Head injuries incurred while playing ice hockey result from a range of impact energies. The objective of this study was to compare the impact energy attenuation range of conventional multi-impact materials incorporated in ice hockey helmets to a new multi-impact technology, referred to as a ‘chamber’. Three densities of 2.6 cm thick vinyl nitrile foam and two hardness values of the chamber were...

Victims of minor traumatic brain injury (mTBI), who show no clear morphological brain defects, frequently manifest cognitive, behavioral and emotional difficulties that can be long-lasting. In this paper we present a modified weight drop model used to deliver a closed head minimal traumatic brain injury to mice, which closely mimics real-life injuries and the symptoms observed in mTBI patients....

Board-level drop impact testing is a useful way to characterize the drop durability of the different soldered assemblies onto the printed circuit board (PCB). The characterization process is critical to the lead-free (Pb-free) solders that are replacing lead-based (Pb-based) solders. In this study, drop impact solder joint reliability for plastic ball grid array (PBGA), very-thin quad flat no-l...

Purpose: Despite the widespread use of cryotherapy in sports fields there is a lack of certain evidence of its impact of it on muscle activation especially following fatigue-induced exercise. This study aimed to assess the impact of cryotherapy alone and after plyometric exercises on knee muscle activation during the drop jump task. Method: 35 active female subjects (mean age of 22.74±2.10, m...

An effort is made to gain insight on the effect of carbon nanotubes (CNTs) on the impact response of carbon fiber reinforced composites (CFRs) under low velocity impact. Certain amount of CNTs could lead improvements in mechanical properties of composites. In the present investigation, ABAQUS/Explicit finite element code (FEM) is employed to investigate various damages modes of nano composites ...

Raindrop impact can be a major contributor to particle mobilization for soils and other granular materials. In previous work, water repellent soils, comprised of hydrophobic particles, have been shown to exhibit greater splash erosion losses under multiple drop impact. However, the underlying principal differences in splash behavior between hydrophobic and hydrophilic granular surfaces have not...