Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2011
Authors
Igor A. Yakovlev Carl Gunnar Fossdal Tore Skrøppa Harald Kvaalen Jorunn Elisabeth Olsen Øystein JohnsenAbstract
No abstract has been registered
Authors
Nicolae Scarlat Jean-Francois Dallemand Odd Jarle Skjelhaugen Dan Asplund Lars NesheimAbstract
No abstract has been registered
Authors
Holger LangeAbstract
Spatial dependencies among environmental variables are often quantified by spatial autocorrelation functions. The latter basically assume linearity and isotropy, requirements usually not satisfied for measured data. Typical symptoms of violated assumptions are biased parameter estimations. Relaxing the assumptions of linear dependencies and isotropy, we present a conceptual generalization of spatial analysis where locally varying anisotropies in the geographical space are uncovered by investigating nonlinear dependencies among observations. The framework is illustrated by generalizing two examples: distance decay relations and spatial filtering. The proposed alternative is based on geodesic ecological and anisotropic spatial distances.
Authors
Frank MillerAbstract
No abstract has been registered
Academic – Analysis of three-dimensional grain angle variation in Norway spruce stems
Peder Gjerdrum
Authors
Peder GjerdrumAbstract
Grain angle was observed on 178 discs equally spaced along each of 24 mostly quite large spruce stems, and a general model estimated for grain angle variation along the radial distance from pith. Due to the three-dimensional approach and the large-size stems, new variability was identified, as compared to traditional two-dimensional approach applied on moderate-sized stem discs. The model standard error was 2.3º; half of this variation can be attributed to combined stem and disc effects, and half to purely random variation. Standard error for the model estimated for individual discs was 1.6 º. Observed against the stem centroid, pith angle varies randomly with average close to zero and standard deviation 2.2º. The results should be applicable for wood quality modelling and for commercial sawn timber production.
Authors
Mette Vaarst Christoph Winckler Stephen Roderick Gidi Smolders Silvia Ivemeyer Jan Brinkman Cecilie Marie Mejdell Lindsay k Whistance Pip Nicholas Michael Walkenhorst Christine Leeb Solveig March Britt IF Henriksen Elisabeth Stöger Elisabeth Gratzer Berit Hansen Johann HuberAbstract
No abstract has been registered
Authors
Matthias Zielke Arne Hermansen John Beck JensenAbstract
No abstract has been registered
Authors
May Sæthre I. Godonou Trond Hofsvang Ghislain Tchoromi Tepa-Yotto B. JamesAbstract
No abstract has been registered
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No abstract has been registered
Abstract
No abstract has been registered