Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 2: Property predictions from colour changes
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Marcos M. González-Peña
Abstract
In the woodworking industry, image analysis is routinely used for quality control and for matching and classification during various processes. An extension of these automated systems for the prediction of physical properties of thermally modified wood (TMW) is enticing, because to date there is no generalised procedure for the quality assurance of TMW. In this work, the feasibility of predicting 13 physical parameters from the analysis of colour changes is demonstrated using small thermally modified specimens of three wood species. Simple linear regression models for anti-swelling efficiency, nominal density, heat-induced weight loss and 10 strength parameters in six forms of stress were all very or highly significant, with R2 statistics for the best predictor from 0.24 to 0.94. ΔE* was found to be a better predictor than ΔL* for most properties. Multiple linear regression with 11 colour variables increased the prediction ability of most models in terms of R2, although these improvements varied with the property and species concerned. The best models altogether were obtained by partial least squares regression, with relative prediction error values >0 in all cases. Our results demonstrate that physical properties of small specimens of TMW can be efficiently predicted with only one after treatment measurement of colour in the CIEL*a*b* colour space by means of image analysis of TMW surfaces. We anticipate that our approach would be a starting point for more refined modelling of physical properties of larger wood members and other properties of interest in TMW (e.g., decay resistance).
©2009 by Walter de Gruyter Berlin New York
Articles in the same Issue
- Original Papers
- 2D-NMR (HSQC) difference spectra between specifically 13C-enriched and unenriched protolignin of Ginkgo biloba obtained in the solution state of whole cell wall material
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 1: Colour evolution and colour changes
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 2: Property predictions from colour changes
- The relationship found between fibre length and viscosity of three different commercial kraft pulps
- High-yield kraft pulping of Eucalyptus grandis Hill ex Maiden biotreated by Ceriporiopsis subvermispora under two different culture conditions
- Analysis of microwave vs. thermally assisted grafting of poly(methyl-vinyl ether co-maleic acid)-polyethylene glycol to birch kraft pulp
- Selective enzyme impregnation of chips to reduce specific refining energy in alkaline peroxide mechanical pulping
- Radical chain reactions in pyrolytic cleavage of the ether linkages of lignin model dimers and a trimer
- Quantitative chemical indicators to assess the gradation of compression wood
- Comparison of mechanical properties of thermally modified wood at growth ring and cell wall level by means of instrumented indentation tests
- Revisiting the transition between juvenile and mature wood: a comparison of fibre length, microfibril angle and relative wood density in lodgepole pine
- Characterization of the wood quality of pernambuco (Caesalpinia echinata Lam) by measurements of density, extractives content, microfibril angle, stiffness, color, and NIR spectroscopy
- An improved drying model for highly-impermeable hardwoods
- Neutron attenuation coefficients for non-invasive quantification of wood properties
- Topochemical investigations of cell walls in developing xylem of beech (Fagus sylvatica L.)
- Effects of substrate on laboratory spalting of sugar maple
- Short Notes
- Apigenin derivatives from Paulownia tomentosa Steud. var. tomentosa stem barks
- Forming limits for the bulk forming of solid wood
- Meetings
- Meetings
Articles in the same Issue
- Original Papers
- 2D-NMR (HSQC) difference spectra between specifically 13C-enriched and unenriched protolignin of Ginkgo biloba obtained in the solution state of whole cell wall material
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 1: Colour evolution and colour changes
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 2: Property predictions from colour changes
- The relationship found between fibre length and viscosity of three different commercial kraft pulps
- High-yield kraft pulping of Eucalyptus grandis Hill ex Maiden biotreated by Ceriporiopsis subvermispora under two different culture conditions
- Analysis of microwave vs. thermally assisted grafting of poly(methyl-vinyl ether co-maleic acid)-polyethylene glycol to birch kraft pulp
- Selective enzyme impregnation of chips to reduce specific refining energy in alkaline peroxide mechanical pulping
- Radical chain reactions in pyrolytic cleavage of the ether linkages of lignin model dimers and a trimer
- Quantitative chemical indicators to assess the gradation of compression wood
- Comparison of mechanical properties of thermally modified wood at growth ring and cell wall level by means of instrumented indentation tests
- Revisiting the transition between juvenile and mature wood: a comparison of fibre length, microfibril angle and relative wood density in lodgepole pine
- Characterization of the wood quality of pernambuco (Caesalpinia echinata Lam) by measurements of density, extractives content, microfibril angle, stiffness, color, and NIR spectroscopy
- An improved drying model for highly-impermeable hardwoods
- Neutron attenuation coefficients for non-invasive quantification of wood properties
- Topochemical investigations of cell walls in developing xylem of beech (Fagus sylvatica L.)
- Effects of substrate on laboratory spalting of sugar maple
- Short Notes
- Apigenin derivatives from Paulownia tomentosa Steud. var. tomentosa stem barks
- Forming limits for the bulk forming of solid wood
- Meetings
- Meetings
