Journal of Wood Science

, Volume 64, Issue 3, pp 220–225 | Cite as

Classification of the hot air heat treatment degree of larch wood using a multivariate analysis of near-infrared spectroscopy

  • Sang-Yun Yang
  • Yeonjung Han
  • Yoon-Seong Chang
  • Jun-Ho Park
  • Yonggun Park
  • Hyunwoo Chung
  • Hwanmyeong Yeo
Original Article


In this study, hot air heat treatments of larch (Larix kaempferi) wood specimens were conducted at various temperatures (160–220 °C) and times (1–12 h) to classify the degree of hot air heat treatment using near-infrared (NIR) spectroscopy. NIR reflectance spectra were acquired from specimen cross-sections and were then preprocessed using the standard normal variate. Hierarchical clustering analysis (HCA) using the complete linkage and squared Euclidean distance was conducted to classify the three degrees of heat treatment. A principal component score plot of the NIR spectra was well grouped by the HCA grouping result, and the first component reflected the cluster analysis grouping well. A partial least squares discriminant analysis was performed to develop the discriminant regression model of the three heat treatment degrees. The R2 and root mean square error of validation were 0.959 and 0.191, respectively. NIR is considered to be a good candidate to routinely measure the degree of hot air treatment for larch wood.


Larch Wood heat treatment Discriminant analysis Multivariate analysis Near-infrared spectroscopy 



This work was financially supported by the Forest Science & Technology Projects (Project No. S121315L010100) provided by Korea Forest Service. This work was financially supported by the Forest Science & Technology Projects (Project No. 2016009B10-1719-AB01) provided by Korea Forest Service.


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Copyright information

© The Japan Wood Research Society 2018

Authors and Affiliations

  1. 1.Department of Forest SciencesSeoul National UniversitySeoulRepublic of Korea
  2. 2.Department of Forest ProductsNational Institute of Forest ScienceSeoulRepublic of Korea
  3. 3.Materials R&D CenterSamsung SDI Co., Ltd.SuwonRepublic of Korea
  4. 4.Research Institute of Agriculture and Life SciencesSeoul National UniversitySeoulRepublic of Korea

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