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In engineering, DIC is a widely used measurement technique. Its major advantage is that it provides real-time results (displacements, accelerations, stresses, strains, deformations) of the surface under examination relatively quickly and without contact. However, its application in medicine, biomechanics, and the field of criminalistics is novel. The present research focuses mainly on the frontier areas of forensics and medicine. The research aims to define the test boundary conditions and preparatory activities to measure the surface of the animal and then human skin. Injuries caused by low-energy ballistic bullets, blunt-force trauma, and cuts and punctures caused by knives and/or blades will be investigated. The present research focuses on puncture injuries in animal skin. The main challenge is to create a speckle pattern on the surface that can track deformation well. The research is about developing and validating this. The GOM ARAMIS measurement system was applied for the measurements. This paper demonstrates that a suitable preparation, painting procedure, and measurement setup has been established to measure the above effects, i.e., to identify displacements and deformations of up to tenths of a millimeter with sufficient accuracy. The evaluation of the results will also show that this method could be used in forensic applications, the automotive industry, medical orthopedics, and the textile industry.

Lithium-ion battery technology in the modern automotive industry utilizes highly temperature-sensitive batteries. Here, air cooling strategies will be the most applicable for the chosen example based on strategies for temperature control. Simulations have been utilized to evaluate the different thermal management strategies. A battery model was developed using the solutions offered by Computational Fluid Dynamics (CFD) simulation technology. It utilizes the heat produced by the discharge of the battery cells. Due to the simulation's limited computational capacity, the energy transfer model was implemented with a simplified but sufficiently complex physical mesh. Ten actual measurements were conducted in the laboratory to investigate the heating of the cell during the charging and discharging of 18650-type batteries. The results were applied to validate the simulation model. The simulation outcomes and thermal camera readings were compared. The cell-level numerical model was then extended to examine the temperature variation at the system level. The primary design objective is to achieve the highest energy density possible, which necessitates that the cells be constructed as closely as possible; however, increasing the distance between the cells can provide superior cooling from a thermal management perspective. The effect of varying the distance between individual cells on the system's heating was analyzed. Greater distance resulted in a more efficient heat transfer. It was also discovered that, in some instances, a small distance between cells produces inferior results compared to when constructed adjacently. A critical distance range has been established based on these simulations, which facilitates the placement of the cells.

This paper summarized some common grading curves of ballast layers and found that the content of 16-32 mm ballast particles ("middle-size particles" in this paper) had a significant effect on the direct shear performance of the ballast layer. In this paper, the direct shear tests of the ballast layers with different contents of middle-size particles were reproduced using the discrete element method (DEM). Two different compactions of the ballast samples were used, and the reasons for the changes of shear strength of the ballast layers with different size distributions were analyzed from macroscopic and microscopic perspectives. The results showed that the strengthening effect of the ballast due insertion of middle-particles could only be observed for normally compacted ballast, whereas the same insertion with fully compacted ballast would decrease the shear strengths properties. The fully compacted ballast is subjected to the dilation. The reason of the strengthening effect for the normally compacted ballast were the contraction and dilation processes. Insertion of the middle-size particles up to 20-30% at most increase the dilation processes. Thus, the results show that the ballast layers with conventional narrow particle size distribution (narrow PSD) have higher shear strength than wide range particle size distribution (wide range PSD) if the ballast is good fully compacted. Additionally, it should be noted that the number of small particles will increase during the lifecycle of the ballast layer due to corner brakeage and the external contamination. Moreover, the drainage aspects of the wide range PSD should be considered. Therefore, the excessive insertion of middle-size particles is not justified.