@inproceedings{BerendtPegelBlaskoetal.2020, author = {Berendt, Ferr{\´e}ol and Pegel, Erik and Blasko, Lubomir and Cremer, Tobias}, title = {Bark Characteristics of Scots Pine Logs}, series = {Environmental Sciences Proceedings}, booktitle = {Environmental Sciences Proceedings}, publisher = {MDPI}, issn = {2673-4931}, doi = {10.3390/IECF2020-08020}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2040}, pages = {1}, year = {2020}, abstract = {The wood of Scots pine (Pinus sylvestris L.) shows...}, language = {en} } @article{BerendtPegelBlaskoetal.2021, author = {Berendt, Ferr{\´e}ol and Pegel, Erik and Blasko, Lubomir and Cremer, Tobias}, title = {Bark proportion of Scots pine industrial wood}, series = {European Journal of Wood and Wood Products}, volume = {79}, journal = {European Journal of Wood and Wood Products}, number = {3}, publisher = {Springer Nature}, issn = {0018-3768}, doi = {10.1007/s00107-021-01657-7}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1975}, pages = {749 -- 752}, year = {2021}, abstract = {Bark characteristics are not only used in the forest-wood supply chain, for example to calculate standing volumes, but also to transform wood volumes and masses. In this study, bark thickness, bark volume and bark mass were analyzed on the basis of 150 Scots pine discs, with a mean diameter of 13 cm. The mean double bark thickness was 3.02 mm, the mean bark volume proportion was 5.6\% and mean bark mass proportion was 3.3\%. Bark proportions were significantly affected by the log-specific variables 'diameter over bark', 'proportion of bark damage' and 'double bark thickness'.}, language = {en} } @article{BerendtdeMiguelDiezWalloretal.2021, author = {Berendt, Ferr{\´e}ol and de Miguel-Diez, Felipe and Wallor, Evelyn and Blasko, Lubomir and Cremer, Tobias}, title = {Comparison of different approaches to estimate bark volume of industrial wood at disc and log scale}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, publisher = {Springer Nature}, issn = {2045-2322}, doi = {10.1038/s41598-021-95188-z}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1987}, pages = {8}, year = {2021}, abstract = {Within the wood supply chain, the measurement of roundwood plays a key role due to its high economic impact. While wood industry mainly processes the solid wood, the bark mostly remains as an industrial by-product. In Central Europe, it is common that the wood is sold over bark but that the price is calculated on a timber volume under bark. However, logs are often measured as stacks and, thus, the volume includes not only the solid wood content but also the bark portion. Mostly, the deduction factors used to estimate the solid wood content are based on bark thickness. The aim of this study was to compare the estimation of bark volume from scaling formulae with the real bark volume, obtained by xylometric technique. Moreover, the measurements were performed using logs under practice conditions and using discs under laboratory conditions. The mean bark volume was 6.9 dm3 and 26.4 cm3 for the Norway spruce logs and the Scots pine discs respectively. Whereas the results showed good performances regarding the root mean square error, the coefficient of determination (R2) and the mean absolute error for the volume estimation of the total volume of discs and logs (over bark), the performances were much lower for the bark volume estimations only.}, language = {en} } @techreport{CremerBerendtdeMiguelDiezetal.2020, type = {Working Paper}, author = {Cremer, Tobias and Berendt, Ferr{\´e}ol and de Miguel Diez, Felipe and Wolfgramm, Felix and Blasko, Lubomir}, title = {Accuracy of Photo-Optical Measurement of Wood Piles}, series = {Environmental Sciences Proceedings}, journal = {Environmental Sciences Proceedings}, number = {3(1)}, publisher = {MDPI}, issn = {2673-4931}, doi = {10.3390/IECF2020-08192}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2012}, pages = {4}, year = {2020}, abstract = {The accurate estimation of timber volume is of the utmost importance. For industrial timber, the volume is often estimated as stacked cubic meters. In addition to manual measurements, volume estimation is possible with photo-optical systems. Over 100 piles of industrial timber of broadleaved tree species were analyzed. In the study, a standard manual measurement method for the estimation of wood pile volumes was compared with a smartphone based photo-optical application for the determination of woodpile volume. Mean gross volume of the piles was approximately 56 m3 and mean width of piles was 9.43 m. A strong correlation was found between the manual measurements and the photo-optical measurement. However, volume estimation of large volume piles seems to perform better in comparison to piles with small volumes. Further research is needed to determine the effects of variables such as log quality or quality of pile on volume estimation accuracy.