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Taking Measure

Just a Standard Blog

Xiaoyu Alan Zheng

Xiaoyu Alan Zheng is a mechanical engineer in the NIST Surface and Nanostructure Metrology Group. His research is focused on objective measurements and analysis of 2-D/3-D ballistics toolmarks. He is currently a member of the Subcommittee on Firearms & Toolmarks in the NIST OSAC as well as a technical adviser for AFTE.

Building a Firearms Toolmark Database

July 22, 2016

Although they are mass produced, every firearm is unique, and when fired, they leave unique markings called toolmarks on the bullet and cartridge casing. Law

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