Value optimized log rotation for strength graded boards using computed tomography

Berglund, Anders; Johansson, Erik M. J.; Skog, Johan

doi:10.1007/s00107-014-0822-8

Cited by 7 publications

(8 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As a result, a shift of the shares of products towards the ones with a higher value is achieved. Therefore, the increase in value yield is not necessarily equal to the increase in volume yield which was already stated by Berglund et al (2014), Fredriksson (2014) and Rais et al (2017).…”

Section: Changing the Distribution Of Sawn Lumber By Ct-factorsmentioning

confidence: 89%

“…The possibility of automatically detecting knots in logs even with an industrial high speed CT was shown by Johansson et al (2013). Berglund et al (2014) used a CT to find the optimal sawing position and observed an increase in products value of up to 11%. Fredriksson (2014) showed the possibility to increase the value yield by 13% (with a volume yield increase of 0.5%) compared to the best position obtained by only using information about the outer shape of the logs.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Profitability gain expectations for computed tomography of sawn logs

2019

View full text Add to dashboard Cite

As the wood sawing industry in Central Europe is highly competitive, sawmills constantly try to increase their efficiency in the production process. The computed tomography (CT) technology is a promising way to increase the economic outcome of the sawing process. Nevertheless, the number of successful industry applications is still rare. In this study, the potential advantages of a roundwood scanning CT in a sawmill which uses bandsaw technology are analysed. A discrete event simulation model covering most of the sawmill's activities was developed and six output-altering CT-factors were implemented to identify the effects of the CT on sawing strategies. The CT-factors are applied to all assortments and affect the output of the sawing process. Since the CT scanner presumably affects the selection of logs for the sawing process, each CT-factor scenario was applied to different log selection strategies. By testing several scenarios, the prospective economic impact of a CT scanner could be revealed and an investment appraisal was conducted. Under different assumptions, an internal rate of return of 5% up to 42% was calculated.

show abstract

Section: Changing the Distribution Of Sawn Lumber By Ct-factorsmentioning

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Profitability gain expectations for computed tomography of sawn logs

2019

View full text Add to dashboard Cite

show abstract

“…Accordingly, a decision can be made on whether or not to trust the knot models that follow from the collection and analysis of CT scanning data, and the authors concluded that using this criterion to sort logs could potentially aid both sawmills and researchers in their application of CT-based log models. Berglund et al (2014) investigated the potential value increase of Norway spruce sawn timber by rotating logs to their optimum position prior to sawing, compared with sawing all logs in hornsdown position. This study followed earlier work by Berglund et al (2013) in which log breakdown had been simulated for about 800 Norway spruce and 600 Scots pine logs.…”

Section: Knots and Rameal Tracesmentioning

confidence: 99%

“…Simulations included prices corresponding to different quality grades influenced by knot position and size. Berglund et al (2014) found that there is a potential value increase when a rotation aimed to maximize the value of each log is applied instead of processing all logs in the horns-down position. The authors indicated, however, that the potential value increase depends on the rotational error of the sawing machine and the price differences between quality grades.…”

Section: Knots and Rameal Tracesmentioning

confidence: 99%

Applications of computed tomography (CT) scanning technology in forest research: a timely update and review

Beaulieu

Dutilleul

2019

Can. J. For. Res.

View full text Add to dashboard Cite

Organic materials of woody plants are complex and show internal, structural, and morphological variations due to genetic and environmental influences. Variability can be observed in stems, branches, leaves, and roots. Nondestructive and noninvasive technologies have been proposed to assess this variability. Computed tomography (CT) scanning, originally designed for medical diagnostics, permits the measurement of wood properties in situ (e.g., wood density, moisture content, internal defects, annual growth) and crown traits that characterize branching pattern geometry and canopy space occupancy for small-sized trees. Since Wei et al.’s (2011, Can. J. For. Res. 41(11): 2120–2140, doi: 10.1139/x11-111 ) review on the assessment of wood quality for optimized manufacturing processes using a CT scanner, several important developments have occurred, motivating the preparation of an update. We provide technical clarifications about the scales of observation and resolution; report on recent studies in which CT scanning was applied with research objectives beyond wood quality assessment for an optimized manufacturing of forest products; and stress the importance of analytical procedures for the graphical and quantitative analyses of CT scanning data (images and numbers) and the need for specialized algorithms and software. With this review, readers are expected to be well informed of the avenues offered by CT scanning technology in forest research in general.

show abstract

“…1997) could be increased by 6-13% compared to horns-down sawing when log rotational position was governed by the detected knots. In a following study, where simulated sawn products were strength graded according to the Nordic standard INSTA 142, Berglund et al (2014) reported potential increase in value recovery of 5-11%. In both cases, the amount of value increase found was depending on whether a rotational error of the sawing machine was simulated or not.…”

Section: Introductionmentioning

confidence: 98%

Optimization potential for perception-oriented appearance classification by simulated sawing of computed tomography-scanned logs of Norway spruce

Breinig

Broman

Brüchert

et al. 2014

Wood Material Science & Engineering

View full text Add to dashboard Cite

Wood, as a natural material, has favourable properties in both technical and aesthetic aspects. Due to its inherent variability, production of high-quality sawn timber demands adequate control of log conversion, which is feasible with computed tomography (CT) log scanning. Existing appearance grading rules for sawn timber might not fully reflect people's visual perception of wood surfaces, and therefore, an alternative, more perception-oriented appearance classification could be beneficial. An appearance classification of sawn timber based on partial least squares discriminant analysis (PLS-DA) of knot-pattern variables was developed and tested. Knot-pattern variables derived from images of board faces were used in training PLS-DA models against an initial classification of the board faces previously established by aid of cluster analysis. Virtual board faces obtained from simulated breakdown of 57 CT-scanned Norway spruce logs were graded according to the developed classification. Visual assessment of the grading results indicated that the classification was largely consistent with human perception of board appearance. An initial estimation of the potential to optimize log rotation, based on CT data, for the established appearance grades was derived from the simulations. Considerable potential to increase the yield of a desired appearance grade, compared to conventional log positioning, was observed.

show abstract

Value optimized log rotation for strength graded boards using computed tomography

Cited by 7 publications

References 5 publications

Profitability gain expectations for computed tomography of sawn logs

Profitability gain expectations for computed tomography of sawn logs

Applications of computed tomography (CT) scanning technology in forest research: a timely update and review

Optimization potential for perception-oriented appearance classification by simulated sawing of computed tomography-scanned logs of Norway spruce

Contact Info

Product

Resources

About