Mathematical programming in assessment of the postmortem interval under conditions of linearly varying external temperature

Nedugov V.G.; Nedugov G.V.

doi:https://doi.org/10.17116/sudmed20256804134

Nedugov V.G.

Samara National Research University (Samara University) named after S.P. Korolev

ORCID: 0009-0007-7542-7235

Nedugov G.V.

Samara State Medical University

ORCID: 0000-0002-7380-3766

Mathematical programming in assessment of the postmortem interval under conditions of linearly varying external temperature

Authors:

Nedugov V.G., Nedugov G.V.

More about the authors

Journal: Forensic Medical Expertise. 2025;68(4): 34‑39

DOI: 10.17116/sudmed20256804134

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To cite this article:

Nedugov VG, Nedugov GV. Mathematical programming in assessment of the postmortem interval under conditions of linearly varying external temperature. Forensic Medical Expertise. 2025;68(4):34‑39. (In Russ.)
https://doi.org/10.17116/sudmed20256804134

Подписка 2026 Судебно-медицинская экспертиза (Forensic Medical Expertise)

Использование инфографики авторами научных работ

OBJECTIVE

To develop and implement a method for determining the postmortem interval and the marginal errors of its estimates under conditions of linearly varying external temperature in the format of an online application.

MATERIAL AND METHODS

A computer-assissted numerical search for the absolute minimum point of the objective function obtained from a system of nonlinear equations reflecting the results of double rectal or cranioencephalic thermometry of a corpse under conditions of linearly varying external temperature was carried out. The search algorithm was generalized to possible marginal errors in measuring the initial indicators of temperature and time. The code of the online program was compiled in Python 3.

RESULTS

A method based on an iterative nonlinear optimization algorithm for determining the postmortem interval in linearly varying external temperature has been developed. It allows using double rectal or cranioencephalic thermometry to consider the uniqueness of the corpse’s cooling conditions using double rectal or cranioencephalic thermometry, as well as to find the degree of uncertainty of computational estimates of the method caused by the impact of measurement errors. The method is implemented in the format of the Warm Bodies Z 2 online application.

CONCLUSION

The developed method and the online application implementing it are recommended to establish the postmortem interval.

Keywords:

postmortem interval

nonlinear programming

objective function

thermometry of the corpse

measurement errors

Authors:

Nedugov V.G.

Samara National Research University (Samara University) named after S.P. Korolev

ORCID: 0009-0007-7542-7235

Nedugov G.V.

Samara State Medical University

ORCID: 0000-0002-7380-3766

Received:

28.10.2024

Accepted:

02.11.2024

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References:

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