Ballistic analysis of high-performance armor steel by numerical simulation.

In order to establish a connection between the ballistic performance and mechanical properties of armor steel, a ballistic simulation model was developed and subsequently validated for accuracy and reliability. The mechanical properties of the target plate were described using the Johnson-Cook constitutive relation. An analysis was conducted to investigate the impact of the J-C parameters of the target plate on its ballistic performance, revealing a strong linear relationship between them.

[Analysis of the thoracolumbar fracture with ankylosing spondylitis].

Objective: To review the clinical features of the thoracolumbar fracture with ankylosing spondylitis (AS) in order to avoid delayed or missed diagnosis.

Methods: Five patients of thoracolumbar fracture with AS treated from April 2005 to June 2007 in our department were studied retrospectively, male 4 cases, female 1 case, the age from 26- to 72-years-old with an average of 44.8 years.