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Xiaoyu Alan Zheng (Fed)

Xiaoyu Alan Zheng is a Mechanical Engineer in Sensor Science Division of the National Institute of Standards and Technology (NIST). He has a B.S. and M.S. in Mechanical Engineering and focuses his research on objective measurements and analysis of 2D/3D firearm toolmarks. He served six years on the Subcommittee for Firearms & Toolmarks in the NIST OSACs where his contributions led to the development of three standards surrounding the implementation of 3D technologies in the forensic laboratory. He has led multiple successful National Institute of Justice grant funded projects for the development of the NIST Ballistics Toolmark Research Database (NBTRD) as well as research into population statistics for firearms. He is currently the chair of the Technical Advisor committee for the Association of Firearm and Toolmark Examiners (AFTE) and the co-chair of the Technical Working Group for 3D Toolmark Technologies (TWG3D2T). His primary focus is currently the development of the national Reference Population Database of Firearm and Toolmarks (RPDFT). This project seeks to provide forensic firearm examiners the ability to include objective similarity metrics and associated statistical statements of certainty with their court testimonies.


Automated interpretation of firearm mark comparison results

Martin Baiker-Sørensen, Ivo Alberink, Laura Granell, Leen van der Ham, Erwin J.A.T. Mattijssen, Erich Smith, Johannes A. Soons, Peter Vergeer, Xiaoyu Alan Zheng
In this article an automated approach for interpretation of firearm mark comparison results is presented. First, similarity scores are derived for marks

Firearm examination: Examiner judgments and computer-based comparisons

Erwin J. Mattijssen, Cilia Witteman, Charles Berger, Xiaoyu Alan Zheng, Johannes A. Soons, Reinoud Stoel
Forensic firearm examination provides the court of law with information about the source of fired cartridge cases. We assessed the validity of source decisions

NIST Ballistics Toolmark Research Database

Xiaoyu Alan Zheng, Johannes A. Soons, Robert M. Thompson, Sushama P. Singh, Cerasela Constantin
In 2009, a report by the National Academies called into question, amongst other issues, the objectivity of visual toolmark identification by firearms examiners

NIST Ballistics Toolmark Research Database

Xiaoyu Alan Zheng, Johannes A. Soons, Robert M. Thompson
The NIST Ballistics Toolmark Research Database (NBTRD) is an open-access research database of bullet and cartridge case toolmark data. The development of the
Created April 7, 2019, Updated December 8, 2022