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The antiexplosion performance of an explosion-proof wall made of engineered cementitious composite was studied, using small-scale explosion-proof walls made of different materials and sizes that were subjected to on-site blasting. The dynamic responses of these walls were evaluated under blast loading using overpressure test system, digital image correlation (DIC) full-field strain testing, and high-speed photography recording of the crushing process. Analysis of the results of the overpressure and strain tests revealed the effect of the wall height on the overpressure behind the wall. Increasing the height of the explosion-proof wall can improve the protection ratio of the wall by more than 2%. The variation of full-field strain of different materials at the same burst ratio was obtained. The engineered cementitious composite explosion-proof wall was obviously superior to that of ordinary concrete in strain control on the back-explosion surface. These theoretical results provide references for the design of explosion-proof walls.

In augmented reality, interactive shadow casting between virtual and real objects is crucial for the consistency of the appearance of integrated scenes. Since real shadow-casting objects may not be fully visible in live videos, simulating the shadows that they cast onto virtual objects based on 3D reconstruction will fail. To address this issue, we propose a framework for simulating shadow interactions in live outdoor videos based on shadow edges. The simulation framework consists of two components: real-time casting shadow detection from live videos with moving viewpoints and generation of shadow volumes. First, we propose a novel split-based shadow detection framework that accounts for moving viewpoints. Then, a visual-perception-guided adaptive sampling strategy is developed to generate high-quality shadow volumes. The experimental results demonstrate that our algorithm achieves visually consistent shadow interactions for live outdoor videos, which significantly enhances the photorealism of the generated scenes for augmented reality (AR) applications.

A new material model of magnesium alloys, combining both Hill&rsquo, 48 yield function and Cazacu&rsquo, 06 yield function, was developed and programmed into LS-DYNA using user subroutine, in which both slip dominant and twinning/untwinning dominant hardening phenomena were included. First, a cyclic load test was performed, and its finite element analysis was carried out to verify the new material model. Then, the deformation behaviors of the magnesium crash box subjected to the compressive impact loading were investigated using the developed material model. Compared with the experimental results, the new material model accurately predicted the deformation characteristics of magnesium alloy parts. Additionally, the effect of the thickness distribution, initial deflection and contact friction coefficient in simulation models on deformation behaviors were investigated using this validated material model.