broj: 11-12/2002
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IZVORNI ZNANSTVENI ČLANCI | ||
Krpan, A. P. B., Poršinsky, T. | UDK 630* 360 + 662 (001) | |
The Productivity of Timberjack 1070 Harvester in Scotch Pine thinning pdf HR EN | 551 | |
Summary: This paper shows the research results of productivity and costs of mechanized felling and processing of wood by harvester Timberjack 1070 in the culture of conifers. The productivity of harvester was determined by time and work study method. Times of felling and processing wood by harvester were broken down into work components. Time consumptions of specific work components were measured by snap-back chronometry method with the record of the whole working day. The data on the size of felled trees and processed assortments were printed from the harvester computer. The collected data were processed by mathematical and statistical methods by use of a PC. The basic unit of analysis was the cut and processed tree.The analysis of work time consumptions of specific work components of felling and processing of wood by harvester showed no dependence between time consumption and size of felled trees. Putting into correlation the consumption of total harvester work time per tree with processed volume of assortment of each tree, the values were calculated of efficiency and productivity of harvester for each tree. The data were investigated by use of regression analysis and equalized by exponential curve with very strong correlation. The well known effect of the law of piece volume can be easily seen through the dependence of productivity and unit costs of felling and processing of wood by harvester on breast height diameter of felled trees. In felling and processing trees of 10 cm BHD (0.03 m3/tree) the harvester productivity is 2.3 m3/h (EUR 30.24 per m3) and in felling trees of 30 cm BHD (0.63 m3/tree), the harvester productivity is 25.4 m3/h (EUR 2.74 per m3). This paper also shows the comparison between productivity and unit costs of felling and processing of wood performed by chain saw and harvester depending on breast height diameter of the tree. The data related to machine rate have been taken from FBVA (Austria) database - the calculation of forest machines performance. In felling and processing wood, the chain saw productivity is lower from 22 % (10 cm BHD) to 16 % (30 cm BHD) in relation to harvester productivity. Unit costs of felling and processing wood by chain saw are lower from 4.8 times (10 cm BHD) to 3.6 times (30 cm BHD) in relation to mechanized felling and processing performed by harvester. Key words: cost per m3; cut-to-length harvesting method; harvester; productivity | ||
Vučetić, M. | UDK 630* 111 + 431 (001) | |
Weather Conditions and Comparison of the Forest Fire Season 2001 With the Long-term Mean Values pdf HR EN | 563 | |
PRETHODNO PRIOPĆENJE | ||
Anić, I., Oršanić, M., Detelić, M. | UDK 630* 429 + 231 | |
The Revitalisation of Degraded Forest Ecosystem After the Dieback of Pedunculate Oak - a Case Study in the Kalje Forest pdf HR EN | 575 | |
PREGLEDNI ČLANCI | ||
Frković, A. | UDK 630* 156 | |
On Croatian Deer Antlers pdf HR EN | 589 | |
IZLAGANJA NA ZNANSTVENIM I STRUČNIM SKUPOVIMA | ||
Starčević, T., Dundović, J., Knepr, J. | UDK 630* 156 + 180 | |
Forest Ecosystems Under the Circumstances of Separated Managements of Forests and Hunting Areas pdf HR EN | 595 | |
Majnarić, D. | UDK 630* 156 | |
Bear Management as a Task of State Forestry pdf HR EN | 601 | |
Raguž, D., Grubešić, M., Starčević, T. | UDK 630* 156 + 945 | |
The Tradition of Educating Forestry Personnel for the Needs of Hunting Management in the Republic of Croatia pdf HR EN | 613 | |
Vratarić, P., Tarnaj, I. | UDK 630* 156 + 135 | |
Hunting Management in State Forests as Key Factor in the Transfer of Red Deer (Cervus elaphus) and Wild Boar (Sus scrofa) Breeding Stock pdf HR EN | 617 | |
STRUČNI ČLANCI | ||
Križaj, D., Vodolšak, M. | UDK 630* 156 + 931 | |
Legal Provisions Regulating Game Loss and Damage from Game, and Protection Measures pdf HR EN | 623 | |