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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 OSACs 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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Taking Measure is the official blog of the National Institute of Standards and Technology (NIST).

It provides a behind-the-scenes look at NIST’s research and programs, covering a broad range of science and technology areas. Through this blog, NIST’s researchers and staff share why they do what they do and how today’s research will lead to tomorrow’s innovations.

The views presented here are those of the author and do not necessarily represent the views or policies of NIST.

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