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Spinelli Raffaele Magagnotti Natascia Visser Rien O’Neal Brandon 《European Journal of Forest Research》2021,140(4):901-911
European Journal of Forest Research - As a generalization, harvested timber is extracted from forests either as trees or stems by skidders or as logs by forwarders. Coupled with harvesters,... 相似文献
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Replacing Steel Cable with Synthetic Rope to Reduce Operator Workload During Log Winching Operations
The authors conducted three comparative tests, to determine if the replacement of steel cable with synthetic rope may allow
reducing the physiological workload of forest operators assigned to log winching tasks. The tests were conducted in Northern
Italy, on the Alpine mountain and involved 7 volunteer subjects. The physiological workload was determined by measuring the
operator’s heart rate upon completion of every task, using heart-rate monitors. Test one was conducted under simplified, controlled
conditions and detected a statistically significant reduction of relative heart rate when carrying synthetic rope, as compared
to steel cable. However, tests two and three were performed under real operational conditions, and were inconclusive. Real
operational conditions are characterized by the interaction of many factors, which may confound the results of the tests,
or offset the benefits potentially obtained with the introduction of synthetic rope. Nevertheless, the introduction of synthetic
rope offers the benefit of easier handling, which was very much appreciated by all test subjects. 相似文献
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Natascia Magagnotti Giovanna Ottaviani Aalmo Mark Brown 《Scandinavian Journal of Forest Research》2016,31(6):602-610
Winching is among the most common logging techniques in small-scale forestry, but it is inefficient and hard on the operators. The authors conducted a comparative test to determine the benefits of introducing an auxiliary winch that automatically returned the winch cable to the loading site. Such device would make it unnecessary for a crew member to walk down to the winch and pull the cable back to the loading site. The tests were conducted in central Italy, on the Tuscan hills. The study involved six volunteers, who were meant to cover a wide range of age and physical fitness characteristics and were considered representative of the regional logging workforce. Physiological workload was determined by measuring the operators' heart rate for a half-day individual work session. Performance was determined by stop-watching all winching cycles, with and without the auxiliary winch. The auxiliary winch improved the efficiency of downhill winching, allowing operation by two workers only, instead of three. Winching cost decreased between 20% and 35%, while physiological workload decreased between 7% and 30%, depending on the operator. 相似文献
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There is an urgent need for new, mechanized systems that may restitute some profitability to buffer strip harvesting and motivate regular maintenance. An opportunity for innovation is offered by the growing success of chip-fed boilers, since the production of chips is simpler than that of logs and has a higher potential for cost reduction. Within this context, a study was conducted in Italy with the goals of: (a) designing three alternative chip harvesting methods for buffer strips, (b) field-testing the performance of each alternative, and (c) developing a model for estimating the cost of these methods under varying operational and economic conditions. The three harvesting methods reflected different mechanization levels, with escalating investment requirements. Overall, the study demonstrated that frequent maintenance of young, single row buffer strips generates profits only when thoroughly mechanized. Using a dedicated feller-buncher, a front-end loader for extraction and an industrial truck-mounted chipper brought the delivered cost below the 14 €/m3 loose chips (approximately 4 €/GJ) presently paid by the district heating stations. However, the intermediate-mechanization system showed the highest potential for improvements. The␣study generated a spreadsheet-based model for predicting the effects of varying work conditions and cost hypotheses. 相似文献