Branch information extraction from Norway spruce using handheld laser scanning point clouds in Nordic forests by Olli Winberg, Jiri Pyörälä, Xiaowei Yu, Harri Kaartinen, Antero Kukko, Markus Holopainen, Johan Holmgren, Matti Lehtomäki, Juha Hyyppä

“…A total of 457 Norway spruce sample trees (Picea abies (L.) H. Karst.) from 13 spruce-dominated stands in southeastern Finland were used in the study. …”
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Multispectral Imagery Provides Benefits for Mapping Spruce Tree Decline Due to Bark Beetle Infestation When Acquired Late in the Season by Samuli Junttila, Roope Näsi, Niko Koivumäki, Mohammad Imangholiloo, Ninni Saarinen, Juha Raisio, Markus Holopainen, Hannu Hyyppä, Juha Hyyppä, Päivi Lyytikäinen-Saarenmaa, Mikko Vastaranta, Eija Honkavaara

“…The findings of this study indicate that multispectral UAV-based imagery is capable of classifying tree decline in Norway spruce trees during a bark beetle infestation.…”
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Feasibility of Bi-Temporal Airborne Laser Scanning Data in Detecting Species-Specific Individual Tree Crown Growth of Boreal Forests by Maryam Poorazimy, Ghasem Ronoud, Xiaowei Yu, Ville Luoma, Juha Hyyppä, Ninni Saarinen, Ville Kankare, Mikko Vastaranta

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Structural Changes in Boreal Forests Can Be Quantified Using Terrestrial Laser Scanning by Tuomas Yrttimaa, Ville Luoma, Ninni Saarinen, Ville Kankare, Samuli Junttila, Markus Holopainen, Juha Hyyppä, Mikko Vastaranta

“…The plot-level accuracy was higher in Scots pine-dominated sample plots than in Norway spruce-dominated and mixed-species sample plots. TLS-derived tree and forest structural attributes at time points T1 and T2 differed significantly from each other (<i>p</i> < 0.05). …”
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Unlocking Digitalization in Forest Operations with Viewshed Analysis to Improve GNSS Positioning Accuracy by Eugene Lopatin, Kari Väätäinen, Antero Kukko, Harri Kaartinen, Juha Hyyppä, Eero Holmström, Lauri Sikanen, Yrjö Nuutinen, Johanna Routa

“…This study evaluated the positioning accuracy of moving forest harvesters using global navigation satellite system (GNSS) signals under a forest canopy, and developed approaches for forecasting accuracy under a mature spruce canopy cover. Real-time kinematic positioning with a Trimble R12 receiver on top of a harvester achieved high positioning accuracy, with 86% of observations meeting a maximum precision of 8 mm. …”
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Feasibility of Hyperspectral Single Photon Lidar for Robust Autonomous Vehicle Perception by Josef Taher, Teemu Hakala, Anttoni Jaakkola, Heikki Hyyti, Antero Kukko, Petri Manninen, Jyri Maanpää, Juha Hyyppä

“…Multiple objects covering 10 different categories of road environment, such as car, dry asphalt, gravel road, snowy asphalt, wet asphalt, wall, granite, grass, moss, and spruce tree, were included in the experiments. We test the influence of the number of spectral channels and the number of frames on the classification accuracy with random forest classifier and find that the spectral information increases the classification accuracy in the high-photon flux regime from 50% to 94% with 2 channels and 30 channels, respectively. …”
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Using Leaf-Off and Leaf-On Multispectral Airborne Laser Scanning Data to Characterize Seedling Stands by Mohammad Imangholiloo, Ninni Saarinen, Markus Holopainen, Xiaowei Yu, Juha Hyyppä, Mikko Vastaranta

“…The highest overall accuracies in classification of Norway spruce, birch, and nontree class in leaf-off and leaf-on conditions obtained using SCI-Ch1 and SCI-Ch2 were 87.36% and 69.47%, respectively. …”
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Individual tree segmentation and species classification using high-density close-range multispectral laser scanning data by Aada Hakula, Lassi Ruoppa, Matti Lehtomäki, Xiaowei Yu, Antero Kukko, Harri Kaartinen, Josef Taher, Leena Matikainen, Eric Hyyppä, Ville Luoma, Markus Holopainen, Ville Kankare, Juha Hyyppä

“…The plots covered approximately 5500 trees in total, including Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H.Karst.), and deciduous trees such as Downy birch (Betula pubescens Ehrh.) and Silverbirch (Betula pendula Roth). …”
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