Heikki Korpunen
Research Scientist
Biography
I am a forest engineering researcher with a particular emphasis on wood technology. My work involves traditional forest technology issues, such as studies on forest work time and productivity, research on wood value chains and tree bucking optimization, and studies on forest bioenergy logistics. I have also focused on forest industry production and cost modeling, as well as wood property analyses.
Education: Doctor of science in forestry, major: wood technology at the University of Helsinki, Finland (2015). Master of science in forestry, major: forest engineering and wood technology at the University of Joensuu, Finland (2006).
Abstract
Time and motion studies in forest operations benefit from video-based analysis, but manual annotation is time consuming. This pilot study aims to reduce analysis time by developing a deep-learning framework that classifies dashcam video into four work elements: crane out, cutting and processing, driving, and processing. Using a 3D ResNet-50 (PyTorchVideo) trained on manually annotated clips, the model achieved validation F1 = 0.88 and precision = 0.90, showing that spatiotemporal CNNs can capture rele-vant motion and appearance cues in forest environments. Overfitting indicates that more diverse data and better class balance are needed, but the approach shows clear potential to scale automated work-element monitoring and efficiency analysis.
Abstract
Rapporten presenterer resultater fra prosjektet «Demonstrasjon av omstilling til selektive hogster (DEMO)». Hovedmålet har vært å øke kunnskapen blant skogeiere, forvaltning og kunnskapsleverandører om omstilling av ensaldret skog til flersjiktet skog egnet for bledning. Metoden som har blitt testet er inspirert av forsøk i Nord-Amerika med omstilling av douglasgranplantasjer til skog med naturlig dynamikk. Der har man brukt ‘variable-density thinning’ (VDT) for å skape varierende tetthet som skal sette i gang foryngelsesprosesser på forskjellige tidspunkter og romlig spredt i bestandet. Metoden er her utviklet videre for å tilpasses omstilling til bledning i norsk skog med maskinell tynning. Det gis en beskrivelse av metoden, inkludert krav til egnede bestand. Det er gjennomført 15 praktiske drifter, samt etablert 4 feltforsøk hvor VDT testes ut. Erfaringene fra disse driftene utgjør grunnlaget for våre resultater og konklusjoner. Hovedfokuset har vært å teste metoden i grandominert skog. Det har imidlertid også vært interesse blant skogforvaltere for å teste metoden i furubestand. En tilpasning for å legge til rette for framtidig bledning i furudominert skog er derfor også beskrevet. De praktiske driftene og forsøksfeltene muliggjør undersøkelser av den videre utviklingen i bestandene de neste årtiene. Stikkord er etablering av foryngelse, vekstreaksjoner, stabilitet mot vindfelling, trærnes reaksjoner i tørkeperioder, og reaksjoner på skogbildet blant rekreasjonsbrukere.
Authors
Katrin Zimmer Ulf Lemke Irena Fundova Henrik Heräjärvi Mateusz Liziniewicz Marlene Cramer Stefanie Wieland Lukas Emmerich Thomas Uibel Anti Rohumaa Heikki Korpunen Grace Jones Ekaterina Nikolskaya Tom Jansen Anneli Adler Tom Mortelmans Ian Short Vincent Defays Karol TomczakAbstract
Birch is the third most abundant tree species in northern Europe and the Baltic region, but remains underutilized in several countries despite wood properties that support a broad range of applications, including pulp, veneer, plywood, furniture, flooring, joinery, and potentially structural products. Constraints on higher-value utilization include insufficient logistics for sorting and transport, the lack of standardized grading methods, and limited data infrastructure for systematic quality assessment across supply chains. The Nordic Forest Research (SNS) network VALUE:BIRCH was established to examine these constraints through transnational collaboration among researchers, industry actors, and students across northern Europe. In 2025 and 2026, the network held workshops in Borås, Sweden, and North Rhine-Westphalia, Germany, with emphasis on strength properties, grading, and quality assessment of birch wood. The activities integrated technical presentations, laboratory and field visits, and student contributions, enabling comparison of birch value chains across countries with differing levels of industrial development. The network identified shared technical and organizational bottlenecks related to birch silviculture and management, grading, mobilization, and market formation, while also strengthening inter-institutional co-creation and collaboration. The results indicate that coordinated work on grading systems, quality data, logistics, and market development is essential to support more efficient and value-adapted utilization of birch.
