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Development and Evaluation of a Contrastive Learning Framework with Applications to Micromorphometry of Aluminum Powder used in Explosives

NCJ Number
Date Published
June 2023
61 pages

This paper explores the use of micromorphometry of aluminum powder used in explosives.


The authors of this paper aimed to use micromorphometric features of aluminum (Al) powder particles from a variety of different source types and apply statistics. The study concludes that the contrastive learning framework has the flexibility to handle quantifying evidential value for a variety of complex evidence forms. Aluminum powder is often used as a fuel in improvised explosive devices (IEDs). Individuals attempting to make IEDs often obtain it from legitimate commercial products or make it themselves using readily available Al starting materials. The characterization and differentiation between sources of Al powder may provide investigative and intelligence value. Each module of the contrastive learning framework can be substituted for any other applicable method. The compare and contrast modules of the contrastive learning framework can switch order.

Date Published: June 1, 2023