Autor: Jabłoński, W. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Zastosowanie programowania liniowego do optymalizacji zrywki drewna w trzebieżach
Application of the linear programming to optimizing wood extraction in thinnings
Autorzy:: Jabłoński, K.
Stempski, W.
Powiązania:: https://bibliotekanauki.pl/articles/989674.pdf
Data publikacji:: 2016
Wydawca:: Polskie Towarzystwo Leśne
Tematy:: lesnictwo
pozyskiwanie drewna
trzebieze
zrywka drewna
skladnice drewna
lokalizacja
optymalizacja
programowanie liniowe
linear programming
simplex algorithm
wood extraction
Opis:: Improvement cuttings conducted simultaneously on a few closely located areas, often face problems about how to prepare places that would serve as temporary landings for the harvested wood. This results from insufficient wood storing space in the forest and limited accessibility of the road network to wood hauling trucks, and leads to solutions, suggesting where small landings at tree−stand edge must be established, often in places rather distant form the thinning plots. When the wood is harvested on several thinning plots and should be transported to several small landings, a problem appears, where (i.e. to which landing) should the wood from a particular thinning plot be sent. The paper presents a model to solve this problem using the simplex algorithm, which is used in linear programming, a method applied in operations research. The wood was sourced from 15 thinning plots and 11 wood landings were located. In the model, the objective function presented total transportation work, to be spent on the wood extraction. The objective function was minimized. The problem was set up on the Excel spreadsheet and then resolved with the solver application. The model enabled to direct the harvested wood from different thinning plots to different landings in an optimal way. The results enabled to design the optimal wood extraction routes and to determine the allowable changes in the amounts of wood harvested from each thinning plot, which would not change the optimal solution. The model enabled also to calculate the minimum amount of transportation work, which would be spent during the optimized transportation of wood form particular thinning plots to particular wood landings.
Źródło:: Sylwan; 2016, 160, 01; 3-10
0039-7660
Pojawia się w:: Sylwan
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Optymalizacja zrywki drewna według kryterium minimalizacji pracy transportowej
Optimization of wood extraction from a clear-cut area according to the minimum transportation labour criterion
Autorzy:: Jabłoński, K.
Stempski, W.
Powiązania:: https://bibliotekanauki.pl/articles/989792.pdf
Data publikacji:: 2015
Wydawca:: Polskie Towarzystwo Leśne
Tematy:: lesnictwo
pozyskiwanie drewna
zrywka drewna
optymalizacja
prace transportowe
minimalizacja
programowanie liniowe
wood extraction
linear programming
transportation labour
Opis:: The objective of the study was to optimize wood extraction from a clear−cut area to several upper landings located at roads suited for wood haulage in a situation where the room for storing the wood was limited. The optimization process was to divide the clear−cut area into zones, from which the wood assortments should be transported to the different landings, so that the total transportation labour would be minimized. The research was conducted in Oborniki Forest District (western Poland) on a clear−cut area where the harvest of 2027 m³ of wood in four assortments was planned. The optimization method used presented a linear programming problem, which was formulated and solved with the Solver tool, available with a common spreadsheet. The clear−cut area was divided into a number of elementary plots, for which the quantities of the wood to be extracted and distances to the specified landings were determined. Altogether 189 such plots were defined, mostly square in shape and with 20 m long side. Three upper landings for each wood assortment, located at roads accessible to long−distance vehicles were also determined (fig. 1). The minimization of the transport labour needed for the extraction of different wood assortments was set as the criterion for the objective function. The results of the calculations, after putting them on the forest clear−cut area map (fig. 2), provided information about parts of the clear−cut area to which the wood should be extracted to. As it was expected, in the majority of cases, the model directed the wood to the landings, which were the closest, but in case of one assortment, the wood was directed to the landing located a bit further away than to the closest one. The model enabled to minimize the transportation labour spent on wood extraction from the clear−cut area. The calculations did not require any specific applications, enabling users of commonly available spreadsheets, equipped with a Solver tool to perform such calculations.
Źródło:: Sylwan; 2015, 159, 07; 540-548
0039-7660
Pojawia się w:: Sylwan
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Ocena możliwości rekompensaty miąższości drzew usuniętych ze szlaków zrywkowych zwiększonym przyrostem drzew granicznych
Assessing the possibility for the compensation of the volume of trees removed from the strip-roads by the increased increment of the edge trees
Autorzy:: Stempski, W.
Jabłoński, K.
Jakubowski, J.
Powiązania:: https://bibliotekanauki.pl/articles/974053.pdf
Data publikacji:: 2020
Wydawca:: Polskie Towarzystwo Leśne
Tematy:: szlaki zrywkowe
straty
rekompensata strat
drzewa graniczne
przyrost drzew
leśnictwo
drzewa usunięte ze szlaku
miąższość drzew
opening−up of stands
loss
increment from increased light influx
Opis:: The purpose of the research was to assess the possibility to compensate for the volume and its 10−year increase lost on future crop and trainer trees removed from the strip−roads by the increased growth of trees at their edge. The assessment comprised the estimation of the compensation period length and its percentage value 10 years after cutting the strip−roads. The analysis also comprised 5−year−long wood volume growth periods. The research was conducted in Scots pine stand, located in the eastern part in the Notecka Forest, the area managed by the Oborniki Forest District (western Poland). The strip−roads 2.5 m and 3.5 m of width were cut every 30 m in the 31−years−old stand. The measurements covered trees growing directly at the strip−roads as well as 2−4 m and 8−10 m away from them. The volume increase was calculated on the basis of tree− ring widths, on the cross−sections cut from the mid−points of 2−meter−long sections. The simulation of the possibility to compensate for the volume loss on future crop and trainer trees removed from strip−roads was conducted by calculating the difference of the average annual volume increments in a 10−year−long period for single trees from the 0−1 and 8−10 m zones, and for the sum of differences in annual increments between these zones as well as between the 2−4 m and 8−10 m zones. The results showed that the trees growing directly at the strip−roads had the largest periodic volume increments, and in case of the wider strip−roads the largest volume increments were also found on trees growing in the 2−4 m zone away from the strip−road. Simulations of the volume loss compensation period length and of 10−year volume increment showed that the compensation was possible in the variants with the wider strip−roads. 10 years after cutting the strip−roads, the compensation for the volume loss and for the lost 10−year volume increment, resulting from the increased increment on trees form the 0−1 m and 2−4 m, was 30% and 14%, in tree stands with wider and narrower strip−roads respectively.
Źródło:: Sylwan; 2020, 164, 01; 16-24
0039-7660
Pojawia się w:: Sylwan
Dostawca treści:: Biblioteka Nauki