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Use of near infared spectroscopy to predict the mechanical properties of six softwoods

Informally Refereed
Authors: Stephen S. Jelley, Timothy G. Rials, Leslie H. Groom, Chi-Leung So
Year: 2004
Type: Scientific Journal
Station: Southern Research Station
Source: Holzforschung 58:252-260


The visible and near infrared (NIR)(500-2400 nm) spectra and mechanical properties of almost 1000 small clear-wood samples from six softwood species: Pinus taeda L. (loblolly pine), Pinus palustris, Mill. (longleaf pine), Pinus elliottii Engelm. (slash pine), Pinus echinata Mill. (shortleaf pine), Pinus ponderosa Dougl. ex Laws (ponderosa pine), and Pseudotsuga menziesii (Mirb.) Franco (Douglas fir) were measured. Projection to Latent Structures (PLS) modeling showed that the NIR spectra of these softwoods could be used to predict the mechanical properties of the clear-wood samples. The correlation coefficients for most of these models were greater than 0.80. All six softwood species were combined into one data set and a PLS model was constructed that effectively predicted the strength properties of any of the individual softwoods. Reducing the spectral range to between 650 and 1050 nm only causes a slight decrease in the quality of the models. Using this narrow spectral range enables the use of smaller, faster, lighter, less expensive spectrometers that could be used either in the field or for process control applications.


Mechanical properties, near infrared, NIR, softwoods


Jelley, Stephen S.; Rials, Timothy G.; Groom, Leslie H.; So, Chi-Leung. 2004. Use of near infared spectroscopy to predict the mechanical properties of six softwoods. Holzforschung 58:252-260