枪械射击残留物分布密度的分形研究

Fractal study on density distribution of gun shot residues

为了推测发射枪械类别、弹种、枪械射击距离,利用X光摄影记录六种枪械发射子弹射击残留物的金属微粒密度与射击距离之间的关系,关系曲线表明二者是非线性的且具有分形特征;应用分形理论和线性回归原理,对射击残留物中的金属微粒分布密度进行计算和分析。结果表明,同种子弹由不同种枪发射时,其分形维数相应不同但相差较少;而不同种子弹由不同种枪发射时,其分形维数不同且相差较大。因此分形维数可以用来描述枪械发射子弹时射击残留物中的金属微粒密度分布情况。

The relation between metallic particle density of the gun shot residues and the shooting distance in the shot bullets from six kinds of guns was recorded by using X-ray. The relation curve shows that they are nonlinear and have fractal characteristics. The density distribution of the metallic particles in gun shot residues was calculated and analyzed by using fractal theory and linear regression theory. The results show that the fractal dimensions of the same bullets shot by different guns are different but differ less and that the fractal dimension of the different bullets shot by different guns are different in significant. Therefore, the fractal dimension may be used to describe the density distribution of the metallic particles in shot residues of a gun. This paper is to provide the technical support of estimating the gun-and-bullet types as well as the shooting distance.