scholarly journals Three-dimensional spiral grain pattern in five large Norway spruce stems

Silva Fennica ◽  
2009 ◽  
Vol 43 (3) ◽  
Author(s):  
Peder Gjerdrum ◽  
Mauro Bernabei
Keyword(s):  
Norway Spruce ◽  
Three Dimensional ◽  
Spiral Grain

Predicting spiral grain by computed tomography of Norway spruce

2002 ◽  
Vol 48 (6) ◽  
pp. 479-483 ◽  
Author(s):  
Paul Sepúlveda ◽  
Johan Oja ◽  
Anders Grönlund
Keyword(s):  
Computed Tomography ◽  
Norway Spruce ◽  
Spiral Grain

scholarly journals Genetic parameters for spiral-grain angle in two 19-year-old clonal Norway spruce trials

2002 ◽  
Vol 59 (5-6) ◽  
pp. 551-556 ◽  
Author(s):  
Bj�rn Hannrup ◽  
Michael Grabner ◽  
Bo Karlsson ◽  
Ulrich M�ller ◽  
Sabine Rosner ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Genetic Parameters ◽  
Spiral Grain ◽  
Grain Angle ◽  
Spiral Grain Angle

scholarly journals Three-dimensional elastic behaviour of common yew and Norway spruce

2008 ◽  
Vol 42 (8) ◽  
pp. 633-647 ◽  
Author(s):  
Daniel Keunecke ◽  
Stefan Hering ◽  
Peter Niemz
Keyword(s):  
Norway Spruce ◽  
Three Dimensional ◽  
Elastic Behaviour

Micro-CT measurements of within-ring variability in longitudinal hydraulic pathways in Norway spruce

IAWA Journal ◽  
2020 ◽  
Vol 41 (1) ◽  
pp. 12-29 ◽  
Author(s):  
Robin Adey-Johnson ◽  
J. Paul Mclean ◽  
Jan Van den Bulcke ◽  
Joris Van Acker ◽  
Peter J. McDonald
Keyword(s):  
Norway Spruce ◽  
Linear Density ◽  
Annual Ring ◽  
Growth Ring ◽  
Three Dimensional ◽  
Lumen Diameter ◽  
Micro Ct ◽  
Bordered Pit ◽  
Tracheid Length ◽  
New Information

Abstract This study aimed to define the variability in the microstructure of Norway spruce within an annual ring by examining differences between earlywood and latewood. In particular, we were interested in obtaining new information on bordered pit occurrence and locations relative to tracheid ends, plus the lumina dimensions and longitudinal overlap of tracheids that collectively define the longitudinal hydraulic pathways. A stacked series of X-ray micro-CT scans of an annual ring of Norway spruce were made and stitched together longitudinally to form a three-dimensional volume. The imaging resolution was carefully chosen to capture both longitudinal and transverse anatomical details. Measurements of tracheid length, overlap, radial lumen diameter, and bordered pit location were made semi-automatically using image analysis. The distribution of radial lumen diameter was used to define earlywood and latewood. Then bordered pit linear density and spatial distribution, tracheid length and overlap were analysed, presented and contrasted for earlywood and latewood. Further differences between earlywood and latewood were found only in bordered pit linear density. Clear trends in radial lumen diameter and pit linear density were observed with radial position within the growth ring. These results provide new information on the variability of the Norway spruce microstructure within an annual ring.

The orbit of Pluto over a long interval of time

1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer
Keyword(s):  
Periodic Orbit ◽  
Numerical Integration ◽  
Restricted Problem ◽  
Three Dimensional ◽  
The Third ◽  
Circular Restricted Problem ◽  
Resonance Relation

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.

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