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Double-diffusive convection under an external magnetic field has several industrial applications, and how the magnetic field affects flow and heat and mass transfer is a research focus. This paper studies the dynamical behavior of two-dimensional double-diffusive convection in a uniform magnetic field is investigated using a high-accuracy numerical method. The effects of the magnetic field strength on the flow and on the heat and mass transfer are analyzed, and the process of flow transition in the presence of a magnetic field is studied. The results show that, as the strength of the magnetic field increases, the flow is gradually inhibited, and most of the heat transfer occurs through conduction. For a fixed magnetic field strength, the temperature-dominated flow changes from periodic to chaotic, and finally back to periodic, as the orientation of the magnetic field increases. Two types of periodic flow occur in the transition route, namely, a simple periodic flow with an integer multiple of the fundamental frequency and a complex periodic flow with multiple lower-frequency subharmonic waves. In the presence of a strong magnetic field, the effect of the magnetic field orientation on the flow is significant. At high Rayleigh numbers and a fixed magnetic field strength, the heat transfer efficiency of a vertical magnetic field surpasses that of a horizontal magnetic field by approximately 50% when temperature is dominant, achieving a mass transfer efficiency of about 100%. In cases when concentration is dominant, the heat transfer efficiency of a vertical magnetic field is 20% higher than that of a horizontal magnetic field, and the mass transfer efficiency is approximately 60% higher for the vertical magnetic field compared to the horizontal magnetic field. The flow transitions from chaotic or periodic to steady as the Prandtl number increases. The solution branch bifurcates at certain Prandtl numbers, and hysteresis appears when Prandtl number is equal to 0.023. For low Rayleigh numbers, the heat and mass transfer efficiencies increase monotonically with increasing Prandtl number under a weak magnetic field but remain constant for various Prandtl numbers under a strong magnetic field. [ABSTRACT FROM AUTHOR]

Objective: this study analyzes the characteristics of support and balance control during backward slip induced by sit - to - stand movement and the related factors. Methods: ten subjects are tested for their slips on sliding platforms to measure their joint torque, proprioception and reaction time. Results: 1) The successful balance recovery is characterized by a significantly raised ground reaction force (GRF), action time and COP displacement in X and Y direction. 2) The IEMG change of tibialis anterior (TA), erector spinae (ES) and deltoideus (DE) increased significantly during backward slip. 3) Ankles force and proprioception is highly related to the adjustment time during backward slip. Conclusion; When encountered with sudden backward slip during sit - to - stand, it is the trend of human body people to always take backward recovery step against backward slip. Larger support base and more time can be acquired to adjust balance by greater stride of recovery step. Meanwhile, powerful arm swing is also important to balance control. [ABSTRACT FROM AUTHOR]