21 October 2025

Determining a person’s time of death is of great importance for criminal investigations, but also presents a challenge. Jenny Arpe’s master’s thesis at Linköping University presents a new method for determining the time of death using AI. For this she has now been awarded the Examenspris civilingenjör till Christopher Polhems minne, a master of science in engineering thesis prize awarded in memory of Christopher Polhem. This is the third time in four years that the award goes to a thesis project at LiU.

Red blood cell.
Jenny Arpe combined advanced machine learning with metabolic data to analyse biological changes after death. 

“It feels fantastic and deeply honouring. I’m proud that the work I’ve devoted so much time to is being recognised. For me personally, I’m delighted and honoured that my work has received this recognition,” says Jenny Arpe.

In her master’s thesis at LiU, Jenny Arpe combined advanced machine learning with metabolic data to analyse biological changes after death. By training an AI model on data from nearly 5,000 samples, she was able to show that accurate predictions of the time elapsed from a person’s death to measurement are possible.

Biomedical Engineering meets forensics

Jenny Arpe studied to become a Master of Science in Engineering at LiU and did her degree project at the Department of Biomedical Engineering in collaboration with the National Board of Forensic Medicine.

Jenny Arpe.
Jenny Arpe is awarded the Master of Science in Engineering thesis prize in Christopher Polhem’s memory for a new method of determining the time of death for bodies that have been deceased for an extended period.
“It feels meaningful that this area of research area is being highlighted. I believe that the potential for using machine learning in forensic medicine is great, and I hope that the prize can help generate even more interest in it,” says Jenny Arpe in a press release from Engineers of Sweden.

Her work has now been taken further by the research group at LiU and the National Board of Forensic Medicine. The results from her thesis have formed the basis for a scientific publication and have also been used as supporting material in new research funding applications.

“This is a pioneering interdisciplinary project that combines medicine and artificial intelligence and has the potential to influence both future research and practical forensic work. The work has been thoroughly carried out, is well-structured and demonstrates a great ability to turn theory into practical societal application,” says Ulrika Lindstrand, President of the Engineers of Sweden, the Swedish union for graduate engineers who award the Examenspris civilingenjör till Christopher Polhems minne prize.

About the award

Christopher Polhem (1661–1751) was one of Sweden’s most prominent innovators of all time. The thesis was selected in competition with 4,540 other Master of Science theses in 2024, with the technical higher education institutions having their own nomination processes.

The thesis award will be presented at the same time as the Polhem Prize 2025 winner is made public on 19 November.

Read more about the prize (in Swedish)

Contact

Research environment

Latest news from LiU

Neil Lagali vid utrustning för att undersöka ögonen.

Eye problems after COVID-19 can now be explained

Mild COVID-19 can cause severe and long-lasting eye problems, according to a study from LiU. The study also explains why it has been difficult for sufferers to get help: the abnormal eye behaviour cannot be detected by standard methods.

A woman kneeling down in a garden picking plants.

When soil becomes data – how digitalisation affects knowledge of soil health

How do we know whether soil is healthy? A new study from Linköping University shows that as knowledge about soil is increasingly translated into digital data, important insights about its biological life and local context risk being overlooked.

A close up of a person holding a camera.

LiU researchers push the boundaries of organic solar cells

Researchers at LiU have now demonstrated how organic solar cells can become more efficient than previously thought possible. The key is to extend the time that electrons in the material remain excited, which leads to improved performance.