}, language = {en} } @article{deMiguelDiezRederWalloretal.2022, author = {de Miguel-D{\´i}ez, Felipe and Reder, Stefan and Wallor, Evelyn and Bahr, Henrik and Blasko, Lubomir and Mund, Jan-Peter and Cremer, Tobias}, title = {Further application of using a personal laser scanner and simultaneous localization and mapping technology to estimate the log's volume and its comparison with traditional methods}, series = {International Journal of Applied Earth Observation and Geoinformation}, journal = {International Journal of Applied Earth Observation and Geoinformation}, number = {109}, publisher = {Elsevier}, issn = {1872-826X}, doi = {10.1016/j.jag.2022.102779}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4496}, pages = {7}, year = {2022}, abstract = {The aim of this study was the development of a methodical processing line for estimating the log's volume from scanning logs using a long-range high-speed personal laser scanner (PLS) GeoSLAM ZEB HORIZON and simultaneous localization and mapping (SLAM) technology in an open-source software framework of Cloud Compare. Additionally, the accuracy and precision of using PLS and the suggested method when measuring roundwood volume was examined compared to measurements made using a xylometer and estimations obtained from applying the formulae of Huber, Smalian and Newton. For this purpose, several parameters were measured in 50 logs of Norway spruce with an average length of 2.53 m and a mean diameter of 19.97 cm. Afterwards, the volume of these 50 logs was measured with a xylometer. The results of these measurements served as reference values. The same 50 logs were subsequently scanned with the PLS. The scans were converted into point clouds and were analyzed in Cloud Compare to estimate the volume of the scanned logs. Next, the root mean square error (RMSE) and the mean bias error (MBE) as well as their relative values were calculated for the volumes determined in Cloud Compare and estimated with the above mentioned formulae. The calculated RMSE (and relative RMSE) determined a deviation of the logs' volumes estimated in Cloud Compare from the xylometric volumes of 2.88 dm3 (3.54\%) whereas the deviations of the log's volumes calculated applying the formulae of Huber, Smalian and Newton from the xylometric volumes were respectively 9.63 dm3 (11.83\%), 10.33 dm3 (12.69\%) and 4.69 dm3 (5.76\%). The calculated MBE (and relative MBE) showed that the estimated volumes in Cloud Compare and those using the formulae were overestimated, with the lowest overestimation of 0.10 dm3 (0.12\%) in Cloud Compare and the highest, 5.50 dm3 (6.75\%), using the Smalian formula. Therefore, it can be stated that results of suggested methodical processing line came closest to the logs' volumes obtained with the xylometer, i.e., they were more accurate and precise compared to the conventionally formulae for log's volume estimation. The implementation of this method has the potential filling a gap towards a wall-to-wall complete digitization of the roundwood commercialization and ensure transparency and acceptance between the stakeholders involved in the wood supply chain.}, language = {en} } @article{CremerBlasko2017, author = {Cremer, Tobias and Blasko, Lubomir}, title = {Analyse der fotooptischen Vermessung von Kiefernstamm- und -industrieholz im Vergleich zum Sektionsraumaß}, series = {Allgemeine Forst- und Jagdzeitung}, volume = {188}, journal = {Allgemeine Forst- und Jagdzeitung}, number = {7/8}, publisher = {J. D. Sauerl{\"a}nder}, issn = {0002-5852}, doi = {10.23765/afjz0002008}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4551}, pages = {127 -- 139}, year = {2017}, language = {de} } @article{BerendtBajalanWenigetal.2023, author = {Berendt, Ferr{\´e}ol and Bajalan, Iman and Wenig, Charlett and Hinds, Charlotte and Blaško, Ľubom{\´i}r and Cremer, Tobias}, title = {Estimation of Scots pine bark biomass delivered to the wood industry in Northern Germany}, series = {Central European Forestry Journal}, volume = {69}, journal = {Central European Forestry Journal}, number = {2}, publisher = {Sciendo}, issn = {2454-0358}, doi = {10.2478/forj-2022-0019}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6126}, pages = {89 -- 97}, year = {2023}, abstract = {Scots pine (Pinus sylvestris L.) is the most widely distributed pine species in the world. In Germany, as in many other European countries, it is a very important species both culturally and economically. Few studies have focused on bark volumes being delivered to the wood industry together with the roundwood, being potentially a valuable resource for material or energetic utilization. Therefore, logs from six different forest sites were collected and bark variables including double bark thickness (DBT) in three different categories, diameter, and bark damage (as a degree of miss-DBT) in three different categories, diameter, and bark damage (as a degree of miss-ing bark) were measured and analyzed in order to model bark volume (Vbark) and bark mass (Mbark). The correlation analysis using Pearson's method showed that the highest correlation coefficients were observed from the correla-tion between DBT and Vbark, as well as between DBT and Mbark. Also, results demonstrated that with DBT greater than 20 mm, the percentage of Vbark exceeded 20\%. Finally, different linear regression models were recommended to predict Vbark and Mbark based on the other variables. The results of this study can be used in different wood industries in order to predict bark volume and bark mass of e.g. truckloads or roundwood stacks.}, language = {en} }