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Magnetorheological Transmission Device (MRTD) is a controllable power regulation device using magnetorheological fluid as the transmission medium. It has characteristics of fast response, a wide range of speed regulations, and a pollution-free environment. The traditional pairwise transmission structure has serious heat generation problems during operation, resulting in low transmission efficiency. Therefore, we innovatively propose a multi-stage roller type MRTD to improve the heat generation problem fundamentally. The steady-state and transient temperature fields of the multi-stage roller type MRTD are simulated using the thermal analysis module in ANSYS based on the temperature field formulation. The variations of internal temperature at different slip powers are obtained. The results show that the designed multi-stage roller type MRTD has a good suppression of temperature rise. This study can provide a new approach to improve the thermal performance of MRTD. [ABSTRACT FROM AUTHOR]

Traditional belt deflection detection devices for underground belt conveyors in coal mines have problems, such as their single function, poor fault location and analysis accuracy, low automation level, and low reliability. In order to solve the defects of traditional detection devices, the belt deviation faults of the underground belt conveyor transport process require to be detected effectively and reliably. This paper proposes a belt deviation detection method based on machine vision. This method makes use of a global adaptive high dynamic range imaging method to complete the brightness enhancement processing of the underground image. Then the straight-line features of the conveyor belt edges are extracted using Canny edge detection and the Hough transform algorithm. In addition, a dual-baseline localization judgment method is proposed to realize the identification of band bias faults. Finally, a test bench for belt conveyor deviation was built. Testing experiments for different deviations were conducted. The accuracy of the tape deviation detection reached 99.45%. The method proposed in this study improves the reliability of belt deviation fault detection of underground belt conveyors in coal mines and has wide application prospects in the field of coal mining. [ABSTRACT FROM AUTHOR]

A magnetorheological fluid (MR fluid) is mainly composed of soft magnetic particles, surfactants, and the base carrier fluid. Among these, soft magnetic particles and the base carrier fluid influence the MR fluid significantly in a high-temperature environment. Therefore, a study was carried out to investigate the changes in the properties of soft magnetic particles and base carrier fluids in high-temperature environments. On this basis, a novel magnetorheological fluid with high-temperature resistance was prepared, and the novel magnetorheological fluid had excellent sedimentation stability, of which the sedimentation rate was only 4.42% after heat treatment at 150 °C followed by one-week placement. At 30 °C, the shear yield stress of the novel fluid was 9.47 kPa under the magnetic field of 817 mT: higher than the general magnetorheological fluid with the same mass fraction. Moreover, its shear yield stress was less affected by the high-temperature environment, reducing by only 4.03% from 10 °C to 70 °C. The novel MR fluid can be applied to a high-temperature environment, effectively expanding the application range of MR fluid. [ABSTRACT FROM AUTHOR]

Based on self‐consistency theory, this study examined the relationship between mentoring quality as perceived by protégés and protégés' proactive behavior. It focused on the mediating role of organization‐based self‐esteem (OBSE) and the moderating role of traditionality. To examine these relationships, we administrated three‐wave surveys to 237 subordinate–supervisor dyads in a construction enterprise. The results of hierarchical linear modeling demonstrated that (a) mentoring quality and proactive behavior had a positive relationship; (b) OBSE mediated this relationship; and (c) traditionality strengthened both the relationship between mentoring quality and OBSE and the indirect effect of mentoring quality on proactive behavior via OBSE. Our findings have theoretical and practical implications for research on mentoring and proactive behavior. [ABSTRACT FROM AUTHOR]

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Aiming to solve the problem of high-power magnetorheological fluid transmission heat dissipation, a new type of magnetorheological fluid drive disk is designed. The characteristics of the flow field and temperature field of high power MR fluid transmission devices are analyzed. Meanwhile, the influence of factors, such as rotating speed, inlet velocity, inlet position, diameter and number of magnetic columns, on the flow field are also investigated. Furthermore, the distribution characteristics of the ultimate slip power and the transient temperature field are obtained. The experimental platform of an MR fluid transmission device was established, and the torque transfer performance and heat dissipation performance were tested. The experimental results show that the device has good heat dissipation performance and can transfer high-power torque. [ABSTRACT FROM AUTHOR]

High-precision tension control is very important for industrial production. Benefit from the unique property of magnetorheological (MR) fluid, a MR clutch is a potential device in a tension control system due to its fast response and large output dynamics. In this paper, based on the detailed analysis of axial magnetic induction intensity generated by the coil along the radial distribution, a shear-mode MR clutch with uniform magnetic field distribution along the radial direction is proposed for the tension control system. A theoretical model of torque transmission and a magnetic circuit were derived, and a magnetostatic simulation was carried out to validate the effectiveness of the proposed circuit design. Experimental evaluation was conducted to investigate the static and dynamic transmission torque property. Finally, a proportional–integral–differential controller was designed to regulate the output torque. Experimental testing demonstrated the effectiveness and practical feasibility of the MR clutch in tension control. [ABSTRACT FROM AUTHOR]

Although previous studies provide diverse perspectives on the influences of abusive supervision, the moral perspective receives little attention in the literature. We rely on social cognitive theory to present a moral identity model of abusive supervision that accounts for the influences of perceiving abusive supervision on organizational and interpersonal deviance. In particular, we propose that employee moral identity mediates the positive relations between abusive supervision, as perceived by followers, and their subsequent organizational and interpersonal deviance. We also test the extent to which lone wolf tendencies alleviate the main negative impact of abusive supervision on moral identity and the indirect effect of abusive supervision on organizational and interpersonal deviance through moral identity. More specifically, when the level of lone wolf tendencies is high, the relationship between abusive supervision and moral identity, and the magnitude of the moral identity mediating mechanism will be weaker. Using multi-wave, multiple-source data collected in China, our findings support most of our hypotheses and offer insightful theoretical directions for mistreatment, morality, and disposition research. Our moderated mediation model serves as a springboard for future research to understand the social cognitive processes that link abusive supervision and deviant behavior from the moral perspective. [ABSTRACT FROM AUTHOR]