Giant magnetocaloric effect for (Mn, Fe, V)2(P, Si) alloys with low hysteresis

The Fe₂P type Mn–Fe–P–Si alloys exhibit a giant magneto-elastic first-order transition, but the large hysteresis limits their performance. Crystal structure evolution and magnetocaloric performance were investigated by varying the Mn and Fe contents at a constant V substitution of 0.02 in Fe₂P-type (Mn_1.17-xFe...

Progressive failure mechanisms of geosynthetic-reinforced column-supported embankments over soft soil: Numerical analyses considering the cracks-induced softening

Cement-based columns in combination with geosynthetic reinforcement is a well-established soft ground improvement technique to enhance embankment stability. This paper aims to present a finite-element (FE) study based on a case history of a geosynthetic-reinforced column-supported (GRCS) embankment over soft soil. In this study, the columns...

Passive Earth Pressure in Narrow Cohesive-Frictional Backfills

A narrow backfill zone is formed when retaining walls are built near existing stabilized structures (e.g., rock faces). In such circumstances, the classical passive earth pressure coefficient is no longer applicable, and a correction factor is required for the design. This paper aims to develop analytical solutions for estimating the passive...

Ultra-low Hysteresis in Giant Magnetocaloric Mn_1-xV_xFe_0.95(P,Si,B) Compounds

Large thermal hysteresis in the (Mn,Fe)2(P,Si) system hinders an efficient heat exchange and thus limits the magnetocaloric applications. Substitution of manganese by vanadium in the Mn1-x1Vx1Fe0.95P0.593Si0.33B0.077 and Mn1-x2Vx2Fe0.95P0.563Si0.36B0.077 compounds enable a significant reduction in the thermal hysteresis without losing the giant...

Tuning the magneto-elastic transition of (Mn,Fe,V)₂(P,Si) alloys to low magnetic field applications

The first-order magneto-elastic transition in the Mn–Fe–P–Si alloys can be tailored by vanadium substitution. Alloys with a suitable V substitution provide an excellent magnetocaloric effect with minor hysteresis in low magnetic fields up to 1.2 T. Mössbauer measurements show that the hyperfine field is reduced by V substitution. Neutron...

Combined effect of annealing temperature and vanadium substitution for mangetocaloric Mn_1.2-xV_xFe_0.75P_0.5Si_0.5 alloys

Approaching the border of the first order transition and second order transition is significant to optimize the giant magnetocaloric materials performance. The influence of vanadium substitution in the Mn_1.2-xV_xFe_0.75P_0.5Si_0.5 alloys is investigated for annealing temperatures of 1323,...

Off-board Visual Odometry and Control of an Ultralight Quadrotor MAV

In this paper, we propose an approach to autonomously control a quadrotor micro aerial vehicle (MAV). With take-off weight of 50 g and 8-min flight endurance, the MAV platform codenamed ‘KayLion’ developed by the National University of Singapore (NUS) is able to perform autonomous flight with pre-planned path tracking. The vision-based...