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In this article, an analytical method is presented for modeling the complex air gap field distribution and the magnetic force of a novel permanent magnet (PM) bias hybrid magnetic thrust bearing (HMTB). This bearing has a very compact structure and is proposed to replace the traditional magnetic thrust bearings (MTBs) for high-speed rotor systems. The proposed method introduces the notion of the complicated air gap field, calculated from the Schwarz–Christoffel transformation of the air gap geometry, to take into account the effect of slot fringing and leakage. As a result, accurate solutions of the flux distribution and the bearing force can be obtained, which shows good agreement with the results of the finite-element method (FEM). The prototype of the HMTB is designed, analyzed, and tested. The results of the analytical model are compared with experimental data.

Compulsator provides an excellent approach to achieve compact energy storage and pulsed power generation for several multi-MJ, multi-GW applications, including electromagnetic launchers, directed energy systems, and fusion reactors. There is a continuous research effort toward increasing the power capability and compactness of this machine since its invention. In general, specific machine designs aim to maximize the output current and power by minimizing the transient inductance of the armature winding. The field and the inductance of the armature winding are some of the most important parameters in the compulsator design. This article presents the development of a generic method to analyze the magnetic fields and inductances of the armature windings in compulsators based on fundamental principles. It derives analytical models for inductance calculation in various types of alternators as unified terms of simplified formulas. These are used for the design, analysis, and optimization of all air-core, iron-core, compensated, and uncompensated pulsed alternators (PAs). By comparing the distribution of armature reaction fields and the self-inductances in compulsators having different configurations, this article investigates the basic relationships between the topology of the alternator and the fields and inductances. This is not limited only to the study of PAs but it can also be used in both slotless and air-core conventional machines.

The quality and safety of agricultural products is very important for farmers' professional cooperatives. This study incorporates the government, farmers' professional cooperatives and farmers into the evolutionary game model to explore the game relationship and evolutionary path of decision-making among the three parties related to the quality and safety of agricultural products. Through the dynamic analysis of decision-making replication, the analysis of strategy evolution stability and the verification of numerical simulation experiments, it is shown that the decision-making behavior of the government, farmers' professional cooperatives and farmers under the conditions of agricultural product quality and safety is the result of the game between three stakeholders; the government, farmers' professional cooperatives and farmers The evolution process of the decision-making behavior to the ideal state is affected by many factors, and the value ranges of different factors have different effects on the convergence speed of the three stakeholders to the ideal state; when certain conditions are met, the government, farmers' professional cooperatives and farmers' three The decision-making behavior of each stakeholder can evolve into an ideal state, and effective government supervision can promote the cooperatives to manage the green production of farmers, and then effectively encourage farmers to take the initiative in green production. In order to provide useful suggestions for the government to make safety supervision decisions, to effectively manage cooperatives, and to stimulate active green production behaviors by farmers.