model and perceived that the Soret number has reining role to increase the rate of heat transfer.

To the best of the authors’ knowledge, this study is reported for the first time.

The differential magnetic gradient tensor system is usually constructed from the three-axis magnetic sensor array. While the effects of measurement error, sensor performance and baseline distance on localization performance of such systems have been widely reported, the research about the effect of spatial design of sensor array is less presented. This paper aims to provide a spatial design method of sensor array and corresponding optimization strategy to localization based on magnetic tensor gradient to get the optimum design of the sensor array. Based on the results of simulation, magnetic localization systems constructed from the proposed array and the traditional array have been built to carry out a localization experiment. The results of experiment have verified the effectiveness of magnetic localization based on the proposed array.

The authors focus on the localization of the magnetic target based on magnetic gradient by using three-axis magnetic sensor array and combine a design method with corresponding optimization strategy to get the optimum design of the sensor array.

This paper provides an array design and optimization method for magnetic target localization based on magnetic gradient to improve the localization performance.

In this paper, the authors focus on the magnetic localization based on magnetic gradient by using three-axis magnetic sensors and study the effect of the spatial design of sensor array on localization performance.

The HITSAT‐1 is the first small satellite developed by Harbin Institute of Technology (HIT) whose mission objective is to test several pivotal techniques. In the initial orbit period, the satellite is likely to tumble as the result of separating from the rocket. How to capture it promptly with finite magnetic torque is an important problem. In this paper, considering the restrictive conditions of the magnetic field, the variable structure control theory is used to cope with the magnetic torque. Because of using the reaction wheels and magnetorquers as the control actuators, the combination control algorithm has been adopted in the initial orbit period. The results of the computer simulation indicated that the algorithm has excellent robustness and can be designed and realized easily.

A bi‐scalar boundary‐integral approach to the static and monoharmonic electromagnetic field

The purpose of this paper is to establish the relevant quantitative methods for the investigation of the eddy and meridian fields of the general systemic yoyo model.

On the basis of established systemic yoyo models for electrons and positrons, flows of negative yoyo charges are naturally identified with electric currents so that use of the well‐developed quantitative methods can be made in electromagnetic theory to investigate the relationship between eddy and meridian fields of the general systemic yoyo model.

A general method is established on how to compute the intensity of the magnetic yoyo fields accompanying a moving yoyo charge or a canal of yoyo flow. A quantitative representation for magnetic yoyo fields is provided. And, the well‐known Ampere's law of electricity is generalized to the case of general yoyo flows.

By establishing an adequate quantitative method for the general systemic yoyo model, it should be possible to know more about the yoyo model and gain additional potential to successfully employ this model in various areas of learning, as proposed by Lin.

The purpose of this paper is to develop a theoretical design for the attitude control of electromagnetic formation flying (EMFF) satellites, present a nonlinear controller for the relative translational control of EMFF satellites and propose a novel method for the allocation of electromagnetic dipoles.

The feedback attitude control law, magnetic unloading algorithm and large angle manoeuvre algorithm are presented. Then, a terminal sliding mode controller for the relative translation control is put forward and the convergence is proved. Finally, the control allocation problem of electromagnetic dipoles is formulated as an optimization issue, and a hybrid particle swarm optimization (PSO) – sequential quadratic programming (SQP) algorithm to optimize the free dipoles. Three numerical simulations are carried out and results are compared.

The proposed attitude controller is effective for the sun-tracking process of EMFF satellites, and the magnetic unloading algorithm is valid. The formation-keeping scenario simulation demonstrates the effectiveness of the terminal sliding model controller and electromagnetic dipole calculation method.

The proposed method can be applied to solve the attitude and relative translation control problem of EMFF satellites in low earth orbits.

The paper analyses the attitude control problem of EMFF satellites systematically and proposes an innovative way for relative translational control and electromagnetic dipole allocation.

In this paper a continuum description of deformable magnetized material including long‐range magnetic forces and magnetostriction is presented. Herein, magnetostriction and long‐range forces on the one hand, and magnetization and deformation on the other hand are considered simultaneously. Therefore, neither a strict distinction between the deformation due to magnetic forces and due to magnetostriction, nor a separation of the total free energy into magnetic and elastic energy is involved.

We applied minimum norm estimations using different regularization techniques to the solution of the biomagnetic inverse field problem. Using magnetic field data measured with a multi‐channel‐SQUID‐sensor‐system we computed reconstruction of the impressed current density distributions which were generated by extended current sources placed inside a human torso phantom. The common inverse techniques usually applied in modern biomedical investigations in bioelectricity or biomagnetism are compared, and their aptitude for reconstruction of 3D current sources in space was evaluated. We analyzed the impact of using magnetic data, electrical data, and combination of both respectively on the localization of an equivalent current dipole (ECD). Finally, we use a visualization tool which enables a comparison of current density reconstruction. The study is, in parts, related to the new TEAM problem No. 31.