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The purpose of this paper is to investigate the moving boundary conditions on the sliding armature and rail (A/R) interface. As the computational domains involve both moving and stationary conductors, Lagrangian description and backward difference schemes are adopted for spatial and temporal discretization, arising discontinuities in variables. The proposed formulation can compute the current distribution under high velocities (∼km/s) without numerical oscillations and avoids mesh re-generation, saving computational resources.

The governing equations in Lagrangian description, backward difference schemes and derivations of moving boundary conditions are shown in detail. The interface matrix is explicitly enforced on the whole domain matrix and pseudocodes are presented for implementation. Moreover, shifted interpolated quantity method is proposed to deal with unevenly sized mesh, which can calculate acceleration scenarios and save computation resources under high velocities. Comparative calculations with previous methods under low velocities are conducted to verify the correctness of computational and physical models.

The current distributions with constant velocities are consistent with previous two-dimensional and low-velocity studies, further verifying the correctness of the method. The three-dimensional high-velocity results show that the current tends to concentrate near the trailing edge of A/R interface and diffuses into the bulks over time, with higher velocity contributing to less significant current diffusion. The velocity skin effect precedes the magnetic diffusion, conductivity and other factors that influence the current distribution.

The proposed methods can compute the current distributions in railgun under velocity accelerated to over 2,000 m/s, and the results provide more comprehensive understandings of the current evolution process under velocity skin effect in railgun.

Drawing upon compensatory ethics theory, this study explored the underlying mechanisms through which gossipers engaged in helping behavior as a form of compensation after initiating negative workplace gossip.

Through a two-wave field study of 394 Chinese employees, this study tests theoretical hypotheses using path analysis and bootstrapping methods.

The findings suggested that negative workplace gossip positively influenced the gossipers’ helping behavior through moral self-image and guilt. Moreover, moral reflectiveness not only positively moderated the impacts of negative workplace gossip on moral self-image and guilt but also positively moderated the mediating effects of moral self-image and guilt in the relationship between negative workplace gossip and helping behavior.

These results enrich the theoretical research on negative workplace gossip, offer new perspectives for studying this phenomenon and provide a theoretical basis and decision-making reference for management practices.