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Mechanical properties of semi-solid casting are dependent on multiple processing parameters, and improper processing parameters will not only reduce mean data but also increase variations. The present study investigated the impact of parameters in slurry preparation and heat treatment on the yield strength and ductility of T6 heat-treated A356 Al-Si alloy using rapid slurry forming (RSF) semi-solid casting. The focus was primarily on the robustness of mechanical properties based on Taguchi design method. By analyzing signal-to-noise ratio and minimum value calculated from x̄-3S, the optimum slurry preparation parameters and heat treatment parameters were determined to be no quench, enthalpy exchange material (EEM) temperature of 140 °C, EEM-to-melt ratio of 6mass%, stirring time of 18 s, solution heat treated at 520 °C for 2 h, and ageing heat treated at 190 °C for 6 h. In a small batch validation, the -3S yield strength and -3S elongation reach 256.1 MPa and 5.03% respectively, showing a satisfactory robustness. The hardness and microstructure of heat-treated samples with the best and worst properties were characterized to gain insight into the underlying mechanisms affecting the mean value and variations of mechanical properties. [ABSTRACT FROM AUTHOR]

Nowadays, to improve animal well being in livestock farming application, a wireless video sensor network (WVSN) can be deployed to early detect injury and monitor animals. They are composed of small embedded video and camera motes that capture video frames periodically and send them to a specific node called a sink. Sending all the captured images to the sink consumes a lot of energy on every sensor and may cause a bottleneck at the sink level. Energy consumption and bandwidth limitation are two important challenges in WVSNs because of the limited energy resources of the nodes and the medium scarcity. In this work, we introduce two mechanisms to reduce the overall number of frames sensed and sent to the sink. The first approach is applied on each sensor node, where the FRABID algorithm, a joint data reduction, and frame rate adaptation on sensing and transmission phases mechanism is introduced. This approach reduces the number of sensed frames based on a similarity method. The aim is to adapt the number of sensed frames based on the degree of difference between two consecutive sensed frames in each period. This adaptation technique maintains the accuracy of the video while capturing frames holding new information. This approach is validated through simulations using real data-sets from video sensors (Wang et al. in: 2014 IEEE conference on computer vision and pattern recognition workshops, pp 393–400, 2014). The results show that the amount of sensed data is reduced by more than 70% compared to a recent algorithm in Christian et al. (Multimed Tools Appl 79(3):1801–1819, 2020) while guaranteeing the detection of all the critical events at the sensor node level. The second approach exploits the Spatio-temporal correlation between neighboring nodes to reduce the number of captured frames. For that purpose, Synchronization with Frame Rate Adaptation SFRA algorithm is introduced where overlapping nodes capture frames in a synchronized fashion every N - 1 periods, where N is the number of overlapping sensor nodes. The results show more than 90% data reduction, surpassing other techniques in the literature at the level of the number of sensed frames by 20% at least. [ABSTRACT FROM AUTHOR]

Zinc Cr(III) passivation layer (Zn-PL) could effectively protect NdFeB materials from corrosion. However, long-term exposure of Zn-PL to ambient atmosphere would reduce its wettability spontaneously, which hinders or deteriorates the adhesion of post-deposited materials. To solve this issue, a multilayer developed by layer-by-layer assembly approach was designed, and alumina sol and silica sol were prepared. A polyacrylic acid (PAA) layer was firstly deposited on Zn-PL to remove the preabsorbed organic carbon and form poly(zinc acrylate). Then, Al2O3 and SiO2 sol–gel layers were sequentially assembled on PAA-coated Zn-PL. As a result, the hydrophobic Zn-PL turns into super-hydrophilic by coating organic–inorganic multilayers, which is attributed to the surface enrichment of hydrophilic hydroxyl groups and increases surface roughness. Furthermore, the super-hydrophilic surface displays excellent adhesion property without the negative effect on its other properties, which highlights a good prospect for a wide application of NdFeB or other potential materials. [ABSTRACT FROM AUTHOR]